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Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
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1

Two problems in Classical Mechanics  

E-Print Network (OSTI)

A problem about the present structure of dimensional analysis, and another one about the differences between solids and fluids are suggested. Both problems appear to have certain foundational aspects.

E. E. Rosinger

2004-07-09T23:59:59.000Z

2

Effect of multiple repairs in girth welds of pipelines on the mechanical properties  

Science Conference Proceedings (OSTI)

This work presents the results of multiple weld repairs in the same area in seamless API X-52 microalloyed steel pipe. Four conditions of shielded metal arc welding repairs and one as-welded specimen of the girth weld were characterized to determine changes in the microstructure, grain size in the heat affected zone, and to evaluate their effect on the mechanical properties of the weld joints. The mechanical properties by means of tension tests, Charpy-V impact resistance and Vickers hardness of the welds were analyzed. The results indicate that significant changes are not generated in the microstructural constituents of the heat affected zone. Grain growth in the heat affected zone at the specimen mid-thickness with the number of repairs was observed. Tensile strength of the weld joints meets the requirement of the API 1104 standard even after the fourth weld repair. Significant reduction in Charpy-V impact resistance with the number of weld repairs was found when the notch location was in the intersection of the fusion line with the specimen mid-thickness. A significant increase in the Vickers hardness of the heat affected zone occurred after the first repair and a gradual decrease in the Vickers hardness occurred as the number of repairs increases.

Vega, O.E.; Hallen, J.M. [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, Laboratorios Pesados de Metalurgia, UPALM, Zacatenco, C.P. 07738, Mexico D.F. (Mexico); Villagomez, A. [Construcciones Maritimas Mexicanas, CMM-PROTEXA, Av. Periferica s/n, Fracc. Lomas de Holche, C.P. 24120, Cd. del Carmen, Campeche (Mexico); Contreras, A. [Instituto Mexicano del Petroleo, Investigacion en Ductos, Corrosion y Materiales, Eje Central Lazaro Cardenas Norte 152 Col. San Bartolo Atepehuacan, C.P. 07730, Mexico D.F. (Mexico)], E-mail: acontrer@imp.mx

2008-10-15T23:59:59.000Z

3

Matroids, secretary problems, and online mechanisms  

Science Conference Proceedings (OSTI)

We study a generalization of the classical secretary problem which we call the "matroid secretary problem". In this problem, the elements of a matroid are presented to an online algorithm in random order. When an element arrives, the algorithm observes ...

Moshe Babaioff; Nicole Immorlica; Robert Kleinberg

2007-01-01T23:59:59.000Z

4

CLASSICAL MECHANICS: THE THREE-BODY PROBLEM ZI CHONG KAO  

E-Print Network (OSTI)

CLASSICAL MECHANICS: THE THREE-BODY PROBLEM ZI CHONG KAO Abstract. The Three-Body Problem is one of the oldest unsolved problems of classical mechanics. It arose as a natural extension of the Two-Body Prob of numerous techniques in classical mechan- ics as well as dynamical systems. Understanding the Three

May, J. Peter

5

Quantum mechanics problems in observer's mathematics  

Science Conference Proceedings (OSTI)

This work considers the ontology, guiding equation, Schrodinger's equation, relation to the Born Rule, the conditional wave function of a subsystem in a setting of arithmetic, algebra and topology provided by Observer's Mathematics (see www.mathrelativity.com). Observer's Mathematics creates new arithmetic, algebra, geometry, topology, analysis and logic which do not contain the concept of continuum, but locally coincide with the standard fields. Certain results and communications pertaining to solutions of these problems are provided. In particular, we prove the following theorems: Theorem I (Two-slit interference). Let {Psi}{sub 1} be a wave from slit 1, {Psi}{sub 2} - from slit 2, and {Psi} = {Psi}{sub 1}+{Psi}{sub 2}. Then the probability of {Psi} being a wave equals to 0.5. Theorem II (k-bodies solution). For W{sub n} from m-observer point of view with m>log{sub 10}((2 Multiplication-Sign 10{sup 2n}-1){sup 2k}+1), the probability of standard expression of Hamiltonian variation is less than 1 and depends on n,m,k.

Khots, Boris; Khots, Dmitriy [Compressor Controls Corp, Des Moines, Iowa (United States); iMath Consulting LLC, Omaha, Nebraska (United States)

2012-11-06T23:59:59.000Z

6

Advanced Nuclear Technology: Reduction of American Society of Mechanical Engineers III Weld Fabrication Repairs--Fitness for Purpose  

Science Conference Proceedings (OSTI)

This report provides alternative acceptance criteria to existing American Society of Mechanical Engineers (ASME) Section III acceptance criteria for fabrication welds. The objective is to avoid unnecessary repairs of Class 1 and Class 2 full-penetration butt welds. The bases for the project are threefold: 1) the repair of fabrication flaws is known to contribute to failures during subsequent service, 2) the ASME Code does not currently provide fitness-for-service assessment of fabrication flaws, and 3) a...

2010-11-15T23:59:59.000Z

7

INTERNAL REPAIR OF PIPELINES  

Science Conference Proceedings (OSTI)

The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. In lieu of a field installation on an abandoned pipeline, a preliminary nondestructive testing protocol is being developed to determine the success or failure of the fiber-reinforced liner pipeline repairs. Optimization and validation activities for carbon-fiber repair methods are ongoing.

Bill Bruce; Nancy Porter; George Ritter; Matt Boring; Mark Lozev; Ian Harris; Bill Mohr; Dennis Harwig; Robin Gordon; Chris Neary; Mike Sullivan

2005-07-20T23:59:59.000Z

8

Monte-carlo calculations for some problems of quantum mechanics  

Science Conference Proceedings (OSTI)

The Monte-Carlo technique for the calculations of functional integral in two one-dimensional quantum-mechanical problems had been applied. The energies of the bound states in some potential wells were obtained using this method. Also some peculiarities in the calculation of the kinetic energy in the ground state had been studied.

Novoselov, A. A., E-mail: novoselov@goa.bog.msu.ru; Pavlovsky, O. V.; Ulybyshev, M. V. [Moscow State University (Russian Federation)

2012-09-15T23:59:59.000Z

9

INTERNAL REPAIR OF PIPELINES  

Science Conference Proceedings (OSTI)

The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. The first round of optimization and validation activities for carbon-fiber repairs are complete. Development of a comprehensive test plan for this process is recommended for use in the field trial portion of this program.

Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

2004-12-31T23:59:59.000Z

10

INTERNAL REPAIR OF PIPELINES  

Science Conference Proceedings (OSTI)

The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is only marginally effective at restoring the pressure containing capabilities of pipelines. Failure pressures for larger diameter pipe repaired with a semi-circular patch of carbon fiber-reinforced composite lines were also marginally greater than that of a pipe section with un-repaired simulated damage without a liner. These results indicate that fiber reinforced composite liners have the potential to increase the burst pressure of pipe sections with external damage Carbon fiber based liners are viewed as more promising than glass fiber based liners because of the potential for more closely matching the mechanical properties of steel. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. Development of a comprehensive test plan for this process is recommended for use in the field trial portion of this program.

Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

2004-08-17T23:59:59.000Z

11

Mechanical modeling of porous oxide fuel pellet A Test Problem  

Science Conference Proceedings (OSTI)

A poro-elasto-plastic material model has been developed to capture the response of oxide fuels inside the nuclear reactors under operating conditions. Behavior of the oxide fuel and variation in void volume fraction under mechanical loading as predicted by the developed model has been reported in this article. The significant effect of void volume fraction on the overall stress distribution of the fuel pellet has also been described. An important oxide fuel issue that can have significant impact on the fuel performance is the mechanical response of oxide fuel pellet and clad system. Specifically, modeling the thermo-mechanical response of the fuel pellet in terms of its thermal expansion, mechanical deformation, swelling due to void formation and evolution, and the eventual contact of the fuel with the clad is of significant interest in understanding the fuel-clad mechanical interaction (FCMI). These phenomena are nonlinear and coupled since reduction in the fuel-clad gap affects thermal conductivity of the gap, which in turn affects temperature distribution within the fuel and the material properties of the fuel. Consequently, in order to accurately capture fuel-clad gap closure, we need to account for fuel swelling due to generation, retention, and evolution of fission gas in addition to the usual thermal expansion and mechanical deformation. Both fuel chemistry and microstructure also have a significant effect on the nucleation and growth of fission gas bubbles. Fuel-clad gap closure leading to eventual contact of the fuel with the clad introduces significant stresses in the clad, which makes thermo-mechanical response of the clad even more relevant. The overall aim of this test problem is to incorporate the above features in order to accurately capture fuel-clad mechanical interaction. Because of the complex nature of the problem, a series of test problems with increasing multi-physics coupling features, modeling accuracy, and complexity are defined with the objective of accurate simulation of fuel-clad mechanical interaction subjected to a wide-range of thermomechanical stimuli.

Nukala, Phani K [ORNL; Barai, Pallab [ORNL; Simunovic, Srdjan [ORNL; Ott, Larry J [ORNL

2009-10-01T23:59:59.000Z

12

Enzymological and Structural Studies of the Mechanism of Promiscuous Substrate Recognition by the Oxidative DNA Repair Enzyme AlkB  

SciTech Connect

Promiscuous substrate recognition, the ability to catalyze transformations of chemically diverse compounds, is an evolutionarily advantageous, but poorly understood phenomenon. The promiscuity of DNA repair enzymes is particularly important, because it enables diverse kinds of damage to different nucleotide bases to be repaired in a metabolically parsimonious manner. We present enzymological and crystallographic studies of the mechanisms underlying promiscuous substrate recognition by Escherichia coli AlkB, a DNA repair enzyme that removes methyl adducts and some larger alkylation lesions from endocyclic positions on purine and pyrimidine bases. In vitro Michaelis-Menten analyses on a series of alkylated bases show high activity in repairing N1-methyladenine (m1A) and N3-methylcytosine (m3C), comparatively low activity in repairing 1,N6-ethenoadenine, and no detectable activity in repairing N1-methylguanine or N3-methylthymine. AlkB has a substantially higher kcat and Km for m3C compared with m1A. Therefore, the enzyme maintains similar net activity on the chemically distinct substrates by increasing the turnover rate of the substrate with nominally lower affinity. Cocrystal structures provide insight into the structural basis of this 'kcat/Km compensation,' which makes a significant contribution to promiscuous substrate recognition by AlkB. In analyzing a large ensemble of crystal structures solved in the course of these studies, we observed 2 discrete global conformations of AlkB differing in the accessibility of a tunnel hypothesized to control diffusion of the O2 substrate into the active site. Steric interactions between a series of protein loops control this conformational transition and present a plausible mechanism for preventing O2 binding before nucleotide substrate binding.

Yu, B.; Hunt, J

2009-01-01T23:59:59.000Z

13

On a solvability of hydro-mechanical problem based on contact problem with visco-plastic friction in Bingham rheology  

Science Conference Proceedings (OSTI)

This paper deals with the solvability and numerical solution of contact problem with a local visco-plastic friction in the visco-plastic Bingham rheology. The model problem discussed represents a simple hydro-mechanical model of the global project on ... Keywords: Bingham rheology, Contact problems with friction, FEM, Geomechanics, Hydromechanics, Variational inequalities, Visco-plasticity

Ji?í Nedoma; Luboš Tomášek

2008-08-01T23:59:59.000Z

14

Comparison of problem model change mechanisms issued from CSP and TRIZ  

E-Print Network (OSTI)

1 Comparison of problem model change mechanisms issued from CSP and TRIZ RRoollaanndd DDee GGuuiioo satisfaction problem (CSP), on the other hand. Keywords: over-constrained problems, dialectical methods issued from CSP and TRIZ 2 · a set of evaluation parameters, which represent the objective of the problem

Paris-Sud XI, Université de

15

Shape-invariance and Exactly Solvable Problems in Quantum Mechanics  

E-Print Network (OSTI)

Algebraic approach to the integrability condition called shape invariance is briefly reviewed. Various applications of shape-invariance available in the literature are listed. A class of shape-invariant bound-state problems which represent two-level systems are examined. These generalize the Jaynes-Cummings Hamiltonian. Coherent states associated with shape-invariant systems are discussed. For the case of quantum harmonic oscillator the decomposition of identity for these coherent states is given. This decomposition of identity utilizes Ramanujan's integral extension of the beta function.

A. B. Balantekin

2003-09-15T23:59:59.000Z

16

Welding and Repair Technology Center: Repair Welding Handbook  

Science Conference Proceedings (OSTI)

During the life of a power plant, it often becomes necessary to perform weld repairs of various materials in order to continue safe operation. Much work has been completed in this area to assist utilities with choosing appropriate repair techniques based on the materials involved and the damage mechanism that makes the repair necessary. This report captures in one resource a variety of repair methods that have been proven to be effective.

2012-05-14T23:59:59.000Z

17

On inverse problems in electromagnetic field in classical mechanics at fixed energy  

E-Print Network (OSTI)

In this paper, we consider inverse scattering and inverse boundary value problems at sufficiently large and fixed energy for the multidimensional relativistic and nonrelativistic Newton equations in a static external electromagnetic field $(V,B)$, $V\\in C^2,$ $B\\in C^1$ in classical mechanics. Developing the approach going back to Gerver-Nadirashvili 1983's work on an inverse problem of mechanics, we obtain, in particular, theorems of uniqueness.

Alexandre Jollivet

2007-01-04T23:59:59.000Z

18

Safety, Capacity, Maintenance and Major Repairs (SCMMR) ...  

Science Conference Proceedings (OSTI)

... repairing and replacing aging mechanical and electrical ... and replacing or upgrading site utility systems; ... will avoid costly infrastructure failures such ...

2010-10-05T23:59:59.000Z

19

Solving Nonlinear Solid Mechanics Problems with the Jacobian-Free Newton Krylov Method  

Science Conference Proceedings (OSTI)

The solution of the equations governing solid mechanics is often obtained via Newton's method. This approach can be problematic if the determination, storage, or solution cost associated with the Jacobian is high. These challenges are magnified for multiphysics applications with many coupled variables. Jacobian-free Newton-Krylov (JFNK) methods avoid many of the difficulties associated with the Jacobian by using a finite difference approximation. BISON is a parallel, object-oriented, nonlinear solid mechanics and multiphysics application that leverages JFNK methods. We overview JFNK, outline the capabilities of BISON, and demonstrate the effectiveness of JFNK for solid mechanics and solid mechanics coupled to other PDEs using a series of demonstration problems.

J. D. Hales; S. R. Novascone; R. L. Williamson; D. R. Gaston; M. R. Tonks

2012-06-01T23:59:59.000Z

20

On Problem of Mass Origin and Self-Energy Divergence in Relativistic Mechanics and Gravitational Physics  

E-Print Network (OSTI)

The classical problem of self-energy divergence was studied in the framework of Lagrangian formulation of Relativistic Mechanics. The conclusion was made that a revision of mass-energy concept is needed for the development of singularity-free gravitational and electromagnetic field theory. Perspectives of the development of unified field theory are discussed.

Anatoli Vankov

2003-11-20T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

The fundamental obscurity in quantum mechanics. Could the problem be considered universal?  

E-Print Network (OSTI)

The contemporary controversy about the fundamental obscurity in quantum mechanics keeps on the old one about the aim of science, which was between the founders of the quantum theory. The orthodox quantum mechanics could be created only at the cost of renunciation of reality as the aim of natural science. The description only of phenomena, i.e. results of observation, should not be universal if no one believes that these phenomena are manifestation of a unique reality. Such belief concerning quantum mechanics is quite unacceptable because of irremediably conflict with special relativity. Nevertheless the quantum mechanics was developed and apprehended by most physicists as a universal theory of a quantum world. This fundamental discrepancy between the essence of the orthodox quantum mechanics and its history of development and studying has resulted both to an illusion about the aim of its description among most physicists and to the consideration of its fundamental obscurity as a universal problem among experts in quantum foundation. The aim of this paper is to show that quantum phenomena can not be described universally. It is indicated that rather the Schrodinger's than Born's interpretation of the wave function is valid for description of many quantum phenomena. The fundamental obscurity with which we are faced at the description, for example, macroscopic quantum phenomena differs fundamentally from the one with which the founders of the quantum theory were faced on atomic level.

