National Library of Energy BETA

Sample records for level critical cavern

  1. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    E-Print Network [OSTI]

    Rutqvist, J.

    2013-01-01

    abandonment Underground gas storage: Worldwide ExperiencesCritical pressure for gas storage in unlined rock caverns.for the Brooklyn Union gas storage cavern at JFK Airport,

  2. Analysis of cavern stability at the West Hackberry SPR site.

    SciTech Connect (OSTI)

    Ehgartner, Brian L.; Sobolik, Steven Ronald

    2009-05-01

    This report presents computational analyses that simulate the structural response of caverns at the Strategic Petroleum Reserve (SPR) West Hackberry site. The cavern field comprises 22 caverns. Five caverns (6, 7, 8, 9, 11) were acquired from industry and have unusual shapes and a history dating back to 1946. The other 17 caverns (101-117) were leached according to SPR standards in the mid-1980s and have tall cylindrical shapes. The history of the caverns and their shapes are simulated in a three-dimensional geomechanics model of the site that predicts deformations, strains, and stresses. Future leaching scenarios corresponding to oil drawdowns using fresh water are also simulated by increasing the volume of the caverns. Cavern pressures are varied in the model to capture operational practices in the field. The results of the finite element model are interpreted to provide information on the current and future status of subsidence, well integrity, and cavern stability. The most significant results in this report are relevant to Cavern 6. The cavern is shaped like a bowl with a large ceiling span and is in close proximity to Cavern 9. The analyses predict tensile stresses at the edge of the ceiling during repressuization of Cavern 6 following workover conditions. During a workover the cavern is at low pressure to service a well. The wellhead pressures are atmospheric. When the workover is complete, the cavern is repressurized. The resulting elastic stresses are sufficient to cause tension around the edge of the large ceiling span. With time, these stresses relax to a compressive state because of salt creep. However, the potential for salt fracture and propagation exists, particularly towards Cavern 9. With only 200 ft of salt between the caverns, the operational consequences must be examined if the two caverns become connected. A critical time may be during a workover of Cavern 9 in part because of the operational vulnerabilities, but also because dilatant damage is predicted under the ledge that forms the lower lobe in the cavern. The remaining caverns have no significant issues regarding cavern stability and may be safely enlarged during subsequent oil drawdowns. Predicted well strains and subsidence are significant and consequently future remedial actions may be necessary. These predicted well strains certainly suggest appropriate monitoring through a well-logging program. Subsidence is currently being monitored.

  3. Gas intrusion into SPR caverns

    SciTech Connect (OSTI)

    Hinkebein, T.E.; Bauer, S.J.; Ehgartner, B.L.; Linn, J.K.; Neal, J.T.; Todd, J.L.; Kuhlman, P.S.; Gniady, C.T. [Sandia National Labs., Albuquerque, NM (United States). Underground Storage Technology Dept.; Giles, H.N. [Dept. of Energy, Washington, DC (United States). Strategic Petroleum Reserve

    1995-12-01

    The conditions and occurrence of gas in crude oil stored in Strategic Petroleum Reserve, SPR, caverns is characterized in this report. Many caverns in the SPR show that gas has intruded into the oil from the surrounding salt dome. Historical evidence and the analyses presented here suggest that gas will continue to intrude into many SPR caverns in the future. In considering why only some caverns contain gas, it is concluded that the naturally occurring spatial variability in salt permeability can explain the range of gas content measured in SPR caverns. Further, it is not possible to make a one-to-one correlation between specific geologic phenomena and the occurrence of gas in salt caverns. However, gas is concluded to be petrogenic in origin. Consequently, attempts have been made to associate the occurrence of gas with salt inhomogeneities including anomalies and other structural features. Two scenarios for actual gas intrusion into caverns were investigated for consistency with existing information. These scenarios are gas release during leaching and gas permeation through salt. Of these mechanisms, the greater consistency comes from the belief that gas permeates to caverns through the salt. A review of historical operating data for five Bryan Mound caverns loosely supports the hypothesis that higher operating pressures reduce gas intrusion into caverns. This conclusion supports a permeability intrusion mechanism. Further, it provides justification for operating the caverns near maximum operating pressure to minimize gas intrusion. Historical gas intrusion rates and estimates of future gas intrusion are given for all caverns.

  4. Threat of a sinkhole: A reevaluation of Cavern 4, Bayou Choctaw salt dome, Louisiana

    SciTech Connect (OSTI)

    Neal, J.T.; Todd, J.L.; Linn, J.K. [Sandia National Labs., Albuquerque, NM (United States); Magorian, T.R. [Magorian (Thomas R.), Amherst, NY (United States)

    1993-09-01

    Cavern Lake at Bayou Choctaw salt dome resulted from the failure of Cavern 7 in 1954. Uncontrolled solutioning of this cavern through the thin caprock had set the stage for overburden to collapse into the cavern below. A similar situation developed with nearby Cavern 4, but with less dissolutioning of the caprock. Because pressure loss was already a problem and because another 800 ft diameter lake would have endangered surface operations, solutioning of Cavern 4 was stopped and the cavern abandoned in 1957 in order to protect the already-small site. In 1978 the Strategic Petroleum Reserve (SPR) acquired a number of caverns at Bayou Choctaw, including Cavern 4, and the possible repeat of the Cavern 7 failure and formation of another lake thus became an issue. The cavern dimensions were re-sonared in 1980 for comparison with 1963 and 1977 surveys. Annual surface leveling between 1982--1992 showed less subsidence occurring than the site average, and a cavern monitoring system, installed in 1984, has revealed no anomalous motion. Repeat sonar surveys in 1992 showed very little, if any, change occurred since 1980 although a small amount of uncertainty exists as a result of changing sonar techniques. We conclude that significant additional solutioning or erosion of the caprock has not occurred and that there is no increased threat to SPR operations.

  5. Overfilling of cavern blamed for LPG blasts

    SciTech Connect (OSTI)

    Not Available

    1992-07-06

    Three explosions and a fire Apr. 7 at an LPG salt dome storage cavern near Brenham, Tex., were triggered when the cavern was overfilled, the Texas Railroad Commission (TRC) has reported. This paper reports that a TRC investigation found that LPG escaped to the surface at the Brenham site through brine injection tubing after excessive fill from an LPG line forced the cavern's water level below the brine tubing's bottom. At the surface, LPG was released into a brine storage pit where it turned into a dense, explosive vapor. At 7:08 a.m., the vapor was ignited by an unknown source. The resulting blast killed three persons and injured 19 and brought operations at the site to a halt.

  6. Manufactured caverns in carbonate rock

    DOE Patents [OSTI]

    Bruce, David A.; Falta, Ronald W.; Castle, James W.; Murdoch, Lawrence C.

    2007-01-02

    Disclosed is a process for manufacturing underground caverns suitable in one embodiment for storage of large volumes of gaseous or liquid materials. The method is an acid dissolution process that can be utilized to form caverns in carbonate rock formations. The caverns can be used to store large quantities of materials near transportation facilities or destination markets. The caverns can be used for storage of materials including fossil fuels, such as natural gas, refined products formed from fossil fuels, or waste materials, such as hazardous waste materials. The caverns can also be utilized for applications involving human access such as recreation or research. The method can also be utilized to form calcium chloride as a by-product of the cavern formation process.

  7. Analysis of cavern and well stability at the West Hackberry SPR site using a full-dome model.

    SciTech Connect (OSTI)

    Sobolik, Steven R.

    2015-08-01

    This report presents computational analyses that simulate the structural response of caverns at the Strategic Petroleum Reserve (SPR) West Hackberry site. The cavern field comprises 22 caverns. Five caverns (6, 7, 8, 9, 11) were acquired from industry and have unusual shapes and a history dating back to 1946. The other 17 caverns (101-117) were leached according to SPR standards in the mid-1980s and have tall cylindrical shapes. The history of the caverns and their shapes are simulated in a three-dimensional geomechanics model of the site that predicts deformations, strains, and stresses. Future leaching scenarios corresponding to oil drawdowns using fresh water are also simulated by increasing the volume of the caverns. Cavern pressures are varied in the model to capture operational practices in the field. The results of the finite element model are interpreted to provide information on the current and future status of subsidence, well integrity, and cavern stability. The most significant results in this report are relevant to Cavern 6. The cavern is shaped like a bowl with a large ceiling span and is in close proximity to Cavern 9. The analyses predict tensile stresses at the edge of the ceiling during repressurization of Cavern 6 following workover conditions. During a workover the cavern is at low pressure to service a well. The wellhead pressures are atmospheric. When the workover is complete, the cavern is repressurized. The resulting elastic stresses are sufficient to cause tension around the edge of the large ceiling span. With time, these stresses relax to a compressive state because of salt creep. However, the potential for salt fracture and propagation exists, particularly towards Cavern 9. With only 200 feet of salt between the caverns, the operational consequences must be examined if the two caverns become connected. A critical time may be during a workover of Cavern 9 in part because of the operational vulnerabilities, but also because dilatant damage is predicted under the ledge that forms the lower lobe in the cavern. The remaining caverns have no significant issues regarding cavern stability and may be safely enlarged during subsequent oil drawdowns. Predicted well strains and subsidence are significant and consequently future remedial actions may be necessary. These predicted well strains certainly suggest appropriate monitoring through a well-logging program. Subsidence is currently being monitored.

  8. Geomechanical Analysis and Design Considerations for Thin-Bedded Salt Caverns

    SciTech Connect (OSTI)

    Michael S. Bruno

    2005-06-15

    The bedded salt formations located throughout the United States are layered and interspersed with non-salt materials such as anhydrite, shale, dolomite and limestone. The salt layers often contain significant impurities. GRI and DOE have initialized this research proposal in order to increase the gas storage capabilities by providing operators with improved geotechnical design and operating guidelines for thin bedded salt caverns. Terralog has summarized the geologic conditions, pressure conditions, and critical design factors that may lead to: (1) Fracture in heterogeneous materials; (2) Differential deformation and bedding plane slip; (3) Propagation of damage around single and multiple cavern; and (4) Improved design recommendations for single and multiple cavern configurations in various bedded salt environments. The existing caverns within both the Permian Basin Complex and the Michigan and Appalachian Basins are normally found between 300 m to 1,000 m (1,000 ft to 3,300 ft) depth depending on local geology and salt dissolution depth. Currently, active cavern operations are found in the Midland and Anadarko Basins within the Permian Basin Complex and in the Appalachian and Michigan Basins. The Palo Duro and Delaware Basins within the Permian Basin Complex also offer salt cavern development potential. Terralog developed a number of numerical models for caverns located in thin bedded salt. A modified creep viscoplastic model has been developed and implemented in Flac3D to simulate the response of salt at the Permian, Michigan and Appalachian Basins. The formulation of the viscoplastic salt model, which is based on an empirical creep law developed for Waste Isolation Pilot Plant (WIPP) Program, is combined with the Drucker-Prager model to include the formation of damage and failure. The Permian salt lab test data provided by Pfeifle et al. 1983, are used to validate the assumptions made in the material model development. For the actual cavern simulations two baseline models are developed for single and multiple caverns, respectively. Different parameters that affect damage propagation and deformation of salt cavern, such as cavern pressure, operating conditions, cavern height/diameter ratio, overburden stiffness and roof thickness are analyzed and the respective results summarized. For multiple horizontal caverns numerical models are developed to determine the cavern interaction and the minimum safe center to center distance. A step by step methodology for operators to assess critical cavern design parameters for thin bedded salt formations is also presented.

  9. Synoptic Responses to Mountain Gravity Waves Encountering Directional Critical Levels

    E-Print Network [OSTI]

    Lott, Francois

    Synoptic Responses to Mountain Gravity Waves Encountering Directional Critical Levels ARMEL MARTIN the synoptic response to mountain gravity waves (GWs) absorbed at directional critical levels. The model in the midtroposphere. First, the authors consider the case of an idealized mountain range such that the orographic

  10. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    SciTech Connect (OSTI)

    Elcock, D.

    1998-03-05

    In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (referring to noncancer health effects) estimates that were well within the US Environmental Protection Agency (EPA) target range for acceptable exposure risk levels. These results led to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes.

  11. CAVERN ROOF STABILITY FOR NATURAL GAS STORAGE IN BEDDED SALT

    SciTech Connect (OSTI)

    DeVries, Kerry L; Mellegard, Kirby D; Callahan, Gary D; Goodman, William M

    2005-06-01

    This report documents research performed to develop a new stress-based criterion for predicting the onset of damage in salt formations surrounding natural gas storage caverns. Laboratory tests were conducted to investigate the effects of shear stress, mean stress, pore pressure, temperature, and Lode angle on the strength and creep characteristics of salt. The laboratory test data were used in the development of the new criterion. The laboratory results indicate that the strength of salt strongly depends on the mean stress and Lode angle. The strength of the salt does not appear to be sensitive to temperature. Pore pressure effects were not readily apparent until a significant level of damage was induced and the permeability was increased to allow penetration of the liquid permeant. Utilizing the new criterion, numerical simulations were used to estimate the minimum allowable gas pressure for hypothetical storage caverns located in a bedded salt formation. The simulations performed illustrate the influence that cavern roof span, depth, roof salt thickness, shale thickness, and shale stiffness have on the allowable operating pressure range. Interestingly, comparison of predictions using the new criterion with that of a commonly used criterion indicate that lower minimum gas pressures may be allowed for caverns at shallow depths. However, as cavern depth is increased, less conservative estimates for minimum gas pressure were determined by the new criterion.

  12. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    SciTech Connect (OSTI)

    Elcock, D.

    1998-03-10

    Salt caverns can be formed in underground salt formations incidentally as a result of mining or intentionally to create underground chambers for product storage or waste disposal. For more than 50 years, salt caverns have been used to store hydrocarbon products. Recently, concerns over the costs and environmental effects of land disposal and incineration have sparked interest in using salt caverns for waste disposal. Countries using or considering using salt caverns for waste disposal include Canada (oil-production wastes), Mexico (purged sulfates from salt evaporators), Germany (contaminated soils and ashes), the United Kingdom (organic residues), and the Netherlands (brine purification wastes). In the US, industry and the regulatory community are pursuing the use of salt caverns for disposal of oil-field wastes. In 1988, the US Environmental Protection Agency (EPA) issued a regulatory determination exempting wastes generated during oil and gas exploration and production (oil-field wastes) from federal hazardous waste regulations--even though such wastes may contain hazardous constituents. At the same time, EPA urged states to tighten their oil-field waste management regulations. The resulting restrictions have generated industry interest in the use of salt caverns for potentially economical and environmentally safe oil-field waste disposal. Before the practice can be implemented commercially, however, regulators need assurance that disposing of oil-field wastes in salt caverns is technically and legally feasible and that potential health effects associated with the practice are acceptable. In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. It investigated regulatory issues; the types of oil-field wastes suitable for cavern disposal; cavern design and location considerations; and disposal operations, closure and remediation issues. It determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could, from technical and legal perspectives, be suitable for disposing of oil-field wastes. On the basis of these findings, ANL subsequently conducted a preliminary risk assessment on the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in salt caverns. The methodology for the risk assessment included the following steps: identifying potential contaminants of concern; determining how humans could be exposed to these contaminants; assessing contaminant toxicities; estimating contaminant intakes; and estimating human cancer and noncancer risks. To estimate exposure routes and pathways, four postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (for noncancer health effects) estimates that were well within the EPA target range for acceptable exposure risk levels. These results lead to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes.

  13. New public information resources on salt caverns.

    SciTech Connect (OSTI)

    Tomasko, D.; Veil, J. A.

    1999-08-25

    For the past decade, interest has been growing in using underground salt caverns for disposing of wastes. The Railroad Commission of Texas has permitted a few caverns for disposal of nonhazardous oil field waste (NOW) and one cavern for disposal of naturally occurring radioactive materials (NORM) from oil field activities. Several salt caverns in Canada have also been permitted for disposal of NOW. In addition, oil and gas agencies in Louisiana and New Mexico are developing cavern disposal regulations. The US Department of Energy (DOE) has funded several studies to evaluate the technical feasibility, legality, economic viability, and risk of disposing of NOW and NORM in caverns. The results of these studies have been disseminated to the scientific and regulatory communities. However, as use of caverns for waste disposal increases, more government and industry representatives and members of the public will become aware of this practice and will need adequate information about how disposal caverns operate and the risks they pose. In anticipation of this need, DOE has fi.mded Argonne National Laboratory to develop a salt cavern public outreach program. Key components of this program are an informational brochure designed for nontechnical persons and a website that provides greater detail on cavern operations and allows downloadable access to the reports on the topic funded by DOE. This paper provides an overview of the public outreach program.

  14. New public information resources on salt caverns.

    SciTech Connect (OSTI)

    Tomasko, D.; Veil, J. A.

    1999-08-25

    For the past decade, interest has been growing in using underground salt caverns for disposing of wastes. The Railroad Commission of Texas has permitted a few caverns for disposal of nonhazardous oil field waste (NOW) and one cavern for disposal of naturally occurring radioactive materials (NORM) from oil field activities. Several salt caverns in Canada have also been permitted for disposal of NOW. In addition, oil and gas agencies in Louisiana and New Mexico are developing cavern disposal regulations. The US Department of Energy (DOE) has funded several studies to evaluate the technical feasibility, legality, economic viability, and risk of disposing of NOW and NORM in caverns. The results of these studies have been disseminated to the scientific and regulatory communities. However, as use of caverns for waste disposal increases, more government and industry representatives and members of the public will become aware of this practice and will need adequate information about how disposal caverns operate and the risks they pose. In anticipation of this need, DOE has funded Argonne National Laboratory to develop a salt cavern public outreach program. Key components of this program are an informational brochure designed for nontechnical persons and a website that provides greater detail on cavern operations and allows downloadable access to the reports on the topic funded by DOE. This paper provides an overview of the public outreach program.

  15. Modeling Space Shuttle Software Failures at Varying Criticality Levels

    E-Print Network [OSTI]

    Morgan, Joseph

    of a software failure data set for an industrial software development project. They propose models based criticality levels. A family of models based on transforms of cumulative time and cumulative failures the exponential, logarithmic, and power models. It also includes models based on transforms of the time per

  16. Numerical Simulations of Leakage from Underground LPG Storage Caverns

    E-Print Network [OSTI]

    Yamamoto, Hajime; Pruess, Karsten

    2004-01-01

    U. Case History: Blowout at an LPG Storage Cavern in Sweden,and Heads at an Underground LPG Storage Cavern Site, Journalof Leakage from Underground LPG Storage Caverns Hajime

  17. Risk analyses for disposing of nonhazardous oil field wastes in salt caverns

    SciTech Connect (OSTI)

    Tomasko, D.; Elcock, D.; Veil, J.

    1997-09-01

    Argonne National Laboratory (ANL) has completed an evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from nonhazardous oil field wastes (NOW) disposed of in domal salt caverns. In this assessment, several steps were used to evaluate potential human health risks: identifying potential contaminants of concern; determining how humans could be exposed to these contaminants; assessing the contaminants` toxicities; estimating contaminant intakes; and, finally, calculating human cancer and noncancer risks. Potential human health risks associated with hazardous substances (arsenic, benzene, cadmium, and chromium) in NOW were assessed under four postclosure cavern release scenarios: inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks or leaky interbeds, and a partial collapse of the cavern roof. To estimate potential human health risks for these scenarios, contaminant concentrations at the receptor were calculated using a one-dimensional solution to an advection/dispersion equation that included first order degradation. Even under worst-case conditions, the risks have been found to be within the US EPA target range for acceptable exposure levels. From a human health risk perspective, salt caverns can provide an acceptable disposal method for NOW.

  18. EIA - Natural Gas Pipeline Network - Salt Cavern Storage Reservoir...

    U.S. Energy Information Administration (EIA) Indexed Site

    Salt Cavern Storage Reservoir Configuration About U.S. Natural Gas Pipelines - Transporting Natural Gas based on data through 20072008 with selected updates Salt Cavern...

  19. Estimate of the risks of disposing nonhazardous oil field wastes into salt caverns

    SciTech Connect (OSTI)

    Tomasko, D.; Elcock, D.; Veil, J.

    1997-12-31

    Argonne National Laboratory (ANL) has completed an evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from nonhazardous oil field wastes (NOW) disposed in domal salt caverns. Potential human health risks associated with hazardous substances (arsenic, benzene, cadmium, and chromium) in NOW were assessed under four postclosure cavern release scenarios: inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks or leaky interbeds, and a partial collapse of the cavern roof. To estimate potential human health risks for these scenarios, contaminant concentrations at the receptor were calculated using a one-dimensional solution to an advection/dispersion equation that included first order degradation. Assuming a single, generic salt cavern and generic oil-field wastes, the best-estimate excess cancer risks ranged from 1.7 {times} 10{sup {minus}12} to 1.1 {times} 10{sup {minus}8} and hazard indices (referring to noncancer health effects) ranged from 7 {times} 10{sup {minus}9} to 7 {times} 10{sup {minus}4}. Under worse-case conditions in which the probability of cavern failure is 1.0, excess cancer risks ranged from 4.9 {times} 10{sup {minus}9} to 1.7 {times} 10{sup {minus}5} and hazard indices ranged from 7.0 {times} 10{sup {minus}4} to 0.07. Even under worst-case conditions, the risks are within the US Environmental Protection Agency (EPA) target range for acceptable exposure levels. From a human health risk perspective, salt caverns can, therefore, provide an acceptable disposal method for NOW.

  20. Effects of cavern depth on surface subsidence and storage loss of oil-filled caverns

    SciTech Connect (OSTI)

    Hoffman, E L

    1992-01-01

    Finite element analyses of oil-filled caverns were performed to investigate the effects of cavern depth on surface subsidence and storage loss, a primary performance criteria of SPR caverns. The finite element model used for this study was axisymmetric, approximating an infinite array of caverns spaced at 750 ft. The stratigraphy and cavern size were held constant while the cavern depth was varied between 1500 ft and 3000 ft in 500 ft increments. Thirty year simulations, the design life of the typical SPR cavern, were performed with boundary conditions modeling the oil pressure head applied to the cavern lining. A depth dependent temperature gradient of 0.012{degrees}F/ft was also applied to the model. The calculations were performed using ABAQUS, a general purpose of finite element analysis code. The user-defined subroutine option in ABAQUS was used to enter an elastic secondary creep model which includes temperature dependence. The calculations demonstrated that surface subsidence and storage loss rates increase with increasing depth. At lower depths the difference between the lithostatic stress and the oil pressure is greater. Thus, the effective stresses are greater, resulting in higher creep rates. Furthermore, at greater depths the cavern temperatures are higher which also produce higher creep rates. Together, these factors result in faster closure of the cavern. At the end of the 30 year simulations, a 1500 ft-deep cavern exhibited 4 percent storage loss and 4 ft of subsidence while a 3000 ft-deep cavern exhibited 33 percent storage loss and 44 ft of subsidence. The calculations also demonstrated that surface subsidence is directly related to the amount of storage loss. Deeper caverns exhibit more subsidence because the caverns exhibit more storage loss. However, for a given amount of storage loss, nearly the same magnitude of surface subsidence was exhibited, independent of cavern depth.

  1. Risk analyses for disposing nonhazardous oil field wastes in salt caverns

    SciTech Connect (OSTI)

    Tomasko, D.; Elcock, D.; Veil, J.; Caudle, D.

    1997-12-01

    Salt caverns have been used for several decades to store various hydrocarbon products. In the past few years, four facilities in the US have been permitted to dispose nonhazardous oil field wastes in salt caverns. Several other disposal caverns have been permitted in Canada and Europe. This report evaluates the possibility that adverse human health effects could result from exposure to contaminants released from the caverns in domal salt formations used for nonhazardous oil field waste disposal. The evaluation assumes normal operations but considers the possibility of leaks in cavern seals and cavern walls during the post-closure phase of operation. In this assessment, several steps were followed to identify possible human health risks. At the broadest level, these steps include identifying a reasonable set of contaminants of possible concern, identifying how humans could be exposed to these contaminants, assessing the toxicities of these contaminants, estimating their intakes, and characterizing their associated human health risks. The contaminants of concern for the assessment are benzene, cadmium, arsenic, and chromium. These were selected as being components of oil field waste and having a likelihood to remain in solution for a long enough time to reach a human receptor.

  2. Interior cavern conditions and salt fall potential

    SciTech Connect (OSTI)

    Munson, D.E.; Molecke, M.A. [Sandia National Labs., Albuquerque, NM (United States); Myers, R.E. [Strategic Petroleum Reserve, New Orleans, LA (United States)

    1998-03-01

    A relatively large number of salt caverns are used for fluid hydrocarbon storage, including an extensive set of facilities in the Gulf Coast salt domes for the Strategic Petroleum Reserve (SPR) Program. Attention is focused on the SPR caverns because of available histories that detail events involving loss and damage of the hanging string casing. The total number of events is limited, making the database statistically sparse. The occurrence of the events is not evenly distributed, with some facilities, and some caverns, more susceptible than others. While not all of these events could be attributed to impacts from salt falls, many did show the evidence of such impacts. As a result, a study has been completed to analyze the potential for salt falls in the SPR storage caverns. In this process, it was also possible to deduce some of the cavern interior conditions. Storage caverns are very large systems in which many factors could possibly play a part in casing damage. In this study, all of the potentially important factors such as salt dome geology, operational details, and material characteristics were considered, with all being logically evaluated and most being determined as secondary in nature. As a result of the study, it appears that a principal factor in determining a propensity for casing damage from salt falls is the creep and fracture characteristics of salt in individual caverns. In addition the fracture depends strongly upon the concentration of impurity particles in the salt. Although direct observation of cavern conditions is not possible, the average impurity concentration and the accumulation of salt fall material can be determined. When this is done, there is a reasonable correlation between the propensity for a cavern to show casing damage events and accumulation of salt fall material. The accumulation volumes of salt fall material can be extremely large, indicating that only a few of the salt falls are large enough to cause impact damage.

  3. Multiphase Flow and Cavern Abandonment in Salt

    SciTech Connect (OSTI)

    Ehgartner, Brian; Tidwell, Vince

    2001-02-13

    This report will explore the hypothesis that an underground cavity in gassy salt will eventually be gas filled as is observed on a small scale in some naturally occurring salt inclusions. First, a summary is presented on what is known about gas occurrences, flow mechanisms, and cavern behavior after abandonment. Then, background information is synthesized into theory on how gas can fill a cavern and simultaneously displace cavern fluids into the surrounding salt. Lastly, two-phase (gas and brine) flow visualization experiments are presented that demonstrate some of the associated flow mechanisms and support the theory and hypothesis that a cavity in salt can become gas filled after plugging and abandonment

  4. Global Critical Path: A Tool for System-Level Timing Girish Venkataramani

    E-Print Network [OSTI]

    Goldstein, Seth Copen

    Global Critical Path: A Tool for System-Level Timing Analysis Girish Venkataramani Mihai Budiu. Traditionally, the critical path is defined at the RTL level, as the longest path in the combinational logic to define the concept of a Global Critical Path (GCP), for pre- dicting system-level performance. We show

  5. The surface expression of Longhorn Cavern, Burnet County, Texas 

    E-Print Network [OSTI]

    McCaleb, Brenda Denise

    2000-01-01

    This study investigates the surface to subsurface relationship at Longhorn Cavern State Park, which can become one part of an interdisciplinary educational program taught at the park. Longhorn Cavern is located on Backbone Ridge; a wedge shaped...

  6. Analysis of cavern stability at the Bryan Mound SPR site.

    SciTech Connect (OSTI)

    Ehgartner, Brian L.; Sobolik, Steven Ronald

    2009-04-01

    This report presents computational analyses that simulate the structural response of caverns at the Strategic Petroleum Reserve Bryan Mound site. The cavern field comprises 20 caverns. Five caverns (1, 2, 4, and 5; 3 was later plugged and abandoned) were acquired from industry and have unusual shapes and a history dating back to 1946. The other 16 caverns (101-116) were leached according to SPR standards in the mid-1980s and have tall cylindrical shapes. The history of the caverns and their shapes are simulated in a 3-D geomechanics model of the site that predicts deformations, strains, and stresses. Future leaching scenarios due to oil drawdowns using fresh water are also simulated by increasing the volume of the caverns. Cavern pressures are varied in the model to capture operational practices in the field. The results of the finite element model are interpreted to provide information on the current and future status of subsidence, well integrity, and cavern stability. The most significant result in this report is relevant to caverns 1, 2, and 5. The caverns have non-cylindrical shapes and have potential regions where the surrounding salt may be damaged during workover procedures. During a workover the normal cavern operating pressure is lowered to service a well. At this point the wellhead pressures are atmospheric. When the workover is complete, the cavern is repressurized. The resulting elastic stresses are sufficient to cause tension and large deviatoric stresses at several locations. With time, these stresses relax to a compressive state due to salt creep. However, the potential for salt damage and fracturing exists. The analyses predict tensile stresses at locations with sharp-edges in the wall geometry, or in the case of cavern 5, in the neck region between the upper and lower lobes of the cavern. The effects do not appear to be large-scale, however, so the only major impact is the potential for stress-induced salt falls in cavern 5, potentially leading to hanging string damage. Caverns 1 and 2 have no significant issues regarding leachings due to drawdowns; cavern 5 may require a targeted leaching of the neck region to improve cavern stability and lessen hanging string failure potential. The remaining caverns have no significant issues regarding cavern stability and may be safely enlarged during subsequent oil drawdowns. Well strains are significant and consequently future remedial actions may be necessary. Well strains certainly suggest the need for appropriate monitoring through a well-logging program. Subsidence is currently being monitored; there are no issues identified regarding damage from surface subsidence or horizontal strain to surface facilities.

  7. Analysis of cavern shapes for the strategic petroleum reserve.

    SciTech Connect (OSTI)

    Ehgartner, Brian L.; Sobolik, Steven Ronald

    2006-07-01

    This report presents computational analyses to determine the structural integrity of different salt cavern shapes. Three characteristic shapes for increasing cavern volumes are evaluated and compared to the baseline shape of a cylindrical cavern. Caverns with enlarged tops, bottoms, and mid-sections are modeled. The results address pillar to diameter ratios of some existing caverns in the system and will represent the final shape of other caverns if they are repeatedly drawn down. This deliverable is performed in support of the U.S. Strategic Petroleum Reserve. Several three-dimensional models using a close-packed arrangement of 19 caverns have been built and analyzed using a simplified symmetry involving a 30-degree wedge portion of the model. This approach has been used previously for West Hackberry (Ehgartner and Sobolik, 2002) and Big Hill (Park et al., 2005) analyses. A stratigraphy based on the Big Hill site has been incorporated into the model. The caverns are modeled without wells and casing to simplify the calculations. These calculations have been made using the power law creep model. The four cavern shapes were evaluated at several different cavern radii against four design factors. These factors included the dilatant damage safety factor in salt, the cavern volume closure, axial well strain in the caprock, and surface subsidence. The relative performance of each of the cavern shapes varies for the different design factors, although it is apparent that the enlarged bottom design provides the worst overall performance. The results of the calculations are put in the context of the history of cavern analyses assuming cylindrical caverns, and how these results affect previous understanding of cavern behavior in a salt dome.

  8. Test of Department of Energy Strategic Petroleum Reserve Cavern Bryan Mound 104. [Salt cavern entry wells

    SciTech Connect (OSTI)

    Goin, K.L.

    1985-05-01

    This document reports the certification test of Cavern Bryan Mound 104 conducted between September 19 and November 9, 1984. The test included pressurization with oil to near maximum test gradient, depressuring to maximum operating gradient, and doing nitrogen leak tests of the three cavern entry wells. Test results indicate nitrogen loss rates from the wells of 35 bbl/y from 104A, 19 bbl/y from 104B, and 0 bbl/y from 104C. These nitrogen loss rates can reasonably be assumed to correspond to a total cavern oil loss rate of 5.4 bbl/y, which is well within the DOE acceptance criterion of 100 bbl/y of oil per cavern. The final phase of the nitrogen leak test was observed by a representative of the Texas Railroad Commission. 7 refs., 10 figs., 2 tabs.

  9. 3-D Finite Element Analyses of the Egan Cavern Field

    SciTech Connect (OSTI)

    Klamerus, E.W.; Ehgartner, B.L.

    1999-02-01

    Three-dimensional finite element analyses were performed for the two gas-filled storage caverns at the Egan field, Jennings dome, Louisiana. The effects of cavern enlargement on surface subsidence, storage loss, and cavern stability were investigated. The finite element model simulated the leaching of caverns to 6 and 8 billion cubic feet (BCF) and examined their performance at various operating conditions. Operating pressures varied from 0.15 psi/ft to 0.9 psi/ft at the bottom of the lowest cemented casing. The analysis also examined the stability of the web or pillar of salt between the caverns under differential pressure loadings. The 50-year simulations were performed using JAC3D, a three dimensional finite element analysis code for nonlinear quasistatic solids. A damage criterion based on onset of dilatancy was used to evaluate cavern instability. Dilation results from the development of microfractures in salt and, hence, potential increases in permeability onset occurs well before large scale failure. The analyses predicted stable caverns throughout the 50-year period for the range of pressures investigated. Some localized salt damage was predicted near the bottom walls of the caverns if the caverns are operated at minimum pressure for long periods of time. Volumetric cavern closures over time due to creep were moderate to excessive depending on the salt creep properties and operating pressures. However, subsidence above the cavern field was small and should pose no problem, to surface facilities.

  10. A geologic investigation of Longhorn Cavern 

    E-Print Network [OSTI]

    Walters, Victoria Lynn

    1992-01-01

    for this project possible. She provided all the lab facilities necessary to perform uranium and thorium age dating and interpreted the results. She has given me guidance and knowledge through our work together. Ethan Grossman performed the isotopic composition... from fission tracks the amount of uranium in several speleothem samples from Longhorn Cavern. I appreciate all the assistance given to me by many graduate students in the form of field work, lab analysis, construction of the model...

  11. Allowable pillar to diameter ratio for strategic petroleum reserve caverns.

    SciTech Connect (OSTI)

    Ehgartner, Brian L.; Park, Byoung Yoon

    2011-05-01

    This report compiles 3-D finite element analyses performed to evaluate the stability of Strategic Petroleum Reserve (SPR) caverns over multiple leach cycles. When oil is withdrawn from a cavern in salt using freshwater, the cavern enlarges. As a result, the pillar separating caverns in the SPR fields is reduced over time due to usage of the reserve. The enlarged cavern diameters and smaller pillars reduce underground stability. Advances in geomechanics modeling enable the allowable pillar to diameter ratio (P/D) to be defined. Prior to such modeling capabilities, the allowable P/D was established as 1.78 based on some very limited experience in other cavern fields. While appropriate for 1980, the ratio conservatively limits the allowable number of oil drawdowns and hence limits the overall utility and life of the SPR cavern field. Analyses from all four cavern fields are evaluated along with operating experience gained over the past 30 years to define a new P/D for the reserve. A new ratio of 1.0 is recommended. This ratio is applicable only to existing SPR caverns.

  12. Gas-storage calculations yield accurate cavern, inventory data

    SciTech Connect (OSTI)

    Mason, R.G. )

    1990-07-02

    This paper discusses how determining gas-storage cavern size and inventory variance is now possible with calculations based on shut-in cavern surveys. The method is the least expensive of three major methods and is quite accurate when recorded over a period of time.

  13. Feasibility study for lowering the minimum gas pressure in solution-mined caverns based on geomechanical analyses of creep-induced damage and healing

    SciTech Connect (OSTI)

    Ratigan, J.L.; Nieland, J.D.; Devries, K.L.

    1998-12-31

    Geomechanical analyses were made to determine the minimum gas pressure allowable based on an existing stress-based criterion (Damage Potential) and an advanced constitutive model (MDCF model) capable of quantifying the level of damage and healing in rock salt. The MDCF model is a constitutive model developed for the WIPP to provide a continuum description of the dislocation and damage deformation of salt. The purpose of this study was to determine if the MDCF model is applicable for evaluating the minimum gas pressure of CNG storage caverns. Specifically, it was to be determined if this model would predict that the minimum gas pressure in the caverns could be lowered without compromising the stability of the cavern. Additionally, the healing behavior of the salt was analyzed to determine if complete healing of the damaged rock zone would occur during the period the cavern was at maximum gas pressure. Significant findings of this study are reported.

  14. Disposal of oil field wastes into salt caverns: Feasibility, legality, risk, and costs

    SciTech Connect (OSTI)

    Veil, J.A.

    1997-10-01

    Salt caverns can be formed through solution mining in the bedded or domal salt formations that are found in many states. Salt caverns have traditionally been used for hydrocarbon storage, but caverns have also been used to dispose of some types of wastes. This paper provides an overview of several years of research by Argonne National Laboratory on the feasibility and legality of using salt caverns for disposing of oil field wastes, the risks to human populations from this disposal method, and the cost of cavern disposal. Costs are compared between the four operating US disposal caverns and other commercial disposal options located in the same geographic area as the caverns. Argonne`s research indicates that disposal of oil field wastes into salt caverns is feasible and legal. The risk from cavern disposal of oil field wastes appears to be below accepted safe risk thresholds. Disposal caverns are economically competitive with other disposal options.

  15. Oil field waste disposal in salt caverns: An information website

    SciTech Connect (OSTI)

    Tomasko, D.; Veil, J. A.

    1999-12-10

    Argonne National Laboratory has completed the construction of a Website for the US Department of Energy (DOE) that provides detailed information on salt caverns and their use for disposing of nonhazardous oil field wastes (NOW) and naturally occurring radioactive materials (NORM). Specific topics in the Website include the following: descriptions of salt deposits and salt caverns within the US, salt cavern construction methods, potential types of wastes, waste emplacement, regulatory issues, costs, carcinogenic and noncarcinogenic human health risks associated with postulated cavern release scenarios, new information on cavern disposal (e.g., upcoming meetings, regulatory issues, etc.), other studies supported by the National Petroleum Technology Office (NPTO) (e.g., considerations of site location, cavern stability, development issues, and bedded salt characterization in the Midland Basin), and links to other associated Web sites. In addition, the Website allows downloadable access to reports prepared on the topic that were funded by DOE. Because of the large quantities of NOW and NORM wastes generated annually by the oil industry, information presented on this Website is particularly interesting and valuable to project managers, regulators, and concerned citizens.

  16. ADVANCED UNDERGROUND GAS STORAGE CONCEPTS REFRIGERATED-MINED CAVERN STORAGE

    SciTech Connect (OSTI)

    1998-09-01

    Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill-withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. Five regions of the U.S.A. were studied for underground storage development and PB-KBB reviewed the literature to determine if the geology of these regions was suitable for siting hard rock storage caverns. Area gas market conditions in these regions were also studied to determine the need for such storage. Based on an analysis of many factors, a possible site was determined to be in Howard and Montgomery Counties, Maryland. The area has compatible geology and a gas industry infrastructure for the nearby market populous of Baltimore and Washington D.C.. As Gas temperature is lowered, the compressibility of the gas reaches an optimum value. The compressibility of the gas, and the resultant gas density, is a function of temperature and pressure. This relationship can be used to commercial advantage by reducing the size of a storage cavern for a given working volume of natural gas. This study looks at this relationship and and the potential for commercialization of the process in a storage application. A conceptual process design, and cavern design were developed for various operating conditions. Potential site locations were considered and a typical plant layout was developed. In addition a geomechanical review of the proposed cavern design was performed, evaluating the stability of the mine rooms and shafts, and the effects of the refrigerated gas temperatures on the stability of the cavern. Capital and operating cost estimates were also developed for the various temperature cases considered. The cost estimates developed were used to perform a comparative market analysis of this type of gas storage system to other systems that are commercially used in the region of the study.

  17. Solution mining code for studying axisymmetric salt cavern formation

    SciTech Connect (OSTI)

    Russo, A.J.

    1981-09-01

    The solution mining of oil storage caverns in salt domes for the Strategic Petroleum Reserve has prompted the development of a code to predict cavern shape and volume as a function of prescribed flow parameters. Of particular interest is the ability to predict shape changes while leaching is proceeding at the same time the cavern is being filled with oil (leach-fill) and when oil is being withdrawn by fresh water displacement. The theory and overall numerical procedures used in the code development are described. Implicit, finite difference methods are used to solve an axisymmetric mass conservation problem. Calculated results are given which exercise each of the code options and where possible these results are compared with other calculations or available data from solution mining in progress at Bryan Mound, Texas.

  18. Disposal of oil field wastes and NORM wastes into salt caverns.

    SciTech Connect (OSTI)

    Veil, J. A.

    1999-01-27

    Salt caverns can be formed through solution mining in the bedded or domal salt formations that are found in many states. Salt caverns have traditionally been used for hydrocarbon storage, but caverns have also been used to dispose of some types of wastes. This paper provides an overview of several years of research by Argonne National Laboratory on the feasibility and legality of using salt caverns for disposing of nonhazardous oil field wastes (NOW) and naturally occurring radioactive materials (NORM), the risk to human populations from this disposal method, and the cost of cavern disposal. Costs are compared between the four operating US disposal caverns and other commercial disposal options located in the same geographic area as the caverns. Argonne's research indicates that disposal of NOW into salt caverns is feasible and, in most cases, would not be prohibited by state agencies (although those agencies may need to revise their wastes management regulations). A risk analysis of several cavern leakage scenarios suggests that the risk from cavern disposal of NOW and NORM wastes is below accepted safe risk thresholds. Disposal caverns are economically competitive with other disposal options.

  19. Converting LPG caverns to natural-gas storage permits fast response to market

    SciTech Connect (OSTI)

    Crossley, N.G.

    1996-02-19

    Deregulation of Canada`s natural-gas industry in the late 1980s led to a very competitive North American natural-gas storage market. TransGas Ltd., Regina, Sask., began looking for method for developing cost-effective storage while at the same time responding to new market-development opportunities and incentives. Conversion of existing LPG-storage salt caverns to natural-gas storage is one method of providing new storage. To supply SaskEnergy Inc., the province`s local distribution company, and Saskatchewan customers, TransGas previously had developed solution-mined salt storage caverns from start to finish. Two Regina North case histories illustrate TransGas` experiences with conversion of LPG salt caverns to gas storage. This paper provides the testing procedures for the various caverns, cross-sectional diagrams of each cavern, and outlines for cavern conversion. It also lists storage capacities of these caverns.

  20. Dose critical in-vivo detection of anti-cancer drug levels in blood

    DOE Patents [OSTI]

    Miller, Holly H. (Bethel Island, CA); Hirschfeld, deceased, Tomas B. (late of Livermore, CA)

    1991-01-01

    A method and apparatus are disclosed for the in vivo and in vitro detection and measurement of dose critical levels of DNA-binding anti-cancer drug levels in biological fluids. The apparatus comprises a laser based fiber optic sensor (optrode) which utilizes the secondary interactions between the drug and an intercalating fluorochrome bound to a probe DNA, which in turn is attached to the fiber tip at one end thereof. The other end of the optical fiber is attached to an illumination source, detector and recorder. The fluorescence intensity is measured as a function of the drug concentration and its binding constant to the probe DNA. Anticancer drugs which lend themselves to analysis by the use of the method and the optrode of the present invention include doxorubicin, daunorubicin, carminomycin, aclacinomycin, chlorambucil, cyclophosphamide, methotrexate, 5-uracil, arabinosyl cytosine, mitomycin, cis-platinum 11 diamine dichloride procarbazine, vinblastine vincristine and the like. The present method and device are suitable for the continuous monitoring of the levels of these and other anticancer drugs in biological fluids such as blood, serum, urine and the like. The optrode of the instant invention also enables the measurement of the levels of these drugs from a remote location and from multiple samples.

  1. Analysis of SPR salt cavern remedial leach program 2013.

    SciTech Connect (OSTI)

    Weber, Paula D.; Gutierrez, Karen A.; Lord, David L.; Rudeen, David Keith

    2013-09-01

    The storage caverns of the US Strategic Petroleum Reserve (SPR) exhibit creep behavior resulting in reduction of storage capacity over time. Maintenance of oil storage capacity requires periodic controlled leaching named remedial leach. The 30 MMB sale in summer 2011 provided space available to facilitate leaching operations. The objective of this report is to present the results and analyses of remedial leach activity at the SPR following the 2011 sale until mid-January 2013. This report focuses on caverns BH101, BH104, WH105 and WH106. Three of the four hanging strings were damaged resulting in deviations from normal leach patterns; however, the deviations did not affect the immediate geomechanical stability of the caverns. Significant leaching occurred in the toes of the caverns likely decreasing the number of available drawdowns until P/D ratio criteria are met. SANSMIC shows good agreement with sonar data and reasonably predicted the location and size of the enhanced leaching region resulting from string breakage.

  2. Horizontal natural gas storage caverns and methods for producing same

    DOE Patents [OSTI]

    Russo, Anthony (Albuquerque, NM)

    1995-01-01

    The invention provides caverns and methods for producing caverns in bedded salt deposits for the storage of materials that are not solvents for salt. The contemplated salt deposits are of the bedded, non-domed variety, more particularly salt found in layered formations that are sufficiently thick to enable the production of commercially usefully sized caverns completely encompassed by walls of salt of the formation. In a preferred method, a first bore hole is drilled into the salt formation and a cavity for receiving insolubles is leached from the salt formation. Thereafter, at a predetermined distance away from the first bore hole, a second bore hole is drilled towards the salt formation. As this drill approaches the salt, the drill assumes a slant approach and enters the salt and drills through it in a horizontal direction until it intersects the cavity for receiving insolubles. This produces a substantially horizontal conduit from which solvent is controlledly supplied to the surrounding salt formation, leaching the salt and producing a concentrated brine which is removed through the first bore hole. Insolubles are collected in the cavity for receiving insolubles. By controlledly supplying solvent, a horizontal cavern is produced with two bore holes extending therefrom.

  3. Numerical Simulations of Leakage from Underground LPG Storage Caverns

    SciTech Connect (OSTI)

    Yamamoto, Hajime; Pruess, Karsten

    2004-09-01

    To secure a stable supply of petroleum gas, underground storage caverns for liquified petroleum gas (LPG) are commonly used in many countries worldwide. Storing LPG in underground caverns requires that the surrounding rock mass remain saturated with groundwater and that the water pressure be higher than the liquid pressure inside the cavern. In previous studies, gas containment criteria for underground gas storage based on hydraulic gradient and pressure have been discussed, but these studies do not consider the physicochemical characteristics and behavior of LPG such as vaporization and dissolution in groundwater. Therefore, while these studies are very useful for designing storage caverns, they do not provide better understanding of the either the environmental effects of gas contamination or the behavior of vaporized LPG. In this study, we have performed three-phase fluid flow simulations of gas leakage from underground LPG storage caverns, using the multiphase multicomponent nonisothermal simulator TMVOC (Pruess and Battistelli, 2002), which is capable of solving the three-phase nonisothermal flow of water, gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. A two-dimensional cross-sectional model resembling an actual underground LPG facility in Japan was developed, and gas leakage phenomena were simulated for three different permeability models: (1) a homogeneous model, (2) a single-fault model, and (3) a heterogeneous model. In addition, the behavior of stored LPG was studied for the special case of a water curtain suddenly losing its function because of operational problems, or because of long-term effects such as clogging of boreholes. The results of the study indicate the following: (1) The water curtain system is a very powerful means for preventing gas leakage from underground storage facilities. By operating with appropriate pressure and layout, gas containment can be ensured. (2) However , in highly heterogeneous media such as fractured rock and fault zones, local flow paths within which the gas containment criterion is not satisfied could be formed. To eliminate such zones, treatments such as pre/post grouting or an additional installment of water-curtain boreholes are essential. (3) Along highly conductive features such as faults, even partially saturated zones possess certain effects that can retard or prevent gas leakage, while a fully unsaturated fault connected to the storage cavern can quickly cause a gas blowout. This possibility strongly suggests that ensuring water saturation of the rock surrounding the cavern is a very important requirement. (4) Even if an accident should suddenly impair the water curtain, the gas plume does not quickly penetrate the ground surface. In these simulations, the plume takes several months to reach the ground surface.

