National Library of Energy BETA

Sample records for unscheduled downtime due

  1. Unscheduled Downtime | The Ames Laboratory

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

    resources. ISU Telecommunications staff is aware of the issue. There is currently no time estimate for resolution. 81015 Solution: ISU telecom corrected the issue, the prolem...

  2. Nagios Down-Time scripts

    SciTech Connect (OSTI)

    Buddeberg, Patrick

    2014-11-11

    The Nagios Down-Time scripts are a set of Python scripts that create a commandline interface to Nagios' scheduled down-times. This allows for large-scale management of down-times, beyond what is feasible with the default web interface. Additionally, one of the scripts can be setup to periodically send emails of down-times that are scheduled to end within a specified amount of time after the script has been run; for example, it could run once a day and send an email including down-times ending within the next 24 hours.

  3. Nagios Down-Time scripts

    Energy Science and Technology Software Center (OSTI)

    2014-11-11

    The Nagios Down-Time scripts are a set of Python scripts that create a commandline interface to Nagios' scheduled down-times. This allows for large-scale management of down-times, beyond what is feasible with the default web interface. Additionally, one of the scripts can be setup to periodically send emails of down-times that are scheduled to end within a specified amount of time after the script has been run; for example, it could run once a day andmore » send an email including down-times ending within the next 24 hours.« less

  4. 2006 Update of Business Downtime Costs

    SciTech Connect (OSTI)

    Hinrichs, Mr. Doug; Goggin, Mr. Michael

    2007-01-01

    The objective of this paper is to assess the downtime cost of power outages to businesses in the commercial and industrial sectors, updating and improving upon studies that have already been published on this subject. The goal is to produce a study that, relative to existing studies, (1) applies to a wider set of business types (2) reflects more current downtime costs, (3) accounts for the time duration factor of power outages, and (4) includes data on the costs imposed by real outages in a well-defined market. This study examines power outage costs in 11 commercial subsectors and 5 industrial subsectors, using data on downtime costs that was collected in the 1990's. This study also assesses power outage costs for power outages of 20 minutes, 1 hour, and 4 hours duration. Finally, this study incorporates data on the costs of real power outages for two business subsectors. However, the current limited state of data availability on the topic of downtime costs means there is room to improve upon this study. Useful next steps would be to generate more recent data on downtime costs, data that covers outages shorter than 20 minutes duration and longer than 4 hours duration, and more data that is based on the costs caused by real-world outages. Nevertheless, with the limited data that is currently available, this study is able to generate a clear and detailed picture of the downtime costs that are faced by different types of businesses.

  5. Digital Twins of physical assets prevents unplanned downtime | GE Global

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

    Research a 'Digital Twin' for physical assets can help achieve no unplanned downtime Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) How a 'Digital Twin' for physical assets can help achieve no unplanned downtime Mark Grabb and Matt Nielsen, data scientists at GE Global Research, explain the importance of data

  6. Rotating machinery surveillance system reduces plant downtime and radiation exposure

    SciTech Connect (OSTI)

    Bohanick, J.S.; Robinson, J.C.; Allen, J.W.

    1988-01-01

    A rotating machinery surveillance system (RMSS) was permanently installed at Grand Gulf nuclear station (GGNS) as part of a program sponsored by the US Department of Energy whose goal was to reduce radiation exposure to power plant personnel resulting from the inspection, maintenance, and repair of rotating machinery. The RMSS was installed at GGNS in 1983 to continuously monitor 173 analog vibration signals from proximity probes mounted on 26 machine trains and {approximately}450 process data points via a computer data link. Vibration frequency spectra, i.e., the vibration amplitude versus frequency of vibration, and various characterizations of these spectra are the fundamental data collected by the RMSS for performing machinery diagnostics. The RMSS collects vibration frequency spectra on a daily basis for all the monitored rotating equipment and automatically stores the collected spectra for review by the vibration engineer. Vibration spectra automatically stored by the RMSS fall into categories that include the last normal, alarm, minimum and maximum, past three-day data set, baseline, current, and user-saved spectra. During first and second fuel-cycle operation at GGNS, several significant vibration problems were detected by the RMSS. Two of these are presented in this paper: recirculation pumps and turbine-generator bearing degradation. The total reduction in personnel radiation exposure at GGNS from 1985 to 1987 due to the presence of the RMSS was estimated to be in the range from 49 to 54 person-rem.

  7. Microsoft Word - NERSC_Results.doc

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

    ... Again, the scheduled software outage is the dominant source of downtime 1 . It is worth noting that power outages are comparable to the unscheduled software and hardware system ...

  8. SSRL BEAM PORT SCHEDULE

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

    5-1 Oct. 30, 2006 Oct. 31, 2006 Nov. 01, 2006 Nov. 02, 2006 Nov. 03, 2006 Nov. 04, 2006 Nov. 05, 2006 DOWN Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled Unscheduled BEAM LINE 5-2 Oct. 30, 2006 Oct. 31, 2006 Nov. 01, 2006 Nov. 02, 2006 Nov. 03, 2006 Nov. 04, 2006 Nov. 05, 2006 DOWN Unscheduled Unscheduled Unscheduled

  9. Digital Twins of physical assets prevents unplanned downtime...

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

    materials, software, and analytics to commercialization, process, and business model best practices. The GE Store allows GE to leapfrog industries, to drive innovation,...

  10. IR keeps coal miners safe and reduces downtime

    SciTech Connect (OSTI)

    Massey, L.G.

    2009-01-15

    Infrared (IR) cameras can inspect the direct current trolley system that powers mantrips and locomotives that transport men and supplies to an underground mine. If trolley insulators become shorted or electrically leaky they can heat the roof and cause a fire or cave-in. The article explains how IR inspection works and describes typical problems that can be identified by thermograms. 8 figs.

  11. Precision welding cuts downtime at Grand Coulee Dam

    SciTech Connect (OSTI)

    Light, S.; White, E.

    1997-03-01

    The three large 700-MW generators at Grand Coulee Dam--originally built and installed by Canadian General Electric in the late 1970s--are being upgraded using precision welding techniques and leading edge installation technology. These generators suffered from numerous water leaks at and around the bar water connections, resulting in a significant number of forced repair outages that were increasing in frequency. The US Bureau of Reclamation, in conjunction with the Bonneville Power Administration, decided to overhaul these machines. The design from Siemens Power Corp. provided state-of-the-art materials and included a rating increase from 700 to 805 MW, which would make these three machines the highest output single-unit hydrogenerators in the world. The upgrade was to be accomplished with only the replacement of the stator components; there would be no changes to the rotating element. The cost for all three machines is approximately $27.5 million. This project is described in this paper.

  12. NISE Requests Due Feb. 24

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

    NISE Requests Due Feb. 24 NISE Requests Due Feb. 24 January 1, 2011 by Francesca Verdier The first round of NERSC Initiative for Scientific Exploration (NISE) requests are due February 24. Ten percent of NERSC time is allocated through this program. See NERSC Initiative for Scientific Exploration. Subscribe via RSS Subscribe Browse by Date August 2016 June 2016 May 2016 April 2016 January 2016 December 2015 November 2015 October 2015 September 2015 August 2015 July 2015 April 2015 March 2015

  13. Inductance due to spin current

    SciTech Connect (OSTI)

    Chen, Wei

    2014-03-21

    The inductance of spintronic devices that transport charge neutral spin currents is discussed. It is known that in a media that contains charge neutral spins, a time-varying electric field induces a spin current. We show that since the spin current itself produces an electric field, this implies existence of inductance and electromotive force when the spin current changes with time. The relations between the electromotive force and the corresponding flux, which is a vector calculated by the cross product of electric field and the trajectory of the device, are clarified. The relativistic origin generally renders an extremely small inductance, which indicates the advantage of spin current in building low inductance devices. The same argument also explains the inductance due to electric dipole current and applies to physical dipoles consist of polarized bound charges.

  14. 2012 NERSC allocation requests due September 23

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

    2 NERSC allocation requests due September 23 2012 NERSC allocation requests due September 23 August 17, 2011 by Francesca Verdier The ERCAP allocation submission system is now open...

  15. 2015 NERSC allocation requests due September 22

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

    requests due September 22 2015 NERSC allocation requests due September 22 August 13, 2014 by Francesca Verdier The NERSC allocation submission system is now open for 2015 requests. ...

  16. 2014 DOE ALCC Proposals Due February 3

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

    ALCC Proposals Due February 3, 2014 2014 DOE ALCC Proposals Due February 3 December 23, 2013 by Francesca Verdier DOE's 2014 call for its ASCR Leadership Computing Challenge (ALCC) competition is posted: http://science.energy.gov/ascr/facilities/alcc/. There are new guidelines this year: http://science.energy.gov/ascr/facilities/alcc/alcc-application-details/. Proposals for 2014 ALCC are due 11:59 PM EST February 3rd, 2014. Email your completed proposal to ALCC@science.doe.gov. PDF format is

  17. 2014 DOE ALCC Proposals Due February 3

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

    There are new guidelines this year: http:science.energy.govascrfacilitiesalccalcc-application-details. Proposals for 2014 ALCC are due 11:59 PM EST February 3rd, 2014. Email ...

  18. Fourth Friday Cancelled due to Thanksgiving Holidays

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

    open late until 6:00 PM offering access to exhibits and special activities for all ages, however it will not take place on Friday, November 27 due to the Thanksgiving...

  19. Visualization Contest Applications due August 3

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

    Contest Applications due August 3 June 22, 2012 by Francesca Verdier In support of the IEEE Symposium on Large-Scale Data Analysis and Visualization (LDAV) 2012's visualization...

  20. Visualization Contest Applications due August 3

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

    Visualization Contest Applications due August 3 Visualization Contest Applications due August 3 June 22, 2012 by Francesca Verdier In support of the IEEE Symposium on Large-Scale Data Analysis and Visualization (LDAV) 2012's visualization contest, LDAV organizers are offering compute time to participants through a NERSC allocation awarded by ASCR. The LDAV Visualization Contest focuses on the area of visualization of extremely large datasets. The goal is to devise a visualization or a

  1. Applications for ACTS Workshop Due June 24

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

    for ACTS Workshop Due June 24 Applications for ACTS Workshop Due June 24 June 1, 2012 by Francesca Verdier The 13th Workshop on the DOE Advanced Computational Software (ACTS) Collection, Scalable and Robust Computational Libraries and Tools for High-End Computing, will be held in Berkeley, CA, on August 14-17, 2012.ide range of applications and fields in computational sciences. The four-day workshop will include tutorials on the tools currently available in the collection, discussion sessions to

  2. 2012 NERSC allocation requests due September 23

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

    2 NERSC allocation requests due September 23 2012 NERSC allocation requests due September 23 August 17, 2011 by Francesca Verdier The ERCAP allocation submission system is now open for 2012 NERSC allocation requests. All current projects (including startup, education, and ALCC projects) must be renewed for 2012 if you wish to continue using NERSC. New project requests may be submitted as well (for either the remainder of 2011 or for 2012). The deadline for 2012 requests is September 23, 2011.

  3. 2013 Allocation Request Submissions Due September 28

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

    3 Allocation Request Submissions Due September 28 2013 Allocation Request Submissions Due September 28 August 1, 2012 by Francesca Verdier The deadline for submissions for 2013 NERSC allocation requests is September 28 at 11:59 p.m. PDT. All current 2012 NERSC projects (including startup, education, ALCC, NISE and Data Intensive Pilot projects) must be renewed for 2013 in order to continue using NERSC. Award decisions for requests submitted before this deadline will be emailed to Principal

  4. 2013 INCITE Proposals due June 27

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

    INCITE Proposals 2013 INCITE Proposals due June 27 June 15, 2012 by Francesca Verdier The Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program promotes transformational advances in science and technology through large allocations of computer time, supporting resources, and data storage at the Argonne and Oak Ridge Leadership Computing Facilities. 2013 proposals are due June 27. See 2013 INCITE Call for Proposals. Subscribe via RSS Subscribe Browse by Date August

  5. 2014 NERSC allocation requests due September 22

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

    allocation requests due September 22 2014 NERSC allocation requests due September 22 August 13, 2013 by Francesca Verdier NERSC's allocation submission system is now open for 2014 allocation requests. All current projects (including startup, education, and ALCC projects) must be renewed for 2014 if you wish to continue using NERSC. New project requests may be submitted as well (for either the remainder of 2013 or for 2014). The deadline for 2014 requests is 23:59 PM September 22, 2013. Award

  6. Renewable Energy Loan Applications Due Today!

    Broader source: Energy.gov [DOE]

    If you haven't submitted your Part I application for Department of Energy Loan Guarantee Program’s Renewables Solicitation yet, today is your last day! Round 8, Part I applications for DOE's Energy Efficiency, Renewable Energy and Advanced Transmission and Distribution Technologies Solicitation (2009) are due today by midnight EDT.

  7. Constrained inflaton due to a complex scalar

    SciTech Connect (OSTI)

    Budhi, Romy H. S.; Kashiwase, Shoichi; Suematsu, Daijiro

    2015-09-14

    We reexamine inflation due to a constrained inflaton in the model of a complex scalar. Inflaton evolves along a spiral-like valley of special scalar potential in the scalar field space just like single field inflation. Sub-Planckian inflaton can induce sufficient e-foldings because of a long slow-roll path. In a special limit, the scalar spectral index and the tensor-to-scalar ratio has equivalent expressions to the inflation with monomial potential φ{sup n}. The favorable values for them could be obtained by varying parameters in the potential. This model could be embedded in a certain radiative neutrino mass model.

  8. Particle transport due to magnetic fluctuations

    SciTech Connect (OSTI)

    Stoneking, M.R.; Hokin, S.A.; Prager, S.C.; Fiksel, G.; Ji, H.; Den Hartog, D.J.

    1994-01-01

    Electron current fluctuations are measured with an electrostatic energy analyzer at the edge of the MST reversed-field pinch plasma. The radial flux of fast electrons (E>T{sub e}) due to parallel streaming along a fluctuating magnetic field is determined locally by measuring the correlated product <{tilde J}{sub e}{tilde B}{sub r}>. Particle transport is small just inside the last closed flux surface ({Gamma}{sub e,mag} < 0.1 {Gamma}{sub e,total}), but can account for all observed particle losses inside r/a=0.8. Electron diffusion is found to increase with parallel velocity, as expected for diffusion in a region of field stochasticity.

  9. Alpha particles diffusion due to charge changes

    SciTech Connect (OSTI)

    Clauser, C. F. Farengo, R.

    2015-12-15

    Alpha particles diffusion due to charge changes in a magnetized plasma is studied. Analytical calculations and numerical simulations are employed to show that this process can be very important in the pedestal-edge-SOL regions. This is the first study that presents clear evidence of the importance of atomic processes on the diffusion of alpha particles. A simple 1D model that includes inelastic collisions with plasma species, “cold” neutrals, and partially ionized species was employed. The code, which follows the exact particle orbits and includes the effect of inelastic collisions via a Monte Carlo type random process, runs on a graphic processor unit (GPU). The analytical and numerical results show excellent agreement when a uniform background (plasma and cold species) is assumed. The simulations also show that the gradients in the density of the plasma and cold species, which are large and opposite in the edge region, produce an inward flux of alpha particles. Calculations of the alpha particles flux reaching the walls or divertor plates should include these processes.

  10. Cable twisting due to atmospheric icing

    SciTech Connect (OSTI)

    McComber, P.; Druez, J.; Savadjiev, K.

    1995-12-31

    Samples of ice accretions collected on cables of overhead transmission lines have shown evidence of twisting of the cable during atmospheric icing. Previous work has attributed cable twisting to the torque created by the weight of an eccentric ice shape and by wind forces. However, testing of stranded cables and conductors has shown that such cables also twist when there is a change in tension in the cable span. This phenomenon is related to the interaction of the different strand layers under tension. When a cable is subjected to atmospheric icing, cable tension increases and this type of twisting should also be considered. In order to determine how the two types of twisting would compare on transmission lines, a numerical simulation was made using characteristics of a typical 35-mm stranded conductor. The twist angle was computed as a function of cable span, sag to span ratio and increasing ice loads. The simulation shows that for transmission lines, twisting due to varying tension will be significant. Since cable tension is influenced by wind speed and ambient temperature as well as ice load, this phenomenon, unless prevented, results in ice accretion more circular in shape and hence eventually in larger ice loads.

  11. Preventive maintenance system for the photomultiplier detector blocks of pet scanners

    DOE Patents [OSTI]

    Levy, Alejandro V.; Warner, Donald

    1995-01-24

    A system including a method and apparatus for preventive maintenance of PET scanner photomultiplier detector blocks is disclosed. The quantitive comparisons used in the method of the present invention to provide an indication in the form of a display or printout advising the user that the photomultiplier block is stable, intermittently unstable, or drifting unstable, and also advising of the expected date of failure of a photomultiplier block in the PET scanner. The system alerts the user to replace the defective photomultiplier block prior to catastrophic failure in a scheduled preventative maintenance program, thus eliminating expensive and unscheduled downtime of the PET scanner due to photomultiplier failure. The apparatus for carrying out the method of the present invention preferably resides in the host computer controlling a PET scanner. It includes a memory adapted for storing a record of a number of iterative adjustments that are necessary to calibrate the gain of a photomultiplier detector block i at a time t.sub.0, a time t.sub.1 and a time T, where T>t.sub.1 >t.sub.0, which is designated as Histo(i,j(t)). The apparatus also includes a processor configured by a software program or a combination of programmed RAM and ROM devices to perform a number of calculations and operations on these values, and also includes a counter for analyzing each photomultiplier detector block i=1 through I of a PET scanner.

  12. Preventive maintenance system for the photomultiplier detector blocks of PET scanners

    DOE Patents [OSTI]

    Levy, A.V.; Warner, D.

    1995-01-24

    A system including a method and apparatus for preventive maintenance of PET scanner photomultiplier detector blocks is disclosed. The qualitative comparisons used in the method of the present invention to provide an indication in the form of a display or printout advising the user that the photomultiplier block is stable, intermittently unstable, or drifting unstable, and also advising of the expected date of failure of a photomultiplier block in the PET scanner. The system alerts the user to replace the defective photomultiplier block prior to catastrophic failure in a scheduled preventative maintenance program, thus eliminating expensive and unscheduled downtime of the PET scanner due to photomultiplier failure. The apparatus for carrying out the method of the present invention preferably resides in the host computer controlling a PET scanner. It includes a memory adapted for storing a record of a number of iterative adjustments that are necessary to calibrate the gain of a photomultiplier detector block i at a time t[sub 0], a time t[sub 1] and a time T, where T>t[sub 1]>t[sub 0], which is designated as Histo(i,j(t)). The apparatus also includes a processor configured by a software program or a combination of programmed RAM and ROM devices to perform a number of calculations and operations on these values, and also includes a counter for analyzing each photomultiplier detector block i=1 through I of a PET scanner. 40 figures.

  13. Adv. Fossil Solicitation Part I Due Date | Department of Energy

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

    Fossil Solicitation Part I Due Date Adv. Fossil Solicitation Part I Due Date January 13, 2016 12:01AM to 11:59PM EST ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART I DUE DATE ...

  14. Adv. Nuclear Solicitation Part I Due Date | Department of Energy

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

    Nuclear Solicitation Part I Due Date Adv. Nuclear Solicitation Part I Due Date March 16, 2016 12:01AM to 11:59PM EDT ADVANCED NUCLEAR ENERGY PROJECTS SOLICITATION PART I DUE DATE ...

  15. REEE Solicitation Part I Due Date | Department of Energy

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

    I Due Date REEE Solicitation Part I Due Date November 30, 2016 1:01AM EST to December 1, 2016 12:59AM EST RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART I DUE DATE

  16. REEE Solicitation Part II Due Date | Department of Energy

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

    II Due Date REEE Solicitation Part II Due Date November 30, 2016 1:01AM EST to December 1, 2016 12:59AM EST RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART II DUE DATE

  17. REEE Solicitation Part II Due Date | Department of Energy

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

    REEE Solicitation Part II Due Date REEE Solicitation Part II Due Date April 13, 2016 12:01AM to 11:59PM EDT RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART II DUE...

  18. REEE Solicitation Part I Due Date | Department of Energy

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

    I Due Date REEE Solicitation Part I Due Date March 16, 2016 12:01AM to 11:59PM EDT RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART I DUE DATE...

  19. REEE Solicitation Part II Due Date | Department of Energy

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

    REEE Solicitation Part II Due Date REEE Solicitation Part II Due Date June 15, 2016 12:01AM to 11:59PM EDT RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART II DUE...

  20. Adv. Fossil Solicitation Part I Due Date | Department of Energy

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

    Fossil Solicitation Part I Due Date Adv. Fossil Solicitation Part I Due Date March 16, 2016 12:01PM to 11:59PM EDT ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART I DUE DATE...

  1. REEE Solicitation Part I Due Date | Department of Energy

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

    I Due Date REEE Solicitation Part I Due Date September 14, 2016 12:01AM to 11:59PM EDT RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART I DUE DATE

  2. Adv. Nuclear Solicitation Part I Due Date | Department of Energy

    Energy Savers [EERE]

    Nuclear Solicitation Part I Due Date Adv. Nuclear Solicitation Part I Due Date July 20, 2016 12:01AM to 11:59PM EDT ADVANCED NUCLEAR ENERGY PROJECTS SOLICITATION PART I DUE DATE ...

  3. Study forecasts disappearance of conifers due to climate change

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

    Study forecasts disappearance of conifers due to climate change Study forecasts disappearance of conifers due to climate change New results, reported in a paper released today in ...

  4. Anisoplanatism in adaptive optics systems due to pupil aberrations...

    Office of Scientific and Technical Information (OSTI)

    Anisoplanatism in adaptive optics systems due to pupil aberrations Citation Details In-Document Search Title: Anisoplanatism in adaptive optics systems due to pupil aberrations You ...

  5. Potential for radionuclide redistribution due to biotic intrusion...

    Office of Scientific and Technical Information (OSTI)

    Potential for radionuclide redistribution due to biotic intrusion: Aboveground biomass ... due to biotic intrusion: Aboveground biomass study at the Los Alamos National ...

  6. Anisoplanatism in adaptive optics systems due to pupil aberrations...

    Office of Scientific and Technical Information (OSTI)

    Conference: Anisoplanatism in adaptive optics systems due to pupil aberrations Citation Details In-Document Search Title: Anisoplanatism in adaptive optics systems due to pupil ...

  7. Adv. Nuclear Solicitation Part II Due Date | Department of Energy

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

    Adv. Nuclear Solicitation Part II Due Date Adv. Nuclear Solicitation Part II Due Date April 13, 2016 12:01AM to 11:59PM EDT ADVANCED NUCLEAR ENERGY PROJECTS SOLICITATION PART II ...

  8. NERSC Initiative for Scientific Exploration proposals due May...

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

    proposals due May 31 NERSC Initiative for Scientific Exploration proposals due May 31 May 2, 2011 by Francesca Verdier The deadline to apply for the second and final round of award...

  9. SC11 Education Program Applications due July 31

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

    SC11 Education Program Applications due July 31 SC11 Education Program Applications due July 31 June 9, 2011 by Francesca Verdier Applications for the Education Program are now ...

  10. Adv. Fossil Solicitation Part I Due Date | Department of Energy

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

    I Due Date Adv. Fossil Solicitation Part I Due Date November 30, 2016 1:01AM EST to December 1, 2016 12:59AM EST ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART I

  11. Adv. Fossil Solicitation Part II Due Date | Department of Energy

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

    II Due Date Adv. Fossil Solicitation Part II Due Date November 30, 2016 1:01AM AST to December 1, 2016 12:59AM AST ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART II

  12. Adv. Fossil Solicitation Part I Due Date | Department of Energy

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

    Fossil Solicitation Part I Due Date Adv. Fossil Solicitation Part I Due Date September 14, 2016 12:01AM to 11:59PM EDT ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART I DUE DATE Learn more about the Advanced Fossil

  13. Adv. Nuclear Solicitation Part II Due Date | Department of Energy

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

    Nuclear Solicitation Part II Due Date Adv. Nuclear Solicitation Part II Due Date November 23, 2016 12:01AM to 11:59PM EST ADVANCED NUCLEAR ENERGY PROJECTS SOLICITATION PART II DUE DATE Learn more about the Advanced Nuclear

  14. Adv. Nuclear Solicitation Part II Due Date | Department of Energy

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

    Nuclear Solicitation Part II Due Date Adv. Nuclear Solicitation Part II Due Date October 19, 2016 12:01AM to 11:59PM EDT ADVANCED NUCLEAR ENERGY PROJECTS SOLICITATION PART II DUE DATE Learn more about the Advanced Nuclear

  15. Wind Turbine Drivetrain Condition Monitoring - An Overview (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.; Yang, W.

    2013-07-01

    High operation and maintenance costs still hamper the development of the wind industry despite its quick growth worldwide. To reduce unscheduled downtime and avoid catastrophic failures of wind turbines and their components have been and will be crucial to further raise the competitiveness of wind power. Condition monitoring is one of the key tools for achieving such a goal. To enhance the research and development of advanced condition monitoring techniques dedicated to wind turbines, we present an overview of wind turbine condition monitoring, discuss current practices, point out existing challenges, and suggest possible solutions.

  16. Acquisition Letter on Allowability of Incurred Costs Due to Contractor

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

    Errors | Department of Energy on Allowability of Incurred Costs Due to Contractor Errors Acquisition Letter on Allowability of Incurred Costs Due to Contractor Errors The attached Acquisition Letter has been issued to provide application guidance to contracting officers for determining the allowability of incurred costs due to contractor errors. It applies to all contracts, including management and operating contracts, whose price or cost reimbursement is based on estimated or incurred

  17. ASCR Leadership Computing Challenge (ALCC) proposals due February...

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

    Proposals are due February 1, 2013. See: http:science.energy.govascrfacilitiesalcc. Subscribe via RSS Subscribe Browse by Date April 2016 January 2016 December 2015 November ...