A. V. Nikulov

2010-12-20T23:59:59.000Z

22

Repairs of Deaerators  

Science Conference Proceedings (OSTI)

This report provides a brief background of deaerator operation, including types of deaerators. Materials of construction are reviewed along with inspection, failure mechanisms, and repair methods. Some general information is provided to calculate minimum wall to see if deaerators are suitable for continued operation with defects in place.

2004-06-29T23:59:59.000Z

23

Localized Hardfacing Repair Techniques, RRAP45  

Science Conference Proceedings (OSTI)

Hardfacing overlays provide a hard, corrosive-resistant wear surface for critical valve, pump, and other component materials susceptible to one or more of the various wear mechanisms. As a result of being hard, these materials are also difficult to deposit and even more difficult to repair. When faced with a repair, owners either replace the hardfaced component or go through a time-consuming and difficult repair task. This report presents repair practices utilized by hardfacing alloy manufacturers, valve...

1997-12-19T23:59:59.000Z

24

Thermo-mechanical fatigue of polycrystalline, directionally solidified and single crystal nickel base superalloys repaired by laser beam welding.  

E-Print Network (OSTI)

??The low cycle thermo-mechanical fatigue of laser beam welded conventionally cast Inconel 738, directionally solidified René 80 and single crystal René N5 has been evaluated.… (more)

Durocher, Jonathan

2013-01-01T23:59:59.000Z

25

Pure States, Mixed States and Hawking Problem in Generalized Quantum Mechanics  

E-Print Network (OSTI)

This paper is the continuation of a study into the information paradox problem started by the author in his earlier works. As previously, the key instrument is a deformed density matrix in quantum mechanics of the early universe. It is assumed that the latter represents quantum mechanics with fundamental length. It is demonstrated that the obtained results agree well with the canonical viewpoint that in the processes involving black holes pure states go to the mixed ones in the assumption that all measurements are performed by the observer in a well-known quantum mechanics. Also it is shown that high entropy for Planck remnants of black holes appearing in the assumption of the Generalized Uncertainty Relations may be explained within the scope of the density matrix entropy introduced by the author previously. It is noted that the suggested paradigm is consistent with the Holographic Principle. Because of this, a conjecture is made about the possibility for obtaining the Generalized Uncertainty Relations from the covariant entropy bound at high energies in the same way as R. Bousso has derived Heisenberg uncertainty principle for the flat space.

A. E. Shalyt-Margolin

2004-05-13T23:59:59.000Z

26

Enhancement of mechanical strength of TiO{sub 2}/high-density polyethylene composites for bone repair with silane-coupling treatment  

SciTech Connect

Mechanical properties of composites made up of high-density polyethylene (HDPE) and silanated TiO{sub 2} particles for use as a bone-repairing material were investigated in comparison with those of the composites of HDPE with unsilanized TiO{sub 2} particles. The interfacial morphology and interaction between silanated TiO{sub 2} and HDPE were analyzed by means of Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). The absorption in spectral bands related to the carboxyl bond in the silane-coupling agent, the vinyl group in the HDPE, and the formation of the ether bond was studied in order to assess the influence of the silane-coupling agent. The SEM micrograph showed that the 'bridging effect' between HDPE and TiO{sub 2} was brought about by the silane-coupling agent. The use of the silane-coupling agent and the increase of the hot-pressing pressure for shaping the composites facilitated the penetration of polymer into cavities between individual TiO{sub 2} particles, which increased the density of the composite. Therefore, mechanical properties such as bending yield strength and Young's modulus increased from 49 MPa and 7.5 GPa to 65 MPa and 10 GPa, respectively, after the silane-coupling treatment and increase in the hot-pressing pressure.

Hashimoto, Masami [Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya 456-8587 (Japan)]. E-mail: masami@jfcc.or.jp; Takadama, Hiroaki [Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya 456-8587 (Japan)]. E-mail: takadama@jfcc.or.jp; Mizuno, Mineo [Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atsuta-ku, Nagoya 456-8587 (Japan)]. E-mail: mizuno@jfcc.or.jp; Kokubo, Tadashi [Research Institute for Science and Technology, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501 (Japan)]. E-mail: kokubo@isc.chubu.ac.jp

2006-03-09T23:59:59.000Z

27

Philosophy of Mind and the Problem of Free Will in the Light of Quantum Mechanics.  

E-Print Network (OSTI)

Foundations of Quantum Mechanics. (Princeton UniversityMind, Matter, and Quantum Mechanics, (Springer, Berlin & NewMindful Universe: Quantum Mechanics and the Participating

Stapp, Henry P

2008-01-01T23:59:59.000Z

28

Microsoft PowerPoint - Powerpoint_WebRepair.ppt [Compatibility...  

NLE Websites -- All DOE Office Websites (Extended Search)

strand break repair is usually error free. g p y * Double strand breaks can be either error free or error t i i hi h t prone, containing a high error rate. Mechanisms of Repair...

29

Fan Repair Guideline  

Science Conference Proceedings (OSTI)

The successful repair of a fan component is affected by a number of different factors. These include correctly assessing the root cause of failure, determining the best repair option, implementation of proper repair procedures, and compliance with applicable codes and standards. However, in many situations the proper solution is not clearly evident. The purpose of this document is to provide guidance in the area of induced draft / forced draft fan repair. Specifically, this document deals with the repair...

2002-08-15T23:59:59.000Z

30

Class of model problems in three-body quantum mechanics that admit exact solutions  

Science Conference Proceedings (OSTI)

An approach to solving scattering problems in three-body systems for cases where the mass of one of the particles is extremely small in relation to the masses of the other two particles and where the pair potentials of interaction between the particles involved are separable is developed. Exact analytic solutions to such model problems are found for the scattering of a light particle on two fixed centers and on two interacting heavy particles. It is shown that new resonances and a dynamical resonance enhancement may appear in a three-body system.

Takibayev, N. Zh., E-mail: teta@nursat.kz [Abay Kazakh National Pedagogical University (Kazakhstan)

2008-03-15T23:59:59.000Z

31

Welding and Repair Technology Center: Repair Technology for Degraded Pressure Vessel and Heat Exchanger Shells  

Science Conference Proceedings (OSTI)

BackgroundPressure vessels and heat exchangers are subject to a number of degradation mechanisms that can cause thinning of component walls and deterioration of internal components. With many repair options available, the Electric Power Research Institute (EPRI) Welding and Repair Technology Center (WRTC) has developed this report to assist operations and engineering personnel who are faced with defective or failed vessel components. Many available repair options allow ...

2013-10-30T23:59:59.000Z

32

Rapid road repair vehicle  

DOE Patents (OSTI)

Disclosed is a rapid road repair vehicle capable of moving over a surface to be repaired at near normal posted traffic speeds to scan for and find at the high rate of speed, imperfections in the pavement surface, prepare the surface imperfection for repair by air pressure and vacuum cleaning, applying a correct amount of the correct patching material to effect the repair, smooth the resulting repaired surface, and catalog the location and quality of the repairs for maintenance records of the road surface. The rapid road repair vehicle can repair surface imperfections at lower cost, improved quality, at a higher rate of speed than was not heretofor possible, with significantly reduced exposure to safety and health hazards associated with this kind of road repair activities in the past. 2 figs.

Mara, L.M.

1998-05-05T23:59:59.000Z

33

Philosophy of mind and the problem of free will in the light of quantum mechanics  

E-Print Network (OSTI)

Defects occasioned by the advent of quantum mechanics are described in detail of recent arguments by John Searle and by Jaegwon Kim pertaining to the question of the complete reducibility to the physical of the apparent capacity of a person's conscious thoughts to affect the behaviour of that person's physically described brain.

Henry P. Stapp

2008-05-01T23:59:59.000Z

34

Philosophy of Mind and the Problem of FreeWill in the Light of Quantum Mechanics.  

Science Conference Proceedings (OSTI)

Arguments pertaining to the mind-brain connection and to the physical effectiveness of our conscious choices have been presented in two recent books, one by John Searle, the other by Jaegwon Kim. These arguments are examined, and it is argued that the difficulties encountered arise from a defective understanding and application of a pertinent part of contemporary science, namely quantum mechanics.

Stapp, Henry; Stapp, Henry P

2008-04-01T23:59:59.000Z

35

Repairing structurally complex data  

Science Conference Proceedings (OSTI)

We present a novel algorithm for repairing structurally complex data. Given an assertion that represents desired structural integrity constraints and a structure that violates them, the algorithm performs repair actions that mutate the given structure ...

Sarfraz Khurshid; Iván García; Yuk Lai Suen

2005-08-01T23:59:59.000Z

36

New mechanism of solution of the $kT$-problem in magnetobiology  

E-Print Network (OSTI)

The effect of ultralow-frequency or static magnetic and electric fields on biological processes is of huge interest for researchers due to the resonant change of the intensity of biochemical reactions although the energy in such fields is small. A simplified model to study the effect of the weak magnetic and electrical fields on fluctuation of the random ionic currents in blood and to solve the $k_BT$ problem in magnetobiology is suggested. The analytic expression for the kinetic energy of the molecules dissolved in certain liquid media is obtained. The values of the magnetic field leading to resonant effects in capillaries are estimated. The numerical estimates showed that the resonant values of the energy of molecular in the capillaries and aorta are different: under identical conditions a molecule of the aorta gets $10^{-9}$ times less energy than the molecules in blood capillaries. So the capillaries are very sensitive to the resonant effect, with an approach to the resonant value of the magnetic field strength, the average energy of the molecule localized in the capillary is increased by several orders of magnitude as compared to its thermal energy, this value of the energy is sufficient for the deterioration of the chemical bonds.

Zakirjon Kanokov; Juern W. P. Schmelzer; Avazbek K. Nasirov

2009-05-16T23:59:59.000Z

37

Repairable chip bonding/interconnect process  

DOE Patents (OSTI)

A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules is disclosed. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder. 10 figs.

Bernhardt, A.F.; Contolini, R.J.; Malba, V.; Riddle, R.A.

1997-08-05T23:59:59.000Z

38

Repairable chip bonding/interconnect process  

DOE Patents (OSTI)

A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder.

Bernhardt, Anthony F. (Berkeley, CA); Contolini, Robert J. (Livermore, CA); Malba, Vincent (Livermore, CA); Riddle, Robert A. (Tracy, CA)

1997-01-01T23:59:59.000Z

39

Checkpoint repair for out-of-order execution machines  

Science Conference Proceedings (OSTI)

Out-of-order execution and branch prediction are two mechanisms that can be used profitably in the design of Supercomputers to increase performance. Unfortunately this means there must be some kind of repair mechanism, since situations do occur that ...

W. W. Hwu; Y. N. Patt

1987-06-01T23:59:59.000Z

40

An engineering analysis of natural and biomimetic self-repair processes for solar energy harvesting  

E-Print Network (OSTI)

Plants have evolved highly sophisticated mechanisms of self-repair to regenerate proteins that become photo-damaged over time. Key to this self-repair process is the reversible self-assembly of protein complexes, which is ...

Boghossian, Ardemis A. (Ardemis Anoush)

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

HRSG Material Selection and Repair Guidelines  

Science Conference Proceedings (OSTI)

The number of failures in heat recovery steam generator (HRSG) components has been quite high during the past decade. Many of these failures are attributed to poor design, improper operation, poor fabrication, or poor installation practices. This report provides repair practices and procedures currently being used to correct a number of these problems. It also identifies domestic and international materials commonly employed.

2004-03-31T23:59:59.000Z

42

The mechanism of recA polA lethality: Suppression by RecA-independent recombination repair activated by the lexA(Def) mutation in Escherichia coli  

SciTech Connect

The mechanism of recA polA lethality in Escherichia coli has been studied. Complementation tests have indicated that both the 5{prime} {yields} 3{prime} exonuclease and the polymerization activities of DNA polymerase I are essential for viability in the absence of RecA protein, whereas the viability and DNA replication of DNA polymerase I-defective cells depend on the recombinase activity of RecA. An alkaline sucrose gradient sedimentation analysis has indicated that RecA has only a minor role in Okazaki fragment processing. Double-strand break repair is proposed for the major role of RecA in the absence of DNA polymerase I. The lexA(Def)::Tn5 mutation has previously been shown to suppress the temperature-sensitive growth of recA200(Ts) polA25::spc mutants. The lexA(Def) mutation can alleviate impaired DNA synthesis in the recA200(Ts) polA25::spc mutant cells at the restrictive temperature. recF{sup +} is essential for this suppression pathway, recJ and recQ mutations have minor but significant adverse effects on the suppression. The recA200(Ts) allele in the recA200(Ts) polA25::spc lexA(Def) mutant can be replaced by {Delta}recA, indicating that the lexA(Def)-induced suppression is RecA independent. lexA(Def) reduces the sensitivity of {Delta}recA polA25::spc cells to UV damage by {approximately}10{sup 4}-fold. lexA(Def) also restores P1 transduction proficiency to the {Delta}recA polA25::spc mutant to a level that is 7.3% of the recA{sup +} wild type. These results suggest that lexA(Def) activates a RecA-independent, RecF-dependent recombination repair pathway that suppresses the defect in DNA replication in recA polA double mutants. 52 refs., 7 figs., 5 tabs.

Cao, Yang; Kogoma, Tokio [Univ. of New Mexico Health Sciences Center, Albuquerque, NM (United States)

1995-04-01T23:59:59.000Z

43

LASER ENGINEERED NET SHAPING FOR REPAIR AND HYDROGEN COMPATIBILITY  

DOE Green Energy (OSTI)

A method to repair mismatched or damaged components using Laser Engineered Net Shaping{sup R} (LENS) technology to apply material was investigated for its feasibility for components exposed to hydrogen. The mechanical properties of LENS bulk materials were also tested for hydrogen compatibility. The LENS process was used to repair simulated and actual mismachined components. These sample components were hydrogen charged and burst tested in the as-received, as-damaged, and as-repaired conditions. The testing showed that there was no apparent additional deficiency associated with hydrogen charging compared to the repair technique. The repair techniques resulted in some components meeting the requirements while others did not. Additional procedure/process development is required prior to recommending production use of LENS.

Korinko, P.; Adams, T.

2011-08-05T23:59:59.000Z

44

An integrated finite element and finite volume code to solve thermo-hydro-mechanical problems in porous media.  

E-Print Network (OSTI)

??The objective of the thesis is to provide a fully coupled thermo-hydro-mechanical (THM) tool, T2STR, which enables quantitative understanding and prediction of thermal as well… (more)

Gosavi, Shekhar Vishwanath

2006-01-01T23:59:59.000Z

45

Geothermal Well Maintenance and Repair in Cerro Prieto  

DOE Green Energy (OSTI)

When the first well is drilled at a geothermal field, procedures for the cleaning, repair, and control of wells should be established. This aspect will be increasingly important as more wells are drilled. Equipment, tools and techniques need to be improved to achieve economic and safe results. Different systems have been developed and applied in maintenance of wells, in problems of casing incrustations, repairs, plugging, and well control. These systems should be improved, even though they have been reasonably satisfactory to date.

Aguirre, B. D.; Blanco, F. V.

1981-01-01T23:59:59.000Z

46

A tale of three actuators: how mechanics, business models and position sensing affect different mechatronic servo problems  

Science Conference Proceedings (OSTI)

Students studying control problems often learn a lot of wondrous algorithms that impart near mythical properties to the systems that they are applied to. At least this is how it works in theory and simulation. In practice, however, a through understanding ...