  4. Fracture and Healing of Rock Salt Related to Salt Caverns

    SciTech Connect (OSTI)

    Chan, K.S.; Fossum, A.F.; Munson, D.E.

    1999-03-01

    In recent years, serious investigations of potential extension of the useful life of older caverns or of the use of abandoned caverns for waste disposal have been of interest to the technical community. All of the potential applications depend upon understanding the reamer in which older caverns and sealing systems can fail. Such an understanding will require a more detailed knowledge of the fracture of salt than has been necessary to date. Fortunately, the knowledge of the fracture and healing of salt has made significant advances in the last decade, and is in a position to yield meaningful insights to older cavern behavior. In particular, micromechanical mechanisms of fracture and the concept of a fracture mechanism map have been essential guides, as has the utilization of continuum damage mechanics. The Multimechanism Deformation Coupled Fracture (MDCF) model, which is summarized extensively in this work was developed specifically to treat both the creep and fracture of salt, and was later extended to incorporate the fracture healing process known to occur in rock salt. Fracture in salt is based on the formation and evolution of microfractures, which may take the form of wing tip cracks, either in the body or the boundary of the grain. This type of crack deforms under shear to produce a strain, and furthermore, the opening of the wing cracks produce volume strain or dilatancy. In the presence of a confining pressure, microcrack formation may be suppressed, as is often the case for triaxial compression tests or natural underground stress situations. However, if the confining pressure is insufficient to suppress fracture, then the fractures will evolve with time to give the characteristic tertiary creep response. Two first order kinetics processes, closure of cracks and healing of cracks, control the healing process. Significantly, volume strain produced by microfractures may lead to changes in the permeability of the salt, which can become a major concern in cavern sealing and operation. The MDCF model is used in three simulations of field experiments in which indirect measures were obtained of the generation of damage. The results of the simulations help to verify the model and suggest that the model captures the correct fracture behavior of rock salt. The model is used in this work to estimate the generation and location of damage around a cylindrical storage cavern. The results are interesting because stress conditions around the cylindrical cavern do not lead to large amounts of damage. Moreover, the damage is such that general failure can not readily occur, nor does the extent of the damage suggest possible increased permeation when the surrounding salt is impermeable.

  5. Preliminary technical and legal evaluation of disposing of nonhazardous oil field waste into salt caverns

    SciTech Connect (OSTI)

    Veil, J.; Elcock, D.; Raivel, M.; Caudle, D.; Ayers, R.C. Jr.; Grunewald, B.

    1996-06-01

    Caverns can be readily formed in salt formations through solution mining. The caverns may be formed incidentally, as a result of salt recovery, or intentionally to create an underground chamber that can be used for storing hydrocarbon products or compressed air or disposing of wastes. The purpose of this report is to evaluate the feasibility, suitability, and legality of disposing of nonhazardous oil and gas exploration, development, and production wastes (hereafter referred to as oil field wastes, unless otherwise noted) in salt caverns. Chapter 2 provides background information on: types and locations of US subsurface salt deposits; basic solution mining techniques used to create caverns; and ways in which salt caverns are used. Later chapters provide discussion of: federal and state regulatory requirements concerning disposal of oil field waste, including which wastes are considered eligible for cavern disposal; waste streams that are considered to be oil field waste; and an evaluation of technical issues concerning the suitability of using salt caverns for disposing of oil field waste. Separate chapters present: types of oil field wastes suitable for cavern disposal; cavern design and location; disposal operations; and closure and remediation. This report does not suggest specific numerical limits for such factors or variables as distance to neighboring activities, depths for casings, pressure testing, or size and shape of cavern. The intent is to raise issues and general approaches that will contribute to the growing body of information on this subject.

  6. Long-term sealing analyses for US Strategic Petroleum Reserve (SPR) caverns

    SciTech Connect (OSTI)

    Ehgartner, B.

    1994-02-01

    It is inevitable that sealing and abandonment will someday occur in a SPR cavern or caverns. To gain insight into the long-term behavior of a typical SPR cavern following sealing and abandonment, a suite of mechanical finite-element calculations was performed. The initial analyses predict how quickly and to what extent a cavern pressurizes after it is plugged. The analyses also examine the stability of the cavern as it changes shape due to the excessive pressures generated as the salt creeps and the brine in the cavern thermally expands. These large-scale analyses do not include the details of the plug but assume a good seal is established in the cavern wells. In another series of analyses, the potential for forming a leak at the plug is evaluated. A cement plug, emplaced in the casing seat of a cavern well, is loaded using the predicted brine pressures from the cavern analyses. The plugged casing analyses examine the potential for forming a leak path in and along the interfaces of salt, casing, and cement plug. In the last set of analysis, the dimensional scale of the problem is further reduced to examine a preexisting crack along a casing/salt interface. The cracked interface is assumed to be fluid filled and fully pressurized by the cavern fluids. The analyses address the potential for the fluid path to extend upwards along a plugged casing should an open microannulus surround the casing after it is plugged.

  7. Sensitivity of storage field performance to geologic and cavern design parameters in salt domes.

    SciTech Connect (OSTI)

    Ehgartner, Brian L.; Park, Byoung Yoon

    2009-03-01

    A sensitivity study was performed utilizing a three dimensional finite element model to assess allowable cavern field sizes for strategic petroleum reserve salt domes. A potential exists for tensile fracturing and dilatancy damage to salt that can compromise the integrity of a cavern field in situations where high extraction ratios exist. The effects of salt creep rate, depth of salt dome top, dome size, caprock thickness, elastic moduli of caprock and surrounding rock, lateral stress ratio of surrounding rock, cavern size, depth of cavern, and number of caverns are examined numerically. As a result, a correlation table between the parameters and the impact on the performance of storage field was established. In general, slower salt creep rates, deeper depth of salt dome top, larger elastic moduli of caprock and surrounding rock, and a smaller radius of cavern are better for structural performance of the salt dome.

  8. STORAGE OF CHILLED NATURAL GAS IN BEDDED SALT STORAGE CAVERNS

    SciTech Connect (OSTI)

    JOel D. Dieland; Kirby D. Mellegard

    2001-11-01

    This report provides the results of a two-phase study that examines the economic and technical feasibility of converting a conventional natural gas storage facility in bedded salt into a refrigerated natural gas storage facility for the purpose of increasing the working gas capacity of the facility. The conceptual design used to evaluate this conversion is based on the design that was developed for the planned Avoca facility in Steuben County, New York. By decreasing the cavern storage temperature from 43 C to -29 C (110 F to -20 F), the working gas capacity of the facility can be increased by about 70 percent (from 1.2 x 10{sup 8} Nm{sup 3} or 4.4 billion cubic feet (Bcf) to 2.0 x 10{sup 8} Nm{sup 3} or 7.5 Bcf) while maintaining the original design minimum and maximum cavern pressures. In Phase I of the study, laboratory tests were conducted to determine the thermal conductivity of salt at low temperatures. Finite element heat transfer calculations were then made to determine the refrigeration loads required to maintain the caverns at a temperature of -29 C (-20 F). This was followed by a preliminary equipment design and a cost analysis for the converted facility. The capital cost of additional equipment and its installation required for refrigerated storage is estimated to be about $13,310,000 or $160 per thousand Nm{sup 3} ($4.29 per thousand cubic feet (Mcf)) of additional working gas capacity. The additional operating costs include maintenance refrigeration costs to maintain the cavern at -29 C (-20 F) and processing costs to condition the gas during injection and withdrawal. The maintenance refrigeration cost, based on the current energy cost of about $13.65 per megawatt-hour (MW-hr) ($4 per million British thermal units (MMBtu)), is expected to be about $316,000 after the first year and to decrease as the rock surrounding the cavern is cooled. After 10 years, the cost of maintenance refrigeration based on the $13.65 per MW-hr ($4 per MMBtu) energy cost is estimated to be $132,000. The gas processing costs are estimated to be $2.05 per thousand Nm{sup 3} ($0.055 per Mcf) of gas injected into and withdrawn from the facility based on the $13.65 per MW-hr ($4 per MMBtu) energy cost. In Phase II of the study, laboratory tests were conducted to determine mechanical properties of salt at low temperature. This was followed by thermomechanical finite element simulations to evaluate the structural stability of the cavern during refrigerated storage. The high thermal expansion coefficient of salt is expected to result in tensile stresses leading to tensile failure in the roof, walls, and floor of the cavern as it is cooled. Tensile fracturing of the cavern roof may result in loss of containment of the gas and/or loss of integrity of the casing shoe, deeming the conversion of this facility not technically feasible.

  9. Bryan Mound SPR cavern 113 remedial leach stage 1 analysis.

    SciTech Connect (OSTI)

    Rudeen, David Keith; Weber, Paula D.; Lord, David L.

    2013-08-01

    The U.S. Strategic Petroleum Reserve implemented the first stage of a leach plan in 2011-2012 to expand storage volume in the existing Bryan Mound 113 cavern from a starting volume of 7.4 million barrels (MMB) to its design volume of 11.2 MMB. The first stage was terminated several months earlier than expected in August, 2012, as the upper section of the leach zone expanded outward more quickly than design. The oil-brine interface was then re-positioned with the intent to resume leaching in the second stage configuration. This report evaluates the as-built configuration of the cavern at the end of the first stage, and recommends changes to the second stage plan in order to accommodate for the variance between the first stage plan and the as-built cavern. SANSMIC leach code simulations are presented and compared with sonar surveys in order to aid in the analysis and offer projections of likely outcomes from the revised plan for the second stage leach.

  10. Stability and support issues in the construction of large span caverns for physics

    SciTech Connect (OSTI)

    Laughton, C.; /Fermilab

    2008-05-01

    New physics experiments, proposed to study neutrinos and protons, call for the use of large underground particle detectors. In the United States, such detectors would be housed in the US Deep Underground Science and Engineering Laboratory (DUSEL), sited within the footprint of the defunct Homestake Mine, South Dakota. Although the experimental proposals differ in detail, all rely heavily upon the ability of the mined and reinforced rock mass to serve as a stable host for the detector facilities. Experimental proposals, based on the use of Water Cherenkov detector technology, specify rock caverns with excavated volumes in excess of half a million cubic meters, spans of at least 50 m, sited at depths of approximately one to 1.5 kilometers. Although perhaps sited at shallower depth, proposals based on the use of Liquid Argon (LAr) detector technology are no less challenging. LAr proposals not only call for the excavation of large span caverns, but have an additional need for the safe management of large quantities (kilo-tonnes) of cryogenic liquid, including critical provisions for the fail-safe egress of underground personnel and the reliable exhaust of Argon gas in the event of a catastrophic release. These multi-year, high value physics experiments will provide the key experimental data needed to support the research of a new generation of physicists as they probe the behavior of basic particles and the fundamental laws of nature. The rock engineer must deliver caverns that will reliably meet operational requirements and remain stable for periods conservatively estimated to be in excess of twenty years. This paper provides an overview of the DUSEL site conditions and discusses key end-user requirements and design criteria likely to dominate in determining the viability of experimental options. The paper stresses the paramount importance of collecting adequate site-specific data to inform early siting, dimensioning and layout decisions. Given the large-scale of the excavation and likely timeline to construction, the paper also strongly suggests that there are exciting opportunities for the rock mechanics and engineering community to identify and efficiently integrate research components into the design and construction process.

  11. Caustic leaching of high-level radioactive tank sludge: A critical literature review

    SciTech Connect (OSTI)

    McGinnis, C.P.; Welch, T.D.; Hunt, R.D.

    1998-08-01

    The Department of Energy (DOE) must treat and safely dispose of its radioactive tank contents, which can be separated into high-level waste (HLW) and low-level waste (LLW) fractions. Since the unit costs of treatment and disposal are much higher for HLW than for LLW, technologies to reduce the amount of HLW are being developed. A key process currently being studied to reduce the volume of HLW sludges is called enhanced sludge washing (ESW). This process removes, by water washes, soluble constituents such as sodium salts, and the washed sludge is then leached with 2--3 M NaOH at 60--100 C to remove nonradioactive metals such as aluminum. The remaining solids are considered to be HLW while the solutions are LLW after radionuclides such as {sup 137}Cs have been removed. Results of bench-scale tests have shown that the ESW will probably remove the required amounts of inert constituents. While both experimental and theoretical results have shown that leaching efficiency increases as the time and temperature of the leach are increased, increases in the caustic concentration above 2--3 M will only marginally improve the leach factors. However, these tests were not designed to validate the assumption that the caustic used in the ESW process will generate only a small increase (10 Mkg) in the amount of LLW; instead the test conditions were selected to maximize leaching in a short period and used more water and caustic than is planned during full-scale operations. Even though calculations indicate that the estimate for the amount of LLW generated by the ESW process appears to be reasonable, a detailed study of the amount of LLW from the ESW process is still required. If the LLW analysis indicates that sodium management is critical, then a more comprehensive evaluation of the clean salt process or caustic recycle would be needed. Finally, experimental and theoretical studies have clearly demonstrated the need for the control of solids formation during and after leaching.

  12. Caustic leaching of high-level radioactive tank sludge: A critical literature review

    SciTech Connect (OSTI)

    McGinnis, C.P.; Welch, T.D.; Hunt, R.D.

    1997-12-31

    The Department of Energy (DOE) must treat and safely dispose of its radioactive tank contents, which can be separated into high-level waste (HLW) and low-level waste (LLW) fractions. Since the unit costs of treatment and disposal are much higher for HLW than for LLW, technologies to reduce the amount of HLW are being developed. A key process currently being studied to reduce the volume of HLW sludges is called enhanced sludge washing (ESW). This process removes, by water washes, soluble constituents such as sodium salts, and the washed sludge is then leached with 2--3 M NaOH at 60--100 C to remove nonradioactive metals such as aluminum. The remaining solids are considered to be HLW while the solutions are LLW after radionuclides such as {sup 137}Cs have been removed. Results of bench-scale tests have shown that the ESW will probably remove the required amounts of inert constituents. While both experimental and theoretical results have shown that leaching efficiency increases as the time and temperature of the leach are increased, increases in the caustic concentration above 2--3 M will only marginally improve the leach factors. However, these tests were not designed to validate the assumption that the caustic used in the ESW process will generate only a small increase (10 Mkg) in the amount of LLW; instead, the test conditions were selected to maximize leaching in a short period and used more water and caustic than is planned during full-scale operations. Even though calculations indicate that the estimate for the amount of LLW generated by the ESW process appears to be reasonable, a detailed study of the amount of LLW from the ESW process is still required. If the LLW analysis indicates that sodium management is critical, then a more comprehensive evaluation of the clean salt process or caustic recycle would be needed. Finally, experimental and theoretical studies have clearly demonstrated the need for the control of solids formation during and after leaching.

  13. Reactor Testing and Qualification: Prioritized High-level Criticality Testing Needs

    SciTech Connect (OSTI)

    S. Bragg-Sitton; J. Bess; J. Werner; G. Harms; S. Bailey

    2011-09-01

    Researchers at the Idaho National Laboratory (INL) were tasked with reviewing possible criticality testing needs to support development of the fission surface power system reactor design. Reactor physics testing can provide significant information to aid in development of technologies associated with small, fast spectrum reactors that could be applied for non-terrestrial power systems, leading to eventual system qualification. Several studies have been conducted in recent years to assess the data and analyses required to design and build a space fission power system with high confidence that the system will perform as designed [Marcille, 2004a, 2004b; Weaver, 2007; Parry et al., 2008]. This report will provide a summary of previous critical tests and physics measurements that are potentially applicable to the current reactor design (both those that have been benchmarked and those not yet benchmarked), summarize recent studies of potential nuclear testing needs for space reactor development and their applicability to the current baseline fission surface power (FSP) system design, and provide an overview of a suite of tests (separate effects, sub-critical or critical) that could fill in the information database to improve the accuracy of physics modeling efforts as the FSP design is refined. Some recommendations for tasks that could be completed in the near term are also included. Specific recommendations on critical test configurations will be reserved until after the sensitivity analyses being conducted by Los Alamos National Laboratory (LANL) are completed (due August 2011).

  14. Advanced Underground Gas Storage Concepts: Refrigerated-Mined Cavern Storage, Final Report

    SciTech Connect (OSTI)

    1998-09-30

    Over the past 40 years, cavern storage of LPG's, petrochemicals, such as ethylene and propylene, and other petroleum products has increased dramatically. In 1991, the Gas Processors Association (GPA) lists the total U.S. underground storage capacity for LPG's and related products of approximately 519 million barrels (82.5 million cubic meters) in 1,122 separate caverns. Of this total, 70 are hard rock caverns and the remaining 1,052 are caverns in salt deposits. However, along the eastern seaboard of the U.S. and the Pacific northwest, salt deposits are not available and therefore, storage in hard rocks is required. Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. Competing methods include LNG facilities and remote underground storage combined with pipeline transportation to the area. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. DOE has identified five regions, that have not had favorable geological conditions for underground storage development: New England, Mid-Atlantic (NY/NJ), South Atlantic (DL/MD/VA), South Atlantic (NC/SC/GA), and the Pacific Northwest (WA/OR). PB-KBB reviewed published literature and in-house databases of the geology of these regions to determine suitability of hard rock formations for siting storage caverns, and gas market area storage needs of these regions.

  15. Nitrogen Monitoring of West Hackberry 117 Cavern Wells.

    SciTech Connect (OSTI)

    Bettin, Giorgia; Lord, David

    2015-02-01

    U.S. Strategic Petroleum Reserve (SPR) oil storage cavern West Hackberry 117 was tested under extended nitrogen monitoring following a successful mechanical integrity test in order to validate a newly developed hydrostatic column model to be used to differentiate between normal "tight" well behavior and small-leak behavior under nitrogen. High resolution wireline pressure and temperature data were collected during the test period and used in conjunction with the hydrostatic column model to predict the nitrogen/oil interface and the pressure along the entire fluid column from the bradenhead flange nominally at ground surface to bottom of brine pool. Results here and for other SPR caverns have shown that wells under long term nitrogen monitoring do not necessarily pressurize with a relative rate (P N2 /P brine) of 1. The theoretical relative pressure rate depends on the well configuration, pressure and the location of the nitrogen-oil interface and varies from well to well. For the case of WH117 the predicted rates were 0.73 for well A and 0.92 for well B. The measured relative pressurization rate for well B was consistent with the model prediction, while well A rate was found to be between 0.58-0.68. A number of possible reasons for the discrepancy between the model and measured rates of well A are possible. These include modeling inaccuracy, measurement inaccuracy or the possibility of the presence of a very small leak (below the latest calculated minimum detectable leak rate).

  16. A NOVEL PROCESS TO USE SALT CAVERNS TO RECEIVE SHIP BORNE LNG

    SciTech Connect (OSTI)

    Michael M. McCall; William M. Bishop; Marcus Krekel; James F. Davis; D. Braxton Scherz

    2005-05-31

    This cooperative research project validates use of man made salt caverns to receive and store the cargoes of LNG ships in lieu of large liquid LNG tanks. Salt caverns will not tolerate direct injection of LNG because it is a cryogenic liquid, too cold for contact with salt. This research confirmed the technical processes and the economic benefits of pressuring the LNG up to dense phase, warming it to salt compatible temperatures and then directly injecting the dense phase gas into salt caverns for storage. The use of salt caverns to store natural gas sourced from LNG imports, particularly when located offshore, provides a highly secure, large scale and lower cost import facility as an alternative to tank based LNG import terminals. This design can unload a ship in the same time as unloading at a tank based terminal. The Strategic Petroleum Reserve uses man made salt caverns to securely store large quantities of crude oil. Similarly, this project describes a novel application of salt cavern gas storage technologies used for the first time in conjunction with LNG receiving. The energy industry uses man made salt caverns to store an array of gases and liquids but has never used man made salt caverns directly in the importation of LNG. This project has adapted and expanded the field of salt cavern storage technology and combined it with novel equipment and processes to accommodate LNG importation. The salt cavern based LNG receiving terminal described in the project can be located onshore or offshore, but the focus of the design and cost estimates has been on an offshore location, away from congested channels and ports. The salt cavern based terminal can provide large volumes of gas storage, high deliverability from storage, and is simplified in operation compared to tank based LNG terminals. Phase I of this project included mathematical modeling that proved a salt cavern based receiving terminal could be built at lower capital cost, and would have significantly higher delivery capacity, shorter construction time, and be much more secure than a conventional liquid tank based terminal. Operating costs of a salt cavern terminal are lower than tank based terminals because ''boil off'' is eliminated and maintenance costs of caverns are lower than LNG tanks. Phase II included the development of offshore mooring designs, wave tank tests, high pressure LNG pump field tests, heat exchanger field tests, and development of a model offshore LNG facility and cavern design. Engineers designed a model facility, prepared equipment lists, and confirmed capital and operating costs. In addition, vendors quoted fabrication and installation costs, confirming that an offshore salt cavern based LNG terminal would have lower capital and operating costs than a similarly sized offshore tank based terminal. Salt cavern storage is infinitely more secure than surface storage tanks, far less susceptible to accidents or purposeful damage, and much more acceptable to the community. More than thirty industry participants provided cost sharing, technical expertise, and guidance in the conduct and evaluation of the field tests, facility design and operating and cost estimates. Their close participation has accelerated the industry's acceptance of the conclusions of this research. The industry participants also developed and submitted several alternative designs for offshore mooring and for high pressure LNG heat exchangers in addition to those that were field tested in this project. HNG Storage, a developer, owner, and operator of natural gas storage facilities, and a participant in the DOE research has announced they will lead the development of the first offshore salt cavern based LNG import facility. Which will be called the Freedom LNG Terminal. It will be located offshore Louisiana, and is expected to be jointly developed with other members of the research group yet to be named. An offshore port license application is scheduled to be filed by fourth quarter 2005 and the terminal could be operational by 2009. This terminal allows the large volume importa

  17. Literature Survey Concerning the Feasibility of Remedial Leach for Select Phase I Caverns

    SciTech Connect (OSTI)

    Weber, Paula D.; Flores, Karen A.; Lord, David L.

    2015-09-01

    Bryan Mound 5 ( BM5 ) and West Hackberry 9 ( WH9 ) have the potential to create a significant amount of new storage space should the caverns be deemed "leach - ready". This study discusses the original drilling history of the caverns, surrounding geology, current stability, and, based on this culmination of data, makes a preliminary assessment of the leach potential for the cavern. The risks associated with leaching BM5 present substantial problems for the SPR . The odd shape and large amount of insoluble material make it difficult to de termine whether a targeted leach would have the desired effect and create useable ullage or further distort the shape with preferential leaching . T he likelihood of salt falls and damaged or severed casing string is significant . In addition, a targeted le ach would require the relocation of approximately 27 MMB of oil . Due to the abundance of unknown factors associated with this cavern, a targeted leach of BM5 is not recommended. A targeted leaching of the neck of WH 9 could potentially eliminate or diminis h the mid - cavern ledge result ing in a more stable cavern with a more favorable shape. A better understanding of the composition of the surrounding salt and a less complicated leaching history yields more confidence in the ability to successfully leach this region. A targeted leach of WH9 can be recommended upon the completion of a full leach plan with consideration of the impacts upon nearby caverns .

  18. Leached salt cavern design using a fracture criterion for rock salt

    SciTech Connect (OSTI)

    Preece, D.S.; Wawersik, W.R.

    1984-01-01

    In 1975 Congress passed the Energy Conservation Act to establish a US Strategic Petroleum Reserve (SPR) with a capacity of 750 million barrels of crude oil. The most economic storage medium was determined to be salt caverns leached in salt domes in Louisiana and Texas. Salt caverns existed at several sites when the reserve was created. These were obtained by the US Department of Energy (DOE) and used to initiate SPR oil storage. In order to meet the storage capacity approved by Congress, new caverns also had to be leached. To support the resulting design effort, finite element computer programs have been used to determine the creep closure and structural stability of salt caverns. Using site specific material properties including creep models, elastic moduli and fracture data, the finite element analyses have been replaced earlier empirical approaches to cavern design. This report presents results of such finite element analyses to determine the best cavern roof shape and the minimum pillar to diameter ratio, P/D. These numerical predictions indicate that the current cavern design is safe. 12 references, 7 figures, 2 tables.

  19. A critical concern for embedded sys tems is the need to deliver high levels of per

    E-Print Network [OSTI]

    Mudge, Trevor

    power through dynamic voltage scaling (DVS). 1 Lowering clock frequency to the minimum required level exploits periods of low proces­ sor utilization and allows a corresponding reduction in supply voltage. Because dynam­ ic energy scales quadratically with supply volt­ age, DVS can significantly reduce

  20. Observations on vapor pressure in SPR caverns : sources.

    SciTech Connect (OSTI)

    Munson, Darrell Eugene

    2010-05-01

    The oil of the Strategic Petroleum Reserve (SPR) represents a national response to any potential emergency or intentional restriction of crude oil supply to this country, and conforms to International Agreements to maintain such a reserve. As assurance this reserve oil will be available in a timely manner should a restriction in supply occur, the oil of the reserve must meet certain transportation criteria. The transportation criteria require that the oil does not evolve dangerous gas, either explosive or toxic, while in the process of transport to, or storage at, the destination facility. This requirement can be a challenge because the stored oil can acquire dissolved gases while in the SPR. There have been a series of reports analyzing in exceptional detail the reasons for the increases, or regains, in gas content; however, there remains some uncertainty in these explanations and an inability to predict why the regains occur. Where the regains are prohibitive and exceed the criteria, the oil must undergo degasification, where excess portions of the volatile gas are removed. There are only two known sources of gas regain, one is the salt dome formation itself which may contain gas inclusions from which gas can be released during oil processing or storage, and the second is increases of the gases release by the volatile components of the crude oil itself during storage, especially if the stored oil undergoes heating or is subject to biological generation processes. In this work, the earlier analyses are reexamined and significant alterations in conclusions are proposed. The alterations are based on how the fluid exchanges of brine and oil uptake gas released from domal salt during solutioning, and thereafter, during further exchanges of fluids. Transparency of the brine/oil interface and the transfer of gas across this interface remains an important unanswered question. The contribution from creep induced damage releasing gas from the salt surrounding the cavern is considered through computations using the Multimechanism Deformation Coupled Fracture (MDCF) model, suggesting a relative minor, but potentially significant, contribution to the regain process. Apparently, gains in gas content can be generated from the oil itself during storage because the salt dome has been heated by the geothermal gradient of the earth. The heated domal salt transfers heat to the oil stored in the caverns and thereby increases the gas released by the volatile components and raises the boiling point pressure of the oil. The process is essentially a variation on the fractionation of oil, where each of the discrete components of the oil have a discrete temperature range over which that component can be volatized and removed from the remaining components. The most volatile components are methane and ethane, the shortest chain hydrocarbons. Since this fractionation is a fundamental aspect of oil behavior, the volatile component can be removed by degassing, potentially prohibiting the evolution of gas at or below the temperature of the degas process. While this process is well understood, the ability to describe the results of degassing and subsequent regain is not. Trends are not well defined for original gas content, regain, and prescribed effects of degassing. As a result, prediction of cavern response is difficult. As a consequence of this current analysis, it is suggested that solutioning brine of the final fluid exchange of a just completed cavern, immediately prior to the first oil filling, should be analyzed for gas content using existing analysis techniques. This would add important information and clarification to the regain process. It is also proposed that the quantity of volatile components, such as methane, be determined before and after any degasification operation.

  1. Mapping critical levels of ozone, sulfur dioxide and nitrogen dioxide for crops, forests and natural vegetation in the United States

    SciTech Connect (OSTI)

    Rosenbaum, B.J.; Strickland, T.C.; McDowell, M.K.

    1994-01-01

    Air pollution abatement strategies for controlling nitrogen dioxide, sulfur dioxide, and ozone emissions in the United States focus on a 'Standards-based' approach. This approach places limits on air pollution by maintaining a baseline value for air quality, no matter what the ecosystem can or cannot withstand. In the paper, the authors present example critical levels maps for the conterminous U.S. developed using the 'effects-based' mapping approach as defined by the United Nations Economic Commission for Europe's Convention on Long-Range Transboundary Air Pollution, Task Force on Mapping. The approach emphasizes the pollution level or load capacity an ecosystem can accommodate before degradation occurs, and allows for analysis of cumulative effects. They present the first stage of an analysis that reports the distribution of exceedances of critical levels for NO2, SO3, and O3 in sensitive forest, crop, and natural vegetation ecosystems in the contiguous United States. They conclude that extrapolation to surrounding geographic areas requires the analysis of diverse and compounding factors that preclude simple extrapolation methods. (Copyright (c) 1994 Kluwer Academic Publishers.)

  2. EXAMINE AND EVALUATE A PROCESS TO USE SALT CAVERNS TO RECEIVE SHIP BORNE LIQUEFIED NATURAL GAS

    SciTech Connect (OSTI)

    Michael M. McCall; William M. Bishop; D. Braxton Scherz

    2003-04-24

    The goal of the U.S. Department of Energy cooperative research project is to define, describe, and validate, a process to utilize salt caverns to receive and store the cargoes of LNG ships. The project defines the process as receiving LNG from a ship, pumping the LNG up to cavern injection pressures, warming it to cavern compatible temperatures, injecting the warmed vapor directly into salt caverns for storage, and distribution to the pipeline network. The performance of work under this agreement is based on U.S. Patent 5,511,905, and other U.S. and Foreign pending patent applications. The cost sharing participants in the research are The National Energy Technology Laboratory (U.S. Department of Energy), BP America Production Company, Bluewater Offshore Production Systems (U.S.A.), Inc., and HNG Storage, L.P. Initial results indicate that a salt cavern based receiving terminal could be built at about half the capital cost, less than half the operating costs and would have significantly higher delivery capacity, shorter construction time, and be much more secure than a conventional liquid tank based terminal. There is a significant body of knowledge and practice concerning natural gas storage in salt caverns, and there is a considerable body of knowledge and practice in handling LNG, but there has never been any attempt to develop a process whereby the two technologies can be combined. Salt cavern storage is infinitely more secure than surface storage tanks, far less susceptible to accidents or terrorist acts, and much more acceptable to the community. The project team developed conceptual designs of two salt cavern based LNG terminals, one with caverns located in Calcasieu Parish Louisiana, and the second in Vermilion block 179 about 50 miles offshore Louisiana. These conceptual designs were compared to conventional tank based LNG terminals and demonstrate superior security, economy and capacity. The potential for the development of LNG receiving terminals, utilizing salt caverns for storage and the existing comprehensive pipeline system has profound implications for the next generation of LNG terminals. LNG imports are expected to become an increasingly more important part of the U.S. energy supply and the capacities to receive LNG securely, safely, and economically must be expanded. Salt cavern LNG receiving terminals both in onshore and offshore locations can be quickly built and provide additional import capacity into the U.S. exceeding 6-10 Bcf/day in the aggregate.

  3. Disposal of NORM-Contaminated Oil Field Wastes in Salt Caverns

    SciTech Connect (OSTI)

    Blunt, D.L.; Elcock, D.; Smith, K.P.; Tomasko, D.; Viel, J.A.; and Williams, G.P.

    1999-01-21

    In 1995, the U.S. Department of Energy (DOE), Office of Fossil Energy, asked Argonne National Laboratory (Argonne) to conduct a preliminary technical and legal evaluation of disposing of nonhazardous oil field waste (NOW) into salt caverns. That study concluded that disposal of NOW into salt caverns is feasible and legal. If caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they can be a suitable means of disposing of NOW (Veil et al. 1996). Considering these findings and the increased U.S. interest in using salt caverns for NOW disposal, the Office of Fossil Energy asked Argonne to conduct further research on the cost of cavern disposal compared with the cost of more traditional NOW disposal methods and on preliminary identification and investigation of the risks associated with such disposal. The cost study (Veil 1997) found that disposal costs at the four permitted disposal caverns in the United States were comparable to or lower than the costs of other disposal facilities in the same geographic area. The risk study (Tomasko et al. 1997) estimated that both cancer and noncancer human health risks from drinking water that had been contaminated by releases of cavern contents were significantly lower than the accepted risk thresholds. Since 1992, DOE has funded Argonne to conduct a series of studies evaluating issues related to management and disposal of oil field wastes contaminated with naturally occurring radioactive material (NORM). Included among these studies were radiological dose assessments of several different NORM disposal options (Smith et al. 1996). In 1997, DOE asked Argonne to conduct additional analyses on waste disposal in salt caverns, except that this time the wastes to be evaluated would be those types of oil field wastes that are contaminated by NORM. This report describes these analyses. Throughout the remainder of this report, the term ''NORM waste'' is used to mean ''oil field waste contaminated by NORM''.

  4. Level density of the Hénon-Heiles system above the critical barrier Energy

    E-Print Network [OSTI]

    M. Brack; J. Kaidel; P. Winkler; S. N. Fedotkin

    2005-11-05

    We discuss the coarse-grained level density of the H\\'enon-Heiles system above the barrier energy, where the system is nearly chaotic. We use periodic orbit theory to approximate its oscillating part semiclassically via Gutzwiller's semiclassical trace formula (extended by uniform approximations for the contributions of bifurcating orbits). Including only a few stable and unstable orbits, we reproduce the quantum-mechanical density of states very accurately. We also present a perturbative calculation of the stabilities of two infinite series of orbits (R$_n$ and L$_m$), emanating from the shortest librating straight-line orbit (A) in a bifurcation cascade just below the barrier, which at the barrier have two common asymptotic Lyapunov exponents $\\chi_{\\rm R}$ and $\\chi_{\\rm L}$.

  5. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    E-Print Network [OSTI]

    Rutqvist, J.

    2013-01-01

    compressed air energy storage (CAES) in lined rock cavernsCompressed Air Energy Storage (CAES) in Lined Rock Cavernscompressed air energy storage (CAES) in concrete-lined rock

  6. The accurate and fast determination of carbon dioxide (CO2) levels is critical for many health and environmental applications. For example, the analysis of CO2 levels in exhaled breath

    E-Print Network [OSTI]

    The accurate and fast determination of carbon dioxide (CO2) levels is critical for many health of the sensor device. Chemical Engineering Doctoral Defense A Novel Handheld Real-time Carbon Dioxide Analyzer

  7. Underground physics without underground labs: large detectors in solution-mined salt caverns

    E-Print Network [OSTI]

    Benjamin Monreal

    2014-09-30

    A number of current physics topics, including long-baseline neutrino physics, proton decay searches, and supernova neutrino searches, hope to someday construct huge (50 kiloton to megaton) particle detectors in shielded, underground sites. With today's practices, this requires the costly excavation and stabilization of large rooms in mines. In this paper, we propose utilizing the caverns created by the solution mining of salt. The challenge is that such caverns must be filled with pressurized fluid and do not admit human access. We sketch some possible methods of installing familiar detector technologies in a salt cavern under these constraints. Some of the detectors discussed are also suitable for deep-sea experiments, discussed briefly. These sketches appear challenging but feasible, and appear to force few major compromises on detector capabilities. This scheme offers avenues for enormous cost savings on future detector megaprojects.

  8. Underground physics without underground labs: large detectors in solution-mined salt caverns

    E-Print Network [OSTI]

    Monreal, Benjamin

    2014-01-01

    A number of current physics topics, including long-baseline neutrino physics, proton decay searches, and supernova neutrino searches, hope to someday construct huge (50 kiloton to megaton) particle detectors in shielded, underground sites. With today's practices, this requires the costly excavation and stabilization of large rooms in mines. In this paper, we propose utilizing the caverns created by the solution mining of salt. The challenge is that such caverns must be filled with pressurized fluid and do not admit human access. We sketch some possible methods of installing familiar detector technologies in a salt cavern under these constraints. Some of the detectors discussed are also suitable for deep-sea experiments, discussed briefly. These sketches appear challenging but feasible, and appear to force few major compromises on detector capabilities. This scheme offers avenues for enormous cost savings on future detector megaprojects.

  9. Preliminary Technical and Legal Evaluation of Disposing of Nonhazardous Oil Field Waste into Salt Caverns

    SciTech Connect (OSTI)

    Ayers, Robert C.; Caudle, Dan; Elcock, Deborah; Raivel, Mary; Veil, John; and Grunewald, Ben

    1999-01-21

    This report presents an initial evaluation of the suitability, feasibility, and legality of using salt caverns for disposal of nonhazardous oil field wastes. Given the preliminary and general nature of this report, we recognize that some of our findings and conclusions maybe speculative and subject to change upon further research on this topic.

  10. Analysis of the Black-Capped Vireo habitat at Kickapoo Caverns State Park, Texas using a Geographic Information System 

    E-Print Network [OSTI]

    Castiaux, Nathalie

    1995-01-01

    A Geographic Information System (GIS) database was developed for Y,-ickapoo Cavern State Park, Tx. The digital database was used to characterize the Black-Capped Vireo ( Vireo Attricapillus Woodhouse) breeding habitat, and to produce a potential...

  11. Commercial potential of natural gas storage in lined rock caverns (LRC)

    SciTech Connect (OSTI)

    1999-11-01

    The geologic conditions in many regions of the United States will not permit the development of economical high-deliverability gas storage in salt caverns. These regions include the entire Eastern Seaboard; several northern states, notably Minnesota and Wisconsin; many of the Rocky Mountain States; and most of the Pacific Northwest. In late 1997, the United States Department of Energy (USDOE) Federal Energy Technology Center engaged Sofregaz US to investigate the commercialization potential of natural gas storage in Lined Rock Caverns (LRC). Sofregaz US teamed with Gaz de France and Sydkraft, who had formed a consortium, called LRC, to perform the study for the USDOE. Underground storage of natural gas is generally achieved in depleted oil and gas fields, aquifers, and solution-mined salt caverns. These storage technologies require specific geologic conditions. Unlined rock caverns have been used for decades to store hydrocarbons - mostly liquids such as crude oil, butane, and propane. The maximum operating pressure in unlined rock caverns is limited, since the host rock is never entirely impervious. The LRC technology allows a significant increase in the maximum operating pressure over the unlined storage cavern concept, since the gas in storage is completely contained with an impervious liner. The LRC technology has been under development in Sweden by Sydkraft since 1987. The development process has included extensive technical studies, laboratory testing, field tests, and most recently includes a storage facility being constructed in southern Sweden (Skallen). The LRC development effort has shown that the concept is technically and economically viable. The Skallen storage facility will have a rock cover of 115 meters (375 feet), a storage volume of 40,000 cubic meters (250,000 petroleum barrels), and a maximum operating pressure of 20 MPa (2,900 psi). There is a potential for commercialization of the LRC technology in the United States. Two regions were studied in some detail - the Northeast and the Southeast. The investment cost for an LRC facility in the Northeast is approximately $182 million and $343 million for a 2.6-billion cubic foot (bcf) working gas facility and a 5.2-bcf working gas storage facility, respectively. The relatively high investment cost is a strong function of the cost of labor in the Northeast. The labor union-related rules and requirements in the Northeast result in much higher underground construction costs than might result in Sweden, for example. The LRC technology gas storage service is compared to other alternative technologies. The LRC technology gas storage service was found to be competitive with other alternative technologies for a variety of market scenarios.

  12. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 1, Bayou Choctaw site, Louisiana.

    SciTech Connect (OSTI)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-10-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 1 focuses on the Bayou Choctaw SPR site, located in southern Louisiana. Volumes 2, 3, and 4, respectively, present images for the Big Hill SPR site, Texas, the Bryan Mound SPR site, Texas, and the West Hackberry SPR site, Louisiana. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  13. Sonar atlas of caverns comprising the U.S. Strategic Petroleum Reserve. Volume 2, Big Hill Site, Texas.

    SciTech Connect (OSTI)

    Rautman, Christopher Arthur; Lord, Anna Snider

    2007-08-01

    Downhole sonar surveys from the four active U.S. Strategic Petroleum Reserve sites have been modeled and used to generate a four-volume sonar atlas, showing the three-dimensional geometry of each cavern. This volume 2 focuses on the Big Hill SPR site, located in southeastern Texas. Volumes 1, 3, and 4, respectively, present images for the Bayou Choctaw SPR site, Louisiana, the Bryan Mound SPR site, Texas, and the West Hackberry SPR site, Louisiana. The atlas uses a consistent presentation format throughout. The basic geometric measurements provided by the down-cavern surveys have also been used to generate a number of geometric attributes, the values of which have been mapped onto the geometric form of each cavern using a color-shading scheme. The intent of the various geometrical attributes is to highlight deviations of the cavern shape from the idealized cylindrical form of a carefully leached underground storage cavern in salt. The atlas format does not allow interpretation of such geometric deviations and anomalies. However, significant geometric anomalies, not directly related to the leaching history of the cavern, may provide insight into the internal structure of the relevant salt dome.

  14. Strategic Petroleum Reserve (SPR) oil storage cavern sulphur mines 2-4-5 certification tests and analysis. Part I: 1981 testing. Part II: 1982 testing

    SciTech Connect (OSTI)

    Beasley, R.R.

    1982-12-01

    Well leak tests and a cavern pressure were conducted in June through December 1981, and are described in Part I. The tests did not indicate conclusively that there was no leakage from the cavern, but the data indicate that cavern structural failure during oil storage is unlikely. The test results indicated that retesting and well workover were desirable prior to making a decision on the cavern use. Well leak tests were conducted in March through May 1982, and are described in Part II. The tests indicated that there was no significant leakage from wells 2 and 4 but that the leakage from wells 2A and 5 exceeded the DOE criterion. Because of the proximity of cavern 2-4-5 to the edge of the salt, this cavern should be considered for only one fill/withdrawal cycle prior to extensive reevaluation. 57 figures, 17 tables.

  15. Estimated human health risks of disposing of nonhazardous oil field waste in salt caverns

    SciTech Connect (OSTI)

    Tomasko, D.; Elcock, D.; Veil, J.

    1997-09-01

    Argonne National Laboratory (ANL) has completed an evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from nonhazardous oil field wastes (NOW) disposed in domal salt caverns. In this assessment, several steps were used to evaluate potential human health risks: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing the contaminants` toxicities, estimating contaminant intakes, and, finally, calculating human cancer and noncancer risks.

  16. A critical concern for embedded sys-tems is the need to deliver high levels of per-

    E-Print Network [OSTI]

    Cafarella, Michael J.

    proces- sor utilization and allows a corresponding reduction in supply voltage. Because dynam- ic energy voltage scaling (DVS).1 Lowering clock frequency to the minimum required level exploits periods of low to run at multiple fre- quency and voltage levels is challenging and requires characterizing

  17. Nearest Neighbor Averaging and its Effect on the Critical Level and Minimum Detectable Concentration for Scanning Radiological Survey Instruments that Perform Facility Release Surveys.

    SciTech Connect (OSTI)

    Fournier, Sean Donovan; Beall, Patrick S [Sandia National Laboratories, Livermore, CA; Miller, Mark L.

    2014-08-01

    Through the SNL New Mexico Small Business Assistance (NMSBA) program, several Sandia engineers worked with the Environmental Restoration Group (ERG) Inc. to verify and validate a novel algorithm used to determine the scanning Critical Level (L c ) and Minimum Detectable Concentration (MDC) (or Minimum Detectable Areal Activity) for the 102F scanning system. Through the use of Monte Carlo statistical simulations the algorithm mathematically demonstrates accuracy in determining the L c and MDC when a nearest-neighbor averaging (NNA) technique was used. To empirically validate this approach, SNL prepared several spiked sources and ran a test with the ERG 102F instrument on a bare concrete floor known to have no radiological contamination other than background naturally occurring radioactive material (NORM). The tests conclude that the NNA technique increases the sensitivity (decreases the L c and MDC) for high-density data maps that are obtained by scanning radiological survey instruments.

  18. An Investigation of the Integrity of Cemented Casing Seals with Application to Salt Cavern Sealing and Abandonment

    SciTech Connect (OSTI)

    Pfeifle, T.W.; Mellegard, K.D.; Skaug, N.T.; Bruno, M.S.

    2001-04-19

    This research project was pursued in three key areas. (1) Salt permeability testing under complex stress states; (2) Hydraulic and mechanical integrity investigations of the well casing shoe through benchscale testing; and (3) Geomechanical modeling of the fluid/salt hydraulic and mechanical interaction of a sealed cavern.

  19. Characterization of bedded salt for storage caverns -- A case study from the Midland Basin, Texas

    SciTech Connect (OSTI)

    Hovorka, Susan D.; Nava, Robin

    2000-06-13

    The geometry of Permian bedding salt in the Midland Basin is a product of interaction between depositional facies and postdepositional modification by salt dissolution. Mapping high-frequency cycle patterns in cross section and map view using wireline logs documents the salt geometry. Geologically based interpretation of depositional and dissolution processes provides a powerful tool for mapping and geometry of salt to assess the suitability of sites for development of solution-mined storage caverns. In addition, this process-based description of salt geometry complements existing data about the evolution of one of the best-known sedimentary basins in the world, and can serve as a genetic model to assist in interpreting other salts.

  20. Exploring the concept of compressed air energy storage (CAES) in lined rock caverns at shallow depth: A modeling study of air tightness and energy balance

    E-Print Network [OSTI]

    Kim, H.-M.

    2012-01-01

    and R. Scharf, Huntroft CAES: More than 20 years ofbase case for modeling of CAES in a lined rock cavern. TableFigure 2. Components of a CAES system (modified from http://

  1. Critical Materials:

    Office of Environmental Management (EM)

    Extraction Separation Processes for Critical Materials in 30- 21 Stage Test Facility (Bruce Moyer) ......

  2. Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in lined rock caverns

    SciTech Connect (OSTI)

    Rutqvist, J.; Kim, H. -M.; Ryu, D. -W.; Synn, J. -H.; Song, W. -K.