  18. Sandia National Laboratories: Due Diligence on Lead Acid Battery...

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

    Due Diligence on Lead Acid Battery Recycling March 23, 2011 Lead Acid Batteries on secondary containment pallet Lead Acid Batteries on secondary containment pallet In 2004, the US...

  19. EAC Meeting Cancelled Due to Weather | Department of Energy

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

    Cancelled Due to Weather EAC Meeting Cancelled Due to Weather March 5, 2013 - 3:06pm Addthis This week's Electricity Advisory Committee (EAC) meeting has been cancelled due to a strong winter storm which is predicted to impact the Washington DC area on Wednesday. Originally scheduled to be held March 6 and March 7 in Arlington, Virginia, the EAC meeting may possibly be rescheduled for a later date. If the meeting is rescheduled, details will be posted online and will be published in a new

  20. COLLATERAL EFFECTS ON SOLAR NEBULA OXYGEN ISOTOPES DUE TO INJECTION...

    Office of Scientific and Technical Information (OSTI)

    COLLATERAL EFFECTS ON SOLAR NEBULA OXYGEN ISOTOPES DUE TO INJECTION OF sup 26Al BY A NEARBY SUPERNOVA Citation Details In-Document Search Title: COLLATERAL EFFECTS ON SOLAR ...

  1. REEE Solicitation Part II Due Date | Department of Energy

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

    12:01AM to 11:59PM EST RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART II DUE DATE Learn more about the Renewable Energy and Efficent Energy Projects Solicitation...

  2. Adv. Fossil Solicitation Part II Due Date | Department of Energy

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

    January 29, 2016 12:01AM to 11:59PM EST ADVANCED FOSSIL ENERGY PROJECTS SOLICITATION PART II DUE DATE Learn more about the Advanced Fossil Energy Projects Solicitation...

  3. REEE Solicitation Part II Due Date | Department of Energy

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

    12:01AM to 11:59PM EDT RENEWABLE ENERGY AND EFFICENT ENERGY PROJECTS SOLICITATION PART II DUE DATE Learn more about the Renewable Energy and Efficent Energy Projects...

  4. ASCR Leadership Computing Challenge (ALCC) proposals due February 1, 2013

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

    (ALCC) proposals due February 1, 2013 ASCR Leadership Computing Challenge (ALCC) proposals due February 1, 2013 January 2, 2013 by Francesca Verdier DOE's ASCR Leadership Computing Challenge (ALCC) program is intended for special situations of interest to the Department's energy mission, with an emphasis on high-risk, high-payoff simulations: Advancing the clean energy agenda. Advancing a robust predictive understanding of the Earth's climate and environmental systems. Responding to natural and

  5. ASCR Leadership Computing Challenge Requests for Time Due February 14

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

    Requests for Time Due February 14 ASCR Leadership Computing Challenge Requests for Time Due February 14 November 17, 2011 by Francesca Verdier The ASCR Leadership Computing Challenge (ALCC) program is open to scientists from the research community in national laboratories, academia and industry. This program allocates time at NERSC and the Leadership Computing Facilities at Argonne and Oak Ridge. Areas of interest are: Advancing the clean energy agenda. Understanding the environmental impacts of

  6. ASCR Leadership Computing Challenge proposals due February 3

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

    proposals due February 3 ASCR Leadership Computing Challenge proposals due February 3 January 6, 2015 by Francesca Verdier The Call for 2015 ALCC is now open. See http://science.energy.gov/ascr/facilities/alcc/ for details. ALCC supports projects that advance the DOE mission and further the goals of DOE program offices. For 2015 ALCC, projects of special interest to the DOE include the following: Energy efficiency and the clean energy agenda Nuclear reactor safety and environmental management of

  7. NERSC Initiative for Scientific Exploration proposals due May 31

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

    proposals due May 31 NERSC Initiative for Scientific Exploration proposals due May 31 May 2, 2011 by Francesca Verdier The deadline to apply for the second and final round of award decisions for the NERSC Initiative for Scientific Exploration (NISE) program is May 31, 2011. Award decisions will be announced by mid June. Details of NISE award and application form can be found at: NERSC Initiative for Scientific Exploration (NISE) Subscribe via RSS Subscribe Browse by Date August 2016 June 2016

  8. Technology Solutions Case Study: Overcoming Comfort Issues Due to Reduced

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

    Flow Room Air Mixing | Department of Energy Case Study: Overcoming Comfort Issues Due to Reduced Flow Room Air Mixing Technology Solutions Case Study: Overcoming Comfort Issues Due to Reduced Flow Room Air Mixing Energy efficiency upgrades reduce heating and cooling loads on a house. With enough load reduction and if the heating, ventilating, and air-conditioning (HVAC) system warrants replacement, the HVAC system is often upgraded with a more efficient, lower capacity system that meets the

  9. SC11 Education Program Applications due July 31

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

    SC11 Education Program Applications due July 31 SC11 Education Program Applications due July 31 June 9, 2011 by Francesca Verdier Applications for the Education Program are now being accepted. Submission website: https://submissions.supercomputing.org Applications deadline: Sunday, July 31, 2011 Acceptance Notifications: Monday, August 22, 2011 The Education Program is hosting a four-day intensive program that will immerse participants in High Performance Computing (HPC) and Computational and

  10. Los Alamos STEM Challenge registration due April 12

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

    Los Alamos STEM Challenge registration due April 12 Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Los Alamos STEM Challenge registration due April 12 Submission deadline April 30. April 1, 2013 Two students at work on a laptop Videos, posters, apps and essays are all possible submissions for the upcoming STEM Challenge for students. Contact Editor Linda Anderman Email Community

  11. Study forecasts disappearance of conifers due to climate change

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

    Study forecasts disappearance of conifers due to climate change Study forecasts disappearance of conifers due to climate change New results, reported in a paper released today in the journal Nature Climate Change, suggest that global models may underestimate predictions of forest death. December 21, 2015 Los Alamos scientist Nate McDowell discusses how climate change is killing trees with PBS NewsHour reporter Miles O'Brien. Los Alamos scientist Nate McDowell discusses how climate change is

  12. Summer 2012 National Geothermal Academy: Applications Due February 15 |

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

    Department of Energy Summer 2012 National Geothermal Academy: Applications Due February 15 Summer 2012 National Geothermal Academy: Applications Due February 15 January 23, 2012 - 4:02pm Addthis Course modules run from June 18 to August 10. (Download Application) The National Geothermal Academy is proud to present an intensive summer course in all aspects of geothermal energy development and utilization, held at the University of Nevada, Reno campus. The eight-week course is offered for

  13. Protecting the Electric Grid from Increasingly Severe Weather Due to

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

    Climate Change | Department of Energy Electric Grid from Increasingly Severe Weather Due to Climate Change Protecting the Electric Grid from Increasingly Severe Weather Due to Climate Change August 12, 2013 - 5:25pm Addthis Transmission lines along Highway 15 outside Victorville, California. | Photo courtesy of Abby Rowling. Transmission lines along Highway 15 outside Victorville, California. | Photo courtesy of Abby Rowling. Patricia A. Hoffman Patricia A. Hoffman Assistant Secretary,

  14. AY 2016 ERCAP Renewals Due Sept 21st

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

    AY 2016 ERCAP Renewals Due Sept 21st AY 2016 ERCAP Renewals Due Sept 21st September 18, 2015 Rememeber to submit your AY 2016 ERCAP renewal requests by 21:59 on Monday Sept. 21st. Thanks. Subscribe via RSS Subscribe Browse by Date August 2016 June 2016 May 2016 April 2016 January 2016 December 2015 November 2015 October 2015 September 2015 August 2015 July 2015 April 2015 March 2015 January 2015 December 2014 November 2014 October 2014 August 2014 June 2014 May 2014 April 2014 March 2014 January

  15. Rising Sea Levels Due to Global Warming Are Unstoppable

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

    Rising Sea Levels Due to Global Warming Are Unstoppable Rising Sea Levels Due to Global Warming Are Unstoppable Mitigation can slow down but not prevent sea level rise for centuries to come August 5, 2013 Contact: Linda Vu, Lvu@lbl.gov, +1 510 495 2402 washington.jpg Because seawater absorbs heat more slowly than the atmosphere above it, our oceans won't feel the full impact of the greenhouse gases already in the air for hundreds of years. Warm water expands, raising sea levels. (Courtesy W.

  16. Sandia National Laboratories: Due Diligence on Lead Acid Battery Recycling

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

    Due Diligence on Lead Acid Battery Recycling March 23, 2011 Lead Acid Batteries on secondary containment pallet Lead Acid Batteries on secondary containment pallet In 2004, the US Geological Survey estimated that 95% of lead in the United States is recycled, primarily from used lead acid batteries. A broader 2009 European study estimated that globally about 52% of lead is recycled, and a 2008 Asian study estimated a global recycle rate of 68%. Unfortunately, many incidents over the past decade

  17. Charge Transport Anisotropy Due to Grain Boundaries in Directionally

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

    Crystallized Thin Films of Regio-Regular Poly(3-hexylthiophene) Charge Transport Anisotropy Due to Grain Boundaries in Directionally Crystallized Thin Films of Regio-Regular Poly(3-hexylthiophene) Semicrystalline polymers, such as polythiophenes, hold much promise as active layers in printable electronic devices such as photovoltaic cells, sensors, and thin film transistors. As organic semiconductors approach commercialization, there is a need to better understand the relationship between

  18. Failure Forewarning in NPP Equipment NERI2000-109 Final Project Report

    SciTech Connect (OSTI)

    Hively, LM

    2004-03-26

    The objective of this project is forewarning of machine failures in critical equipment at next-generation nuclear power plants (NPP). Test data were provided by two collaborating institutions: Duke Engineering and Services (first project year), and the Pennsylvania State University (Applied Research Laboratory) during the second and third project years. New nonlinear methods were developed and applied successfully to extract forewarning trends from process-indicative, time-serial data for timely, condition-based maintenance. Anticipation of failures in critical equipment at next-generation NPP will improve the scheduling of maintenance activities to minimize safety concerns, unscheduled non-productive downtime, and collateral damage due to unexpected failures. This approach provides significant economic benefit, and is expected to improve public acceptance of nuclear power. The approach is a multi-tiered, model-independent, and data-driven analysis that uses ORNL's novel nonlinear method to extract forewarning of machine failures from appropriate data. The first tier of the analysis provides a robust choice for the process-indicative data. The second tier rejects data of inadequate quality. The third tier removes signal artifacts that would otherwise confound the analysis, while retaining the relevant nonlinear dynamics. The fourth tier converts the artifact-filtered time-serial data into a geometric representation, that is then transformed to a discrete distribution function (DF). This method allows for noisy, finite-length datasets. The fifth tier obtains dissimilarity measures (DM) between the nominal-state DF and subsequent test-state DFs. Forewarning of a machine failure is indicated by several successive occurrences of the DM above a threshold, or by a statistically significant trend in the DM. This paradigm yields robust nonlinear signatures of degradation and its progression, allowing earlier and more accurate detection of the machine failure.

  19. EXCITATION OF STRUCTURAL RESONANCE DUE TO A BEARING FAILURE

    SciTech Connect (OSTI)

    Leishear, R; David Stefanko, D

    2007-04-30

    Vibration due to a bearing failure in a pump created significant vibrations in a fifteen foot by fifteen foot by eight feet tall mounting platform due to excitation of resonant frequencies. In this particular application, an 18,000 pound pump was mounted to a structural steel platform. When bearing damage commenced, the platform vibrated with sufficient magnitude that conversations could not be heard within forty feet of the pump. Vibration analysis determined that the frequency of the bearing was coincident to one of the natural frequencies of the pump, which was, in turn, coincident to one of the natural frequencies of the mounting platform. This coincidence of frequencies defines resonance. Resonance creates excessive vibrations when the natural frequency of a structure is coincident to an excitation frequency. In this well documented case, the excitation frequency was related to ball bearing failures. The pump is a forty foot long vertical pump used to mix nuclear waste in 1,300,000 gallon tanks. A 300 horsepower drive motor is mounted to a structural steel platform on top of the tank. The pump hangs down into the tank from above to mix the waste and is inaccessible after installation. Initial awareness of the problem was due to increased noise from the pump. Initial vibration analysis indicated that the vibration levels of the bearing were within the expected range for this type of bearing, and the resonant condition was not obvious. Further analysis consisted of disassembly of the motor to inspect the bearings and extensive vibration monitoring. Vibration data for the bearings was obtained from the manufacturer and compared to measured vibration plots for the pump and mounting platform. Vibration data measured along the length of the pump was available from full scale testing, and vibrations were also measured at the installed pump. One of the axial frequencies of the pump, the platform frequency in the vertical direction, and the ball spin frequency for the

  20. Optical loss due to diffraction by concentrator Fresnel lenses

    SciTech Connect (OSTI)

    Hornung, Thorsten Nitz, Peter

    2014-09-26

    Fresnel lenses are widely used in concentrating photovoltaic (CPV) systems as a primary optical element. They focus sunlight on small solar cells or on the entrance apertures of secondary optical elements. A Fresnel lens consists of several prism rings and diffraction by these prism rings is unavoidable. Some of the light that would reach a designated target area according to geometric optics will miss it due to diffraction. This diffraction loss may be of relevant magnitude for CPV applications. The results of published analytical calculations are evaluated, discussed, and compared to computer simulations and measurements.

  1. Seismic attenuation due to wave-induced flow

    SciTech Connect (OSTI)

    Pride, S.R.; Berryman, J.G.; Harris, J.M.

    2003-10-09

    Analytical expressions for three P-wave attenuation mechanisms in sedimentary rocks are given a unified theoretical framework. Two of the models concern wave-induced flow due to heterogeneity in the elastic moduli at mesoscopic scales (scales greater than grain sizes but smaller than wavelengths). In the first model, the heterogeneity is due to lithological variations (e.g., mixtures of sands and clays) with a single fluid saturating all the pores. In the second model, a single uniform lithology is saturated in mesoscopic ''patches'' by two immiscible fluids (e.g., air and water). In the third model, the heterogeneity is at ''microscopic'' grain scales (broken grain contacts and/or micro-cracks in the grains) and the associated fluid response corresponds to ''squirt flow''. The model of squirt flow derived here reduces to proper limits as any of the fluid bulk modulus, crack porosity, and/or frequency is reduced to zero. It is shown that squirt flow is incapable of explaining the measured level of loss (10{sup -2} < Q{sup -1} < 10{sup -1}) within the seismic band of frequencies (1 to 10{sup 4} Hz); however, either of the two mesoscopic scale models easily produce enough attenuation to explain the field data.

  2. Comments on Landau damping due to synchrotron frequency spread

    SciTech Connect (OSTI)

    Ng, K.Y.; /Fermilab

    2005-01-01

    An inductive/space-charge impedance shifts the synchrotron frequency downwards above/below transition, but it is often said that the coherent synchrotron frequency of the bunch is not shifted in the rigid-dipole mode. On the other hand, the incoherent synchrotron frequency due to the sinusoidal rf always spreads in the downward direction. This spread will therefore not be able to cover the coherent synchrotron frequency, implying that there will not be any Landau damping no matter how large the frequency spread is. By studying the dispersion relation, it is shown that the above argument is incorrect, and there will be Landau damping if there is sufficient frequency spread. The main reason is that the coherent frequency of the rigid-dipole mode will no longer remain unshifted in the presence of a synchrotron frequency spread.

  3. Detailed characteristics of intermittent current pulses due to positive corona

    SciTech Connect (OSTI)

    Liu, Yang Cui, Xiang; Lu, Tiebing; Wang, Zhenguo; Li, Xuebao; Xiang, Yu; Wang, Xiaobo

    2014-08-15

    In order to get detailed characteristics of intermittent current pulses due to positive corona such as the repetition rate of burst-pulse trains, the peak value ratio of the primary pulse to the secondary pulse, the number of pulses per burst, and the interval of the secondary pulses, a systematic study was carried out in a coaxial conductor-cylinder electrode system with the conductor electrode being set with a discharge point. Empirical formulae for the number of pulses per burst and the interval of the secondary pulses are first presented. A theoretical model based on the motion of the space-charge clouds is proposed. Analysis with the model gives explanations to the experimental results and reveals some new insights into the physical mechanism of positive intermittent corona.

  4. Excitation of flow instabilities due to nonlinear scale invariance

    SciTech Connect (OSTI)

    Prasad Datta, Dhurjati; Sen, Sudip

    2014-05-15

    A novel route to instabilities and turbulence in fluid and plasma flows is presented in kinetic Vlasov-Maxwell model. New kind of flow instabilities is shown to arise due to the availability of new kinetic energy sources which are absent in conventional treatments. The present approach is based on a scale invariant nonlinear analytic formalism developed to address irregular motions on a chaotic attractor or in turbulence in a more coherent manner. We have studied two specific applications of this turbulence generating mechanism. The warm plasma Langmuir wave dispersion relation is shown to become unstable in the presence of these multifractal measures. In the second application, these multifractal measures are shown to induce naturally non-Gaussian, i.e., a stretched, Gaussian distribution and anomalous transport for tracer particles from the turbulent advection-diffusion transport equation in a Vlasov plasma flow.

  5. Moisture Risk in Unvented Attics Due to Air Leakage Paths

    SciTech Connect (OSTI)

    Prahl, D.; Shaffer, M.

    2014-11-01

    IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Wärme und Feuchte instationär Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

  6. Moisture Risk in Unvented Attics Due to Air Leakage Paths

    SciTech Connect (OSTI)

    Prahl, D.; Shaffer, M.

    2014-11-01

    IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Warme und Feuchte instationar Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

  7. Crystallographic changes in lead zirconate titanate due to neutron irradiation

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

    Henriques, Alexandra; Graham, Joseph T.; Landsberger, Sheldon; Ihlefeld, Jon F.; Brennecka, Geoff L.; Brown, Donald W.; Forrester, Jennifer S.; Jones, Jacob L.

    2014-11-17

    Piezoelectric and ferroelectric materials are useful as the active element in non-destructive monitoring devices for high-radiation areas. Here, crystallographic structural refinement (i.e., the Rietveld method) is used to quantify the type and extent of structural changes in PbZr0.5Ti0.5O3 after exposure to a 1 MeV equivalent neutron fluence of 1.7 × 1015 neutrons/cm2. The results show a measurable decrease in the occupancy of Pb and O due to irradiation, with O vacancies in the tetragonal phase being created preferentially on one of the two O sites. The results demonstrate a method by which the effects of radiation on crystallographic structure maymore » be investigated.« less

  8. Crystallographic changes in lead zirconate titanate due to neutron irradiation

    SciTech Connect (OSTI)

    Henriques, Alexandra; Graham, Joseph T.; Landsberger, Sheldon; Ihlefeld, Jon F.; Brennecka, Geoff L.; Brown, Donald W.; Forrester, Jennifer S.; Jones, Jacob L.

    2014-11-15

    Piezoelectric and ferroelectric materials are useful as the active element in non-destructive monitoring devices for high-radiation areas. Here, crystallographic structural refinement (i.e., the Rietveld method) is used to quantify the type and extent of structural changes in PbZr{sub 0.5}Ti{sub 0.5}O{sub 3} after exposure to a 1 MeV equivalent neutron fluence of 1.7 × 10{sup 15} neutrons/cm{sup 2}. The results show a measurable decrease in the occupancy of Pb and O due to irradiation, with O vacancies in the tetragonal phase being created preferentially on one of the two O sites. The results demonstrate a method by which the effects of radiation on crystallographic structure may be investigated.

  9. Crystallographic changes in lead zirconate titanate due to neutron irradiation

    SciTech Connect (OSTI)

    Henriques, Alexandra; Graham, Joseph T.; Landsberger, Sheldon; Ihlefeld, Jon F.; Brennecka, Geoff L.; Brown, Donald W.; Forrester, Jennifer S.; Jones, Jacob L.

    2014-11-17

    Piezoelectric and ferroelectric materials are useful as the active element in non-destructive monitoring devices for high-radiation areas. Here, crystallographic structural refinement (i.e., the Rietveld method) is used to quantify the type and extent of structural changes in PbZr0.5Ti0.5O3 after exposure to a 1 MeV equivalent neutron fluence of 1.7 1015 neutrons/cm2. The results show a measurable decrease in the occupancy of Pb and O due to irradiation, with O vacancies in the tetragonal phase being created preferentially on one of the two O sites. The results demonstrate a method by which the effects of radiation on crystallographic structure may be investigated.

  10. Changes in Dimethyl Sulfide Oceanic Distribution due to Climate Change

    SciTech Connect (OSTI)

    Cameron-Smith, P; Elliott, S; Maltrud, M; Erickson, D; Wingenter, O

    2011-02-16

    Dimethyl sulfide (DMS) is one of the major precursors for aerosols and cloud condensation nuclei in the marine boundary layer over much of the remote ocean. Here they report on coupled climate simulations with a state-of-the-art global ocean biogeochemical model for DMS distribution and fluxes using present-day and future atmospheric CO{sub 2} concentrations. They find changes in zonal averaged DMS flux to the atmosphere of over 150% in the Southern Ocean. This is due to concurrent sea ice changes and ocean ecosystem composition shifts caused by changes in temperature, mixing, nutrient, and light regimes. The largest changes occur in a region already sensitive to climate change, so any resultant local CLAW/Gaia feedback of DMS on clouds, and thus radiative forcing, will be particularly important. A comparison of these results to prior studies shows that increasing model complexity is associted with reduced DMS emissions at the equator and increased emissions at high latitudes.

  11. Computer Simulation of Bubble Growth in Metals Due to He

    SciTech Connect (OSTI)

    FOILES, STEPHEN M.; HOYT, JEFFREY J.

    2001-03-01

    Atomistic simulations of the growth of helium bubbles in metals are performed. The metal is represented by embedded atom method potentials for palladium. The helium bubbles are treated via an expanding repulsive spherical potential within the metal lattice. The simulations predict bubble pressures that decrease monotonically with increasing helium to metal ratios. The swelling of the material associated with the bubble growth is also computed. It is found that the rate of swelling increases with increasing helium to metal ratio consistent with experimental observations on the swelling of metal tritides. Finally, the detailed defect structure due to the bubble growth was investigated. Dislocation networks are observed to form that connect the bubbles. Unlike early model assumptions, prismatic loops between the bubbles are not retained. These predictions are compared to available experimental evidence.

  12. Precursor detonation wave development in ANFO due to aluminum confinement

    SciTech Connect (OSTI)

    Jackson, Scott I; Klyanda, Charles B; Short, Mark

    2010-01-01

    Detonations in explosive mixtures of ammonium-nitrate-fuel-oil (ANFO) confined by aluminum allow for transport of detonation energy ahead of the detonation front due to the aluminum sound speed exceeding the detonation velocity. The net effect of this energy transport on the detonation is unclear. It could enhance the detonation by precompressing the explosive near the wall. Alternatively, it could decrease the explosive performance by crushing porosity required for initiation by shock compression or destroying confinement ahead of the detonation. At present, these phenomena are not well understood. But with slowly detonating, non-ideal high explosive (NIHE) systems becoming increasing prevalent, proper understanding and prediction of the performance of these metal-confined NIHE systems is desirable. Experiments are discussed that measured the effect of this ANFO detonation energy transported upstream of the front by a 76-mm-inner-diameter aluminum confining tube. Detonation velocity, detonation-front shape, and aluminum response are recorded as a function of confiner wall thickness and length. Detonation shape profiles display little curvature near the confining surface, which is attributed to energy transported upstream modifying the flow. Average detonation velocities were seen to increase with increasing confiner thickness, while wavefront curvature decreased due to the stiffer, subsonic confinement. Significant radial sidewall tube motion was observed immediately ahead of the detonation. Axial motion was also detected, which interfered with the front shape measurements in some cases. It was concluded that the confiner was able to transport energy ahead of the detonation and that this transport has a definite effect on the detonation by modifying its characteristic shape.

  13. Enhancement of Zirconolite Dissolution Due to Water Radiolysis

    SciTech Connect (OSTI)

    Tribet, Magaly; Moncoffre, Nathalie

    2007-07-01

    Zirconolite is a candidate host material for conditioning minor tri- and tetra-valent actinides arising from enhanced nuclear spent fuel reprocessing and partitioning, in the case of disposal of the nuclear waste. Its chemical durability has been studied here under charged particle-induced radiolysis (He{sup 2+} and proton external beams) to identify the possible effects of water radiolysis on the dissolution rates in pure water and to describe the alteration mechanisms. Two experimental geometries have been used in order to evaluate the influence of the following parameters: solid irradiation, water radiolysis. In the first geometry the beam gets through the sample before stopping at the surface/water interface. In the second one the beam stops before the surface/water interface. Results on the elemental releases due to the enhanced dissolution of the zirconolite surface during charged particle-induced irradiation of water are presented. Under radiolysis, an increase of one order of magnitude is observed in the Ti, Zr and Nd elemental releases. No difference in the total elemental releases can be noticed when the solid is also irradiated. (authors)

  14. Resource demand growth and sustainability due to increased world consumption

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

    Balatsky, Alexander V.; Balatsky, Galina I.; Borysov, Stanislav S.

    2015-03-20

    The paper aims at continuing the discussion on sustainability and attempts to forecast the impossibility of the expanding consumption worldwide due to the planet’s limited resources. As the population of China, India and other developing countries continue to increase, they would also require more natural and financial resources to sustain their growth. We coarsely estimate the volumes of these resources (energy, food, freshwater) and the gross domestic product (GDP) that would need to be achieved to bring the population of India and China to the current levels of consumption in the United States. We also provide estimations for potentially neededmore » immediate growth of the world resource consumption to meet this equality requirement. Given the tight historical correlation between GDP and energy consumption, the needed increase of GDP per capita in the developing world to the levels of the U.S. would deplete explored fossil fuel reserves in less than two decades. These estimates predict that the world economy would need to find a development model where growth would be achieved without heavy dependence on fossil fuels.« less

  15. Resource demand growth and sustainability due to increased world consumption

    SciTech Connect (OSTI)

    Balatsky, Alexander V.; Balatsky, Galina I.; Borysov, Stanislav S.