Daniel Y. Abramovitch

2009-06-01T23:59:59.000Z

47

Solution of a three-body problem in quantum mechanics using sparse linear algebra on parallel computers  

Science Conference Proceedings (OSTI)

A complete description of two outgoing electrons following an ionizing collision between a single electron and an atom or molecule has long stood as one of the unsolved fundamental problems in quantum collision theory. In this paper we describe our use ...

Mark Baertschy; Xiaoye Li

2001-11-01T23:59:59.000Z

48

Troubleshooting, Maintaining, and Repairing Personal Computers: A Technician's Guide  

Science Conference Proceedings (OSTI)

From the Publisher:Efficient, cost-effective troubleshooting and repair techniques in the ultimate hands-on reference for technicians. With this book and your technical skills, there is no computer problem you can't correct. You'll find nearly 400 problems ...

Stephen J. Bigelow

1995-11-01T23:59:59.000Z

49

Quantum mechanical analogue of the zeroth law of thermodynamics. (On the problem of incorporating Thermodynamics into Quantum Theory)  

E-Print Network (OSTI)

This approach to the incorporation of stochastic thermodynamics into quantum theory is based on the conception of consistent inclusion of the holistic stochastic environmental influence described by wave functions of the arbitrary vacuum, which was proposed in our paper previously. In this study, we implement the possibility of explicitly incorporating the zeroth law of stochastic thermodynamics in the form of the saturated Schr\\"odinger uncertainty relation into quantum theory. This allows comparatively analyzing the sets of states of arbitrary vacuums, namely, squeezed coherent states (SCSs) and correlated coherent states (CCSs). In addition, we compare the results of the construction of stochastic thermodynamics using SCSs and TCCSs with the versions involving the incorporation of thermodynamics into quantum theory developed previously and based on thermofield dynamics and quantum statistical mechanics.

O. N. Golubjeva; A. D. Sukhanov

2013-03-25T23:59:59.000Z

50

Polymer nanocomposites for high-temperature composite repair  

SciTech Connect

A novel repair agent for resin-injection repair of advanced high temperature composites was developed and characterized. The repair agent was based on bisphenol E cyanate ester (BECy) and reinforced with alumina nanoparticles. To ensure good dispersion and compatibility with the BECy matrix in nanocomposites, the alumina nanoparticles were functionalized with silanes. The BECy nanocomposites, containing bare and functionalized alumina nanoparticles, were prepared and evaluated for their thermal, mechanical, rheological, and viscoelastic properties. The monomer of BECy has an extremely low viscosity at ambient temperature, which is good for processability. The cured BECy polymer is a highly cross-linked network with excellent thermal mechanical properties, with a high glass transition temperature (T{sub g}) of 270 C and decomposition temperature above 350 C. The incorporation of alumina nanoparticles enhances the mechanical and rheological properties of the BECy nanocomposites. Additionally, the alumina nanoparticles are shown to catalyze the cure of BECy. Characterization of the nanocomposites included dynamic mechanical analysis, differential scanning calorimetry, thermogravimetric analysis, rheological and rheokinetic evaluation, and transmission electron microscopy. The experimental results show that the BECy nanocomposite is a good candidate as repair agent for resin-injection repair applications.

Sheng, Xia

2008-12-01T23:59:59.000Z

51

Breakthrough in fracture mechanics  

SciTech Connect

Fracture mechanics, the science of calculating material characteristics, stress, and flaws in plant equipment to evaluate structural integrity, usually spares the owners of nuclear power plants unnecessary expense. Instead of replacing equipment prematurely or waiting for costly, unscheduled materials failures that can take months to repair and cost thousands of dollars a day for replacement power, utilities use fracture mechanics techniques to carefully consider their options. If analyses show repair is unnecessary, plant operation can confidently be resumed. If repair is required, it can either be done immediately or, if deferrable, be scheduled for a later, more convenient outage.

Lihach, N.

1981-05-01T23:59:59.000Z

52

Industrial motor repair in the United States  

Science Conference Proceedings (OSTI)

This report characterizes the motor repair industry in the United States; summarizes current motor repair and testing practice; and identifies barriers to energy motor repair practice and recommends strategies for overcoming those barriers.

Schueler, V.; Leistner, P.; Douglass, J.

1994-09-01T23:59:59.000Z

53

Welding and Repair Technology Center: Rolled Plate Repair Guide  

Science Conference Proceedings (OSTI)

This report is intended to enlighten and assist power plant engineers in the application of welded rolled plate repairs in both nuclear and balance-of-plant piping systems. This report introduces the engineer to post-construction standards in non-nuclear industries that use these types of repair, often on a widespread basis. Related requirements in those standards are explained in order to assist the engineer in planning and designing balance-of-plant repairs using welded rolled plates in various applica...

2011-12-23T23:59:59.000Z

54

Inspect and Repair Steam Traps  

SciTech Connect

This revised ITP tip sheet on inspecting and repairing steam traps provide how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

Not Available

2006-01-01T23:59:59.000Z

55

Two-dimensional warranty repair strategy based on minimal and complete repairs  

Science Conference Proceedings (OSTI)

For repairable products, the warrantor has options in choosing the degree of repair applied to an item that has failed within the warranty period. We focus on a particular warranty repair strategy, related to the degree of the warranty repair, for non-renewing, ... Keywords: Expected warranty servicing costs, Warranty, Warranty repair strategy

S. Chukova; M. R. Johnston

2006-12-01T23:59:59.000Z

56

MAINTENANCE SHOP The shop manager, Clint Steffan has over 25 years experience in Electronic design, test, and repair in  

E-Print Network (OSTI)

MAINTENANCE SHOP The shop manager, Clint Steffan has over 25 years experience in Electronic design the capability of repairing most electronic, mechanical and electro-mechanical equipment, including refrigeration source for parts instead of buying from equipment manufacturer. Repair/recharge small refrigeration

Lajeunesse, Marc J.

57

Thermosetting Polymer-Matrix Composites for Strucutral Repair Applications  

Science Conference Proceedings (OSTI)

Several classes of thermosetting polymer matrix composites were evaluated for use in structural repair applications. Initial work involved the characterization and evaluation of woven carbon fiber/epoxy matrix composites for structural pipeline repair. Cyanate ester resins were evaluated as a replacement for epoxy in composites for high-temperature pipe repair applications, and as the basis for adhesives for resin infusion repair of high-temperature composite materials. Carbon fiber/cyanate ester matrix composites and fumed silica/cyanate ester nanocomposites were evaluated for their thermal, mechanical, viscoelastic, and rheological properties as they relate to their structure, chemistry, and processing characteristics. The bisphenol E cyanate ester under investigation possesses a high glass transition temperature, excellent mechanical properties, and unique ambient temperature processability. The incorporate of fumed silica served to enhance the mechanical and rheological properties of the polymer and reduce thermal expansion without sacrificing glass transition or drastically altering curing kinetics. Characterization of the composites included dynamic mechanical analysis, thermomechanical analysis, differential scanning calorimetry, thermogravimetric analysis, rheological and rheokinetic evaluation, and transmission electron microscopy.

William Kirby Goertzen

2007-12-01T23:59:59.000Z

58

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways  

NLE Websites -- All DOE Office Websites (Extended Search)

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps Research Institute recently applied a combination of x-ray structural, biochemical, and genetic studies to ATLs in the yeast Schizosaccharomyces pombe without and with damaged DNA. By showing how a process called non-enzymatic nucleotide flipping activates ATL-initiated DNA repair, their results may improve our understanding of genomic integrity and responses to DNA damage relevant to pathogens and cancer development.

59

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways  

NLE Websites -- All DOE Office Websites (Extended Search)

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps Research Institute recently applied a combination of x-ray structural, biochemical, and genetic studies to ATLs in the yeast Schizosaccharomyces pombe without and with damaged DNA. By showing how a process called non-enzymatic nucleotide flipping activates ATL-initiated DNA repair, their results may improve our understanding of genomic integrity and responses to DNA damage relevant to pathogens and cancer development.

60

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways  

NLE Websites -- All DOE Office Websites (Extended Search)

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps Research Institute recently applied a combination of x-ray structural, biochemical, and genetic studies to ATLs in the yeast Schizosaccharomyces pombe without and with damaged DNA. By showing how a process called non-enzymatic nucleotide flipping activates ATL-initiated DNA repair, their results may improve our understanding of genomic integrity and responses to DNA damage relevant to pathogens and cancer development.

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways  

NLE Websites -- All DOE Office Websites (Extended Search)

Protein Bridges DNA Base and Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Wednesday, 28 October 2009 00:00 Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps Research Institute recently applied a combination of x-ray structural, biochemical, and genetic studies to ATLs in the yeast Schizosaccharomyces pombe without and with damaged DNA. By showing how a process called non-enzymatic nucleotide flipping activates ATL-initiated DNA repair, their results may improve our understanding of genomic integrity and responses to DNA damage relevant to pathogens and cancer development.

62

Parsing speech repair without specialized grammar symbols  

Science Conference Proceedings (OSTI)

This paper describes a parsing model for speech with repairs that makes a clear separation between linguistically meaningful symbols in the grammar and operations specific to speech repair in the operation of the parser. This system builds a model of ...

Tim Miller; Luan Nguyen; William Schuler

2009-08-01T23:59:59.000Z

63

www.mdpi.com/journal/ijms Chromatin Dynamics during Nucleotide Excision Repair: Histones on the Move  

E-Print Network (OSTI)

Abstract: It has been a long-standing question how DNA damage repair proceeds in a nuclear environment where DNA is packaged into chromatin. Several decades of analysis combining in vitro and in vivo studies in various model organisms ranging from yeast to human have markedly increased our understanding of the mechanisms underlying chromatin disorganization upon damage detection and re-assembly after repair. Here, we review the methods that have been developed over the years to delineate chromatin alterations in response to DNA damage by focusing on the well-characterized Nucleotide Excision Repair (NER) pathway. We also highlight how these methods have provided key mechanistic insight into histone dynamics coupled to repair in mammals, raising new issues about the maintenance of chromatin integrity. In particular, we discuss how NER factors and central players in chromatin dynamics such as histone modifiers, nucleosome remodeling factors, and histone chaperones function to mobilize histones during repair.

Salomé Adam; Sophie E. Polo

2012-01-01T23:59:59.000Z

64

Charge transport-mediated recruitment of DNA repair enzymes  

E-Print Network (OSTI)

Damaged or mismatched bases in DNA can be repaired by Base Excision Repair (BER) enzymes that replace the defective base. Although the detailed molecular structures of many BER enzymes are known, how they colocalize to lesions remains unclear. One hypothesis involves charge transport (CT) along DNA [Yavin, {\\it et al.}, PNAS, {\\bf 102}, 3546, (2005)]. In this CT mechanism, electrons are released by recently adsorbed BER enzymes and travel along the DNA. The electrons can scatter (by heterogeneities along the DNA) back to the enzyme, destabilizing and knocking it off the DNA, or, they can be absorbed by nearby lesions and guanine radicals. We develop a stochastic model to describe the electron dynamics, and compute probabilities of electron capture by guanine radicals and repair enzymes. We also calculate first passage times of electron return, and ensemble-average these results over guanine radical distributions. Our statistical results provide the rules that enable us to perform implicit-electron Monte-Carlo simulations of repair enzyme binding and redistribution near lesions. When lesions are electron absorbing, we show that the CT mechanism suppresses wasteful buildup of enzymes along intact portions of the DNA, maximizing enzyme concentration near lesions.

Pak-Wing Fok; Chin-Lin Guo; Tom Chou

2008-11-18T23:59:59.000Z

65

Gas Turbine Component Repair Shop Capabilities  

Science Conference Proceedings (OSTI)

Aftermarket repair services for gas turbine OM has been undergoing continual transformation beginning with the emergence of independent shops in the 1980s. The original equipment manufacturers (OEMs) in the late 1990s began to aggressively pursue repair services. Gas turbine hot section component repair/replacement coupled with inspection/overhaul technical support has come to be offered as long-term service agreements (LTSAs). These agreements often extend from 6 to 18 years. The repair business continu...

2011-12-16T23:59:59.000Z

66

Safety, Capacity, Maintenance, and Major Repair  

Science Conference Proceedings (OSTI)

... Continue repairing or replacing aging utility systems, exhaust and air ... Continue improvements to site infrastructure, including roads, loading docks ...

2010-10-05T23:59:59.000Z

67

Advances in Hydroelectric Turbine Manufacturing and Repair  

Science Conference Proceedings (OSTI)

About this Symposium. Meeting, Materials Science & Technology 2013. Symposium, Advances in Hydroelectric Turbine Manufacturing and Repair. Sponsorship ...

68

H A&S 222d/253e: Introduction to Energy and Environment (Life Under the Pale Sun) Problem Set 1: Out: Weds. 11 April 2006 Mechanical and thermal energy  

E-Print Network (OSTI)

H A&S 222d/253e: Introduction to Energy and Environment (Life Under the Pale Sun) Spring 07 Problem Set 1: Out: Weds. 11 April 2006 Mechanical and thermal energy Back: Weds. 18 April 1. The total `marketable'energy use in the world is estimated as 4 x 1020 Joules/year. In class we converted this to watts

69

Optimal maintenance and repair policies in infrastructure management under uncertain facility deterioration rates: an adaptive control approach  

E-Print Network (OSTI)

1987. Optimal maintenance decisions for pavement management.maintenance and repair policies in infrastructure managementmanagement systems. In Section 3 we present AC formulations for the problem of ?nding optimal maintenance and

Madanat, S M; Durango, Pablo L

2001-01-01T23:59:59.000Z

70

1999 Gordon Research Conference on Mammalian DNA Repair. Final Progress Report  

SciTech Connect

This Conference will examine DNA repair as the key component in genomic surveillance that is so crucial to the overall integrity and function of mammalian cells. Recent discoveries have catapulted the field of DNA repair into a pivotal position for fundamental investigations into oncology, aging, environmental health, and developmental biology. We hope to highlight the most promising and exciting avenues of research in robust discussions at this conference. This Mammalian DNA Repair Gordon Conference differs from the past conferences in this series, in which the programs were broader in scope, with respect to topics and biological systems covered. A conference sponsored by the Genetics Society in April 1998 emphasized recombinational mechanisms for double-strand break repair and the role of mismatch repair deficiency in colorectal cancer. These topics will therefore receive somewhat less emphasis in the upcoming Conference. In view of the recent mechanistic advances in mammalian DNA repair, an upcoming comprehensive DNA repair meeting next autumn at Hilton Head; and the limited enrollment for Gordon Conferences we have decided to focus session-by-session on particular areas of controversy and/or new developments specifically in mammalian systems. Thus, the principal presentations will draw upon results from other cellular systems only to the extent that they impact our understanding of mammalian DNA repair.

1999-02-12T23:59:59.000Z

71

Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds  

Science Conference Proceedings (OSTI)

The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing.

GJ Schuster, FA Simonen, SR Doctor

2008-04-01T23:59:59.000Z

72

H A&S 222a: Introduction to Energy and Environment (Life Under the Pale Sun) Problem Set 1b: 20 April 2006 More Mechanical Energy problems (if you did not  

E-Print Network (OSTI)

speed. 6. Hybrid cars use both gasoline engines and electric motors. The gasoline powered engine is used're curious look up the stats on a Smart Car and compare). 4. ·If your SUV climbs a mountain road with slope 1 to charge the batteries and run the electric motor (using an alternator which converts mechanical energy

73

Internal pipe attachment mechanism  

DOE Patents (OSTI)

An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

1994-12-13T23:59:59.000Z

74

Gas Turbine Repair Guidelines: GE 9FA  

Science Conference Proceedings (OSTI)

For more than a decade, the Electric Power Research Institute (EPRI) has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy ...

2012-12-12T23:59:59.000Z

75

Gas Turbine Repair Guidelines: Alstom GT26  

Science Conference Proceedings (OSTI)

For more than a decade, the Electric Power Research Institute (EPRI) has been developing gas turbine hot section component repair and coating guidelines to assist utilities and power generators in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on turbine blades, vanes, and combustion hardware. The guidelines in this volume address the specific features of the Alstom GT26 gas turbine.