    2012-02-01

    We applied coupled nonisothermal, multiphase fluid flow and geomechanical numerical modeling to study the coupled thermodynamic and geomechanical performance of underground compressed air energy storage (CAES) in concrete-lined rock caverns. The paper focuses on CAES in lined caverns at relatively shallow depth (e.g., 100 m depth) in which a typical CAES operational pressure of 5 to 8 MPa is significantly higher than both ambient fluid pressure and in situ stress. We simulated a storage operation that included cyclic compression and decompression of air in the cavern, and investigated how pressure, temperature and stress evolve over several months of operation. We analyzed two different lining options, both with a 50 cm thick low permeability concrete lining, but in one case with an internal synthetic seal such as steel or rubber. For our simulated CAES system, the thermodynamic analysis showed that 96.7% of the energy injected during compression could be recovered during subsequent decompression, while 3.3% of the energy was lost by heat conduction to the surrounding media. Our geomechanical analysis showed that tensile effective stresses as high as 8 MPa could develop in the lining as a result of the air pressure exerted on the inner surface of the lining, whereas thermal stresses were relatively smaller and compressive. With the option of an internal synthetic seal, the maximum effective tensile stress was reduced from 8 to 5 MPa, but was still in substantial tension. We performed one simulation in which the tensile tangential stresses resulted in radial cracks and air leakage though the lining. This air leakage, however, was minor (about 0.16% of the air mass loss from one daily compression) in terms of CAES operational efficiency, and did not significantly impact the overall energy balance of the system. However, despite being minor in terms of energy balance, the air leakage resulted in a distinct pressure increase in the surrounding rock that could be quickly detected using pressure monitoring outside the concrete lining.

  3. Long-Term Outcomes of Stereotactic Radiosurgery for Treatment of Cavernous Sinus Meningiomas

    SciTech Connect (OSTI)

    Santos, Marcos Antonio dos, E-mail: marcosrxt@gmail.com [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Bustos Perez de Salcedo, Jose; Gutierrez Diaz, Jose Angel [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain); Calvo, Felipe A. [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Department of Oncology, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Samblas, Jose [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain); Marsiglia, Hugo [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Sallabanda, Kita [Radiotherapy Department, Instituto Madrileno de Oncologia/Grupo IMO, Madrid (Spain); Neurosurgery Department, Sanatorio San Francisco de Asis, Madrid (Spain)

    2011-12-01

    Purpose: Patients with cavernous sinus meningiomas (CSM) have an elevated risk of surgical morbidity and mortality. Recurrence is often observed after partial resection. Stereotactic radiosurgery (SRS), either alone or combined with surgery, represents an important advance in CSM management, but long-term results are lacking. Methods and Materials: A total of 88 CSM patients, treated from January 1991 to December 2005, were retrospectively reviewed. The mean follow-up was 86.8 months (range, 17.1-179.4 months). Among the patients, 22 were followed for more than 10 years. There was a female predominance (84.1%). The age varied from 16 to 90 years (mean, 51.6). In all, 47 patients (53.4%) received SRS alone, and 41 patients (46.6%) had undergone surgery before SRS. A dose of 14 Gy was prescribed to isodose curves from 50% to 90%. In 25 patients (28.4%), as a result of the proximity to organs at risk, the prescribed dose did not completely cover the target. Results: After SRS, 65 (73.8%) patients presented with tumor volume reduction; 14 (15.9%) remained stable, and 9 (10.2%) had tumor progression. The progression-free survival was 92.5% at 5 years, and 82.5% at 10 years. Age, sex, maximal diameter of the treated tumor, previous surgery, and complete target coverage did not show significant associations with prognosis. Among the 88 treated patients, 17 experienced morbidity that was related to SRS, and 6 of these patients spontaneously recovered. Conclusions: SRS is an effective and safe treatment for CSM, feasible either in the primary or the postsurgical setting. Incomplete coverage of the target did not worsen outcomes. More than 80% of the patients remained free of disease progression during long-term follow-up.

  4. Matching field effects at tesla-level magnetic fields in critical current density in high-Tc superconductors containing self-assembled columnar defects

    SciTech Connect (OSTI)

    Sinclair, J. [University of Tennessee, Knoxville (UTK); Zuev, Yuri L [ORNL; Cantoni, Claudia [ORNL; Wee, Sung Hun [ORNL; Varanasi, C. V. [University of Dayton Research Institute; Thompson, James R [ORNL; Christen, David K [ORNL

    2012-01-01

    We have investigated the superconductive transport properties of YBa2Cu3O7 films containing self-assembled columnar arrays of second phase SrZrO3 or BaSnO3 precipitates. A matching condition between columnar pinning sites (aligned at or near the c axis) and external magnetic flux, tilted with respect to them, is identified in the critical current JC.H/ data. The results for the material containing SrZrO3-based pins are analyzed within a simple intuitive model. At matching, the critical current is enhanced above the model prediction. In complementary contact-free investigations of BaSnO3-doped material, matching effects are observed over a wide range of temperatures in the field dependence of JC.H/. The deduced matching fields agree reasonably well with the densities of columnar pins directly observed by scanning electron microscopy.

  5. Criticality Model

    SciTech Connect (OSTI)

    A. Alsaed

    2004-09-14

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of this analysis is to document the criticality computational method. The criticality computational method will be used for evaluating the criticality potential of configurations of fissionable materials (in-package and external to the waste package) within the repository at Yucca Mountain, Nevada for all waste packages/waste forms. The criticality computational method is also applicable to preclosure configurations. The criticality computational method is a component of the methodology presented in ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003). How the criticality computational method fits in the overall disposal criticality analysis methodology is illustrated in Figure 1 (YMP 2003, Figure 3). This calculation will not provide direct input to the total system performance assessment for license application. It is to be used as necessary to determine the criticality potential of configuration classes as determined by the configuration probability analysis of the configuration generator model (BSC 2003a).

  6. Costs for off-site disposal of nonhazardous oil field wastes: Salt caverns versus other disposal methods

    SciTech Connect (OSTI)

    Veil, J.A.

    1997-09-01

    According to an American Petroleum Institute production waste survey reported on by P.G. Wakim in 1987 and 1988, the exploration and production segment of the US oil and gas industry generated more than 360 million barrels (bbl) of drilling wastes, more than 20 billion bbl of produced water, and nearly 12 million bbl of associated wastes in 1985. Current exploration and production activities are believed to be generating comparable quantities of these oil field wastes. Wakim estimates that 28% of drilling wastes, less than 2% of produced water, and 52% of associated wastes are disposed of in off-site commercial facilities. In recent years, interest in disposing of oil field wastes in solution-mined salt caverns has been growing. This report provides information on the availability of commercial disposal companies in oil-and gas-producing states, the treatment and disposal methods they employ, and the amounts they charge. It also compares cavern disposal costs with the costs of other forms of waste disposal.

  7. Critical function and success path summary display

    DOE Patents [OSTI]

    Scarola, Kenneth (Windsor, CT); Jamison, David S. (Windsor, CT); Manazir, Richard M. (North Canton, CT); Rescorl, Robert L. (Vernon, CT); Harmon, Daryl L. (Enfield, CT)

    1995-01-01

    The content of and hierarchical access to three levels of display pages containing information on critical function monitoring and success path monitoring.

  8. Critical Materials Institute

    ScienceCinema (OSTI)

    Alex King

    2013-06-05

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  9. Estimation of low energy neutron flux ($E_n\\leq15$ MeV) in India-based Neutrino Observatory cavern using Monte Carlo techniques

    E-Print Network [OSTI]

    Dokania, N; Mathimalar, S; Garai, A; Nanal, V; Pillay, R G; Bhushan, K G

    2015-01-01

    The neutron flux at low energy ($E_n\\leq15$ MeV) resulting from the radioactivity of the rock in the underground cavern of the India-based Neutrino Observatory is estimated using Geant4-based Monte Carlo simulations. The neutron production rate due to the spontaneous fission of U, Th and ($\\alpha, n$) interactions in the rock is determined employing the actual rock composition. It has been demonstrated that the total flux is equivalent to a finite size cylindrical rock ($D=L=140$ cm) element. The energy integrated neutron flux thus obtained at the center of the underground tunnel is 2.76 (0.47) $\\times 10^{-6}\\rm~n ~cm^{-2}~s^{-1}$. The estimated neutron flux is of the same order ($\\sim10^{-6}\\rm~n ~cm^{-2}~s^{-1}$)~as measured in other underground laboratories.

  10. Estimation of low energy neutron flux ($E_n\\leq15$ MeV) in India-based Neutrino Observatory cavern using Monte Carlo techniques

    E-Print Network [OSTI]

    N. Dokania; V. Singh; S. Mathimalar; A. Garai; V. Nanal; R. G. Pillay; K. G. Bhushan

    2015-09-23

    The neutron flux at low energy ($E_n\\leq15$ MeV) resulting from the radioactivity of the rock in the underground cavern of the India-based Neutrino Observatory is estimated using Geant4-based Monte Carlo simulations. The neutron production rate due to the spontaneous fission of U, Th and ($\\alpha, n$) interactions in the rock is determined employing the actual rock composition. It has been demonstrated that the total flux is equivalent to a finite size cylindrical rock ($D=L=140$ cm) element. The energy integrated neutron flux thus obtained at the center of the underground tunnel is 2.76 (0.47) $\\times 10^{-6}\\rm~n ~cm^{-2}~s^{-1}$. The estimated neutron flux is of the same order ($\\sim10^{-6}\\rm~n ~cm^{-2}~s^{-1}$)~as measured in other underground laboratories.

  11. Critical behavior in topological ensembles

    E-Print Network [OSTI]

    K. Bulycheva; A. Gorsky; S. Nechaev

    2015-02-11

    We consider the relation between three physical problems: 2D directed lattice random walks, ensembles of $T_{n,n+1}$ torus knots, and instanton ensembles in 5D SQED with one compact dimension in $\\Omega$ background and with 5D Chern-Simons term at the level one. All these ensembles exhibit the critical behavior typical for the "area+length+corners" statistics of grand ensembles of 2D directed paths. Using the combinatorial description, we obtain an explicit expression of the generating function for $q$-Narayana numbers which amounts to the new critical behavior in the ensemble of $T_{n,n+1}$ torus knots and in the ensemble of instantons in 5D SQED. Depending on the number of the nontrivial fugacities, we get either the critical point, or cascade of critical lines and critical surfaces. In the 5D gauge theory the phase transition is of the 3rd order, while in the ensemble of paths and ensemble of knots it is typically of the 1st order. We also discuss the relation with the integrable models.

  12. Critical Materials Workshop

    Broader source: Energy.gov [DOE]

    AMO hosted a public workshop on Tuesday, April 3, 2012 in Arlington, VA to provide background information on critical materials assessment, the current research within DOE related to critical...

  13. Criticality assessment of LLRWDF closure

    SciTech Connect (OSTI)

    Sarrack, A.G.; Weber, J.H.; Woody, N.D.

    1992-10-06

    During the operation of the Low Level Radioactive Waste Disposal Facility (LLRWDF), large amounts (greater than 100 kg) of enriched uranium (EU) were buried. This EU came primarily from the closing and decontamination of the Naval Fuels Facility in the time period from 1987--1989. Waste Management Operations (WMO) procedures were used to keep the EU boxes separated to prevent possible criticality during normal operation. Closure of the LLRWDF is currently being planned, and waste stabilization by Dynamic Compaction (DC) is proposed. Dynamic compaction will crush the containers in the LLRWDF and result in changes in their geometry. Research of the LLRWDF operations and record keeping practices have shown that the EU contents of trenches are known, but details of the arrangement of the contents cannot be proven. Reviews of the trench contents, combined with analysis of potential critical configurations, revealed that some portions of the LLRWDF can be expected to be free of criticality concerns while other sections have credible probabilities for the assembly of a critical mass, even in the uncompacted configuration. This will have an impact on the closure options and which trenches can be compacted.

  14. Criticality Model Report

    SciTech Connect (OSTI)

    J.M. Scaglione

    2003-03-12

    The purpose of the ''Criticality Model Report'' is to validate the MCNP (CRWMS M&O 1998h) code's ability to accurately predict the effective neutron multiplication factor (k{sub eff}) for a range of conditions spanned by various critical configurations representative of the potential configurations commercial reactor assemblies stored in a waste package may take. Results of this work are an indication of the accuracy of MCNP for calculating eigenvalues, which will be used as input for criticality analyses for spent nuclear fuel (SNF) storage at the proposed Monitored Geologic Repository. The scope of this report is to document the development and validation of the criticality model. The scope of the criticality model is only applicable to commercial pressurized water reactor fuel. Valid ranges are established as part of the validation of the criticality model. This model activity follows the description in BSC (2002a).

  15. Transport at criticality

    E-Print Network [OSTI]

    A. Buchel; C. Pagnutti

    2009-12-16

    We study second order phase transitions in non-conformal holographic models of gauge theory/string theory correspondence at finite temperature and zero chemical potential. We compute critical exponents of the bulk viscosity near the transition and interpret our results in the framework of available models of dynamical critical phenomena. Intriguingly, although some of the models we discuss belong to different static universality classes, they appear to share the same dynamical critical exponent.

  16. Critical Materials Workshop

    Broader source: Energy.gov (indexed) [DOE]

    Critical Materials Workshop U.S. Department of Energy April 3, 2012 eere.energy.gov Dr. Leo Christodoulou Program Manager Advanced Manufacturing Office Energy Efficiency and...

  17. Reference handbook: Nuclear criticality

    SciTech Connect (OSTI)

    Not Available

    1991-12-06

    The purpose for this handbook is to provide Rocky Flats personnel with the information necessary to understand the basic principles underlying a nuclear criticality.

  18. Modeling the Global Critical Path in Concurrent Systems

    E-Print Network [OSTI]

    Modeling the Global Critical Path in Concurrent Systems Girish Venkataramani Tiberiu Chelcea Mihai Molecular Electronics, under contract number CCR0205523. #12;Keywords: Performance modeling, critical path analysis, high-level synthesis #12;Abstract We show how the global critical path can be used as a practical

  19. CAP: Criticality AnCAP: Criticality An Efficient Speculatip

    E-Print Network [OSTI]

    Torrellas, Josep

    - Tracks running tasks andg their context Novel components of CAPNovel components of CAP - Critical path builder Builds path and analyzes graph - Critical path predictor #12;CAP OvCAP Ov T ll t th hTo collect the critical path calculation is easyp y o find critical path #12;Critical PatCritical Pat T i i l l t d

  20. Vulnerability of critical infrastructures : identifying critical nodes.

    SciTech Connect (OSTI)

    Cox, Roger Gary; Robinson, David Gerald

    2004-06-01

    The objective of this research was the development of tools and techniques for the identification of critical nodes within critical infrastructures. These are nodes that, if disrupted through natural events or terrorist action, would cause the most widespread, immediate damage. This research focuses on one particular element of the national infrastructure: the bulk power system. Through the identification of critical elements and the quantification of the consequences of their failure, site-specific vulnerability analyses can be focused at those locations where additional security measures could be effectively implemented. In particular, with appropriate sizing and placement within the grid, distributed generation in the form of regional power parks may reduce or even prevent the impact of widespread network power outages. Even without additional security measures, increased awareness of sensitive power grid locations can provide a basis for more effective national, state and local emergency planning. A number of methods for identifying critical nodes were investigated: small-world (or network theory), polyhedral dynamics, and an artificial intelligence-based search method - particle swarm optimization. PSO was found to be the only viable approach and was applied to a variety of industry accepted test networks to validate the ability of the approach to identify sets of critical nodes. The approach was coded in a software package called Buzzard and integrated with a traditional power flow code. A number of industry accepted test networks were employed to validate the approach. The techniques (and software) are not unique to power grid network, but could be applied to a variety of complex, interacting infrastructures.

  1. Must Criticism Be Constructive?

    E-Print Network [OSTI]

    Geuss, Raymond

    2012-10-01

    ’ criti - cism is somehow defective, objectionable, or inappropriate. It is part of the responsibility of a critic, it is assumed, not simply to denigrate some institution, social arrangement, or form of action, but to do so while pro- viding at least... to the third of my three dimensions. In cases of ‘full-blown’ criticism the first and second of these aspects are explicitly connected. I would not usually think I had in front of me a case of ‘criti - cism’ — or at any rate of ‘criticism’ in the full...

  2. Critical Materials Hub

    Broader source: Energy.gov [DOE]

    Critical materials, including some rare earth elements that possess unique magnetic, catalytic, and luminescent properties, are key resources needed to manufacture products for the clean energy economy. These materials are so critical to the technologies that enable wind turbines, solar panels, electric vehicles, and energy-efficient lighting that DOE's 2010 and 2011 Critical Materials Strategy reported that supply challenges for five rare earth metals—dysprosium, neodymium, terbium, europium, and yttrium—could affect clean energy technology deployment in the coming years.1, 2

  3. The Critical Materials Institute | Critical Materials Institute

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopment TopMetathesisSediments and Related J. BennettThe Critical

  4. Critical Materials Workshop Agenda

    Broader source: Energy.gov (indexed) [DOE]

    Critical Materials Workshop Sheraton Crystal City 1800 Jefferson Davis Highway, Arlington, VA April 3, 2012, 8 am - 5 pm Time (EDT) Activity Speaker 8:00 am - 9:00 am Registration...

  5. CRITICAL MATERIALS INSTITUTE PROJECTS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    INL National Technology Roadmap for Critical Materials 4 4-3 4.3.3 McCall, Scott LLNL Additive Manufacturing of Permanent Magnets 2 2-1 2.1.2 Turchi, Patrice LLNL Materials...

  6. Critical thickness in silicone thermosets

    E-Print Network [OSTI]

    Deopura, Manish, 1975-

    2005-01-01

    Critical thickness effects are utilized to achieve high fracture toughness in brittle polymers. The postulate of critical thickness, which is: "Macroscopically brittle polymers deform in a ductile fashion below a critical ...

  7. Criticality Safety | Department of Energy

    Office of Environmental Management (EM)

    Nuclear Safety Management American Nuclear Society, Nuclear Criticality Safety Division ANSIANS-8 Standards U.S. Department of Energy Nuclear Criticality Safety Program Orders,...

  8. AVLIS Criticality risk assessment

    SciTech Connect (OSTI)

    Brereton, S.J., LLNL

    1998-04-29

    Evaluation of criticality safety has become an important task in preparing for the Atomic Vapor Laser Isotope Separation (AVLIS) uranium enrichment runs that will take place during the Integrated Process Demonstration (IPD) at Lawrence Livermore National Laboratory (LLNL). This integrated operation of AVLIS systems under plant-like conditions will be used to verify the performance of process equipment and to demonstrate the sustained integrated enrichment performance of these systems using operating parameters that are similar to production plant specifications. Because of the potential criticality concerns associated with enriched uranium, substantial effort has been aimed towards understanding the potential system failures of interest from a criticality standpoint, and evaluating them in detail. The AVLIS process is based on selective photoionization of uranium atoms of atomic weight 235 (U-235) in a vapor stream, followed by electrostatic extraction. The process is illustrated in Figure 1. Two major subsystems are involved: the uranium separator and the laser system. In the separator, metallic uranium is fed into a crucible where it is heated and vaporized by an electron beam. The atomic U-235/U-238 vapor stream moves away from the molten uranium and is illuminated by precisely tuned beams of dye laser light. Upon absorption of the tuned dye laser light, the U-235 atoms become excited and eject electrons (become photoionized), giving them a net positive charge. The ions of U-235 are moved preferentially by an electrostatic field to condense on the product collector, forming the enriched uranium product. The remaining vapor, which is depleted in U-235 (tails), passes unaffected through the photoionization/extractor zone and accumulates on collectors in the top of the separator. Tails and product collector surfaces operate at elevated temperatures so that deposited materials flow as segregated liquid streams. The separated uranium condensates (uranium enriched in U-235 and uranium depleted in U-235) are cooled and accumulated in solid metallic form in canisters. The collected product and tails material is weighed and transferred into certified, critically safe, shipping containers (DOT specification 6M with 2R containment vessel). These will be temporarily stored, and then shipped offsite either for use by a fuel fabricator, or for disposal. Tails material will be packaged for disposal. A criticality risk assessment was performed for AVLIS IPD runs. In this analysis, the likelihood of occurrence of a criticality was examined. For the AVLIS process, there are a number of areas that have been specifically examined to assess whether or not the frequency of occurrence of a criticality is credible (frequency of occurrence > 10-6/yr). In this paper, we discuss only two of the areas: the separator and canister operations.

  9. ON CRITICAL STATE TRANSITIONS BETWEEN DIFFERENT LEVELS IN NEURAL SYSTEMS

    E-Print Network [OSTI]

    WERNER, GERHARD

    2009-01-01

    Higher Cognitive Functions was provided by World Scientific.Access to World Scientific is possible through the

  10. Steady water waves with multiple critical layers: interior dynamics

    E-Print Network [OSTI]

    Mats Ehrnström; Joachim Escher; Gabriele Villari

    2011-04-01

    We study small-amplitude steady water waves with multiple critical layers. Those are rotational two-dimensional gravity-waves propagating over a perfect fluid of finite depth. It is found that arbitrarily many critical layers with cat's-eye vortices are possible, with different structure at different levels within the fluid. The corresponding vorticity depends linearly on the stream function.

  11. Body Dissatisfaction, Weight Criticism, and Self-Reported Physical Activity in Preadolescent Children

    E-Print Network [OSTI]

    Jensen, Chad David

    2008-05-29

    . Girls who reported experiencing high levels of weight criticism and high body dissatisfaction engaged in significantly fewer vigorous activities than peers who experienced criticism in the absence of body dissatisfaction. These findings highlight...

  12. Critical gradient for internal erosion in earthen d ams : a comparative analysis of two predictive methodologies

    E-Print Network [OSTI]

    Donohue, Catherine, M. Eng. Massachusetts Institute of Technology

    2013-01-01

    Minimizing the uncertainty in predicting the critical gradient of a dam (i.e. the critical reservoir pool level) is important during the risk analysis of dams. Uncertainty leads to inexact relative risk in portfolio ...

  13. COVARIANCE PLASTICITY AND REGULATED CRITICALITY

    E-Print Network [OSTI]

    Lehmann, Daniel

    COVARIANCE PLASTICITY AND REGULATED CRITICALITY Elie Bienenstock Division of Applied Mathematics plasticity may cause the brain to operate near criticality. We analyze the effect of such a regulation of Hebbian covariance plasticity. Such a regulation may bring the system near criticality. We suggest

  14. Safety-Critical Universit at

    E-Print Network [OSTI]

    Peleska, Jan - Fachbereich 3

    . Hazard Analysis and Risk Assessment 5. Design Criteria for Safety-Critical Systems 6. Validation, Veri#12. Hazard Analysis and Risk Assessment 5. Design Criteria for Safety-Critical Systems 6. Validation, Veri#12Safety-Critical Systems Prof. Dr. Jan Peleska Universit at Bremen | TZI Dr. Ing. Cornelia Zahlten

  15. Electrostatic interactions in critical solvents

    E-Print Network [OSTI]

    Markus Bier; Andrea Gambassi; Martin Oettel; S. Dietrich

    2011-04-29

    The subtle interplay between critical phenomena and electrostatics is investigated by considering the effective force acting on two parallel walls confining a near-critical binary liquid mixture with added salt. The ion-solvent coupling can turn a non-critical repulsive electrostatic force into an attractive one upon approaching the critical point. However, the effective force is eventually dominated by the critical Casimir effect, the universal properties of which are not altered by the presence of salt. This observation allows a consistent interpretation of recent experimental data.

  16. Teaching Critical Thinking

    E-Print Network [OSTI]

    Holmes, N G; Bonn, D A

    2015-01-01

    The ability to make decisions based on data, with its inherent uncertainties and variability, is a complex and vital skill in the modern world. The need for such quantitative critical thinking occurs in many different contexts, and while it is an important goal of education, that goal is seldom being achieved. We argue that the key element for developing this ability is repeated practice in making decisions based on data, with feedback on those decisions. We demonstrate a structure for providing suitable practice that can be applied in any instructional setting that involves the acquisition of data and relating that data to scientific models. This study reports the results of applying that structure in an introductory physics lab course. Students in an experimental condition were repeatedly instructed to make and act on quantitative comparisons between datasets, and between data and models, an approach that is common to all science disciplines. These instructions were slowly faded across the course. After the...

  17. Infusing Critical Thinking Skill Compare and Contrast into Content of Data Structures Course

    E-Print Network [OSTI]

    Faisal, Kanaan Abed

    Infusing Critical Thinking Skill Compare and Contrast into Content of Data Structures Course M of our efforts in infusing the critical thinking skill of comparing and contrasting into a course on data in the course content of computer curricula at tertiary level. It is expected that infusion of critical thinking

  18. Analysis of SP-100 critical experiments

    SciTech Connect (OSTI)

    Sapir, J.L.; Brandon, D.I.; Collins, P.J.; Cowan, C.L.; Porter, C.A.; Andre, S.V.

    1988-01-01

    In support of the SP-100 space nuclear power source program, preliminary critical benchmark experiments were performed at the ZPPR facility at ANL-W. These configurations are representative of small, fast-spectrum, BeO-reflected, liquid metal-cooled space reactor designs at a 300-kWe power level. Analyses were performed using MCNP (Monte Carlo) and TWODANT (discrete ordinates) transport codes to calculate system criticality, control worth, and power distribution. Both methods calculated eigenvalues within 0.5% of the experimental results. Internal-poison-rod worth was underpredicted and radial reflector worth was overpredicted by both codes by up to 20%. MCNP-calculated control drum worths were underestimated by approximately 8%. Good agreement with experimental values was observed for /sup 235/U fission and for /sup 238/U fission and capture rates with the best agreement occurring in the fuel region and slightly poorer predictions apparent near BeO moderator. 7 refs., 12 figs.

  19. SHEBA-II as a criticality safety benchmark experiment

    SciTech Connect (OSTI)

    LaBauve, R.J.; Sapir, J.L.

    1995-07-01

    SHEBA-II (Solution High Energy Burst Assembly-II) is a critical assembly experiment currently (1995) being operated at the Los Alamos Critical Experiments Facility. It is a bare assembly fueled with an aqueous solution of about 5% enriched uranyl fluoride that is stored in four critically safe steel tanks. The solution is transferred to the critical assembly vessel (CAV) by applying gas pressure to the storage tanks. Reactivity is controlled by varying the solution level, and a safety rod may be inserted in a thimble along the central axis of the CAV for fast shutdown. The simple geometry provided by this cylindrical system allows for easily applied calculational methods, and thus SHEBA-II is ideally suited for use as a criticality safety benchmark experiment.

  20. X(5) Critical-Point Structure in a Finite System

    E-Print Network [OSTI]

    A. Leviatan

    2005-09-01

    X(5) is a paradigm for the structure at the critical point of a particular first-order phase transition for which the intrinsic energy surface has two degenerate minima separated by a low barrier. For a finite system, we show that the dynamics at such a critical point can be described by an effective deformation determined by minimizing the energy surface after projection onto angular momentum zero, and combined with two-level mixing. Wave functions of a particular analytic form are used to derive estimates for energies and quadrupole rates at the critical point.

  1. The Relationships of Media, Task, Spatial Presence, and Critical Thinking, in an Online Tutorial Designed to Teach Art Criticism 

    E-Print Network [OSTI]

    Wood, Nancy O

    2013-11-08

    THE RELATIONSHIPS OF MEDIA, TASK, SPATIAL PRESENCE, AND CRITICAL THINKING, IN AN ONLINE TUTORIAL DESIGNED TO TEACH ART CRITICISM A Dissertation by NANCY OSTERBERG WOOD Submitted to the Office of Graduate and Professional Studies of Texas A&M University... in an online research tutorial. The four conditions comprised two levels of two factors: Media and Task. The two Media were Static, represented by a linked jpeg image of the artwork; and Dynamic Manipulation represented by an interactive Adobe Flash version...

  2. Autoclave nuclear criticality safety analysis

    SciTech Connect (OSTI)

    D`Aquila, D.M. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States); Tayloe, R.W. Jr. [Battelle, Columbus, OH (United States)

    1991-12-31

    Steam-heated autoclaves are used in gaseous diffusion uranium enrichment plants to heat large cylinders of UF{sub 6}. Nuclear criticality safety for these autoclaves is evaluated. To enhance criticality safety, systems are incorporated into the design of autoclaves to limit the amount of water present. These safety systems also increase the likelihood that any UF{sub 6} inadvertently released from a cylinder into an autoclave is not released to the environment. Up to 140 pounds of water can be held up in large autoclaves. This mass of water is sufficient to support a nuclear criticality when optimally combined with 125 pounds of UF{sub 6} enriched to 5 percent U{sup 235}. However, water in autoclaves is widely dispersed as condensed droplets and vapor, and is extremely unlikely to form a critical configuration with released UF{sub 6}.

  3. Lecture notes for criticality safety

    SciTech Connect (OSTI)

    Fullwood, R.

    1992-03-01

    These lecture notes for criticality safety are prepared for the training of Department of Energy supervisory, project management, and administrative staff. Technical training and basic mathematics are assumed. The notes are designed for a two-day course, taught by two lecturers. Video tapes may be used at the options of the instructors. The notes provide all the materials that are necessary but outside reading will assist in the fullest understanding. The course begins with a nuclear physics overview. The reader is led from the macroscopic world into the microscopic world of atoms and the elementary particles that constitute atoms. The particles, their masses and sizes and properties associated with radioactive decay and fission are introduced along with Einstein's mass-energy equivalence. Radioactive decay, nuclear reactions, radiation penetration, shielding and health-effects are discussed to understand protection in case of a criticality accident. Fission, the fission products, particles and energy released are presented to appreciate the dangers of criticality. Nuclear cross sections are introduced to understand the effectiveness of slow neutrons to produce fission. Chain reactors are presented as an economy; effective use of the neutrons from fission leads to more fission resulting in a power reactor or a criticality excursion. The six-factor formula is presented for managing the neutron budget. This leads to concepts of material and geometric buckling which are used in simple calculations to assure safety from criticality. Experimental measurements and computer code calculations of criticality are discussed. To emphasize the reality, historical criticality accidents are presented in a table with major ones discussed to provide lessons-learned. Finally, standards, NRC guides and regulations, and DOE orders relating to criticality protection are presented.

  4. Probalistic Criticality Consequence Evaluation (SCPB:N/A)

    SciTech Connect (OSTI)

    P. Gottlieb; J.W. Davis; J.R. Massari

    1996-09-04

    This analysis is prepared by the Mined Geologic Disposal System (MGDS) Waste Package Development (WPD) department with the objective of providing a comprehensive, conservative estimate of the consequences of the criticality which could possibly occur as the result of commercial spent nuclear fuel emplaced in the underground repository at Yucca Mountain. The consequences of criticality are measured principally in terms of the resulting changes in radionuclide inventory as a function of the power level and duration of the criticality. The purpose of this analysis is to extend the prior estimates of increased radionuclide inventory (Refs. 5.52 and 5.54), for both internal and external criticality. This analysis, and similar estimates and refinements to be completed before the end of fiscal year 1997, will be provided as input to Total System Performance Assessment-Viability Assessment (TSPA-VA) to demonstrate compliance with the repository performance objectives.

  5. Microsoft Word - Critical Infrastructure Security and Resilience...

    Broader source: Energy.gov (indexed) [DOE]

    White House Office of the Press Secretary For Immediate Release October 31, 2013 Presidential Proclamation -- Critical Infrastructure Security and Resilience Month, 2013 CRITICAL...

  6. DOE and Critical Materials Video (Text Version)

    Broader source: Energy.gov [DOE]

    This is a text version of the "DOE and Critical Materials" video presented at the Critical Materials Workshop, held on April 3, 2012 in Arlington, Virginia.

  7. Nuclear criticality safety: 2-day training course

    SciTech Connect (OSTI)

    Schlesser, J.A.

    1997-02-01

    This compilation of notes is presented as a source reference for the criticality safety course. At the completion of this training course, the attendee will: be able to define terms commonly used in nuclear criticality safety; be able to appreciate the fundamentals of nuclear criticality safety; be able to identify factors which affect nuclear criticality safety; be able to identify examples of criticality controls as used as Los Alamos; be able to identify examples of circumstances present during criticality accidents; have participated in conducting two critical experiments; be asked to complete a critique of the nuclear criticality safety training course.

  8. CRITICAL INFRASTRUCTURE PROTECTION Multiple Efforts to Secure...

    Office of Environmental Management (EM)

    CRITICAL INFRASTRUCTURE PROTECTION Multiple Efforts to Secure Control Systems Are Under Way, but Challenges Remain CRITICAL INFRASTRUCTURE PROTECTION Multiple Efforts to Secure...

  9. PRECLOSURE CRITICALITY ANALYSIS PROCESS REPORT

    SciTech Connect (OSTI)

    A.E. Danise

    2004-10-25

    This report describes a process for performing preclosure criticality analyses for a repository at Yucca Mountain, Nevada. These analyses will be performed from the time of receipt of fissile material until permanent closure of the repository (preclosure period). The process describes how criticality safety analyses will be performed for various configurations of waste in or out of waste packages that could occur during preclosure as a result of normal operations or event sequences. The criticality safety analysis considers those event sequences resulting in unanticipated moderation, loss of neutron absorber, geometric changes, or administrative errors in waste form placement (loading) of the waste package. The report proposes a criticality analyses process for preclosure to allow a consistent transition from preclosure to postclosure, thereby possibly reducing potential cost increases and delays in licensing of Yucca Mountain. The proposed approach provides the advantage of using a parallel regulatory framework for evaluation of preclosure and postclosure performance and is consistent with the U.S. Nuclear Regulatory Commission's approach of supporting risk-informed, performance-based regulation for fuel cycle facilities, ''Yucca Mountain Review Plan, Final Report'', and 10 CFR Part 63. The criticality-related criteria for ensuring subcriticality are also described as well as which guidance documents will be utilized. Preclosure operations and facilities have significant similarities to existing facilities and operations currently regulated by the U.S. Nuclear Regulatory Commission; therefore, the design approach for preclosure criticality safety will be dictated by existing regulatory requirements while using a risk-informed approach with burnup credit for in-package operations.

  10. Brand the Pricing: Critical Critique 

    E-Print Network [OSTI]

    Alam Kazmi, Syed Hasnain

    2015-01-01

    and huge retailer like, Walmart offers shelf labels for itsadvertising retailer (such as; Walmart) across product level

  11. Liouville Brownian motion at criticality

    E-Print Network [OSTI]

    Rémi Rhodes; Vincent Vargas

    2015-02-15

    In this paper, we construct the Brownian motion of Liouville Quantum Gravity with central charge $c=1$ (more precisely we restrict to the corresponding free field theory). Liouville quantum gravity with $c=1$ corresponds to two-dimensional string theory and is the conjectural scaling limit of large planar maps weighted with a $O(n=2)$ loop model or a $Q=4$-state Potts model embedded in a two dimensional surface in a conformal manner. Following \\cite{GRV1}, we start by constructing the critical LBM from one fixed point $x\\in\\mathbb{R}^2$ (or $x\\in\\S^2$), which amounts to changing the speed of a standard planar Brownian motion depending on the local behaviour of the critical Liouville measure $M'(dx)=-X(x)e^{2X(x)}\\,dx$ (where $X$ is a Gaussian Free Field, say on $\\mathbb{S}^2$). Extending this construction simultaneously to all points in $\\mathbb{R}^2$ requires a fine analysis of the potential properties of the measure $M'$. This allows us to construct a strong Markov process with continuous sample paths living on the support of $M'$, namely a dense set of Hausdorff dimension $0$. We finally construct the associated Liouville semigroup, resolvent, Green function, heat kernel and Dirichlet form. In passing, we extend to quite a general setting the construction of the critical Gaussian multiplicative chaos that was initiated in \\cite{Rnew7,Rnew12} and also establish new capacity estimates for the critical Gaussian multiplicative chaos.

  12. Managing Critical Management Improvement Initiatives

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2003-10-01

    Provides requirements and responsibilities for planning, executing and assessing critical management improvement initiatives within DOE. DOE N 251.59, dated 9/27/2004, extends this Notice until 10/01/2005. Archived 11-8-10. Does not cancel other directives.

  13. High critical current superconducting tapes

    DOE Patents [OSTI]

    Holesinger, Terry G. (Los Alamos, NM); Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2003-09-23

    Improvements in critical current capacity for superconducting film structures are disclosed and include the use of a superconducting RE-BCO layer including a mixture of rare earth metals, e.g., yttrium and europium, where the ratio of yttrium to europium in the RE-BCO layer ranges from about 3 to 1 to from about 1.5 to 1.

  14. First Responders and Criticality Accidents

    SciTech Connect (OSTI)

    Valerie L. Putman; Douglas M. Minnema

    2005-11-01

    Nuclear criticality accident descriptions typically include, but do not focus on, information useful to first responders. We studied these accidents, noting characteristics to help (1) first responders prepare for such an event and (2) emergency drill planners develop appropriate simulations for training. We also provide recommendations to help people prepare for such events in the future.

  15. Critical phenomena in atmospheric precipitation

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS Critical phenomena in atmospheric precipitation OLE PETERS1,2,3 * AND J. DAVID NEELIN3 1 convection and precipitation (the order parameter)--with correlated regions on scales of tens to hundreds the climatological mean by an order of magnitude or more. Moist convection and the accompanying precipitation have

  16. Los Alamos Critical Assemblies Facility

    SciTech Connect (OSTI)

    Malenfant, R.E.

    1981-06-01

    The Critical Assemblies Facility of the Los Alamos National Laboratory has been in existence for thirty-five years. In that period, many thousands of measurements have been made on assemblies of /sup 235/U, /sup 233/U, and /sup 239/Pu in various configurations, including the nitrate, sulfate, fluoride, carbide, and oxide chemical compositions and the solid, liquid, and gaseous states. The present complex of eleven operating machines is described, and typical applications are presented.

  17. Critical Infrastructure and Cyber Security 

    E-Print Network [OSTI]

    Doll, Abby; Pirrong, Renee; Jennings, Matthew; Stasny, George; Giblin, Andy; Shaffer, Steph; Anderson, Aimee

    2011-01-01

    cyber security. They designated responsibility for cyber-security to the newly formed Department of Homeland Security, a duty that has continued to today 3. The group was tasked with creating a method of protecting the critical components.... 2010. 15 Mar. 2011. http://www.d tic.mil/doctrine/new_pubs/jp1_02.pdf 10 Comments on the Economic and Security Implications Of Recent Developments in the World Oil Market , 107th Cong. (2000) (testimony of Robert E. Ebel). http...

  18. A Desktop 3D Printer in Safety-Critical Java Trur Biskopst Strm

    E-Print Network [OSTI]

    Schoeberl, Martin

    A Desktop 3D Printer in Safety-Critical Java Tórur Biskopstø Strøm Department of Informatics according to the specification. In this paper we present a 3D printer and its safety-critical Java level 1 evaluate the specification by implementing a RepRap 3D desktop printer as a use case. A RepRap is a desktop

  19. Action and Inaction Levels in Pest Management. 

    E-Print Network [OSTI]

    Sterling, Winfield

    1984-01-01

    to this problem be to use the term "action level" as a replacement term "economic threshold" and the term "inac level" for the critical natural enemy densities (134). terms are more fitting because economic and factors are both important in pest manage dec... component of level model. If the plant has reserves of n sufficient time remaining during the growing replace damaged fruit , then a higher action level be set. The effect of leaf damage as related phenological stage of cotton plant growth is ill...

  20. Method for critical software event execution reliability in high integrity software

    SciTech Connect (OSTI)

    Kidd, M.E. [Sandia National Labs., Albuquerque, NM (United States)

    1997-11-01

    This report contains viewgraphs on a method called SEER, which provides a high level of confidence that critical software driven event execution sequences faithfully exceute in the face of transient computer architecture failures in both normal and abnormal operating environments.

  1. Method for destroying halocarbon compositions using a critical solvent

    DOE Patents [OSTI]

    Ginosar, Daniel M.; Fox, Robert V.; Janikowski, Stuart K.

    2006-01-10

    A method for destroying halocarbons. Halocarbon materials are reacted in a dehalogenation process wherein they are combined with a solvent in the presence of a catalyst. A hydrogen-containing solvent is preferred which functions as both a solvating agent and hydrogen donor. To augment the hydrogen donation capacity of the solvent if needed (or when non-hydrogen-containing solvents are used), a supplemental hydrogen donor composition may be employed. In operation, at least one of the temperature and pressure of the solvent is maintained near, at, or above a critical level. For example, the solvent may be in (1) a supercritical state; (2) a state where one of the temperature or pressure thereof is at or above critical; or (3) a state where at least one of the temperature and pressure thereof is near-critical. This system provides numerous benefits including improved reaction rates, efficiency, and versatility.

  2. Solution High-Energy Burst Assembly (SHEBA) results from subprompt critical experiments with uranyl fluoride fuel

    SciTech Connect (OSTI)

    Cappiello, C.C.; Butterfield, K.B.; Sanchez, R.G.; Bounds, J.A.; Kimpland, R.H.; Damjanovich, R.P.; Jaegers, P.J.

    1997-08-01

    Experiments were performed to measure a variety of parameters for SHEBA: behavior of the facility during transient and steady-state operation; characteristics of the SHEBA fuel; delayed-critical solution height vs solution temperature; initial reactor period and reactivity vs solution height; calibration of power level vs reactor power instrumentation readings; flux profile in SHEBA; radiation levels and neutron spectra outside the assembly for code verification and criticality alarm and dosimetry purposes; and effect on reactivity of voids in the fuel.

  3. Motives for Practicing Criticism as a ‘Rational Science’ in Lord Kames’s Elements of Criticism

    E-Print Network [OSTI]

    Innocenti, Beth

    2001-01-01

    The way Lord Kames practices criticism in Elements of Criticism (1762) is not motivated by the new philosophy per se. His use of the new philosophy in the practice of criticism addresses social, political, and nationalistic circumstances. After...

  4. Only critical information was scanned

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouthReport for the Weldon Spring,7=cr5rnP 7694 i+lJNewS e Only critical

  5. Influence of Rotations on the Critical State of Soil Mechanics

    E-Print Network [OSTI]

    W. F. Oquendo; J. D. Muñoz; A. Lizcano

    2010-11-23

    The ability of grains to rotate can play a crucial role on the collective behavior of granular media. It has been observed in computer simulations that imposing a torque at the contacts modifies the force chains, making support chains less important. In this work we investigate the effect of a gradual hindering of the grains rotations on the so-called critical state of soil mechanics. The critical state is an asymptotic state independent of the initial solid fraction where deformations occur at a constant shear strength and compactness. We quantify the difficulty to rotate by a friction coefficient at the level of particles, acting like a threshold. We explore the effect of this particle-level friction coefficient on the critical state by means of molecular dynamics simulations of a simple shear test on a poly-disperse sphere packing. We found that the larger the difficulty to rotate, the larger the final shear strength of the sample. Other micro-mechanical variables, like the structural anisotropy and the distribution of forces, are also influenced by the threshold. These results reveal the key role of rotations on the critical behavior of soils and suggest the inclusion of rotational variables into their constitutive equations.

  6. Critical Materials Workshop Plenary Session Videos

    Broader source: Energy.gov [DOE]

    Above are the plenary session videos of the Critical Materials Workshop held on April 3, 2012 in Arlington, Virginia.

  7. Guide to Critical Infrastructure Protection Cyber Vulnerability...

    Broader source: Energy.gov (indexed) [DOE]

    Infrastructure Protection Cyber Vulnerability Assessment More Documents & Publications Wireless System Considerations When Implementing NERC Critical Infrastructure Protection...

  8. Critical Materials Workshop Final Participant List

    Office of Energy Efficiency and Renewable Energy (EERE)

    List of participants who attended the Critical Materials Workshop held on April 3, 2012 in Arlington, VA

  9. Fusion algebra of critical percolation

    E-Print Network [OSTI]

    Jorgen Rasmussen; Paul A. Pearce

    2007-08-08

    We present an explicit conjecture for the chiral fusion algebra of critical percolation considering Virasoro representations with no enlarged or extended symmetry algebra. The representations we take to generate fusion are countably infinite in number. The ensuing fusion rules are quasi-rational in the sense that the fusion of a finite number of these representations decomposes into a finite direct sum of these representations. The fusion rules are commutative, associative and exhibit an sl(2) structure. They involve representations which we call Kac representations of which some are reducible yet indecomposable representations of rank 1. In particular, the identity of the fusion algebra is a reducible yet indecomposable Kac representation of rank 1. We make detailed comparisons of our fusion rules with the recent results of Eberle-Flohr and Read-Saleur. Notably, in agreement with Eberle-Flohr, we find the appearance of indecomposable representations of rank 3. Our fusion rules are supported by extensive numerical studies of an integrable lattice model of critical percolation. Details of our lattice findings and numerical results will be presented elsewhere.

  10. Criticality safety basics, a study guide

    SciTech Connect (OSTI)

    V. L. Putman

    1999-09-01

    This document is a self-study and classroom guide, for criticality safety of activities with fissile materials outside nuclear reactors. This guide provides a basic overview of criticality safety and criticality accident prevention methods divided into three parts: theory, application, and history. Except for topic emphasis, theory and history information is general, while application information is specific to the Idaho National Engineering and Environmental Laboratory (INEEL). Information presented here should be useful to personnel who must know criticality safety basics to perform their assignments safely or to design critically safe equipment or operations. However, the guide's primary target audience is fissile material handler candidates.

  11. Taiwan industrial cooperation program technology transfer for low-level radioactive waste final disposal - phase I.

    SciTech Connect (OSTI)

    Knowlton, Robert G.; Cochran, John Russell; Arnold, Bill Walter; Jow, Hong-Nian; Mattie, Patrick D.; Schelling, Frank Joseph Jr.

    2007-01-01

    Sandia National Laboratories and the Institute of Nuclear Energy Research, Taiwan have collaborated in a technology transfer program related to low-level radioactive waste (LLW) disposal in Taiwan. Phase I of this program included regulatory analysis of LLW final disposal, development of LLW disposal performance assessment capabilities, and preliminary performance assessments of two potential disposal sites. Performance objectives were based on regulations in Taiwan and comparisons to those in the United States. Probabilistic performance assessment models were constructed based on limited site data using software including GoldSim, BLT-MS, FEHM, and HELP. These software codes provided the probabilistic framework, container degradation, waste-form leaching, groundwater flow, radionuclide transport, and cover infiltration simulation capabilities in the performance assessment. Preliminary performance assessment analyses were conducted for a near-surface disposal system and a mined cavern disposal system at two representative sites in Taiwan. Results of example calculations indicate peak simulated concentrations to a receptor within a few hundred years of LLW disposal, primarily from highly soluble, non-sorbing radionuclides.

  12. Critical heat flux test apparatus

    DOE Patents [OSTI]

    Welsh, Robert E. (West Mifflin, PA); Doman, Marvin J. (McKeesport, PA); Wilson, Edward C. (West Mifflin, PA)

    1992-01-01

    An apparatus for testing, in situ, highly irradiated specimens at high temperature transients is provided. A specimen, which has a thermocouple device attached thereto, is manipulated into test position in a sealed quartz heating tube by a robot. An induction coil around a heating portion of the tube is powered by a radio frequency generator to heat the specimen. Sensors are connected to monitor the temperatures of the specimen and the induction coil. A quench chamber is located below the heating portion to permit rapid cooling of the specimen which is moved into this quench chamber once it is heated to a critical temperature. A vacuum pump is connected to the apparatus to collect any released fission gases which are analyzed at a remote location.