    2015-03-20

    The paper aims at continuing the discussion on sustainability and attempts to forecast the impossibility of the expanding consumption worldwide due to the planet’s limited resources. As the population of China, India and other developing countries continue to increase, they would also require more natural and financial resources to sustain their growth. We coarsely estimate the volumes of these resources (energy, food, freshwater) and the gross domestic product (GDP) that would need to be achieved to bring the population of India and China to the current levels of consumption in the United States. We also provide estimations for potentially needed immediate growth of the world resource consumption to meet this equality requirement. Given the tight historical correlation between GDP and energy consumption, the needed increase of GDP per capita in the developing world to the levels of the U.S. would deplete explored fossil fuel reserves in less than two decades. These estimates predict that the world economy would need to find a development model where growth would be achieved without heavy dependence on fossil fuels.

  16. Risk Due to Radiological Terror Attacks With Natural Radionuclides

    SciTech Connect (OSTI)

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva; Stan, Rydell

    2008-08-07

    The naturally occurring radionuclides radium (Ra-226) and polonium (Po-210) have the potential to be used for criminal acts. Analysis of international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (CSTO), operated at the University of Salzburg, shows that several acts of murder and terrorism with natural radionuclides have already been carried out in Europe and Russia. Five different modes of attack (T) are possible: (1) Covert irradiation of an individual in order to deliver a high individual dose; (2) Covert irradiation of a group of persons delivering a large collective dose; (3) Contamination of food or drink; (4) Generation of radioactive aerosols or solutions; (5) Combination of Ra-226 with conventional explosives (Dirty Bomb).This paper assesses the risk (R) of such criminal acts in terms of: (a) Probability of terrorist motivation deploying a certain attack mode T; (b) Probability of success by the terrorists for the selected attack mode T; (c) Primary damage consequence (C) to the attacked target (activity, dose); (d) Secondary damage consequence (C') to the attacked target (psychological and socio-economic effects); (e) Probability that the consequences (C, C') cannot be brought under control, resulting in a failure to manage successfully the emergency situation due to logistical and/or technical deficits in implementing adequate countermeasures. Extensive computer modelling is used to determine the potential impact of such a criminal attack on directly affected victims and on the environment.

  17. October 12

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

    Were down for a day recently due to a security problem and there was also a power outage at OSF. Upcoming downtimes: Nothing in October. New hardware: End of fiscal year orders are ...

  18. Solutal separation in a binary nanofluid due to thermodiffusion

    SciTech Connect (OSTI)

    Saghir, M.Z.; Yousefi, T.; Farahbakhsh, B.

    2015-03-10

    Transport phenomena in porous media have received considerable attention due to an increasing interest in geothermal processes, chemical catalytic reactors, waste storage (especially geological or ocean storage of carbon dioxide), etc. Among others, oil industry has shown an increasing interest in studying diffusion phenomenon. Nanofluid is a term used to describe the suspension of low concentration of metallic and non-metallic nanoparticles in a base fluid. The size of a nanoparticle ranges from 10 to 100nm, and the conventional fluids used are water, ethylene glycol (C{sub 2}H{sub 6}O{sub 2}) or engine oil. Various studies have proven that nanoparticles improve the heat transfer of a base fluid. However, using various nanofluids it has been shown that the results could vary depending on different initial concentrations. The main objective of this paper is to study the diffusion and the thermodiffusion effect in a nanofluid for different fluid/porous media configurations. In this configuration, a liquid layer surrounds a porous layer. The full Brinkman equation coupled with the heat and mass transfer equations have been solved numerically for the porous layer using the finite element technique. The full Navier stokes equation coupled with heat and mass transfer equations have been solved for the liquid layer using the finite element method. A constraint between the liquid and porous layer has been applied to ensure heat flow and mass transfer continuity is maintained. A square cavity filled with hydrocarbon nanofluid of a mixture of fullerene-toluene with varying concentration of fullerene has been subject to different heating conditions. The entire cavity has been considered to be fully wetted with nanofluid. Results have confirmed that in the presence of a nanofluid a heat transfer enhancement is present up to certain initial concentration of the fullerene. The heat convection coefficient has been found to be 16% higher when a nanofluid is used as the working

  19. Deactivation Mechanism of Cu/Zeolite SCR Catalyst Due to Reductive...

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

    Mechanism of CuZeolite SCR Catalyst Due to Reductive Hydrothermal Aging Deactivation Mechanism of CuZeolite SCR Catalyst Due to Reductive Hydrothermal Aging Better control for ...

  20. Plasmon losses due to electron-phonon scattering: The case of...

    Office of Scientific and Technical Information (OSTI)

    Plasmon losses due to electron-phonon scattering: The case of graphene encapsulated in hexagonal boron nitride Citation Details In-Document Search Title: Plasmon losses due to ...

  1. Delivery Due:

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

    ... consideration of overall customer satisfaction and conclusions of informed judgment. ... a rate of 35.00 per day for a compact car. If a rental rate higher than those identified ...

  2. Black Bear Prep plant replaces high-frequency screens with fine wire sieves

    SciTech Connect (OSTI)

    Barbee, C.J.; Nottingham, J.

    2007-12-15

    At the Black Bear prep plant (near Wharncliffe, WV, USA) the clean coal from the spirals traditionally reported to high-frequency screens, which removed high-ash clay fines. Screens have inherent inefficiencies that allow clean coal to report to the screen underflow. The goal of this project was to capture the maximum amount of spiral clean coal while still removing the high-ash clay material found in the spiral product. The reduction of the circulating load and plant downtime for unscheduled maintenance were projected as additional benefits. After the plant upgrade, the maintenance related to the high frequency screens was eliminated and an additional 2.27 tons per hour (tph) of fine coal was recovered, which resulted in a payback period of less than one year. The article was adapted from a paper presented at Coal Prep 2007 in April 2007, Lexington, KY, USA. 1 ref., 1 fig., 1 tab.

  3. 2014 PDSF User Meeting Minutes

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

    October 7 Attending Jeff, Mike, Zach, Jochen Outages Downtime 97 - 98 Eliza18 downtime 930 Science gateways downtime 105 Power spike caused PDSF network outage, many jobs ...

  4. Monte Carlo Implementation Of Up- Or Down-Scattering Due To Collisions...

    Office of Scientific and Technical Information (OSTI)

    Monte Carlo Implementation Of Up- Or Down-Scattering Due To Collisions With Material At Finite Temperature Citation Details In-Document Search Title: Monte Carlo Implementation Of ...

  5. Wind turbine reliability : understanding and minimizing wind turbine operation and maintenance costs.

    SciTech Connect (OSTI)

    Not Available

    2004-11-01

    Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. Cost of energy (COE) is a key project evaluation metric, both in commercial applications and in the U.S. federal wind energy program. To reflect this commercial reality, the wind energy research community has adopted COE as a decision-making and technology evaluation metric. The COE metric accounts for the effects of reliability through levelized replacement cost and unscheduled maintenance cost parameters. However, unlike the other cost contributors, such as initial capital investment and scheduled maintenance and operating expenses, costs associated with component failures are necessarily speculative. They are based on assumptions about the reliability of components that in many cases have not been operated for a complete life cycle. Due to the logistical and practical difficulty of replacing major components in a wind turbine, unanticipated failures (especially serial failures) can have a large impact on the economics of a project. The uncertainty associated with long-term component reliability has direct bearing on the confidence level associated with COE projections. In addition, wind turbine technology is evolving. New materials and designs are being incorporated in contemporary wind turbines with the ultimate goal of reducing weight, controlling loads, and improving energy capture. While the goal of these innovations is reduction in the COE, there is a

  6. Anomalies in the theory of viscous energy losses due to shear...

    Office of Scientific and Technical Information (OSTI)

    Anomalies in the theory of viscous energy losses due to shear in rotational MEMS resonators. Citation Details In-Document Search Title: Anomalies in the theory of viscous energy ...

  7. Directives Due for Review Before 9-30-2016 - DOE Directives, Delegations,

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

    and Requirements Due for Review Before 9-30-2016 by Diane Johnson PDF document icon DirectivesUpForReview-EOFY2016.pdf - PDF document, 245 KB (251440 bytes)

  8. MODELING OF LONG-TERM FATE OF MOBILIZED FINES DUE TO DAM-EMBANKMENT...

    Office of Scientific and Technical Information (OSTI)

    MODELING OF LONG-TERM FATE OF MOBILIZED FINES DUE TO DAM-EMBANKMENT INTERFACIAL DISLOCATIONS Citation Details In-Document Search Title: MODELING OF LONG-TERM FATE OF MOBILIZED ...

  9. Vortex motion of dust particles due to non-conservative ion drag...

    Office of Scientific and Technical Information (OSTI)

    in a plasma This content will become publicly available on February 12, 2017 Title: Vortex motion of dust particles due to non-conservative ion drag force in a plasma Authors: ...

  10. MODELING OF LONG-TERM FATE OF MOBILIZED FINES DUE TO DAM-EMBANKMENT...

    Office of Scientific and Technical Information (OSTI)

    Conference: MODELING OF LONG-TERM FATE OF MOBILIZED FINES DUE TO DAM-EMBANKMENT INTERFACIAL DISLOCATIONS Citation Details In-Document Search Title: MODELING OF LONG-TERM FATE OF ...

  11. Enforcement Policy Statement: Treatment of Late-Arriving Goods Due to West

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

    Treatment of Late-Arriving Goods Due to West Coast Port Closure February 27, 2015 Closures at 29 West Coast marine ports in February 2015 due to a labor dispute have resulted in significant delays for certain goods entering the United States through those ports, including covered products and equipment subject to DOE energy or water conservation standards. Covered products and equipment subject to energy or water conservation standards must meet the standard(s) that are effective on the date

  12. Fact #668: March 28, 2011 Time Wasted Due to Traffic Congestion |

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

    Department of Energy 8: March 28, 2011 Time Wasted Due to Traffic Congestion Fact #668: March 28, 2011 Time Wasted Due to Traffic Congestion According to the Texas Transportation Institute's latest study on traffic congestion, all urban areas have experienced increased congestion in the seventeen-year period from 1982 to 2009, but congestion has changed little from 1999 to 2009. As expected, traffic congestion is worse in very large urban areas, but congestion has grown in small areas, too.

  13. Enhanced spin Seebeck effect signal due to spin-momentum locked topological

    Office of Scientific and Technical Information (OSTI)

    surface states (Journal Article) | SciTech Connect Journal Article: Enhanced spin Seebeck effect signal due to spin-momentum locked topological surface states Citation Details In-Document Search Title: Enhanced spin Seebeck effect signal due to spin-momentum locked topological surface states Spin-momentum locking in protected surface states enables efficient electrical detection of magnon decay at a magnetic-insulator/topological-insulator heterojunction. Here we demonstrate this property

  14. Study finds radioactivity around Los Alamos largely due to natural sources

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

    Radioactivity largely due to natural sources Study finds radioactivity around Los Alamos largely due to natural sources The study was subsequently peer reviewed externally by scientists at Colorado State University and internally within the Lab. December 10, 2008 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma

  15. Program for Numerical Simulation of Beam Losses due to Interaction with Residual Gas

    SciTech Connect (OSTI)

    Karamysheva, G.; Skripka, G.

    2010-01-05

    Program for estimation of the beam losses of light ions due to interaction with the residual gas has been written. The loss of beam intensity is determined by the cross sections for loss processes respecting different ion energies and depends on the pressure of the residual gas. The beam losses due to interaction with the residual gas by the example of C400 cyclotron (IBA, Belgium) were done.

  16. High redshift signatures in the 21 cm forest due to cosmic string wakes

    SciTech Connect (OSTI)

    Tashiro, Hiroyuki; Sekiguchi, Toyokazu; Silk, Joseph E-mail: toyokazu.sekiguchi@nagoya-u.jp

    2014-01-01

    Cosmic strings induce minihalo formation in the early universe. The resultant minihalos cluster in string wakes and create a ''21 cm forest'' against the cosmic microwave background (CMB) spectrum. Such a 21 cm forest can contribute to angular fluctuations of redshifted 21 cm signals integrated along the line of sight. We calculate the root-mean-square amplitude of the 21 cm fluctuations due to strings and show that these fluctuations can dominate signals from minihalos due to primordial density fluctuations at high redshift (z?>10), even if the string tension is below the current upper bound, G? < 1.5 10{sup ?7}. Our results also predict that the Square Kilometre Array (SKA) can potentially detect the 21 cm fluctuations due to strings with G? ? 7.5 10{sup ?8} for the single frequency band case and 4.0 10{sup ?8} for the multi-frequency band case.

  17. Residual stress relief due to fatigue in tetragonal lead zirconate titanate ceramics

    SciTech Connect (OSTI)

    Hall, D. A.; Mori, T. [School of Materials, University of Manchester, Grosvenor St., Manchester M1 7HS (United Kingdom); Comyn, T. P. [Institute for Materials Research, Woodhouse Lane, University of Leeds, LS2 9JT (United Kingdom); Ringgaard, E. [Meggitt Sensing Systems, Hejreskovvej 18A, 3490 Kvistgaard (Denmark); Wright, J. P. [ESRF, 6 Rue Jules Horowitz, BP-220, 38043 Grenoble Cedex (France)

    2013-07-14

    High energy synchrotron XRD was employed to determine the lattice strain {epsilon}{l_brace}111{r_brace}and diffraction peak intensity ratio R{l_brace}200{r_brace}in tetragonal PZT ceramics, both in the virgin poled state and after a bipolar fatigue experiment. It was shown that the occurrence of microstructural damage during fatigue was accompanied by a reduction in the gradient of the {epsilon}{l_brace}111{r_brace}-cos{sup 2} {psi} plot, indicating a reduction in the level of residual stress due to poling. In contrast, the fraction of oriented 90 Degree-Sign ferroelectric domains, quantified in terms of R{l_brace}200{r_brace}, was not affected significantly by fatigue. The change in residual stress due to fatigue is interpreted in terms of a change in the average elastic stiffness of the polycrystalline matrix due to the presence of inter-granular microcracks.

  18. Frequency Shift of the Cesium Clock Transition due to Blackbody Radiation

    SciTech Connect (OSTI)

    Angstmann, E. J.; Dzuba, V. A.; Flambaum, V. V.

    2006-07-28

    We perform ab initio calculations of the frequency shift induced by a static electric field on the cesium clock hyperfine transition. The calculations are used to find the frequency shifts due to blackbody radiation. Our result [{delta}{nu}/E{sup 2}=-2.26(2)x10{sup -10} Hz/(V/m){sup 2}] is in good agreement with early measurements and ab initio calculations performed in other groups. We present arguments against recent claims that the actual value of the effect might be smaller. The difference ({approx}10%) between ab initio and semiempirical calculations is due to the contribution of the continuum spectrum in the sum over intermediate states.

  19. Radar transponder operation with compensation for distortion due to amplitude modulation

    DOE Patents [OSTI]

    Ormesher, Richard C.; Tise, Bertice L.; Axline, Jr., Robert M.

    2011-01-04

    In radar transponder operation, a variably delayed gating signal is used to gate a received radar pulse and thereby produce a corresponding gated radar pulse for transmission back to the source of the received radar pulse. This compensates for signal distortion due to amplitude modulation on the retransmitted pulse.

  20. Influence of pitch, twist, and taper on a blade`s performance loss due to roughness

    SciTech Connect (OSTI)

    Tangler, J.L.

    1996-12-31

    The purpose of this study was to determine the influence of blade geometric parameters such as pitch, twist, and taper on a blade`s sensitivity to leading edge roughness. The approach began with an evaluation of available test data of performance degradation due to roughness effects for several rotors. In addition to airfoil geometry, this evaluation suggested that a rotor`s sensitivity to roughness was also influenced by the blade geometric parameters. Parametric studies were conducted using the PROP computer code with wind-tunnel airfoil characteristics for smooth and rough surface conditions to quantify the performance loss due to roughness for tapered and twisted blades relative to a constant-chord, non-twisted blade at several blade pitch angles. The results indicate that a constant-chord, non-twisted blade pitched toward stall will have the greatest losses due to roughness. The use of twist, taper, and positive blade pitch angles all help reduce the angle-of-attack distribution along the blade for a given wind speed and the associated performance degradation due to roughness. 8 refs., 6 figs.

  1. Critical-Current Reduction in Thin Superconducting Wires Due to Current Crowding

    SciTech Connect (OSTI)

    Hortensius, H.L.; Driessen, E.F.C.; Klapwijk, T.M.; Berggren, K.K.; Clem, John

    2012-05-03

    We demonstrate experimentally that the critical current in superconducting NbTiN wires is dependent on their geometrical shape, due to current-crowding effects. Geometric patterns such as 90{degrees} corners and sudden expansions of wire width are shown to result in the reduction of critical currents. The results are relevant for single-photon detectors as well as parametric amplifiers.

  2. Universality of the acceleration due to gravity on the surface of a rapidly rotating neutron star

    SciTech Connect (OSTI)

    AlGendy, Mohammad; Morsink, Sharon M.

    2014-08-20

    On the surface of a rapidly rotating neutron star, the effective centrifugal force decreases the effective acceleration due to gravity (as measured in the rotating frame) at the equator while increasing the acceleration at the poles due to the centrifugal flattening of the star into an oblate spheroid. We compute the effective gravitational acceleration for relativistic rapidly rotating neutron stars and show that for a star with mass M, equatorial radius R{sub e} , and angular velocity ?, the deviations of the effective acceleration due to gravity from the nonrotating case take on a universal form that depends only on the compactness ratio M/R{sub e} , the dimensionless square of the angular velocity ?{sup 2}R{sub e}{sup 3}/GM, and the latitude on the star's surface. This dependence is universal, in that it has very little dependence on the neutron star's equation of state. The effective gravity is expanded in the slow-rotation limit to show the dependence on the effective centrifugal force, oblate shape of the star, and the quadrupole moment of the gravitational field. In addition, an empirical fit and simple formula for the effective gravity is found. We find that the increase in the acceleration due to gravity at the poles is of the same order of magnitude as the decrease in the effective acceleration due to gravity at the equator for all realistic value of mass, radius, and spin. For neutron stars that spin with frequencies near 600 Hz, the difference between the effective gravity at the poles and the equator is about 20%.

  3. Wireless Sensor Network for Advanced Energy Management Solutions

    SciTech Connect (OSTI)

    Peter J. Theisen; Bin Lu, Charles J. Luebke

    2009-09-23

    Eaton has developed an advanced energy management solution that has been deployed to several Industries of the Future (IoF) sites. This demonstrated energy savings and reduced unscheduled downtime through an improved means for performing predictive diagnostics and energy efficiency estimation. Eaton has developed a suite of online, continuous, and inferential algorithms that utilize motor current signature analysis (MCSA) and motor power signature analysis (MPSA) techniques to detect and predict the health condition and energy usage condition of motors and their connect loads. Eaton has also developed a hardware and software platform that provided a means to develop and test these advanced algorithms in the field. Results from lab validation and field trials have demonstrated that the developed advanced algorithms are able to detect motor and load inefficiency and performance degradation. Eaton investigated the performance of Wireless Sensor Networks (WSN) within various industrial facilities to understand concerns about topology and environmental conditions that have precluded broad adoption by the industry to date. A Wireless Link Assessment System (WLAS), was used to validate wireless performance under a variety of conditions. Results demonstrated that wireless networks can provide adequate performance in most facilities when properly specified and deployed. Customers from various IoF expressed interest in applying wireless more broadly for selected applications, but continue to prefer utilizing existing, wired field bus networks for most sensor based applications that will tie into their existing Computerized Motor Maintenance Systems (CMMS). As a result, wireless technology was de-emphasized within the project, and a greater focus placed on energy efficiency/predictive diagnostics. Commercially available wireless networks were only utilized in field test sites to facilitate collection of motor wellness information, and no wireless sensor network products were

  4. Analyzing health risks due to trace substance emissions from utility fossil-fired plants. Final report

    SciTech Connect (OSTI)

    1997-12-01

    EPRI has undertaken a number of project addressing a range of issues on the potential health effects due to long-term inhalation exposure to trace substances emitted from utility stacks. This report describes particular studies conducted to assess the health risks due to emissions from groups of power plants operated by individual utility companies. Researchers conducted specialized risk assessments for each of the power plants involved by incorporating utility-specific data into a modeling framework developed as part of EPRI`s Comprehensive Risk Evaluation (CORE) project to tailor the analysis for the individual utility. The results indicated the value of using more up-to-date, precise data in conducting risk assessments, rather than default assumptions. The report also describes CRAFT, the Comprehensive Risk Assessment Framework for Toxics software package, developed to perform these utility-wide air toxics risk assessments.

  5. Study on structural damage of ships due to collision and grounding

    SciTech Connect (OSTI)

    Kuroiwa, T.; Nakamura, T.; Kawamoto, Y.; Kondo, M.; Kusuba, S.

    1994-12-31

    In this paper, structural failure of tankers due to collisions and groundings is studied. To investigate failure mechanism and energy absorption capacity of ship structures. Experiments and numerical simulations are carried out. In the numerical simulations, failure of fillet welds and rupture of plates are taken into account. To investigate structural integrity of Mid-Deck Tanker, which was newly developed to reduce accidental oil outflow, numerical simulations of grounding of the tanker are performed.

  6. Process for the measurement of performance loss due to series resistance in

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

    photovoltaic devices under field conditions - Energy Innovation Portal Find More Like This Return to Search Process for the measurement of performance loss due to series resistance in photovoltaic devices under field conditions National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary An unexpected increase in the series resistance in a photovoltaic module can be a serious problem; not only does the increased resistance reduce current flow - and

  7. Lowe's "Toolbox for Education" grant applications due by October 12

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

    Lowe's "Toolbox for Education" Grant Applications Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Lowe's "Toolbox for Education" grant applications due by October 12 Five million dollars is available for the 2012-13 school year. September 1, 2012 dummy image Read our archives Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email Over the

  8. Reduction in performance due to recirculation in mechanical-draft cooling towers

    SciTech Connect (OSTI)

    Kroger, D.G. )

    1989-01-01

    The influence of recirculating warm plume air on the performance of mechanical-draft cooling towers is investigated analytically, numerically and experimentally. It is shown that the amount of recirculation that occurs is a function of the flow and the thermal and geometric characteristics of the tower. The presence of a wind wall tends to reduce the mount of recirculation. An equation is presented with which the performance effectiveness due to recirculation can be evaluated approximately for a mechanical-draft cooling tower.

  9. 2014 call for NERSC's Data Intensive Computing Pilot Program Due December

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

    10 NERSC's Data Intensive Computing Pilot Program 2014 call for NERSC's Data Intensive Computing Pilot Program Due December 10 November 18, 2013 by Francesca Verdier NERSC's Data Intensive Computing Pilot Program is now open for its second round of allocations to projects in data intensive science. This pilot aims to support and enable scientists to tackle their most demanding data intensive challenges. Selected projects will be piloting new methods and technologies targeting data

  10. Subsidence due to fluid withdrawal: a survey of analytical capabilities. [1225 citations

    SciTech Connect (OSTI)

    Engi, D.

    1985-08-01

    An extensive review of the literature was conducted in the area of land subsidence due to the withdrawal of fluids. A method of categorizing the citations was developed to facilitate identification of references relating to specific fields of interest. A brief review of the materials represented by the bibliography indicates the state-of-the-art within this area. The bibliography (containing 1225 citations) is presented in its categorized form. 5 figs., 3 tabs.

  11. Call for nominations for NERSC HPC Achievement Awards Due December 16

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

    nominations for NERSC HPC Achievement Awards Call for nominations for NERSC HPC Achievement Awards Due December 16 November 18, 2013 by Francesca Verdier Nominations are open for the 2014 NERSC Award for Innovative Use of High Performance Computing and the 2014 NERSC Award for High Impact Scientific Achievement. NERSC Principal Investigators, Project Managers, PI Proxies, and DOE Program Managers may nominate any NERSC user or collaboration. The deadline for nominations is Mon. Dec. 16, 2013.

  12. High energy emission from galaxy clusters and particle acceleration due to MHD turbulence

    SciTech Connect (OSTI)

    Brunetti, G.; Cassano, R.; Blasi, P.; Gabici, S.

    2009-04-08

    In the next years the FERMI gamma ray telescope and the Cherenkov telescopes will put very stringent constraints to models of gamma ray emission from galaxy clusters providing crucial information on relativistic particles in the inter-galactic-medium.We derive the broad band non-thermal spectrum of galaxy clusters in the context of general calculations in which relativistic particles (protons and secondary electrons due to proton-proton collisions) interact with MHD turbulence generated in the cluster volume during cluster mergers, and discuss the importance of future gamma ray observations.

  13. Nonlinear dissipation of circularly polarized Alfven waves due to the beam-induced obliquely propagating waves

    SciTech Connect (OSTI)

    Nariyuki, Y.; Hada, T.; Tsubouchi, K.

    2012-08-15

    In the present study, the dissipation processes of circularly polarized Alfven waves in solar wind plasmas including beam components are numerically discussed by using a 2-D hybrid simulation code. Numerical results suggest that the parent Alfven waves are rapidly dissipated due to the presence of the beam-induced obliquely propagating waves, such as kinetic Alfven waves. The nonlinear wave-wave coupling is directly evaluated by using the induction equation for the parent wave. It is also observed both in the 1-D and 2-D simulations that the presence of large amplitude Alfven waves strongly suppresses the beam instabilities.

  14. Influence of architectural screens on rooftop concentrations due to effluent from short stacks

    SciTech Connect (OSTI)

    Petersen, R.L.; Carter, J.J.; Ratcliff, M.A.

    1999-07-01

    This paper describes the wind tunnel study conducted on behalf of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) to evaluate and quantify the effect of architectural screens on rooftop concentration levels due to effluent from short stacks. An equivalent stack height (ESH) concept is introduced, which is used to develop a stack height reduction (SHR) factor that may be used in conjunction with existing stack design procedures found in the 1997 ASHRAE Handbook--Fundamentals to account for the presence of architectural screens.