2011-11-03T23:59:59.000Z

76

Gas Turbine Repair Guidelines: GE 7FA  

Science Conference Proceedings (OSTI)

For more than a decade, the Electric Power Research Institute (EPRI) has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy fram...

2011-12-27T23:59:59.000Z

77

Alloy 600 Repairs with PTAW Process  

Science Conference Proceedings (OSTI)

Many utilities have Alloy 600 reactor vessel heads (RVHs) that are susceptible to primary water stress corrosion cracking (PWSCC), but have not cracked to date. This has prompted an exploration of repair and mitigation options to prevent future degradation of the RVH. Inconel 52 and Inconel 152, which are resistant to PWSCC, have been identified as potential repair alloys for Alloy 600 type repairs, and have been evaluated with the gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) pro...

2003-06-27T23:59:59.000Z

78

The Gordon conference on mammalian DNA repair  

SciTech Connect

A brief overview of the Gordon Conference on Mammalian Repair held February 1-5, 1993 in Ventura, California is presented.

Cleaver, J.E.; Smerdon, M.J.

1993-12-31T23:59:59.000Z

79

Repair of UV damaged DNA, genes and proteins of yeast and human  

Science Conference Proceedings (OSTI)

Our objectives are to determine the molecular mechanism of the incision step of excision repair of ultraviolet (UV) light damaged DNA in eukaryotic organisms, using the yeast Saccharomyces cerevisiae as a model system, as well as studying the human homologs of yeast excision repair and postreplication repair proteins. In addition to its single-stranded DNA-dependent A TPase and DNA helicase activities, we have found that RAD3 protein also possesses DNA-RNA helicase activity, and that like RAD3, the Schizosaccharomyces pombe RAD3 homolog, rhp3{sup +}, is an essential gene. We have overexpressed the human RAD3 homolog, ERCC2, in yeast to facilitate its purification. The RAD10 protein was purified to homogeneity and shown to bind DNA. ERCC3y, the yeast homolog of the human ERCC-3/XP-B gene, has been sequenced and shown to be essential for viability. The Drosophila and human homologs of RAD6, required for postreplication repair and UV induced mutagenesis, were shown to complement the rad6 {Delta} mutation of yeast. Since defective DNA repair and enhanced neoplasia characterize several human genetic diseases, and repair proteins are highly conserved between yeast and man, a thorough understanding of the molecular mechanisms of DNA repir in yeast should provide a better understanding of the causes of carcinogenesis.

Prakash, L.

1991-04-01T23:59:59.000Z

80

International congress on DNA damage and repair: Book of abstracts  

SciTech Connect

This document contains the abstracts of 105 papers presented at the Congress. Topics covered include the Escherichia coli nucleotide excision repair system, DNA repair in malignant transformations, defective DNA repair, and gene regulation. (TEM)

Not Available

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

NSLS Services | Repair & Equipment Services  

NLE Websites -- All DOE Office Websites (Extended Search)

Repair & Equipment Services Repair & Equipment Services Cleaning Facility (BNL Central Shops) Solvent cleaning of vacuum parts and leak checking service is also available. Work is billed to each user via a BNL ILR. Contact the NSLS Building Manager to arrange for any of these services. Electronics Repair Limited repairs for electronic equipment are available from an outside contractor through the Control Room. Contact Control Room Supervisor Randy Church (x2550 or x2736, pager 5310). Shipping memos are filled out on the web, and pick ups are on Fridays. Come to the Control Room for assistance. The user should call the contractor on the day before scheduled pickups to alert the contractor of the pickup. Items to be repaired should be left in the Control Room with the completed shipping memo. Costs are charged to the

82

DNA repair in cells sensitive and resistant to cis-diamminedichloroplatinum(II): Host cell reactivation of damaged plasmid DNA  

SciTech Connect

cis-Diamminedichloroplatinum(II) (cis-DDP) has a broad clinical application as an effective anticancer drug. However, development of resistance to the cytotoxic effects is a limiting factor. In an attempt to understand the mechanism of resistance, the authors have employed a host cell reactivation assay of DNA repair using a cis-DDP-damaged plasmid vector. The efficiency of DNA repair was assayed by measuring the activity of an enzyme coded for by the plasmid vector. The plasmid expression vector pRSV cat contains the bacterial gene coding for chloramphenicol acetyltransferase (CAT) in a configuration which permits expression in mammalian cells. The plasmid was transfected into repair-proficient and -deficient Chinese hamster ovary cells, and CAT activity was subsequently measured in cell lysates. In the repair-deficient cells, one cis-DDP adduct per cat gene was sufficient to eliminate expression. An equivalent inhibition of CAT expression in the repair-proficient cells did not occur until about 8 times the amount of damage was introduced into the plasmid. These results implicate DNA intrastrand cross-links as the lesions responsible for the inhibition of CAT expression. This assay was used to investigate the potential role of DNA repair in mediating cis-DDP resistance in murine leukemia L1210 cells. The assay readily detects the presence or absence of repair and confirms that these resistant L1210 cells have an enhanced capacity for repair of cis-DDP-induced intrastrand cross-links.

Sheibani, N.; Jennerwein, M.M.; Eastman, A. (Univ. of Nebraska Medical Center, Omaha (USA))

1989-04-04T23:59:59.000Z

83

Common Air Conditioner Problems | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Common Air Conditioner Problems Common Air Conditioner Problems Common Air Conditioner Problems May 30, 2012 - 6:41pm Addthis A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. What does this mean for me? You can eliminate the most common air conditioner problems before hiring an air conditioning technician. You can do some air conditioner maintenance and repair tasks yourself. One of the most common air conditioning problems is improper operation. If your air conditioner is on, be sure to close your home's windows and outside doors. For room air conditioners, isolate the room or a group of connected rooms as much as possible from the rest of your home.

84

Common Air Conditioner Problems | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Common Air Conditioner Problems Common Air Conditioner Problems Common Air Conditioner Problems May 30, 2012 - 6:41pm Addthis A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. A refrigerant leak is one common air conditioning problem. | Photo courtesy of ©iStockphoto/BanksPhotos. What does this mean for me? You can eliminate the most common air conditioner problems before hiring an air conditioning technician. You can do some air conditioner maintenance and repair tasks yourself. One of the most common air conditioning problems is improper operation. If your air conditioner is on, be sure to close your home's windows and outside doors. For room air conditioners, isolate the room or a group of connected rooms as much as possible from the rest of your home.

85

Laser engineered net shaping (LENS) for the repair and modification of NWC metal components.  

DOE Green Energy (OSTI)

Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a layer additive manufacturing process that creates fully dense metal components using a laser, metal powder, and a computer solid model. This process has previously been utilized in research settings to create metal components and new material alloys. The ''Qualification of LENS for the Repair and Modification of Metal NWC Components'' project team has completed a Technology Investment project to investigate the use of LENS for repair of high rigor components. The team submitted components from four NWC sites for repair or modification using the LENS process. These components were then evaluated for their compatibility to high rigor weapons applications. The repairs included hole filling, replacement of weld lips, addition of step joints, and repair of surface flaws and gouges. The parts were evaluated for mechanical properties, corrosion resistance, weldability, and hydrogen compatibility. This document is a record of the LENS processing of each of these component types and includes process parameters, build strategies, and lessons learned. Through this project, the LENS process was shown to successfully repair or modify metal NWC components.

Atwood, Clinton J.; Smugeresky, John E. (Sandia National Labs, Livermore,CA); Gill, David Dennis

2006-11-01T23:59:59.000Z

86

A Newly Discovered DNA Repair Mechanism | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

scanning for these lesions. When they encounter one, they break the base pair bond and flip the deformed base out of the DNA double helix. The enzyme contains a specially shaped...

87

Mechanisms of initiation of DNA mismatch repair in Saccharomyces cerevisiae  

E-Print Network (OSTI)

increased mutation rates increase the rate of accumulationresult in mutation rate increases of up to several thousand-10 -5 (93) Mutation rate (fold increase) a Thr 4.2 [3.6-5.3

Shell, Scarlet Sara

2008-01-01T23:59:59.000Z

88

DART: a data acquisition and repairing tool  

Science Conference Proceedings (OSTI)

An architecture is proposed providing robust data acquisition facilities from input documents containing tabular data. This architecture is based on a data-repairing framework exploiting integrity constraints defined on the input data to support the ...

Bettina Fazzinga; Sergio Flesca; Filippo Furfaro; Francesco Parisi

2006-03-01T23:59:59.000Z

89

The technical and economic success of repairable PDC bits  

Science Conference Proceedings (OSTI)

Repairable PDC bits have saved operators and contractors millions of dollars in bit costs alone. The repair of steel-bodied PDC bits has been going on for over 4 years but more recently, due to technical innovations, matrix body bits are becoming repairable. DBS was concerned when starting the repairability project that the quality of a repaired bit be close to that of a new bit. Conventional thinking had it that the repaired bit would at best be slightly inferior to a new bit. However, during our initial evaluation of repaired steel-bodied bits, the authors noticed that, remarkably, the repaired bits overall drilled more footage per run at a higher rate of penetration than new bits. After over 200 bits had been run, repaired, and rerun, in every case and for every bit style the average footage and ROP were slightly higher for the repaired bit.

Matson, L.; Stratabit, D.B.

1989-03-01T23:59:59.000Z

90

Energy and Technology Review: Unlocking the mysteries of DNA repair  

SciTech Connect

DNA, the genetic blueprint, has the remarkable property of encoding its own repair following diverse types of structural damage induced by external agents or normal metabolism. We are studying the interplay of DNA damaging agents, repair genes, and their protein products to decipher the complex biochemical pathways that mediate such repair. Our research focuses on repair processes that correct DNA damage produced by chemical mutagens and radiation, both ionizing and ultraviolet. The most important type of DNA repair in human cells is called excision repair. This multistep process removes damaged or inappropriate pieces of DNA -- often as a string of 29 nucleotides containing the damage -- and replaces them with intact ones. We have isolated, cloned, and mapped several human repair genes associated with the nucleotide excision repair pathway and involved in the repair of DNA damage after exposure to ultraviolet light or mutagens in cooked food. We have shown that a defect in one of these repair genes, ERCC2, is responsible for the repair deficiency in one of the groups of patients with the recessive genetic disorder xeroderma pigmentosum (XP group D). We are exploring ways to purify sufficient quantities (milligrams) of the protein products of these and other repair genes so that we can understand their functions. Our long-term goals are to link defective repair proteins to human DNA repair disorders that predispose to cancer, and to produce DNA-repair-deficient mice that can serve as models for the human disorders.

Quirk, W.A.

1993-04-01T23:59:59.000Z

91

HANFORD SITE LOW EXPOSURE PIPELINE REPAIR USING A NON-METALLIC COMPOSITE SYSTEM  

Science Conference Proceedings (OSTI)

At the Department of Energy, Richland Operations (DOE-RL) Hanford site in eastern Washington, a 350 mm (14 inch) diameter high density polyethylene (HDPE) pump recirculation pipeline failed at a bonded joint adjacent to a radiologically and chemically contaminated groundwater storage basin. The responsible DOE-RL contractor, CH2MHill Plateau Remediation Company, applied a fiberglass reinforced plastic (composite) field repair system to the failed joint. The system was devised specifically for the HDPE pipe repair at the Hanford site, and had not been used on this type of plastic piping previously. This paper introduces the pipe failure scenario, describes the options considered for repair and discusses the ultimate resolution of the problem. The failed pipeline was successfully returned to service with minimal impact on waste water treatment plant operating capacity. Additionally, radiological and chemical exposures to facility personnel were maintained as low as reasonably achievable (ALARA). The repair is considered a success for the near term, and future monitoring will prove whether the repair can be considered for long term service and as a viable alternative for similar piping failures at the Hanford site.

HUTH RJ

2009-11-12T23:59:59.000Z

92

A sociotechnical framework for understanding infrastructure breakdown and repair  

SciTech Connect

This paper looks at how and why infrastructure is repaired. With a new era of infrastructure spending underway, policymakers need to understand and anticipate the particular technical and political challenges posed by infrastructure repair. In particular, as infrastructure problems are increasingly in the public eye with current economic stimulus efforts, the question has increasingly been asked: why has it been so difficult for the United Statesto devote sustained resources to maintaining and upgrading its national infrastructure? This paper provides a sociotechnical framework for understanding the challenges of infrastructure repair, and demonstrates this framework using a case study of seismic retrofit of freeway bridges in California. The design of infrastructure is quite different from other types of design work even when new infrastructure is being designed. Infrastructure projects are almost always situated within, and must work with, existing infrastructure networks. As a result, compared to design of more discrete technological artifacts, the design of infrastructure systems requires a great deal of attention to interfaces as well as adaptation of design to the constraints imposed by existing systems. Also, because of their scale, infrastructural technologies engage with social life at a level where explicit political agendas may playa central role in the design process. The design and building of infrastructure is therefore often an enormously complex feat of sociotechnical engineering, in which technical and political agendas are negotiated together until an outcome is reached that allows the project to move forward. These sociotechnical settlements often result in a complex balancing of powerful interests around infrastructural artifacts; at the same time, less powerful interests have historically often been excluded or marginalized from such settlements.

Sims, Benjamin H [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

93

HYDROGEN EFFECTS ON LASER ENGINEERED NET SHAPE (LENS) REPAIRED WELDMENTS  

DOE Green Energy (OSTI)

New methods of repairing mis-machined components are always of interest. In this study, an innovative method using Laser Engineered Net Shape{trademark} (LENS{reg_sign}) forming was used to repair intentionally mis-machined test articles. The components were repaired and subsequently hydrogen charged and burst tested. The LENS repair did not have an adverse effect on the solid state weld process that was used to repair the components. Hydrogen charged samples failed in a similar manner to the uncharged samples. Overall, the prospects for LENS repairing similar products are favorable and further work is encouraged.

Korinko, P; Thad Adams, T

2006-10-06T23:59:59.000Z

94

Valve Application, Maintenance, and Repair Guide  

Science Conference Proceedings (OSTI)

The Valve Application, Maintenance, and Repair Guide is a two-volume series that provides a generic overview of valve application, selection, maintenance, and repair. Volume 1 of the series is a comprehensive reference on the application and use of valves that provides guidance on the selection of specific types of valves on the basis of functional and system requirements. This document is based on an earlier EPRI document (NP-6516, Guide for the Application and Use of Valves in Power Plant Systems). Ext...

1999-05-07T23:59:59.000Z

95

Low Dose Radiation Research Program: Genetic Control of Repair and Adaptive  

NLE Websites -- All DOE Office Websites (Extended Search)

Repair and Adaptive Responses to Low-level DNA Damage Repair and Adaptive Responses to Low-level DNA Damage James E. Haber Brandeis University Why This Project In order to fully understand mechanisms resulting in effects of low dose, whole system rather than cells must be examined. Although not identical to mammalian systems, simple systems usually have many similarities and give direction for further study of more complex systems. We use the budding yeast, Saccharomyces cerevisiae, as a model system because it is easy to manipulate and its genome is simple and well characterized. Project Goals Examine mechanisms and effects of low dose radiation response for: Genetic recombination mechanisms that lead to genomic instability Genetic factors that affect individual susceptibility to low-dose radiation The adaptive response

96

Improved syntactic models for parsing speech with repairs  

Science Conference Proceedings (OSTI)

This paper introduces three new syntactic models for representing speech with repairs. These models are developed to test the intuition that the erroneous parts of speech repairs (reparanda) are not generated or recognized as such while occurring, but ...