  13. 2011 Annual Criticality Safety Program Performance Summary

    SciTech Connect (OSTI)

    Andrea Hoffman

    2011-12-01

    The 2011 review of the INL Criticality Safety Program has determined that the program is robust and effective. The review was prepared for, and fulfills Contract Data Requirements List (CDRL) item H.20, 'Annual Criticality Safety Program performance summary that includes the status of assessments, issues, corrective actions, infractions, requirements management, training, and programmatic support.' This performance summary addresses the status of these important elements of the INL Criticality Safety Program. Assessments - Assessments in 2011 were planned and scheduled. The scheduled assessments included a Criticality Safety Program Effectiveness Review, Criticality Control Area Inspections, a Protection of Controlled Unclassified Information Inspection, an Assessment of Criticality Safety SQA, and this management assessment of the Criticality Safety Program. All of the assessments were completed with the exception of the 'Effectiveness Review' for SSPSF, which was delayed due to emerging work. Although minor issues were identified in the assessments, no issues or combination of issues indicated that the INL Criticality Safety Program was ineffective. The identification of issues demonstrates the importance of an assessment program to the overall health and effectiveness of the INL Criticality Safety Program. Issues and Corrective Actions - There are relatively few criticality safety related issues in the Laboratory ICAMS system. Most were identified by Criticality Safety Program assessments. No issues indicate ineffectiveness in the INL Criticality Safety Program. All of the issues are being worked and there are no imminent criticality concerns. Infractions - There was one criticality safety related violation in 2011. On January 18, 2011, it was discovered that a fuel plate bundle in the Nuclear Materials Inspection and Storage (NMIS) facility exceeded the fissionable mass limit, resulting in a technical safety requirement (TSR) violation. The TSR limits fuel plate bundles to 1085 grams U-235, which is the maximum loading of an ATR fuel element. The overloaded fuel plate bundle contained 1097 grams U-235 and was assembled under an 1100 gram U-235 limit in 1982. In 2003, the limit was reduced to 1085 grams citing a new criticality safety evaluation for ATR fuel elements. The fuel plate bundle inventories were not checked for compliance prior to implementing the reduced limit. A subsequent review of the NMIS inventory did not identify further violations. Requirements Management - The INL Criticality Safety program is organized and well documented. The source requirements for the INL Criticality Safety Program are from 10 CFR 830.204, DOE Order 420.1B, Chapter III, 'Nuclear Criticality Safety,' ANSI/ANS 8-series Industry Standards, and DOE Standards. These source requirements are documented in LRD-18001, 'INL Criticality Safety Program Requirements Manual.' The majority of the criticality safety source requirements are contained in DOE Order 420.1B because it invokes all of the ANSI/ANS 8-Series Standards. DOE Order 420.1B also invokes several DOE Standards, including DOE-STD-3007, 'Guidelines for Preparing Criticality Safety Evaluations at Department of Energy Non-Reactor Nuclear Facilities.' DOE Order 420.1B contains requirements for DOE 'Heads of Field Elements' to approve the criticality safety program and specific elements of the program, namely, the qualification of criticality staff and the method for preparing criticality safety evaluations. This was accomplished by the approval of SAR-400, 'INL Standardized Nuclear Safety Basis Manual,' Chapter 6, 'Prevention of Inadvertent Criticality.' Chapter 6 of SAR-400 contains sufficient detail and/or reference to the specific DOE and contractor documents that adequately describe the INL Criticality Safety Program per the elements specified in DOE Order 420.1B. The Safety Evaluation Report for SAR-400 specifically recognizes that the approval of SAR-400 approves the INL Criticality Safety Program. No new source requirements were released in 2011. A revision to LRD-18001 is

  14. American Institute of Aeronautics and Astronautics Automation Bias in Intelligent Time Critical Decision

    E-Print Network [OSTI]

    Cummings, Mary "Missy"

    American Institute of Aeronautics and Astronautics 1 Automation Bias in Intelligent Time Critical levels of automation can be introduced by intelligent decision support systems, from fully automated, where the operator is completely left out of the decision process, to minimal levels of automation

  15. Influence of Rotations on the Critical State of Soil Mechanics

    E-Print Network [OSTI]

    Oquendo, W F; Lizcano, A

    2010-01-01

    The ability of grains to rotate can play a crucial role on the collective behavior of granular media. It has been observed in computer simulations that imposing a torque at the contacts modifies the force chains, making support chains less important. In this work we investigate the effect of a gradual hindering of the grains rotations on the so-called critical state of soil mechanics. The critical state is an asymptotic state independent of the initial solid fraction where deformations occur at a constant shear strength and compactness. We quantify the difficulty to rotate by a friction coefficient at the level of particles, acting like a threshold. We explore the effect of this particle-level friction coefficient on the critical state by means of molecular dynamics simulations of a simple shear test on a poly-disperse sphere packing. We found that the larger the difficulty to rotate, the larger the final shear strength of the sample. Other micro-mechanical variables, like the structural anisotropy and the di...

  16. NQA-1 Commercial Grade Dedication Critical Characteristics |...

    Office of Environmental Management (EM)

    Dedication Critical Characteristics May 5, 2015 Presenter: Randy P. Lanham, PE, CSP, Fire Protection Chief Engineer Consolidated Nuclear Solutions - Pantex, LLC Topics Covered:...

  17. Computing Criticality of Lines in Power Systems

    SciTech Connect (OSTI)

    Pinar, Ali; Reichert, Adam; Lesieutre, Bernard

    2006-10-13

    We propose a computationally efficient method based onnonlinear optimization to identify critical lines, failure of which cancause severe blackouts. Our method computes criticality measure for alllines at a time, as opposed to detecting a single vulnerability,providing a global view of the system. This information on criticality oflines can be used to identify multiple contingencies by selectivelyexploring multiple combinations of broken lines. The effectiveness of ourmethod is demonstrated on the IEEE 30 and 118 bus systems, where we canvery quickly detect the most critical lines in the system and identifysevere multiple contingencies.

  18. SILENE Benchmark Critical Experiments for Criticality Accident Alarm Systems

    SciTech Connect (OSTI)

    Miller, Thomas Martin; Reynolds, Kevin H.

    2011-01-01

    In October 2010 a series of benchmark experiments was conducted at the Commissariat a Energie Atomique et aux Energies Alternatives (CEA) Valduc SILENE [1] facility. These experiments were a joint effort between the US Department of Energy (DOE) and the French CEA. The purpose of these experiments was to create three benchmarks for the verification and validation of radiation transport codes and evaluated nuclear data used in the analysis of criticality accident alarm systems (CAASs). This presentation will discuss the geometric configuration of these experiments and the quantities that were measured and will present some preliminary comparisons between the measured data and calculations. This series consisted of three single-pulsed experiments with the SILENE reactor. During the first experiment the reactor was bare (unshielded), but during the second and third experiments it was shielded by lead and polyethylene, respectively. During each experiment several neutron activation foils and thermoluminescent dosimeters (TLDs) were placed around the reactor, and some of these detectors were themselves shielded from the reactor by high-density magnetite and barite concrete, standard concrete, and/or BoroBond. All the concrete was provided by CEA Saclay, and the BoroBond was provided by Y-12 National Security Complex. Figure 1 is a picture of the SILENE reactor cell configured for pulse 1. Also included in these experiments were measurements of the neutron and photon spectra with two BICRON BC-501A liquid scintillators. These two detectors were provided and operated by CEA Valduc. They were set up just outside the SILENE reactor cell with additional lead shielding to prevent the detectors from being saturated. The final detectors involved in the experiments were two different types of CAAS detectors. The Babcock International Group provided three CIDAS CAAS detectors, which measured photon dose and dose rate with a Geiger-Mueller tube. CIDAS detectors are currently in use at Y-12 in the newly constructed Highly Enriched Uranium Materials Facility. The second CAAS detector used a {sup 6}LiF TLD to absorb neutrons and a silicon detector to count the charge particles released by these absorption events. Lawrence Livermore National Laboratory provided four of these detectors, which had formerly been used at the Rocky Flats facility in the United States.

  19. Working Gas Capacity of Salt Caverns

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan3Additions (Million2.8 2.6 2.7 2.7 2.9 3.0 1993-201496,092271,785

  20. Natural Gas Salt Caverns Storage Capacity

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb Marthrough 1996) in155 13,348 47,873 8,091

  1. Gaines Cavern Wind Project | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoopButtePowerEdistoWhiskeyFootprintGEXA Corp. (Delaware) JumpGadir Solar

  2. Component-Level Demonstration of a Microfabricated Atomic Frequency Reference

    E-Print Network [OSTI]

    Popovic, Zoya

    size and lower power dissipation. In particular, atomic clocks based on coherent population trappingComponent-Level Demonstration of a Microfabricated Atomic Frequency Reference V. Gerginov, S component-level functionality of the three critical subsystems for a miniature atomic clock based

  3. Optimal recovery sequencing for critical infrastructure resilience assessment.

    SciTech Connect (OSTI)

    Vugrin, Eric D.; Brown, Nathanael J. K.; Turnquist, Mark Alan

    2010-09-01

    Critical infrastructure resilience has become a national priority for the U. S. Department of Homeland Security. System resilience has been studied for several decades in many different disciplines, but no standards or unifying methods exist for critical infrastructure resilience analysis. This report documents the results of a late-start Laboratory Directed Research and Development (LDRD) project that investigated the identification of optimal recovery strategies that maximize resilience. To this goal, we formulate a bi-level optimization problem for infrastructure network models. In the 'inner' problem, we solve for network flows, and we use the 'outer' problem to identify the optimal recovery modes and sequences. We draw from the literature of multi-mode project scheduling problems to create an effective solution strategy for the resilience optimization model. We demonstrate the application of this approach to a set of network models, including a national railroad model and a supply chain for Army munitions production.

  4. Abrasion Testing of Critical Components of Hydrokinetic Devices

    SciTech Connect (OSTI)

    Worthington, Monty; Ali, Muhammad; Ravens, Tom

    2013-12-06

    The objective of the Abrasion Testing of Critical Components of Hydrokinetic Devices (Project) was to test critical components of hydrokinetic devices in waters with high levels of suspended sediment – information that is widely applicable to the hydrokinetic industry. Tidal and river sites in Alaska typically have high suspended sediment concentrations. High suspended sediment also occurs in major rivers and estuaries throughout the world and throughout high latitude locations where glacial inputs introduce silt into water bodies. In assessing the vulnerability of technology components to sediment induced abrasion, one of the greatest concerns is the impact that the sediment may have on device components such as bearings and seals, failures of which could lead to both efficiency loss and catastrophic system failures.

  5. Italy in the Mediterranean Today: A New Critical Topography

    E-Print Network [OSTI]

    Fogu, Claudio; Re, Lucia

    2010-01-01

    Today: A New Critical Topography Claudio Fogu and Lucia Reto function as an ideal topography of the critical territory

  6. Critical technologies research: Opportunities for DOE

    SciTech Connect (OSTI)

    Not Available

    1992-12-01

    Recent studies have identified a number of critical technologies that are essential to the nation's defense, economic competitiveness, energy independence, and betterment of public health. The National Critical Technologies Panel (NCTP) has identified the following critical technology areas: Aeronautics and Surface Transportation; Biotechnology and Life Sciences; Energy and Environment; Information and Communications; Manufacturing; and Materials. Sponsored by the Department of Energy's Office of Energy Research (OER), the Critical Technologies Research Workshop was held in May 1992. Approximately 100 scientists, engineers, and managers from the national laboratories, industry, academia, and govemment participated. The objective of the Berkeley Workshop was to advance the role of the DOE multiprogram energy laboratories in critical technologies research by describing, defining, and illustrating research areas, opportunities, resources, and key decisions necessary to achieve national research goals. An agenda was developed that looked at DOE's capabilities and options for research in critical technologies and provided a forum for industry, academia, govemment, and the national laboratories to address: Critical technology research needs; existing research activities and resources; capabilities of the national laboratories; and opportunities for national laboratories, industries, and universities. The Workshop included plenary sessions in which presentations by technology and policy leaders set the context for further inquiry into critical technology issues and research opportunities. Separate sessions then focused on each of the following major areas of technology: Advanced materials; biotechnology and life sciences; energy and environment; information and communication; and manufacturing and transportation.

  7. Critical technologies research: Opportunities for DOE

    SciTech Connect (OSTI)

    Not Available

    1992-12-01

    Recent studies have identified a number of critical technologies that are essential to the nation`s defense, economic competitiveness, energy independence, and betterment of public health. The National Critical Technologies Panel (NCTP) has identified the following critical technology areas: Aeronautics and Surface Transportation; Biotechnology and Life Sciences; Energy and Environment; Information and Communications; Manufacturing; and Materials. Sponsored by the Department of Energy`s Office of Energy Research (OER), the Critical Technologies Research Workshop was held in May 1992. Approximately 100 scientists, engineers, and managers from the national laboratories, industry, academia, and govemment participated. The objective of the Berkeley Workshop was to advance the role of the DOE multiprogram energy laboratories in critical technologies research by describing, defining, and illustrating research areas, opportunities, resources, and key decisions necessary to achieve national research goals. An agenda was developed that looked at DOE`s capabilities and options for research in critical technologies and provided a forum for industry, academia, govemment, and the national laboratories to address: Critical technology research needs; existing research activities and resources; capabilities of the national laboratories; and opportunities for national laboratories, industries, and universities. The Workshop included plenary sessions in which presentations by technology and policy leaders set the context for further inquiry into critical technology issues and research opportunities. Separate sessions then focused on each of the following major areas of technology: Advanced materials; biotechnology and life sciences; energy and environment; information and communication; and manufacturing and transportation.

  8. Critical National Infrastructure Reliability Modeling and Analysis

    E-Print Network [OSTI]

    . · Telecommunications: Congestion or disruption of key communications nodes by fire, wind, water, or sabotage · Power of Homeland Security is protection of our critical national infrastructures including power, communications, transportation, and water. This paper presents models to quantify the interdependencies of critical

  9. Steady water waves with multiple critical layers

    E-Print Network [OSTI]

    Mats Ehrnström; Joachim Escher; Erik Wahlén

    2011-04-01

    We construct small-amplitude periodic water waves with multiple critical layers. In addition to waves with arbitrarily many critical layers and a single crest in each period, two-dimensional sets of waves with several crests and troughs in each period are found. The setting is that of steady two-dimensional finite-depth gravity water waves with vorticity.

  10. Self-organizing criticality among Chinese cities 

    E-Print Network [OSTI]

    Li, Shujuan

    2010-07-14

    This dissertation employs the theory of self-organizing criticality (SOC) into the study of Chinese cities. SOC was proposed at the end of the 1980s to explain system complexity by combining both self-organizing and critical behaviors. SOC has been...

  11. Critical aspects of hierarchical protein folding

    E-Print Network [OSTI]

    Alex Hansen; Mogens H. Jensen; Kim Sneppen; Giovanni Zocchi

    1998-01-13

    We argue that the first order folding transitions of proteins observed at physiological chemical conditions end in a critical point for a given temperature and chemical potential of the surrounding water. We investigate this critical point using a hierarchical Hamiltonian and determine its universality class. This class differs qualitatively from those of other known models.

  12. Enhancing critical current density of cuprate superconductors

    DOE Patents [OSTI]

    Chaudhari, Praveen

    2015-06-16

    The present invention concerns the enhancement of critical current densities in cuprate superconductors. Such enhancement of critical current densities include using wave function symmetry and restricting movement of Abrikosov (A) vortices, Josephson (J) vortices, or Abrikosov-Josephson (A-J) vortices by using the half integer vortices associated with d-wave symmetry present in the grain boundary.

  13. COMPUTER-BASED CRITICS Gerhard Fischer

    E-Print Network [OSTI]

    Fischer, Gerhard

    than I , we are bUilding systems that augment human intelligence -- in other words, we are building], active and passive help systems [12], design environments [11], and critics [7, 13], which we focus- building experience. We propose a general framework for critics, present specific requirements

  14. Incoherent transport in clean quantum critical metals

    E-Print Network [OSTI]

    Richard A. Davison; Blaise Goutéraux; Sean A. Hartnoll

    2015-07-25

    In a clean quantum critical metal, and in the absence of umklapp, most d.c. conductivities are formally infinite due to momentum conservation. However, there is a particular combination of the charge and heat currents which has a finite, universal conductivity. In this paper, we describe the physics of this conductivity $\\sigma_Q$ in quantum critical metals obtained by charge doping a strongly interacting conformal field theory. We show that it satisfies an Einstein relation and controls the diffusivity of a conserved charge in the metal. We compute $\\sigma_Q$ in a class of theories with holographic gravitational duals. Finally, we show how the temperature scaling of $\\sigma_Q$ depends on certain critical exponents characterizing the quantum critical metal. The holographic results are found to be reproduced by the scaling analysis, with the charge density operator becoming marginal in the emergent low energy quantum critical theory.

  15. Incoherent transport in clean quantum critical metals

    E-Print Network [OSTI]

    Davison, Richard A; Hartnoll, Sean A

    2015-01-01

    In a clean quantum critical metal, and in the absence of umklapp, most d.c. conductivities are formally infinite due to momentum conservation. However, there is a particular combination of the charge and heat currents which has a finite, universal conductivity. In this paper, we describe the physics of this conductivity $\\sigma_Q$ in quantum critical metals obtained by charge doping a strongly interacting conformal field theory. We show that it satisfies an Einstein relation and controls the diffusivity of a conserved charge in the metal. We compute $\\sigma_Q$ in a class of theories with holographic gravitational duals. Finally, we show how the temperature scaling of $\\sigma_Q$ depends on certain critical exponents characterizing the quantum critical metal. The holographic results are found to be reproduced by the scaling analysis, with the charge density operator becoming marginal in the emergent low energy quantum critical theory.

  16. Criticality Code Validation Exercises with TSUNAMI

    SciTech Connect (OSTI)

    Rearden, Bradley T [ORNL

    2007-01-01

    In the criticality code validation of common systems, many paths may exist to a correct bias, bias uncertainty, and upper subcritical limit. The challenge for the criticality analyst is to select an efficient, defensible, and safe methodology to consistently obtain the correct values. One method of testing criticality code validation techniques is to use a sample system with a known bias as a test application and determine whether the methods employed can reproduce the known bias. In this paper, a low-enriched uranium (LEU) lattice critical experiment with a known bias is used as the test application, and numerous other LEU experiments are used as the benchmarks for the criticality code validation exercises using traditional and advanced parametric techniques. The parameters explored are enrichment, energy of average lethargy causing fission (EALF), and the TSUNAMI integral index ck with experiments with varying degrees of similarity. This paper is an extension of a previously published summary.

  17. Analysis of criticality alarm system response to an accidental criticality outside the cascade process buildings at the Portsmouth Gaseous Diffusion Plant

    SciTech Connect (OSTI)

    Negron, S.B.; Tayloe, R.W. Jr.; Dobelbower, M.C. [Battelle, Columbus, OH (United States)

    1994-07-01

    Neutron dose rates at detector positions within the X-326, X-330, and X-333 buildings were evaluated for an accidental criticality outside of each building. As fissile material bearing equipment and containers are moved to and from each building, the possibility exists for a criticality accident to occur. This analysis demonstrates that a criticality accident which occurs at any position on the access roads alongside a process building can be detected. The detectable area includes all points within the access road boundary along each face of each building. This analysis also demonstrates that the criticality alarm systems of the process buildings will respond to criticality events occurring within the tie lines connecting the process buildings. This analysis was performed using the MCNP Monte Carlo neutron-proton transport code. The radiation source is the neutron leakage spectrum of a critical solution of 4.95 percent enriched UO{sub 2}F{sub 2}-H{sub 2}O at a power level corresponding to the ANSI ANS 8.3. Standard minimum accident of concern. The evaluated neutron fluxes were converted to neutron dose rates by use of the Henderson free-in-air response functions. Critical source positions correspond to the farthest source to detector distances on the access roads along each face of the three buildings, and the centerpoint of the building tie lines. This report contains the methodology used for this study, a background on the data used, and a section about the assumptions and limits to all conclusions.

  18. Critical Mathematics Pedagogy: Transforming Teachers' Practices David W. Stinson, Ph.D., Assistant Professor-Mathematics Education

    E-Print Network [OSTI]

    Spagnolo, Filippo

    Critical Mathematics Pedagogy: Transforming Teachers' Practices David W. Stinson, Ph.D., Assistant Professor-Mathematics Education with Carla R. Bidwell, Christopher C. Jett, Ginny C. Powell, Mary M. Thurman of a graduate-level mathematics education course that focused on critical theory and teaching for social justice

  19. Investigation of downward facing critical heat flux with water-based nanofluids for In-Vessel Retention applications

    E-Print Network [OSTI]

    DeWitt, Gregory L

    2011-01-01

    In-Vessel Retention ("IVR") is a severe accident management strategy that is power limiting to the Westinghouse AP1000 due to critical heat flux ("CHF") at the outer surface of the reactor vessel. Increasing the CHF level ...

  20. Seminar in Critical Inquiry Twenty-first Century Nuclear Systems

    SciTech Connect (OSTI)

    LeMone, D. V.

    2002-02-25

    Critical Inquiry, has not only been successful in increasing university student retention rate but also in improving student academic performance beyond the initial year of transition into the University. The seminar course herein reviewed is a balanced combination of student personal and academic skill development combined with a solid background in modern nuclear systems. It is a valid premise to assume that entering students as well as stakeholders of the general public demonstrate equal levels of capability. Nuclear systems is designed to give a broad and basic knowledge of nuclear power, medical, industrial, research, and military systems (nuclear systems) in 20-25 hours.

  1. The Enterprise Level Roadmap

    E-Print Network [OSTI]

    Lean Advancement Initiative

    2000-01-01

    The Enterprise Level Roadmap is part of a Transition-To-Lean Guide, a three volume set of materials designed to help a user navigate through the Roadmap at increasingly deeper levels of detail.

  2. Nuclear Criticality Safety Guide for Fire Protection

    Office of Energy Efficiency and Renewable Energy (EERE)

    This guide is intended to provide information for use by fire protection professionals in the application of reasonable methods of fire protection in those facilities where there is a potential for nuclear criticality.

  3. Critical-Point Structure in Finite Nuclei

    E-Print Network [OSTI]

    A. Leviatan

    2006-12-04

    Properties of quantum shape-phase transitions in finite nuclei are considered in the framework of the interacting boson model. Special emphasis is paid to the dynamics at the critical-point of a general first-order phase transition.

  4. Neutron absorbing coating for nuclear criticality control

    DOE Patents [OSTI]

    Mizia, Ronald E. (Idaho Falls, ID); Wright, Richard N. (Idaho Falls, ID); Swank, William D. (Idaho Falls, ID); Lister, Tedd E. (Idaho Falls, ID); Pinhero, Patrick J. (Idaho Falls, ID)

    2007-10-23

    A neutron absorbing coating for use on a substrate, and which provides nuclear criticality control is described and which includes a nickel, chromium, molybdenum, and gadolinium alloy having less than about 5% boron, by weight.

  5. Intervention: Critical physical geography Rebecca Lave

    E-Print Network [OSTI]

    Lave, Rebecca

    Intervention: Critical physical geography Rebecca Lave Department of Geography, Indiana University Matthew W. Wilson Department of Geography, University of Kentucky Elizabeth S. Barron Department Christine Biermann Department of Geography, The Ohio State University Mark A. Carey Department of History

  6. Iterative Methods for Criticality Computations in Neutron

    E-Print Network [OSTI]

    Scheichl, Robert

    reactor (i.e. the criticality of the reactor), and thus plays an important role in the design and safety provides rather precise criteria on how accurate the inner solves need to be in order for the whole

  7. CRITICALITY SAFETY CONTROLS AND THE SAFETY BASIS AT PFP

    SciTech Connect (OSTI)

    Kessler, S

    2009-04-21

    With the implementation of DOE Order 420.1B, Facility Safety, and DOE-STD-3007-2007, 'Guidelines for Preparing Criticality Safety Evaluations at Department of Energy Non-Reactor Nuclear Facilities', a new requirement was imposed that all criticality safety controls be evaluated for inclusion in the facility Documented Safety Analysis (DSA) and that the evaluation process be documented in the site Criticality Safety Program Description Document (CSPDD). At the Hanford site in Washington State the CSPDD, HNF-31695, 'General Description of the FH Criticality Safety Program', requires each facility develop a linking document called a Criticality Control Review (CCR) to document performance of these evaluations. Chapter 5, Appendix 5B of HNF-7098, Criticality Safety Program, provided an example of a format for a CCR that could be used in lieu of each facility developing its own CCR. Since the Plutonium Finishing Plant (PFP) is presently undergoing Deactivation and Decommissioning (D&D), new procedures are being developed for cleanout of equipment and systems that have not been operated in years. Existing Criticality Safety Evaluations (CSE) are revised, or new ones written, to develop the controls required to support D&D activities. Other Hanford facilities, including PFP, had difficulty using the basic CCR out of HNF-7098 when first implemented. Interpretation of the new guidelines indicated that many of the controls needed to be elevated to TSR level controls. Criterion 2 of the standard, requiring that the consequence of a criticality be examined for establishing the classification of a control, was not addressed. Upon in-depth review by PFP Criticality Safety staff, it was not clear that the programmatic interpretation of criterion 8C could be applied at PFP. Therefore, the PFP Criticality Safety staff decided to write their own CCR. The PFP CCR provides additional guidance for the evaluation team to use by clarifying the evaluation criteria in DOE-STD-3007-2007. In reviewing documents used in classifying controls for Nuclear Safety, it was noted that DOE-HDBK-1188, 'Glossary of Environment, Health, and Safety Terms', defines an Administrative Control (AC) in terms that are different than typically used in Criticality Safety. As part of this CCR, a new term, Criticality Administrative Control (CAC) was defined to clarify the difference between an AC used for criticality safety and an AC used for nuclear safety. In Nuclear Safety terms, an AC is a provision relating to organization and management, procedures, recordkeeping, assessment, and reporting necessary to ensure safe operation of a facility. A CAC was defined as an administrative control derived in a criticality safety analysis that is implemented to ensure double contingency. According to criterion 2 of Section IV, 'Linkage to the Documented Safety Analysis', of DOESTD-3007-2007, the consequence of a criticality should be examined for the purposes of classifying the significance of a control or component. HNF-PRO-700, 'Safety Basis Development', provides control selection criteria based on consequence and risk that may be used in the development of a Criticality Safety Evaluation (CSE) to establish the classification of a component as a design feature, as safety class or safety significant, i.e., an Engineered Safety Feature (ESF), or as equipment important to safety; or merely provides defense-in-depth. Similar logic is applied to the CACs. Criterion 8C of DOE-STD-3007-2007, as written, added to the confusion of using the basic CCR from HNF-7098. The PFP CCR attempts to clarify this criterion by revising it to say 'Programmatic commitments or general references to control philosophy (e.g., mass control or spacing control or concentration control as an overall control strategy for the process without specific quantification of individual limits) is included in the PFP DSA'. Table 1 shows the PFP methodology for evaluating CACs. This evaluation process has been in use since February of 2008 and has proven to be simple and effective. Each control identified i

  8. Liquid level detector

    DOE Patents [OSTI]

    Grasso, A.P.

    1984-02-21

    A liquid level detector for low pressure boilers. A boiler tank, from which vapor, such as steam, normally exits via a main vent, is provided with a vertical side tube connected to the tank at the desired low liquid level. When the liquid level falls to the level of the side tube vapor escapes therethrough causing heating of a temperature sensitive device located in the side tube, which, for example, may activate a liquid supply means for adding liquid to the boiler tank. High liquid level in the boiler tank blocks entry of vapor into the side tube, allowing the temperature sensitive device to cool, for example, to ambient temperature.

  9. Liquid level detector

    DOE Patents [OSTI]

    Grasso, Albert P. (Vernon, CT)

    1986-01-01

    A liquid level detector for low pressure boilers. A boiler tank, from which apor, such as steam, normally exits via a main vent, is provided with a vertical side tube connected to the tank at the desired low liquid level. When the liquid level falls to the level of the side tube vapor escapes therethrough causing heating of a temperature sensitive device located in the side tube, which, for example, may activate a liquid supply means for adding liquid to the boiler tank. High liquid level in the boiler tank blocks entry of vapor into the side tube, allowing the temperature sensitive device to cool, for example, to ambient temperature.

  10. RELAP5 subcooled critical flow model verification

    SciTech Connect (OSTI)

    Petelin, S.; Gortnar, O.; Mavko, B. (Institut Jozef Stefan, Ljubljana (Solomon Islands))

    1993-01-01

    We discuss some results of the RELAP5 break modeling during the analysis of International Standard Problem 27 (ISP-27) performed on the BETHSY facility. This study deals with the discontinuity of the RELAP5 critical flow prediction in a strongly subcooled region. Such unrealistic behavior was observed during the pretest simulations of ISP-27. Based on the investigation, a RELAP5 code correction is suggested that ensures a more appropriate simulation of the critical discharge of strongly subcooled liquid.

  11. Quantum metrology in Lipkin-Meshkov-Glick critical systems

    E-Print Network [OSTI]

    Giulio Salvatori; Antonio Mandarino; Matteo G. A. Paris

    2015-04-01

    The Lipkin-Meshkov-Glick (LMG) model describes critical systems with interaction beyond the first-neighbor approximation. Here we address the characterization of LMG systems, i.e. the estimation of anisotropy, and show how criticality may be exploited to improve precision. In particular, we provide exact results for the Quantum Fisher Information of small-size LMG chains made of $N=2, 3$ and $4$ lattice sites and analyze the same quantity in the thermodynamical limit by means of a zero-th order approximation of the system Hamiltonian. We then show that the ultimate bounds to precision may be achieved by tuning the external field and by measuring the total magnetization of the system. We also address the use of LMG systems as quantum thermometers and show that: i) precision is governed by the gap between the lowest energy levels of the systems, ii) field-dependent level crossing provides a resource to extend the operating range of the quantum thermometer.

  12. Your mission-critical workloads require the highest levels of performance and security,

    E-Print Network [OSTI]

    Greenberg, Albert

    , ease of use and speed benefits of multi-tenant cloud, combined with the enterprise-grade security transform the way you deliver services to your organization. Extend the Security of your VPN IBM Cloud with the security features of an IBM cloud. Instead of using the public Internet to transport data, this "cloud

  13. Estimating polyploidy levels in fossil Salix: A critical review of cell size proxy methods

    E-Print Network [OSTI]

    Buechler, Walter K.

    2010-01-01

    L. T Wetzikon, Switzerland, 550 m /Nepal-Himalaya, 3450 mS. fragilis L. S. fragilis L. N Moenchaltorf, Switzerland NNiederuster, Switzerland C Schwerzenbach, Switzerland,

  14. Estimating polyploidy levels in fossil Salix: A critical review of cell size proxy methods

    E-Print Network [OSTI]

    Buechler, Walter K.

    2010-01-01

    F F F F F F F F F F F F F Salix / Subalbae S. babylonica L.550 m /Nepal-Himalaya, 3450 m 4 (Bue) 289 Salix /Salix S. alba L. S. fragilis L. S. fragilis L. N

  15. Estimating polyploidy levels in fossil Salix: A critical review of cell size proxy methods

    E-Print Network [OSTI]

    Buechler, Walter K.

    2010-01-01

    Salix germplasm resource reveals new insights into relationships among subgenera, sections and species. Bio Energy

  16. Tiltmeter leveling mechanism

    DOE Patents [OSTI]

    Hunter, Steven L. (Livermore, CA); Boro, Carl O. (Milpitas, CA); Farris, Alvis (late of Byron, CA)

    2002-01-01

    A tiltmeter device having a pair of orthogonally disposed tilt sensors that are levelable within an inner housing containing the sensors. An outer housing can be rotated to level at least one of the sensor pair while the inner housing can be rotated to level the other sensor of the pair. The sensors are typically rotated up to about plus or minus 100 degrees. The device is effective for measuring tilts in a wide range of angles of inclination of wells and can be employed to level a platform containing a third sensor.

  17. The Critical Mass Laboratory at Rocky Flats

    SciTech Connect (OSTI)

    Rothe, Robert E

    2003-10-15

    The Critical Mass Laboratory (CML) at Rocky Flats northwest of Denver, Colorado, was built in 1964 and commissioned to conduct nuclear experiments on January 28, 1965. It was built to attain more accurate and precise experimental data to ensure nuclear criticality safety at the plant than were previously possible. Prior to its construction, safety data were obtained from long extrapolations of subcritical data (called in situ experiments), calculated parameters from reactor engineering 'models', and a few other imprecise methods. About 1700 critical and critical-approach experiments involving several chemical forms of enriched uranium and plutonium were performed between then and 1988. These experiments included single units and arrays of fissile materials, reflected and 'bare' systems, and configurations with various degrees of moderation, as well as some containing strong neutron absorbers. In 1989, a raid by the Federal Bureau of Investigation (FBI) caused the plant as a whole to focus on 'resumption' instead of further criticality safety experiments. Though either not recognized or not admitted for a few years, that FBI raid did sound the death knell for the CML. The plant's optimistic goal of resumption evolved to one of deactivation, decommissioning, and plantwide demolition during the 1990s. The once-proud CML facility was finally demolished in April of 2002.

  18. Precision liquid level sensor

    DOE Patents [OSTI]

    Field, Michael E. (Albuquerque, NM); Sullivan, William H. (Albuquerque, NM)

    1985-01-01

    A precision liquid level sensor utilizes a balanced R. F. bridge, each arm including an air dielectric line. Changes in liquid level along one air dielectric line imbalance the bridge and create a voltage which is directly measurable across the bridge.

  19. Precision liquid level sensor

    DOE Patents [OSTI]

    Field, M.E.; Sullivan, W.H.

    1985-01-29

    A precision liquid level sensor utilizes a balanced R. F. bridge, each arm including an air dielectric line. Changes in liquid level along one air dielectric line imbalance the bridge and create a voltage which is directly measurable across the bridge. 2 figs.

  20. Fuel Cells for Critical Communications Backup Power | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cells for Critical Communications Backup Power Fuel Cells for Critical Communications Backup Power This presentation provides information about using fuel cells for emergency...

  1. Critical Materials Research in DOE Video (Text Version)

    Broader source: Energy.gov [DOE]

    This is a text version of the "Critical Materials Research in DOE" video presented at the Critical Materials Workshop, held on April 3, 2012 in Arlington, Virginia.

  2. Department of Energy Critical Materials Strategy Video (Text Version)

    Broader source: Energy.gov [DOE]

    This is a text version of the "Department of Energy Critical Materials Strategy" video presented at the Critical Materials Workshop, held on April 3, 2012 in Arlington, Virginia.

  3. CNG, Hydrogen, CNG-Hydrogen Blends - Critical Fuel Properties...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    CNG, Hydrogen, CNG-Hydrogen Blends - Critical Fuel Properties and Behavior CNG, Hydrogen, CNG-Hydrogen Blends - Critical Fuel Properties and Behavior Presentation given by Jay...

  4. The Critical Materials Institute announces two new industry members...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The Critical Materials Institute announces two new industry members Contacts: For release: Aug. 18, 2015 Alex King, Director, Critical Materials Institute, (515) 296-4505 Laura...

  5. Critical Materials Institute's rare-earth recycling tech goes...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Critical Materials Institute's rare-earth recycling tech goes commercial OAK RIDGE, Tenn., Aug. 10, 2015-The Critical Materials Institute is celebrating its first commercial...

  6. Effects of Ignition Quality and Fuel Composition on Critical...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ignition Quality and Fuel Composition on Critical Equivalence Ratio Effects of Ignition Quality and Fuel Composition on Critical Equivalence Ratio Our research shows that fuel can...

  7. DOE NSF Partnership to Address Critical Challenges in Hydrogen...

    Office of Environmental Management (EM)

    NSF Partnership to Address Critical Challenges in Hydrogen Production from Solar Water Splitting DOE NSF Partnership to Address Critical Challenges in Hydrogen Production from...

  8. National Academies Criticality Methodology and Assessment Video (Text Version)

    Broader source: Energy.gov [DOE]

    This is a text version of the "National Academies Criticality Methodology and Assessment" video presented at the Critical Materials Workshop, held on April 3, 2012 in Arlington, Virginia.

  9. NIST Roadmap for Improving Critical Infrastructure Cybersecurity February 12, 2014

    E-Print Network [OSTI]

    NIST Roadmap for Improving Critical Infrastructure Cybersecurity February 12, 2014 1. Introduction This companion Roadmap to the Framework for Improving Critical Infrastructure Cybersecurity ("the

  10. The Department of Energy Releases Strategy on Critical Materials...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Department of Energy Releases Strategy on Critical Materials The Department of Energy Releases Strategy on Critical Materials December 15, 2010 - 12:00am Addthis The Department...

  11. President's 2014 Budget Proposes Critical Investments in Clean...

    Energy Savers [EERE]

    President's 2014 Budget Proposes Critical Investments in Clean Energy President's 2014 Budget Proposes Critical Investments in Clean Energy April 17, 2013 - 2:01pm Addthis...

  12. Multiple Critical Points in Effective Quark Models

    E-Print Network [OSTI]

    Ferroni, Lorenzo; Pinto, Marcus B

    2010-01-01

    We consider the two flavor version of the Linear Sigma Model as well as of the Nambu Jona-Lasinio model, at finite temperature and quark chemical potential, beyond the Mean Field Approximation. Using parameter values for the pion and quark current masses which weakly break chiral symmetry we show that both models can present more than one critical end point. In particular, we explicitly show that the appearance of a new critical point associated with a first order line at high temperature and low densities could help to conciliate some lattice results with model predictions. Using different techniques, we perform an extensive thermodynamical analysis to understand the physical nature of the different critical points. For both models, our results suggest that the new first order line which starts at vanishing chemical potential has a more chiral character than the usual line which displays a character more reminiscent of a liquid-gas phase transition.

  13. Dynamic trapping near a quantum critical point

    E-Print Network [OSTI]

    Michael Kolodrubetz; Emanuel Katz; Anatoli Polkovnikov

    2015-03-02

    The study of dynamics in closed quantum systems has recently been revitalized by the emergence of experimental systems that are well-isolated from their environment. In this paper, we consider the closed-system dynamics of an archetypal model: spins near a second order quantum critical point, which are traditionally described by the Kibble-Zurek mechanism. Imbuing the driving field with Newtonian dynamics, we find that the full closed system exhibits a robust new phenomenon -- dynamic critical trapping -- in which the system is self-trapped near the critical point due to efficient absorption of field kinetic energy by heating the quantum spins. We quantify limits in which this phenomenon can be observed and generalize these results by developing a Kibble-Zurek scaling theory that incorporates the dynamic field. Our findings can potentially be interesting in the context of early universe physics, where the role of the driving field is played by the inflaton or a modulus.

  14. Variable-Temperature Critical-Current Measurements

    SciTech Connect (OSTI)

    L. F. Goodrich; T. C. Stauffer

    2009-05-19

    This is the final report of a three year contract that covered 09/19/2005 to 07/14/2008. We requested and received a no cost time extension for the third year, 07/15/2007 to 07/14/2008, to allow DoE to send us funds if they became available during that year. It turned out that we did not receive any funding for the third year. The following paper covers our variable-temperature critical-current measurements. We made transport critical-current (Ic) measurements on commercial multifilamentary Nb3Sn strands at temperatures (T) from 4 to 17 K and magnetic fields (H) from 0 to 14 T. One of the unique features of our measurements is that we can cover a wide range of critical currents from less than 0.1 A to over 700 A.

  15. Criticality Safety Basics for INL Emergency Responders

    SciTech Connect (OSTI)

    Valerie L. Putman

    2012-08-01

    This document is a modular self-study guide about criticality safety principles for Idaho National Laboratory emergency responders. This guide provides basic criticality safety information for people who, in response to an emergency, might enter an area that contains much fissionable (or fissile) material. The information should help responders understand unique factors that might be important in responding to a criticality accident or in preventing a criticality accident while responding to a different emergency.

    This study guide specifically supplements web-based training for firefighters (0INL1226) and includes information for other Idaho National Laboratory first responders. However, the guide audience also includes other first responders such as radiological control personnel.

    For interested readers, this guide includes clearly marked additional information that will not be included on tests. The additional information includes historical examples (Been there. Done that.), as well as facts and more in-depth information (Did you know …).

    INL criticality safety personnel revise this guide as needed to reflect program changes, user requests, and better information. Revision 0, issued May 2007, established the basic text. Revision 1 incorporates operation, program, and training changes implemented since 2007. Revision 1 increases focus on first responders because later responders are more likely to have more assistance and guidance from facility personnel and subject matter experts. Revision 1 also completely reorganized the training to better emphasize physical concepts behind the criticality controls that help keep emergency responders safe. The changes are based on and consistent with changes made to course 0INL1226.

  16. A primer for criticality calculations with DANTSYS

    SciTech Connect (OSTI)

    Busch, R.D.

    1997-08-01

    With the closure of many experimental facilities, the nuclear safety analyst has to rely on computer calculations to identify safe limits for the handling and storage of fissile materials. Although deterministic methods often do not provide exact models of a system, a substantial amount of reliable information on nuclear systems can be obtained using these methods if the user understands their limitations. To guide criticality specialists in this area, the Nuclear Criticality Safety Group at the University of New Mexico (UNM) in cooperation with the Radiation Transport Group at Los Alamos National Laboratory (LANL) has designed a primer to help the analyst understand and use the DANTSYS deterministic transport code for nuclear criticality safety analyses. DANTSYS is the new name of the group of codes formerly known as: ONEDANT, TWODANT, TWOHEX, TWOGQ, and THREEDANT. The primer is designed to teach bu example, with each example illustrating two or three DANTSYS features useful in criticality analyses. Starting with a Quickstart chapter, the primer gives an overview of the basic requirements for DANTSYS input and allows the user to quickly run a simple criticality problem with DANTSYS. Each chapter has a list of basic objectives at the beginning identifying the goal of the chapter and the individual DANTSYS features covered in detail in the chapter example problems. On completion of the primer, it is expected that the user will be comfortable doing criticality calculations with DANTSYS and can handle 60--80% of the situations that normally arise in a facility. The primary provides a set of input files that can be selective modified by the user to fit each particular problem.

  17. Partitioned Scheduling of Multi-Modal Mixed-Criticality Real-Time Systems on Multiprocessor Platforms

    E-Print Network [OSTI]

    Plotkin, Joshua B.

    ). Motivating example. Consider an automotive system that ex- ecutes four tasks on a two-processor platform: p Platforms Dionisio de Niz SEI, Carnegie Mellon University Linh T.X. Phan University of Pennsylvania Abstract safety- criticality levels. For instance, the automotive certification standard ISO 26262 [15] identifies

  18. QCD Critical Point: The Race is On

    E-Print Network [OSTI]

    Gavai, Rajiv V

    2014-01-01

    A critical point in the phase diagram of Quantum Chromodynamics (QCD), if established either theoretically or experimentally, would be as profound a discovery as the good-old gas-liquid critical point. Unlike the latter, however, first-principles based approaches are being employed to locate it theoretically. Due to the short lived nature of the concerned phases, novel experimental techniques are needed to search for it. The Relativistic Heavy Ion Collider (RHIC) in USA has an experimental program to do so. This short review is an attempt to provide a glimpse of the race between the theorists and the experimentalists as well as that of the synergy between them.

  19. Critical Masses for Unreflected Metal Spheres

    SciTech Connect (OSTI)

    Westfall, Robert Michael; Wright, Richard Q

    2009-01-01

    Calculated critical masses of bare metal spheres for 28 actinide isotopes, using the SCALE/XSDRNPM one-dimensional, discrete-ordinates system, are presented. ENDF/B-VI, ENDF/B-VII, and JENDL-3.3 cross sections were used in the calculations. Results are given for isotopes of uranium, neptunium, plutonium, americium, curium, californium, and for one isotope of einsteinium. Calculated k values for these same nuclides are also given. We show that, for non-threshold or low-threshold fission nuclides, a good approximation for the nuclide k is the value of nubar at 1 MeV. A plot of the critical mass versus k values is given for 19 nuclides with A-numbers between 232 and 250. The peaks in the critical mass curve (for seven nuclides) correspond to dips in the k curve. For the seven cases with the largest critical mass, six are even-even nuclides. Neptunium-237, with a critical mass of about 62.7 kg (ENDF/B-VI calculation), has an odd number of protons and an even number of neutrons. However, two cases with quite small critical masses, 232U and 236Pu, are also even-even. These two nuclides do not exhibit threshold fission behavior like most other even-even nuclides. The largest critical mass is 208.8 kg for 243Am and the smallest is 2.44 kg for 251Cf. The calculated k values vary from 1.5022 for 234U to 4.4767 for 251Cf. A correlation between the calculated critical mass (kg) and the fission spectrum averaged value of is given for the elements U, Np, Pu, Am, Cm, and Cf. For each of the five elements, a fit to the data for that element is provided. In each case the fit employs a negative exponential of the form mass = exp(A + B ~ ln( ) The values of A and B are element dependent and vary slightly for each of the five elements. The method described here is mainly applicable for non-threshold fission nuclides (15 of the 28 nuclides considered in this paper). There are three exceptions, 238Pu, 244Cm, and 250Cf, which all exhibit threshold fission behavior.

  20. HANFORD NUCLEAR CRITICALITY SAFETY PROGRAM DATABASE

    SciTech Connect (OSTI)

    TOFFER, H.

    2005-05-02

    The Hanford Database is a useful information retrieval tool for a criticality safety practitioner. The database contains nuclear criticality literature screened for parameter studies. The entries, characterized with a value index, are segregated into 16 major and six minor categories. A majority of the screened entries have abstracts and a limited number are connected to the Office of Scientific and Technology Information (OSTI) database of full-size documents. Simple and complex searches of the data can be accomplished very rapidly and the end-product of the searches could be a full-size document. The paper contains a description of the database, user instructions, and a number of examples.

  1. Analysis of Godiva-IV delayed-critical and static super-prompt-critical conditions

    SciTech Connect (OSTI)

    Mosteller, Russell D; Goda, Joetta M

    2009-01-01

    Super-prompt-critical burst experiments were conducted on the Godiva-IV assembly at Los Alamos National Laboratory from the 1960s through 2005. Detailed and simplified benchmark models have been constructed for four delayed-critical experiments and for the static phase of a super-prompt-critical burst experiment. In addition, a two-dimensional cylindrical model has been developed for the super-prompt-critical condition. Criticality calculations have been performed for all of those models with four modern nuclear data libraries: ENDFIB-VI, ENDF/8-VII.0, JEFF-3.1 , and JENDL-3.3. Overall, JENDL-3.3 produces the best agreement with the reference values for k{sub eff}.

  2. Critical Incident Stress Management (CISM): Group Crisis Intervention, 4th June 2006, International Critical Incident Stress Foundation, Inc.

    E-Print Network [OSTI]

    Oliver, Douglas L.