  15. Methodology to predict the number of forced outages due to creep failure

    SciTech Connect (OSTI)

    Palermo, J.V. Jr.

    1996-12-31

    All alloy metals at a temperature above 950 degrees Fahrenheit experience creep damage. Creep failures in boiler tubes usually begin after 25 to 40 years of operation. Since creep damage is irreversible, the only remedy is to replace the tube sections. By predicting the number of failures per year, the utility can make the best economic decision concerning tube replacement. This paper describes a methodology to calculate the number of forced outages per yea due to creep failures. This methodology is particularly useful to utilities that have boilers that have at least 25 years of operation.

  16. Diamond formation due to a pH drop during fluid–rock interactions

    SciTech Connect (OSTI)

    Sverjensky, Dimitri A.; Huang, Fang

    2015-11-03

    Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly with eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.

  17. Diamond formation due to a pH drop during fluid–rock interactions

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

    Sverjensky, Dimitri A.; Huang, Fang

    2015-11-03

    Diamond formation has typically been attributed to redox reactions during precipitation from fluids or magmas. Either the oxidation of methane or the reduction of carbon dioxide has been suggested, based on simplistic models of deep fluids consisting of mixtures of dissolved neutral gas molecules without consideration of aqueous ions. The role of pH changes associated with water–silicate rock interactions during diamond formation is unknown. Here we show that diamonds could form due to a drop in pH during water–rock interactions. We use a recent theoretical model of deep fluids that includes ions, to show that fluid can react irreversibly withmore » eclogite at 900 °C and 5.0 GPa, generating diamond and secondary minerals due to a decrease in pH at almost constant oxygen fugacity. Overall, our results constitute a new quantitative theory of diamond formation as a consequence of the reaction of deep fluids with the rock types that they encounter during migration. Diamond can form in the deep Earth during water–rock interactions without changes in oxidation state.« less

  18. Assessment of damage to the desert surfaces of Kuwait due to the Gulf War

    SciTech Connect (OSTI)

    El-Baz, F. . Center for Remote Sensing); Al-Ajmi, D. . Environmental and Earth Sciences Div.)

    1993-01-01

    This is a preliminary report on a joint research project by Boston University and the Kuwait Institute for Scientific Research that commenced in April 1992. The project aim is to establish the extent and nature of environmental damage to the desert surface and coastal zone of Kuwait due to the Gulf War and its aftermath. Change detection image enhancement techniques were employed to enhance environmental change by comparison of Landsat Thematic Mapper images obtained before the wars and after the cessation of the oil and well fires. Higher resolution SPOT images were also utilized to evaluate the nature of the environmental damage to specific areas. The most prominent changes were due to: (1) the deposition of oil and course-grained soot on the desert surface as a result of oil rain'' from the plume that emanated from the oil well fires; (2) the formation of hundreds of oil lakes, from oil seepage at the damaged oil well heads; (3) the mobilization of sand and dust and (4) the pollution of segments of the coastal zone by the deposition of oil from several oil spills. Interpretation of satellite image data are checked in the field to confirm the observations, and to assess the nature of the damage. Final results will be utilized in establishing the needs for remedial action to counteract the harmful effects of the various types of damage to the environment of Kuwait.

  19. Optical losses of solar mirrors due to atmospheric contamination at Liberal, Kansas and Oologah, Oklahoma

    SciTech Connect (OSTI)

    Dake, L.S.; Lind, M.A.

    1981-09-01

    An assessment is presented of the effect of outdoor exposure on mirrors located at two sites selected for potential solar cogeneration/repowering facilities: Liberal, Kansas and Oologah, Oklahoma. Mirror coupons were placed on tracking heliostat simulators located in the proposed heliostat fields and were removed periodically. The spectral hemispherical and diffuse reflectances of these coupons were measured. Representative samples were analyzed for the chemical composition of the dust particulates using SEM/EDX. Other samples were washed with a high pressure spray and recharacterized to determine the effects of the residual dust. Average specular reflectance losses over the entire test period (up to 504 days) were 6 to 12%, with a range of 1 to 30%. Specular reflectance losses varied widely from day to day depending on local weather conditions. The losses due to scattering were 2 to 5 times greater than the losses due to absorptance. The average degradation rate over the first thirty days was an order of magnitude larger than the average degradation rate over the entire sampling period. Specular reflectance loss rates averaged 0.5% per day and greater between periods of natural cleaning. The chemical composition of the dust on the mirrors was characteristic of the indigenous soil, with some samples also showing the presence of sulfur and chlorine, possibly from cooling tower drift.

  20. Field collapse due to band-tail charge in amorphous silicon solar cells

    SciTech Connect (OSTI)

    Wang, Qi; Crandall, R.S.; Schiff, E.A.

    1996-05-01

    It is common for the fill factor to decrease with increasing illumination intensity in hydrogenated amorphous silicon solar cells. This is especially critical for thicker solar cells, because the decrease is more severe than in thinner cells. Usually, the fill factor under uniformly absorbed red light changes much more than under strongly absorbed blue light. The cause of this is usually assumed to arise from space charge trapped in deep defect states. The authors model this behavior of solar cells using the Analysis of Microelectronic and Photonic Structures (AMPS) simulation program. The simulation shows that the decrease in fill factor is caused by photogenerated space charge trapped in the band-tail states rather than in defects. This charge screens the applied field, reducing the internal field. Owing to its lower drift mobility, the space charge due to holes exceeds that due to electrons and is the main cause of the field screening. The space charge in midgap states is small compared with that in the tails and can be ignored under normal solar-cell operating conditions. Experimentally, the authors measured the photocapacitance as a means to probe the collapsed field. They also explored the light intensity dependence of photocapacitance and explain the decrease of FF with the increasing light intensity.

  1. Time delay and magnification centroid due to gravitational lensing by black holes and naked singularities

    SciTech Connect (OSTI)

    Virbhadra, K. S.; Keeton, C. R.

    2008-06-15

    We model the massive dark object at the center of the Galaxy as a Schwarzschild black hole as well as Janis-Newman-Winicour naked singularities, characterized by the mass and scalar charge parameters, and study gravitational lensing (particularly time delay, magnification centroid, and total magnification) by them. We find that the lensing features are qualitatively similar (though quantitatively different) for Schwarzschild black holes, weakly naked, and marginally strongly naked singularities. However, the lensing characteristics of strongly naked singularities are qualitatively very different from those due to Schwarzschild black holes. The images produced by Schwarzschild black hole lenses and weakly naked and marginally strongly naked singularity lenses always have positive time delays. On the other hand, strongly naked singularity lenses can give rise to images with positive, zero, or negative time delays. In particular, for a large angular source position the direct image (the outermost image on the same side as the source) due to strongly naked singularity lensing always has a negative time delay. We also found that the scalar field decreases the time delay and increases the total magnification of images; this result could have important implications for cosmology. As the Janis-Newman-Winicour metric also describes the exterior gravitational field of a scalar star, naked singularities as well as scalar star lenses, if these exist in nature, will serve as more efficient cosmic telescopes than regular gravitational lenses.

  2. Wakefield and RF Kicks Due to Coupler Asymmetry in TESLA-Type Accelerating Cavities

    SciTech Connect (OSTI)

    Bane, K.L.F.; Adolphsen, C.; Li, Z.; Dohlus, M.; Zagorodnov, I.; Gonin, I.; Lunin, A.; Solyak, N.; Yakovlev, V.; Gjonaj, E.; Weiland, T.; /Darmstadt, Tech. Hochsch.

    2008-07-07

    In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, due to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius 39 mm. Note that the couplers reach closer to the axis than the irises, down to a distance of 30 mm.

  3. Ion emittance growth due to focusing modulation from slipping electron bunch

    SciTech Connect (OSTI)

    Wang, G.

    2015-02-17

    Low energy RHIC operation has to be operated at an energy ranging from γ = 4.1 to γ = 10. The energy variation causes the change of revolution frequency. While the rf system for the circulating ion will operate at an exact harmonic of the revolution frequency (h=60 for 4.5 MHz rf and h=360 for 28 MHz rf.), the superconducting rf system for the cooling electron beam does not have a frequency tuning range that is wide enough to cover the required changes of revolution frequency. As a result, electron bunches will sit at different locations along the ion bunch from turn to turn, i.e. the slipping of the electron bunch with respect to the circulating ion bunch. At cooling section, ions see a coherent focusing force due to the electrons’ space charge, which differs from turn to turn due to the slipping. We will try to estimate how this irregular focusing affects the transverse emittance of the ion bunch.

  4. Continuum-kinetic-microscopic model of lung clearance due to core-annular fluid entrainment

    SciTech Connect (OSTI)

    Mitran, Sorin

    2013-07-01

    The human lung is protected against aspirated infectious and toxic agents by a thin liquid layer lining the interior of the airways. This airway surface liquid is a bilayer composed of a viscoelastic mucus layer supported by a fluid film known as the periciliary liquid. The viscoelastic behavior of the mucus layer is principally due to long-chain polymers known as mucins. The airway surface liquid is cleared from the lung by ciliary transport, surface tension gradients, and airflow shear forces. This work presents a multiscale model of the effect of airflow shear forces, as exerted by tidal breathing and cough, upon clearance. The composition of the mucus layer is complex and variable in time. To avoid the restrictions imposed by adopting a viscoelastic flow model of limited validity, a multiscale computational model is introduced in which the continuum-level properties of the airway surface liquid are determined by microscopic simulation of long-chain polymers. A bridge between microscopic and continuum levels is constructed through a kinetic-level probability density function describing polymer chain configurations. The overall multiscale framework is especially suited to biological problems due to the flexibility afforded in specifying microscopic constituents, and examining the effects of various constituents upon overall mucus transport at the continuum scale.

  5. CALCULATING ENERGY STORAGE DUE TO TOPOLOGICAL CHANGES IN EMERGING ACTIVE REGION NOAA AR 11112

    SciTech Connect (OSTI)

    Tarr, Lucas; Longcope, Dana

    2012-04-10

    The minimum current corona model provides a way to estimate stored coronal energy using the number of field lines connecting regions of positive and negative photospheric flux. This information is quantified by the net flux connecting pairs of opposing regions in a connectivity matrix. Changes in the coronal magnetic field, due to processes such as magnetic reconnection, manifest themselves as changes in the connectivity matrix. However, the connectivity matrix will also change when flux sources emerge or submerge through the photosphere, as often happens in active regions. We have developed an algorithm to estimate the changes in flux due to emergence and submergence of magnetic flux sources. These estimated changes must be accounted for in order to quantify storage and release of magnetic energy in the corona. To perform this calculation over extended periods of time, we must additionally have a consistently labeled connectivity matrix over the entire observational time span. We have therefore developed an automated tracking algorithm to generate a consistent connectivity matrix as the photospheric source regions evolve over time. We have applied this method to NOAA Active Region 11112, which underwent a GOES M2.9 class flare around 19:00 on 2010 October 16th, and calculated a lower bound on the free magnetic energy buildup of {approx}8.25 Multiplication-Sign 10{sup 30} erg over 3 days.

  6. Potential increases in natural radon emissions due to heating of the Yucca Mountain rock mass

    SciTech Connect (OSTI)

    Pescatore, C.; Sullivan, T.M.

    1992-02-01

    Heating of the rock mass by the spent fuel in the proposed repository at Yucca Mountain will cause extra amounts of natural radon to diffuse into the fracture system and to migrate faster to the accessible environment. Indeed, free-convection currents due to heating will act to shorten the radon travel times and will cause larger releases than would be possible under undistributed conditions. To estimate the amount of additional radon released due to heating of the Yucca Mountain rock mass, we obtain an expression for the release enhancement factor, E. This factor is defined as the ratio between the total flux of radon at the surface of the mountain before and after closure of the repository assuming the only cause of disturbance to be the heating of the rock mass. With appropriate approximations and using a heat load representative of that expected at Yucca Mountain, the present calculations indicate that the average enhancement factor over the first 10,000 years will be 4.5 as a minimum. These calculations are based on the assumption that barometric pumping does not significantly influence radon release. The latter assumption will need to be substantiated.

  7. Enhanced Ge/Si(001) island areal density and self-organization due to P predeposition

    SciTech Connect (OSTI)

    Cho, B.; Bareno, J.; Petrov, I.; Greene, J. E.

    2011-05-01

    The predeposition of P, with coverages {theta}{sub P} ranging from 0 to 1 ML, on Si(001) significantly increases both the areal density and spatial self-organization of Ge islands grown by gas-source molecular beam epitaxy from hydride precursors. The Ge island density {rho}{sub Ge} initially increases with {theta}{sub P}, reaching a maximum of 1.4 x 10{sup 10} cm{sup -2} at {theta}{sub P} = 0.7 ML, a factor of four times higher than on bare Si(001) under the same deposition conditions, before decreasing at higher P coverages. The increase in {rho}{sub Ge}({theta}{sub P}) is due to a corresponding decrease in Ge adatom mean free paths resulting from passivation of surface dangling bonds by adsorbed pentavalent P atoms which, in addition, leads to surface roughening and, therefore, higher Ge coverages at constant Ge{sub 2}H{sub 6} dose. As {theta}{sub P} (and hence, {rho}{sub Ge}) increases, so does the degree of Ge island ordering along <100> directions due to the anisotropic strain field surrounding individual islands. Similar results are obtained for Ge island growth on P-doped Si(001) layers where strong P surface segregation provides partial monolayer coverage prior to Ge deposition.

  8. Transient Eddy Current Response Due to a Subsurface Crack in a Conductive Plate

    SciTech Connect (OSTI)

    Fangwei Fu

    2006-08-09

    Eddy current nondestructive evaluation (NDE) is usually carried out by exciting a time harmonic field using an inductive probe. However, a viable alternative is to use transient eddy current NDE in which a current pulse in a driver coil produces a transient .eld in a conductor that decays at a rate dependent on the conductivity and the permeability of the material and the coil configuration. By using transient eddy current, it is possible to estimate the properties of the conductive medium and to locate and size potential .aws from the measured probe response. The fundamental study described in this dissertation seeks to establish a theoretical understanding of the transient eddy current NDE. Compared with the Fourier transform method, the derived analytical formulations are more convenient when the transient eddy current response within a narrow time range is evaluated. The theoretical analysis provides a valuable tool to study the effect of layer thickness, location of defect, crack opening as well as the optimization of probe design. Analytical expressions have been developed to evaluate the transient response due to eddy currents in a conductive plate based on two asymptotic series. One series converges rapidly for a short time regime and the other for a long time regime and both of them agree with the results calculated by fast Fourier transform over all the times considered. The idea of asymptotic expansion is further applied to determine the induced electromotive force (EMF) in a pick-up coil due to eddy currents in a cylindrical rod. Starting from frequency domain representation, a quasi-static time domain dyadic Green's function for an electric source in a conductive plate has been derived. The resulting expression has three parts; a free space term, multiple image terms and partial reflection terms. The dyadic Green's function serves as the kernel of an electric field integral equation which defines the interaction of an ideal crack with the transient

  9. Catalyst deactivation due to deposition of reaction products in macropores during hydroprocessing of petroleum residuals

    SciTech Connect (OSTI)

    Khang, S.J.; Mosby, J.F.

    1986-04-01

    A pore-filling model is proposed to describe deactivation of hydroprocessing catalysts of a wide-pore structure in well-mixed and plug-flow reactors where the catalyst pellets are deactivated due to slow and uniform deposition of reaction products (mostly metal compounds) in their macropores. The model based on no mass-transfer restriction in the main channels of the pores incorporates additional active sites created by metal compounds in the deposited layers and has been shown to have two parameters of the similar type of the Thiele modulus. The model along with lumped reaction kinetics is applied for hydroprocessing reactions in trickle-bed reactors and provides reasonable deactivation curves for desulfurization and demetallation reaction when less than 50% of the original pore volume is filled with metal compounds.

  10. New perspectives on the damage estimation for buried pipeline systems due to seismic wave propagation

    SciTech Connect (OSTI)

    Pineda Porras, Omar Andrey

    2009-01-01

    Over the past three decades, seismic fragility fonnulations for buried pipeline systems have been developed following two tendencies: the use of earthquake damage scenarios from several pipeline systems to create general pipeline fragility functions; and, the use of damage scenarios from one pipeline system to create specific-system fragility functions. In this paper, the advantages and disadvantages of both tendencies are analyzed and discussed; in addition, a summary of what can be considered the new challenges for developing better pipeline seismic fragility formulations is discussed. The most important conclusion of this paper states that more efforts are needed to improve the estimation of transient ground strain -the main cause of pipeline damage due to seismic wave propagation; with relevant advances in that research field, new and better fragility formulations could be developed.

  11. Assessing Fatigue and Ultimate Load Uncertainty in Floating Offshore Wind Turbines Due to Varying Simulation Length

    SciTech Connect (OSTI)

    Stewart, G.; Lackner, M.; Haid, L.; Matha, D.; Jonkman, J.; Robertson, A.

    2013-07-01

    With the push towards siting wind turbines farther offshore due to higher wind quality and less visibility, floating offshore wind turbines, which can be located in deep water, are becoming an economically attractive option. The International Electrotechnical Commission's (IEC) 61400-3 design standard covers fixed-bottom offshore wind turbines, but there are a number of new research questions that need to be answered to modify these standards so that they are applicable to floating wind turbines. One issue is the appropriate simulation length needed for floating turbines. This paper will discuss the results from a study assessing the impact of simulation length on the ultimate and fatigue loads of the structure, and will address uncertainties associated with changing the simulation length for the analyzed floating platform. Recommendations of required simulation length based on load uncertainty will be made and compared to current simulation length requirements.

  12. Does the mass of a black hole decrease due to the accretion of phantom energy?

    SciTech Connect (OSTI)

    Gao Changjun; Chen Xuelei; Faraoni, Valerio; Shen Yougen

    2008-07-15

    According to Babichev et al., the accretion of a phantom test fluid onto a Schwarzschild black hole will induce the mass of the black hole to decrease, however the backreaction was ignored in their calculation. Using new exact solutions describing black holes in a background Friedmann-Robertson-Walker universe, we find that the physical black hole mass may instead increase due to the accretion of phantom energy. If this is the case, and the future universe is dominated by phantom dark energy, the black hole apparent horizon and the cosmic apparent horizon will eventually coincide and, after that, the black hole singularity will become naked in finite comoving time before the big rip occurs, violating the cosmic censorship conjecture.

  13. Structural modifications due to interface chemistry at metal-nitride interfaces

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

    Yadav, S. K.; Shao, S.; Wang, J.; Liu, X. -Y.

    2015-11-27

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. As a result, corresponding to structural energiesmore » of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.« less

  14. Failure of man-made cavities in salt and surface subsidence due to sulfur mining

    SciTech Connect (OSTI)

    Coates, G.K.; Lee, C.A.; McClain, W.C.; Senseny, P.E.

    1981-01-01

    An engineering data base relevant to subsidence due to sulfur mining and to structural failure of cavities in salt is established, evaluated and documented. Nineteen failure events are discussed. Based on these documented failure events, capabilities of and inputs to a mathematical model of cavity failure are determined. Two failure events are adequately documented for use in model verification studies. A conclusion of this study that is pertinent to the Strategic Petroleum Reserve is that cavity failures in dome salt are fairly rare, but that as the number of large cavities (especially those having large roof spans) increases, failures will probably be more common unless stability and failure mechanisms of cavities are better understood.

  15. Structural modifications due to interface chemistry at metal-nitride interfaces

    SciTech Connect (OSTI)

    Yadav, S. K.; Shao, S.; Wang, J.; Liu, X. -Y.

    2015-11-27

    Based on accurate first principles density functional theory (DFT) calculations, an unusual phenomenon of interfacial structural modifications, due to the interface chemistry influence is identified at two metal-nitride interfaces with strong metal-nitrogen affinity, Al/TiN {111} and Al/VN {111} interfaces. It is shown that at such interfaces, a faulted stacking structure is energetically preferred on the Al side of the interface. And both intrinsic and extrinsic stacking fault energies in the vicinity Al layers are negligibly small. However, such phenomenon does not occur in Pt/TiN and Pt/VN interfaces because of the weak Pt-N affinity. As a result, corresponding to structural energies of metal-nitride interfaces, the linear elasticity analysis predicts characteristics of interfacial misfit dislocations at metal-nitride interfaces.

  16. Increased radiation dose at mammography due to prolonged exposure, delayed processing, and increased film darkening

    SciTech Connect (OSTI)

    Kimme-Smith, C.; Bassett, L.W.; Gold, R.H.; Chow, S. )

    1991-02-01

    Four single-emulsion films introduced over the past 2 years--Du Pont Microvision, Fuji MiMa, Konica CM, and Eastman Kodak OM--were compared with Eastman Kodak OM SO-177 (Min-RE) film to evaluate their varying effects on mean glandular dose of reciprocity law failure due to prolonged exposure, delayed processing, and increased film darkening as a result of increased radiation exposure to improve penetration of glandular tissue. Exposures over 1.3 seconds led to increased radiation doses of 20%-30%. Delays in processing of 6 hours decreased processing speed by 11%-32% for all films except Du Pont Microvision. Optical density increases of 0.40 required 20%-30% more skin exposure for all five films. Optimal viewing densities were also evaluated and found to be different for each of the five films. Mammographers need to be aware of these differences in mammographic films to achieve maximum contrast at mammography.

  17. ANALYSIS OF HIGH FIELD NON-LINEAR LOSSES ON SRF SURFACES DUE TO SPECIFIC TOPOGRAPHIC ROUGHNESS

    SciTech Connect (OSTI)

    Chen Xu,Charles Reece,Michael Kelley

    2012-07-01

    The high-field performance of SRF cavities will eventually be limited by the realization of fundamental material limits, whether it is Hc1 or Hsh, or some derivative thereof, at which the superconductivity is lost. Before reaching this fundamental field limit at the macro level, it must be encountered at localized, perhaps microscopic, sites of field enhancement due to local topography. If such sites are small enough, they may produce thermally stabilized normal-conducting regions which contribute non-linear losses when viewed from the macro resonant field perspective, and thus produce degradation in Q0. We have undertaken a calculation of local surface magnetic field enhancement from specific fine topographic structure by conformal mapping method and numerically. A solution of the resulting normal conducting volume has been derived and the corresponding RF Ohmic loss simulated.

  18. Strong Meissner screening change in superconducting radio frequency cavities due to mild baking

    SciTech Connect (OSTI)

    Romanenko, A. Grassellino, A.; Barkov, F.; Suter, A.; Salman, Z.; Prokscha, T.

    2014-02-17

    We investigate “hot” regions with anomalous high field dissipation in bulk niobium superconducting radio frequency cavities for particle accelerators by using low energy muon spin rotation (LE-μSR) on corresponding cavity cutouts. We demonstrate that superconducting properties at the hot region are well described by the non-local Pippard/BCS model for niobium in the clean limit with a London penetration depth λ{sub L}=23±2 nm. In contrast, a cutout sample from the 120 ∘C baked cavity shows a much larger λ>100 nm and a depth dependent mean free path, likely due to gradient in vacancy concentration. We suggest that these vacancies can efficiently trap hydrogen and hence prevent the formation of hydrides responsible for rf losses in hot regions.

  19. Estimation of organ and effective dose due to Compton backscatter security scans

    SciTech Connect (OSTI)

    Hoppe, Michael E.; Schmidt, Taly Gilat

    2012-06-15

    Purpose: To estimate organ and effective radiation doses due to backscatter security scanners using Monte Carlo simulations and a voxelized phantom set. Methods: Voxelized phantoms of male and female adults and children were used with the GEANT4 toolkit to simulate a backscatter security scan. The backscatter system was modeled based on specifications available in the literature. The simulations modeled a 50 kVp spectrum with 1.0 mm-aluminum-equivalent filtration and a previously measured exposure of approximately 4.6 {mu}R at 30 cm from the source. Photons and secondary interactions were tracked from the source until they reached zero kinetic energy or exited from the simulation's boundaries. The energy deposited in the phantoms' respective organs was tallied and used to calculate total organ dose and total effective dose for frontal, rear, and full scans with subjects located 30 and 75 cm from the source. Results: For a full screen, all phantoms' total effective doses were below the established 0.25 {mu}Sv standard, with an estimated maximum total effective dose of 0.07 {mu}Sv for full screen of a male child. The estimated maximum organ dose due to a full screen was 1.03 {mu}Gy, deposited in the adipose tissue of the male child phantom when located 30 cm from the source. All organ dose estimates had a coefficient of variation of less than 3% for a frontal scan and less than 11% for a rear scan. Conclusions: Backscatter security scanners deposit dose in organs beyond the skin. The effective dose is below recommended standards set by the Health Physics Society (HPS) and the American National Standards Institute (ANSI) assuming the system provides a maximum exposure of approximately 4.6 {mu}R at 30 cm.

  20. Stellite 6 Friction Changes Due to Aging and In-Service Testing

    SciTech Connect (OSTI)

    Watkins, John Clifford; DeWall, Kevin George

    2001-07-01

    For the past several years, researchers at the Idaho National Engineering and Environmental Laboratory, under the sponsorship of the U.S. Nuclear Regulatory Commission, have been investigating the ability of motor-operated valves to close or open when subjected to design basis flow and pressure loads. Part of this research addresses the friction that occurs at the interface between the valve disc and the valve body seats during operation of a gate valve. In most gate valves, these surfaces are hardfaced with Stellite 6, a cobalt-based alloy. The nuclear industry has developed methods to analytically predict the thrust needed to operate these valves at specific pressure conditions. To produce accurate valve thrust predictions; the analyst must have a reasonably accurate, though conservative, estimate of the coefficient of friction at the disc-to-seat interface. One of the questions that remains to be answered is whether, and to what extent, aging of the disc and seat surfaces affects the disc-to-seat coefficient of friction. Specifically, does the accumulation of a surface film due to aging of these surfaces increase the coefficient of friction and if so, how much? This paper presents results of specimen tests addressing this issue with emphasis on the following: • The change in the friction coefficient of Stellite 6 as it ages and whether the friction reaches a plateau. • The effect periodic gate valve cycling due to in-service testing has on the friction coefficient. • The results of an independent review of the test methods, processes, and the results of the research to date. • The status of ongoing aging and friction testing.