Tim Miller

2009-05-01T23:59:59.000Z

97

Survey of Gas Turbine Component Repair Shops - 2008 Update  

Science Conference Proceedings (OSTI)

Aftermarket repair services for gas turbine O&M has been undergoing continual transformation beginning with the emergence of independent shops in the 1980s. The original equipment manufacturers (OEMs) began to aggressively pursue repair services in the late 1990s. Gas turbine hot section component repair/replacement coupled with inspection/overhaul technical support has come to be known broadly as long-term service agreements (LTSAs). These agreements often extend from 6 to 18 years. The repair business ...

2009-03-17T23:59:59.000Z

98

Welding and Repair Technology Center: Underwater Laser Welding Studies  

Science Conference Proceedings (OSTI)

Repair of internal reactor components has been a continuing challenge for the nuclear industry. High radiation levels, underwater environment, and altered material weldability have made traditional repair methods more difficult to use for internal component repair. One of the key issues is to make seal-weld repairs on cracks that might exist due to stress corrosion or fatigue. Sealing of these cracks by welding might be necessary to maintain pressure boundary or flow requirements. During this research pr...

2009-12-21T23:59:59.000Z

99

Test problems for quasi-satellite packing????  

E-Print Network (OSTI)

1. Test problems for quasi-satellite packing: Cylinders packing with behavior constraints and all the optimal solutions known. Chao Che. School of Mechanical  ...

100

STATISTICAL MECHANICS AND FIELD THEORY  

E-Print Network (OSTI)

1. L. 1. Schiff, Quantum Mechanics, third edition (McGraw-two-dimensional quantum mechanics problem vith a potential,Theory Methods to Statistical Mechanics Chapter I The Use of

Samuel, S.A.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Welding and Repair Technology Center: Welding and Repair Technical Issues in ASME Section XI  

Science Conference Proceedings (OSTI)

The EPRI Welding and Repair Technology Center (WRTC) supports and is involved in numerous ASME Code changes and new initiatives associated with welding, repair, and replacement activities in the nuclear power generation industry. Due to the complicated nature and numerous topics often associated with code and regulatory issues it can be difficult to keep abreast of the current status and progress of changes and new initiatives. This document is intended to be a single reference for WRTC members to ...

2012-12-20T23:59:59.000Z

102

Welding and Repair Technology Center: Welding and Repair Technical Issues in ASME Section XI  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute (EPRI) Welding and Repair Technology Center (WRTC) was involved in numerous ASME Code changes and new initiatives associated with welding, repair, and replacement activities in the nuclear power generation industry during the year 2013. Due to the complicated nature of code and regulatory issues and its variety of topics, it can be difficult to keep abreast of the current status, progress, and new initiatives. This report is intended to be a single reference for ...

2013-12-16T23:59:59.000Z

103

Manual of Bearing Failures and Repair in Power Plant Rotating Equipment  

Science Conference Proceedings (OSTI)

Turbine bearing failures in electric utilities can be responsible for outages resulting in significant lost generation time. In addition to bearing failures in the turbogenerators, failures may occur in other rotating equipment, such as pumps, fans, and auxiliary systems. Knowledge of bearing failure mechanisms and causes allows utilities to introduce safeguards into their occurrence and take faster remedial action. EPRI released the initial report, Manual of Bearing Failures and Repair in Power Plant Ro...

2011-12-15T23:59:59.000Z

104

Welding and Repair Technology Center: Overlay Handbook  

Science Conference Proceedings (OSTI)

The discovery of primary water stress corrosion cracking (PWSCC) in pressurized water reactor (PWR) vessel heads and components has led to the use of corrosion-resistant high-nickel welding alloys for repair and mitigation activities. To date, more than 30 PWR units have applied weld overlays to pressurizer welds with detected indications or have applied them as a mitigation method. Although the application of weld overlays appears to be a viable solution to managing this difficult issue, the utility ind...

2012-06-29T23:59:59.000Z

105

Welding and Repair Technology Center: Overlay Handbook  

Science Conference Proceedings (OSTI)

This report reflects the commitment of the Electric Power Research Institute (EPRI) to serving its members by developing practical tools and guidance in response to specific needs of the industry.BackgroundThe discovery of primary water stress corrosion cracking (PWSCC) in pressurized water reactor (PWR) vessel heads and components has led to the use of corrosion-resistant high-nickel welding alloys for repair and mitigation activities. To date, more than 30 ...

2013-11-25T23:59:59.000Z

106

Distribution System Audits, Leak Detection, and Repair: Kirtland Air Force Base Leak Detection and Repair Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Best Management Practice Best Management Practice Case Study #3 Distribution System Audits, Leak Detection, and Repair Kirtland Air Force Base - Leak Detection and Repair Program Overview Kirtland Air Force Base (AFB) performed an award winning leak detection and repair program in 2006. The results of the project are saving Kirtland AFB 179 million gallons each year, which is over 16% of the total water use at the base. Kirtland AFB is located on 52,000 acres, southeast and adjacent to Albuquerque, New Mexico. The area is a high altitude desert, only receiving about 8 inches of rain each year. Kirtland AFB draws water from an under- ground aquifer via seven production wells through- out the base. The base also has access to water from the City of Albuquerque. The underground water

107

Distribution System Audits, Leak Detection, and Repair: Kirtland Air Force Base Leak Detection and Repair Program  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Best Management Practice Best Management Practice Case Study #3 Distribution System Audits, Leak Detection, and Repair Kirtland Air Force Base - Leak Detection and Repair Program Overview Kirtland Air Force Base (AFB) performed an award winning leak detection and repair program in 2006. The results of the project are saving Kirtland AFB 179 million gallons each year, which is over 16% of the total water use at the base. Kirtland AFB is located on 52,000 acres, southeast and adjacent to Albuquerque, New Mexico. The area is a high altitude desert, only receiving about 8 inches of rain each year. Kirtland AFB draws water from an under- ground aquifer via seven production wells through- out the base. The base also has access to water from the City of Albuquerque. The underground water

108

Low Dose Radiation Research Program: Quantification of Repair of  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells Authors: David Schild,1 and Larry H. Thompson,2 Institutions: 1Life Sciences Division, Lawrence Berkeley National Laboratory; and 2BBR Program, Lawrence Livermore National Laboratory Double-strand breaks (DSBs) are the biochemical lesions of primary concern in radiation related health effects. Compelling evidence from rodent and chicken model systems indicates that homologous recombinational repair (HRR) plays an essential role for cell viability in the repair of spontaneous DSBs arising during DNA replication and an important role in the repair of IR-induced DSBs. IR-induced DSBs are also repaired by error-prone nonhomologous end joining (NHEJ). Using hTERT-immortalized

109

Combustion Turbine Repair Guidelines: General Electric MS6001 Model B  

Science Conference Proceedings (OSTI)

For more than a decade, EPRI has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy frame gas turbines. The guidelines in this v...

2009-12-09T23:59:59.000Z

110

Combustion Turbine Repair Guidelines: Siemens V94.3A  

Science Conference Proceedings (OSTI)

For more than a decade, EPRI has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy frame gas turbines. The guidelines in this volume address...

2009-03-06T23:59:59.000Z

111

cutting stock problem  

Science Conference Proceedings (OSTI)

NIST. cutting stock problem. (classic problem). Definition: Find the best arrangement of shapes on rectangles to minimize ...

2013-08-23T23:59:59.000Z

112

Guide for Determining Motor Repair versus Motor Replacement  

Science Conference Proceedings (OSTI)

The Motor Replacement/Refurbishment Guide (MRRG) was written to aid with the determination on whether to repair an existing motor or to purchase a replacement motor. This guideline provides the basic tools necessary to make a determination based upon, but not limited to, the extent of the repair scope and the cost of the repair. This guideline presents a process to be utilized by the station or corporate motor specialist to assess the motor repair scope both initial and revised. The data gathering proces...

2005-12-23T23:59:59.000Z

113

Lower power prices and high repair costs drive nuclear retirements ...  

U.S. Energy Information Administration (EIA)

However, concerns over the length of the review process and the high costs associated with steam generator repairs led SCE to retire both reactors.

114

Federal Facilities Maintenance, Repair Report Calls for Action  

SciTech Connect

This article is an overview of a recent report by the Federal Facilities Council on "Predicting Outcomes from Investments in Maintenance and Repair of Federal Facilities."

Bartlett, Rosemarie

2012-10-01T23:59:59.000Z

115

Low Dose Radiation Research Program: Quantification of Repair...  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells David Schild Lawrence Berkeley National Laboratory Berkeley, California Why this...

116

Inhibition of homologous recombination repair in irradiated tumor cells pretreated with Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin  

Science Conference Proceedings (OSTI)

In order to investigate the mechanism of radio-sensitization by an Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG), we studied repair of DNA double strand breaks (DSBs) in irradiated human cells pre-treated with 17-AAG. DSBs are thought to be the critical target for radiation-induced cell death. Two human tumor cell lines DU145 and SQ-5 which showed clear radio-sensitization by 17-AAG revealed a significant inhibition of DSB repair, while normal human cells which did not show radio-sensitization by the drug indicated no change in the DSB repair kinetics with 17-AAG. We further demonstrated that BRCA2 was a novel client protein for Hsp90, and 17-AAG caused the degradation of BRCA2 and in turn altered the behavior of Rad51, a critical protein for homologous recombination (HR) pathway of DSB repair. Our data demonstrate for the first time that 17-AAG inhibits the HR repair process and could provide a new therapeutic strategy to selectively result in higher tumor cell killing.

Noguchi, Miho [Graduate School of Science and Technology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Yu, Dong [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Hirayama, Ryoichi [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Ninomiya, Yasuharu [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Sekine, Emiko [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kubota, Nobuo [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Ando, Koichi [Graduate School of Science and Technology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Okayasu, Ryuichi [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)]. E-mail: rokayasu@nirs.go.jp

2006-12-22T23:59:59.000Z

117

Classifying aging genes into DNA repair or non-DNA repair-related categories  

Science Conference Proceedings (OSTI)

The elderly population in almost every country is growing faster than ever before. However, our knowledge about the aging process is still limited despite decades of studies on this topic. In this report, we focus on the gradual accumulation of DNA damage ... Keywords: DNA-repair, aging, classification, feature selection, random forest

Yaping Fang, Xinkun Wang, Elias K. Michaelis, Jianwen Fang

2013-07-01T23:59:59.000Z

118

Repair worlds: maintenance, repair, and ICT for development in rural Namibia  

Science Conference Proceedings (OSTI)

This paper explores the nature and centrality of maintenance and repair ('M&R') work in the extension and sustainability of ICT infrastructure in the global South. Drawing from pragmatist traditions in CSCW and the social sciences at large, we develop ... Keywords: ethnography, ictd, infrastructure, maintenance, theory

Steven J. Jackson; Alex Pompe; Gabriel Krieshok

2012-02-01T23:59:59.000Z

119

PNNL: Doing Business - Contracting Mechanisms  

NLE Websites -- All DOE Office Websites (Extended Search)

Contracting Mechanisms for Work with PNNL Does your small business need expert advice on a technical problem? Does your university research project require state-of-the-art...

120

Structural Repairs for Transmission Structures: Anchors, Poles, and Lattice Construction  

Science Conference Proceedings (OSTI)

This document provides a brief overview of repair methods for transmission line lattice and pole structures and provides guidance on the complex financial issue of how to determine whether a corrosion repair should be accounted for as capital or expense.   BackgroundAs the North American electrical transmission system ages, many issues have to be addressed to keep the system functioning. The high voltage ...

2012-12-12T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Security - Problem Solved?  

Science Conference Proceedings (OSTI)

There are plenty of security problems that have solutions. Yet, our security problems don't seem to be going away. What's wrong here?

John Viega

2005-06-01T23:59:59.000Z

122

Development of a composite repair system for reinforcing offshore risers  

E-Print Network (OSTI)

A research program was conducted to investigate the application of composite materials in repairing corroded offshore risers, leading to the development of an optimized repair using a hybrid carbon/E-glass system. The objective of this research program was to investigate the feasibility of extending onshore composite repair techniques to offshore risers by developing integrated analytical and experimental methods. The study considered loads typical for offshore risers including internal pressure, tension, and bending. To fulfill this objective efforts included a state of the art assessment of current composite repair technology, designing a carbon-based composite repair system optimized by numerical simulation with prototype testing, and providing guidelines for industry in repairing and reinforcing offshore risers using composite materials. Research efforts integrated numerical modeling, as well as full-scale testing that included four composite repair manufacturers to assess the current state of the art on pipe samples with simulated corrosion reinforced with composite materials. Analysis and testing were also performed on the optimized carbon/E-glass system. The results of this program demonstrated that composite materials are a viable means for repairing corroded offshore steel risers as adequate reinforcement ensures that the steel risers are not loaded beyond acceptable design limits. For corroded risers, the results demonstrated through analysis and full-scale testing efforts that properly designed composite repair systems can provide adequate structural reinforcement to ensure that excessive strains are not induced in the steel when subjected to internal pressure, axial tension, and bending design loads. This was verified experimentally using strain gages placed beneath the composite repair. This program is the first of its kind and is thought to contribute significantly to the future of offshore riser repairs. It is likely that the findings of this program will foster future investigations involving operators by integrating their insights regarding the need for composite repair based on emerging technology. One of the most significant contributions to the existing body of work is the use of limit analysis in developing design limits for the repair of steel pipes using composite materials.

Alexander, Christopher Richard

2007-12-01T23:59:59.000Z

123

Guidelines for the Repair of Nuclear Power Plant Safety-Related Motors (NCIG-12)  

Science Conference Proceedings (OSTI)

These guidelines, the twelfth in a series cosponsored by NCIG, provide utilities with information on the repair of all classes of safety-related electric motors. Use of this information will permit capable repair shops to repair motors under the extension of utility quality assurance programs or by dedication of a commercially repaired motor.

1990-04-24T23:59:59.000Z

124

Haier Repair Confusion Resolved | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

On January 7, 2010, DOE entered into a Consent Decree with Haier America regarding a problem with four models of Haier freezers that resulted in those freezers not achieving...

125

Assessment of airplane design, fabrication, and repair  

E-Print Network (OSTI)

Engineering programs are most often classes dedicated to how to design things, while the topic of reverse engineering or problem solving is rarely discussed. This unequal presentation of two sides of the same discipline ...

Stolar, Lauren (Lauren Elise)

2009-01-01T23:59:59.000Z

126

Welding and Repair Technology Center: Evaluation of High-Chromium Nickel-Base Welding Alloys, Resistance to Solidification Cracking - Update  

Science Conference Proceedings (OSTI)

One of the challenges faced by nuclear power industry engineers and managers responsible for making welding and repair decisions is selection of weld metals that have adequate resistance to stress corrosion cracking (SCC) with acceptable resistance to other forms of cracking. Continued testing and evaluation of new and enhanced high-chromium nickel-base filler metals is important to understanding the influence of slight composition changes on sensitivity to known cracking mechanisms and general ...

2013-08-14T23:59:59.000Z

127

Mechanical well jar  

Science Conference Proceedings (OSTI)

This patent describes a mechanical well jar having inner and outer tubular members movable longitudinally relative to each other a limited distance. Means for connecting one of the members to a pipe string extends above the jar. Means connect the other member to the pipe string below the jar. Annular shoulders on the members engage to limit the relative longitudinal movement of the members. The improvement comprises: laterally spaced, arcuate cam plates each attached to the inner surface of the outer member by threaded members that extend through the wall of the outer member and that can be removed from outside the outer member to allow the cam plates to be removed and repaired or replaced.

Burton, C.A.

1987-05-19T23:59:59.000Z

128

Optimizing chondrogenic factors and protein delivery methods for cartilage repair  

E-Print Network (OSTI)

Joint injuries are common and often result in damage to cartilage, which has a limited ability to repair itself. Tissue engineering is a promising approach for improving cartilage healing in which biomaterials and chemical ...