    Critical Incident Stress Management (CISM): Group Crisis Intervention, 4th Edition, June 2006 Management (CISM): Group Crisis Intervention, 4th Edition, June 2006, International Critical Incident Stress

  3. Energy level alignment of polythiophene/ZnO hybrid solar cells

    E-Print Network [OSTI]

    Garfunkel, Eric

    Energy level alignment of polythiophene/ZnO hybrid solar cells W. Feng,a S. Rangan,b Y. Cao,c E between energy level alignment and photovoltaic properties of a model bilayer hybrid solar cell. Galoppini,c R. A. Bartynskib and E. Garfunkel*ab Energy level alignment at interfaces is critical

  4. Introduction Critically ill patients requiring mechanical venti-

    E-Print Network [OSTI]

    Young, Todd

    Introduction Critically ill patients requiring mechanical venti- lation are at significant risk techniques are generally, invasive, labor inten- sive and slow [1, 9]. The culture delay often pro- motes unnecessary antibiotic exposure with an associated increased risk of both subsequent infectious complications

  5. Autonomous Following RObot Critical Design Review

    E-Print Network [OSTI]

    Liebling, Michael

    , tennis, football, soccer Repainting fading street lines Perimeter security Warehouse item retrieval/storage user input. Navigating to specific coordinates of a grid. #12;Critical Design Review: Project - schematic/PCB, digital compass Travis - mechanical - servo, reflective sensor, power Peter - mechanical

  6. Timely PTS Applications Critical to Staying Navy

    E-Print Network [OSTI]

    Timely PTS Applications Critical to Staying Navy Navy Personnel Command (NPC) is reminding commands and Sailors that submitting Perform to Serve (PTS) applications is the key to being able to stay Navy/10 explains how PTS is used to shape the Navy, and includes all business rules concerning. Commands must

  7. Critical point analysis of phase envelope diagram

    SciTech Connect (OSTI)

    Soetikno, Darmadi; Siagian, Ucok W. R.; Kusdiantara, Rudy Puspita, Dila Sidarto, Kuntjoro A. Soewono, Edy; Gunawan, Agus Y.

    2014-03-24

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab.

  8. Geological carbon sequestration: critical legal issues

    E-Print Network [OSTI]

    Watson, Andrew

    Geological carbon sequestration: critical legal issues Ray Purdy and Richard Macrory January 2004 Tyndall Centre for Climate Change Research Working Paper 45 #12;1 Geological carbon sequestration an integrated assessment of geological carbon sequestration (Project ID code T2.21). #12;2 1 Introduction

  9. Criticality calculations for Step-2 GPHS modules.

    SciTech Connect (OSTI)

    Hensen, Danielle Lynn; Lipinski, Ronald J.

    2007-08-01

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) will use an improved version of the General Purpose Heat Source (GPHS) module as its source of thermal power. This new version, referred to as the Step-2 GPHS Module, has additional and thicker layers of carbon fiber material (Fine Weaved Pierced Fabric) for increased strength over the original GPHS module. The GPHS uses alpha decay of {sup 238}Pu in the oxide form as the primary source of heat, and small amounts of other actinides are also present in the oxide fuel. Criticality calculations have been performed by previous researchers on the original version of the GPHS module (Step 0). This paper presents criticality calculations for the present Step-2 version. The Monte Carlo N-Particle eXtended code (MCNPX) was used for these calculations. Numerous configurations of GPHS module arrays surrounded by wet sand and other materials (to reflect the neutrons back into the stack with minimal absorption) were modeled. For geometries with eight GPHS modules (from a single MMRTG) surrounded by wet sand, the configuration is extremely sub-critical; k{sub eff} is about 0.3. It requires about 1000 GPHS modules (from 125 MMRTGs) in a close-spaced stack to approach criticality (k{sub eff} = 1.0) when surrounded by wet sand. The effect of beryllium in the MMRTG was found to be relatively small.

  10. Criticality Calculations for Step-2 GPHS Modules

    SciTech Connect (OSTI)

    Lipinski, Ronald J. [Advanced Nuclear Concepts Department, Sandia National Laboratories, P.O Box 5800, Albuquerque, NM 87185 (United States); Hensen, Danielle L. [Risk and Reliability Department Sandia National Laboratories, P.O Box 5800, Albuquerque, NM 87185 (United States)

    2008-01-21

    The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) will use an improved version of the General Purpose Heat Source (GPHS) module as its source of thermal power. This new version, referred to as the Step-2 GPHS Module, has additional and thicker layers of carbon fiber material (Fine Weaved Pierced Fabric) for increased strength over the original GPHS module. The GPHS uses alpha decay of {sup 238}Pu in the oxide form as the primary source of heat, and small amounts of other actinides are also present in the oxide fuel. Criticality calculations have been performed by previous researchers on the original version of the GPHS module (Step 0). This paper presents criticality calculations for the present Step-2 version. The Monte Carlo N-Particle eXtended code (MCNPX) was used for these calculations. Numerous configurations of GPHS module arrays surrounded by wet sand and other materials (to reflect the neutrons back into the stack with minimal absorption) were modeled. For geometries with eight GPHS modules (from a single MMRTG) surrounded by wet sand, the configuration is extremely sub-critical; k{sub eff} is about 0.3. It requires about 1000 GPHS modules (from 125 MMRTGs) in a close-spaced stack to approach criticality (k{sub eff} = 1.0) when surrounded by wet sand. The effect of beryllium in the MMRTG was found to be relatively small.

  11. Institute for Critical Technology and Applied Science

    E-Print Network [OSTI]

    Crawford, T. Daniel

    and a Polymer Engineer with Michelin Americas Research and Development Corporation in Greenville, SC. He has hadInstitute for Critical Technology and Applied Science www.ictas.vt.edu NEW HORIZONS ICTAS SEMINAR) 3. CBET-Broadening Participation Research Initiation Grant in Engineering Program (BRIGE) 4. Science

  12. Determination of Critical Exponents in Nuclear Systems

    E-Print Network [OSTI]

    W. F. J. Mueller; ALADIN collaboration

    1996-07-08

    Signatures of critical behaviour in nuclear fragmentation are often based on arguments from percolation theory. We demonstrate with general thermodynamic considerations and studies of the Ising model that the reliance on percolation as a reference model bears the risk of missing parts of the essential physics.

  13. Derived critical loci I -Basics Gabriele Vezzosi

    E-Print Network [OSTI]

    Vezzosi, Gabriele

    Derived critical loci I - Basics Gabriele Vezzosi Dipartimento di Sistemi ed Informatica Universit`a di Firenze Italy Notes ­ September 2011 Contents 1 Introduction 1 2 Koszul complexes and derived zero . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2.2 Affine derived zero loci . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2

  14. Governance Level Principle 2 Risk Management Relevant UTAS

    E-Print Network [OSTI]

    Wapstra, Erik

    Governance Level Principle 2 ­ Risk Management Relevant UTAS Ordinance and/or Rule Reference No Review Date Review 1 - December 2011 Review 2 - December 2016 1. Statement of Context Risk management of risks from external and internal sources. Being risk aware and managing these risk is critical

  15. Multi-Level Alert Clustering for Intrusion Detection Sensor Data*

    E-Print Network [OSTI]

    Siraj, Ambareen

    multiple, diverse sensors. Intelligent sensor fusion of runtime behavior data is critical for such systemsMulti-Level Alert Clustering for Intrusion Detection Sensor Data* Ambareen Siraj Rayford B. Vaughn sensors that monitor security violations throughout the network. The outputs of the sensors must be fused

  16. Review of Yucca Mountain Disposal Criticality Studies

    SciTech Connect (OSTI)

    Scaglione, John M [ORNL] [ORNL; Wagner, John C [ORNL] [ORNL

    2011-01-01

    The U.S. Department of Energy (DOE), Office of Civilian Radioactive Waste Management, submitted a license application for construction authorization of a deep geologic repository at Yucca Mountain, Nevada, in June of 2008. The license application is currently under review by the U.S. Nuclear Regulatory Commission. However,on March 3, 2010 the DOE filed a motion requesting withdrawal of the license application. With the withdrawal request and the development of the Blue Ribbon Commission to seek alternative strategies for disposing of spent fuel, the status of the proposed repository at Yucca Mountain is uncertain. What is certain is that spent nuclear fuel (SNF) will continue to be generated and some long-lived components of the SNF will eventually need a disposition path(s). Strategies for the back end of the fuel cycle will continue to be developed and need to include the insights from the experience gained during the development of the Yucca Mountain license application. Detailed studies were performed and considerable progress was made in many key areas in terms of increased understanding of relevant phenomena and issues regarding geologic disposal of SNF. This paper reviews selected technical studies performed in support of the disposal criticality analysis licensing basis and the use of burnup credit. Topics include assembly misload analysis, isotopic and criticality validation, commercial reactor critical analyses, loading curves, alternative waste package and criticality control studies, radial burnup data and effects, and implementation of a conservative application model in the criticality probabilistic evaluation as well as other information that is applicable to operations regarding spent fuel outside the reactor. This paper summarizes the work and significant accomplishments in these areas and provides a resource for future, related activities.

  17. Early Warning Signals for Critical Transitions: A Generalized Modeling Approach

    E-Print Network [OSTI]

    rangelands [9], and desertification [10]. Warning signals for impending critical transitions are highly

  18. Radiation monitoring during criticality at a gaseous diffusion plant

    SciTech Connect (OSTI)

    Goebel, G.R.; Hines, T.W.; Carver, A.M.

    1994-12-31

    The Paducah gaseous diffusion plant (PGDP) has two systems of radiation detection units that monitor radiation associated with a nuclear criticality accident (NCA). The primary system, the criticality accident alarm system (CAAS), is composed of several detection units that alarm when gamma-radiation levels exceed 10 mR/h. The CAAS provides the means to initiate emergency-evacuation procedures in the event of an NCA. This system is augmented with a second system of radiation detectors, which is referred to as the argon gamma graph (AGG) system. The AGG system is utilized specifically for the remote monitoring of radiation during an NCA and is a primary tool used by emergency response personnel. The remote radiation readings supplied by the AGG system provide the means to quickly locate and characterize an NCA. The centralized remote monitoring of radiation during an NCA permits important data to be collected efficiently without subjecting personnel to unknown and unquantified radiation fields. Calculations of the expected radiation readings on the AGG system were performed for a postulated NCA at four different locations at PGDP.

  19. Critical entanglement spectrum of one-dimensional symmetry protected topological phases

    E-Print Network [OSTI]

    Wen-Jia Rao; Xin Wan; Guang-Ming Zhang

    2014-09-01

    Under an appropriate symmetric extensive bipartition in a one-dimensional symmetry protected topological (SPT) phase, a bulk critical entanglement spectrum can be obtained, resembling the excitation spectrum of the critical point separating the SPT phase from the trivial (vacuum) state. Such a critical point is beyond the standard Landau-Ginzburg-Wilson paradigm for symmetry breaking phase transitions. For the $S=1$ SPT (Haldane) phase with the Affleck-Kennedy-Lieb-Tasaki exact wave function, the resulting critical entanglement spectrum has a residual entropy per lattice site $s_{r}=0.67602$, showing a delocalized version of the edge excitations in the SPT phase. From the wave function corresponding to the lowest entanglement energy level, the central charge of the critical point can be extracted $c\\approx 1.01\\pm 0.01$. The critical theory can be identified as the same effective field theory as the spin-1/2 antiferromagnetic Heisenberg chain or the spin-1/2 Haldane-Shastry model with inverse square long-range interaction.

  20. Extreme hydrodynamic atmospheric loss near the critical thermal escape regime

    E-Print Network [OSTI]

    Erkaev, N V; Odert, P; Kulikov, Yu N; Kislyakova, K G

    2015-01-01

    By considering martian-like planetary embryos inside the habitable zone of solar-like stars we study the behavior of the hydrodynamic atmospheric escape of hydrogen for small values of the Jeans escape parameter $\\beta thermal energy. Our study is based on a 1-D hydrodynamic upper atmosphere model that calculates the volume heating rate in a hydrogen dominated thermosphere due to the absorption of the stellar soft X-ray and extreme ultraviolet (XUV) flux. We find that when the $\\beta$ value near the mesopause/homopause level exceeds a critical value of $\\sim$2.5, there exists a steady hydrodynamic solution with a smooth transition from subsonic to supersonic flow. For a fixed XUV flux, the escape rate of the upper atmosphere is an increasing function of the temperature at the lower boundary. Our model results indicate a crucial enhancement of the atmospheric escape rate, when the Jeans escape parameter $\\beta$ decr...

  1. Ultrasonic liquid level detector

    DOE Patents [OSTI]

    Kotz, Dennis M. (North Augusta, SC); Hinz, William R. (Augusta, GA)

    2010-09-28

    An ultrasonic liquid level detector for use within a shielded container, the detector being tubular in shape with a chamber at its lower end into which liquid from in the container may enter and exit, the chamber having an ultrasonic transmitter and receiver in its top wall and a reflector plate or target as its bottom wall whereby when liquid fills the chamber a complete medium is then present through which an ultrasonic wave may be transmitted and reflected from the target thus signaling that the liquid is at chamber level.

  2. Automated Critical Peak Pricing Field Tests: Program Descriptionand Results

    SciTech Connect (OSTI)

    Piette, Mary Ann; Watson, David; Motegi, Naoya; Kiliccote, Sila; Xu, Peng

    2006-04-06

    California utilities have been exploring the use of critical peak prices (CPP) to help reduce needle peaks in customer end-use loads. CPP is a form of price-responsive demand response (DR). Recent experience has shown that customers have limited knowledge of how to operate their facilities in order to reduce their electricity costs under CPP (Quantum 2004). While the lack of knowledge about how to develop and implement DR control strategies is a barrier to participation in DR programs like CPP, another barrier is the lack of automation of DR systems. During 2003 and 2004, the PIER Demand Response Research Center (DRRC) conducted a series of tests of fully automated electric demand response (Auto-DR) at 18 facilities. Overall, the average of the site-specific average coincident demand reductions was 8% from a variety of building types and facilities. Many electricity customers have suggested that automation will help them institutionalize their electric demand savings and improve their overall response and DR repeatability. This report focuses on and discusses the specific results of the Automated Critical Peak Pricing (Auto-CPP, a specific type of Auto-DR) tests that took place during 2005, which build on the automated demand response (Auto-DR) research conducted through PIER and the DRRC in 2003 and 2004. The long-term goal of this project is to understand the technical opportunities of automating demand response and to remove technical and market impediments to large-scale implementation of automated demand response (Auto-DR) in buildings and industry. A second goal of this research is to understand and identify best practices for DR strategies and opportunities. The specific objectives of the Automated Critical Peak Pricing test were as follows: (1) Demonstrate how an automated notification system for critical peak pricing can be used in large commercial facilities for demand response (DR). (2) Evaluate effectiveness of such a system. (3) Determine how customers will respond to this form of automation for CPP. (4) Evaluate what type of DR shifting and shedding strategies can be automated. (5) Explore how automation of control strategies can increase participation rates and DR saving levels with CPP. (6) Identify optimal demand response control strategies. (7) Determine occupant and tenant response.

  3. History of critical experiments at Pajarito Site

    SciTech Connect (OSTI)

    Paxton, H.C.

    1983-03-01

    This account describes critical and subcritical assemblies operated remotely at the Pajarito Canyon Site at the Los Alamos National Laboratory. Earliest assemblies, directed exclusively toward the nuclear weapons program, were for safety tests. Other weapon-related assemblies provided neutronic information to check detailed weapon calculations. Topsy, the first of these critical assemblies, was followed by Lady Godiva, Jezebel, Flattop, and ultimately Big Ten. As reactor programs came to Los Alamos, design studies and mockups were tested at Pajarito Site. For example, nearly all 16 Rover reactors intended for Nevada tests were preceded by zero-power mockups and proof tests at Pajarito Site. Expanded interest and capability led to fast-pulse assemblies, culminating in Godiva IV and Skua, and to the Kinglet and Sheba solution assemblies.

  4. Refined critical balance in strong Alfvenic turbulence

    E-Print Network [OSTI]

    A. Mallet; A. A. Schekochihin; B. D. G. Chandran

    2015-08-24

    We present numerical evidence that in strong Alfvenic turbulence, the critical balance principle---equality of the nonlinear decorrelation and linear propagation times---is scale invariant, in the sense that the probability distribution of the ratio of these times is independent of scale. This result only holds if the local alignment of the Elsasser fields is taken into account in calculating the nonlinear time. At any given scale, the degree of alignment is found to increase with fluctuation amplitude, supporting the idea that the cause of alignment is mutual dynamical shearing of Elsasser fields. The scale-invariance of critical balance (while all other quantities of interest are strongly intermittent, i.e., have scale-dependent distributions) suggests that it is the most robust of the scaling principles used to describe Alfvenic turbulence. The quality afforded by situ fluctuation measurements in the solar wind allows for direct verification of this fundamental principle.

  5. Architecture for high critical current superconducting tapes

    DOE Patents [OSTI]

    Jia, Quanxi (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM)

    2002-01-01

    Improvements in critical current capacity for superconducting film structures are disclosed and include the use of, e.g., multilayer YBCO structures where individual YBCO layers are separated by a layer of an insulating material such as CeO.sub.2 and the like, a layer of a conducting material such as strontium ruthenium oxide and the like or by a second superconducting material such as SmBCO and the like.

  6. EPR and Bell's theorem: A critical review

    SciTech Connect (OSTI)

    Stapp, H.P. (Lawrence Berkeley Lab., CA (United States))

    1991-01-01

    The argument of Einstein, Podolsky, and Rosen is reviewed with attention to logical structure and character of assumptions. Bohr's reply is discussed. Bell's contribution is formulated without use of hidden variables, and efforts to equate hidden variables to realism are critically examined. An alternative derivation of nonlocality that makes no use of hidden variables, microrealism, counterfactual definiteness, or any other assumption alien to orthodox quantum thinking is described in detail, with particular attention to the quartet or broken-square question.

  7. Critical regimes of internal gravity wave generation

    E-Print Network [OSTI]

    Vitaly V. Bulatov; Yuriy V. Vladimirov; Vasily A. Vakorin

    2005-11-27

    The problem of constructing an asymptotic representation of the solution of the internal gravity wave field exited by a source moving at a velocity close to the maximum group velocity of the individual wave mode is considered. For the critical regimes of individual mode generation the asymptotic representation of the solution obtained is expressed in terms of a zero-order Macdonald function. The results of numerical calculations based on the exact and asymptotic formulas are given.

  8. Apparatus and method for critical current measurements

    DOE Patents [OSTI]

    Martin, Joe A. (Espanola, NM); Dye, Robert C. (Los Alamos, NM)

    1992-01-01

    An apparatus for the measurement of the critical current of a superconductive sample, e.g., a clad superconductive sample, the apparatus including a conductive coil, a means for maintaining the coil in proximity to a superconductive sample, an electrical connection means for passing a low amplitude alternating current through the coil, a cooling means for maintaining the superconductive sample at a preselected temperature, a means for passing a current through the superconductive sample, and, a means for monitoring reactance of the coil, is disclosed, together with a process of measuring the critical current of a superconductive material, e.g., a clad superconductive material, by placing a superconductive material into the vicinity of the conductive coil of such an apparatus, cooling the superconductive material to a preselected temperature, passing a low amplitude alternating current through the coil, the alternating current capable of generating a magnetic field sufficient to penetrate, e.g., any cladding, and to induce eddy currents in the superconductive material, passing a steadily increasing current through the superconductive material, the current characterized as having a different frequency than the alternating current, and, monitoring the reactance of the coil with a phase sensitive detector as the current passed through the superconductive material is steadily increased whereby critical current of the superconductive material can be observed as the point whereat a component of impedance deviates.

  9. Critical Masses for Unreflected Metal Spheres

    SciTech Connect (OSTI)

    Westfall, Robert Michael; Goluoglu, Sedat; Wright, Richard Q

    2009-01-01

    Critical masses of bare metal spheres for 33 actinide isotopes, using the SCALE/XSDRNPM one-dimensional, discrete-ordinates system, are presented. ENDF/B-VI, ENDF/B-VII, and JENDL-3.3 cross sections were used in the calculations. Results are given for isotopes of U, Np, Pu, Am, Cm, and Cf and for one isotope of Es. Calculated k-infinity values for 41 actinides are also given. For the nonthreshold or low-threshold fission nuclides, a good approximation for the nuclide k-infinity is the value of nubar at 1 MeV. A correlation between the calculated critical mass (kg) and the fission spectrum averaged value of F is given for the elements U, Np, Pu, Cm, and Cf as CM (kg) = exp (A + B ln( F)).(1) The values of A and B are element dependent and vary slightly for each of the five elements. The method described here is mainly applicable for nonthreshold fission nuclides (15 of the 31 nuclides considered in this paper). We conclude that equation (1) is useful for predicting the critical mass for nonthreshold fission nuclides if we have accurate values of the fission spectrum averaged F.

  10. CMI Membership Program | Critical Materials Institute

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    CMI Advisory Board and Director. This level of participation is required to sign CMI's Master Non-disclosure Agreement and the Intellectual Property Management Plan (IPMP)....

  11. IReliability Failure Mode, Effects and Criticality Analysis

    E-Print Network [OSTI]

    Rathbun, Julie A.

    the system FMECA for the PSE included in A TM 501 B. The component level FMEA is given in a Teledyne ~ocument

  12. LEVEL 01 FLOOR LEVEL 1 / GROUND FLOOR / SUPPORT SERVICES BUILDING

    E-Print Network [OSTI]

    Lennard, William N.

    LEVEL 01 FLOOR LEVEL 1 / GROUND FLOOR / SUPPORT SERVICES BUILDING 05/02/2012ACCESSIBILITY WESTERN FLOOR PLAN SUPPORT SERVICES BUILDING Level 2 Lower building Rm.2350 1393 WESTERN ROAD N6G -1G9 UPDATE DRAWN #12;LEVEL 02 FLOOR LEVEL 2 / SECOND FLOOR / SUPPORT SERVICES BUILDING 05/02/2012ACCESSIBILITY

  13. CRITICALITY SAFETY OF PROCESSING SALT SOLUTION AT SRS

    SciTech Connect (OSTI)

    Stephens, K; Davoud Eghbali, D; Michelle Abney, M

    2008-01-15

    High level radioactive liquid waste generated as a result of the production of nuclear material for the United States defense program at the Savannah River Site has been stored as 36 million gallons in underground tanks. About ten percent of the waste volume is sludge, composed of insoluble metal hydroxides primarily hydroxides of Mn, Fe, Al, Hg, and most radionuclides including fission products. The remaining ninety percent of the waste volume is saltcake, composed of primarily sodium (nitrites, nitrates, and aluminates) and hydroxides. Saltcakes account for 30% of the radioactivity while the sludge accounts for 70% of the radioactivity. A pilot plant salt disposition processing system has been designed at the Savannah River Site for interim processing of salt solution and is composed of two facilities: the Actinide Removal Process Facility (ARPF) and the Modular Caustic Side Solvent Extraction Unit (MCU). Data from the pilot plant salt processing system will be used for future processing salt at a much higher rate in a new salt processing facility. Saltcake contains significant amounts of actinides, and other long-lived radioactive nuclides such as strontium and cesium that must be extracted prior to disposal as low level waste. The extracted radioactive nuclides will be mixed with the sludge from waste tanks and vitrified in another facility. Because of the presence of highly enriched uranium in the saltcake, there is a criticality concern associated with concentration and/or accumulation of fissionable material in the ARP and MCU.

  14. CriTi-CAL: A computer program for Critical Coiled Tubing Calculations

    SciTech Connect (OSTI)

    He, X.

    1995-12-31

    A computer software package for simulating coiled tubing operations has been developed at Rogaland Research. The software is named CriTiCAL, for Critical Coiled Tubing Calculations. It is a PC program running under Microsoft Windows. CriTi-CAL is designed for predicting force, stress, torque, lockup, circulation pressure losses and along-hole-depth corrections for coiled tubing workover and drilling operations. CriTi-CAL features an user-friendly interface, integrated work string and survey editors, flexible input units and output format, on-line documentation and extensive error trapping. CriTi-CAL was developed by using a combination of Visual Basic and C. Such an approach is an effective way to quickly develop high quality small to medium size software for the oil industry. The software is based on the results of intensive experimental and theoretical studies on buckling and post-buckling of coiled tubing at Rogaland Research. The software has been validated by full-scale test results and field data.

  15. Approaches to acceptable risk: a critical guide

    SciTech Connect (OSTI)

    Fischhoff, B.; Lichtenstein, S.; Slovic, P.; Keeney, R.; Derby, S.

    1980-12-01

    Acceptable-risk decisions are an essential step in the management of technological hazards. In many situations, they constitute the weak (or missing) link in the management process. The absence of an adequate decision-making methodology often produces indecision, inconsistency, and dissatisfaction. The result is neither good for hazard management nor good for society. This report offers a critical analysis of the viability of various approaches as guides to acceptable-risk decisions. This report seeks to define acceptable-risk decisions and to examine some frequently proposed, but inappropriate, solutions. 255 refs., 22 figs., 25 tabs.

  16. Disentanglement in a quantum critical environment

    E-Print Network [OSTI]

    Zhe Sun; Xiaoguang Wang; C. P. Sun

    2007-04-10

    We study the dynamical process of disentanglement of two qubits and two qutrits coupled to an Ising spin chain in a transverse field, which exhibits a quantum phase transition. We use the concurrence and negativity to quantify entanglement of two qubits and two qutrits, respectively. Explicit connections between the concurrence (negativity) and the decoherence factors are given for two initial states, the pure maximally entangled state and the mixed Werner state. We find that the concurrence and negativity decay exponentially with fourth power of time in the vicinity of critical point of the environmental system.

  17. Traveling water waves with critical layers

    E-Print Network [OSTI]

    Ailo Aasen; Kristoffer Varholm

    2015-08-19

    We establish the existence of small-amplitude uni- and bimodal steady periodic gravity waves with an affine vorticity distribution. The solutions describe waves with critical layers and an arbitrary number of crests and troughs in each minimal period. Our bifurcation argument differs slightly from earlier theory, and under certain conditions we prove that the waves found are different from the ones in previous investigations. An important part of the analysis is a fairly complete description of the small-amplitude solutions. Finally, we investigate the asymptotic behavior of solutions on the local bifurcation set.

  18. REACT: Alternatives to Critical Materials in Magnets

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: The 14 projects that comprise ARPA-E’s REACT Project, short for “Rare Earth Alternatives in Critical Technologies”, are developing cost-effective alternatives to rare earths, the naturally occurring minerals with unique magnetic properties that are used in electric vehicle (EV) motors and wind generators. The REACT projects will identify low-cost and abundant replacement materials for rare earths while encouraging existing technologies to use them more efficiently. These alternatives would facilitate the widespread use of EVs and wind power, drastically reducing the amount of greenhouse gases released into the atmosphere.

  19. Thermoelectric efficiency of critical quantum junctions

    E-Print Network [OSTI]

    Mihail Mintchev; Luca Santoni; Paul Sorba

    2013-10-30

    We derive the efficiency at maximal power of a scale-invariant (critical) quantum junction in exact form. Both Fermi and Bose statistics are considered. We show that time-reversal invariance is spontaneously broken. For fermions we implement a new mechanism for efficiency enhancement above the Curzon-Ahlborn bound, based on a shift of the particle energy in each heat reservoir, proportional to its temperature. In this setting fermionic junctions can even reach at maximal power the Carnot efficiency. The bosonic junctions at maximal power turn out to be less efficient then the fermionic ones.

  20. Critical Nuclear Utilities Upgrade Project (CNUUP) (4572)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent Bonding in Actinide SandwichCray era Craycourse-inventoryCritical

  1. Fuel Cells for Critical Communications Backup Power

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12, 2015ExecutiveFluorescentDanKathy LoftusFuel CellFuel Fuelgreen hfor Critical

  2. A Desktop 3D Printer in Safety-Critical Java

    E-Print Network [OSTI]

    A Desktop 3D Printer in Safety-Critical Java Tórur Biskopstø Strøm Kongens Lyngby 2012 IMM-MSc-2012-critical use cases implemented according to the specification. This thesis presents a RepRap 3D desktop printer

  3. Teaching Against Tradition: Historical Preludes to Critical Pedagogy 

    E-Print Network [OSTI]

    Thomas, Brad 1974-

    2012-09-27

    This dissertation revises the historical narrative of critical pedagogy in college writing classrooms. It argues that the key principles of critical pedagogy, first articulated by Paulo Freire in Pedagogy of the Oppressed, were practiced by a number...

  4. Game worlds : a study of video game criticism

    E-Print Network [OSTI]

    Gursoy, Ayse

    2013-01-01

    This paper explores the relation between criticism and establishment of narrative forms and genres, focusing on the cultural situation of video games. Comparing the context of early film criticism and contemporary video ...

  5. Testing of Critical Features of Polysilicon MEMS

    SciTech Connect (OSTI)

    LAVAN,DAVID A.; BUCHHEIT,THOMAS E.

    1999-12-02

    The behavior of MEMS devices is limited by the strength of critical features such as thin ligaments, oxide cuts joining layers, pin joints and hinges. Devices fabricated at Sandia's Microelectronic Development Laboratory have been successfully tested to investigate these features. A series of measurements were performed on samples with gage lengths of 15 to 1000 microns, using conventional and tungsten coated samples as well as samples that include the critical features of standard components in the test section. Specimens have a freely moving pin joint on one end that anchors the sample to the silicon die to allow rotation to reduce effects of bending. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. Load is calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional losses. The specimen cross section and gage length dimensions were verified by measuring against a standard in the SEM. Multiple tests can be programmed at one time and performed without operator assistance allowing the collection of significant populations of data.

  6. Critical length limiting super-low friction

    E-Print Network [OSTI]

    Ming Ma; Andrea Benassi; Andrea Vanossi; Michael Urbakh

    2015-01-02

    Since the demonstration of super-low friction (superlubricity) in graphite at nanoscale, one of the main challenges in the field of nano- and micro-mechanics was to scale this phenomenon up. A key question to be addressed is to what extent superlubricity could persist, and what mechanisms could lead to its failure. Here, using an edge-driven Frenkel-Kontorova model, we establish a connection between the critical length above which superlubricity disappears and both intrinsic material properties and experimental parameters. A striking boost in dissipated energy with chain length emerges abruptly due to a high-friction stick-slip mechanism caused by deformation of the slider leading to a local commensuration with the substrate lattice. We derived a parameter-free analytical model for the critical length that is in excellent agreement with our numerical simulations. Our results provide a new perspective on friction and nano-manipulation and can serve as a theoretical basis for designing nano-devices with super-low friction, such as carbon nanotubes.

  7. Super critical water oxidation on energetic materials

    SciTech Connect (OSTI)

    Sanchez, J.A.

    1993-01-01

    Supercritical water oxidation (SCWO) is an innovative process for the destruction of hazardous wastes that occurs above the critical temperature and pressure of water. In this paper we present results for the oxidation of simple organic wastes and the destruction of explosives. We have tested a 50 gal./day mobile tubular reactor using both acetone and hexane as surrogate aqueous wastes in reaction with excess oxygen. For acetone, our results indicate that the fuel and oxidant can be conveniently premixed before heating and the acetone effectively destroyed (>99.999%). By contrast, hexane, and likely other insoluble flammable organics must be separately preheated to above the critical temperature of water to avoid detonation. With regards to the treatment of explosives, we have demonstrated detection-sensitivity-limited destruction (typically >99.9%) of five explosives, HMX, RDX, TNT, NQ, and PETN, in a smaller scale SCWO reactor. Two alternative methods of increasing processing throughput for explosives, which have very low solubility in water at room temperature, were also investigated. They are the use of slurries and the SCWO postprocessing of the products of explosives hydrolyzed in low-temperature, basic solutions.

  8. Super critical water oxidation on energetic materials

    SciTech Connect (OSTI)

    Sanchez, J.A.

    1993-04-01

    Supercritical water oxidation (SCWO) is an innovative process for the destruction of hazardous wastes that occurs above the critical temperature and pressure of water. In this paper we present results for the oxidation of simple organic wastes and the destruction of explosives. We have tested a 50 gal./day mobile tubular reactor using both acetone and hexane as surrogate aqueous wastes in reaction with excess oxygen. For acetone, our results indicate that the fuel and oxidant can be conveniently premixed before heating and the acetone effectively destroyed (>99.999%). By contrast, hexane, and likely other insoluble flammable organics must be separately preheated to above the critical temperature of water to avoid detonation. With regards to the treatment of explosives, we have demonstrated detection-sensitivity-limited destruction (typically >99.9%) of five explosives, HMX, RDX, TNT, NQ, and PETN, in a smaller scale SCWO reactor. Two alternative methods of increasing processing throughput for explosives, which have very low solubility in water at room temperature, were also investigated. They are the use of slurries and the SCWO postprocessing of the products of explosives hydrolyzed in low-temperature, basic solutions.

  9. Intelligent Assistants for Filling Critical Gaps in GIS

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Intelligent Assistants for Filling Critical Gaps in GIS A Research Program April 1992 David Lanter, Intelligent Assistants for Filling Critical Gaps In GIS, was sponsored by Southern California Edison Company: · An analysis of critical gaps in current geographic information systems (GIS) that impede their use for spatial

  10. United States Department of Critical Path Method AppliedAgriculture

    E-Print Network [OSTI]

    Forest and Range Experiment Station PO. Box 245, Berkeley, California 94701 August 1986 #12;Critical Path interrelated activities. One approach that has been widely used is the critical path method, in which a network of thousands of activities, such as major construction and engineering projects. In the 1950's, a critical path

  11. Computing Along the Critical Path Dean M. Tullsen Brad Calder

    E-Print Network [OSTI]

    Sair, Suleyman

    Computing Along the Critical Path Dean M. Tullsen Brad Calder Department of Computer Science dependencies that constrain execution speed constitute the critical path of execution. To optimize the performance of the processor, we either have to reduce the critical path or execute it more efficiently

  12. Capturing Post-Silicon Variations using a Representative Critical Path

    E-Print Network [OSTI]

    Sapatnekar, Sachin

    1 Capturing Post-Silicon Variations using a Representative Critical Path Qunzeng Liu and Sachin S on measurements on a replica of the nominal critical path, whose variations are intended to reflect those of the entire circuit after manufacturing. For realistic circuits, where the number of critical paths can

  13. Reconstructing Critical Paths from Execution Traces Martijn Hendriks

    E-Print Network [OSTI]

    Vaandrager, Frits

    Reconstructing Critical Paths from Execution Traces Martijn Hendriks Embedded Systems Institute of constructing critical paths from incomplete information. In general, a directed acyclic graph of tasks with their execution times (i.e., a task graph) is necessary to extract critical paths. We assume, however, that only

  14. Disjoint BoundaryBoundary Paths in Critical Circular Planar Networks

    E-Print Network [OSTI]

    Morrow, James A.

    Disjoint Boundary­Boundary Paths in Critical Circular Planar Networks Ryan Sturgell December 8 that in a critical circular planar network every interior vertex has three disjoint paths to the boundary. 1, 1998 Abstract This paper explores some properties of critical circular planar net­ works. The main

  15. An Efficient Computation of Statistically Critical Sequential Paths Under Retiming

    E-Print Network [OSTI]

    Lim, Sung Kyu

    An Efficient Computation of Statistically Critical Sequential Paths Under Retiming Mongkol the statistically critical paths under retiming, which are the paths with a high probability of becoming timing- critical after retiming. SRTA enables the designers to perform circuit optimization on these paths

  16. Accurate Critical Path Analysis via Random Trace Construction

    E-Print Network [OSTI]

    Zilles, Craig

    Accurate Critical Path Analysis via Random Trace Construction Pierre Salverda Charles Tucker Craig to their profiled behavior. We demonstrate our technique in the context of critical path analysis, showing it can achieve the same accuracy as a hardware critical path predictor, but with lower hardware requirements. Key

  17. Hybrid Statistical Model Checking Technique for Reliable Safety Critical Systems

    E-Print Network [OSTI]

    @cs.kaist.ac.kr Abstract--Reliability of safety critical systems such as nuclear power plants and automobiles has become1 Hybrid Statistical Model Checking Technique for Reliable Safety Critical Systems Youngjoo Kim a significant issue to our society. As more computing systems are utilized in these safety critical systems

  18. Critical Nuclear Charges for N-Electron Atoms

    E-Print Network [OSTI]

    Kais, Sabre

    Critical Nuclear Charges for N-Electron Atoms ALEXEI V. SERGEEV, SABRE KAIS Department of Chemistry is proposed to describe the motion of a loosely bound electron in a multielectron atom when the nuclear charge, which is treated as a continuous parameter, approaches its critical value. The critical nuclear charge

  19. Utility Provider Liability for Electrical Failure: Implications for Interdependent Critical Infrastructure

    SciTech Connect (OSTI)

    Brown, Colleen E.; Chang, Stephanie E.; McDaniels, Timothy L.

    2006-06-15

    As power failures continue to occur and a consistent record of the types of effects experienced by dependent critical infrastructure accumulates, there may be changes in the courts' finding of fact as to what is 'reasonably foreseeable.' If this shift occurs, the minimum standard of care owed by one party to another may be affected and the bar on what constitutes a reasonable level of blackout preparedness and mitigation efforts may be raised. (author)

  20. Non-Abelian Born-Infeld Action and Solitons for Critical Non-BPS Branes

    E-Print Network [OSTI]

    N. D. Lambert; I. Sachs

    2000-08-11

    The non-abelian flat directions in the tachyon potential of stable non-BPS branes recently found are shown to persist to all orders in alpha' at tree level in the string coupling. We also obtain the non-abelian Born-Infeld action including the tachyon potential for a stack of stable non-BPS branes on a critical orbifold. Finally we discuss stable soliton states on the non-BPS brane.

  1. Liquid level detector

    DOE Patents [OSTI]

    Tshishiku, Eugene M. (Augusta, GA)

    2011-08-09

    A liquid level detector for conductive liquids for vertical installation in a tank, the detector having a probe positioned within a sheath and insulated therefrom by a seal so that the tip of the probe extends proximate to but not below the lower end of the sheath, the lower end terminating in a rim that is provided with notches, said lower end being tapered, the taper and notches preventing debris collection and bubble formation, said lower end when contacting liquid as it rises will form an airtight cavity defined by the liquid, the interior sheath wall, and the seal, the compression of air in the cavity preventing liquid from further entry into the sheath and contact with the seal. As a result, the liquid cannot deposit a film to form an electrical bridge across the seal.

  2. Granular impact and the critical packing state

    E-Print Network [OSTI]

    Umbanhowar, Paul; 10.1103/PhysRevE.82.010301

    2010-01-01

    Impact dynamics during collisions of spheres with granular media reveal a pronounced and non-trivial dependence on volume fraction \\phi. Post impact crater morphology identifies the critical packing state \\phi_{cps}, where sheared grains neither dilate nor consolidate, and indicates an associated change in spatial response. Current phenomenological models fail to capture the observed impact force for most \\phi; only near \\phi_{cps} is force separable into additive terms linear in depth and quadratic in velocity. At fixed depth the quadratic drag coefficient decreases (increases) with depth for \\phi \\phi_{cps}). At fixed low velocity, depth dependence of force shows a Janssen-type exponential response with a length scale that decreases with increasing \\phi; and is nearly constant for \\phi > \\phi_{cps}.

  3. Granular impact and the critical packing state

    E-Print Network [OSTI]

    Paul Umbanhowar; Daniel I. Goldman

    2010-07-16

    Impact dynamics during collisions of spheres with granular media reveal a pronounced and non-trivial dependence on volume fraction \\phi. Post impact crater morphology identifies the critical packing state \\phi_{cps}, where sheared grains neither dilate nor consolidate, and indicates an associated change in spatial response. Current phenomenological models fail to capture the observed impact force for most \\phi; only near \\phi_{cps} is force separable into additive terms linear in depth and quadratic in velocity. At fixed depth the quadratic drag coefficient decreases (increases) with depth for \\phi \\phi_{cps}). At fixed low velocity, depth dependence of force shows a Janssen-type exponential response with a length scale that decreases with increasing \\phi; and is nearly constant for \\phi > \\phi_{cps}.

  4. A Review of Criticality Accidents 2000 Revision

    SciTech Connect (OSTI)

    Thomas P. McLaughlin; Shean P. Monahan; Norman L. Pruvost; Vladimir V. Frolov; Boris G. Ryazanov; Victor I. Sviridov

    2000-05-01

    Criticality accidents and the characteristics of prompt power excursions are discussed. Sixty accidental power excursions are reviewed. Sufficient detail is provided to enable the reader to understand the physical situation, the chemistry and material flow, and when available the administrative setting leading up to the time of the accident. Information on the power history, energy release, consequences, and causes are also included when available. For those accidents that occurred in process plants, two new sections have been included in this revision. The first is an analysis and summary of the physical and neutronic features of the chain reacting systems. The second is a compilation of observations and lessons learned. Excursions associated with large power reactors are not included in this report.

  5. Geometrically induced magnetic catalysis and critical dimensions

    E-Print Network [OSTI]

    Antonino Flachi; Kenji Fukushima; Vincenzo Vitagliano

    2015-04-27

    We discuss the combined effect of magnetic fields and geometry in interacting fermionic systems. At leading order in the heat-kernel expansion, the infrared singularity (that in flat space leads to the magnetic catalysis) is regulated by the chiral gap effect, and the catalysis is deactivated by the effect of the scalar curvature. We discover that an infrared singularity is found in higher-order terms that mix the magnetic field with curvature, and these lead to a novel form of geometrically induced magnetic catalysis. The dynamical mass squared is then modified not only due to the chiral gap effect by an amount proportional to the curvature, but also by a magnetic shift $\\propto (4-D)eB$, where $D$ represents the number of space-time dimensions. We argue that $D=4$ is a critical dimension across which the behavior of the magnetic shift changes qualitatively.

  6. Draft low level waste technical summary

    SciTech Connect (OSTI)

    Powell, W.J.; Benar, C.J.; Certa, P.J.; Eiholzer, C.R.; Kruger, A.A.; Norman, E.C.; Mitchell, D.E.; Penwell, D.E.; Reidel, S.P.; Shade, J.W.

    1995-09-01

    The purpose of this document is to present an outline of the Hanford Site Low-Level Waste (LLW) disposal program, what it has accomplished, what is being done, and where the program is headed. This document may be used to provide background information to personnel new to the LLW management/disposal field and to those individuals needing more information or background on an area in LLW for which they are not familiar. This document should be appropriate for outside groups that may want to learn about the program without immediately becoming immersed in the details. This document is not a program or systems engineering baseline report, and personnel should refer to more current baseline documentation for critical information.

  7. National Criticality Experiments Research Center: Capability and Status

    SciTech Connect (OSTI)

    Hayes, David K. [Los Alamos National Laboratory; Myers, William L. [Los Alamos National Laboratory

    2012-07-12

    After seven years, the former Los Alamos Critical Experiments Facility (LACEF), or Pajarito Site, has reopened for business as the National Criticality Experiments Research Center (NCERC) at the Nevada National Security Site (NNSS). Four critical assembly machines (Comet, Planet, Flat-Top, and Godiva-IV) made the journey from Los Alamos to the NNSS. All four machines received safety system upgrades along with new digital control systems. Between these machines, systems ranging from the thermal through the intermediate to the fast spectrum may be assembled. Steady-State, transient, and super-prompt critical conditions may be explored. NCERC is the sole remaining facility in the United States capable of conducting general-purpose nuclear materials handling including the construction and operation of high-multiplication assemblies, delayed critical assemblies, and prompt critical assemblies. Reconstitution of the unique capabilities at NCERC ensures the viability of (1) The Nuclear Renaissance, (2) Stockpile Stewardship, and (3) and the next generation of criticality experimentalists.

  8. Quantum chaos and critical behavior on a chip

    E-Print Network [OSTI]

    Neill Lambert; Yueh-nan Chen; Robert Johannsson; Franco Nori

    2009-05-29

    The Dicke model describes N qubits (or two-level atoms) homogenously coupled to a bosonic mode. Here we examine an open-system realization of the Dicke model, which contains critical and chaotic behaviour. In particular, we extend this model to include an additional open transport qubit (TQ) (coupled to the bosonic mode) for passive and active measurements. We illustrate how the scaling (in the number of qubits N) of the superradiant phase transition can be observed in both current and current-noise measurements through the transport qubit. Using a master equation, we also investigate how the phase transition is affected by the back-action from the transport qubit and losses in the cavity. In addition, we show that the non-integrable quantum chaotic character of the Dicke model is retained in an open-system environment. We propose how all of these effects could been seen in a circuit QED system formed from an array of superconducting qubits, or an atom chip, coupled to a quantized resonant cavity (e.g., a microwave transmission line).

  9. Breckinridge Project, initial effort. Report XI, Volume V. Critical review of the design basis. [Critical review

    SciTech Connect (OSTI)

    1982-01-01

    Report XI, Technical Audit, is a compendium of research material used during the Initial Effort in making engineering comparisons and decisions. Volumes 4 and 5 of Report XI present those studies which provide a Critical Review of the Design Basis. The Critical Review Report, prepared by Intercontinental Econergy Associates, Inc., summarizes findings from an extensive review of the data base for the H-Coal process design. Volume 4 presents this review and assessment, and includes supporting material; specifically, Design Data Tabulation (Appendix A), Process Flow Sheets (Appendix B), and References (Appendix C). Volume 5 is a continuation of the references of Appendix C. Studies of a proprietary nature are noted and referenced, but are not included in these volumes. They are included in the Limited Access versions of these reports and may be reviewed by properly cleared personnel in the offices of Ashland Synthetic Fuels, Inc.

  10. Breckinridge Project, initial effort. Report XI, Volume IV. Critical review of the design basis. [Critical review

    SciTech Connect (OSTI)

    none,

    1981-05-01

    Report XI, Technical Audit, is a compendium of research material used during the Initial Effort in making engineering comparisons and decisions. Volumes 4 and 5 of Report XI present those studies which provide a Critical Review of the Design Basis. The Critical Review Report, prepared by Intercontinental Econergy Associates, Inc., summarizes findings from an extensive review of the data base for the H-Coal process design. Volume 4 presents this review and assessment, and includes supporting material; specifically, Design Data Tabulation (Appendix A), Process Flow Sheets (Appendix B), and References (Appendix C). Volume 5 is a continuation of the references of Appendix C. Studies of a proprietary nature are noted and referenced, but are not included in these volumes. They are included in the Limited Access versions of these reports and may be reviewed by properly cleared personnel in the offices of Ashland Synthetic Fuels, Inc.

  11. UNIVERSITY OF CALIFORNIA, SAN DIEGO Critical-Path Aware Processor Architectures

    E-Print Network [OSTI]

    Sair, Suleyman

    UNIVERSITY OF CALIFORNIA, SAN DIEGO Critical-Path Aware Processor Architectures A dissertation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 C. Multithreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 III Critical Path Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 A. General Critical-Path Analysis

  12. Critical Dynamics in the Early Universe

    E-Print Network [OSTI]

    B. L. Hu

    1993-02-22

    Methods and concepts for the study of phase transitions mediated by a time-dependent order-parameter field in curved spacetimes are discussed. A practical example is the derivation of an effective (quasi-)potential for the description of `slow-roll' inflation in the early universe. We first summarize our early results on viewing the symmetry behavior of constant background fields in curved but static spacetimes as finite size effect, and the use of derivative expansions for constructing effective actions for slowly-varying background fields. We then introduce the notion of dynamical finite size effect to explain how an exponential expansion of the scale factor imparts a finite size to the system and how the symmetry behavior in de Sitter space can be understood qualitatively in this light. We reason why the exponential inflation can be described equivalently by a scale transformation, thus rendering this special class of dynamics as effectively static. Finally we show how, in this view, one can treat the class of `slow-roll' inflation as a dynamic perturbation off the effectively static class of exponential inflation and understand it as a dynamical critical phenomenon in cosmology.