  1. November 9

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

    9 November 9 PDSF Users Meeting 11/9/10 Attending: Eric, Katie and Jay from NERSC and users Jeff P., Craig, Lisa, Jeff A., Cheng Ju, Marjorie and Maxim. Cluster status: Cluster has been full Up to 1200 cores now. Outages: Yesterday there were GPFS problems related to configuration problems with GPFS on the new nodes. There were also two outages due to security problems. Upcoming downtimes: At some point there will be downtime for home and common replacement. New hardware: eliza 11, 12 and 13 are

  2. Fatigue failure in thin-film polysilicon is due to subcriticalcracking within the oxide layer

    SciTech Connect (OSTI)

    Alsem, D.H.; Muhlstein, C.L.; Stach, E.A.; Ritchie, R.O.

    2005-01-11

    It has been established that microelectromechanical systems (MEMS) created from polycrystalline silicon thin-films are subject to cyclic fatigue. Prior work by the authors has suggested that although bulk silicon is not susceptible to fatigue failure in ambient air, fatigue in micron-scale silicon is a result of a ''reaction-layer'' process, whereby high stresses induce a thickening of the post-release oxide at stress concentrations such as notches, which subsequently undergoes moisture-assisted cracking. However, there exists some controversy regarding the post-release oxide thickness of the samples used in the prior study. In this Letter, we present data from devices from a more recent fabrication run that confirm our prior observations. Additionally, new data from tests in high vacuum show that these devices do not fatigue when oxidation and moisture are suppressed. Each of these observations lends credence to the '''reaction-layer'' mechanism. Recent advances in the design of microelectromechanical systems (MEMS) have increased the demand for more reliable microscale structures. Although silicon is an effective and widely used structural material at the microscale, it is very brittle. Consequently, reliability is a limiting factor for commercial and defense applications. Since the surface to volume ratio of these structural films is very large, classical models for failure modes in bulk materials cannot always be applied. For example, whereas bulk silicon is immune to cyclic fatigue failure thin micron-scale structural films of silicon appear to be highly susceptible. It is clear that at these size scales, surface effects may become dominant in controlling mechanical properties. The main reliability issues for MEMS are stiction, fatigue and wear. Fatigue is important in cases where devices are subjected to a large number of loading cycles with amplitudes below their (single-cycle) fracture stress, which may arise due to vibrations intentionally induced in the

  3. Peripheral Dose Heterogeneity Due to the Thread Effect in Total Marrow Irradiation With Helical Tomotherapy

    SciTech Connect (OSTI)

    Takahashi, Yutaka; Verneris, Michael R.; Dusenbery, Kathryn E.; Wilke, Christopher T.; Storme, Guy; Weisdorf, Daniel J.; Hui, Susanta K.

    2013-11-15

    Purpose: To report potential dose heterogeneity leading to underdosing at different skeletal sites in total marrow irradiation (TMI) with helical tomotherapy due to the thread effect and provide possible solutions to reduce this effect. Methods and Materials: Nine cases were divided into 2 groups based on patient size, defined as maximum left-to-right arm distance (mLRD): small mLRD (≤47 cm) and large mLRD (>47 cm). TMI treatment planning was conducted by varying the pitch and modulation factor while a jaw size (5 cm) was kept fixed. Ripple amplitude, defined as the peak-to-trough dose relative to the average dose due to the thread effect, and the dose–volume histogram (DVH) parameters for 9 cases with various mLRD was analyzed in different skeletal regions at off-axis (eg, bones of the arm or femur), at the central axis (eg, vertebrae), and planning target volume (PTV), defined as the entire skeleton plus 1-cm margin. Results: Average ripple amplitude for a pitch of 0.430, known as one of the magic pitches that reduce thread effect, was 9.2% at 20 cm off-axis. No significant differences in DVH parameters of PTV, vertebrae, or femur were observed between small and large mLRD groups for a pitch of ≤0.287. Conversely, in the bones of the arm, average differences in the volume receiving 95% and 107% dose (V95 and V107, respectively) between large and small mLRD groups were 4.2% (P=.016) and 16% (P=.016), respectively. Strong correlations were found between mLRD and ripple amplitude (rs=.965), mLRD and V95 (rs=−.742), and mLRD and V107 (rs=.870) of bones of the arm. Conclusions: Thread effect significantly influences DVH parameters in the bones of the arm for large mLRD patients. By implementing a favorable pitch value and adjusting arm position, peripheral dose heterogeneity could be reduced.

  4. SSRL BEAM PORT SCHEDULE

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

    5-4 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP DOWN DOWN DOWN DOWN STUP STUP STUP BEAM LINE 8-1 Nov. 09, 2015 Nov. 10, 2015 Nov. 11, 2015 Nov. 12, 2015 Nov. 13, 2015 Nov. 14, 2015 Nov. 15, 2015 DOWN DOWN DOWN DOWN DOWN Unscheduled Unscheduled DOWN DOWN DOWN DOWN Unscheduled Unscheduled Unscheduled DOWN DOWN DOWN DOWN Unscheduled Unscheduled Unscheduled BEAM LINE 8-2 Nov.

  5. Unusual refinery boiler tube failures due to corrosion by sulfuric acid induced by steam leaks

    SciTech Connect (OSTI)

    Lopez-Lopez, D.; Wong-Moreno, A.

    1998-12-31

    Corrosion by sulfuric acid in boilers is a low probability event because gas temperature and metal temperature of boiler tubes are high enough to avoid the condensation of sulfuric acid from flue gases. This degradation mechanism is frequently considered as an important cause of air preheaters materials degradation, where flue gases are cooled by heat transfer to the combustion air. Corrosion is associated to the presence of sulfuric acid, which condensates if metal temperature (or gas temperature) is below of the acid dew point. In economizer tubes, sulfuric acid corrosion is an unlikely event because flue gas and tube temperatures are normally over the acid dewpoint. In this paper, the failure analysis of generator tubes (similar to the economizer of bigger boilers) of two small oil-fired subcritical boilers is reported. It is concluded that sulfuric acid corrosion was the cause of the failure. The sulfuric acid condensation was due to the contact of flue gases containing SO{sub 3} with water-steam spray coming from leaks at the interface of rolled tube to the drum. Considering the information gathered from these two cases studied, an analysis of this failure mechanism is presented including a description of the thermodynamics condition of water leaking from the drum, and an analysis of the factors favoring it.

  6. Measurement of preheat due to fast electrons in laser implosions of cryogenic deuterium targets

    SciTech Connect (OSTI)

    Yaakobi, B.; Stoeckl, C.; Seka, W.; Delettrez, J.A.; Sangster, T.C.; Meyerhofer, D.D.

    2005-06-15

    Preheat due to fast electrons generated by nonlinear laser-plasma interactions can reduce the gain in laser-imploded fusion targets. The first measurements of electron preheat in directly driven, imploding cryogenic-deuterium targets are reported. The preheat level is derived directly from the measured hard-x-ray spectrum. The hard-x-ray detectors were calibrated in situ with a parylene-coated molybdenum solid-sphere target where both the hard x rays and the Mo K{alpha} line were measured. Using electron and radiation transport calculations to relate the measurements to preheat, the fraction of the incident laser energy that preheats the cryogenic deuterium fuel is found to be less than 0.1%, suggesting that preheat will have a negligible impact on target performance. The results are encouraging for the success of planned high-gain direct-drive-ignition experiments on the National Ignition Facility [W. J. Hogan, E. I. Moses, B. E. Warner, M. S. Sorem, and J. M. Soures, Nucl. Fusion 41, 567 (2001)].

  7. Dynamic structural response of reactor-core subassemblies (hexcans) due to accident overpressurization

    SciTech Connect (OSTI)

    Pfeiffer, P.A.; Kulak, R.F.

    1993-08-01

    This paper presents a two-dimensional structural analysis for the evaluation of a single core subassembly due to internal overpressure associated with possible failure of fuel pins having high fission gas plenum pressure. Structural models are developed for the subassemblies and their surroundings with emphasis on the critical physical aspects of the problem. With these models the strains, deformations and the extent of permanent damage (plastic strain) to the subassemblies can be assessed. The nonlinear structural analyses was performed with a finite element program called STRAW (Structural Transient Response of Assembly Wrappers). This finite element program is applicable to nonlinear large displacement problems. The results of this study indicate that the permanent deformation (damage) is strongly influenced by the rise time (time to reach peak pressure) of the pressure pulse and the pressure in the fuel pin. The rise time is influenced by the opening time of the flow path for release of gas from the fuel pin plenum. Several examples are illustrated with various rise times and pressure magnitudes and the resulting permanent deformation of the hexcan wall.

  8. Model for Simulating Dispersion due to Atmospheric Release of UF6

    Energy Science and Technology Software Center (OSTI)

    1997-01-01

    HGSYSTEMUF6 is a suite of models designed for use in estimating consequences associated with accidental, atmospheric release of Uranium Hexafluoride (UF6) and its reaction products, namely Hydrogen Fluoride (HF), and other non-reactive contaminants which are either negatively, neutrally, or positively buoyant. It is based on HGSYSTEM Version 3.0 of Shell Research LTD., and contains specific algorithms for the treatment of UF6 chemistry and thermodynamics. HGSYSTEMUF6 contains algorithms for the treatment of dense gases, dry andmore » wet deposition, effects due to the presence of buildings (canyon and wake), plume lift-off, and the effects of complex terrain. The models components of the suite include (1) AEROPLUME/RK, used to model near-field dispersion from pressurized two-phase jet releases of UF6 and its reaction products, (2) HEGADAS/UF6 for simulating dense, ground based release of UF6, (3) PGPLUME for simulation of passive, neutrally buoyant plumes (4) UF6Mixer for modeling warm, potentially reactive, ground-level releases of UF6 from buildings, and (5) WAKE, used to model elevated and ground-level releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant.« less

  9. Attenuation due to hysteretic damage in the free vibration of a beam

    SciTech Connect (OSTI)

    Mendelsohn, Daniel A.; Pecorari, Claudio

    2014-02-18

    We present an asymptotic analysis of nonlinear free vibration of a beam with a damage plane represented by nonlinear hysteretic bending and shear springs. The perturbation parameter is the product of the ratio of the nonlinear to linear parts of the stiffness times the amplitude of the free vibration. The loss of energy and ensuing attenuation due to hysteresis is accounted for by reducing the amplitude of vibration after each cycle by an amount such that the loss in total system energy equals the work done to traverse the hysteresis loop. A new Fourier representation for each cycle of the hysteresis and the deflection solution is used for this purpose and leads to higher harmonics, an evolving complex stiffness and corrected natural frequency that are linked to the attenuation. The frequency increases to its linear value from an initially reduced value. The damage parameter, frequency shift and fundamental amplitudes are presented as functions of the initial damage parameter and time (cycles of vibration). The amplitudes of several of the higher harmonics are also presented as functions of time. Many of the results exhibit sufficient sensitivity with respect to the damage parameter that they should be able to be used to characterize the damage.

  10. Turbine engine lubricant foaming due to silicone basestock used in non-specification spline lubricant

    SciTech Connect (OSTI)

    Centers, P.W.

    1995-05-01

    Dependent upon molecular weight and distribution, concentration, temperature, air flow, and test details or field application, polydimethylsiloxane (PDMS) may be neutral, profoamant or antifoamant in polyolesters. This understanding was critical in the solution of a turbine engine lubrication system foaming problem occurring at several military locations. Suspect turbine engine-accessory gearbox assembly materials gathered from several sites were evaluated. One non-specification PDMS-based spline lubricant caused copious foaming of the lubricant at less than ten parts-per-million concentration, while a specification polymethyl-phenylsiloxane (PMPS)-based lubricant required a concentration nearly 2000 times greater to generate equivalent foam. Use of the profoamant PDMS spline lubricant was then prohibited. Since prohibition, foaming of turbine engine lubricants used in the particular application has not been reported. PMPS impact on foaming of ester lubricants is similar to a much more viscous PDMS attributed to the reduced interaction of PMPS in esters due to pendant phenyl structure of PMPS absent in PDMS. These data provide significant additional insight and methodology to investigate foaming tendencies of partially miscible silicone-ester and other fluid systems. 7 refs., 2 figs., 1 tab.

  11. Physical property changes in hydrate-bearingsediment due to depressurization and subsequent repressurization

    SciTech Connect (OSTI)

    Kneafsey, Timothy; Waite, W.F.; Kneafsey, T.J.; Winters, W.J.; Mason, D.H.

    2008-06-01

    Physical property measurements of sediment cores containing natural gas hydrate are typically performed on material exposed at least briefly to non-in situ conditions during recovery. To examine effects of a brief excursion from the gas-hydrate stability field, as can occur when pressure cores are transferred to pressurized storage vessels, we measured physical properties on laboratory-formed sand packs containing methane hydrate and methane pore gas. After depressurizing samples to atmospheric pressure, we repressurized them into the methane-hydrate stability field and remeasured their physical properties. Thermal conductivity, shear strength, acoustic compressional and shear wave amplitudes and speeds are compared between the original and depressurized/repressurized samples. X-ray computed tomography (CT) images track how the gas-hydrate distribution changes in the hydrate-cemented sands due to the depressurization/repressurization process. Because depressurization-induced property changes can be substantial and are not easily predicted, particularly in water-saturated, hydrate-bearing sediment, maintaining pressure and temperature conditions throughout the core recovery and measurement process is critical for using laboratory measurements to estimate in situ properties.

  12. THE SIZE DIFFERENCE BETWEEN RED AND BLUE GLOBULAR CLUSTERS IS NOT DUE TO PROJECTION EFFECTS

    SciTech Connect (OSTI)

    Webb, Jeremy J.; Harris, William E.; Sills, Alison

    2012-11-10

    Metal-rich (red) globular clusters in massive galaxies are, on average, smaller than metal-poor (blue) globular clusters. One of the possible explanations for this phenomenon is that the two populations of clusters have different spatial distributions. We test this idea by comparing clusters observed in unusually deep, high signal-to-noise images of M87 with a simulated globular cluster population in which the red and blue clusters have different spatial distributions, matching the observations. We compare the overall distribution of cluster effective radii as well as the relationship between effective radius and galactocentric distance for both the observed and simulated red and blue sub-populations. We find that the different spatial distributions does not produce a significant size difference between the red and blue sub-populations as a whole or at a given galactocentric distance. These results suggest that the size difference between red and blue globular clusters is likely due to differences during formation or later evolution.

  13. Mechanical Deformation of a Lithium-Metal Anode Due to a Very Stiff Separator

    SciTech Connect (OSTI)

    Ferrese, A; Newman, J

    2014-05-21

    This work builds on the two-dimensional model presented by Ferrese et al. [J. Electrochem. Soc., 159, A1615 (2012)1, which captures the movement of lithium metal at the negative electrode during cycling in a Li-metal/LiCoO2 cell. In this paper, the separator is modeled as a dendrite-inhibiting polymer separator with an elastic modulus of 16 GPa. The separator resists the movement of lithium through the generation of stresses in the cell. These stresses affect the negative electrode through two mechanisms altering the thermodynamics of the negative electrode and deforming the negative electrode mechanically. From this analysis, we find that the dendrite-inhibiting separator causes plastic and elastic deformation of the lithium at the negative electrode which flattens the electrode considerably when compared to the liquid-electrolyte case. This flattening of the negative electrode causes only very slight differences in the local state of charge in the positive electrode. When comparing the magnitude of the effects flattening the negative electrode, we find that the plastic deformation plays a much larger role than either the pressure-modified reaction kinetics or elastic deformation. This is due to the low yield strength of the lithium metal, which limits the stresses such that they have only a small effect on the reaction kinetics. (C) 2014 The Electrochemical Society. All rights reserved.

  14. Deterioration of Pracana Dam due to ASR. Main features and repair works

    SciTech Connect (OSTI)

    Matos, D.S.; Camelo, S.; Silva, H.S.; Pinho, J.S.

    1995-12-31

    Some of the Portuguese concrete dams show evidences of ASR. In majority the phenomena is still benign. However, in a few cases some significant deterioration of ASR type have malfunctions arose. In such cases deteriorations of ASR type have been detected while in the others the ASSR type prevail, depending on the type of aggregate. The paper reports the most important case of ASR in Portuguese concrete dams. Pracana dam is a buttress structures built in 1948-51, being the aggregates predominantly of quartzitic and metapellitic nature. Subsequently to the intense fracturing due to a quick concrete cooling during the first filling of the reservoir, high levels of expansion rates had been detected by means of monitoring system. After 8 years emptied reservoir, rehabilitation works took place in 1991-92 aiming at the concrete mass regeneration and the installation of an upstream face membrane, the improvement of spillway capacity and of the foundation performances. The behaviour of the dam as well as the performed tests (petrographic, mechanic, ultrasonic and expansibility ones) and repair works are described in the paper.

  15. FARADAY ROTATION MEASURE DUE TO THE INTERGALACTIC MAGNETIC FIELD. II. THE COSMOLOGICAL CONTRIBUTION

    SciTech Connect (OSTI)

    Akahori, Takuya; Ryu, Dongsu E-mail: ryu@canopus.cnu.ac.kr

    2011-09-10

    We investigate the Faraday rotation measure (RM) due to the intergalactic magnetic field (IGMF) through the cosmic web up to cosmological distances, using a model IGMF based on turbulence dynamo in the large-scale structure of the universe. By stacking the IGMF and gas density data up to redshift z = 5 and taking account of the redshift distribution of polarized background radio sources against which the RM is measured, we simulate the sky map of the RM. The contribution from galaxy clusters is subtracted from the map, based on several different criteria of X-ray brightness and temperature. Our findings are as follows. The distribution of RM for radio sources of different redshifts shows that the rms value increases with redshift and saturates for z {approx}> 1. The saturated value is RM{sub rms} {approx} several rad m{sup -2}. The probability distribution function of |RM| follows the lognormal distribution. The power spectrum has a broad plateau over the angular scale of {approx}1{sup 0}-0.{sup 0}1 with a peak around {approx}0.{sup 0}15. The second-order structure function has a flat profile in the angular separation of {approx}> 0.{sup 0}2. Our results could provide useful insights for surveys to explore the IGMF with the Square Kilometer Array (SKA) and upcoming SKA pathfinders.

  16. RADIOLOGICAL RELEASES DUE TO AIR AND SILICA DUST ACTIVATION IN EMPLACEMENT DRIFTS

    SciTech Connect (OSTI)

    J.S. Tang

    2003-05-07

    The purpose of this calculation is to determine the quantity and significance of annual Monitored Geologic Repository (MGR) subsurface normal radiological releases due to neutron activation of air and silica dust in emplacement drifts. This calculation includes the following items: (1) Calculate activation of ventilation airflow through emplacement drifts to quantify radioactive gaseous releases; and (2) Calculate the bounding potential activated silica dust concentration and releases. The sources of silica dust may arise from air supply to emplacement drifts as well as host rock around emplacement drifts. For this calculation, the source of dust is conservatively assumed to be the host rock (Assumption 3.6), which is subject to long-term neutron exposure resulting in saturated radioactivity. The scope of this calculation is limited to releases from activated air and silica dust only, excluding natural radioactive releases such as radon or releases from defective waste packages (breached or contaminated). This work supports the repository ventilation system design and Preclosure Safety Analysis. This includes MGR items classified as Quality Level 1, for example, the Uncanistered Spent Nuclear Fuel Waste Package (CRWMS M&O [Civilian Radioactive Waste Management and Operation Contractor] 1999a, page 7). Therefore, this calculation is subject to the requirements of the ''Quality Assurance Requirements and Description'' (DOE [U.S. Department of Energy] 2003). The performance of the calculation and development of this document are carried out in accordance with AP-3.12Q, ''Design Calculation and Analyses'' and LP-3.30Q-BSC, ''Hazards Analysis System''.

  17. An opposite view data replacement approach for reducing artifacts due to metallic dental objects

    SciTech Connect (OSTI)

    Yazdi, Mehran; Lari, Meghdad Asadi; Bernier, Gaston; Beaulieu, Luc

    2011-04-15

    Purpose: To present a conceptually new method for metal artifact reduction (MAR) that can be used on patients with multiple objects within the scan plane that are also of small sized along the longitudinal (scanning) direction, such as dental fillings. Methods: The proposed algorithm, named opposite view replacement, achieves MAR by first detecting the projection data affected by metal objects and then replacing the affected projections by the corresponding opposite view projections, which are not affected by metal objects. The authors also applied a fading process to avoid producing any discontinuities in the boundary of the affected projection areas in the sinogram. A skull phantom with and without a variety of dental metal inserts was made to extract the performance metric of the algorithm. A head and neck case, typical of IMRT planning, was also tested. Results: The reconstructed CT images based on this new replacement scheme show a significant improvement in image quality for patients with metallic dental objects compared to the MAR algorithms based on the interpolation scheme. For the phantom, the authors showed that the artifact reduction algorithm can efficiently recover the CT numbers in the area next to the metallic objects. Conclusions: The authors presented a new and efficient method for artifact reduction due to multiple small metallic objects. The obtained results from phantoms and clinical cases fully validate the proposed approach.

  18. HGSYSTEMUF6. Model for Simulating Dispersion due to Atmospheric Release of UF6

    SciTech Connect (OSTI)

    Hanna, G; Chang, J.C.; Zhang, J.X.; Bloom, S.G.; Goode, W.D. Jr; Lombardi, D.A.; Yambert, M.W.

    1998-08-01

    HGSYSTEMUF6 is a suite of models designed for use in estimating consequences associated with accidental, atmospheric release of Uranium Hexafluoride (UF6) and its reaction products, namely Hydrogen Fluoride (HF), and other non-reactive contaminants which are either negatively, neutrally, or positively buoyant. It is based on HGSYSTEM Version 3.0 of Shell Research LTD., and contains specific algorithms for the treatment of UF6 chemistry and thermodynamics. HGSYSTEMUF6 contains algorithms for the treatment of dense gases, dry and wet deposition, effects due to the presence of buildings (canyon and wake), plume lift-off, and the effects of complex terrain. The models components of the suite include (1) AEROPLUME/RK, used to model near-field dispersion from pressurized two-phase jet releases of UF6 and its reaction products, (2) HEGADAS/UF6 for simulating dense, ground based release of UF6, (3) PGPLUME for simulation of passive, neutrally buoyant plumes (4) UF6Mixer for modeling warm, potentially reactive, ground-level releases of UF6 from buildings, and (5) WAKE, used to model elevated and ground-level releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant.

  19. ANALYSIS OF DISTRIBUTION FEEDER LOSSES DUE TO ADDITION OF DISTRIBUTED PHOTOVOLTAIC GENERATORS

    SciTech Connect (OSTI)

    Tuffner, Francis K.; Singh, Ruchi

    2011-08-09

    Distributed generators (DG) are small scale power supplying sources owned by customers or utilities and scattered throughout the power system distribution network. Distributed generation can be both renewable and non-renewable. Addition of distributed generation is primarily to increase feeder capacity and to provide peak load reduction. However, this addition comes with several impacts on the distribution feeder. Several studies have shown that addition of DG leads to reduction of feeder loss. However, most of these studies have considered lumped load and distributed load models to analyze the effects on system losses, where the dynamic variation of load due to seasonal changes is ignored. It is very important for utilities to minimize the losses under all scenarios to decrease revenue losses, promote efficient asset utilization, and therefore, increase feeder capacity. This paper will investigate an IEEE 13-node feeder populated with photovoltaic generators on detailed residential houses with water heater, Heating Ventilation and Air conditioning (HVAC) units, lights, and other plug and convenience loads. An analysis of losses for different power system components, such as transformers, underground and overhead lines, and triplex lines, will be performed. The analysis will utilize different seasons and different solar penetration levels (15%, 30%).

  20. Underground Infrastructure Impacts Due to a Surface Burst Nuclear Device in an Urban Canyon Environment

    SciTech Connect (OSTI)

    Bos, Randall J.; Dey, Thomas N.; Runnels, Scott R.

    2012-07-03

    Investigation of the effects of a nuclear device exploded in a urban environment such as the Chicago studied for this particular report have shown the importance on the effects from the urban canyons so typical of today's urban environment as compared to nuclear test event effects observed at the Nevada Test Site (NTS) and the Pacific Testing Area on which many of the typical legacy empirical codes are based on. This report first looks at the some of the data from nuclear testing that can give an indication of the damage levels that might be experienced due to a nuclear event. While it is well known that a above ground blast, even a ground burst, very poorly transmits energy into the ground ( < 1%) and the experimental results discussed here are for fully coupled detonations, these results do indicate a useful measure of the damage that might be expected. The second part of the report looks at effects of layering of different materials that typically would make up the near ground below surface environment that a shock would propagate through. As these simulations support and is widely known in the community, the effects of different material compositions in these layers modify the shock behavior and especially modify the energy dispersal and coupling into the basement structures. The third part of the report looks at the modification of the underground shock effects from a surface burst 1 KT device due to the presence of basements under the Chicago buildings. Without direct knowledge of the basement structure, a simulated footprint of a uniform 20m depth was assumed underneath each of the NGI defined buildings in the above ground environment. In the above ground case, the underground basement structures channel the energy along the line of site streets keeping the shock levels from falling off as rapidly as has been observed in unobstructed detonations. These simulations indicate a falloff of factors of 2 per scaled length as compared to 10 for the unobstructed

  1. Escape fraction of ionizing photons during reionization: Effects due to supernova feedback and runaway ob stars

    SciTech Connect (OSTI)

    Kimm, Taysun; Cen, Renyue

    2014-06-20

    The fraction of hydrogen ionizing photons escaping from galaxies into the intergalactic medium is a critical ingredient in the theory of reionization. We use two zoomed-in, high-resolution (4 pc), cosmological radiation hydrodynamic simulations with adaptive mesh refinement to investigate the impact of two physical mechanisms (supernova, SN, feedback, and runaway OB stars) on the escape fraction (f {sub esc}) at the epoch of reionization (z ? 7). We implement a new, physically motivated SN feedback model that can approximate the Sedov solutions at all (from the free expansion to snowplow) stages. We find that there is a significant time delay of about ten million years between the peak of star formation and that of escape fraction, due to the time required for the build-up and subsequent destruction of the star-forming cloud by SN feedback. Consequently, the photon number-weighted mean escape fraction for dwarf galaxies in halos of mass 10{sup 8}-10{sup 10.5} M {sub ?} is found to be ?f{sub esc}??11%, although instantaneous values of f {sub esc} > 20% are common when star formation is strongly modulated by the SN explosions. We find that the inclusion of runaway OB stars increases the mean escape fraction by 22% to ?f{sub esc}??14%. As SNe resulting from runaway OB stars tend to occur in less dense environments, the feedback effect is enhanced and star formation is further suppressed in halos with M{sub vir}?10{sup 9} M{sub ?} in the simulation with runaway OB stars compared with the model without them. While both our models produce enough ionizing photons to maintain a fully ionized universe at z ? 7 as observed, a still higher amount of ionizing photons at z ? 9 appears necessary to accommodate the high observed electron optical depth inferred from cosmic microwave background observations.