Florine, Emily Marie

2012-01-01T23:59:59.000Z

129

Competing risks for repairable systems: A data study  

E-Print Network (OSTI)

". The maintainable items making up the compressor unit are, among others, valves, internal piping and radial bearing by the corresponding repair. We will therefore follow the OREDA Handbook and make our analysis at the subunit level

Langseth, Helge

130

Solar Water Heating System Maintenance and Repair | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Water Heating System Maintenance and Repair Water Heating System Maintenance and Repair Solar Water Heating System Maintenance and Repair May 30, 2012 - 2:35pm Addthis Rooftop solar water heaters need regular maintenance to operate at peak efficiency. | Photo from iStockphoto.com Rooftop solar water heaters need regular maintenance to operate at peak efficiency. | Photo from iStockphoto.com Solar energy systems require periodic inspections and routine maintenance to keep them operating efficiently. Also, from time to time, components may need repair or replacement. You should also take steps to prevent scaling, corrosion, and freezing. You might be able to handle some of the inspections and maintenance tasks on your own, but others may require a qualified technician. Ask for a cost estimate in writing before having any work done. For some systems, it may

131

Gas Turbine Compressor Field Repair Guideline: GE 7FA  

Science Conference Proceedings (OSTI)

This guideline is designed to assist gas turbine owners confronted with limited damage to compressor rotating blade airfoils. The guideline addresses typical damage to the airfoil tip and leading edge where a limited amount of material trimming and blending is allowable. The guideline provides an engineering basis for implementing safe repairs and avoiding possible risk of airfoil failure due to high-cycle fatigue. In-situ field repair criteria are given for each compressor row R-0 through R-17 for ...

2012-12-03T23:59:59.000Z

132

On site ESP repair pays off in Indonesia  

Science Conference Proceedings (OSTI)

This paper discusses how extensive production and use of electric submersible pumps (ESPs) in a remote region of Southeast Asia prompted an oil company to establish its own ESP repair facility. The facility has met three defined objectives, and the scope of its work has been expanded. However, several elements must be present before such a remote operation can be successful. This repair facility is at the Kasim Marine Terminal in Irian Jaya.

Haines, J.D. (Southeast Asia Corp., Applied Technics, Skiatook, OK (US)); Langnes, G.L. (Dragon Pacific Offshore Services PTE, Ltd. (SG)); Hadipoetro, H. (Petromer Trend Corp., Kasmim Marine Terminal, Irian Jaya (ID))

1990-09-10T23:59:59.000Z

133

Steam Turbine Casing and Valve Body Repair Guidelines  

Science Conference Proceedings (OSTI)

Today’s flexible mode of operation can result in damage to heavy-section components, such as steam turbine and valve casings. Thus, owners and operators are often faced with repairing a critical component. This report is part of a set of documents that address the key areas in the asset management of steam turbine casings and valve bodies—nondestructive evaluation and damage detection, repair, and life ...

2013-12-14T23:59:59.000Z

134

Exposure Evaluation for Benzene, Lead and Noise in Vehicle and Equipment Repair Shops  

SciTech Connect

An exposure assessment was performed at the equipment and vehicle maintenance repair shops operating at the U. S. Department of Energy Hanford site, in Richland, Washington. The maintenance shops repair and maintain vehicles and equipment used in support of the Hanford cleanup mission. There are three general mechanic shops and one auto body repair shop. The mechanics work on heavy equipment used in construction, cranes, commercial motor vehicles, passenger-type vehicles in addition to air compressors, generators, and farm equipment. Services include part fabrication, installation of equipment, repair and maintenance work in the engine compartment, and tire and brake services. Work performed at the auto body shop includes painting and surface preparation which involves applying body filler and sanding. 8-hour time-weighted-average samples were collected for benzene and noise exposure and task-based samples were collected for lead dust work activities involving painted metal surfaces. Benzene samples were obtained using 3M™ 3520 sampling badges and were analyzed for additional volatile organic compounds. These compounds were selected based on material safety data sheet information for the aerosol products used by the mechanics for each day of sampling. The compounds included acetone, ethyl ether, toluene, xylene, VM&P naphtha, methyl ethyl ketone, and trichloroethylene. Laboratory data for benzene, VM&P naphtha, methyl ethyl ketone and trichloroethylene were all below the reporting detection limit. Airborne concentrations for acetone, ethyl ether, toluene and xylene were all less than 10% of their occupational exposure limit. The task-based samples obtained for lead dusts were submitted for a metal scan analysis to identify other metals that might be present. Laboratory results for lead dusts were all below the reporting detection limit and airborne concentration for the other metals observed in the samples were less than 10% of the occupational exposure limit. Noise dosimetry sampling was performed on a random basis and was representative of the different work activities within the four shops. Twenty three percent of the noise samples exceeded the occupational exposure limit of 85 decibels for an 8-hour time-weightedaverage. Work activities where noise levels were higher included use of impact wrenches and grinding wheels.

Sweeney, Lynn C.

2013-04-10T23:59:59.000Z

135

Estimation the Performance of Solar Fiber Optic Lighting System after Repairing the Glass Fiber Cables in a South Korean Residential Building  

E-Print Network (OSTI)

The solar fiber optic lighting system consists of the solar ray concentrating apparatus, the tracking control, lighting transmission and emission parts. This system was installed on a 20-storey apartment building in South Korea. Many residents had concerns about its long-term maintenance. The most common maintenance difficulties are sun tracking problems and damaged glass fiber cables. Sometimes fiber optic lighting systems should not be repaired with splices. Splicing glass fiber cables often results in decreased system efficiency and further cable damage. In this study, the cost of replacing the cables was prohibitive; hence, the drop in efficiency of the damaged cables was answered by repairing through splicing. These damaged cables were repaired by specially process of cutting and polishing. Results showed that the luminous intensity ratio improved by 0.391%, though this was still lower than the recommended guideline of 0.725%. Accordingly, on average 55% of luminous intensity was increased.

Cha, K. S.; Kim, T. K.; Park, M. S.

2009-11-01T23:59:59.000Z

136

Biochemical characterization of the E. coli Very Short Patch Repair pathway and its coordination with methyltransferase repair of 0?-methylguanine  

E-Print Network (OSTI)

The E. coli Very Short Patch Repair (VSPR) system corrects T:G mismatches that arise through Dcm-mediated methylation and subsequent deamination of the underlined cytosine residue in the palindromic sequence 5'-CCWGG-3' ...

Rye, Peter Thomas

2006-01-01T23:59:59.000Z

137

Symmetry in Scheduling Problems  

E-Print Network (OSTI)

Nov 16, 2010 ... 2 Problem Symmetry and Fundamental Domains ...... Handbook of Computational Group Theory (Discrete Mathematics and Its Applica- tions).

138

Bohmian Mechanics  

E-Print Network (OSTI)

Bohmian mechanics is a theory about point particles moving along trajectories. It has the property that in a world governed by Bohmian mechanics, observers see the same statistics for experimental results as predicted by quantum mechanics. Bohmian mechanics thus provides an explanation of quantum mechanics. Moreover, the Bohmian trajectories are defined in a non-conspiratorial way by a few simple laws.

Detlef Duerr; Sheldon Goldstein; Roderich Tumulka; Nino Zanghi

2009-03-15T23:59:59.000Z

139

Mechanical down jar mechanism  

SciTech Connect

This paper describes a mechanical down jar mechanism for freeing stuck objects within a well bore and for conducting other down hole activities. It comprises: an elongate tubular housing having anvil means; mandrel means adapted for connection to an object to be moved downwardly within the well bore and being disposed in telescoping relation with the anvil means and the elongate tubular housing, the mandrel means adapted to be struck by the anvil means to impart a downwardly directed jarring force to the object; the elongate tubular housing having internal firing and recocking detent groove means located in axially spaced relation and forming a firing lug support land therebetween; a radially expandable and retractable firing lug assembly being disposed within the elongate tubular housing and in absence of force being applied axially thereto being radially restrained by the firing lug support land; load spring means being disposed within the elongate tubular housing and being in downward force transmitting relation with the firing lug assembly; recocking spring means being disposed within the elongate tubular housing and having upward axial force transmitting relation with the firing lug assembly.

Taylor, W.T.

1991-12-03T23:59:59.000Z

140

LENS repair and modification of metal NW components:materials and applications guide.  

DOE Green Energy (OSTI)

Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a unique, layer additive, metal manufacturing technique that offers the ability to create fully dense metal features and components directly from a computer solid model. LENS offers opportunities to repair and modify components by adding features to existing geometry, refilling holes, repairing weld lips, and many other potential applications. The material deposited has good mechanical properties with strengths typically slightly higher that wrought material due to grain refinement from a quickly cooling weld pool. The result is a material with properties similar to cold worked material, but without the loss in ductility traditionally seen with such treatments. Furthermore, 304L LENS material exhibits good corrosion resistance and hydrogen compatibility. This report gives a background of the LENS process including materials analysis addressing the requirements of a number of different applications. Suggestions are given to aid both the product engineer and the process engineer in the successful utilization of LENS for their applications. The results of testing on interface strength, machinability, weldability, corrosion resistance, geometric effects, heat treatment, and repair strategy testing are all included. Finally, the qualification of the LENS process is briefly discussed to give the user confidence in selecting LENS as the process of choice for high rigor applications. The testing showed LENS components to have capability in repair/modification applications requiring complex castings (W80-3 D-Bottle bracket), thin wall parts requiring metal to be rebuilt onto the part (W87 Firing Set Housing and Y-12 Test Rings), the filling of counterbores for use in reservoir reclamation welding (SRNL hydrogen compatibility study) and the repair of surface defects on pressure vessels (SRNL gas bottle repair). The material is machinable, as testing has shown that LENS deposited material machines similar to that of welded metal. Tool wear is slightly higher in LENS material than in wrought material, but not so much that one would be concerned with increased tooling cost. The LENS process achieved process qualification for the AY1E0125 D-Bottle Bracket from the W80-3 LEP program, and in the effort, also underwent testing in weapons environments. These tests included structural dynamic response testing and drop testing. The LENS deposited parts were compared in these tests with conventionally machined parts and showed equivalency to such an extent that the parts were accepted for use in parallel path subsystem-level weapon environment testing. The evaluation of LENS has shown that the process can be a viable option when either complete metal parts are needed or existing metal parts require modification or repair. The LENS Qualification Technology Investment team successfully investigated new applications for the LENS process and showed that it has great applicability across the Nuclear Weapons Complex as well as in other high rigor applications.

Smugeresky, John E. (Sandia National Laboratories, Livermore, CA); Gill, David Dennis; Oberhaus, Jason (BWXT Y-12); Adams, Thad (Savannah River National Laboratory); VanCamp, Chad (Kansas City Plant)

2006-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Recombinant methods for screening human DNA excision repair proficiency  

SciTech Connect

A method for measuring DNA excision repair in response to ultraviolet radiation (UV)-induced DNA damage has been developed, validated, and field-tested in cultured human lymphocytes. The methodology is amenable to population-based screening and should facilitate future epidemiologic studies seeking to investigate associations between excision repair proficiency and cancer susceptibility. The impetus for such endeavors derives from the belief that the high incidence of skin cancer in the genetic disorder xeroderma pigmentosum (XP) primarily is a result of the reduced capacity of patients cells to repair UV-induced DNA damage. For assay, UV-irradiated non-replicating recombinant plasmid DNA harboring a chloramphenicol acetyltransferase (CAT) indicator gene is introduced into lymphocytes using DEAE-dextran short-term transfection conditions. Exposure to UV induces transcriptionally-inactivating DNA photoproducts in the plasmid DNA which inactivate CAT gene expression. Excision repair of the damaged CAT gene is monitored indirectly as a function of reactivated CAT enzyme activity following a 40 hour repair/expression incubation period.

Athas, W.F.

1988-01-01T23:59:59.000Z

142

Quantum Mechanics Without Observers  

E-Print Network (OSTI)

The measurement problem and the role of observers have plagued quantum mechanics since its conception. Attempts to resolve these have introduced anthropomorphic or non-realist notions into physics. A shift of perspective based upon process theory and utilizing methods from combinatorial games, interpolation theory and complex systems theory results in a novel realist version of quantum mechanics incorporating quasi-local, nondeterministic hidden variables that are compatible with the no-hidden variable theorems and relativistic invariance, and reproduce the standard results of quantum mechanics to a high degree of accuracy without invoking observers.

W. H. Sulis

2013-02-18T23:59:59.000Z

143

Troubleshoot HRSG corrosion problems  

SciTech Connect

Heat-recovery steam generators (HRSGs) have come of age. At the same time, these boilers are more complex as designs are refined to maximize heat recovery. Hundreds of units are installed and now have years of operating experience providing valuable information that can benefit all HRSG owners. Experienced troubleshooters can anticipate potential problem areas and recommend cost-effective solutions. The HRSG corrosion problems summarized here--and the means by which they were identified and solved--are useful examples to alert other HRSG owners and operators to potential problem areas. Steps involved include thorough inspection and documentation, problem and cost/benefit analyses, and planning around outages.

Stanley, L.

1996-07-01T23:59:59.000Z

144

Drinking Water Problems: Copper  

E-Print Network (OSTI)

High levels of copper in drinking water can cause health problems. This publication explains the effects of copper in water and methods of removing it. 4 pp.

Dozier, Monty; McFarland, Mark L.; Lesikar, Bruce J.

2006-01-25T23:59:59.000Z

145

The Interpretation of Quantum Mechanics  

E-Print Network (OSTI)

In this paper, we demonstrate how the interpretation of quantum mechanics due to Land\\'e resolves the Schr\\"odinger cat paradox and disposes of the problem of wave function collapse.

H. V. Mweene

2004-11-09T23:59:59.000Z

146

Involvement of DNA polymerase beta in repairing oxidative damages induced by antitumor drug adriamycin  

SciTech Connect

Adriamycin (ADM) is a widely used antineoplastic drug. However, the increasing cellular resistance has become a serious limitation to ADM clinical application. The most important mechanism related to ADM-induced cell death is oxidative DNA damage mediated by reactive oxygen species (ROS). Base excision repair (BER) is a major pathway in the repair of DNA single strand break (SSB) and oxidized base. In this study, we firstly applied the murine embryo fibroblasts wild-type (pol {beta} +/+) and homozygous pol {beta} null cell (pol {beta} -/-) as a model to investigate ADM DNA-damaging effects and the molecular basis underlying these effects. Here, cellular sensitivity to ADM was examined using colorimetric assay and colony forming assay. ADM-induced cellular ROS level and the alteration of superoxide dismutase (SOD) activity were measured by commercial kits. Further, DNA strand break, chromosomal damage and gene mutation were assessed by comet assay, micronucleus test and hprt gene mutation assay, respectively. The results showed that pol {beta} -/- cells were more sensitive to ADM compared with pol {beta} +/+ cells and more severe SSB and chromosomal damage as well as higher hprt gene mutation frequency were observed in pol {beta} -/- cells. ROS level in pol {beta} -/- cells increased along with decreased activity of SOD. These results demonstrated that pol {beta} deficiency could enable ROS accumulation with SOD activity decrease, further elevate oxidative DNA damage, and subsequently result in SSB, chromosome cleavage as well as gene mutation, which may be partly responsible for the cytotoxicity of ADM and the hypersensitivity of pol {beta} -/- cells to ADM. These findings suggested that pol {beta} is vital for repairing oxidative damage induced by ADM.