  13. Perturbative Critical Behavior from Spacetime Dependent Couplings

    SciTech Connect (OSTI)

    Dong, Xi; Horn, Bart; Silverstein, Eva; Torroba, Gonzalo

    2012-08-03

    We find novel perturbative fixed points by introducing mildly spacetime-dependent couplings into otherwise marginal terms. In four-dimensional QFT, these are physical analogues of the small-{epsilon} Wilson-Fisher fixed point. Rather than considering 4-{epsilon} dimensions, we stay in four dimensions but introduce couplings whose leading spacetime dependence is of the form {lambda}x{sup {kappa}}{mu}{sup {kappa}}, with a small parameter {kappa} playing a role analogous to {epsilon}. We show, in {phi}{sup 4} theory and in QED and QCD with massless flavors, that this leads to a critical theory under perturbative control over an exponentially wide window of spacetime positions x. The exact fixed point coupling {lambda}{sub *}(x) in our theory is identical to the running coupling of the translationally invariant theory, with the scale replaced by 1/x. Similar statements hold for three-dimensional {phi}{sup 6} theories and two-dimensional sigma models with curved target spaces. We also describe strongly coupled examples using conformal perturbation theory.

  14. Critical infrastructure systems of systems assessment methodology.

    SciTech Connect (OSTI)

    Sholander, Peter E.; Darby, John L.; Phelan, James M.; Smith, Bryan; Wyss, Gregory Dane; Walter, Andrew; Varnado, G. Bruce; Depoy, Jennifer Mae

    2006-10-01

    Assessing the risk of malevolent attacks against large-scale critical infrastructures requires modifications to existing methodologies that separately consider physical security and cyber security. This research has developed a risk assessment methodology that explicitly accounts for both physical and cyber security, while preserving the traditional security paradigm of detect, delay, and respond. This methodology also accounts for the condition that a facility may be able to recover from or mitigate the impact of a successful attack before serious consequences occur. The methodology uses evidence-based techniques (which are a generalization of probability theory) to evaluate the security posture of the cyber protection systems. Cyber threats are compared against cyber security posture using a category-based approach nested within a path-based analysis to determine the most vulnerable cyber attack path. The methodology summarizes the impact of a blended cyber/physical adversary attack in a conditional risk estimate where the consequence term is scaled by a ''willingness to pay'' avoidance approach.

  15. Fronts and fluctuations at a critical surface

    E-Print Network [OSTI]

    Haim Weissmann; Nadav M. Shnerb; David A. Kessler

    2015-08-14

    The properties of a front between two different phases in the presence of a smoothly inhomogeneous external field that takes its critical value at the crossing point is analyzed. Two generic scenarios are studied. In the first, the system admits a bistable solution and the external field governs the rate in which one phase invades the other. The second mechanism corresponds to a second order transition that, in the case of reactive systems, takes the form of a transcritical bifurcation at the crossing point. We solve for the front shape and its response to external white noise, showing that static properties and also some of the dynamics features cannot distinguish between the two scenarios. The only reliable indicator turns out to be the fluctuation statistics. These take a Gaussian form in the bifurcation case and a double-peak shape in a bistable system. The results of a recent analysis of the morphogenesis process in Drosophila embryos are reanalyzed and we show, in contrast with the interpretation suggested by Krotov et. al., that the plausible underlying dynamics is bistable and not bifurcational.

  16. Critical behaviour for scalar nonlinear waves

    E-Print Network [OSTI]

    Davide Masoero; Andrea Raimondo; Pedro R. S. Antunes

    2015-02-06

    In the long-wave regime, nonlinear waves may undergo a phase transition from a smooth to a fast oscillatory behaviour. We study this phenomenon, commonly known as dispersive shock, in the light of Dubrovin's universality conjecture , and we argue that the transition can be described by a special solution of a model universal partial differential equation. This universal solution is constructed by means of a string equation. We provide a classification of universality classes and the explicit description of the transition by means of special functions, extending Dubrovin's universality conjecture to a wider class of equations. In particular, we show that Benjamin-Ono equation belongs to a novel universality class with respect to the ones known in the literature, and we compute its string equation exactly. We describe our results using the language of statistical mechanics, showing that dispersive shocks share many features of the tri-critical point in statistical systems, and building a dictionary between nonlinear waves and statistical mechanics.

  17. Thermal fluctuations and critical behavior in a magnetized, anisotropic plasma

    SciTech Connect (OSTI)

    Hazeltine, R. D.; Mahajan, S. M. [Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)] [Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)

    2013-12-15

    Thermal fluctuations in a magnetized, anisotropic plasma are studied by applying standard methods, based on the Einstein rule, to the known thermodynamic potential of the system. It is found in particular that magnetic fluctuations become critical when the anisotropy p{sub ?}?p{sub ?} changes sign. By examining the critical region, additional insight on the equations of state for near-critical anisotropic plasma is obtained.

  18. Technical/Support Job Level Technical/Support Level I Technical/Support Level II Technical/Support Level III

    E-Print Network [OSTI]

    Technical/Support Job Level Technical/Support Level I Technical/Support Level II Technical supervision Problem Solving Refers to procedures, technical aids, co-workers, or supervisors to solve routine are varied and non-routine Uses knowledge of standardized rules, procedures, and operations to resolve

  19. Critical Materials and Rare Futures: Ames Laboratory Signs a...

    Office of Environmental Management (EM)

    will update its analysis to include the use of critical materials in petroleum refineries and other applications not addressed in last year's report. Other steps are also...

  20. Review of Nevada Site Office Criticality Safety Assessments at the Criticality Experiments Facility and Training Assembly for Criticality Safety and Appraisal of the Criticality Experiments Facility Startup Plan, October 2011

    Broader source: Energy.gov [DOE]

    This report provides the results of an independent oversight review of criticality safety assessment activities conducted by the Department of Energy's (DOE) Nevada Site Office

  1. Energy: Critical Infrastructure and Key Resources Sector-Specific...

    Office of Environmental Management (EM)

    of the National Infrastructure Protection Plan (NIPP) Base Plan, a comprehensive risk management framework that defines critical infrastructure protection (CIP) roles and...

  2. Criticality Safety Evaluation of Hanford Tank Farms Facility

    SciTech Connect (OSTI)

    WEISS, E.V.

    2000-12-15

    Data and calculations from previous criticality safety evaluations and analyses were used to evaluate criticality safety for the entire Tank Farms facility to support the continued waste storage mission. This criticality safety evaluation concludes that a criticality accident at the Tank Farms facility is an incredible event due to the existing form (chemistry) and distribution (neutron absorbers) of tank waste. Limits and controls for receipt of waste from other facilities and maintenance of tank waste condition are set forth to maintain the margin subcriticality in tank waste.

  3. Identifying and Overcoming Critical Barriers to Widespread Second...

    Office of Scientific and Technical Information (OSTI)

    Overcoming Critical Barriers to Widespread Second Use of PEV Batteries Neubauer, J.; Smith, K.; Wood, E.; Pesaran, A. 25 ENERGY STORAGE; 29 ENERGY PLANNING, POLICY AND ECONOMY...

  4. Critical Question #2: What are the Best Practices for Ventilation...

    Energy Savers [EERE]

    2: What are the Best Practices for Ventilation Specific to Multifamily Buildings? Critical Question 2: What are the Best Practices for Ventilation Specific to Multifamily...

  5. Approaches for Developing Uniform Hazard Spectra at Critical...

    Office of Environmental Management (EM)

    Hazard Spectra at Critical Facilities Preliminary Assessment of the Impact of 2014 Seismic Study on WTP Design Evaluation of the SRS Seismic Hazard Considering the EPRI 2013...

  6. Criticality Safety Controls Implementation, May 31, 2013 (HSS...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    representative lines of inquiry to assess criticality control implementation as an integral part of the review of the core functions and implementation of integrated safety...

  7. NNSA Completes its Critical Radar Arming and Fuzing Test for...

    National Nuclear Security Administration (NNSA)

    its Critical Radar Arming and Fuzing Test for the W88 ALT 370 | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile...

  8. Critical Materials Institute signs new member United Technologies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    signs new member United Technologies Research Center Contacts: For release: Aug. 18, 2015 Alex King, Director, Critical Materials Institute, (515) 296-4505 Laura Millsaps, Ames...

  9. Reducing Cyber Risk to Critical Infrastructure: NIST Framework...

    Office of Environmental Management (EM)

    Order (EO) 13636 "Improving Critical Infrastructure Cybersecurity" of February 2013 directed the National Institute of Standards and Technology (NIST) to work with...

  10. Critical Performance and Durability Parameters of an Integrated...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Durability Parameters of an Integrated Aftertreatment System used to Meet Tier II Emission Standards Critical Performance and Durability Parameters of an Integrated...

  11. Critical Decision 4 (CD-4) Approval Template | Department of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    More Documents & Publications Example BCP Template Critical Decision 2 (CD-2) Approval Template SOW and Key Performance Parameters (KPP) Handbook Final Version 9-30-2014...

  12. EV Everywhere Workshop: Electric Motors and Critical Materials...

    Broader source: Energy.gov (indexed) [DOE]

    EV Everywhere Workshop: Power Electronics and Thermal Management Breakout Session Report Electric Motors and Critical Materials EV Everywhere - Charge to Breakout Sessions...

  13. Security Risk Assessment Methodologies (RAM) for Critical Infrastructu...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Building Energy Efficiency Find More Like This Return to Search Security Risk Assessment Methodologies (RAM) for Critical Infrastructures Sandia National Laboratories...

  14. Critical review of water based radiant cooling system design methods

    E-Print Network [OSTI]

    Feng, Jingjuan Dove; Bauman, Fred; Schiavon, Stefano

    2014-01-01

    buildings CRITICAL REVIEW OF WATER BASED RADIANT COOLINGare two primary types of water-based radiant systems: (1)cooling/heating output, water supply temperatures Notes NA

  15. Transmission and Display of Information for TimeCritical Decisions

    E-Print Network [OSTI]

    Horvitz, Eric

    and the cost of delaying tranmission of the data in time­critical contexts. We show how the methods apply also

  16. A Web-Based Nuclear Criticality Safety Bibliographic Database

    SciTech Connect (OSTI)

    Koponen, B L; Huang, S

    2007-02-22

    A bibliographic criticality safety database of over 13,000 records is available on the Internet as part of the U.S. Department of Energy's (DOE) Nuclear Criticality Safety Program (NCSP) website. This database is easy to access via the Internet and gets substantial daily usage. This database and other criticality safety resources are available at ncsp.llnl.gov. The web database has evolved from more than thirty years of effort at Lawrence Livermore National Laboratory (LLNL), beginning with compilations of critical experiment reports and American Nuclear Society Transactions.

  17. Critical Factors Driving the High Volumetric Uptake of Methane...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Critical Factors Driving the High Volumetric Uptake of Methane in Cu-3(btc)(2) Previous Next List Hulvey, Zeric; Vlaisavljevich, Bess; Mason, Jarad A.; Tsivion, Ehud; Dougherty,...

  18. Specified assurance level sampling procedure

    SciTech Connect (OSTI)

    Willner, O.

    1980-11-01

    In the nuclear industry design specifications for certain quality characteristics require that the final product be inspected by a sampling plan which can demonstrate product conformance to stated assurance levels. The Specified Assurance Level (SAL) Sampling Procedure has been developed to permit the direct selection of attribute sampling plans which can meet commonly used assurance levels. The SAL procedure contains sampling plans which yield the minimum sample size at stated assurance levels. The SAL procedure also provides sampling plans with acceptance numbers ranging from 0 to 10, thus, making available to the user a wide choice of plans all designed to comply with a stated assurance level.

  19. Ongoing work of scholars of the critical childhood collaborative 

    E-Print Network [OSTI]

    Stough, Laura

    2009-01-01

    stream_source_info Ongoing work of scholars of the critical childhood collaborative.pdf.txt stream_content_type text/plain stream_size 4 Content-Encoding ISO-8859-1 stream_name Ongoing work of scholars of the critical childhood...

  20. Safety Lifecycle for Developing Safety Critical Artificial Neural Networks

    E-Print Network [OSTI]

    Kelly, Tim

    Safety Lifecycle for Developing Safety Critical Artificial Neural Networks Zeshan Kurd, Tim Kelly.kelly}@cs.york.ac.uk Abstract. Artificial neural networks are employed in many areas of industry such as medicine and defence. There are many techniques that aim to improve the performance of neural networks for safety-critical systems

  1. CRITICAL REVIEW OF BIOLOGY AND CONTROL OF OYSTER DRILLS

    E-Print Network [OSTI]

    CRITICAL REVIEW OF BIOLOGY AND CONTROL OF OYSTER DRILLS Urosalpinx and Eupleura Marine Biological L, Farley, Director Critical Review of Biology and Control of Oyster Drills UROSALPINX and EUPLEURA 17 General 17 Nervous System 20 Circulatory System 20 Locomotory System 21 Drilling and Feeding

  2. Proceedings of the Nuclear Criticality Technology and Safety Project Workshop

    SciTech Connect (OSTI)

    Sanchez, R.G. [comp.

    1994-01-01

    This report is the proceedings of the annual Nuclear Criticality Technology and Safety Project (NCTSP) Workshop held in Monterey, California, on April 16--28, 1993. The NCTSP was sponsored by the Department of Energy and organized by the Los Alamos Critical Experiments Facility. The report is divided into six sections reflecting the sessions outlined on the workshop agenda.

  3. Critical behavior in inhomogeneous random graphs Remco van der Hofstad

    E-Print Network [OSTI]

    Hofstad, Remco van der

    Critical behavior in inhomogeneous random graphs Remco van der Hofstad June 10, 2010 Abstract We study the critical behavior of inhomogeneous random graphs where edges are present independently but with unequal edge occupation probabilities. The edge probabilities are moderated by vertex weights

  4. WIPP-025, Rev. 0 Summary of Nuclear Criticality Safety

    E-Print Network [OSTI]

    WIPP-025, Rev. 0 Summary of Nuclear Criticality Safety Evaluation for Shielded Containers AT THE WASTE ISOLATION PILOT PLANT WIPP-025, REV. 0 AUGUST 2009 This document revision was prepared PLANT WIPP-025, REV. 0 AUGUST 2009 Summary of Nuclear Criticality Safety Evaluation for Shielded

  5. COMMUNITY CURRENCIES AND SOCIAL INCLUSION: A CRITICAL EVALUATION

    E-Print Network [OSTI]

    Bateman, Ian J.

    COMMUNITY CURRENCIES AND SOCIAL INCLUSION: A CRITICAL EVALUATION by Gill Seyfang CSERGE Working Paper EDM 05-09 #12;COMMUNITY CURRENCIES AND SOCIAL INCLUSION: A CRITICAL EVALUATION By Gill Seyfang Centre for Social and Economic Research on the Global Environment, School of Environmental Sciences

  6. Random matrix theory and critical phenomena in quantum spin chains

    E-Print Network [OSTI]

    J. Hutchinson; J. P. Keating; F. Mezzadri

    2015-03-19

    We compute critical properties of a general class of quantum spin chains which are quadratic in the Fermi operators and can be solved exactly under certain symmetry constraints related to the classical compact groups $U(N)$, $O(N)$ and $Sp(2N)$. In particular we calculate critical exponents $s$, $\

  7. Scattering for radial, semi-linear, super-critical wave equations with bounded critical norm

    E-Print Network [OSTI]

    Benjamin Dodson; Andrew Lawrie

    2014-09-04

    In this paper we study the focusing cubic wave equation in 1+5 dimensions with radial initial data as well as the one-equivariant wave maps equation in 1+3 dimensions with the model target manifolds $\\mathbb{S}^3$ and $\\mathbb{H}^3$. In both cases the scaling for the equation leaves the $\\dot{H}^{\\frac{3}{2}} \\times \\dot{H}^{\\frac{1}{2}}$-norm of the solution invariant, which means that the equation is super-critical with respect to the conserved energy. Here we prove a conditional scattering result: If the critical norm of the solution stays bounded on its maximal time of existence, then the solution is global in time and scatters to free waves both forwards and backwards in infinite time. The methods in this paper also apply to all supercritical power-type nonlinearities for both the focusing and defocusing radial semi-linear equation in 1+5 dimensions, yielding analogous results.

  8. Interior Light Level Measurements Appendix F -Interior Light Level Measurements

    E-Print Network [OSTI]

    Appendix F ­ Interior Light Level Measurements #12;F.1 Appendix F - Interior Light Level. A potential concern is that a lower VT glazing may increase electric lighting use to compensate for lost qualify and quantify a representative loss of daylighting, and therefore electric lighting use

  9. Critical technologies for reactors used in nuclear electric propulsion

    SciTech Connect (OSTI)

    Bhattacharyya, S.K. (Argonne National Lab., IL (United States))

    1993-01-01

    Nuclear electric Propulsion (NEP) systems are expected to play a significant role in the exploration and exploitation of space. Unlike nuclear thermal propulsion (NTP) systems in which the hot reactor coolant is directly discharged from nozzles to provide the required thrust, NEP systems include electric power generation and conditioning units that in turn are used to drive electric thrusters. These thrusters accelerate sub atomic particles to produce thrust. The major advantage of NEP systems is the ability to provide very high specific impulses ([approximately]5000 s) that minimize the requirement for propellants. In addition, the power systems used in NEP could pro vide the dual purpose of also providing power for the missions at the destination. This synergism can be exploited in shared development costs. The NEP systems produce significantly lower thrust that NTP systems and are generally more massive. Both systems have their appropriate roles in a balanced space program. The technology development needs of NEP systems differ in many important ways from the development needs for NTP systems because of the significant differences in the operating conditions of the systems. The NEP systems require long-life reactor power systems operating at power levels that are considerably lower than those for NTP systems. In contrast, the operational lifetime of an NEP system (years) is orders of magnitude longer than the operational lifetime of NTP systems (thousands of second). Thus, the critical issue of NEP is survivability and reliable operability for very long times at temperatures that are considerably more modest than the temperatures required for effective NTP operations but generally much higher than those experienced in terrestrial reactors.

  10. Simon Holland 1 Artificial Intelligence in music education: a critical review Artificial Intelligence in music education: a critical review

    E-Print Network [OSTI]

    Holland, Simon

    © Simon Holland 1 Artificial Intelligence in music education: a critical review Artificial Intelligence in Music Education: a critical review. In Miranda, E. (ed.) Readings in Music and Artificial This paper reviews the principal approaches to using Artificial Intelligence in Music Education. Music

  11. Use of a Web Site to Enhance Criticality Safety Training

    SciTech Connect (OSTI)

    Huang, S T; Morman, J

    2003-08-04

    Currently, a website dedicated to enhancing communication and dissemination of criticality safety information is sponsored by the U.S. Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP). This website was developed as part of the DOE response to the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 97-2, which reflected the need to make criticality safety information available to a wide audience. The website is the focal point for DOE nuclear criticality safety (NCS) activities, resources and references, including hyperlinks to other sites actively involved in the collection and dissemination of criticality safety information. The website is maintained by the Lawrence Livermore National Laboratory (LLNL) under auspices of the NCSP management. One area of the website contains a series of Nuclear Criticality Safety Engineer Training (NCSET) modules. During the past few years, many users worldwide have accessed the NCSET section of the NCSP website and have downloaded the training modules as an aid for their training programs. This trend was remarkable in that it points out a continuing need of the criticality safety community across the globe. It has long been recognized that training of criticality safety professionals is a continuing process involving both knowledge-based training and experience-based operations floor training. As more of the experienced criticality safety professionals reach retirement age, the opportunities for mentoring programs are reduced. It is essential that some method be provided to assist the training of young criticality safety professionals to replenish this limited human expert resource to support on-going and future nuclear operations. The main objective of this paper is to present the features of the NCSP website, including its mission, contents, and most importantly its use for the dissemination of training modules to the criticality safety community. We will discuss lessons learned and several ideas for future development in the area of web-based training for criticality safety professionals. Our effort is intended to stimulate a discussion of ideas and solicit participation in the development of the next generation of a web-based criticality training site that can be used to assist the training of newcomers to this important safety discipline.

  12. ACCELERATED TESTING OF NEUTRON-ABSORBING ALLOYS FOR NUCLEAR CRITICALITY CONTROL

    SciTech Connect (OSTI)

    Ronald E. Mizia

    2011-10-01

    The US Department of Energy requires nuclear criticality control materials be used for storage of highly enriched spent nuclear fuel used in government programs and the storage of commercial spent nuclear fuel at the proposed High-Level Nuclear Waste Geological Repository located at Yucca Mountain, Nevada. Two different metallic alloys (Ni-Cr-Mo-Gd and borated stainless steel) have been chosen for this service. An accelerated corrosion test program to validate these materials for this application is described and a performance comparison is made.

  13. Service Level Agreement/Specification

    E-Print Network [OSTI]

    Flynn, E. Victor

    Service Level Agreement/Specification For Maintenance and Associated Risk Management Services Team c. Contract Labour 4. REACTIVE MAINTENANCE 5. ESTATE DATA REQUIREMENTS 6. ESTATE EMERGENCY. RISK MANAGEMENT a. General b. Scope of Service c. Statement of Intent Service Level Agreement 2007 Vers

  14. ALIGNMENT, LEVELING AND DEPLOYMENT CONSTRAINTS

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Thermoelectric Generator (RTG) Crew Deployment Description Passive Seismic Experiment (PSE) Crew Deployment Description Leveling and Alignment Solar Wind Spectrometer (SWS) Crew Deployment Description Leveling to deplo~nent. Design of ALSEP allows deployment when sun angle is from 5 to 45 degrees. 2 #12;CENTRAL

  15. TRIPOLI-4 criticality calculations for MOX fuelled SNEAK 7A and 7B fast critical assemblies

    SciTech Connect (OSTI)

    Lee, Y. K. [Commissariat a l'Energie Atomique et aux Energies Alternatives, CEA-Saclay, DEN/DANS/DM2S/SERMA, 91191 Gif sur Yvette Cedex (France)

    2012-07-01

    A prototype Generation IV fast neutron reactor is under design and development in France. The MOX fuel will be introduced into this self-generating core in order to demonstrate low net plutonium production. To support the TRIPOLI-4 Monte Carlo transport code in criticality calculations of fast reactors, the effective delayed neutron fraction {beta}eff estimation and the Probability Tables (PT) option to treat the unresolved resonance region of cross-sections are two essentials. In this study, TRIPOLI-4 calculations have been made using current nuclear data libraries JEFF-3.1.1 and ENDF/B-VII.0 to benchmark the reactor physics parameters of the MOX fuelled SNEAK 7A and 7B fast critical assemblies. TRIPOLI-4 calculated K{sub eff} and {beta}eff of the homogeneous R-Z models and the 3D multi-cell models have been validated against the measured ones. The impact of the PT option on K{sub eff} is 340 {+-} 10 pcm for SNEAK 7A core and 410 {+-} 12 pcm for 7B. Four-group spectra and energy spectral indices, f8/f5, f9/f5, and c8/f5 in the two SNEAK cores have also been calculated with the TRIPOLI-4 mesh tally. Calculated spectrum-hardening index f8/f5 is 0.0418 for SNEAK 7A and 0.0315 for 7B. From this study the SNEAK 3D models have been verified for the next revision of IRPhE (International Handbook of Evaluated Reactor Physics Benchmark Experiments). (authors)

  16. Critical speed measurements in the Tevatron cold compressors

    SciTech Connect (OSTI)

    DeGraff, B.; Bossert, R.; Martinez, A.; Soyars, W.M.; /Fermilab

    2006-01-01

    The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high energy operations. Nominal operating range for these compressors is 43,000 to 85,000 rpm. Past foil bearing failures prompted investigation to determine if critical speeds for operating compressors fall within operating range. Data acquisition hardware and software settings will be discussed for measuring liftoff, first critical and second critical speeds. Several tests provided comparisons between an optical displacement probe and accelerometer measurements. Vibration data and analysis of the 20 Tevatron ring cold compressors will be presented.

  17. Universality of critical magnetic field in holographic superconductor

    E-Print Network [OSTI]

    D. Momeni; R. Myrzakulov

    2015-02-11

    In this letter we study aspects of the holographic superconductors analytically in the presence of a constant external magnetic field. We show that the critical temperature and critical magnetic field can be calculated at nonzero temperature. We detect the Meissner effect in such superconductors. A universal relation between black hole mass $ M$ and critical magnetic field $H_c$ is proposed as $\\frac{H_c}{M^{2/3}}\\leq 0.687365$. We discuss some aspects of phase transition in terms of black hole entropy and the Bekenstein's entropy to energy upper bound.

  18. Additional nuclear criticality safety calculations for small-diameter containers

    SciTech Connect (OSTI)

    Hone, M.J.

    1996-01-01

    This report documents additional criticality safety analysis calculations for small diameter containers, which were originally documented in Reference 1. The results in Reference 1 indicated that some of the small diameter containers did not meet the criteria established for criticality safety at the Portsmouth facility (K{sub eff} +2{sigma}<.95) when modeled under various contingency assumptions of reflection and moderation. The calculations performed in this report reexamine those cases which did not meet the criticality safety criteria. In some cases, unnecessary conservatism is removed, and in other cases mass or assay limits are established for use with the respective containers.

  19. Scaling and universality of multipartite entanglement at criticality

    E-Print Network [OSTI]

    Alonso Botero; Benni Reznik

    2007-10-01

    Using the geometric entanglement measure, we study the scaling of multipartite entanglement in several 1D models at criticality, specifically the linear harmonic chain and the XY spin chain encompassing both the Ising and XX critical models. Our results provide convincing evidence that 1D models at criticality exhibit a universal logarithmic scaling behavior ~(c/12)log l in the multipartite entanglement per region for a partition of the system into regions of size l, where c is the central charge of the corresponding universality class in conformal field theory.

  20. Criticality Safety Basics for INL FMHs and CSOs

    SciTech Connect (OSTI)

    V. L. Putman

    2012-04-01

    Nuclear power is a valuable and efficient energy alternative in our energy-intensive society. However, material that can generate nuclear power has properties that require this material be handled with caution. If improperly handled, a criticality accident could result, which could severely harm workers. This document is a modular self-study guide about Criticality Safety Principles. This guide's purpose it to help you work safely in areas where fissionable nuclear materials may be present, avoiding the severe radiological and programmatic impacts of a criticality accident. It is designed to stress the fundamental physical concepts behind criticality controls and the importance of criticality safety when handling fissionable materials outside nuclear reactors. This study guide was developed for fissionable-material-handler and criticality-safety-officer candidates to use with related web-based course 00INL189, BEA Criticality Safety Principles, and to help prepare for the course exams. These individuals must understand basic information presented here. This guide may also be useful to other Idaho National Laboratory personnel who must know criticality safety basics to perform their assignments safely or to design critically safe equipment or operations. This guide also includes additional information that will not be included in 00INL189 tests. The additional information is in appendices and paragraphs with headings that begin with 'Did you know,' or with, 'Been there Done that'. Fissionable-material-handler and criticality-safety-officer candidates may review additional information at their own discretion. This guide is revised as needed to reflect program changes, user requests, and better information. Issued in 2006, Revision 0 established the basic text and integrated various programs from former contractors. Revision 1 incorporates operation and program changes implemented since 2006. It also incorporates suggestions, clarifications, and additional information from readers and from personnel who took course 00INL189. Revision 1 also completely reorganized the training to better emphasize physical concepts behind the criticality controls that fissionable material handlers and criticality safety officers must understand. The reorganization is based on and consistent with changes made to course 00INL189 due to a review of course exam results and to discussions with personnel who conduct area-specific training.

  1. Burst wait time simulation of CALIBAN reactor at delayed super-critical state

    SciTech Connect (OSTI)

    Humbert, P.; Authier, N.; Richard, B.; Grivot, P.; Casoli, P.

    2012-07-01

    In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present the point model deterministic method used to calculate the probability distribution of the wait time before a prescribed count level taking into account prompt neutrons and delayed neutron precursors. This method is based on the solution of the time dependent adjoint Kolmogorov master equations for the number of detections using the generating function methodology [8,9,10] and inverse discrete Fourier transforms. The obtained results are then compared to the measurements and Monte-Carlo calculations based on the algorithm presented in [7]. (authors)

  2. Geometry-dependent critical currents in superconducting nanocircuits

    E-Print Network [OSTI]

    Clem, John R.

    In this paper, we calculate the critical currents in thin superconducting strips with sharp right-angle turns, 180? turnarounds, and more complicated geometries, where all the line widths are much smaller than the Pearl ...

  3. Model of critical heat flux in subcooled flow boiling

    E-Print Network [OSTI]

    Fiori, Mario P.

    1968-01-01

    The physical phenomenon occurring before and at the critical heat flux (CHF) for subcooled flow boiling has been investigated. The first phase of this study established the basic nature of the flow structure at CHF. A ...

  4. Jefferson Lab News - Jefferson Lab Achieves Critical Milestone...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Achieves Critical Milestone Toward Construction of 310-Million Upgrade Project Pion This architectural rendering shows the Hall D complex to be built as part of the CEBAF 12 GeV...

  5. Transport signatures of quantum critically in Cr at high pressure.

    SciTech Connect (OSTI)

    Jaramillo, R.; Feng, Y.; Wang, J.; Rosenbaum, T. F.

    2010-08-03

    The elemental antiferromagnet Cr at high pressure presents a new type of naked quantum critical point that is free of disorder and symmetry-breaking fields. Here we measure magnetotransport in fine detail around the critical pressure, P{sub c} {approx} 10 GPa, in a diamond anvil cell and reveal the role of quantum critical fluctuations at the phase transition. As the magnetism disappears and T {yields} 0, the magntotransport scaling converges to a non-mean-field form that illustrates the reconstruction of the magnetic Fermi surface, and is distinct from the critical scaling measured in chemically disordered Cr:V under pressure. The breakdown of itinerant antiferromagnetism only comes clearly into view in the clean limit, establishing disorder as a relevant variable at a quantum phase transition.

  6. Bazaar [+] : addressing critical adjacencies in Mumbai's urban farm

    E-Print Network [OSTI]

    Bhat, Arjun (Arjun Devadas)

    2008-01-01

    This thesis focuses on the city of Mumbai, and evolves the notion of how "critical adjacency" has been instrumental in guiding the city's urban transformations into modernity. Presently, Mumbai experiences some of the ...

  7. Critical Review of Desalination Concentrate Management, Treatment and Beneficial Use

    E-Print Network [OSTI]

    University, Las Cruces, New Mexico. 3 Department of Civil & Environmental Engineering, Colorado School for deep well injection, land availability), costs, and potential environmental impacts. Converting and environmental impacts. This paper critically reviews con- centrate management strategies, treatment technologies

  8. Alarm guided critical function and success path monitoring

    DOE Patents [OSTI]

    Scarola, Kenneth (Windsor, CT); Jamison, David S. (Windsor, CT); Manazir, Richard M. (North Canton, CT); Rescorl, Robert L. (Vernon, CT); Harmon, Daryl L. (Enfield, CT)

    1994-01-01

    The use of alarm indication on the overview (IPSO) display to initiate diagnosis of challenges to critical functions or unavailability of success paths, and further alarm-based guidance toward ultimate diagnosis.

  9. Thermodynamic and transport property modeling in super critical water

    E-Print Network [OSTI]

    Kutney, Michael C. (Michael Charles)

    2005-01-01

    Supercritical water oxidation (SCWO) is a thermally-based, remediation and waste-treatment process that relies on unique property changes of water when water is heated and pressurized above its critical point. Above its ...

  10. PNNL Results from 2009 Silene Criticality Accident Dosimeter Intercomparison Exercise

    SciTech Connect (OSTI)

    Hill, Robin L.; Conrady, Matthew M.

    2010-06-30

    This document reports the results of testing of the Hanford Personnel Nuclear Accident Dosimeter (PNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on October 13, 14, and 15, 2009.

  11. Critical heat flux maxima during boiling crisis on textured surfaces

    E-Print Network [OSTI]

    Dhillon, Navdeep Singh

    Enhancing the critical heat flux (CHF) of industrial boilers by surface texturing can lead to substantial energy savings and global reduction in greenhouse gas emissions, but fundamentally this phenomenon is not well ...

  12. On the universal critical behavior in 3-flavor QCD

    E-Print Network [OSTI]

    Dominik Smith; Christian Schmidt

    2011-09-30

    We analyze the universal critical behavior at the chiral critical point in QCD with three degenerate quark masses. We confirm that this critical point lies in the universality class of the three dimensional Ising model. The symmetry of the Ising model, which is Z(2), is not directly realized in the QCD Hamiltonian. After making an ansatz for the magnetization- and energy-like operators as linear admixtures of the chiral condensate and the gluonic action, we determine several non-universal mixing and normalization constants. These parameters determine an unambiguous mapping of the critical behavior in QCD to that of the 3d-Ising model. We verify its validity by showing that the thus obtained orderparameter scales in accordance with the magnetic equation of state of the 3d-Ising model.

  13. Identification of critical locations across multiple infrastructures for terrorist actions

    E-Print Network [OSTI]

    Patterson, Sean A. (Sean Albert), 1981-

    2005-01-01

    This paper discusses a possible approach to ranking geographic regions that can influence multiple infrastructures. Once ranked, decision makers can determine whether these regions are critical locations based on their ...

  14. State Policies Provide Critical Support for Renewable Electricity

    E-Print Network [OSTI]

    Barbose, Galen

    2009-01-01

    types of state policies have been critical to the growth of renewable energy,types of state policies for supporting electricity generation from geothermal and other forms of renewable energy:

  15. MECHANICAL ENGINEERING AN OVERVIEW OF THE CRITICAL ISSUES IN INTEGRATED

    E-Print Network [OSTI]

    Fisher, Frank

    introduces the critical packaging issues and challenges facing the semiconductor industry in selecting, IC Packaging Handbooks, co-edited a McGraw Hill book titled "Failure-Free IC Packages", conducted

  16. EERE Announces Up to $4 Million for Critical Materials Recovery...

    Energy Savers [EERE]

    mining projects. The United States imports many critical materials we need to expand our clean energy economy. Some of them may be found in the fluids produced by geothermal power...

  17. Bulk Entanglement Spectrum Reveals Quantum Criticality within a Topological State

    E-Print Network [OSTI]

    Fu, Liang

    A quantum phase transition is usually achieved by tuning physical parameters in a Hamiltonian at zero temperature. Here, we show that the ground state of a topological phase itself encodes critical properties of its ...

  18. Critically Evaluated Thermochemical Properties of Polycyclic Aromatic Hydrocarbons

    E-Print Network [OSTI]

    Chickos, James S.

    values for these thermochemical properties and for the enthalpies of formation in the gas state at T=298Critically Evaluated Thermochemical Properties of Polycyclic Aromatic Hydrocarbons María Victoria Experimental thermochemical properties of benzene, toluene, and 63 polycyclic aro- matic hydrocarbons

  19. State Policies Provide Critical Support for Renewable Electricity

    E-Print Network [OSTI]

    Barbose, Galen

    2009-01-01

    it can compete against other renewable resource options.Critical Support for Renewable Electricity Galen Barbose,July 15, 2008 Growth in renewable energy in the U.S. over

  20. Determination of pool boiling Critical Heat Flux enhancement in nanofluids

    E-Print Network [OSTI]

    Truong, Bao H. (Bao Hoai)

    2007-01-01

    Nanofluids are engineered colloids composed of nano-size particles dispersed in common fluids such as water or refrigerants. Using an electrically controlled wire heater, pool boiling Critical Heat Flux (CHF) of Alumina ...

  1. Applicability of reactor code WIMS for nuclear criticality safety studies

    SciTech Connect (OSTI)

    Matausek, M.V.; Marinkovic, N.

    1995-12-31

    The purpose of this paper is to examine applicability of the reactor code WIMS for calculating criticality parameters of nonreactor configurations containing fissile materials. Results are given and discussed for some typical configurations containing {sup 235}U.

  2. The critical temperature of superconductor and its electronic specific heat

    E-Print Network [OSTI]

    B. V. Vasiliev

    2010-08-09

    It is shown that the critical temperature of the superconductor is related to the Sommerfeld constant, i.e. it is determined by the Fermi energy for I-type superconductors. The estimation of properties of II-type superconductors reveals a somewhat different relation of critical temperature and Fermi energy. Among the high-temperature superconducting ceramics there are the both - I and II - types superconductors.

  3. Low temperature upper critical eld studies in organic superconductor

    E-Print Network [OSTI]

    Zuo, Fulin

    Low temperature upper critical eld studies in organic superconductor 00 -BEDT-TTF2SF5CH2CF2SO3 F 00-BEDT-TTF2SF5CH2CF2SO3: For eld parallel to the superconducting layers, the upper critical eldCH2CF2SO3 at low temperatures and eld up to 18 Tesla. For eld parallel to the planes, the upper

  4. Balancing of high speed, flexible rotating shafts across critical speeds 

    E-Print Network [OSTI]

    White, Gary Paul

    1977-01-01

    BALANCING OF HIGH SPEED, FLEXIBLE ROTATING SHAFTS ACROSS CRITICAL SPEEDS A Thesis by Gary Paul White Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1977 Major Subject: Mechanical Engineering Gary Paul White 1977 BALANCING OF HIGH SPEED, FLEXIBLE ROTATING SHAFTS ACROSS CRITICAL SPEEDS A Thesis by GARY PAUL WHITE Approved as to style and content by: Head of Department Member August...

  5. Simulations of liquid ribidium expanded to the critical density

    SciTech Connect (OSTI)

    Ross, M; Yang, L H; Pilgrim, W

    2006-05-16

    Quantum molecular dynamic simulations were used to examine the change in atomic and electronic structure in liquid rubidium along its liquid-vapor coexistence curve. Starting from the liquid at the triple point, with increasing expansion we observe a continuous increase in the electron localization leading to ion clustering near the metal-nonmetal transition at about twice the critical density, in agreement with electrical measurements, and to the presence of dimers near and below the critical density.

  6. Numerical Simulations of Leakage from Underground LPG Storage Caverns

    E-Print Network [OSTI]

    Yamamoto, Hajime; Pruess, Karsten

    2004-01-01

    2.5.6. Saturated vapor pressure of propane Ideal Gas Heatpropane viscosity as a function of temperature, at P = 1.013x10 5 Pa Wagner Equation Saturated Vapor Pressure,pressure suitable for propane is about 0.8 MPa, slightly exceeding the saturated vapor

  7. Study identifies two Northwest basalt rock caverns sites for...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Well data was plugged into PNNL's STOMP computer model, which simulates the movement of fluids below ground, to determine how much air the various sites under consideration could...

  8. Number of Existing Natural Gas Salt Caverns Storage Fields

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet)DecadeYear Jan Feb MarthroughFeet)Feet) YearThousand81Nuclear >35 37

  9. EIA - Natural Gas Pipeline Network - Salt Cavern Storage Reservoir

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming963 1.969

  10. Research Library Service Level Agreement

    E-Print Network [OSTI]

    Wechsler, Risa H.

    Research Library Service Level Agreement 2015-2016 Contents THE SLAC RESEARCH LIBRARY PURPOSE.................................................................................................3 DESCRIPTION OF SLAC RESEARCH LIBRARY COLLECTIONS AND SERVICES......4 Electronic Resources Access.......................................................................................9 APPENDIX: SLAC RESEARCH LIBRARY RULES...................................................10 #12

  11. Low Level Heat Recovery Technology 

    E-Print Network [OSTI]

    O'Brien, W. J.

    1982-01-01

    With today's high fuel prices, energy conservation projects to utilize low level waste heat have become more attractive. Exxon Chemical Company Central Engineering has been developing guidelines and assessing the potential for application of low...

  12. Low-Level Waste Requirements

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1999-07-09

    The guide provides criteria for determining which DOE radioactive wastes are to be managed as low-level waste in accordance with DOE M 435.1-1, Chapter IV.

  13. High-Level Waste Requirements

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1999-07-09

    The guide provides the criteria for determining which DOE radioactive wastes are to be managed as high-level waste in accordance with DOE M 435.1-1.

  14. Experience With the SCALE Criticality Safety Cross Section Libraries

    SciTech Connect (OSTI)

    Bowman, S.M.

    2000-08-21

    This report provides detailed information on the SCALE criticality safety cross-section libraries. Areas covered include the origins of the libraries, the data on which they are based, how they were generated, past experience and validations, and performance comparisons with measured critical experiments and numerical benchmarks. The performance of the SCALE criticality safety cross-section libraries on various types of fissile systems are examined in detail. Most of the performance areas are demonstrated by examining the performance of the libraries vs critical experiments to show general trends and weaknesses. In areas where directly applicable critical experiments do not exist, performance is examined based on the general knowledge of the strengths and weaknesses of the cross sections. In this case, the experience in the use of the cross sections and comparisons with the results of other libraries on the same systems are relied on for establishing acceptability of application of a particular SCALE library to a particular fissile system. This report should aid in establishing when a SCALE cross-section library would be expected to perform acceptably and where there are known or suspected deficiencies that would cause the calculations to be less reliable. To determine the acceptability of a library for a particular application, the calculational bias of the library should be established by directly applicable critical experiments.

  15. Criticality safety analysis on fissile materials in Fukushima reactor cores

    SciTech Connect (OSTI)

    Liu, Xudong; Lemaitre-Xavier, E.; Ahn, Joonhong [Department of Nuclear Engineering, University of California, Berkeley, Berkeley, CA 94720 (United States); Hirano, Fumio [Japan Atomic Energy Agency, Geological Isolation Research and Development Directorate, Tokai-mura, Ibaraki 319-1194 (Japan)

    2013-07-01

    The present study focuses on the criticality analysis for geological disposal of damaged fuels from Fukushima reactor cores. Starting from the basic understanding of behaviors of plutonium and uranium, a scenario sequence for criticality event is considered. Due to the different mobility of plutonium and uranium in geological formations, the criticality safety is considered in two parts: (1) near-field plutonium system and (2) far-field low enriched uranium (LEU) system. For the near-field plutonium system, a mathematical analysis for pure-solute transport was given, assuming a particular buffer material and waste form configuration. With the transport and decay of plutonium accounted, the critical mass of plutonium was compared with the initial load of a single canister. Our calculation leads us to the conclusion that our system with the initial loading being the average mass of plutonium in an assembly just before the accident is very unlikely to become critical over time. For the far-field LEU system, due to the uncertainties in the geological and geochemical conditions, calculations were made in a parametric space that covers the variation of material compositions and different geometries. Results show that the LEU system could not remain sub-critical within the entire parameter space assumed, although in the iron-rich rock, the neutron multiplicity is significantly reduced.

  16. Criticality Safety Code Validation with LWBR’s SB Cores

    SciTech Connect (OSTI)

    Putman, Valerie Lee

    2003-01-01

    The first set of critical experiments from the Shippingport Light Water Breeder Reactor Program included eight, simple geometry critical cores built with 233UO2-ZrO2, 235UO2-ZrO2, ThO2, and ThO2-233UO2 nuclear materials. These cores are evaluated, described, and modeled to provide benchmarks and validation information for INEEL criticality safety calculation methodology. In addition to consistency with INEEL methodology, benchmark development and nuclear data are consistent with International Criticality Safety Benchmark Evaluation Project methodology.Section 1 of this report introduces the experiments and the reason they are useful for validating some INEEL criticality safety calculations. Section 2 provides detailed experiment descriptions based on currently available experiment reports. Section 3 identifies criticality safety validation requirement sources and summarizes requirements that most affect this report. Section 4 identifies relevant hand calculation and computer code calculation methodologies used in the experiment evaluation, benchmark development, and validation calculations. Section 5 provides a detailed experiment evaluation. This section identifies resolutions for currently unavailable and discrepant information. Section 5 also reports calculated experiment uncertainty effects. Section 6 describes the developed benchmarks. Section 6 includes calculated sensitivities to various benchmark features and parameters. Section 7 summarizes validation results. Appendices describe various assumptions and their bases, list experimenter calculations results for items that were independently calculated for this validation work, report other information gathered and developed by SCIENTEC personnel while evaluating these same experiments, and list benchmark sample input and miscellaneous supplementary data.

  17. An implicit level set method for modeling hydraulically driven fractures Anthony Peirce a,*, Emmanuel Detournay b

    E-Print Network [OSTI]

    Peirce, Anthony

    An implicit level set method for modeling hydraulically driven fractures Anthony Peirce a the relevant tip asymptotics in hydraulic fracture simulators is critical for the accuracy and stability for a propagating hydraulic fracture. A number of char- acteristics of the governing equations for hydraulic

  18. Determining the Criticality of Processes in Kahn Process Networks for Design Space Exploration

    E-Print Network [OSTI]

    on the critical path must have a criticality of 1 since none of them can be slowed down without increasing the length of the critical path. As another example, a process which is executed in parallel with a process on the critical path can be slowed down by a factor equal to the execution time of the process on the critical

  19. Modeling and simulation technology readiness levels.

    SciTech Connect (OSTI)

    Clay, Robert L.; Shneider, Max S.; Marburger, S. J.; Trucano, Timothy Guy

    2006-01-01

    This report summarizes the results of an effort to establish a framework for assigning and communicating technology readiness levels (TRLs) for the modeling and simulation (ModSim) capabilities at Sandia National Laboratories. This effort was undertaken as a special assignment for the Weapon Simulation and Computing (WSC) program office led by Art Hale, and lasted from January to September 2006. This report summarizes the results, conclusions, and recommendations, and is intended to help guide the program office in their decisions about the future direction of this work. The work was broken out into several distinct phases, starting with establishing the scope and definition of the assignment. These are characterized in a set of key assertions provided in the body of this report. Fundamentally, the assignment involved establishing an intellectual framework for TRL assignments to Sandia's modeling and simulation capabilities, including the development and testing of a process to conduct the assignments. To that end, we proposed a methodology for both assigning and understanding the TRLs, and outlined some of the restrictions that need to be placed on this process and the expected use of the result. One of the first assumptions we overturned was the notion of a ''static'' TRL--rather we concluded that problem context was essential in any TRL assignment, and that leads to dynamic results (i.e., a ModSim tool's readiness level depends on how it is used, and by whom). While we leveraged the classic TRL results from NASA, DoD, and Sandia's NW program, we came up with a substantially revised version of the TRL definitions, maintaining consistency with the classic level definitions and the Predictive Capability Maturity Model (PCMM) approach. In fact, we substantially leveraged the foundation the PCMM team provided, and augmented that as needed. Given the modeling and simulation TRL definitions and our proposed assignment methodology, we conducted four ''field trials'' to examine how this would work in practice. The results varied substantially, but did indicate that establishing the capability dependencies and making the TRL assignments was manageable and not particularly time consuming. The key differences arose in perceptions of how this information might be used, and what value it would have (opinions ranged from negative to positive value). The use cases and field trial results are included in this report. Taken together, the results suggest that we can make reasonably reliable TRL assignments, but that using those without the context of the information that led to those results (i.e., examining the measures suggested by the PCMM table, and extended for ModSim TRL purposes) produces an oversimplified result--that is, you cannot really boil things down to just a scalar value without losing critical information.