  2. SPECTRUM-DRIVEN PLANETARY DEGLACIATION DUE TO INCREASES IN STELLAR LUMINOSITY

    SciTech Connect (OSTI)

    Shields, Aomawa L.; Meadows, Victoria S.; Bitz, Cecilia M.; Joshi, Manoj M.; Robinson, Tyler D.

    2014-04-10

    Distant planets in globally ice-covered, ''snowball'', states may depend on increases in their host stars' luminosity to become hospitable for surface life. Using a general circulation model, we simulated the equilibrium climate response of a planet to a range of instellations from an F-, G-, or M-dwarf star. The range of instellation that permits both complete ice cover and at least partially ice-free climate states is a measure of the climate hysteresis that a planet can exhibit. An ice-covered planet with high climate hysteresis would show a higher resistance to the initial loss of surface ice coverage with increases in instellation, and abrupt, extreme ice loss once deglaciation begins. Our simulations indicate that the climate hysteresis depends sensitively on the host star spectral energy distribution. Under fixed CO{sub 2} conditions, a planet orbiting an M-dwarf star exhibits a smaller climate hysteresis, requiring smaller instellation to initiate deglaciation than planets orbiting hotter, brighter stars. This is due to the higher absorption of near-infrared radiation by ice on the surfaces and greenhouse gases and clouds in the atmosphere of an M-dwarf planet. Increases in atmospheric CO{sub 2} further lower the climate hysteresis, as M-dwarf snowball planets exhibit a larger radiative response than G-dwarf snowball planets for the same increase in CO{sub 2}. For a smaller hysteresis, planets near the outer edge of the habitable zone will thaw earlier in their evolutionary history, and will experience a less abrupt transition out of global ice cover.

  3. IMPLICATIONS OF MASS AND ENERGY LOSS DUE TO CORONAL MASS EJECTIONS ON MAGNETICALLY ACTIVE STARS

    SciTech Connect (OSTI)

    Drake, Jeremy J.; Cohen, Ofer; Yashiro, Seiji; Gopalswamy, Nat

    2013-02-20

    Analysis of a database of solar coronal mass ejections (CMEs) and associated flares over the period 1996-2007 finds well-behaved power-law relationships between the 1-8 A flare X-ray fluence and CME mass and kinetic energy. We extrapolate these relationships to lower and higher flare energies to estimate the mass and energy loss due to CMEs from stellar coronae, assuming that the observed X-ray emission of the latter is dominated by flares with a frequency as a function of energy dn/dE = kE {sup -{alpha}}. For solar-like stars at saturated levels of X-ray activity, the implied losses depend fairly weakly on the assumed value of {alpha} and are very large: M-dot {approx}5 Multiplication-Sign 10{sup -10} M{sub sun} yr{sup -1} and E-dot {approx}0.1 L{sub sun}. In order to avoid such large energy requirements, either the relationships between CME mass and speed and flare energy must flatten for X-ray fluence {approx}> 10{sup 31} erg, or the flare-CME association must drop significantly below 1 for more energetic events. If active coronae are dominated by flares, then the total coronal energy budget is likely to be up to an order of magnitude larger than the canonical 10{sup -3} L {sub bol} X-ray saturation threshold. This raises the question of what is the maximum energy a magnetic dynamo can extract from a star? For an energy budget of 1% of L {sub bol}, the CME mass loss rate is about 5 Multiplication-Sign 10{sup -11} M {sub Sun} yr{sup -1}.

  4. Mapping and Simulating Systematics Due to Spatially-Varying Observing Conditions in DES Science Verification Data

    SciTech Connect (OSTI)

    Leistedt, B.

    2015-07-20

    Spatially-varying depth and characteristics of observing conditions, such as seeing, airmass, or sky background, are major sources of systematic uncertainties in modern galaxy survey analyses, in particular in deep multi-epoch surveys. We present a framework to extract and project these sources of systematics onto the sky, and apply it to the Dark Energy Survey (DES) to map the observing conditions of the Science Verification (SV) data. The resulting distributions and maps of sources of systematics are used in several analyses of DES SV to perform detailed null tests with the data, and also to incorporate systematics in survey simulations. We illustrate the complementarity of these two approaches by comparing the SV data with the BCC-UFig, a synthetic sky catalogue generated by forward-modelling of the DES SV images. We then analyse the BCC-UFig simulation to construct galaxy samples mimicking those used in SV galaxy clustering studies. We show that the spatially-varying survey depth imprinted in the observed galaxy densities and the redshift distributions of the SV data are successfully reproduced by the simulation and well-captured by the maps of observing conditions. The combined use of the maps, the SV data and the BCC-UFig simulation allows us to quantify the impact of spatial systematics on N(z), the redshift distributions inferred using photometric redshifts. We conclude that spatial systematics in the SV data are mainly due to seeing fluctuations and are under control in current clustering and weak lensing analyses. However, they will need to be carefully characterised in upcoming phases of DES in order to avoid biasing the inferred cosmological results. The framework presented is relevant to all multi-epoch surveys, and will be essential for exploiting future surveys such as the Large Synoptic Survey Telescope, which will require detailed null-tests and realistic end-to-end image simulations to correctly interpret the deep, high-cadence observations of the

  5. Quantifying Unnecessary Normal Tissue Complication Risks due to Suboptimal Planning: A Secondary Study of RTOG 0126

    SciTech Connect (OSTI)

    Moore, Kevin L.; Schmidt, Rachel; Moiseenko, Vitali; Olsen, Lindsey A.; Tan, Jun; Xiao, Ying; Galvin, James; Pugh, Stephanie; Seider, Michael J.; Dicker, Adam P.; Bosch, Walter; Michalski, Jeff; Mutic, Sasa

    2015-06-01

    predicted NTCP reductions while maintaining the volume of the PTV receiving prescription dose. An equivalent sample of high-quality plans showed fewer toxicities than low-quality plans, 6 of 73 versus 10 of 73 respectively, although these differences were not significant (P=.21) due to insufficient statistical power in this retrospective study. Conclusions: Plan quality deficiencies in RTOG 0126 exposed patients to substantial excess risk for rectal complications.

  6. Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

    SciTech Connect (OSTI)

    Rawl, Richard R; Scofield, Patricia A; Leggett, Richard Wayne; Eckerman, Keith F

    2010-04-01

    The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low-level NORM

  7. INITIAL ANALYSIS OF TRANSIENT POWER TIME LAG DUE TO HETEROGENEITY WITHIN THE TREAT FUEL MATRIX.

    SciTech Connect (OSTI)

    D.M. Wachs; A.X. Zabriskie, W.R. Marcum

    2014-06-01

    The topic Nuclear Safety encompasses a broad spectrum of focal areas within the nuclear industry; one specific aspect centers on the performance and integrity of nuclear fuel during a reactivity insertion accident (RIA). This specific accident has proven to be fundamentally difficult to theoretically characterize due to the numerous empirically driven characteristics that quantify the fuel and reactor performance. The Transient Reactor Test (TREAT) facility was designed and operated to better understand fuel behavior under extreme (i.e. accident) conditions; it was shutdown in 1994. Recently, efforts have been underway to commission the TREAT facility to continue testing of advanced accident tolerant fuels (i.e. recently developed fuel concepts). To aid in the restart effort, new simulation tools are being used to investigate the behavior of nuclear fuels during facility’s transient events. This study focuses specifically on the characterizing modeled effects of fuel particles within the fuel matrix of the TREAT. The objective of this study was to (1) identify the impact of modeled heterogeneity within the fuel matrix during a transient event, and (2) demonstrate acceptable modeling processes for the purpose of TREAT safety analyses, specific to fuel matrix and particle size. Hypothetically, a fuel that is dominantly heterogeneous will demonstrate a clearly different temporal heating response to that of a modeled homogeneous fuel. This time difference is a result of the uniqueness of the thermal diffusivity within the fuel particle and fuel matrix. Using MOOSE/BISON to simulate the temperature time-lag effect of fuel particle diameter during a transient event, a comparison of the average graphite moderator temperature surrounding a spherical particle of fuel was made for both types of fuel simulations. This comparison showed that at a given time and with a specific fuel particle diameter, the fuel particle (heterogeneous) simulation and the homogeneous simulation

  8. Key factors for determining groundwater impacts due to leakage from geologic carbon sequestration reservoirs

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

    Carroll, Susan A.; Keating, Elizabeth; Mansoor, Kayyum; Dai, Zhenxue; Sun, Yunwei; Trainor-Guitton, Whitney; Brown, Chris; Bacon, Diana

    2014-09-07

    The National Risk Assessment Partnership (NRAP) is developing a science-based toolset for the analysis of potential impacts to groundwater chemistry from CO2 injection (www.netldoe.gov/nrap). The toolset adopts a stochastic approach in which predictions address uncertainties in shallow groundwater and leakage scenarios. It is derived from detailed physics and chemistry simulation results that are used to train more computationally efficient models, referred to here as reduced-order models (ROMs), for each component system. In particular, these tools can be used to help regulators and operators understand the expected sizes and longevity of plumes in pH, TDS, and dissolved metals that could resultmore » from a leakage of brine and/or CO2 from a storage reservoir into aquifers. This information can inform, for example, decisions on monitoring strategies that are both effective and efficient. We have used this approach to develop predictive reduced-order models for two common types of reservoirs, but the approach could be used to develop a model for a specific aquifer or other common types of aquifers. In this paper we describe potential impacts to groundwater quality due to CO2 and brine leakage, discuss an approach to calculate thresholds under which no impact to groundwater occurs, describe the time scale for impact on groundwater, and discuss the probability of detecting a groundwater plume should leakage occur. To facilitate this, multi-phase flow and reactive transport simulations and emulations were developed for two classes of aquifers, considering uncertainty in leakage source terms and aquifer hydrogeology. We targeted an unconfined fractured carbonate aquifer based on the Edwards aquifer in Texas and a confined alluvium aquifer based on the High Plains Aquifer in Kansas, which share characteristics typical of many drinking water aquifers in the United States. The hypothetical leakage scenarios centered on the notion that wellbores are the most likely

  9. Key factors for determining groundwater impacts due to leakage from geologic carbon sequestration reservoirs

    SciTech Connect (OSTI)

    Carroll, Susan A.; Keating, Elizabeth; Mansoor, Kayyum; Dai, Zhenxue; Sun, Yunwei; Trainor-Guitton, Whitney; Brown, Chris; Bacon, Diana

    2014-09-07

    The National Risk Assessment Partnership (NRAP) is developing a science-based toolset for the analysis of potential impacts to groundwater chemistry from CO2 injection (www.netldoe.gov/nrap). The toolset adopts a stochastic approach in which predictions address uncertainties in shallow groundwater and leakage scenarios. It is derived from detailed physics and chemistry simulation results that are used to train more computationally efficient models, referred to here as reduced-order models (ROMs), for each component system. In particular, these tools can be used to help regulators and operators understand the expected sizes and longevity of plumes in pH, TDS, and dissolved metals that could result from a leakage of brine and/or CO2 from a storage reservoir into aquifers. This information can inform, for example, decisions on monitoring strategies that are both effective and efficient. We have used this approach to develop predictive reduced-order models for two common types of reservoirs, but the approach could be used to develop a model for a specific aquifer or other common types of aquifers. In this paper we describe potential impacts to groundwater quality due to CO2 and brine leakage, discuss an approach to calculate thresholds under which no impact to groundwater occurs, describe the time scale for impact on groundwater, and discuss the probability of detecting a groundwater plume should leakage occur. To facilitate this, multi-phase flow and reactive transport simulations and emulations were developed for two classes of aquifers, considering uncertainty in leakage source terms and aquifer hydrogeology. We targeted an unconfined fractured carbonate aquifer based on the Edwards aquifer in Texas and a confined alluvium aquifer based on the High Plains Aquifer in Kansas, which share characteristics typical of many drinking water aquifers in the United States. The hypothetical leakage scenarios centered on the notion that wellbores

  10. RECONSTRUCTION OF INDIVIDUAL DOSES DUE TO MEDICAL EXPOSURES FOR MEMBERS OF THE TECHA RIVER COHORT

    SciTech Connect (OSTI)

    Shagina, N. B.; Golikov, V.; Degteva, M. O.; Vorobiova, M. I.; Anspaugh, L. R.; Napier, Bruce A.

    2012-11-01

    Purpose: To describe a methodology for reconstruction of doses due to medical exposures for members of the Techa River Cohort (TRC) who received diagnostic radiation at the clinic of the Urals Research Center for Radiation Medicine (URCRM) in 19522005. To calculate doses of medical exposure for the TRC members and compare with the doses that resulted from radioactive contamination of the Techa River. Material and Methods: Reconstruction of individual medical doses is based on data on x-ray diagnostic procedures available for each person examined at the URCRM clinics and values of absorbed dose in 12 organs per typical x-ray procedure calculated with the use of a mathematical phantom. Personal data on x-ray diagnostic examinations have been complied in the computerized Registry of x-ray diagnostic procedures. Sources of information are archival registry books from the URCRM x-ray room (available since 1956) and records on x-ray diagnostic procedures in patient-case histories (since 1952). The absorbed doses for 12 organs of interest have been evaluated per unit typical x-ray procedure with account taken of the x-ray examination parameters characteristic for the diagnostic machines used at the URCRM clinics. These parameters have been evaluated from published data on technical characteristics of the x-ray diagnostic machines used at the URCRM clinics in 19521988 and taken from the x-ray room for machines used at the URCRM in 19892005. Absorbed doses in the 12 organs per unit typical x-ray procedure have been calculated with use of a special computer code, EDEREX, developed at the Saint-Petersburg Research Institute of Radiation Hygiene after Professor P.V. Ramzaev. Individual accumulated doses of medical exposure have been calculated with a computer code, MEDS (Medical Exposure Dosimetry System), specifically developed at the URCRM. Results: At present, the Registry of x-ray diagnostic procedures contains information on individual x-ray examinations for over 9

  11. Fact #775: April 15, 2013 Top Ten Urban Areas for Fuel Wasted due to Traffic Congestion, 2011

    Broader source: Energy.gov [DOE]

    The top ten urban areas across the U.S. accounted for nearly 40% of the total fuel wasted due to traffic congestion in 2011. Highway congestion caused vehicles in the combined urban areas of New...

  12. Effect of the magnetic lenses on the electron current due to near wall conductivity in a Hall thruster

    SciTech Connect (OSTI)

    Wu Zhiwen; Liu Xiangyang; Wang Ningfei; Yu Daren

    2010-07-15

    The effect of magnetic lens on the electron current due to near wall conductivity (NWC) in a Hall thruster is studied. A Monte Carlo model is employed to simulate the effect of the large magnetic field incidence angle on the electron current. The simulation results show that the electron current due to NWC decreases in the case of large incidence. The simulation qualitatively agrees with the related experimental result. And the simulation also demonstrates that choosing the curvature angle of the magnetic field is also a key factor to design a Hall thruster with high operation performance.

  13. CT-Guided Percutaneous Drainage of Infected Collections Due to Gastric Leak After Sleeve Gastrectomy for Morbid Obesity: Initial Experience

    SciTech Connect (OSTI)

    Kelogrigoris, M. Sotiropoulou, E.; Stathopoulos, K.; Georgiadou, V.; Philippousis, P.; Thanos, L.

    2011-06-15

    This study was designed to evaluate the efficacy and safety of computed tomography (CT)-guided drainage in treating infected collections due to gastric leak after laparoscopic sleeve gastrectomy for morbid obesity. From January 2007 to June 2009, 21 patients (9 men and 12 women; mean age, 39.2 (range, 26-52) years) with infected collections due to gastric leak after laparoscopic sleeve gastrectomy for morbid obesity underwent image-guided percutaneous drainage. All procedures were performed using CT guidance and 8- to 12-Fr pigtail drainage catheters. Immediate technical success was achieved in all 21 infected collections. In 18 of 21 collections, we obtained progressive shrinkage of the collection with consequent clinical success (success rate 86%). In three cases, the abdominal fluid collection was not resolved, and the patients were reoperated. Among the 18 patients who avoided surgery, 2 needed replacement of the catheter due to obstruction. No major complications occurred during the procedure. The results of our study support that CT-guided percutaneous drainage is an effective and safe method to treat infected abdominal fluid collections due to gastric leak in patients who had previously underwent laparoscopic sleeve gastrectomy for morbid obesity. It may be considered both as a preparatory step for surgery and a valuable alternative to open surgery. Failure of the procedure does not, however, preclude a subsequent surgical operation.

  14. Untitled Page

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

    Environmental Reporting Requirements (To filter the table, type a word or phrase in the boxes below that corresponds with the column you would like to filter. Example, in the box above Report type "monitoring", then select the Go button or use the Enter key on your keyboard) (To reset your filter delete the contents from the boxes and select the Go button or the Enter key) Reporting Mechanism Scheduled or Unscheduled Reporting Notification or Other Frequency Due Date Origin of

  15. Evaluation of flow redistribution due to flow blockage in rod bundles using COBRA code simulation. Final report. [PWR

    SciTech Connect (OSTI)

    Prelewicz, D.A.; Caruso, M.A.

    1981-01-01

    During a Loss-of-Coolant Accident, fuel rod cladding may reach temperatures approaching 2200/sup 0/F. At these temperatures, swelling and rupture of the cladding may occur. The resulting flow blockage will affect steam flow and heat transfer in the bundle during the period of reflooding. The COBRA-IV-I subchannel computer code was used to simulate flow redistribution due to sleeve blockages in the FLECHT-SEASET 21-rod bundle and plate blockages in the JAERI Slab Core Test Facility. Sensitivity studies were conducted to determine the effects of spacer grid and blockage interaction, sleeve shape effects, sleeve length effects, blockage magnitude and distribution, thermally induced mixing and bundle average velocity on flow redistribution. Pressure drop due to sleeve blockages was also calculated for several blockage configurations.

  16. Effect of the plasma shapes on intrinsic rotation due to collisionless ion orbit loss in the tokamak edge plasmas

    SciTech Connect (OSTI)

    Ou, Jing; Wu, Guojiang; Li, Xinxia

    2014-07-15

    Distribution of the intrinsic rotation due to collisionless ion orbit loss near the tokamak edge region is studied by using an analytical model based on ion guiding center orbit approximation. A peak of the averaged ion orbit loss momentum fraction is found very near inside the separatrix region in a double null divertor configuration but is not found inside the last closed flux surface region in an outer limiter configuration. For the double null divertor configuration, the intrinsic rotation due to ion orbit loss depends on the plasma shape. With the increase in elongation and triangularity, the peak of the averaged ion orbit loss momentum fraction increases and it moves inward for the lower plasma current.

  17. Uncertainty in soil-structure interaction analysis of a nuclear power plant due to different analytical techniques

    SciTech Connect (OSTI)

    Chen, J.C.; Chun, R.C.; Goudreau, G.L.; Maslenikov, O.R.; Johnson, J.J.

    1984-01-01

    This paper summarizes the results of the dynamic response analysis of the Zion reactor containment building using three different soil-structure interaction (SSI) analytical procedures which are: the substructure method, CLASSI; the equivalent linear finite element approach, ALUSH; and the nonlinear finite element procedure, DYNA3D. Uncertainties in analyzing a soil-structure system due to SSI analysis procedures were investigated. Responses at selected locations in the structure were compared through peak accelerations and response spectra.

  18. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration

    SciTech Connect (OSTI)

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-10-09

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variation of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. We find these results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images.

  19. Image reconstruction in higher dimensions: myocardial perfusion imaging of tracer dynamics with cardiac motion due to deformation and respiration

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

    Shrestha, Uttam M.; Seo, Youngho; Botvinick, Elias H.; Gullberg, Grant T.

    2015-10-09

    Myocardial perfusion imaging (MPI) using slow rotating large field of view cameras requires spatiotemporal reconstruction of dynamically acquired data to capture the time variation of the radiotracer concentration. In vivo, MPI contains additional degrees of freedom involving unavoidable motion of the heart due to quasiperiodic beating and the effects of respiration, which can severely degrade the quality of the images. This work develops a technique for a single photon emission computed tomography (SPECT) that reconstructs the distribution of the radiotracer concentration in the myocardium using a tensor product of different sets of basis functions that approximately describe the spatiotemporal variationmore » of the radiotracer concentration and the motion of the heart. In this study the temporal B-spline basis functions are chosen to reflect the dynamics of the radiotracer, while the intrinsic deformation and the extrinsic motion of the heart are described by a product of a discrete set of Gaussian basis functions. Reconstruction results are presented showing the dynamics of the tracer in the myocardium as it deforms due to cardiac beating, and is displaced due to respiratory motion. We find these results are compared with the conventional 4D-spatiotemporal reconstruction method that models only the temporal changes of the tracer activity. The higher dimensional reconstruction method proposed here improves bias, yet the signal-to-noise ratio (SNR) decreases slightly due to redistribution of the counts over the cardiac-respiratory gates. Additionally, there is a trade-off between the number of gates and the number of projections per gate to achieve high contrast images.« less

  20. Poster — Thur Eve — 77: Implanted Brachythearpy Seed Movement due to Transrectal Ultrasound Probe-Induced Prostate Deformation

    SciTech Connect (OSTI)

    Liu, D; Usmani, N; Sloboda, R; Meyer, T; Husain, S; Angyalfi, S; Kay, I

    2014-08-15

    The study investigated the movement of implanted brachytherapy seeds upon transrectal US probe removal, providing insight into the underlying prostate deformation and an estimate of the impact on prostate dosimetry. Implanted seed distributions, one obtained with the prostate under probe compression and another with the probe removed, were reconstructed using C-arm fluoroscopy imaging. The prostate, delineated on ultrasound images, was registered to the fluoroscopy images using seeds and needle tracks identified on ultrasound. A deformation tensor and shearing model was developed to correlate probe-induced seed movement with position. Changes in prostate TG-43 dosimetry were calculated. The model was used to infer the underlying prostate deformation and to estimate the location of the prostate surface in the absence of probe compression. Seed movement patterns upon probe removal reflected elastic decompression, lateral shearing, and rectal bending. Elastic decompression was characterized by expansion in the anterior-posterior direction and contraction in the superior-inferior and lateral directions. Lateral shearing resulted in large anterior movement for extra-prostatic seeds in the lateral peripheral region. Whole prostate D90 increased up to 8 Gy, mainly due to the small but systematic seed movement associated with elastic decompression. For selected patients, lateral shearing movement increased prostate D90 by 4 Gy, due to increased dose coverage in the anterior-lateral region at the expense of the posterior-lateral region. The effect of shearing movement on whole prostate D90 was small compared to elastic decompression due to the subset of peripheral seeds involved, but is expected to have greater consequences for local dose coverage.

  1. Enhanced excitonic photoconductivity due to built-in internal electric field in TlGaSe{sub 2} layered semiconductor

    SciTech Connect (OSTI)

    Seyidov, MirHasan Yu. Suleymanov, Rauf A.; ?ale, Yasin; Balaban, Ertan

    2014-12-07

    The strong enhancement, by several orders of magnitude, of the excitonic peak within the photoconductivity spectrum of TlGaSe{sub 2} semiconductor was observed. The samples were polarized in external dc electric field, which was applied prior to the measurements. Due to the accumulation of charges near the surface, an internal electric field was formed. Electron-hole pairs that were created after the absorption of light are fallen in and then separated by the built-in electric field, which prevents radiative recombination process.

  2. Asymmetric spin-wave dispersion due to Dzyaloshinskii-Moriya interaction in an ultrathin Pt/CoFeB film

    SciTech Connect (OSTI)

    Di, Kai; Zhang, Vanessa Li; Lim, Hock Siah; Ng, Ser Choon; Kuok, Meng Hau; Qiu, Xuepeng; Yang, Hyunsoo

    2015-02-02

    Employing Brillouin spectroscopy, strong interfacial Dzyaloshinskii-Moriya interactions have been observed in an ultrathin Pt/CoFeB film. Our micromagnetic simulations show that spin-wave nonreciprocity due to asymmetric surface pinning is insignificant for the 0.8 nm-thick CoFeB film studied. The observed high asymmetry of the monotonic spin wave dispersion relation is thus ascribed to strong Dzyaloshinskii-Moriya interactions present at the Pt/CoFeB interface. Our findings should further enhance the significance of CoFeB as an important material for magnonic and spintronic applications.