Liu Shukun; Wu Mei [Department of Environmental Health, Sichuan University, West China School of Public Health, Chengdu (China); Zhang Zunzhen, E-mail: zhangzunzhen@163.co [Department of Environmental Health, Sichuan University, West China School of Public Health, Chengdu (China)

2010-08-01T23:59:59.000Z

147

RECORD OF CATEGORICAL EXCLUSION DETERMINATION Hygiene Substation Access Road Repairs  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Hygiene Substation Access Road Repairs Hygiene Substation Access Road Repairs A. Brief Description of Proposal: Western Area Power Administration proposes to repair the access road/driveway into the Hygiene Substation. There is a low spot in the middle of the driveway that impedes maneuvering oflarge maintenance equipment in and out of the yard. Western plans to fill the low spot with road base and crumbled concrete fill. The Hygiene Substation is located in Boulder County, approximately 2 miles northwest of Longmont, CO (T3N, R69W, Sec 18). All proposed construction will occur within the existing, disturbed substation access road/driveway. B. Number and Title of tile Categorical Exclusion Being Applied: (See text in 10 CFR 1021, Subpart D.) BI.3 Routine maintenance activities and custodial services for buildings, structures,

148

Simple Maintenance Saves Costly Furnace Repair/Replacement | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Simple Maintenance Saves Costly Furnace Repair/Replacement Simple Maintenance Saves Costly Furnace Repair/Replacement Simple Maintenance Saves Costly Furnace Repair/Replacement January 6, 2010 - 8:26am Addthis Chris Stewart Senior Communicator at DOE's National Renewable Energy Laboratory For the past few weeks, my forced-air gas furnace has been on the fritz. I blame this on the fact that I haven't been as diligent as I should have been with regular furnace maintenance, which includes: Checking the condition of the vent connection pipe and chimney Checking the physical integrity of the heat exchanger Adjusting the controls to provide optimum water and air temperature settings for both efficiency and comfort Having a technician perform a combustion-efficiency test Checking the combustion chamber for cracks. Testing for carbon monoxide

149

ITOUGH2 sample problems  

DOE Green Energy (OSTI)

This report contains a collection of ITOUGH2 sample problems. It complements the ITOUGH2 User`s Guide [Finsterle, 1997a], and the ITOUGH2 Command Reference [Finsterle, 1997b]. ITOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media [Preuss, 1987, 1991a]. The report ITOUGH2 User`s Guide [Finsterle, 1997a] describes the inverse modeling framework and provides the theoretical background. The report ITOUGH2 Command Reference [Finsterle, 1997b] contains the syntax of all ITOUGH2 commands. This report describes a variety of sample problems solved by ITOUGH2. Table 1.1 contains a short description of the seven sample problems discussed in this report. The TOUGH2 equation-of-state (EOS) module that needs to be linked to ITOUGH2 is also indicated. Each sample problem focuses on a few selected issues shown in Table 1.2. ITOUGH2 input features and the usage of program options are described. Furthermore, interpretations of selected inverse modeling results are given. Problem 1 is a multipart tutorial, describing basic ITOUGH2 input files for the main ITOUGH2 application modes; no interpretation of results is given. Problem 2 focuses on non-uniqueness, residual analysis, and correlation structure. Problem 3 illustrates a variety of parameter and observation types, and describes parameter selection strategies. Problem 4 compares the performance of minimization algorithms and discusses model identification. Problem 5 explains how to set up a combined inversion of steady-state and transient data. Problem 6 provides a detailed residual and error analysis. Finally, Problem 7 illustrates how the estimation of model-related parameters may help compensate for errors in that model.

Finsterle, S.

1997-11-01T23:59:59.000Z

150

Welding and Repair Technology Center: Alternative Rules for Temperbead Qualification  

Science Conference Proceedings (OSTI)

Temperbead welding is common practice in the nuclear power industry for in situ repair of quenched and tempered low-alloy steels when post-weld heat treatment is impractical. The temperbead process controls the heat input so that the weld heat-affected zone in the low-alloy steel is tempered by the welding heat of subsequent layers. The tempering achieved in this way eliminates the need for post-weld heat treatment. Unfortunately, repair organizations in the nuclear power industry are ...

2012-09-28T23:59:59.000Z

151

Final Report for DOE Grant DE-FG02-03ER25579; Development of High-Order Accurate Interface Tracking Algorithms and Improved Constitutive Models for Problems in Continuum Mechanics with Applications to Jetting  

Science Conference Proceedings (OSTI)

Much of the work conducted under the auspices of DE-FG02-03ER25579 was characterized by an exceptionally close collaboration with researchers at the Lawrence Berkeley National Laboratory (LBNL). For example, Andy Nonaka, one of Professor Miller's graduate students in the Department of Applied Science at U. C. Davis (UCD) wrote his PhD thesis in an area of interest to researchers in the Applied Numerical Algorithms Group (ANAG), which is a part of the National Energy Research Supercomputer Center (NERSC) at LBNL. Dr. Nonaka collaborated closely with these researchers and subsequently published the results of this collaboration jointly with them, one article in a peer reviewed journal article and one paper in the proceedings of a conference. Dr. Nonaka is now a research scientist in the Center for Computational Sciences and Engineering (CCSE), which is also part of the National Energy Research Supercomputer Center (NERSC) at LBNL. This collaboration with researchers at LBNL also included having one of Professor Puckett's graduate students in the Graduate Group in Applied Mathematics (GGAM) at UCD, Sarah Williams, spend the summer working with Dr. Ann Almgren, who is a staff scientist in CCSE. As a result of this visit Sarah decided work on a problem suggested by the head of CCSE, Dr. John Bell, for her PhD thesis. Having finished all of the coursework and examinations required for a PhD, Sarah stayed at LBNL to work on her thesis under the guidance of Dr. Bell. Sarah finished her PhD thesis in June of 2007. Writing a PhD thesis while working at one of the University of California (UC) managed DOE laboratories is long established tradition at UC and Professor Puckett has always encouraged his students to consider doing this. Another one of Professor Puckett's graduate students in the GGAM at UCD, Christopher Algieri, was partially supported with funds from DE-FG02-03ER25579 while he wrote his MS thesis in which he analyzed and extended work originally published by Dr. Phillip Colella, the head of ANAG, and some of his colleagues. Chris Algieri is now employed as a staff member in Dr. Bill Collins' Climate Science Department in the Earth Sciences Division at LBNL working with computational models of climate change. Finally, it should be noted that the work conducted by Professor Puckett and his students Sarah Williams and Chris Algieri and described in this final report for DOE grant # DE-FC02-03ER25579 is closely related to work performed by Professor Puckett and his students under the auspices of Professor Puckett's DOE SciDAC grant DE-FC02-01ER25473 An Algorithmic and Software Framework for Applied Partial Differential Equations: A DOE SciDAC Integrated Software Infrastructure Center (ISIC). Dr. Colella was the lead PI for this SciDAC grant, which was comprised of several research groups from DOE national laboratories and five university PI's from five different universities. In theory Professor Puckett tried to use funds from the SciDAC grant to support work directly involved in implementing algorithms developed by members of his research group at UCD as software that might be of use to Puckett's SciDAC CoPIs. (For example, see the work reported in Section 2.2.2 of this final report.) However, since there is considerable lead time spent developing such algorithms before they are ready to become `software' and research plans and goals change as the research progresses, Professor Puckett supported each member of his research group partially with funds from the SciDAC APDEC ISIC DE-FC02-01ER25473 and partially with funds from this DOE MICS grant DE-FC02-03ER25579. This has necessarily resulted in a significant overlap of project areas that were funded by both grants. In particular, both Sarah Williams and Chris Algieri were supported partially with funds from grant # DE-FG02-03ER25579, for which this is the final report, and in part with funds from Professor Puckett's DOE SciDAC grant # DE-FC02-01ER25473. For example, Sarah Williams received support from DE-FC02- 01ER25473 and DE-FC02-03ER25579, both while at UCD taking cla

Puckett, Elbridge Gerry [U.C. Davis, Department of Mathematics; Miller, Gregory Hale [.C. Davis, Department of Chemical Engineering

2012-10-14T23:59:59.000Z

152

Bohmian mechanics contradicts quantum mechanics  

E-Print Network (OSTI)

Bohmian mechanics contradicts quantum mechanics Arnold Neumaier Institut fur Mathematik, Universit://solon.cma.univie.ac.at/#24;neum/ Abstract. It is shown that, for a harmonic oscillator in the ground state, Bohmian mechanics and quantum mechanics predict values of opposite sign for certain time correlations. The discrepancy can

Neumaier, Arnold

153

SOLERAS - Analysis of photovoltaic concentrator module failures and repair methods  

Science Conference Proceedings (OSTI)

This report presents the results of the failure analysis, performed from early 1984 through September 1986 on the open-circuited modules, and the assessment of repairing these modules on site at the Solar Village. 16 refs., 26 figs., 19 tabs.

Huraib, F.S.; Imamura, M.S.; Salim, A.A.; Rao, N.R.

1987-06-01T23:59:59.000Z

154

Proceedings: Welding and Repair Technology for Power Plants: Second International Conference  

Science Conference Proceedings (OSTI)

The conference on welding and repair technology for power plants included presentations of case histories, emerging welding technologies, and demonstrated repair techniques and approaches. These proceedings provide technical information discussed at the conference on the repair of turbine rotors, disks, blades, piping, steam generators, headers, reactor pressure vessel internals, valves, pumps, and other components.

1997-04-04T23:59:59.000Z

155

Technical Repair Guidelines for Limitorque Gear Operator Models HBC 0-10  

Science Conference Proceedings (OSTI)

This technical repair guide (TRG) for Limitorque gear operator models HBC-0 through HBC-10 is the fourth in a series of documents devoted to the comprehensive maintenance and repair of Limitorque valve actuators. This guide provides instructions for engineering, operations, and maintenance personnel on the repair, maintenance, and operation of Limitorque HBC gear operators and their accessories.

1993-10-02T23:59:59.000Z

156

Description of Past Research: Fossil Materials and Repair (Program 87): 2012 Update  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute’s (EPRI’s) Fossil Materials and Repair Program (Program 87) within Major Component Reliability provides integrated materials selection guidance, information about repair technology, and corrosion mitigation methods to improve equipment performance, reliability, and profitability. The program has produced numerous material and repair guidelines and handbooks for application with steam boilers, steam ...

2013-04-12T23:59:59.000Z

157

Technical Repair Guidelines for Limitorque Models SMB 0 Through 4 Valve Actuators  

Science Conference Proceedings (OSTI)

This technical repair guide for Limitorque motor-operated valve (MOV) actuator models SMB 0 through 4 represents the third in a series of documents devoted to the comprehensive maintenance and repair of Limitorque actuators. This guide provides instructions for engineering, operations, and maintenance personnel on MOV actuator repair, maintenance, adjustment, and troubleshooting methods.

1993-02-28T23:59:59.000Z

158

Welding and Repair Technology for Power Plants: Fourth RRAC International Conference  

Science Conference Proceedings (OSTI)

The Fourth International Conference on Welding and Repair Technology for Power Plants included presentations of case histories and emerging welding technologies and demonstrations of repair techniques and approaches. These proceedings provide technical information discussed during this conference regarding the repair of steam turbine rotors, discs, blades, piping, steam generators, headers, reactor pressure vessel internals, valves, pumps, combustion turbines, and other components. Sessions included nucl...

2000-09-30T23:59:59.000Z

159

Corrosion Problems and Solutions  

Science Conference Proceedings (OSTI)

Table 5   Typical deaerator corrosion problems...General corrosion of vessels and piping GC Layup, CH V, high iron in feedwater None N/A (a) CF, corrosion fatigue;

160

Swaging Problems and Solutions  

Science Conference Proceedings (OSTI)

Table 5   Some swaging problems, potential causes, and possible solutions...causes Solutions Difficult feeding Work material too hard Anneal or stress relieve to remove effects of cold

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

The Magnetotelluric Inverse Problem  

E-Print Network (OSTI)

1572–1592. Banks, R. , 1969: Geomagnetic variations and theThe inverse problem in geomagnetic induction. Z. Geophys. ,sound inferences from geomagnetic sounding, doi:10.1016/j.

Medin, Ashley E

2008-01-01T23:59:59.000Z

162

The magnetotelluric inverse problem  

E-Print Network (OSTI)

1572–1592. Banks, R. , 1969: Geomagnetic variations and theThe inverse problem in geomagnetic induction. Z. Geophys. ,sound inferences from geomagnetic sounding, doi:10.1016/j.

Medin, Ashley E.

2008-01-01T23:59:59.000Z

163

Hydrostatic Adjustment: Lamb's Problem  

Science Conference Proceedings (OSTI)

The prototype problem of hydrostatic adjustment for large-scale atmospheric motions is Presented. When a horizontally infinite layer of compressible fluid, initially at rest, is instantaneously heated, the fluid is no longer in hydrostatic ...

Peter R. Bannon

1995-05-01T23:59:59.000Z

164

Valve Application, Maintenance, and Repair Guide: In Situ State-of-the-Art Valve Welding Repair (Gate, Globe, & Check Valves), Volum e 2  

Science Conference Proceedings (OSTI)

The Valve Application, Maintenance and Repair Guide is a three volume series that provides a generic overview of valve application selection, maintenance, and repair. Volume 2 of this series is a comprehensive guide for in situ weld repair of gate, globe, and check valve components such as bodies, bonnets, discs, and seats. The information in this guide, though directed toward nuclear plant personnel, will assist all power plant engineers, planners, and maintenance personnel responsible for valve mainten...

1996-12-31T23:59:59.000Z

165

The Quantum-mechanical Many Body Problem: The Bose Gas  

E-Print Network (OSTI)

This article gives a detailed presentation of the authors' recent results on the ground state properties of the Bose gas. It is a much expanded version of a talk given by one of the authors (E.H.L.) at the conference "Perspectives in Analysis" at the KTH, Stockholm, June 23, 2003. It is based on, but supersedes, the article math-ph/0204027.

Elliott H. Lieb; Robert Seiringer; Jan Philip Solovej; Jakob Yngvason

2004-05-03T23:59:59.000Z

166

A tribological and biomimetic study of potential bone joint repair materials  

E-Print Network (OSTI)

This research investigates materials for bone-joint failure repair using tribological and biomimicking approaches. The materials investigated represent three different repairing strategies. Refractory metals with and without treatment are candidates for total joint replacements due to their mechanical strength, high corrosion resistance and biocompatibility. A composite of biodegradable polytrimethylene carbonate, hydroxyl apatite, and nanotubes was investigated for application as a tissue engineering scaffold. Non-biodegradable polymer polyimide combined with various concentrations of nanotubes was investigated as a cartilage replacement material. A series of experimental approaches were used in this research. These include analysis of material surfaces and debris using high-resolution techniques and tribological experiments, as well as evaluation of nanomechanical properties. Specifically, the surface structure and wear mechanisms were investigated using a scanning electron microscope and an atomic force microscope. Debris morphology and structure was investigated using a transmission electron microscope. The debris composition was analyzed using an X-ray diffractometer. Nanoindentation was incorporated to investigate the surface nanomechanical properties. Polytrimythelene carbonate combined with hydroxyapatite and nanotubes exhibited a friction coefficient lower than UHMWPE. The nanoindentation response mimicked cartilage more closely than UHMWPE. A composite formed with PI and nanotubes showed a varying friction coefficient and varying nanoindentation response with variation in nanotube concentration. Low friction coefficients corresponded with low modulus values. A theory was proposed to explain this behavior based on surface interactions between nanotubes and between nanotubes and PI. A model was developed to simulate the modulus as a function of nanotube concentration. The boronized refractory metals exhibited brittleness and cracking. Higher friction coefficients were associated with the formation of amorphous debris. The friction coefficient for boronized Cr (~0.06) under simulated body fluid conditions was in the range found in natural joints.