  20. High critical currents in heavily doped (Gd,Y)Ba2Cu3Ox superconductor tapes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Selvamanickam, V.; Gharahcheshmeh, M. Heydari; Xu, A.; Galstyan, E.; Delgado, L.; Cantoni, C.

    2015-01-20

    REBa2Cu3Ox superconductor tapes with moderate levels of dopants have been optimized for high critical current density in low magnetic fields at 77 K, but they do not exhibit exemplary performance in conditions of interest for practical applications, i.e., temperatures less than 50 K and fields of 2–30 T. Heavy doping of REBCO tapes has been avoided by researchers thus far due to deterioration in properties. Here, we report achievement of critical current densities (Jc) above 20 MA/cm2 at 30 K, 3 T in heavily doped (25 mol. % Zr-added) (Gd,Y)Ba2Cu3Ox superconductor tapes, which is more than three times higher thanmore »the Jc typically obtained in moderately doped tapes. Pinning force levels above 1000 GN/m3 have also been attained at 20 K. A composition map of lift factor in Jc (ratio of Jc at 30 K, 3 T to the Jc at 77 K, 0 T) has been developed which reveals the optimum film composition to obtain lift factors above six, which is thrice the typical value. A highly c-axis aligned BaZrO3 (BZO) nanocolumn defect density of nearly 7 × 1011 cm–2 as well as 2–3nm sized particles rich in Cu and Zr have been found in the high Jc films.« less

  1. FLUX SENSOR EVALUATIONS AT THE ATR CRITICAL FACILITY

    SciTech Connect (OSTI)

    Troy Unruh; Joy Rempe; David Nigg; George Imel; Jason Harris; Eric Bonebrake

    2010-11-01

    The Advanced Test Reactor (ATR) and the ATR Critical (ATRC) facilities lack real-time methods for detecting thermal neutron flux and fission reaction rates for irradiation capsules. Direct measurements of the actual power deposited into a test are now possible without resorting to complicated correction factors. In addition, it is possible to directly measure minor actinide fission reaction rates and to provide time-dependent monitoring of the fission reaction rate or fast/thermal flux during transient testing. A joint Idaho State University /Idaho National Laboratory ATR National Scientific User Facility (ATR NSUF) project was recently initiated to evaluate new real-time state-of-the-art in-pile flux detection sensors. Initially, the project is comparing the accuracy, response time, and long duration performance of French Atomic Energy Commission (CEA)-developed miniature fission chambers, specialized self-powered neutron detectors (SPNDs) by the Argentinean National Energy Commission (CNEA), specially developed commercial SPNDs, and back-to-back fission (BTB) chambers developed by Argonne National Laboratory (ANL). As discussed in this paper, specialized fixturing and software was developed by INL to facilitate these joint ISU/INL evaluations. Calculations were performed by ISU to assess the performance of and reduce uncertainties in flux detection sensors and compare data obtained from these sensors with existing integral methods employed at the ATRC. Ultimately, project results will be used to select the detector that can provide the best online regional ATRC power measurement. It is anticipated that project results may offer the potential to increase the ATRC’s current power limit and its ability to perform low-level irradiation experiments. In addition, results from this effort will provide insights about the viability of using these detectors in the ATR. Hence, this effort complements current activities to improve ATR software tools, computational protocols and in-core instrumentation under the ATR Modeling, Simulation and V&V Upgrade initiative, as well as the work to replace nuclear instrumentation under the ATR Life Extension Project (LEP) and provide support to the ATR NSUF.

  2. Technology Readiness Levels for Advanced Nuclear Fuels and Materials Development

    SciTech Connect (OSTI)

    Jon Carmack

    2014-01-01

    The Technology Readiness Level (TRL) process is used to quantitatively assess the maturity of a given technology. The TRL process has been developed and successfully used by the Department of Defense (DOD) for development and deployment of new technology and systems for defense applications. In addition, NASA has also successfully used the TRL process to develop and deploy new systems for space applications. Advanced nuclear fuels and materials development is a critical technology needed for closing the nuclear fuel cycle. Because the deployment of a new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the TRL concept to the advanced fuel development program is very useful as a management and tracking tool. This report provides definition of the technology readiness level assessment process as defined for use in assessing nuclear fuel technology development for the Advanced Fuel Campaign (AFC).

  3. State Policies Provide Critical Support for Renewable Electricity

    SciTech Connect (OSTI)

    Barbose, Galen; Wiser, Ryan; Bolinger, Mark

    2008-07-15

    Growth in renewable energy in the U.S. over the past decade has been propelled by a number of forces, including rising fossil fuel prices, environmental concerns, and policy support at the state and federal levels. In this article, we review and discuss what are arguably the two most important types of state policies for supporting electricity generation from geothermal and other forms of renewable energy: renewables portfolio standards and utility integrated resource planning requirements. Within the Western U.S., where the vast majority of the nation's readily-accessible geothermal resource potential resides, these two types of state policies have been critical to the growth of renewable energy, and both promise to continue to play a fundamental role for the foreseeable future. In its essence, a renewables portfolio standard (RPS) requires utilities and other retail electricity suppliers to produce or purchase a minimum quantity or percentage of their generation supply from renewable resources. RPS purchase obligations generally increase over time, and retail suppliers typically must demonstrate compliance on an annual basis. Mandatory RPS policies are backed by various types of compliance enforcement mechanisms, although most states have incorporated some type of cost-containment provision, such as a cost cap or a cap on retail rate impacts, which could conceivably allow utilities to avoid (full) compliance with their RPS target. Currently, 27 states and the District of Columbia have mandatory RPS requirements. Within the eleven states of the contiguous Western U.S., all but three (Idaho, Utah, and Wyoming) now have a mandatory RPS legislation (Utah has a more-voluntary renewable energy goal), covering almost 80% of retail electricity sales in the region. Although many of these state policies have only recently been established, their impact is already evident: almost 1800 MW of new renewable capacity has been installed in Western states following the implementation of RPS policies. To date, wind energy has been the primary beneficiary of state RPS policies, representing approximately 83% of RPS-driven renewable capacity growth in the West through 2007. Geothermal energy occupies a distant second place, providing 7% of RPS-driven new renewable capacity in the West since the late 1990s, though geothermal's contribution on an energy (MWh) basis is higher. Looking to the future, a sizable quantity of renewable capacity beyond pre-RPS levels will be needed to meet state RPS mandates: about 25,000 MW by 2025 within the Western U.S. Geothermal energy is beginning to provide an increasingly significant contribution, as evidenced by the spate of new projects recently announced to meet state RPS requirements. Most of this activity has been driven by the RPS policies in California and Nevada, where the Geothermal Energy Association has identified 47 new geothermal projects, totaling more than 2,100 MW, in various stages of development. Additional geothermal projects in Arizona, New Mexico, Oregon, and Washington are also under development to meet those states RPS requirements. The other major state policy driver for renewable electricity growth, particularly in the West, is integrated resource planning (IRP). IRP was first formalized as a practice in the 1980s, but the practice was suspended in some states as electricity restructuring efforts began. A renewed interest in IRP has emerged in the past several years, however, with several Western states (California, Montana, and New Mexico) reestablishing IRP and others developing new rules to strengthen their existing processes. In its barest form, IRP simply requires that utilities periodically submit long-term resource procurement plans in which they evaluate alternative strategies for meeting their resource needs over the following ten to twenty years. However, many states have developed specific requirements for the IRP process that directly or indirectly support renewable energy. The most general of these is an explicit requirement that utilities evaluate renewables, and that

  4. Level indicator for pressure vessels

    DOE Patents [OSTI]

    Not Available

    1982-04-28

    A liquid-level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic-field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal-processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  5. High pressure liquid level monitor

    DOE Patents [OSTI]

    Bean, Vern E. (Frederick, MD); Long, Frederick G. (Ijamsville, MD)

    1984-01-01

    A liquid level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  6. Comments on Critical Electric and Magnetic Fields from Holography

    E-Print Network [OSTI]

    S. Bolognesi; F. Kiefer; E. Rabinovici

    2013-01-29

    We discuss some aspects of critical electric and magnetic fields in a field theory with holographic dual description. We extend the analysis of arxiv:1109.2920, which finds a critical electric field at which the Schwinger pair production barrier drops to zero, to the case of magnetic fields. We first find that, unlike ordinary weakly coupled theories, the magnetic field is not subject to any perturbative instability originating from the presence of a tachyonic ground state in the W-boson spectrum. This follows from the large value of the 't Hooft coupling \\lambda, which prevents the Zeeman interaction term to overcome the particle mass at high B. Consequently, we study the next possible B-field instability, i.e. monopole pair production, which is the S-dual version of the Schwinger effect. Also in this case a critical magnetic field is expected when the tunneling barrier drops to zero. These Schwinger-type criticalities are the holographic duals, in the bulk, to the fields E or B reaching the tension of F1 or D1 strings respectively. We then discuss how this effect is modified when electric and magnetic fields are present simultaneously and dyonic states in the spectrum can be pair produced by a generic E - B background. Finally, we analyze finite temperature effects on Schwinger criticalities, i.e. in the AdS-Schwarzshild black hole background.

  7. Nambu-Goldstone Effective Theory of Information at Quantum Criticality

    E-Print Network [OSTI]

    Gia Dvali; Andre Franca; Cesar Gomez; Nico Wintergerst

    2015-07-10

    We establish a fundamental connection between quantum criticality of a many-body system, such as Bose-Einstein condensates, and its capacity of information-storage and processing. For deriving the effective theory of modes in the vicinity of the quantum critical point we develop a new method by mapping a Bose-Einstein condensate of $N$-particles onto a sigma model with a continuous global (pseudo)symmetry that mixes bosons of different momenta. The Bogolyubov modes of the condensate are mapped onto the Goldstone modes of the sigma model, which become gapless at the critical point. These gapless Goldstone modes are the quantum carriers of information and entropy. Analyzing their effective theory, we observe the information-processing properties strikingly similar to the ones predicted by the black hole portrait. The energy cost per qubit of information-storage vanishes in the large-$N$ limit and the total information-storage capacity increases with $N$ either exponentially or as a power law. The longevity of information-storage also increases with $N$, whereas the scrambling time in the over-critical regime is controlled by the Lyapunov exponent and scales logarithmically with $N$. This connection reveals that the origin of black hole information storage lies in the quantum criticality of the graviton Bose-gas, and that much simpler systems that can be manufactured in table-top experiments can exhibit very similar information-processing dynamics.

  8. SIGNAL-PATH LEVEL ASSIGNMENT FOR DUAL-Vt TECHNIQUE

    E-Print Network [OSTI]

    Wang, Yu

    be assigned to some of the transistors in the non-critical paths and a lower Vt is assigned to other to get the critical paths and non-critical paths of the circuit much faster and with more accuracy. The gates in the critical paths will remain unchanged to maintain the performance; and the gates in the non-critical

  9. Timing Analysis & Optimization for Multi-Level Networks

    E-Print Network [OSTI]

    Kalla, Priyank

    , slack @ k = +ve slack, -ve slack Topologically longest path ­ "timing critical", hence critical path A Critical Paths ­ True critical paths (on which signal propagates) ­ Optimize true critical paths, don't want to optimize a path w/ less delay and ignore one w/ larger delay ­ Don't want to identify FALSE

  10. Critical experiments at Sandia National Laboratories : technical meeting on low-power critical facilities and small reactors.

    SciTech Connect (OSTI)

    Harms, Gary A.; Ford, John T.; Barber, Allison Delo

    2010-11-01

    Sandia National Laboratories (SNL) has conducted radiation effects testing for the Department of Energy (DOE) and other contractors supporting the DOE since the 1960's. Over this period, the research reactor facilities at Sandia have had a primary mission to provide appropriate nuclear radiation environments for radiation testing and qualification of electronic components and other devices. The current generation of reactors includes the Annular Core Research Reactor (ACRR), a water-moderated pool-type reactor, fueled by elements constructed from UO2-BeO ceramic fuel pellets, and the Sandia Pulse Reactor III (SPR-III), a bare metal fast burst reactor utilizing a uranium-molybdenum alloy fuel. The SPR-III is currently defueled. The SPR Facility (SPRF) has hosted a series of critical experiments. A purpose-built critical experiment was first operated at the SPRF in the late 1980's. This experiment, called the Space Nuclear Thermal Propulsion Critical Experiment (CX), was designed to explore the reactor physics of a nuclear thermal rocket motor. This experiment was fueled with highly-enriched uranium carbide fuel in annular water-moderated fuel elements. The experiment program was completed and the fuel for the experiment was moved off-site. A second critical experiment, the Burnup Credit Critical Experiment (BUCCX) was operated at Sandia in 2002. The critical assembly for this experiment was based on the assembly used in the CX modified to accommodate low-enriched pin-type fuel in water moderator. This experiment was designed as a platform in which the reactivity effects of specific fission product poisons could be measured. Experiments were carried out on rhodium, an important fission product poison. The fuel and assembly hardware for the BUCCX remains at Sandia and is available for future experimentation. The critical experiment currently in operation at the SPRF is the Seven Percent Critical Experiment (7uPCX). This experiment is designed to provide benchmark reactor physics data to support validation of the reactor physics codes used to design commercial reactor fuel elements in an enrichment range above the current 5% enrichment cap. A first set of critical experiments in the 7uPCX has been completed. More experiments are planned in the 7uPCX series. The critical experiments at Sandia National Laboratories are currently funded by the US Department of Energy Nuclear Criticality Safety Program (NCSP). The NCSP has committed to maintain the critical experiment capability at Sandia and to support the development of a critical experiments training course at the facility. The training course is intended to provide hands-on experiment experience for the training of new and re-training of practicing Nuclear Criticality Safety Engineers. The current plans are for the development of the course to continue through the first part of fiscal year 2011 with the development culminating is the delivery of a prototype of the course in the latter part of the fiscal year. The course will be available in fiscal year 2012.

  11. ECE Teaching Staff, Level 4,

    E-Print Network [OSTI]

    Hickman, Mark

    ECE Teaching Staff, Level 4, Von Haast Building ECE Labs Electrical & Computer Engineering #12;ELEC Electronics Lab & Randy Hampton Control Lab Machines Lab & Ken Smart Mech. Workshop & Dave Healy Power Building Student Workshop The Shed Café Kim Rutter 441 & Philipp Hof Yonghe Liu Seminar Room 457 Von Haast

  12. Combined Heat and Power. Enabling Resilient Energy Infrastructure for Critical Facilities

    SciTech Connect (OSTI)

    Hampson, Anne; Bourgeois, Tom; Dillingham, Gavin; Panzarella, Isaac

    2013-03-01

    This report provides context for combined heat and power (CHP) in critical infrastructure applications, as well as case studies and policies promoting CHP in critical infrastructure.

  13. Leadership in Energy and Environmental Design (LEED) - A critical evaluation by LCA and recommendations for improvement

    E-Print Network [OSTI]

    Humbert, Sebastien; Abeck, Heike; Bali, Nishil; Horvath, Arpad

    2007-01-01

    and Environmental Design (LEED): A critical evaluation byand Environmental Design (LEED) A critical evaluation by LCAGoal, Scope and Background. LEED (Leadership in Energy and

  14. Sharp critical behavior for pinning model in random correlated environment

    E-Print Network [OSTI]

    Quentin Berger; Hubert Lacoin

    2011-04-26

    This article investigates the effect for random pinning models of long range power-law decaying correlations in the environment. For a particular type of environment based on a renewal construction, we are able to sharply describe the phase transition from the delocalized phase to the localized one, giving the critical exponent for the (quenched) free-energy, and proving that at the critical point the trajectories are fully delocalized. These results contrast with what happens both for the pure model (i.e. without disorder) and for the widely studied case of i.i.d. disorder, where the relevance or irrelevance of disorder on the critical properties is decided via the so-called Harris Criterion.

  15. Western Wind Strategy: Addressing Critical Issues for Wind Deployment

    SciTech Connect (OSTI)

    Douglas Larson; Thomas Carr

    2012-03-30

    The goal of the Western Wind Strategy project was to help remove critical barriers to wind development in the Western Interconnection. The four stated objectives of this project were to: (1) identify the barriers, particularly barriers to the operational integration of renewables and barriers identified by load-serving entities (LSEs) that will be buying wind generation, (2) communicate the barriers to state officials, (3) create a collaborative process to address those barriers with the Western states, utilities and the renewable industry, and (4) provide a role model for other regions. The project has been on the forefront of identifying and informing state policy makers and utility regulators of critical issues related to wind energy and the integration of variable generation. The project has been a critical component in the efforts of states to push forward important reforms and innovations that will enable states to meet their renewable energy goals and lower the cost to consumers of integrating variable generation.

  16. Gas-liquid critical point in ionic fluids

    E-Print Network [OSTI]

    O. Patsahan; I. Mryglod; T. Patsahan

    2006-06-27

    Based on the method of collective variables we develop the statistical field theory for the study of a simple charge-asymmetric $1:z$ primitive model (SPM). It is shown that the well-known approximations for the free energy, in particular DHLL and ORPA, can be obtained within the framework of this theory. In order to study the gas-liquid critical point of SPM we propose the method for the calculation of chemical potential conjugate to the total number density which allows us to take into account the higher order fluctuation effects. As a result, the gas-liquid phase diagrams are calculated for $z=2-4$. The results demonstrate the qualitative agreement with MC simulation data: critical temperature decreases when $z$ increases and critical density increases rapidly with $z$.

  17. Salt-induced changes of colloidal interactions in critical mixtures

    E-Print Network [OSTI]

    Ursula Nellen; Julian Dietrich; Laurent Helden; Shirish Chodankar; Kim Nygard; J. Friso van der Veen; Clemens Bechinger

    2011-04-28

    We report on salt-dependent interaction potentials of a single charged particle suspended in a binary liquid mixture above a charged wall. For symmetric boundary conditions (BC) we observe attractive particle-wall interaction forces which are similar to critical Casimir forces previously observed in salt-free mixtures. However, in case of antisymmetric BC we find a temperature-dependent crossover from attractive to repulsive forces which is in strong contrast to salt-free conditions. Additionally performed small-angle x-ray scattering experiments demonstrate that the bulk critical fluctuations are not affected by the addition of salt. This suggests that the observed crossover can not be attributed alone to critical Casimir forces. Instead our experiments point towards a possible coupling between the ionic distributions and the concentration profiles in the binary mixture which then affects the interaction potentials in such systems.

  18. Quantum Critical Behaviour in a Graphene-like Model

    E-Print Network [OSTI]

    Simon Hands; Costas Strouthos

    2008-06-30

    We present the first results of numerical simulations of a 2+1 dimensional fermion field theory based on a recent proposal for a model of graphene, consisting of N_f four-component Dirac fermions moving in the plane and interacting via an instantaneous Coulomb interaction. In the strong-coupling limit we identify a critical number of flavors N_fc=4.8(2) separating an insulating from a conducting phase. This transition corresponds to the location of a quantum critical point, and we use a fit to the equation of state for the chiral order parameter to estimate the critical exponents. Next we simulate N_f=2 corresponding to real graphene, and approximately locate a transition from strong to weak coupling behaviour. Strong correlations are evident in the weak-coupling regime.

  19. Critical illumination condenser for x-ray lithography

    DOE Patents [OSTI]

    Cohen, S.J.; Seppala, L.G.

    1998-04-07

    A critical illumination condenser system is disclosed, particularly adapted for use in extreme ultraviolet (EUV) projection lithography based on a ring field imaging system and a laser produced plasma source. The system uses three spherical mirrors and is capable of illuminating the extent of the mask plane by scanning either the primary mirror or the laser plasma source. The angles of radiation incident upon each mirror of the critical illumination condenser vary by less than eight (8) degrees. For example, the imaging system in which the critical illumination condenser is utilized has a 200 {micro}m source and requires a magnification of 26. The three spherical mirror system constitutes a two mirror inverse Cassegrain, or Schwarzschild configuration, with a 25% area obstruction (50% linear obstruction). The third mirror provides the final pupil and image relay. The mirrors include a multilayer reflective coating which is reflective over a narrow bandwidth. 6 figs.

  20. Critical illumination condenser for x-ray lithography

    DOE Patents [OSTI]

    Cohen, Simon J. (Pleasanton, CA); Seppala, Lynn G. (Livermore, CA)

    1998-01-01

    A critical illumination condenser system, particularly adapted for use in extreme ultraviolet (EUV) projection lithography based on a ring field imaging system and a laser produced plasma source. The system uses three spherical mirrors and is capable of illuminating the extent of the mask plane by scanning either the primary mirror or the laser plasma source. The angles of radiation incident upon each mirror of the critical illumination condenser vary by less than eight (8) degrees. For example, the imaging system in which the critical illumination condenser is utilized has a 200 .mu.m source and requires a magnification of 26.times.. The three spherical mirror system constitutes a two mirror inverse Cassegrain, or Schwarzschild configuration, with a 25% area obstruction (50% linear obstruction). The third mirror provides the final pupil and image relay. The mirrors include a multilayer reflective coating which is reflective over a narrow bandwidth.

  1. Experimental Criticality Benchmarks for SNAP 10A/2 Reactor Cores

    SciTech Connect (OSTI)

    Krass, A.W.

    2005-12-19

    This report describes computational benchmark models for nuclear criticality derived from descriptions of the Systems for Nuclear Auxiliary Power (SNAP) Critical Assembly (SCA)-4B experimental criticality program conducted by Atomics International during the early 1960's. The selected experimental configurations consist of fueled SNAP 10A/2-type reactor cores subject to varied conditions of water immersion and reflection under experimental control to measure neutron multiplication. SNAP 10A/2-type reactor cores are compact volumes fueled and moderated with the hydride of highly enriched uranium-zirconium alloy. Specifications for the materials and geometry needed to describe a given experimental configuration for a model using MCNP5 are provided. The material and geometry specifications are adequate to permit user development of input for alternative nuclear safety codes, such as KENO. A total of 73 distinct experimental configurations are described.

  2. Regression coefficient maps showing that Nadir CD4+ count is correlated with regional white matter volumes (FDR q=0.05, critical P=0.03)

    E-Print Network [OSTI]

    Thompson, Paul

    Results Regression coefficient maps showing that Nadir CD4+ count is correlated with regional white matter volumes (FDR q=0.05, critical P=0.03) Regression coefficient maps showing that NAA levels of neurodegeneration. At each voxel in the brain, multiple regression was used to assess associations between regional

  3. On the critical temperatures of superconductors: a quantum gravity approach

    E-Print Network [OSTI]

    Andrea Gregori

    2010-07-06

    We consider superconductivity in the light of the quantum gravity theoretical framework introduced in [1]. In this framework, the degree of quantum delocalization depends on the geometry of the energy distribution along space. This results in a dependence of the critical temperature characterizing the transition to the superconducting phase on the complexity of the structure of a superconductor. We consider concrete examples, ranging from low to high temperature superconductors, and discuss how the critical temperature can be predicted once the quantum gravity effects are taken into account.

  4. SPHERICALLY SYMMETRIC RANDOM WALKS II. DIMENSIONALLY DEPENDENT CRITICAL BEHAVIOR

    E-Print Network [OSTI]

    Carl M. Bender; Peter N. Meisinger; Stefan Boettcher

    1995-06-06

    A recently developed model of random walks on a $D$-dimensional hyperspherical lattice, where $D$ is {\\sl not} restricted to integer values, is extended to include the possibility of creating and annihilating random walkers. Steady-state distributions of random walkers are obtained for all dimensions $D>0$ by solving a discrete eigenvalue problem. These distributions exhibit dimensionally dependent critical behavior as a function of the birth rate. This remarkably simple model exhibits a second-order phase transition with a nontrivial critical exponent for all dimensions $D>0$.

  5. The external field dependence of the BCS critical temperature

    E-Print Network [OSTI]

    Rupert L. Frank; Christian Hainzl; Robert Seiringer; Jan Philip Solovej

    2014-10-09

    We consider the Bardeen-Cooper-Schrieffer free energy functional for particles interacting via a two-body potential on a microscopic scale and in the presence of weak external fields varying on a macroscopic scale. We study the influence of the external fields on the critical temperature. We show that in the limit where the ratio between the microscopic and macroscopic scale tends to zero, the next to leading order of the critical temperature is determined by the lowest eigenvalue of the linearization of the Ginzburg-Landau equation.

  6. Renyi entropy of the critical O(N) model

    E-Print Network [OSTI]

    Anirbit Mukherjee

    2015-12-03

    In this article we explore a certain definition of "alternate quantization" for the critical O(N) model. We elaborate on a prescription to evaluate the Renyi entropy of alternately quantized critical O(N) model. We show that there exists new saddles of the q-Renyi free energy functional corresponding to putting certain combinations of the Kaluza-Klein modes into alternate quantization. This leads us to an analysis of trying to determine the true state of the theory by trying to ascertain the global minima among these saddle points.

  7. Criticality of environmental information obtainable by dynamically controlled quantum probes

    E-Print Network [OSTI]

    Analia Zwick; Gonzalo A. Alvarez; Gershon Kurizki

    2015-09-22

    A universal approach to decoherence control combined with quantum estimation theory reveals a critical behavior, akin to a phase transition, of the information obtainable by a qubit probe concerning the memory time of environmental fluctuations. This criticality emerges only when the probe is subject to dynamical control. It gives rise to a sharp transition between two dynamical phases characterized by either a short or long memory time compared to the probing time. This phase-transition of the environmental information is a fundamental feature that facilitates the attainment of the highest estimation precision of the environment memory-time and the characterization of probe dynamics.

  8. Resonances in two-electron atoms below the critical charge

    E-Print Network [OSTI]

    Karr, Jean-Philippe

    2015-01-01

    The critical nuclear charge Zc required for a heliumlike atom to have at least one bound state was recently determined with high accuracy from variational calculations. Analysis of the wave functions further suggested that the bound state changes smoothly into a shape resonance as Z crosses the critical value. Using variational calculations combined with the complex coordinate rotation method, we study the energy and width of the resonance for Z \\textless{} Zc, thus providing direct evidence of the validity of this hypothesis. The variation of the resonance width with Z is found to be in good agreement with a model derived from analysis of the 1/Z perturbation series.

  9. Variability-aware system-level design and analysis

    E-Print Network [OSTI]

    Chandra, Saumya

    2009-01-01

    on the critical path . . . . . . . . . . . . . .119 5.4of variations on critical path . . . . . Overall performanceAs the number of critical paths on a die increases (e.g. ,

  10. Estimated critical conditions for UF{sub 4}-oil systems in fully oil-reflected spherical geometry

    SciTech Connect (OSTI)

    Plaster, M.J.

    1997-05-01

    Paraffinic oil has been exposed to UF{sub 6} gas in seal exhaust pumps and cascade equipment at the Portsmouth Gaseous Diffusion Plant. The resulting mixture is more nuclearly reactive than mixtures of UO{sub 2}F{sub 2} and H{sub 2}O and is not bounded by the subcritical mass limits presented in several nuclear criticality safety guides. The purpose of this analysis is to determine several critical parameters; specifically, (1) k{sub {infinity}} and the critical mass for several enrichments and moderation levels and (2) the mass limits for these mixtures. The estimated critical masses for the UF{sub 4}-oil systems are smaller than for the UO{sub 2}F{sub 2}-H{sub 2}O systems. The suggested mass limits for the UF{sub 4}-oil systems are 0.240, 0.280, 0.350, 0.430, and 0.670, and 1.170 kg {sup 235}U for enrichments of 100, 50, 20, 10, 5, and 3 wt.% {sup 235}U respectively.

  11. Effect of Sea Level Rise

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum Based|DepartmentStatementofApril 25,EVthe next generationEffect of Sea Level

  12. Geometry-dependent critical currents in superconducting nanocircuits

    SciTech Connect (OSTI)

    Clem, John R.; Berggren, Karl K.

    2011-11-18

    In this paper, we calculate the critical currents in thin superconducting strips with sharp right-angle turns, 180{sup o} turnarounds, and more complicated geometries, where all the line widths are much smaller than the Pearl length {Lambda} = 2{lambda}{sup 2}/d. We define the critical current as the current that reduces the Gibbs-free-energy barrier to zero. We show that current crowding, which occurs whenever the current rounds a sharp turn, tends to reduce the critical current, but we also show that when the radius of curvature is less than the coherence length, this effect is partially compensated by a radius-of-curvature effect. We propose several patterns with rounded corners to avoid critical-current reduction due to current crowding. These results are relevant to superconducting nanowire single-photon detectors, where they suggest a means of improving the bias conditions and reducing dark counts. These results also have relevance to normal-metal nanocircuits, as these patterns can reduce the electrical resistance, electromigration, and hot spots caused by nonuniform heating.

  13. Critical Communications During and After a Solar Superstorm

    E-Print Network [OSTI]

    Schrijver, Karel

    Critical Communications During and After a Solar Superstorm 3 March 2011 #12;2 Overview ·FEMA's Mission ·Problem Statement ·Extreme Solar Weather Has Happened Before ·Assessing the Risk ·The Scenario citizens and first responders to ensure that as a nation we work together to build, sustain, and improve

  14. harmonic generation at a critical power in inhomogeneous doubly

    E-Print Network [OSTI]

    Soljaèiæ, Marin

    (2) and (3) harmonic generation at a critical power in inhomogeneous doubly resonant cavities- and third-harmonic generation via (2) and (3) nonlinearities. We find that conversion efficiency. Drummond, K. J. McNeil, and D. F. Walls, "Non-equilibrium transitions in sub/second harmonic generation I

  15. Identifying Vulnerabilities and Critical Requirements Using Criminal Court Proceeding

    E-Print Network [OSTI]

    Breaux, Travis D.

    , as applied to criminal court records to identify mitigating requirements that improve privacy protectionsIdentifying Vulnerabilities and Critical Requirements Using Criminal Court Proceeding Travis D,jdlewis,pnotto,anton}@ncsu.edu ABSTRACT Information systems governed by laws and regulations are subject to civil and criminal violations

  16. Identifying Vulnerabilities and Critical Requirements Using Criminal Court Proceedings

    E-Print Network [OSTI]

    Young, R. Michael

    and goal models, as applied to criminal court records to identify mitigating requirements. In a sustainableIdentifying Vulnerabilities and Critical Requirements Using Criminal Court Proceedings Travis D,jdlewis,pnotto,anton}@ncsu.edu Abstract Information systems governed by laws and regulations are subject to both civil and criminal

  17. A controlling norm for energy-critical Schrödinger maps

    E-Print Network [OSTI]

    Benjamin Dodson; Paul Smith

    2013-02-15

    We consider energy-critical Schroedinger maps with target either the sphere S^2 or hyperbolic plane H^2 and establish that a unique solution may be continued so long as a certain space-time L^4 norm remains bounded. This reduces the large data global wellposedness problem to that of controlling this norm.

  18. Critical behavior and universality in Levy spin glasses 

    E-Print Network [OSTI]

    Andresen, Juan Carlos; Janzen, Katharina; Katzgraber, Helmut G.

    2011-01-01

    or bimodal-distributed interactions. Corrections to scaling are large for Levy spin glasses. To overcome these and show that the critical exponents agree with the bimodal and Gaussian case, we perform an extended scaling of the two-point finite...

  19. Dynamical synapses causing self-organized criticality in neural networks

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS Dynamical synapses causing self-organized criticality in neural networks A. LEVINA1,2,3 , J more realistic) dynamical synapses14 in a spiking neural network, the neuronal avalanches turn from dynamics is robust to parameter changes. Consider a network of N integrate-and-fire neurons. Each neuron

  20. Quantum Criticality and Novel Phases: Summary and Outlook

    E-Print Network [OSTI]

    A. J. Schofield

    2010-01-24

    This conference summary and outlook provides a personal overview of the topics and themes of the August 2009 Dresden meeting on quantum criticality and novel phases. The dichotomy between the local moment and the itinerant views of magnetism is revisited and refreshed in new materials, new probes and new theoretical ideas. New universality and apparent zero temperature phases of matter move us beyond the old ideas of quantum criticality. This is accompanied by alternative pairing interactions and as yet unidentified phases developing in the vicinity of quantum critical points. In discussing novel order, the magnetic analogues of superconductivity are considered as candidate states for the hidden order that sometimes develops in the vicinity of quantum critical points in metallic systems. These analogues can be thought of as "pairing" in the particle-hole channel and are tabulated. This analogy is used to outline a framework to study the relation between ferromagnetic fluctuations and the propensity of a metal to nematic type phases which at weak coupling correspond to Pomeranchuk instabilities. This question can be related to the fundamental relations of Fermi liquid theory.

  1. I. INTRODUCTION Civil and critical infrastructure systems such as

    E-Print Network [OSTI]

    Oren, Shmuel S.

    of scientific principles to the design, maintenance and improvement of the critical infrastructures in our of any one element (e.g. generator, transmission line, transformer etc.). The last two decades brought System Engineering Research Center (PSERC) and by the Center for Electric Reliability Technology

  2. Multipath channels Path timing critical (versus amplitude information)

    E-Print Network [OSTI]

    Southern California, University of

    1 · Multipath channels · Path timing critical (versus amplitude information) ­ Certain modulations: PPM ­ Location/Ranging · Model ­ Delay spread ­ L paths (M choose L possible profiles) ­ Independent path amplitudes ­ Block constant channel ­ AW GN 0 100 200 300 400 500 600 -0.02 0 0.02 The Channel

  3. Art History (Critical Analysis Track) Bachelor of Arts

    E-Print Network [OSTI]

    Elzanowski, Marek

    Art History (Critical Analysis Track) Bachelor of Arts 201516 Degree Map First Year Fall 208 for ONE of these courses if focusing on Asian art. Milestone: Complete ARH 206 (by end Course Credit Course Credit Course Credit 1 Recommended for students interested in Art

  4. Art History (Critical Analysis Track) Bachelor of Science

    E-Print Network [OSTI]

    Elzanowski, Marek

    Art History (Critical Analysis Track) Bachelor of Science 201516 Degree Map First Year Fall 208 for ONE of these courses if focusing on Asian art. Milestone: Complete ARH 206 (by end ARH 2061 4 Math/Statistics Elective 4 ART Elective 4 General Elective 4 Total Credits 13

  5. 3 LANSCE: Mission-Critical for National Security

    E-Print Network [OSTI]

    Li, Hui

    3 LANSCE: Mission-Critical for National Security 7 Nuclear Energy for Our Challenging Future 12) and the Department of Energy (DOE). In 2011, the NNSA renewed the memorandum of understanding that affirms, and the Isotope Production Facility. A sixth facility, the Materials Test Station, is being developed. The linac

  6. Cost increases at fusion project going critical David Kramer

    E-Print Network [OSTI]

    be used to upgrade biofuels to higher energy content or to reduce CO2 Cost increases at fusion project going critical David Kramer Citation: Phys. Today 66(7), 24 (2013 Physics Today www.physicstoday.org issues and events H ow much will it cost to build what could well

  7. U.S. Department of Energy - Critical Materials Strategy

    SciTech Connect (OSTI)

    2010-12-01

    The Critical Materials Strategy builds on the Department’s previous work in this area and provides a foundation for future action. This Strategy is a first step toward a comprehensive response to the challenges before us. We hope it will also encourage others to engage in a dialogue about these issues and work together to achieve our Nation’s clean energy goals.

  8. Risk communication for critical civil infrastructure systems Jack Baker1

    E-Print Network [OSTI]

    Baker, Jack W.

    1 Risk communication for critical civil infrastructure systems Jack Baker1 , Jason Coray2 , Paul De for communicating risk within the context of infrastructure management decision support systems. A generic model-based management systems discussed in the paper includes the communication of risk to system users. The paper

  9. Critically Exploring the Virtual Possession Design Space Through Fieldwork and

    E-Print Network [OSTI]

    Critically Exploring the Virtual Possession Design Space Through Fieldwork and Constructive Design, photos, tickets); things that never had a lasting material form (e.g., electronic message archives devices and services (e.g., photo location information, music play histories, automatic and manual photo

  10. Critical Zones in Desert Fog: Aids to Multiscale Navigation

    E-Print Network [OSTI]

    Furnas, George W.

    Critical Zones in Desert Fog: Aids to Multiscale Navigation Susanne Jul Computer Science +1 734-763-0076 furnas@umich.edu ABSTRACT In this paper, we introduce the problem of "desert fog desert fog in multiscale electronic worlds. Prototypes of these aids have been implemented

  11. Criticality calculations with MCNP{sup TM}: A primer

    SciTech Connect (OSTI)

    Mendius, P.W. [ed.; Harmon, C.D. II; Busch, R.D.; Briesmeister, J.F.; Forster, R.A.

    1994-08-01

    The purpose of this Primer is to assist the nuclear criticality safety analyst to perform computer calculations using the Monte Carlo code MCNP. Because of the closure of many experimental facilities, reliance on computer simulation is increasing. Often the analyst has little experience with specific codes available at his/her facility. This Primer helps the analyst understand and use the MCNP Monte Carlo code for nuclear criticality analyses. It assumes no knowledge of or particular experience with Monte Carlo codes in general or with MCNP in particular. The document begins with a Quickstart chapter that introduces the basic concepts of using MCNP. The following chapters expand on those ideas, presenting a range of problems from simple cylinders to 3-dimensional lattices for calculating keff confidence intervals. Input files and results for all problems are included. The Primer can be used alone, but its best use is in conjunction with the MCNP4A manual. After completing the Primer, a criticality analyst should be capable of performing and understanding a majority of the calculations that will arise in the field of nuclear criticality safety.

  12. Critical Review Microbial Electrolysis Cells for High Yield Hydrogen Gas

    E-Print Network [OSTI]

    Critical Review Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic A S S E , , § A N D R E N ´E A . R O Z E N D A L | Hydrogen Energy Center, and Department of Civil.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield

  13. INTERNAL SOLITARY WAVES WITH A WEAKLY STRATIFIED CRITICAL LAYER

    E-Print Network [OSTI]

    horizontal shear flow and density stratification. On a long time scale, the waves evolve and reach a quasi, we invoke nonlinear effects to re- solve this singularity. Although viscosity and thermal-fluid limit is eventually taken. Crucially, the density stratification is assumed to be small at the critical

  14. Freedom in Kant's Critical Philosophy: The Keystone of Pure Reason 

    E-Print Network [OSTI]

    Aylsworth, Timothy J.

    2010-07-14

    The objective of my thesis was to examine Kant's concept of freedom and the role that it plays in his Critical philosophy. Each section deals with an interpretive or theoretical problem concerning freedom in the context of one of Kant's Critiques...

  15. Assessment of Critical Barriers and Opportunities to Accelerate Biofuels

    E-Print Network [OSTI]

    California at Davis, University of

    Assessment of Critical Barriers and Opportunities to Accelerate Biofuels and Biomethane 93 (735 Mgge) Feedstock Amount Technically Available Biomethane Potential (billion cubic feet) CNG (gge) Williams et al., CBC, 2015.; (7.74 GGE/MMBTU) Fraction in use Table ES.2. Biogas Technical

  16. Folk Psychology and Folk Morality: Response to Critics1

    E-Print Network [OSTI]

    Knobe, Joshua

    Folk Psychology and Folk Morality: Response to Critics1 Joshua Knobe Princeton University It is often implied, and sometimes explicitly asserted, that folk psychology is best understood as a kind of predictive device. The key contention of this widely held view is that people apply folk-psychological

  17. Earthquake research for the safer siting of critical facilities

    SciTech Connect (OSTI)

    Cluff, J.L. (ed.)

    1980-01-01

    The task of providing the necessities for living, such as adequate electrical power, water, and fuel, is becoming more complicated with time. Some of the facilities that provide these necessities would present potential hazards to the population if serious damage were to occur to them during earthquakes. Other facilities must remain operable immediately after an earthquake to provide life-support services to people who have been affected. The purpose of this report is to recommend research that will improve the information available to those who must decide where to site these critical facilities, and thereby mitigate the effects of the earthquake hazard. The term critical facility is used in this report to describe facilities that could seriously affect the public well-being through loss of life, large financial loss, or degradation of the environment if they were to fail. The term critical facility also is used to refer to facilities that, although they pose a limited hazard to the public, are considered critical because they must continue to function in the event of a disaster so that they can provide vital services.

  18. Structure and aggregation of colloids immersed in critical solvents

    E-Print Network [OSTI]

    T. F. Mohry; A. Macio?ek; S. Dietrich

    2012-01-27

    We consider an ensemble of spherical colloidal particles immersed in a near-critical solvent such as a binary liquid mixture close to its critical demixing point. The emerging long-ranged fluctuations of the corresponding order parameter of the solvent drive the divergence of the correlation length. Spatial confinements of these critical fluctuations by colloidal solute particles, acting as cavities in the fluctuating medium, restrict and modify the fluctuation spectrum in a way which depends on their relative configuration. This results in effective, so-called critical Casimir forces (CCFs) acting on the confining surfaces. Using the available knowledge about CCFs we study the structure and stability of such colloidal suspensions by employing an approach in terms of effective, one-component colloidal systems. Applying the approximation of pairwise additive CCFs we calculate the radial distribution function of the colloids, which is experimentally accessible. We analyze colloidal aggregation due to CCFs and thus allude to previous experimental studies which are still under debate

  19. WIPP-016, Rev. 0 Nuclear Criticality Safety Evaluation for

    E-Print Network [OSTI]

    WIPP-016, Rev. 0 Nuclear Criticality Safety Evaluation for Contact-Handled Transuranic Waste Department of Energy review required before public release Name/Org: __________/WIPP Project Date 05-HANDLED TRANSURANIC WASTE AT THE WASTE ISOLATION PILOT PLANT WIPP-016, REV. 0 MAY 2008 OFFICIAL USE ONLY Washington

  20. Call for Papers Conference on Critical Refugee Studies

    E-Print Network [OSTI]

    Saldin, Dilano

    Call for Papers Conference on Critical Refugee Studies University of Wisconsin-Milwaukee November 3. Recognized by international proxy after World War II, the identity category of refugee has a history as long invention of the category of refugee as a means to compare the experiences of displaced persons across time

  1. CRAD, Criticality Safety- Idaho Accelerated Retrieval Project Phase II

    Broader source: Energy.gov [DOE]

    A section of Appendix C to DOE G 226.1-2 "Federal Line Management Oversight of Department of Energy Nuclear Facilities." Consists of Criteria Review and Approach Documents (CRADs) used for a February 2006 Commencement of Operations assessment of the Criticality Safety program at the Idaho Accelerated Retrieval Project Phase II.

  2. Additional critical experiments for computer code validation base

    SciTech Connect (OSTI)

    Elliott, E.P.; Tollefson, D.A.; Vornehm, R.G.

    1994-04-25

    This paper describes the validation, in accordance with ANSI/ANS-8.1-1983(R1988), of KENO V.a using the 27-group ENDF/B-IV cross section library for some neutronic systems containing highly-enriched uranium, carbon, and hydrogen. This constituent combination is present in many packaging applications for the safe transportation of fissile and fissionable materials. The validation has been performed for two separate computational platforms: an IBM 3090 mainframe and an HP 9000 Series 700 workstation, both using the Oak Ridge Y-12 Plant Nuclear Criticality Safety Software (NCSS) code package. Critical experiments performed at the Oak Ridge Critical Experiments Facility in support of the Rover reactor program were identified as having the constitutents desired for this validation as well as sufficient experimental detail to allow accurate construction of KENO V.a calculational models. Calculated values of k{sub eff} for the Rover experiments, which contain uranium, carbon, and hydrogen, are between 1.0012 {+-} 0.0026 and 1.0245 {+-} 0.0023. These experiments can now be added to KENO V.a and other computer code critical experiment data bases which are used for validation and to establish upper limits on calculated values of k{sub eff} for specific applications.

  3. The World and the Machine" A Critical Perspective on

    E-Print Network [OSTI]

    Finkelstein, Anthony

    the machine". We identify items in the world" to be put on a research agenda in order to restore the balanceThe World and the Machine" A Critical Perspective on Process Technology Wolfgang Emmerich, Anthony open and discursive. 1 Introduction In the quest for a new research agenda for process technology, we

  4. Mixed-Criticality on Multicore (MC2 ): A Status

    E-Print Network [OSTI]

    Anderson, James

    . Anderson Department of Computer Science, The University of North Carolina at Chapel Hill {namhoonk Chapel Hill and Northrop Grumman Corp. proposed a mixed-criticality scheduling framework for multicore proposed by Ward et al. [7]. Specifically, they proposed two cache-management techniques, called cache

  5. Electrorecycling of Critical and Value Metals from Mobile Electronics

    SciTech Connect (OSTI)

    Tedd E. Lister; Peming Wang; Andre Anderko

    2014-09-01

    Mobile electronic devices such as smart phones and tablets are a significant source of valuable metals that should be recycled. Each year over a billion devices are sold world-wide and the average life is only a couple years. Value metals in phones are gold, palladium, silver, copper, cobalt and nickel. Devices now contain increasing amounts of rare earth elements (REE). In recent years the supply chain for REE has moved almost exclusively to China. They are contained in displays, speakers and vibrators within the devices. By US Department of Energy (DOE) classification, specific REEs (Nd, Dy, Eu, Tb and Y) are considered critical while others (Ce, La and Pr) are deemed near critical. Effective recycling schemes should include the recovery of these critical materials. By including more value materials in a recovery scheme, more value can be obtained by product diversification and less waste metals remains to be disposed of. REEs are mined as a group such that when specific elements become critical significantly more ore must be processed to capture the dilute but valuable critical elements. Targeted recycling of items containing the more of the less available critical materials could address their future criticality. This presentation will describe work in developing aqueous electrochemistry-based schemes for recycling metals from scrap mobile electronics. The electrorecycling process generates oxidizing agents at an anode while reducing dissolved metals at the cathode. E vs pH diagrams and metals dissolution experiments are used to assess effectiveness of various solution chemistries. Although several schemes were envisioned, a two stages process has been the focus of work: 1) initial dissolution of Cu, Sn, Ag and magnet materials using Fe+3 generated in acidic sulfate and 2) final dissolution of Pd and Au using Cl2 generated in an HCl solution. Experiments were performed using simulated metal mixtures. Both Cu and Ag were recovered at ~ 97% using Fe+3 while leaving Au and Ag intact. REE were extracted from the dissolved mixture using conventional methods. A discussion of future research directions will be discussed.

  6. Criticality calculations with MCNP{trademark}: A primer

    SciTech Connect (OSTI)

    Harmon, C.D. II; Busch, R.D.; Briesmeister, J.F.; Forster, R.A. [New Mexico Univ., Albuquerque, NM (United States)

    1994-06-06

    With the closure of many experimental facilities, the nuclear criticality safety analyst increasingly is required to rely on computer calculations to identify safe limits for the handling and storage of fissile materials. However, in many cases, the analyst has little experience with the specific codes available at his/her facility. This primer will help you, the analyst, understand and use the MCNP Monte Carlo code for nuclear criticality safety analyses. It assumes that you have a college education in a technical field. There is no assumption of familiarity with Monte Carlo codes in general or with MCNP in particular. Appendix A gives an introduction to Monte Carlo techniques. The primer is designed to teach by example, with each example illustrating two or three features of MCNP that are useful in criticality analyses. Beginning with a Quickstart chapter, the primer gives an overview of the basic requirements for MCNP input and allows you to run a simple criticality problem with MCNP. This chapter is not designed to explain either the input or the MCNP options in detail; but rather it introduces basic concepts that are further explained in following chapters. Each chapter begins with a list of basic objectives that identify the goal of the chapter, and a list of the individual MCNP features that are covered in detail in the unique chapter example problems. It is expected that on completion of the primer you will be comfortable using MCNP in criticality calculations and will be capable of handling 80 to 90 percent of the situations that normally arise in a facility. The primer provides a set of basic input files that you can selectively modify to fit the particular problem at hand.