  3. Document: 1095-0005 Actionee: Dorothy Riehie * Document Date: 10/21/2009 Due Date: NO ACTION

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

    v~il T op Document: 1095-0005 Actionee: Dorothy Riehie * Document Date: 10/21/2009 Due Date: NO ACTION i 1 4Author: EVENSON BG 9b Addressee: RIEHLE DC ATE S O' Title: FOIA Request for Print of May, 1943 Aerial Photographs L26-12 and L26-3 DIR DIV NAME DIR DIV NAME MGR AMRC DEP AMSE AMA EMD FMD OOD HRM SED PRO 0CC AMCP OCE Riehie, Dorothy (Actionee) AMMS ORP ISI PNSO PIC RLCI SES Comments: Original given to Dorothy Riehie. Records Schedule Information: ADM-1 .28.1 Scan?: Yes Sensitive?: No

  4. 07\pDcmn:N Actionee: Dorothy Riehie QDocument Date: 07/21/2009 Due Date: NO ACTION

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

    \pDcmn:N Actionee: Dorothy Riehie QDocument Date: 07/21/2009 Due Date: NO ACTION 4 Author: MORETZ 41 Addressee: RIEHLE DC TA2ES 01 Title: Sallee vs. Crown Cork & Seal Company, Inc., et al. DIR DIV NAME DIR DIV NAME MGR AMRC DEP AMSE AMA EMD FMD OOD HRM SED PRO 0CC AMCP OCE Riehie, Dorothy (Actionee) AMMS ORP ISI PNSO PIC RLCI SES Comments: ORIGINAL TO DC RIEHLE Records Schedule Information: Need to separate granted and denied requests. Scan?: Yes Sensitive?: Yes Sensitive Attachments IDMS

  5. Impacts of individual fish movement patterns on estimates of mortality due to dissolved gas supersaturation in the Columbia River Basin.

    SciTech Connect (OSTI)

    Scheibe, Timothy D.; Richmond, Marshall C.; Fidler, Larry E.

    2002-12-31

    Spatial and temporal distributions of dissolved gases in the Columbia and Snake rivers vary due to many factors including river channel and dam geometries, operational decisions, and natural variations in flow rates. As a result, the dissolved gas exposure histories experienced by migrating juvenile salmonids can vary significantly among individual fish. A discrete, particle-based model of individual fish movements and dissolved gas exposure history has been developed and applied to examine the effects of such variability on estimates of fish mortality. The model, called the Fish Individual-based Numerical Simulator or FINS, is linked to a two-dimensional (vertically-averaged) hydrodynamic simulator that quantifies local water velocity, temperature, and dissolved gas levels as a function of river flow rates and dam operations. Simulated gas exposure histories are then input to biological mortality models to predict the effects of various river configurations on fish injury and mortality due to dissolved gas supersaturation. This model framework provides a critical linkage between hydrodynamic models of the river system and models of biological effects. FINS model parameters were estimated and validated based on observations of individual fish movements collected using radiotelemetry methods during 1997 and 1998. The model was then used to simulate exposure histories under selected operational scenarios. We compare mortality rates estimated using the FINS model approach (incorporating individual behavior and spatial and temporal variability) to those estimated using average exposure times and levels as is done in traditional lumped-parameter model approaches.

  6. Structural changes of small amplitude kinetic Alfvén solitary waves due to second-order corrections

    SciTech Connect (OSTI)

    Choi, Cheong R.

    2015-10-15

    The structural changes of kinetic Alfvén solitary waves (KASWs) due to higher-order terms are investigated. While the first-order differential equation for KASWs provides the dispersion relation for kinetic Alfvén waves, the second-order differential equation describes the structural changes of the solitary waves due to higher-order nonlinearity. The reductive perturbation method is used to obtain the second-order and third-order partial differential equations; then, Kodama and Taniuti's technique [J. Phys. Soc. Jpn. 45, 298 (1978)] is applied in order to remove the secularities in the third-order differential equations and derive a linear second-order inhomogeneous differential equation. The solution to this new second-order equation indicates that, as the amplitude increases, the hump-type Korteweg-de Vries solution is concentrated more around the center position of the soliton and that dip-type structures form near the two edges of the soliton. This result has a close relationship with the interpretation of the complex KASW structures observed in space with satellites.

  7. Time-Dependent Reliability Analysis

    Energy Science and Technology Software Center (OSTI)

    1999-10-27

    FRANTIC-3 was developed to evaluate system unreliability using time-dependent techniques. The code provides two major options: to evaluate standby system unavailability or, in addition to the unavailability to calculate the total system failure probability by including both the unavailability of the system on demand as well as the probability that it will operate for an arbitrary time period following the demand. The FRANTIC-3 time dependent reliability models provide a large selection of repair and testingmore » policies applicable to standby or continously operating systems consisting of periodically tested, monitored, and non-repairable (non-testable) components. Time-dependent and test frequency dependent failures, as well as demand stress related failure, test-caused degradation and wear-out, test associated human errors, test deficiencies, test override, unscheduled and scheduled maintenance, component renewal and replacement policies, and test strategies can be prescribed. The conditional system unavailabilities associated with the downtimes of the user specified failed component are also evaluated. Optionally, the code can perform a sensitivity study for system unavailability or total failure probability to the failure characteristics of the standby components.« less

  8. Method and apparatus for simulating atmospheric absorption of solar energy due to water vapor and CO{sub 2}

    DOE Patents [OSTI]

    Sopori, B.L.

    1995-06-20

    A method and apparatus for improving the accuracy of the simulation of sunlight reaching the earth`s surface includes a relatively small heated chamber having an optical inlet and an optical outlet, the chamber having a cavity that can be filled with a heated stream of CO{sub 2} and water vapor. A simulated beam comprising infrared and near infrared light can be directed through the chamber cavity containing the CO{sub 2} and water vapor, whereby the spectral characteristics of the beam are altered so that the output beam from the chamber contains wavelength bands that accurately replicate atmospheric absorption of solar energy due to atmospheric CO{sub 2} and moisture. 8 figs.

  9. Method and apparatus for simulating atomospheric absorption of solar energy due to water vapor and CO.sub.2

    DOE Patents [OSTI]

    Sopori, Bhushan L.

    1995-01-01

    A method and apparatus for improving the accuracy of the simulation of sunlight reaching the earth's surface includes a relatively small heated chamber having an optical inlet and an optical outlet, the chamber having a cavity that can be filled with a heated stream of CO.sub.2 and water vapor. A simulated beam comprising infrared and near infrared light can be directed through the chamber cavity containing the CO.sub.2 and water vapor, whereby the spectral characteristics of the beam are altered so that the output beam from the chamber contains wavelength bands that accurately replicate atmospheric absorption of solar energy due to atmospheric CO.sub.2 and moisture.

  10. Momentum transport in the vicinity of q{sub min} in reverse shear tokamaks due to ion temperature gradient turbulence

    SciTech Connect (OSTI)

    Singh, Rameswar; Laboratoire de Physique des Plasmas, Ecole Polytechnique route de Saclay, 91128 Palaiseau Cedex ; Singh, R; WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon 305-333 ; Jhang, Hogun; Diamond, P. H.; Center for Momentum Transport and Flow Organization, University of California, San Diego, California 92093; Center for Astrophysics and Space Sciences, University of California San Diego, 9500 Gilman Dr., La Jolla, California 92093-0424

    2014-01-15

    We present an analytic study of momentum transport of tokamak plasmas in the vicinity of minimum safety factor (q) position in reversed magnetic shear configuration. Slab ion temperature gradient modes with an equilibrium flow profile are considered in this study. Quasi-linear calculations of momentum flux clearly show the novel effects of q-curvature on the generation of intrinsic rotation and mean poloidal flow without invoking reflectional symmetry breaking of parallel wavenumber (k{sub ?}). This q-curvature effect originates from the inherent asymmetry in k{sub ?} populations with respect to a rational surface due to the quadratic proportionality of k{sub ?} when q-curvature is taken into account. Discussions are made of possible implications of q-curvature induced plasma flows on internal transport barrier formation in reversed shear tokamaks.

  11. PROMPT X-RAY AND OPTICAL EXCESS EMISSION DUE TO HADRONIC CASCADES IN GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Asano, Katsuaki; Inoue, Susumu; Meszaros, Peter E-mail: inoue@tap.scphys.kyoto-u.ac.j

    2010-12-20

    A fraction of gamma-ray bursts (GRBs) exhibit distinct spectral features in their prompt emission below few tens of keV that exceed simple extrapolations of the low-energy power-law portion of the Band spectral model. This is also true for the prompt optical emission observed in several bursts. Through Monte Carlo simulations, we model such low-energy spectral excess components as hadronic cascade emission initiated by photomeson interactions of ultra-high-energy protons accelerated within GRB outflows. Synchrotron radiation from the cascading, secondary electron-positron pairs can naturally reproduce the observed soft spectra in the X-ray band, and in some cases the optical spectra as well. These components can be directly related to the higher energy radiation at GeV energies due to the hadronic cascades. Depending on the spectral shape, the total energy in protons is required to be comparable to or appreciably larger than the observed total photon energy. In particular, we apply our model to the excess X-ray and GeV emission of GRB 090902B, and the bright optical emission of the 'naked-eye' GRB 080319B. Besides the hard GeV components detected by Fermi, such X-ray or optical spectral excesses are further potential signatures of ultra-high-energy cosmic ray production in GRBs.

  12. Investigations into the seeding of instabilities due to x-ray preheat in beryllium-based inertial confinement fusion targets

    SciTech Connect (OSTI)

    Loomis, E. N.; Greenfield, S. R.; Johnson, R. P.; Cobble, J. A.; Luo, S. N.; Montgomery, D. S.; Marinak, M. M.

    2010-05-15

    The geometry of inertial confinement fusion (ICF) capsules makes them susceptible to various types of hydrodynamic instabilities at different stages during an ICF implosion. From the beginnings of ICF research, it has been known that grain-level anisotropy and defects could be a significant source of instability seeding in solid beryllium capsules. We report on experiments conducted at the Trident laser facility [S. H. Batha et al., Rev. Sci. Instrum. 79, 10F305 (2008)] to measure dynamic surface roughening from hard x-ray preheat due to anisotropic thermal expansion. M-band emission from laser-produced gold plasma was used to heat beryllium targets with different amounts of copper doping to temperatures comparable to ICF ignition preheat levels. Dynamic roughening measurements were made on the surface away from the plasma at discrete times up to 8 ns after the beginning of the drive pulse using a surface displacement interferometer with nanometer scale sensitivity. Undoped large-grained targets were measured to roughen between 15 and 50 nm rms. Fine-grained, copper-doped targets were observed to roughen near the sensitivity limit of the interferometer. The results of this work have shed light on the effects of high-Z doping and microstructural refinement on the dynamics of differential thermal expansion and have shown that current ICF capsule designs using beryllium are very effective in reducing preheat related roughening ahead of the first shock.

  13. Study of public school tax revenue losses due to current tax appraisals of selected West Virginia coal lands

    SciTech Connect (OSTI)

    Froehlich, L.G.

    1984-01-01

    The purpose of this study was 1) to compare the West Virginia State Tax Department's method of appraising coal property to the requirements of the West Virginia State Code; 2) to develop an alternative appraisal formula for West Virginia coal property, and 3) to compare the property tax revenue of identified West Virginia counties using the current appraisal formula and the formula developed through the study. A modified coal property appraisal formula was developed. The modified formula was sent to coal producing states, professional appraisers, and engineers for comments. The study then took coal property data from 12 West Virginia counties and applied the current and the modified formulas. The result of the modification applied to 12 of the 34 coal producing counties produced an additional 6.6 million dollars in tax revenue. The major conclusion was that a vast amount of tax revenue is available from property taxes but is not being collected due to the inaccurate property appraisals by the State Tax Department. Large sums of property tax revenue should be available without creating new tax laws or raising levy rates, but by following the West Virginia Code.

  14. Laser-to-hot-electron conversion limitations in relativistic laser matter interactions due to multi-picosecond dynamics

    SciTech Connect (OSTI)

    Schollmeier, Marius; Sefkow, Adam B.; Geissel, Matthias; Arefiev, Alexey V.; Flippo, Kirk A.; Gaillard, Sandrine A.; Johnson, Randy P.; Kimmel, Mark W.; Offermann, Dustin T.; Rambo, Patrick K.; Schwarz, Jens; Shimada, Tom

    2015-04-20

    High-energy short-pulse lasers are pushing the limits of plasma-based particle acceleration, x-ray generation, and high-harmonic generation by creating strong electromagnetic fields at the laser focus where electrons are being accelerated to relativistic velocities. Understanding the relativistic electron dynamics is key for an accurate interpretation of measurements. We present a unified and self-consistent modeling approach in quantitative agreement with measurements and differing trends across multiple target types acquired from two separate laser systems, which differ only in their nanosecond to picosecond-scale rising edge. Insights from high-fidelity modeling of laser-plasma interaction demonstrate that the ps-scale, orders of magnitude weaker rising edge of the main pulse measurably alters target evolution and relativistic electron generation compared to idealized pulse shapes. This can lead for instance to the experimentally observed difference between 45 MeV and 75 MeV maximum energy protons for two nominally identical laser shots, due to ps-scale prepulse variations. Our results indicate that the realistic inclusion of temporal laser pulse profiles in modeling efforts is required if predictive capability and extrapolation are sought for future target and laser designs or for other relativistic laser ion acceleration schemes.

  15. Laser-to-hot-electron conversion limitations in relativistic laser matter interactions due to multi-picosecond dynamics

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

    Schollmeier, Marius; Sefkow, Adam B.; Geissel, Matthias; Arefiev, Alexey V.; Flippo, Kirk A.; Gaillard, Sandrine A.; Johnson, Randy P.; Kimmel, Mark W.; Offermann, Dustin T.; Rambo, Patrick K.; et al

    2015-04-20

    High-energy short-pulse lasers are pushing the limits of plasma-based particle acceleration, x-ray generation, and high-harmonic generation by creating strong electromagnetic fields at the laser focus where electrons are being accelerated to relativistic velocities. Understanding the relativistic electron dynamics is key for an accurate interpretation of measurements. We present a unified and self-consistent modeling approach in quantitative agreement with measurements and differing trends across multiple target types acquired from two separate laser systems, which differ only in their nanosecond to picosecond-scale rising edge. Insights from high-fidelity modeling of laser-plasma interaction demonstrate that the ps-scale, orders of magnitude weaker rising edge ofmore » the main pulse measurably alters target evolution and relativistic electron generation compared to idealized pulse shapes. This can lead for instance to the experimentally observed difference between 45 MeV and 75 MeV maximum energy protons for two nominally identical laser shots, due to ps-scale prepulse variations. Our results indicate that the realistic inclusion of temporal laser pulse profiles in modeling efforts is required if predictive capability and extrapolation are sought for future target and laser designs or for other relativistic laser ion acceleration schemes.« less

  16. Laser-to-hot-electron conversion limitations in relativistic laser matter interactions due to multi-picosecond dynamics

    SciTech Connect (OSTI)

    Schollmeier, M.; Sefkow, A. B.; Geissel, M.; Kimmel, M. W.; Rambo, P. K.; Schwarz, J.; Arefiev, A. V.; Flippo, K. A.; Johnson, R. P.; Shimada, T.; Gaillard, S. A.; Offermann, D. T.

    2015-04-15

    High-energy short-pulse lasers are pushing the limits of plasma-based particle acceleration, x-ray generation, and high-harmonic generation by creating strong electromagnetic fields at the laser focus where electrons are being accelerated to relativistic velocities. Understanding the relativistic electron dynamics is key for an accurate interpretation of measurements. We present a unified and self-consistent modeling approach in quantitative agreement with measurements and differing trends across multiple target types acquired from two separate laser systems, which differ only in their nanosecond to picosecond-scale rising edge. Insights from high-fidelity modeling of laser-plasma interaction demonstrate that the ps-scale, orders of magnitude weaker rising edge of the main pulse measurably alters target evolution and relativistic electron generation compared to idealized pulse shapes. This can lead for instance to the experimentally observed difference between 45 MeV and 75 MeV maximum energy protons for two nominally identical laser shots, due to ps-scale prepulse variations. Our results show that the realistic inclusion of temporal laser pulse profiles in modeling efforts is required if predictive capability and extrapolation are sought for future target and laser designs or for other relativistic laser ion acceleration schemes.

  17. LARGE PECULIAR MOTION OF THE SOLAR SYSTEM FROM THE DIPOLE ANISOTROPY IN SKY BRIGHTNESS DUE TO DISTANT RADIO SOURCES

    SciTech Connect (OSTI)

    Singal, Ashok K.

    2011-12-15

    According to the cosmological principle, the universe should appear isotropic, without any preferred directions, to an observer whom we may consider to be fixed in the comoving coordinate system of the expanding universe. Such an observer is stationary with respect to the average distribution of the matter in the universe and the sky brightness at any frequency should appear uniform in all directions to such an observer. However, a peculiar motion of such an observer, due to a combined effect of Doppler boosting and aberration, will introduce a dipole anisotropy in the observed sky brightness; in reverse an observed dipole anisotropy in the sky brightness could be used to infer the peculiar velocity of the observer with respect to the average universe. We determine the peculiar velocity of the solar system relative to the frame of distant radio sources, by studying the anisotropy in the sky brightness from discrete radio sources, i.e., an integrated emission from discrete sources per unit solid angle. Our results give a direction of the velocity vector in agreement with the cosmic microwave background radiation (CMBR) value, but the magnitude ({approx}1600 {+-} 400 km s{sup -1}) is {approx}4 times the CMBR value (369 {+-} 1 km s{sup -1}) at a statistically significant ({approx}3{sigma}) level. A genuine difference between the two dipoles would imply an anisotropic universe, with the anisotropy changing with the epoch. This would violate the cosmological principle where the isotropy of the universe is assumed for all epochs, and on which the whole modern cosmology is based upon.

  18. MODELING THE ANOMALY OF SURFACE NUMBER DENSITIES OF GALAXIES ON THE GALACTIC EXTINCTION MAP DUE TO THEIR FIR EMISSION CONTAMINATION

    SciTech Connect (OSTI)

    Kashiwagi, Toshiya; Suto, Yasushi; Taruya, Atsushi; Yahata, Kazuhiro; Kayo, Issha; Nishimichi, Takahiro

    2015-02-01

    The most widely used Galactic extinction map is constructed assuming that the observed far-infrared (FIR) fluxes come entirely from Galactic dust. According to the earlier suggestion by Yahata et al., we consider how FIR emission of galaxies affects the SFD map. We first compute the surface number density of Sloan Digital Sky Survey (SDSS) DR7 galaxies as a function of the r-band extinction, A {sub r,} {sub SFD}. We confirm that the surface densities of those galaxies positively correlate with A {sub r,} {sub SFD} for A {sub r,} {sub SFD} < 0.1, as first discovered by Yahata et al. for SDSS DR4 galaxies. Next we construct an analytical model to compute the surface density of galaxies, taking into account the contamination of their FIR emission. We adopt a log-normal probability distribution for the ratio of 100 ?m and r-band luminosities of each galaxy, y ? (?L){sub 100} {sub ?m}/(?L) {sub r}. Then we search for the mean and rms values of y that fit the observed anomaly, using the analytical model. The required values to reproduce the anomaly are roughly consistent with those measured from the stacking analysis of SDSS galaxies. Due to the limitation of our statistical modeling, we are not yet able to remove the FIR contamination of galaxies from the extinction map. Nevertheless, the agreement with the model prediction suggests that the FIR emission of galaxies is mainly responsible for the observed anomaly. Whereas the corresponding systematic error in the Galactic extinction map is 0.1-1mmag, it is directly correlated with galaxy clustering and thus needs to be carefully examined in precision cosmology.

  19. TESTING AND ANALYSIS OF CAP CONCRETE STRESS AND STRAIN DUE TO SHRINKAGE, CREEP, AND EXPANSION FINAL REPORT

    SciTech Connect (OSTI)

    Guerrero, H.; Restivo, M.

    2011-08-01

    In-situ decommissioning of Reactors P- and R- at the Savannah River Site will require filling the reactor vessels with a special concrete based on materials such as magnesium phosphate, calcium aluminate or silica fume. Then the reactor vessels will be overlain with an 8 ft. thick layer of Ordinary Portland Cement (OPC) steel reinforced concrete, called the 'Cap Concrete'. The integrity of this protective layer must be assured to last for a sufficiently long period of time to avoid ingress of water into the reactor vessel and possible movement of radioactive contamination into the environment. During drying of this Cap Concrete however, shrinkage strains are set up in the concrete as a result of diffusion and evaporation of water from the top surface. This shrinkage varies with depth in the poured slab due to a non-uniform moisture distribution. This differential shrinkage results in restraint of the upper layers with larger shrinkage by lower layers with lesser displacements. Tensile stresses can develop at the surface from the strain gradients in the bulk slab, which can lead to surface cracking. Further, a mechanism called creep occurs during the curing period or early age produces strains under the action of restraining forces. To investigate the potential for surface cracking, an experimental and analytical program was started under TTQAP SRNL-RP-2009-01184. Slab sections made of Cap Concrete mixture were instrumented with embedded strain gages and relative humidity sensors and tested under controlled environmental conditions of 23 C and relative humidities (RH) of 40% and 80% over a period of 50 days. Calculation methods were also developed for predictions of stress development in the full-scale concrete placement over the reactor vessels. These methods were evaluated by simulating conditions for the test specimens and the calculation results compared to the experimental data. A closely similar test with strain gages was performed by Kim and Lee for a

  20. Consistent quantification of climate impacts due to biogenic carbon storage across a range of bio-product systems

    SciTech Connect (OSTI)

    Guest, Geoffrey Bright, Ryan M. Cherubini, Francesco Strmman, Anders H.

    2013-11-15

    Temporary and permanent carbon storage from biogenic sources is seen as a way to mitigate climate change. The aim of this work is to illustrate the need to harmonize the quantification of such mitigation across all possible storage pools in the bio- and anthroposphere. We investigate nine alternative storage cases and a wide array of bio-resource pools: from annual crops, short rotation woody crops, medium rotation temperate forests, and long rotation boreal forests. For each feedstock type and biogenic carbon storage pool, we quantify the carbon cycle climate impact due to the skewed time distribution between emission and sequestration fluxes in the bio- and anthroposphere. Additional consideration of the climate impact from albedo changes in forests is also illustrated for the boreal forest case. When characterizing climate impact with global warming potentials (GWP), we find a large variance in results which is attributed to different combinations of biomass storage and feedstock systems. The storage of biogenic carbon in any storage pool does not always confer climate benefits: even when biogenic carbon is stored long-term in durable product pools, the climate outcome may still be undesirable when the carbon is sourced from slow-growing biomass feedstock. For example, when biogenic carbon from Norway Spruce from Norway is stored in furniture with a mean life time of 43 years, a climate change impact of 0.08 kg CO{sub 2}eq per kg CO{sub 2} stored (100 year time horizon (TH)) would result. It was also found that when biogenic carbon is stored in a pool with negligible leakage to the atmosphere, the resulting GWP factor is not necessarily ? 1 CO{sub 2}eq per kg CO{sub 2} stored. As an example, when biogenic CO{sub 2} from Norway Spruce biomass is stored in geological reservoirs with no leakage, we estimate a GWP of ? 0.56 kg CO{sub 2}eq per kg CO{sub 2} stored (100 year TH) when albedo effects are also included. The large variance in GWPs across the range of

  1. A charged particle transport analysis of the dose to a silicon-germanium thermoelectric element due to a solar flare event

    SciTech Connect (OSTI)

    Dandini, V.J.

    1991-01-01

    A version of the BRYNTRN baryon transport code written at the NASA Langley Research Center has been used to analyze the dose to a typical space reactor thermoelectric (TE) element due to a solar flare event. The code has been used in the past to calculate the dose/dose equivalent distributions to astronauts due to solar flares. It has been modified to accommodate multiple layers of spacecraft and component material. Differential and integrated doses to the TE element are presented and discussed. 5 refs.

  2. Verification of maximum radial power peaking factor due to insertion of FPM-LEU target in the core of RSG-GAS reactor

    SciTech Connect (OSTI)

    Setyawan, Daddy; Rohman, Budi

    2014-09-30

    Verification of Maximum Radial Power Peaking Factor due to insertion of FPM-LEU target in the core of RSG-GAS Reactor. Radial Power Peaking Factor in RSG-GAS Reactor is a very important parameter for the safety of RSG-GAS reactor during operation. Data of radial power peaking factor due to the insertion of Fission Product Molybdenum with Low Enriched Uranium (FPM-LEU) was reported by PRSG to BAPETEN through the Safety Analysis Report RSG-GAS for FPM-LEU target irradiation. In order to support the evaluation of the Safety Analysis Report incorporated in the submission, the assessment unit of BAPETEN is carrying out independent assessment in order to verify safety related parameters in the SAR including neutronic aspect. The work includes verification to the maximum radial power peaking factor change due to the insertion of FPM-LEU target in RSG-GAS Reactor by computational method using MCNP5and ORIGEN2. From the results of calculations, the new maximum value of the radial power peaking factor due to the insertion of FPM-LEU target is 1.27. The results of calculations in this study showed a smaller value than 1.4 the limit allowed in the SAR.

  3. SSRL BEAM PORT SCHEDULE

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

    18, 2006 Feb. 19, 2006 1B25 J.MARTINEZ 6A96 D.WILSON 9B01 A.DEACON Unscheduled 8044 I.MATHEWS 1B43 C.STOUT 1B43 C.STOUT MC CHECKOUT6A96 CHANGE9B01 A.DEAC Unscheduled Unscheduled...

  4. Measurement of cross-field power loss due to rovibrationally excited H{sub 2} in a detached hydrogen divertor plasma simulator

    SciTech Connect (OSTI)

    Hollmann, E.M.; Pigarov, A.Yu.; Yan, Z.

    2006-05-15

    The cross-field power loss due to radiation, plasma, and neutrals are measured for hydrogen discharges in a linear divertor simulator experiment. Radiation appears to be the dominant power loss channel; however, power loss due to heating of H{sub 2} neutrals is found to be quite significant, being only 2x weaker than radiation in the higher neutral pressure experiments. The H{sub 2} vibrational temperature T{sub vib} is found to be the most important channel for carrying neutral energy out of the plasma--more important than either kinetic temperature T{sub kin} or rotational temperature T{sub rot}. Power carried radially to the wall by plasma cross-field transport is found to be negligible when compared to neutral and radiation losses. These results demonstrate the importance of including of H{sub 2} neutrals in understanding power balance in detached tokamak divertors.