  7. Validation of Criticality Safety Calculations with SCALE 6.2

    SciTech Connect (OSTI)

    Marshall, William BJ J [ORNL] [ORNL; Wiarda, Dorothea [ORNL] [ORNL; Celik, Cihangir [ORNL] [ORNL; Rearden, Bradley T [ORNL] [ORNL

    2013-01-01

    SCALE 6.2 provides numerous updates in nuclear data, nuclear data processing, and computational tools utilized in the criticality safety calculational sequences relative to SCALE 6.1. A new 252-group ENDF/B-VII.0 multigroup neutron library, improved ENDF/B-VII.0 continuous energy data, as well as the previously deployed 238-group ENDF/B-VII.0 neutron library are included in SCALE 6.2 for criticality safety analysis. The performance of all three libraries for keff calculations is examined with a broad sampling of critical experiment models covering a range of fuels and moderators. Critical experiments from the International Handbook of Evaluated Criticality Safety Benchmark Experiments (IHECSBE) that are available in the SCALE Verified, Archived Library of Inputs and Data (VALID) are used in this validation effort. Over 300 cases are used in the validation of KENO V.a, and a more limited set of approximately 50 configurations are used for KENO-VI validation. Additionally, some KENO V.a cases are converted to KENO-VI models so that an equivalent set of experiments can be used to validate both codes. For continuous-energy calculations, SCALE 6.2 provides improved performance relative to SCALE 6.1 in most areas with notable improvements in fuel pin lattice cases, particularly those with mixed oxide fuel. Multigroup calculations with the 252-group library also demonstrate improved performance for fuel lattices, uranium (high and intermediate enrichment) and plutonium metal experiments, and plutonium solution systems. Overall, SCALE 6.2 provides equivalent or smaller biases than SCALE 6.1, and the two versions of KENO provide similar results on the same suite of problems.

  8. A method for finding the statically sensitized critical path in VLSI circuits 

    E-Print Network [OSTI]

    Sen, Anindita

    1995-01-01

    The longest sensitizable paths of a circuit are referred to as the critical paths of the circuit. Finding all the critical paths in a circuit is called the critical path problem. There are various methods at present to find the critical path of a...

  9. Critical Path Analysis of TCP Transactions Paul Barford and Mark Crovella

    E-Print Network [OSTI]

    Banerjee, Suman

    Critical Path Analysis of TCP Transactions Paul Barford and Mark Crovella Abstract Improving critical path analysis. By constructing and pro#12;ling the critical path, it is possible to determine what implemented our technique in a tool called tcpeval that automates critical path analysis for Web transactions

  10. A Cost-Effective Critical Path Approach for Service Priority Optimization in the Grid Computing Economy

    E-Print Network [OSTI]

    Lin, Zhangxi

    1 A Cost-Effective Critical Path Approach for Service Priority Optimization in the Grid Computing as a prioritized PERT graph and prove that the localized conditional critical path, which is based on the cost on the non- critical paths with respect to a given critical path. Keywords: Grid computing, computing power

  11. A Dynamic Critical Path Algorithm for Scheduling Scientific Workflow Applications on Global Grids

    E-Print Network [OSTI]

    Melbourne, University of

    A Dynamic Critical Path Algorithm for Scheduling Scientific Workflow Applications on Global Grids for the execution of performance driven Grid applications. In this paper, we propose a Dynamic Critical Path (DCP the critical path in the workflow task graph at every step. It assigns priority to a task in the critical path

  12. A Taxonomy of Computer-supported Critics Norhayati Mohd Ali, John Hosking

    E-Print Network [OSTI]

    Grundy, John

    A Taxonomy of Computer-supported Critics Norhayati Mohd Ali, John Hosking Department of Computer in providing feedback to users. In this paper we propose an initial critic taxonomy based on our review of the critic literature. We present the groups and elements of the critic taxonomy and explain the groups

  13. The neutron response of a $^{7}LIF$ thermoluminescent dosimeter incorporated in the UKAEA criticality dosimeter

    E-Print Network [OSTI]

    Eid, A M

    1976-01-01

    The neutron response of a $^{7}LIF$ thermoluminescent dosimeter incorporated in the UKAEA criticality dosimeter

  14. Silver (Ag) Transport Mechanisms in TRISO Coated Particles: A Critical Review

    SciTech Connect (OSTI)

    IJ van Rooyen; ML Dunzik-Gougar; PM van Rooyen

    2014-05-01

    Transport of 110mAg in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coated particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE’s fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.

  15. Silver (Ag) Transport Mechanisms in TRISO coated particles: A Critical Review

    SciTech Connect (OSTI)

    I J van Rooyen; J H Neethling; J A A Engelbrecht; P M van Rooyen; G Strydom

    2012-10-01

    Transport of 110mAg in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coated particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE’s fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.

  16. x Integration Level x CAN Controller Architecture

    E-Print Network [OSTI]

    Kozak, Victor R.

    ¥ Application ¥ Signaling ¥ Bus Failure Management ¥ Signaling ¥ Bus Failure Management Microcontroller Controller ¥ Signaling ¥ Bus Failure Management ¥ Signaling ¥ Bus Failure Management Microcontroller peripherals cause a lower CPU load than do stand-alone controllers. The most critical factor is the amount

  17. Impact of Anglo-American new criticism on modern Arabic discourse : the case of Shi 'r (Poetry Magazine) 

    E-Print Network [OSTI]

    Hamdan, Yousef Hussein Mahmoud

    2013-11-26

    New Criticism has had a profound impact on Arabic critical thought since the early 1950s. The reasons behind this vary from one critic to another. Some have employed New Criticism to analyse the poetic movement of Shi r ...

  18. Company Level Imports Explanatory Notes

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry NaturalPrices1 Table 1.101Company Level Imports Explanatory Notes

  19. Noise and microresonance of critical current in Josephson junction induced by Kondo trap states

    E-Print Network [OSTI]

    Ansari, Mohammad H

    2011-01-01

    We analyze the impact of trap states in the oxide layer of a superconducting tunnel junctions, on the fluctuation of the Josephson critical current, thus on coherence in superconducting qubits. Two mechanisms are usually considered: the current blockage due to repulsion at the occupied trap states, and the noise from electrons hopping across a trap. We extend previous studies of noninteracting traps to the case where the traps have on-site electron repulsion inside one ballistic channel. The repulsion not only allows the appropriate temperature dependence of 1/f noise, but also is a control to the coupling between the computational qubit and the spurious two-level systems inside the oxide dielectric. We use second order perturbation theory which allows to obtain analytical formulae for the interacting bound states and spectral weights, limited to small and intermediate repulsions. Remarkably, it still reproduces the main features of the model as identified from the Numerical Renormalization Group. We present ...

  20. Unconventional minimal subtraction and Bogoliubov-Parasyuk-Hepp-Zimmermann method: Massive scalar theory and critical exponents

    SciTech Connect (OSTI)

    Carvalho, Paulo R. S.; Leite, Marcelo M.

    2013-09-15

    We introduce a simpler although unconventional minimal subtraction renormalization procedure in the case of a massive scalar ??{sup 4} theory in Euclidean space using dimensional regularization. We show that this method is very similar to its counterpart in massless field theory. In particular, the choice of using the bare mass at higher perturbative order instead of employing its tree-level counterpart eliminates all tadpole insertions at that order. As an application, we compute diagrammatically the critical exponents ? and ? at least up to two loops. We perform an explicit comparison with the Bogoliubov-Parasyuk-Hepp-Zimmermann (BPHZ) method at the same loop order, show that the proposed method requires fewer diagrams and establish a connection between the two approaches.

  1. Runtime deadlock analysis for system level design

    E-Print Network [OSTI]

    Cheung, Eric; Chen, Xi; Hsieh, Harry; Davare, Abhijit; Sangiovanni-Vincentelli, Alberto; Watanabe, Yosinori

    2009-01-01

    workshop on high level design validation and test, Nov. 2001Metropolis, and two real world design examples, which aredetection · System-level design · SystemC · Metropolis E.

  2. Critical magnetic field of surface superconductivity in lead

    SciTech Connect (OSTI)

    Khlyustikov, I. N., E-mail: khly@kapitza.ras.ru [Russian Academy of Sciences, Kapitza Institute of Physical Problems (Russian Federation)

    2011-12-15

    The critical superconductivity field H{sub c3} is measured on lead single crystals. It is shown that the temperature dependence of H{sub c3}/H{sub c} in the vicinity of superconducting transition temperature T{sub c} is essentially nonlinear. Relative changes in the value of H{sub c3}/H{sub c} reach approximately 30%, which cannot be described by the Ginzburg-Landau theory. The experimental temperature dependences lead to the conclusion that the surface superconducting transition temperature noticeably exceeds the superconducting transition temperature in the bulk of the semiconductor. The differences in the critical temperatures and in the Ginzburg-Landau parameters for lead are estimated.

  3. Discussion of measurements of supersaturation and critical gas saturation

    SciTech Connect (OSTI)

    Saidi, A.M.

    1994-06-01

    In Measurements of Supersaturation and Critical Gas Saturation'' (SPE Formation Evaluation, Dec. 1992, Page 337) Firoozabadi et al. reported that several expansion solution-gas-drive experiments at pressure-decline rates much higher than usually occur in actual reservoirs terminated at the onset of gas production.'' For this reason, they neither envisaged a gas/oil separator for measuring the GOR evolution, which is an important parameter for establishing critical gas saturation, S[sub gc], nor allowed sufficient pressure decline to measure the evolution of upward gas migration to confirm their low measured S[sub gc]. This confirmation was needed because their results contradict those of Dumore, Madaoui, and Moulu and Longeron.

  4. U.S. Department of Energy Critical Materials Strategy

    SciTech Connect (OSTI)

    Bauer, D.; Diamond, D.; Li, J.; Sandalow, D.; Telleen, P.; Wanner, B.

    2010-12-01

    This report examines the role of rare earth metals and other materials in the clean energy economy. It was prepared by the U.S. Department of Energy (DOE) based on data collected and research performed during 2010. Its main conclusions include: (a) Several clean energy technologies -- including wind turbines, electric vehicles, photovoltaic cells and fluorescent lighting -- use materials at risk of supply disruptions in the short term. Those risks will generally decrease in the medium and long term. (b) Clean energy technologies currently constitute about 20 percent of global consumption of critical materials. As clean energy technologies are deployed more widely in the decades ahead, their share of global consumption of critical materials will likely grow. (c) Of the materials analyzed, five rare earth metals (dysprosium, neodymium, terbium, europium and yttrium), as well as indium, are assessed as most critical in the short term. For this purpose, 'criticality' is a measure that combines importance to the clean energy economy and risk of supply disruption. (d) Sound policies and strategic investments can reduce the risk of supply disruptions, especially in the medium and long term. (e) Data with respect to many of the issues considered in this report are sparse. In the report, DOE describes plans to (i) develop its first integrated research agenda addressing critical materials, building on three technical workshops convened by the Department during November and December 2010; (ii) strengthen its capacity for information-gathering on this topic; and (iii) work closely with international partners, including Japan and Europe, to reduce vulnerability to supply disruptions and address critical material needs. DOE will work with other stakeholders -- including interagency colleagues, Congress and the public -- to shape policy tools that strengthen the United States' strategic capabilities. DOE also announces its plan to develop an updated critical materials strategy, based upon additional events and information, by the end of 2011.DOE's strategy with respect to critical materials rests on three pillars. First, diversified global supply chains are essential. To manage supply risk, multiple sources of materials are required. This means taking steps to facilitate extraction, processing and manufacturing here in the United States, as well as encouraging other nations to expedite alternative supplies. In all cases, extraction and processing should be done in an environmentally sound manner. Second, substitutes must be developed. Research leading to material and technology substitutes will improve flexibility and help meet the material needs of the clean energy economy. Third, recycling, reuse and more efficient use could significantly lower world demand for newly extracted materials. Research into recycling processes coupled with well-designed policies will help make recycling economically viable over time.The scope of this report is limited. It does not address the material needs of the entire economy, the entire energy sector or even all clean energy technologies. Time and resource limitations precluded a comprehensive scope. Among the topics that merit additional research are the use of rare earth metals in catalytic converters and in petroleum refining. These topics are discussed briefly in Chapter 2.

  5. Thermal conductivity at a disordered quantum critical point

    E-Print Network [OSTI]

    Hartnoll, Sean A; Santos, Jorge E

    2015-01-01

    Strongly disordered and strongly interacting quantum critical points are difficult to access with conventional field theoretic methods. They are, however, both experimentally important and theoretically interesting. In particular, they are expected to realize universal incoherent transport. Such disordered quantum critical theories have recently been constructed holographically by deforming a CFT by marginally relevant disorder. In this paper we find additional disordered fixed points via relevant disordered deformations of a holographic CFT. Using recently developed methods in holographic transport, we characterize the thermal conductivity in both sets of theories in 1+1 dimensions. The thermal conductivity is found to tend to a constant at low temperatures in one class of fixed points, and to scale as $T^{0.3}$ in the other. Furthermore, in all cases the thermal conductivity exhibits discrete scale invariance, with logarithmic in temperature oscillations superimposed on the low temperature scaling behavior....

  6. Lowering critical cooling rate for forming bulk metallic glass

    SciTech Connect (OSTI)

    Shen, T.D.; Schwarz, R.B. [MS G755, MST-8, Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2006-02-27

    Small volumes of Pd{sub 44}Ni{sub 10}Cu{sub 26}P{sub 20} and Pd{sub 43.2}Ni{sub 8.8}Cu{sub 28}P{sub 20} were encapsulated in B{sub 2}O{sub 3} and thermally cycled between T{sub g}-60 deg. C and T{sub l}+60 deg. C, where T{sub g} and T{sub l} denote the alloys' glass transition and liquidus temperatures. After this thermal treatment, the critical cooling rates (CCRs) for glass formation can be lowered by an order of magnitude, resulting in a critical cooling rate significantly lower than that reported for any other glass forming alloy melt. These experiments demonstrate that the CCR is not constant but strongly dependent on the degree of heterogeneous nucleation.

  7. Criticality safety aspects of K-25 Building uranium deposit removal

    SciTech Connect (OSTI)

    Haire, M.J.; Jordan, W.C. [Oak Ridge National Lab., TN (United States); Ingram, J.C. III; Stinnet, E.C. Jr. [Oak Ridge K-25 Site, TN (United States)

    1995-12-31

    The K-25 Building of the Oak Ridge Gaseous Diffusion Plant (now the K-25 Site) went into operation during World War II as the first large scale production plant to separate {sup 235}U from uranium by the gaseous diffusion process. It operated successfully until 1964, when it was placed in a stand-by mode. The Department of Energy has initiated a decontamination and decommissioning program. The primary objective of the Deposit Removal (DR) Project is to improve the nuclear criticality safety of the K-25 Building by removing enriched uranium deposits from unfavorable-geometry process equipment to below minimum critical mass. The method utilized to accomplish this are detailed in this report.

  8. Critical links and nonlocal rerouting in complex supply networks

    E-Print Network [OSTI]

    Witthaut, Dirk; Zhang, Xiaozhu; Hallerberg, Sarah; Timme, Marc

    2015-01-01

    Link failures repeatedly induce large-scale outages in power grids and other supply networks. Yet, it is still not well understood, which links are particularly prone to inducing such outages. Here we analyze how the nature and location of each link impact the network's capability to maintain stable supply. We propose two criteria to identify critical links on the basis of the topology and the load distribution of the network prior to link failure. They are determined via a link's redundant capacity and a renormalized linear response theory we derive. These criteria outperform critical link prediction based on local measures such as loads. The results not only further our understanding of the physics of supply networks in general. As both criteria are available before any outage from the state of normal operation, they may also help real-time monitoring of grid operation, employing counter-measures and support network planning and design.

  9. Global regularity of critical Schrödinger maps: subthreshold dispersed energy

    E-Print Network [OSTI]

    Paul Smith

    2012-12-19

    We consider the energy-critical Schroedinger map initial value problem with smooth initial data from R^2 into the sphere S^2. Given sufficiently energy-dispersed data with subthreshold energy, we prove that the system admits a unique global smooth solution. This improves earlier analogous conditional results. The key behind this improvement lies in exploiting estimates on the commutator of the Schroedinger map and harmonic map heat flows.

  10. Multibump solutions for quasilinear elliptic equations with critical growth

    SciTech Connect (OSTI)

    Liu, Jiaquan; Wang, Zhi-Qiang; Wu, Xian

    2013-12-15

    The current paper is concerned with constructing multibump solutions for a class of quasilinear Schrödinger equations with critical growth. This extends the classical results of Coti Zelati and Rabinowitz [Commun. Pure Appl. Math. 45, 1217–1269 (1992)] for semilinear equations as well as recent work of Liu, Wang, and Guo [J. Funct. Anal. 262, 4040–4102 (2012)] for quasilinear problems with subcritical growth. The periodicity of the potentials is used to glue ground state solutions to construct multibump bound state solutions.

  11. Critical surface for explosions of rotational core-collapse supernovae

    SciTech Connect (OSTI)

    Iwakami, Wakana; Nagakura, Hiroki [Yukawa Institute for Theoretical Physics, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto, 606-8502 (Japan); Yamada, Shoichi, E-mail: wakana@heap.phys.waseda.ac.jp [Advanced Research Institute for Science and Engineering, Waseda University, 3-4-1, Okubo, Shinjuku, Tokyo, 169-8555 (Japan)

    2014-09-20

    The effect of rotation on the explosion of core-collapse supernovae is investigated systematically in three-dimensional simulations. In order to obtain the critical conditions for explosion as a function of mass accretion rate, neutrino luminosity, and specific angular momentum, rigidly rotating matter was injected from the outer boundary with an angular momentum, which is increased every 500 ms. It is found that there is a critical value of the specific angular momentum, above which the standing shock wave revives, for a given combination of mass accretion rate and neutrino luminosity, i.e., an explosion can occur by rotation even if the neutrino luminosity is lower than the critical value for a given mass accretion rate in non-rotational models. The coupling of rotation and hydrodynamical instabilities plays an important role in characterizing the dynamics of shock revival for the range of specific angular momentum that are supposed to be realistic. Contrary to expectations from past studies, the most rapidly expanding direction of the shock wave is not aligned with the rotation axis. Being perpendicular to the rotation axis on average, it can be oriented in various directions. Its dispersion is small when the spiral mode of the standing accretion shock instability (SASI) governs the dynamics, while it is large when neutrino-driven convection is dominant. As a result of the comparison between two-dimensional and three-dimensional rotational models, it is found that m ? 0 modes of neutrino-driven convection or SASI are important for shock revival around the critical surface.

  12. Nuclear Criticality as a Contributor to Gamma Ray Burst Events

    E-Print Network [OSTI]

    Robert Bruce Hayes

    2013-01-15

    Most gamma ray bursts are able to be explained using supernovae related phenomenon. Some measured results still lack compelling explanations and a contributory cause from nuclear criticality is proposed. This is shown to have general properties consistent with various known gamma ray burst properties. The galactic origin of fast rise exponential decay gamma ray bursts is considered a strong candidate for these types of events.

  13. Critical issues in process control system security : DHS spares project.

    SciTech Connect (OSTI)

    Hernandez, Jacquelynne; McIntyre, Annie; Henrie, Morgan

    2010-10-01

    The goals of this event are: (1) Discuss the next-generation issues and emerging risks in cyber security for control systems; (2) Review and discuss common control system architectures; (3) Discuss the role of policy, standards, and supply chain issues; (4) Interact to determine the most pertinent risks and most critical areas of the architecture; and (5) Merge feedback from Control System Managers, Engineers, IT, and Auditors.

  14. Nuclear criticality safety engineer qualification program utilizing SAT

    SciTech Connect (OSTI)

    Baltimore, C.J.; Dean, J.C.; Henson, T.L. [Lockheed Martin Utility Services, Inc., Paducah, KY (United States)

    1996-12-31

    As part of the privatization process of the U.S. uranium enrichment plants, the Paducah Gaseous Diffusion Plant (PGDP) and the Portsmouth Gaseous Diffusion Plant (PORTS) have been in transition from U.S. Department of Energy (DOE) regulatory oversight to U.S. Nuclear Regulatory Commission (NRC) oversight since July 1993. One of the focus areas of this transition has been training and qualification of plant personnel who perform tasks important to nuclear safety, such as nuclear criticality safety (NCS) engineers.

  15. Recent Use of Covariance Data for Criticality Safety Assessment

    SciTech Connect (OSTI)

    Rearden, Bradley T [ORNL; Mueller, Don [ORNL

    2008-01-01

    The TSUNAMI codes of the Oak Ridge National Laboratory SCALE code system were applied to a burnup credit application to demonstrate the use of sensitivity and uncertainty analysis with recent cross section covariance data for criticality safety code and data validation. The use of sensitivity and uncertainty analysis provides for the assessment of a defensible computational bias, bias uncertainty, and gap analysis for a complex system that otherwise could be assessed only through the use of expert judgment and conservative assumptions.

  16. Nonclassicality and criticality in symmetry-protected magnetic phases

    E-Print Network [OSTI]

    Matthew J. M. Power; Steve Campbell; Maria Moreno-Cardoner; Gabriele De Chiara

    2015-06-08

    Quantum and global discord in a spin-1 Heisenberg chain subject to single-ion anisotropy (uniaxial field) are studied using exact diagonalisation and the density matrix renormalisation group (DMRG). We find that these measures of quantum nonclassicality are able to detect the quantum phase transitions confining the symmetry protected Haldane phase and show critical scaling with universal exponents. Moreover, in the case of thermal states, we find that quantum discord can increase with increasing temperature.

  17. An evaluation of the critical mechanical properties of filled elastomers 

    E-Print Network [OSTI]

    Gibson, Patrick Arthur

    1966-01-01

    by the combined forces of gravity, grain shrinkage, and thermal cycling. Therefore, if uniaxial teste are to be used, some correla- tion must be found to relate uniaxial data with those of biaxial and triaxial data. Because structural viscoelastics are a... possible. ABSTRACT An Evaluation of the Critical Mechanical Properties of Filled Elastomers Patrick A. Gibson, B. S. , Texas ASM University Directed by: Dr. William B. Ledbetter A test procedure is developed for the uniaxial tensile testing...

  18. The Baxter Q Operator of Critical Dense Polymers

    E-Print Network [OSTI]

    Alessandro Nigro

    2009-09-07

    We consider critical dense polymers ${\\cal L}_{1,2}$, corresponding to a logarithmic conformal field theory with central charge $c=-2$. An elegant decomposition of the Baxter $Q$ operator is obtained in terms of a finite number of lattice integrals of motion. All local, non local and dual non local involutive charges are introduced directly on the lattice and their continuum limit is found to agree with the expressions predicted by conformal field theory. A highly non trivial operator $\\Psi(\

  19. Critical Ising interfaces in multiply-connected domains

    E-Print Network [OSTI]

    Konstantin Izyurov

    2015-03-13

    We prove a general result on convergence of interfaces in the critical planar Ising model to conformally invariant curves absolutely continuous with respect to SLE(3). Our setup includes multiple interfaces on arbitrary finitely connected domains, and we also treat the radial SLE case. In the case of simply and doubly connected domains, the limiting processes are described explicitly in terms of rational and elliptic functions, respectively.

  20. Neural Network Based Intrusion Detection System for Critical Infrastructures

    SciTech Connect (OSTI)

    Todd Vollmer; Ondrej Linda; Milos Manic

    2009-07-01

    Resiliency and security in control systems such as SCADA and Nuclear plant’s in today’s world of hackers and malware are a relevant concern. Computer systems used within critical infrastructures to control physical functions are not immune to the threat of cyber attacks and may be potentially vulnerable. Tailoring an intrusion detection system to the specifics of critical infrastructures can significantly improve the security of such systems. The IDS-NNM – Intrusion Detection System using Neural Network based Modeling, is presented in this paper. The main contributions of this work are: 1) the use and analyses of real network data (data recorded from an existing critical infrastructure); 2) the development of a specific window based feature extraction technique; 3) the construction of training dataset using randomly generated intrusion vectors; 4) the use of a combination of two neural network learning algorithms – the Error-Back Propagation and Levenberg-Marquardt, for normal behavior modeling. The presented algorithm was evaluated on previously unseen network data. The IDS-NNM algorithm proved to be capable of capturing all intrusion attempts presented in the network communication while not generating any false alerts.

  1. CRITICAL ISSUES IN HIGH END COMPUTING - FINAL REPORT

    SciTech Connect (OSTI)

    Corones, James

    2013-09-23

    High-End computing (HEC) has been a driver for advances in science and engineering for the past four decades. Increasingly HEC has become a significant element in the national security, economic vitality, and competitiveness of the United States. Advances in HEC provide results that cut across traditional disciplinary and organizational boundaries. This program provides opportunities to share information about HEC systems and computational techniques across multiple disciplines and organizations through conferences and exhibitions of HEC advances held in Washington DC so that mission agency staff, scientists, and industry can come together with White House, Congressional and Legislative staff in an environment conducive to the sharing of technical information, accomplishments, goals, and plans. A common thread across this series of conferences is the understanding of computational science and applied mathematics techniques across a diverse set of application areas of interest to the Nation. The specific objectives of this program are: Program Objective 1. To provide opportunities to share information about advances in high-end computing systems and computational techniques between mission critical agencies, agency laboratories, academics, and industry. Program Objective 2. To gather pertinent data, address specific topics of wide interest to mission critical agencies. Program Objective 3. To promote a continuing discussion of critical issues in high-end computing. Program Objective 4.To provide a venue where a multidisciplinary scientific audience can discuss the difficulties applying computational science techniques to specific problems and can specify future research that, if successful, will eliminate these problems.

  2. Nambu-Goldstone Effective Theory of Information at Quantum Criticality

    E-Print Network [OSTI]

    Dvali, Gia; Gomez, Cesar; Wintergerst, Nico

    2015-01-01

    We establish a fundamental connection between quantum criticality of a many-body system, such as Bose-Einstein condensates, and its capacity of information-storage and processing. For deriving the effective theory of modes in the vicinity of the quantum critical point we develop a new method by mapping a Bose-Einstein condensate of $N$-particles onto a sigma model with a continuous global (pseudo)symmetry that mixes bosons of different momenta. The Bogolyubov modes of the condensate are mapped onto the Goldstone modes of the sigma model, which become gapless at the critical point. These gapless Goldstone modes are the quantum carriers of information and entropy. Analyzing their effective theory, we observe the information-processing properties strikingly similar to the ones predicted by the black hole portrait. The energy cost per qubit of information-storage vanishes in the large-$N$ limit and the total information-storage capacity increases with $N$ either exponentially or as a power law. The longevity of i...

  3. Toward Developing Genetic Algorithms to Aid in Critical Infrastructure Modeling

    SciTech Connect (OSTI)

    Not Available

    2007-05-01

    Today’s society relies upon an array of complex national and international infrastructure networks such as transportation, telecommunication, financial and energy. Understanding these interdependencies is necessary in order to protect our critical infrastructure. The Critical Infrastructure Modeling System, CIMS©, examines the interrelationships between infrastructure networks. CIMS© development is sponsored by the National Security Division at the Idaho National Laboratory (INL) in its ongoing mission for providing critical infrastructure protection and preparedness. A genetic algorithm (GA) is an optimization technique based on Darwin’s theory of evolution. A GA can be coupled with CIMS© to search for optimum ways to protect infrastructure assets. This includes identifying optimum assets to enforce or protect, testing the addition of or change to infrastructure before implementation, or finding the optimum response to an emergency for response planning. This paper describes the addition of a GA to infrastructure modeling for infrastructure planning. It first introduces the CIMS© infrastructure modeling software used as the modeling engine to support the GA. Next, the GA techniques and parameters are defined. Then a test scenario illustrates the integration with CIMS© and the preliminary results.

  4. Experimental critical parameters of plutonium metal cylinders flooded with water

    SciTech Connect (OSTI)

    NONE

    1996-07-01

    Forty-nine critical configurations are reported for experiments involving arrays of 3 kg plutonium metal cylinders moderated and reflected by water. Thirty-four of these describe systems assembled in the laboratory, while 15 others are derived critical parameters inferred from 46 subcritical cases. The arrays included 2x2xN, N = 2, 3, 4, and 5, in one program and 3x3x3 configurations in a later study. All were three-dimensional, nearly square arrays with equal horizontal lattice spacings but a different vertical lattice spacing. Horizontal spacings ranged from units in contact to 180 mm center-to-center; and vertical spacings ranged from about 80 mm to almost 400 mm center-to-center. Several nearly-equilateral 3x3x3 arrays exhibit an extremely sensitive dependence upon horizontal separation for identical vertical spacings. A line array of unreflected and essentially unmoderated canned plutonium metal units appeared to be well subcritical based on measurements made to assure safety during the manual assembly operations. All experiments were performed at two widely separated times in the mid-1970s and early 1980s under two programs at the Rocky Flats Plant`s Critical Mass Laboratory.

  5. The Use of Catalysts in Near-Critical Water Processing

    SciTech Connect (OSTI)

    Elliott, Douglas C.

    2005-06-26

    The use of heterogeneous catalysts in near-critical water processing provides many challenges of material stability in addition to the normal questions of chemical activity. Conventional catalyst materials developed in traditional organic chemistry or petroleum chemistry applications provide a source of information of materials with the required activities but often without the required stability when used in hot liquid water. The importance of the use of catalysts in near-critical water processing plays a particularly crucial role for the development of renewable fuels and chemicals based on biomass feedstocks. Stability issues include both those related to the catalytic metal and also to the catalyst support material. In fact, the stability of the support is the most likely concern when using conventional catalyst formulations in near-critical water processing. Processing test results are used to show important design parameters for catalyst formulations for use in wet biomass gasification in high-pressure water and in catalytic hydrogenations in water for production of value-added chemical products from biomass in the biorefinery concept. Analytical methods including powder x-ray diffraction for crystallite size and composition determination, surface area and porosity measurements, and elemental analysis have all been used to quantify differences in catalyst materials before and after use. By these methods both the chemical and physical stability of heterogeneous catalysts can be verified.

  6. Criticality Benchmark Analysis of Water-Reflected Uranium Oxyfluoride Slabs

    SciTech Connect (OSTI)

    Margaret A. Marshall; John D. Bess

    2009-11-01

    A series of twelve experiments were conducted in the mid 1950's at the Oak Ridge National Laboratory Critical Experiments Facility to determine the critical conditions of a semi-infinite water-reflected slab of aqueous uranium oxyfluoride (UO2F2). A different slab thickness was used for each experiment. Results from the twelve experiment recorded in the laboratory notebook were published in Reference 1. Seven of the twelve experiments were determined to be acceptable benchmark experiments for the inclusion in the International Handbook of Evaluated Criticality Safety Benchmark Experiments. This evaluation will not only be available to handbook users for the validation of computer codes and integral cross-section data, but also for the reevaluation of experimental data used in the ANSI/ANS-8.1 standard. This evaluation is important as part of the technical basis of the subcritical slab limits in ANSI/ANS-8.1. The original publication of the experimental results was used for the determination of bias and bias uncertainties for subcritical slab limits, as documented by Hugh Clark's paper 'Subcritical Limits for Uranium-235 Systems'.

  7. Critical Behavior in Light Nuclear Systems: Experimental Aspects

    E-Print Network [OSTI]

    Y. G. Ma; J. B. Natowitz; R. Wada; K. Hagel; J. Wang; T. Keutgen; Z. Majka; M. Murray; L. Qin; P. Smith; R. Alfaro; J. Cibor; M. Cinausero; Y. El Masri; D. Fabris; E. Fioretto; A. Keksis; M. Lunardon; A. Makeev; N. Marie; E. Martin; A. Martinez-Davalos; A. Menchaca-Rocha; G. Nebbia; G. Prete; V. Rizzi; A. Ruangma; D. V. Shetty; G. Souliotis; P. Staszel; M. Veselsky; G. Viesti; E. M. Winchester; S. J. Yennello

    2005-04-14

    An extensive experimental survey of the features of the disassembly of a small quasi-projectile system with $A \\sim$ 36, produced in the reactions of 47 MeV/nucleon $^{40}$Ar + $^{27}$Al, $^{48}$Ti and $^{58}$Ni, has been carried out. Nuclei in the excitation energy range of 1-9 MeV/u have been investigated employing a new method to reconstruct the quasi-projectile source. At an excitation energy $\\sim$ 5.6 MeV/nucleon many observables indicate the presence of maximal fluctuations in the de-excitation processes. The fragment topological structure shows that the rank sorted fragments obey Zipf's law at the point of largest fluctuations providing another indication of a liquid gas phase transition. The caloric curve for this system shows a monotonic increase of temperature with excitation energy and no apparent plateau. The temperature at the point of maximal fluctuations is $8.3 \\pm 0.5$ MeV. Taking this temperature as the critical temperature and employing the caloric curve information we have extracted the critical exponents $\\beta$, $\\gamma$ and $\\sigma$ from the data. Their values are also consistent with the values of the universality class of the liquid gas phase transition. Taken together, this body of evidence strongly suggests a phase change in an equilibrated mesoscopic system at, or extremely close to, the critical point.

  8. Smooth double critical state theory for type-II superconductors

    E-Print Network [OSTI]

    H. S. Ruiz; A. Bad\\'\\ia-Majós

    2010-05-30

    Several aspects of the general theory for the critical states of a vortex lattice and the magnetic flux dynamics in type-II superconductors are examined by a direct variational optimisation method and widespread physical principles. Our method allows to unify a number of conventional models describing the complex vortex configurations in the critical state regime. Special attention is given to the discussion of the relation between the flux-line cutting mechanism and the depinning threshold limitation. This is done by using a smooth double critical state concept which incorporates the so-called isotropic, elliptical, T and CT models as well-defined limits of our general treatment. Starting from different initial configurations for a superconducting slab in a 3D magnetic field, we show that the predictions of the theory range from the collapse to zero of transverse magnetic moments in the isotropic model, to nearly force free configurations in which paramagnetic values can arbitrarily increase with the applied field for magnetically anisotropic current voltage laws. Noteworthily, the differences between the several model predictions are minimal for the low applied field regime.

  9. High upper critical field in disordered niobium nitride superconductor

    SciTech Connect (OSTI)

    Baskaran, R., E-mail: baskaran@igcar.gov.in; Thanikai Arasu, A. V.; Amaladass, E. P.; Janawadkar, M. P. [Materials Science Group, IGCAR, Kalpakkam-603102 (India)

    2014-10-28

    Superconducting Niobium Nitride thin films have been deposited on glass, aluminum nitride buffered glass, and oxidized silicon substrates by reactive DC magnetron sputtering at ambient substrate temperatures. The crystal structure of these thin films has been determined to be cubic fcc B1 structure by Glancing Incidence X-Ray Diffraction analysis. The superconducting transition temperatures of the thin films were measured to be greater than 11.6?K with a maximum of 13.4?K. The negative temperature coefficient of resistance observed in these thin films indicates the presence of disorder. Magneto-resistance measurements have been carried out on these thin films patterned into standard four probe geometry upto a maximum magnetic field of 12?T for two films and upto 15?T for the other two films. The dependence of transition temperature on the applied field is analyzed to estimate the upper critical field. The upper critical field for most of the films was estimated to exceed 35?T, while one of the most disordered films had an estimated upper critical field greater than 70?T.

  10. Continuum Limits for Critical Percolation and Other Stochastic Geometric Models

    E-Print Network [OSTI]

    Michael Aizenman

    1998-06-06

    The talk presented at ICMP 97 focused on the scaling limits of critical percolation models, and some other systems whose salient features can be described by collections of random lines. In the scaling limit we keep track of features seen on the macroscopic scale, in situations where the short--distance scale at which the system's basic variables are defined is taken to zero. Among the challenging questions are the construction of the limit, and the explanation of some of the emergent properties, in particular the behavior under conformal maps as discussed in [LPS 94]. A descriptive account of the project, and some related open problems, is found in ref. [A] and in [AB] (joint work with A. Burchard) where tools are developed for establishing a curve--regularity condition which plays a key role in the construction of the limit. The formulation of the scaling limit as a random Web measure permits to formulate the question of uniqueness of measure(s) describing systems of random curves satisfying the conditions of independence, Euclidean invariance, and regularity. The uniqueness question remains open; progress on it could shed light on the purported universality of critical behavior and the apparent conformal invariance of the critical measures. The random Web yields also another perspective on some of the equations of conformal field theory which have appeared in this context, such as the equation proposed by J. Cardy [C].

  11. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    SciTech Connect (OSTI)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors.

  12. Helium- and Lithium-like ionic sequences: Critical charges

    E-Print Network [OSTI]

    N. L. Guevara; A. V. Turbiner

    2011-09-28

    In non-relativistic quantum mechanics we study the Coulomb systems of infinitely massive center of charge Z and two-three electrons: $(Z,e,e)$ and $(Z,e,e,e)$. It is shown that in both cases the total energy curve in $Z$ is smooth, without any visible irregularities. Thus, for both systems the physical integer charges $Z=1,2,...$ do not play a distinguished role as would be associated with charge quantization. By definition, a critical charge $Z_{cr}$ is a charge which separates a domain of the existence of bound states from a domain of unbound ones (continuum). For both systems the critical charges are found, $Z_{cr,2e}=0.91085$ and $Z_{cr,3e}=2.009$, respectively. Based on numerical analysis, the Puiseux expansion in fractional powers of $(Z-Z_{cr})$ is constructed for both systems. Our results indicate the existence of a square-root branch point singularity at $Z_{cr}$ with exponent 3/2. A connection between the critical charge and the radius of convergence of 1/Z-expansion is briefly discussed.

  13. Critical Oxidation Reactions Optimized with Solvent Swap | The...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    product with a high level of selectivity. Uncovering optimal conditions for widely-used chemical reactions is vital to creating technologically viable pathways for more...

  14. Parametric Multi-Level Tiling of Imperfectly Nested Loops

    SciTech Connect (OSTI)

    Hartono, Albert; Baskaran, Muthu M.; Bastoul, Cedric; Cohen, Albert; Krishnamoorthy, Sriram; Norris, Boyana; Ramanujam, J.; Sadayappan, Ponnuswamy

    2009-05-18

    Tiling is a critical loop transformation for generating high-performance code on modern architectures. Efficient generation of multilevel tiled code is essential to exploit several levels of parallelism and/or to maximize data reuse in deep memory hierarchies. Tiled loops with parameterized tile sizes (not compile time constants) facilitate runtime feedback and dynamic optimizations used in iterative compilation and automatic tuning. The existing parametric multilevel tiling approach has focused on transformation for perfectly nested loops, where all assignment statements are contained inside the innermost loop of a loop nest. Previous solutions to tiling for imperfect loop nests are limited to the case where tile sizes are fixed. In this paper, we present an approach to parameterized multilevel tiling for imperfectly nested loops. Our tiling algorithm generates loops that iterate over full rectangular tiles that are amenable for potential compiler optimizations such as register tiling. Experimental results using a number of computational benchmarks demonstrate the effectiveness of our tiling approach.

  15. Human exposure to mercury: A critical assessment of the evidence of adverse health effects

    SciTech Connect (OSTI)

    Ratcliffe, H.E.; Swanson, G.M.; Fischer, L.J. [Michigan State Univ., East Lansing, MI (United States)

    1996-10-25

    The ubiquitous nature of mercury in the environment, its global atmospheric cycling, and its toxicity to humans at levels that are uncomfortably close to exposures experienced by a proportion of the population are some of the current concerns associated with this pollutant. The purpose of this review is to critically evaluate the scientific quality of published reports involving human exposures to mercury and associated health outcomes as an aid in the risk evaluation of this chemical. A comprehensive review of the scientific literature involving human exposures to mercury was performed and each publication evaluated using a defined set of criteria that are considered standards in epidemiologic and toxicologic research. Severe, sometimes fatal, effects of mercury exposure at high levels were primarily reported as case studies. The disasters in Minamata, Japan, in the 1950s and in Iraq in 1971-1972 clearly demonstrated neurologic effects associated with ingestion of methylmercury both in adults and in infants exposed in utero. The effects were convincingly Associated with methylmercury ingestion, despite limitations of the study design. Several well-conducted studies have investigated the effects of methylmercury at levels below those in the Iraq incident but have not provided clear evidence of an effect. The lower end of the dose-response curve constructed from the Iraq data therefore still needs to be confirmed. The studies of mercury exposure in the workplace were mainly of elemental or inorganic mercury, and effects that were observed at relatively low exposure levels were primarily neurologic and renal. Several studies have investigated effects associated with dental amalgam but have been rated as inconclusive because of methodologic deficiencies. In our overall evaluation, 29 of 110 occupational studies and 20 of 54 studies where exposure occurred in the natural environment provided at least suggestive evidence of an exposure-related effect. 259 refs., 4 tabs.

  16. Vapor-like liquid coexistence densities affect the extension of the critical point's influence zone

    E-Print Network [OSTI]

    Rivera, Jose Luis; Guerra-Gonzalez, Roberto

    2015-01-01

    The critical point affects the coexistence behavior of the vapor-liquid equilibrium densities. The length of the critical influence zone is under debate because for some properties, like shear viscosity, the extension is only a few degrees, while for others, such as the density order parameter, the critical influence zone range covers up to hundreds of degrees below the critical temperature. Here we show that for a simple molecular potential of ethane, the critical influence zone covers a wide zone of tens of degrees (below the critical temperature) down to a transition temperature, at which the apparent critical influence zone vanishes and the transition temperature can be predicted through a pressure analysis of the coexisting bulk liquid phase. The liquid phases within the apparent critical influence zone show low densities, making them behave internally like their corresponding vapor phases. Therefore, the experimentally observed wide extension of the critical influence zone is due to a vapor-like effect ...

  17. Role of the H$_2^+$ channel in the primordial star formation under strong radiation field and the critical intensity for the supermassive star formation

    E-Print Network [OSTI]

    Sugimura, Kazuyuki; Omukai, Kazuyuki; Galli, Daniele; Palla, Francesco

    2015-01-01

    We investigate the role of the H_2^+ channel on H_2 molecule formation during the collapse of primordial gas clouds immersed in strong radiation fields which are assumed to have the shape of a diluted black-body spectra with temperature T_rad. Since the photodissociation rate of H_2^+ depends on its level population, we take full account of the vibrationally-resolved H_2^+ kinetics. We find that in clouds under soft but intense radiation fields with spectral temperature T_rad 7000 K, the H^- channel takes over H_2^+ in the production of molecular hydrogen. We calculate the critical radiation intensity needed for supermassive star formation by direct collapse and examine its dependence on the H_2^+ level population. Under the assumption of local thermodynamic equilibrium (LTE) level population, the critical intensity is underestimated by a factor of a few for soft spectra with T_rad < 7000 K. For harder spectra, the value of the critical intensity is not affected by the level population of H_2^+. This resu...

  18. The LHC Low Level RF

    E-Print Network [OSTI]

    Baudrenghien, Philippe; Molendijk, John Cornelis; Olsen, Ragnar; Rohlev, Anton; Rossi, Vittorio; Stellfeld, Donat; Valuch, Daniel; Wehrle, Urs

    2006-01-01

    The LHC RF consists of eight 400 MHz superconducting cavities per ring, with each cavity independently powered by a 300 kW klystron, via a circulator. The challenge for the Low Level is to cope with very high beam current (more than 1 A RF component) and achieve excellent beam lifetime (emittance growth time in excess of 25 hours). Each cavity has an associated Cavity Controller rack consisting of two VME crates which implement high gain RF Feedback, a Tuner Loop with a new algorithm, a Klystron Ripple Loop and a Conditioning system. In addition each ring has a Beam Control system (four VME crates) which includes a Frequency Program, Phase Loop, Radial Loop and Synchronization Loop. A Longitudinal Damper (dipole and quadrupole mode) acting via the 400 MHz cavities is included to reduce emittance blow-up due to filamentation from phase and energy errors at injection. Finally an RF Synchronization system implements the bunch into bucket transfer from the SPS into each LHC ring. When fully installed in 2007, the...

  19. New Resolved Resonance Region Evaluation for 63Cu and 65Cu for Nuclear Criticality Safety Program

    SciTech Connect (OSTI)

    Sobes, Vladimir; Leal, Luiz C; Guber, Klaus H; Forget, Benoit; Kopecky, S.; Schillebeeckx, P.; Siegler, P.

    2014-01-01

    A new resolved resonance region evaluation of 63Cu and 65Cu was done in the energy region from 10-5 eV to 99.5 keV. The R-Matrix SAMMY method using the Reich-Moore approximation was used to create a new set of consistent resonance parameters. The new evaluation was based on three experimental transmission data sets; two measured at ORELA and one from MITR, and two radiative capture experimental data sets from GELINA. A total of 141 new resonances were identied for 63Cu and 117 for 65Cu. The corresponding set of external resonances for each isotope was based on the identied resonances above 99.5 keV from the ORELA transmission data. The negative external levels (bound levels) were determined to match the dierential thermal cross section measured at the MITR. Double dierential elastic scattering cross sections were calculated from the new set of resonance parameters. Benchmarking calculations were carried out on a set of ICSBEP benchmarks. This work is in support of the DOE Nuclear Criticality Safety Program.

  20. CRITICAL RADIONUCLIDE AND PATHWAY ANALYSIS FOR THE SAVANNAH RIVER SITE

    SciTech Connect (OSTI)

    Jannik, T.

    2011-08-30

    This report is an update to the analysis, Assessment of SRS Radiological Liquid and Airborne Contaminants and Pathways, that was performed in 1997. An electronic version of this large original report is included in the attached CD to this report. During the operational history (1954 to the present) of the Savannah River Site (SRS), many different radionuclides have been released to the environment from the various production facilities. However, as will be shown by this updated radiological critical contaminant/critical pathway analysis, only a small number of the released radionuclides have been significant contributors to potential doses and risks to offsite people. The analysis covers radiological releases to the atmosphere and to surface waters, the principal media that carry contaminants offsite. These releases potentially result in exposure to offsite people. The groundwater monitoring performed at the site shows that an estimated 5 to 10% of SRS has been contaminated by radionuclides, no evidence exists from the extensive monitoring performed that groundwater contaminated with these constituents has migrated off the site (SRS 2011). Therefore, with the notable exception of radiological source terms originating from shallow surface water migration into site streams, onsite groundwater was not considered as a potential exposure pathway to offsite people. In addition, in response to the Department of Energy's (DOE) Order 435.1, several Performance Assessments (WSRC 2008; LWO 2009; SRR 2010; SRR 2011) and a Comprehensive SRS Composite Analysis (SRNO 2010) have recently been completed at SRS. The critical radionuclides and pathways identified in these extensive reports are discussed and, where applicable, included in this analysis.