  5. Two-dimensional nonlinear finite element analysis of well damage due to reservoir compaction, well-to-well interactions, and localization on weak layers

    SciTech Connect (OSTI)

    Hilbert, L.B. Jr.; Fredrich, J.T.; Bruno, M.S.; Deitrick, G.L.; Rouffignac, E.P. de

    1996-05-01

    In this paper the authors present the results of a coupled nonlinear finite element geomechanics model for reservoir compaction and well-to-well interactions for the high-porosity, low strength diatomite reservoirs of the Belridge field near Bakersfield, California. They show that well damage and failures can occur under the action of two distinct mechanisms: shear deformations induced by pore compaction, and subsidence, and shear deformations due to well-to-well interactions during production or water injection. They show such casting damage or failure can be localized to weak layers that slide or slip under shear due to subsidence. The magnitude of shear displacements and surface subsidence agree with field observations.

  6. SU-E-T-645: Dose Enhancement to Cell Nucleus Due to Hard Collisions of Protons with Electrons in Gold Nanospheres

    SciTech Connect (OSTI)

    Eley, J; Krishnan, S

    2014-06-15

    Purpose: The purpose of this study was to investigate the theoretical dose enhancement to a cell nucleus due to increased fluence of secondary electrons when gold nanospheres are present in the cytoplasm during proton therapy. Methods: We modeled the irradiation of prostate cancer cells using protons of variable energies when 10,000 gold nanoparticles, each with radius of 10 nm, were randomly distributed in the cytoplasm. Using simple analytical equations, we calculated the increased mean dose to the cell nucleus due to secondary electrons produced by hard collisions of 0.1, 1, 10, and 100 MeV protons with orbital electrons in gold. We only counted electrons with kinetic energy higher than 1 keV. In addition to calculating the increase in the mean dose to the cell nucleus, we also calculated the increase in local dose in the “shadow,” i.e., the umbra, of individual gold nanospheres due to forward scattered electrons. Results: For proton energies of 0.1, 1, 10, and 100 MeV, we calculated increases to the mean nuclear dose of 0.15, 0.09, 0.05, and 0.04%, respectively. When we considered local dose increases in the shadows of individual gold spheres, we calculated local dose increases of 5.5, 3.2, 1.9, and 1.3%, respectively. Conclusion: We found negligible, less than 0.2%, increases in the mean dose to the cell nucleus due to electrons produced by hard collisions of protons with electrons in gold nanospheres. However, we observed increases up to 5.5% in the local dose in the shadow of gold nanospheres. Considering the shadow radius of 10 nm, these local dose enhancements may have implications for slightly increased probability of clustered DNA damage when gold nanoparticles are close to the nuclear membrane.

  7. Case report of a near medical event in stereotactic radiotherapy due to improper units of measure from a treatment planning system

    SciTech Connect (OSTI)

    Gladstone, D. J.; Li, S.; Jarvis, L. A.; Hartford, A. C.

    2011-07-15

    Purpose: The authors hereby notify the Radiation Oncology community of a potentially lethal error due to improper implementation of linear units of measure in a treatment planning system. The authors report an incident in which a patient was nearly mistreated during a stereotactic radiotherapy procedure due to inappropriate reporting of stereotactic coordinates by the radiation therapy treatment planning system in units of centimeter rather than in millimeter. The authors suggest a method to detect such errors during treatment planning so they are caught and corrected prior to the patient positioning for treatment on the treatment machine. Methods: Using pretreatment imaging, the authors found that stereotactic coordinates are reported with improper linear units by a treatment planning system. The authors have implemented a redundant, independent method of stereotactic coordinate calculation. Results: Implementation of a double check of stereotactic coordinates via redundant, independent calculation is simple and accurate. Use of this technique will avoid any future error in stereotactic treatment coordinates due to improper linear units, transcription, or other similar errors. Conclusions: The authors recommend an independent double check of stereotactic treatment coordinates during the treatment planning process in order to avoid potential mistreatment of patients.

  8. Instability due to a two recirculation pump trip in a BWR using RAMONA-4B computer code with 3D neutron kinetics

    SciTech Connect (OSTI)

    Cheng, H.S.; Rohatgi, U.S.

    1993-06-01

    An investigation was made of the potential for thermal-hydraulic instabilities coupled to neutronic feedback in a BWR due to a two recirculation pump trip event using the RAMONA-4B computer code with 3D neutron kinetics. It is concluded that a high-power (100%) and low-flow (75%) initial condition would most likely lead to in-phase density wave oscillations after the tripping of both recirculation pumps, and that RAMONA-4B is capable of predicting such thermal-hydraulic instabilities coupled to neutronic feedback in BWR and in SBWR.

  9. Economic assessment of the impact on coal production due to enforcement of the Surface Mining Control and Reclamation Act of 1977. Cost report. Final report

    SciTech Connect (OSTI)

    Not Available

    1980-11-12

    The report summarizes the efforts made in the cost analysis portion of the 'Economic Assessment of the Impact on Coal Production Due to Enforcement of the Surface Mining Control and Reclamation Act (SMCRA) of 1977. The objective of the cost analysis portion of the study was to supplement the study's examination of the benefits of SMCRA with an analysis of the costs of SMCRA as based on industry experience and data. The analysis involved the development and field test of a methodology for constructing estimates of the costs of complying with regulations at individual surface coal mines.

  10. Electrical current suppression in Pd-doped vanadium pentoxide nanowires caused by reduction in PdO due to hydrogen exposure

    SciTech Connect (OSTI)

    Kim, Byung Hoon; Oh, Soon-Young; Yu, Han Young; Yun, Yong Ju; Kim, Yark Yeon; Hong, Won G.; Jeong, Hu Young; Lee, Jeong Yong; Kim, Hae Jin

    2010-04-19

    Pd nanoparticle-doped vanadium pentoxide nanowires (Pd-VONs) were synthesized. Electrical current suppression was observed when the Pd-VON was exposed to hydrogen gas, which cannot be explained by the work function changes mentioned in previous report such as Pd-doped carbon nanotubes and SnO{sub 2} nanowires. Using the x-ray photoelectron spectroscopy, we found that the reduction in PdO due to hydrogen exposure plays an important role in the current suppression of the Pd-VON.

  11. Methods For Calculating Thyroid Doses to The Residents Of Ozersk Due to 131I Releases From The Stacks of The Mayak Production Association

    SciTech Connect (OSTI)

    Rovny, Sergey I.; Mokrov, Y.; Stukalov, Pavel M.; Beregich, D. A.; Teplyakov, I. I.; Anspaugh, L. R.; Napier, Bruce A.

    2009-10-23

    The Mayak Production Association (MPA) was established in the late 1940s in accordance with a special Decree of the USSR Government for the production of nuclear weapons. In early years of MPA operation, due to the lack of experience and absence of effective methods of RW management, the enterprise had extensive routine (designed) and non-routine (accidental) releases of gaseous radioactive wastes to the atmosphere. These practices resulted in additional technogenic radiation exposure of residents inhabiting populated areas near the MPA. The primary objective of ongoing studies under JCCRER Project 1.4 is to estimate doses to the residents of Ozersk due to releases of radioactive substances from the stacks of MPA. Preliminary scoping studies have demonstrated that releases of radioactive iodine (131I) from the stacks of the Mayak Radiochemical Plant represented the major contribution to the dose to residents of Ozersk and of other nearby populated areas. The behavior of 131I in the environment and of 131I migration through biological food chains (vegetation-cows-milk-humans) indicated a need for use of special mathematical models to perform the estimation of radiation doses to the population. The goal of this work is to select an appropriate model of the iodine migration in biological food chains and to justify numerical values of the model parameters.

  12. Domain formation due to surface steps in topological insulator Bi{sub 2}Te{sub 3} thin films grown on Si (111) by molecular beam epitaxy

    SciTech Connect (OSTI)

    Borisova, S.; Kampmeier, J.; Mussler, G.; Grützmacher, D.; Jülich Aachen Research Alliance, Fundamentals of Future Information Technologies, Jülich 52425 ; Luysberg, M.

    2013-08-19

    The atomic structure of topological insulators Bi{sub 2}Te{sub 3} thin films on Si (111) substrates grown in van der Waals mode by molecular beam epitaxy has been investigated by in situ scanning tunneling microscopy and scanning transmission electron microscopy. Besides single and multiple quintuple layer (QL) steps, which are typical for the step-flow mode of growth, a number of 0.4 QL steps is observed. We determine that these steps originate from single steps at the substrate surface causing domain boundaries in the Bi{sub 2}Te{sub 3} film. Due to the peculiar structure of these domain boundaries the domains are stable and penetrate throughout the entire film.

  13. Hypoxia induced E-cadherin involving regulators of Hippo pathway due to HIF-1α stabilization/nuclear translocation in bone metastasis from breast carcinoma

    SciTech Connect (OSTI)

    Maroni, Paola; Matteucci, Emanuela; Drago, Lorenzo; Banfi, Giuseppe; Bendinelli, Paola; Desiderio, Maria Alfonsina

    2015-01-15

    The present study deals with the molecular mechanisms involved in the regulation of E-cadherin expression under hypoxia, because the adjustment of the amount of E-cadherin due to physical stimuli of the microenvironment might influence the colonization of metastasis to skeleton. We analyzed the effect of 1% oxygen tension, that is similar to that encountered in the bone marrow by metastatic cells spreading from breast carcinoma. The purpose was to evaluate the hypoxia-orchestrated control of E-cadherin transactivation via hypoxia inducible factor-1 (HIF-1) and peroxisome proliferator activated receptor-γ (PPARγ), and the involvement of Hippo pathway members, as regulators of transcription factors. To give a translational significance to the study, we took into consideration human pair-matched ductal breast carcinoma and bone metastasis: E-cadherin and Wwox were expressed in bone metastasis but not in breast carcinoma, while HIF-1α and TAZ seemed localized principally in nuclei of metastasis and were found in all cell compartments of breast carcinoma. A close examination of the regulatory mechanisms underlying E-cadherin expression in bone metastasis was done in 1833 clone derived from MDA-MB231 cells. Hypoxia induced E-cadherin only in 1833 clone, but not in parental cells, through HIF-1 and PPARγ activities, while Wwox decreased. Since Wwox was highly expressed in bone metastasis, the effect of ectopic Wwox was evaluated, and we showed E-cadherin transactivation and enhanced invasiveness in WWOX transfected 1833 cells. Also, hypoxia was additive with ectopic Wwox remarkably enhancing HIF-1α nuclear shuttle and accumulation due to the lengthening of the half-life of HIF-1α protein; under this experimental condition HIF-1α appeared as a slower migrated band compared with control, in agreement with the phosphorylation state. The in vitro data strongly supported the almost exclusive presence of HIF-1α in nuclei of human-bone metastasis. Thus, we identified

  14. Evaluation of Radiation Doses Due to Consumption of Contaminated Food Items and Calculation of Food Class-Specific Derived Intervention Levels

    SciTech Connect (OSTI)

    Heinzelman, K M; Mansfield, W G

    2010-04-27

    This document evaluates the expected radiation dose due to the consumption of several specific food classes (dairy, meat, produce, etc.) contaminated with specific radionuclides, and relates concentration levels in food to the detection abilities of typical aboratory analysis/measurement methods. The attached charts present the limiting organ dose as a function of the radionuclide concentration in a particular food class, and allow the user to compare these concentrations and doses to typical analytical detection apabilities. The expected radiation dose depends on several factors: the age of the individual; the radionuclide present in the food; the concentration of the radionuclide in the food; and the amount of food consumed. Food consumption rates for individuals of various ges were taken from the 1998 United States Food and Drug Administration (FDA) document, Accidental Radioactive Contamination of HUman Food and Animal Feeds: Recommendations for State and Local Agencies. In that document, the FDA defines the erived Intervention Level (DIL), which is the concentration of a particular radionuclide in food that if consumed could result in an individual receiving a radiation dose exceeding the Protection Action Guide (PAG) thresholds for intervention. This document also resents odified, food class specific DIL, which is calculated using a somewhat modified version of the FDA's procedure. This document begins with an overview of the FDA's DIL calculation, followed by a description of the food class specific DIL calculations, and finally charts of the radiation dose per radioactivity concentration for several food class/radionuclide combinations.

  15. Preliminary Assessment of the Impact on Reactor Vessel dpa Rates Due to Installation of a Proposed Low Enriched Uranium (LEU) Core in the High Flux Isotope Reactor (HFIR)

    SciTech Connect (OSTI)

    Daily, Charles R.

    2015-10-01

    An assessment of the impact on the High Flux Isotope Reactor (HFIR) reactor vessel (RV) displacements-per-atom (dpa) rates due to operations with the proposed low enriched uranium (LEU) core described by Ilas and Primm has been performed and is presented herein. The analyses documented herein support the conclusion that conversion of HFIR to low-enriched uranium (LEU) core operations using the LEU core design of Ilas and Primm will have no negative impact on HFIR RV dpa rates. Since its inception, HFIR has been operated with highly enriched uranium (HEU) cores. As part of an effort sponsored by the National Nuclear Security Administration (NNSA), conversion to LEU cores is being considered for future HFIR operations. The HFIR LEU configurations analyzed are consistent with the LEU core models used by Ilas and Primm and the HEU balance-of-plant models used by Risner and Blakeman in the latest analyses performed to support the HFIR materials surveillance program. The Risner and Blakeman analyses, as well as the studies documented herein, are the first to apply the hybrid transport methods available in the Automated Variance reduction Generator (ADVANTG) code to HFIR RV dpa rate calculations. These calculations have been performed on the Oak Ridge National Laboratory (ORNL) Institutional Cluster (OIC) with version 1.60 of the Monte Carlo N-Particle 5 (MCNP5) computer code.

  16. Dotiki saves money and time with power tool and belt fasteners

    SciTech Connect (OSTI)

    Bargo, K.

    2009-11-15

    The use of a Hilti power tool to improve belt splice installations to minimise downtime is described. 3 photos.

  17. SU-E-T-235: Monte Carlo Analysis of the Dose Enhancement in the Scalp of Patients Due to Titanium Plate Backscatter During Post-Operative Radiotherapy

    SciTech Connect (OSTI)

    Hardin, M; Elson, H; Lamba, M; Wolf, E; Warnick, R

    2014-06-01

    Purpose: To quantify the clinically observed dose enhancement adjacent to cranial titanium fixation plates during post-operative radiotherapy. Methods: Irradiation of a titanium burr hole cover was simulated using Monte Carlo code MCNPX for a 6 MV photon spectrum to investigate backscatter dose enhancement due to increased production of secondary electrons within the titanium plate. The simulated plate was placed 3 mm deep in a water phantom, and dose deposition was tallied for 0.2 mm thick cells adjacent to the entrance and exit sides of the plate. These results were compared to a simulation excluding the presence of the titanium to calculate relative dose enhancement on the entrance and exit sides of the plate. To verify simulated results, two titanium burr hole covers (Synthes, Inc. and Biomet, Inc.) were irradiated with 6 MV photons in a solid water phantom containing GafChromic MD-55 film. The phantom was irradiated on a Varian 21EX linear accelerator at multiple gantry angles (0–180 degrees) to analyze the angular dependence of the backscattered radiation. Relative dose enhancement was quantified using computer software. Results: Monte Carlo simulations indicate a relative difference of 26.4% and 7.1% on the entrance and exit sides of the plate respectively. Film dosimetry results using a similar geometry indicate a relative difference of 13% and -10% on the entrance and exit sides of the plate respectively. Relative dose enhancement on the entrance side of the plate decreased with increasing gantry angle from 0 to 180 degrees. Conclusion: Film and simulation results demonstrate an increase in dose to structures immediately adjacent to cranial titanium fixation plates. Increased beam obliquity has shown to alleviate dose enhancement to some extent. These results are consistent with clinically observed effects.

  18. Fetal and neonatal exposure to nicotine leads to augmented hepatic and circulating triglycerides in adult male offspring due to increased expression of fatty acid synthase

    SciTech Connect (OSTI)

    Ma, Noelle; Nicholson, Catherine J.; Wong, Michael; Holloway, Alison C.; Hardy, Daniel B.

    2014-02-15

    While nicotine replacement therapy is assumed to be a safer alternative to smoking during pregnancy, the long-term consequences for the offspring remain elusive. Animal studies now suggest that maternal nicotine exposure during perinatal life leads to a wide range of adverse outcomes for the offspring including increased adiposity. The focus of this study was to investigate if nicotine exposure during pregnancy and lactation leads to alterations in hepatic triglyceride synthesis. Female Wistar rats were randomly assigned to receive daily subcutaneous injections of saline (vehicle) or nicotine bitartrate (1 mg/kg/day) for two weeks prior to mating until weaning. At postnatal day 180 (PND 180), nicotine exposed offspring exhibited significantly elevated levels of circulating and hepatic triglycerides in the male offspring. This was concomitant with increased expression of fatty acid synthase (FAS), the critical hepatic enzyme in de novo triglyceride synthesis. Given that FAS is regulated by the nuclear receptor Liver X receptor (LXR?), we measured LXR? expression in both control and nicotine-exposed offspring. Nicotine exposure during pregnancy and lactation led to an increase in hepatic LXR? protein expression and enriched binding to the putative LXRE element on the FAS promoter in PND 180 male offspring. This was also associated with significantly enhanced acetylation of histone H3 [K9,14] surrounding the FAS promoter, a hallmark of chromatin activation. Collectively, these findings suggest that nicotine exposure during pregnancy and lactation leads to an increase in circulating and hepatic triglycerides long-term via changes in the transcriptional and epigenetic regulation of the hepatic lipogenic pathway. - Highlights: Our data reveals the links nicotine exposure in utero and long-term hypertriglyceridemia. It is due to nicotine-induced augmented expression of hepatic FAS and LXR? activity. Moreover, this involves nicotine-induced enhanced acetylation of

  19. Alisol B 23-acetate protects against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes involved in bile acid homeostasis

    SciTech Connect (OSTI)

    Meng, Qiang; Chen, Xin-li; Wang, Chang-yuan; Liu, Qi; Sun, Hui-jun; Sun, Peng-yuan; Huo, Xiao-kui; Liu, Zhi-hao; Yao, Ji-hong; Liu, Ke-xin

    2015-03-15

    Intrahepatic cholestasis is a clinical syndrome with systemic and intrahepatic accumulation of excessive toxic bile acids that ultimately cause hepatobiliary injury. Appropriate regulation of bile acids in hepatocytes is critically important for protection against liver injury. In the present study, we characterized the protective effect of alisol B 23-acetate (AB23A), a natural triterpenoid, on alpha-naphthylisothiocyanate (ANIT)-induced liver injury and intrahepatic cholestasis in mice and further elucidated the mechanisms in vivo and in vitro. AB23A treatment dose-dependently protected against liver injury induced by ANIT through reducing hepatic uptake and increasing efflux of bile acid via down-regulation of hepatic uptake transporters (Ntcp) and up-regulation of efflux transporter (Bsep, Mrp2 and Mdr2) expression. Furthermore, AB23A reduced bile acid synthesis through repressing Cyp7a1 and Cyp8b1, increased bile acid conjugation through inducing Bal, Baat and bile acid metabolism through an induction in gene expression of Sult2a1. We further demonstrate the involvement of farnesoid X receptor (FXR) in the hepatoprotective effect of AB23A. The changes in transporters and enzymes, as well as ameliorative liver histology in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly demonstrated the effect of AB23A on FXR activation in a dose-dependent manner using luciferase reporter assay in HepG2 cells. In conclusion, AB23A produces protective effect against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes. - Highlights: • AB23A has at least three roles in protection against ANIT-induced liver injury. • AB23A decreases Ntcp, and increases Bsep, Mrp2 and Mdr2 expression. • AB23A represses Cyp7a1 and Cyp8b1 through inducing Shp and Fgf15 expression. • AB23A increases bile acid metabolism through inducing Sult2a1 expression. • FXR activation is involved

  20. A cascaded model of spectral distortions due to spectral response effects and pulse pileup effects in a photon-counting x-ray detector for CT

    SciTech Connect (OSTI)

    Cammin, Jochen E-mail: ktaguchi@jhmi.edu; Taguchi, Katsuyuki E-mail: ktaguchi@jhmi.edu; Xu, Jennifer; Barber, William C.; Iwanczyk, Jan S.; Hartsough, Neal E.

    2014-04-15

    Purpose: Energy discriminating, photon-counting detectors (PCDs) are an emerging technology for computed tomography (CT) with various potential benefits for clinical CT. The photon energies measured by PCDs can be distorted due to the interactions of a photon with the detector and the interaction of multiple coincident photons. These effects result in distorted recorded x-ray spectra which may lead to artifacts in reconstructed CT images and inaccuracies in tissue identification. Model-based compensation techniques have the potential to account for the distortion effects. This approach requires only a small number of parameters and is applicable to a wide range of spectra and count rates, but it needs an accurate model of the spectral distortions occurring in PCDs. The purpose of this study was to develop a model of those spectral distortions and to evaluate the model using a PCD (model DXMCT-1; DxRay, Inc., Northridge, CA) and various x-ray spectra in a wide range of count rates. Methods: The authors hypothesize that the complex phenomena of spectral distortions can be modeled by: (1) separating them into count-rate independent factors that we call the spectral response effects (SRE), and count-rate dependent factors that we call the pulse pileup effects (PPE), (2) developing separate models for SRE and PPE, and (3) cascading the SRE and PPE models into a combined SRE+PPE model that describes PCD distortions at both low and high count rates. The SRE model describes the probability distribution of the recorded spectrum, with a photo peak and a continuum tail, given the incident photon energy. Model parameters were obtained from calibration measurements with three radioisotopes and then interpolated linearly for other energies. The PPE model used was developed in the authors previous work [K. Taguchi et al., Modeling the performance of a photon counting x-ray detector for CT: Energy response and pulse pileup effects, Med. Phys. 38(2), 10891102 (2011)]. The

  1. February 14

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

    14 February 14 Attending: Eric Hiroshi Patrick Mike Lisa Iwona Larry Utilization: Cluster has not been completely full due to ALICE not running much. There will be an ALICE troubleshooting session later in the week. Outages: eliza1 has recovered - Dell rewrote headers on all 45 drives. eliza2 firmware was upgraded as well. eliza8 was fixed yesterday. Upcoming downtimes: Bestman to be restarted 2/21/12 at 9am. Procurements: ALICE is buying more compute power. Groups can test using /project for

  2. October 11

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    11 October 11 Attending: Eric Mike Larry Iwona JeffA Utilization: Cluster is full, almost completely STAR+ALICE. Still about 1400 cores with ALICE using about 900 all the time. Outages: Bestman went down due to memory leak so it was upgraded to the latest version and restarted. Monitoring was put in place so we'll get a warning before this occurs next time. Upcoming Downtimes: Nothing scheduled. Procurements/New Hardware: 20 new nodes should be in place by the 17th and the remaining hardware is

  3. September 28

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    28 September 28 PDSF Users Meeting 9/28/10 Attending: Eric and Jay from PDSF and users Ke Han, Joanna, Marjorie, Thomas, Shane. Cluster status: Cluster has been pretty full last few weeks, mostly STAR and ALICE. There are a lot of astrogfs jobs pending but they have no share so they don't run. Outages: NERSC-wide outage recently due to a security problem. PDSF outage this morning - logins were hanging. The memory problem was fixed but another kernel patch is needed. Upcoming downtimes: Nothing

  4. January 31

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    1 January 31 Attending: Eric Iwona JeffP Keith Alex Hiroshi Larry Jim JeffA Lisa Ernst Security: Jim Mellander discussed how connections to NERSC are managed. This was because now and then legitimate connections get blocked and that can be hard for users to diagnose. Utilization: Cluster has been full with some fluctuations due to ALICE issues with /tmp usage. Outages: There have been slowdowns related to filesystem manager overloads. This will be addressed in the upcoming downtime 2/3. Upcoming

  5. July 20

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    20 July 20 PDSF Users Meeting 7/20/10 Attending: Eric, Iwona and Jay from PDSF and users Andrei, Jeff P., Tom, Ke Han, Jeff A. Cluster status: Utilization has been moderate. Outages: Tere were problems with pdsf4 due to heavy io. Upcoming downtimes: The big shutdown is now scheduled to start July 27 at 7am and last through Friday afternoon the 30th. New hardware: Jay is waiting for reply frrom MS about ATLAS storage. ALICE storage expected to arrive soon. Other Topics: - We hit the inode limit

  6. Microsoft Word - Connecting Variable Generating Resources to...

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    and down simultaneously, frequently resulting in large, unscheduled swings in wind generation. This causes BPA to increase or back off generation in like amounts in real time to...

  7. Spectral Asymmetry Due to Magnetic Coordinates

    SciTech Connect (OSTI)

    Park, Jong-kyu; Boozer, Allen H.; Menard, Jonathan E.

    2008-05-06

    The use of magnetic coordinates is ubiquitous in toroidal plasma physics, but the distortion in Fourier spectra produced by these coordinates is not well known. A spatial symmetry of the field is not always represented by a symmetry in the Fourier spectrum when magnetic coordinates are used because of the distortion of the toroidal angle. The practical importance of spectral distortion is illustrated with a tokamak example.

  8. Fourth Friday Cancelled due to Thanksgiving Holidays

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    Fourth Annual Post Competition Accountability Report Fourth Annual Post Competition Accountability Report LM has completed its fourth annual Post Competition Accountability Report - Office of Legacy Management's High Performing Organization: Fiscal Year (FY) 2015 Fourth Annual Post Competition Accountability Report (279.26 KB) More Documents & Publications First Annual Post Competition Accountability Report Third Annual Post Competition Accountability Report Second Annual Post Competition

  9. 2014 NERSC allocation requests due September 22

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    Process) Request Form. ERCAP is accessed through the NERSC Information Management (NIM) system at https:nim.nersc.gov. Information on how to fill out the ERCAP Request...

  10. 2013 Allocation Request Submissions Due September 28

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    Process) Request Form. ERCAP is accessed through the NERSC Information Management (NIM) system at http:nim.nersc.gov. See 2013 Allocation Requests. Subscribe via RSS...