Ribeiro, Rahul

2006-12-01T23:59:59.000Z

167

Supercomputers Tackle Biofuel Production Problems  

NLE Websites -- All DOE Office Websites (Extended Search)

V V E R C O M I N G P L A N T R E C A L C I T R A N C E Supercomputers Tackle BIOFUEL Production Problems If you have ever dealt with an uncooperative, fractious kid or a combative employee, you understand the meaning of "recalcitrance" - over-the-top stubbornness, disobedience, and noncompliance. But recalcitrance is not just a human trait - plants can be recalcitrant, too, and for them it is a matter of survival. Over millions of years, plants have evolved complex structural and chemical mechanisms to ward off assaults on their structural sugars by microbial and animal marauders. So it should be no surprise that when humans attempt to turn plant biomass into biofuels to meet our energy needs, we discover how stubborn and noncompliant our vegetative friends can be. Plant recalcitrance is one of

168

The Sedov Test Problem  

SciTech Connect

The Sedov test is classically defined as a point blast problem. The Sedov problem has led us to advances in algorithms and in their understanding. Vorticity generation can be physical or numerical. Both play a role in Sedov calculations. The RAGE code (Eulerian) resolves the shock well, but produces vorticity. The source definition matters. For the FLAG code (Lagrange), CCH is superior to SGH by avoiding spurious vorticity generation. FLAG SGH currently has a number of options that improve results over traditional settings. Vorticity production, not shock capture, has driven the Sedov work. We are pursuing treatments with respect to the hydro discretization as well as to artificial viscosity.

Fung, Jimmy [Los Alamos National Laboratory; Masser, Thomas [Los Alamos National Laboratory; Morgan, Nathaniel R. [Los Alamos National Laboratory

2012-06-25T23:59:59.000Z

169

Problems associated with the establishment of a whole body counter at a university reactor  

E-Print Network (OSTI)

A widd variety of difficulties can arise in bringing a ics. whole body counting chair into operation for screening radiation workers. Problems can arise in the mechanical operation of the chair, in fabrication of phantom source bottles, and in calibrating the detectors. This project addressed all of these factors. Applied Physical Technology, Inc was once a manufacturer of whole body counting chairs. One of the chairs, Model WBC-6000 with three associated NaI(T1) detectors, was donated to Texas A&M University. In order to bring it into operation, physical repairs to the control box and emergency release mechanism were completed. The block phantom that accompanied the chair did not have source bottles. After establishing a set of procedures, several sets of source bottles were fabricated for use in the lung, Gl tract, and thyroid regions of the phantoms. With the radionuclide sources created, the equipment was assembled and a series of counts was performed in various source configurations. From the information collected in the counts, all three of the detectors were calibrated according to the guidelines established in ANSI N 13.30 and NCRP Report 57, using guidance from NUREG 8.9. The primary results of this project were: 1) a knowledge of how to establish procedures for generating radionuclides and manipulating the activities for use as a phantom source; 2) an intimate knowledge of gamma spectroscopy, including the creation of calibration efficiencies; and 3) a calibrated whole body counting system capable of confidently measuring internal radioactive contamination in personnel.

Fairchild, Gregory R

1999-01-01T23:59:59.000Z

170

Problems in medicine: hypercalcemia  

SciTech Connect

The pathophysiologic mechanisms for hypercalcemia are reviewed and a diagnostic approach to determining the cause of hypercalcemia in clinical cases in dogs and cats is recommended. 5 refs., 1 fig., 1 tab. (ACR)

Weller, R.E.

1985-06-01T23:59:59.000Z

171

Solving quantified constraint satisfaction problems  

Science Conference Proceedings (OSTI)

We make a number of contributions to the study of the Quantified Constraint Satisfaction Problem (QCSP). The QCSP is an extension of the constraint satisfaction problem that can be used to model combinatorial problems containing contingency or uncertainty. ... Keywords: Arc consistency, Quantified Boolean formulas, Quantified constraint satisfaction problems, Random problems, Search algorithms

Ian P. Gent; Peter Nightingale; Andrew Rowley; Kostas Stergiou

2008-04-01T23:59:59.000Z

172

Drinking Water Problems: Radionuclides  

E-Print Network (OSTI)

Radionuclides in drinking water can cause serious health problems for people. This publication explains what the sources of radionuclides in water are, where high levels have been found in Texas, how they affect health and how to treat water to remove them.

Lesikar, Bruce J.; Melton, Rebecca; Hare, Michael; Hopkins, Janie; Dozier, Monty

2006-08-04T23:59:59.000Z

173

Solar Cells, Wound Repair Winning GVC Technologies | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

Solar Cells, Wound Repair Winning GVC Technologies Solar Cells, Wound Repair Winning GVC Technologies March 26, 2010 Graduate student teams from the University of Arkansas and the University of Maryland earned first place in the energy and security categories at the 2010 GVC hosted by ORNL March 24-26. The competition, in its fourth year, attracts students developing new technologies and venture investors with expertise in the market. The first-prize winners each received $25,000. Douglas Hutchings, Stephen Ritterbush, and Seth Shumate from Arkansas won first place in the energy division for Silicon Solar Solutions. "Our method replaces the expensive top layer of solar cells with a thinner, large-grain polysilicon at lower temperatures, which reduces cost and is appealing to manufacturers," said Ritterbush.

174

The Molecular Mechanism of Stretch Activation in Insect Muscle | Advanced  

NLE Websites -- All DOE Office Websites (Extended Search)

A Newly Discovered DNA Repair Mechanism A Newly Discovered DNA Repair Mechanism Assessing the Risk of Arsenic Ingestion An Electronic Dance of Spins and Orbits How a Virus Prepares to Infect Cells Magnetic Switching under Pressure Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed The Molecular Mechanism of Stretch Activation in Insect Muscle DECEMBER 21, 2010 Bookmark and Share Main image: X-ray pattern from contracting flight muscle; top: match-mismatch of crossbridge origins with actin target zones; bottom: thick filament twisting bring myosin crossbridges closer to actin binding sites ("target zones"). Pink = target zones; red = myosin heads. Intruder at bottom: Lethocerus indicus.

175

Repair and Replacement Applications Center Joint Welding Procedure Qualification Program  

Science Conference Proceedings (OSTI)

At the request of the EPRI Repair and Replacement Applications Center subscribers, a Joint Welding Procedure Qualification Program was developed to provide a medium whereby multiple utilities can share in the qualification of specific welding procedures. The program was developed in such a manner that it will supplement existing utility welding qualification programs. Specifically the program incorporates the more stringent attributes of each utility's internal welding program while meeting the individua...

1997-11-12T23:59:59.000Z

176

Development of Methods to Repair Header Stub Tube Bends  

Science Conference Proceedings (OSTI)

Repair of flow-accelerated corrosion damage in bent header stub tubes in heat recovery steam generators (HRSGs) is normally accomplished by spreading tubing pendants to gain access, cutting your way in and welding your way out, or plugging damaged tubing. The technology described in this report is being developed to enable the replacement of damaged tubing in a method that will dramatically reduce change-out time in the event of a failure.

2008-12-23T23:59:59.000Z

177

HRSG Repair Welding Technologies to Address FAC in Tube Bends  

Science Conference Proceedings (OSTI)

Tube failures that occur in heat recovery steam generators (HRSGs) are often caused by thermal stress or thermal shock associated with cyclic plant operation or by flow-accelerated corrosion. Many premature failures occur along the length of finned tubes or at attachment locations where tubes are joined to the upper or lower header. Because of current tube repair practices and limited access for welding, reoccurring failures are common.

2008-03-20T23:59:59.000Z

178

Repair Welding Technologies For Heat Recovery Steam Generators  

Science Conference Proceedings (OSTI)

Tube failures that occur in heat recovery steam generators (HRSGs) are often caused by thermal stress or thermal shock associated with cyclic plant operation or by flow-accelerated corrosion. Many premature failures occur along the length of finned tubes or at attachment locations where tubes are joined to the upper or lower header. Because of current tube repair practices and limited access for welding, reoccurring failures are common.

2005-12-21T23:59:59.000Z

179

In Situ Temporary Repair of Thermal Barrier Coatings  

Science Conference Proceedings (OSTI)

The durability of thermal barrier coatings (TBCs) on combustion turbine blades and vanes is a critical issue in the power generation industry. Degradation of TBCs occur by the spallation of the ceramic layer — partially stabilized zirconia (PSZ) — that resides on the Al2O3-covered MCrAlY bondcoat. In the event of such local failures of the TBC, a quick in-situ technique to repair the coating would be desirable.

2005-03-31T23:59:59.000Z

180

Performance and Impact from Duct Repair and Ventilation Modifications of Two Newly Constructed Manufactured Houses Located in a Hot and Humid Climate  

E-Print Network (OSTI)

Two nearly identical houses situated next to each other in Bossier City, Louisiana were studied in an effort to better understand moisture and cooling energy related problems in manufactured houses with low thermostat set-points during the cooling season. By design, the major difference between houses was the type of air conditioning units. House A had a standard split air conditioner and House B had a twospeed split air conditioner. In an effort to make the buildings more similar, the building airtightness was adjusted until it was the same in each house, and duct leaks were sealed so that the ducts were tight and there was equal tightness in both houses. A ventilation system was also added at the same time of duct repair. Duct repair and the ventilation modifications resulted in significant impacts on the cooling energy, temperature, relative humidity, and building pressures. Cooling energy decreased 37% in House A and 18% in House B, while the floor space dewpoint increased significantly. It is estimated that 35 % savings was due solely to duct repair in House A and 17% in House B. The primary cause of House A savings being twice House B is attributed to House A operating at nearly twice the capacity most of the time and had more duct leakage repaired. This resulted in higher system pressures and therefore greater duct leakage than in House B. Before building modifications, House A used 15.4 kWh per day (32%) more than House B and 3.4 kWh per day (11%) more after modifications. A method of characterizing interstitial spaces using dewpoint measurement is presented and shows that the belly space became 2.6 times more like outdoor conditions after repairs in House A and 2.0 times more in House B.

Withers, C.; Moyer, N.; Chasar, D.; Chandra, S.

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Correcting Thermal Distribution Problems for a Large University Campus  

E-Print Network (OSTI)

Texas A&M University main campus in College Station consists of 114 buildings served by two central plants. The two main campus loops are more than 50 years old with a total piping length for each loop in excess of 13 miles. The main campus has long had a problem with thermal distribution to the 114 buildings served by the central plants. Pressure problems were encountered in the chilled water and hot water distribution system during peak demand periods. The differential pressure between supply and return headers at buildings far from the central plants was negative, in the middle area was neutral, and close to the plant was positive. Various modifications were performed over the years without completely solving this problem. Discovering the real cause could help improve the thermal distribution and help determine how to best operate the system. This paper presents the causes and recommendations for the correction of the thermal distribution problems, which include not only malfunctioning automatic building hydraulic controls, but also some building hydraulic configurations themselves. Based on the findings, the thermal distribution problems will be solved by repairing the controls and retrofitting building hydraulic configurations as needed.

Chen, H.; Deng, S.; Bruner, H. L.; Claridge, D. E.; Turner, W. D.

2002-01-01T23:59:59.000Z

182

NP-complete Problems and Physical Reality  

E-Print Network (OSTI)

Can NP-complete problems be solved efficiently in the physical universe? I survey proposals including soap bubbles, protein folding, quantum computing, quantum advice, quantum adiabatic algorithms, quantum-mechanical nonlinearities, hidden variables, relativistic time dilation, analog computing, Malament-Hogarth spacetimes, quantum gravity, closed timelike curves, and "anthropic computing." The section on soap bubbles even includes some "experimental" results. While I do not believe that any of the proposals will let us solve NP-complete problems efficiently, I argue that by studying them, we can learn something not only about computation but also about physics.

Scott Aaronson

2005-02-12T23:59:59.000Z

183

An electromagnetism metaheuristic for solving the Maximum Betweenness Problem  

Science Conference Proceedings (OSTI)

In this paper we present an electromagnetism (EM) metaheuristic for solving NP hard Maximum Betweenness Problem (MBP). A new encoding scheme with appropriate objective functions is implemented. Specific representation of the individuals enables the EM ... Keywords: Betweenness problem, Combinatorial optimization, Electromagnetism-like mechanism

Vladimir Filipovi?; Aleksandar Kartelj; Dragan Mati?

2013-02-01T23:59:59.000Z

184

One "Cool Tool" That's Helping Repair Your DNA | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

"Cool Tool" That's Helping Repair Your DNA "Cool Tool" That's Helping Repair Your DNA One "Cool Tool" That's Helping Repair Your DNA April 18, 2011 - 1:20pm Addthis Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science What are the key facts? Berkeley Lab's Advanced Light Source produces x-ray light that shines a billion times bright than the sun. Scientists discovered the motor that drives the actual repair of the DNA repair machine called MRN, which is tethered to the rest of the machine in a fairly flexible fashion. Further insight into MRN and other DNA repair machines may also give scientists new insights into fighting some cancers as well as other diseases such as cystic fibrosis. With the arrival of spring, many families are dusting off their tools to make some home improvements. It's worth remembering that nature also has

185

Pemex: Problems and Policy Options  

E-Print Network (OSTI)

American Studies University of California, Berkeley Pemex: Problems and Policy Options David Shields Independent Energy

Shields, David

2006-01-01T23:59:59.000Z

186

Solving the Fast Clock Problem  

Science Conference Proceedings (OSTI)

This power quality (PQ) case study troubleshoots then solves the problem of digital clocks running fast.

2003-12-31T23:59:59.000Z

187

Combustion Turbine Repair Guidelines: Siemens V84.3A (SGT6-4000F)  

Science Conference Proceedings (OSTI)

For more than a decade, the Electric Power Research Institute (EPRI) has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy fram...

2010-01-27T23:59:59.000Z

188

Technical Repair Guidelines for Limitorque Model SMB-000 Valve Actuators: Revision 1  

Science Conference Proceedings (OSTI)

This technical repair guide (TRG) for Limitorque motor-operated valve (MOV) actuator model SMB-000 is the first in a series of documents devoted to the comprehensive maintenance and repair of Limitorque actuators. This guide provides instructions for engineering, operations, and maintenance personnel on MOV actuator repair, maintenance, adjustment, and troubleshooting methods. Originally published in 1989, this document has now been thoroughly revised (Revision 1) to incorporate new information and techn...

1994-10-02T23:59:59.000Z

189

Development of Laser Weld Repair, Cladding, and Heat Treatment Technology for Alloy 600 RPV Penetrations  

Science Conference Proceedings (OSTI)

EPRI has developed innovative laser weld repair technology for Alloy 600 reactor pressure vessel (RPV) head penetrations in pressure water reactors (PWRs). The repair technology consists of an Nd:YAG laser, fiber optic delivery system, optical assembly (weld head), welding filler metal feed system, and manipulator. The laser system will be used to address the repair of axially oriented cracks, stress relief, and cladding operations.

1998-06-29T23:59:59.000Z

190

Conference Proceedings: EPRI-RRAC Fifth International Conference on Welding and Repair Technology for Power Plants  

Science Conference Proceedings (OSTI)

The 2002 Fifth International Conference on Welding and Repair Technology for Power Plants included presentations of case histories, emerging welding technologies, and demonstrated repair techniques and approaches. These proceedings provide technical information discussed during this conference on the repair of steam turbine rotors, disks, blades, piping, steam generators, headers, reactor pressure vessel internals, valves, pumps, combustion turbines, and other components. Sessions include nuclear and fos...

2002-10-17T23:59:59.000Z

191

Note: A Graph-Theoretical Approach to Level of Repair Analysis  

E-Print Network (OSTI)

Aug 29, 2004... of repair and maintenance facilities to minimize overall life-cycle costs. ... Category 2: Applications -- OR and Management Sciences ...

192

Improving Repair Quality of Turbine Nozzles Using SA650 Braze Alloy  

Science Conference Proceedings (OSTI)

improved repairs for key gas turbine components. Airfoil components of High Pressure and Low. Pressure turbines (HPT and LPT) are subject to wear and ...

193

Note: A Graph-Theoretical Approach to Level of Repair Analysis  

E-Print Network (OSTI)

Aug 29, 2004 ... Acquisition Management System at www.ams.mod.uk/ams). ... LORA seeks to determine an optimal provision of repair and maintenance.

194

Compliant mechanisms  

E-Print Network (OSTI)

The motivation for this work has been a variety of motions like navigation of pipelines, insertion operations in assembly, and gripping actions, which require the adaptation of the mechanism to the external constraints, rather than avoid them. To this effect, efforts have been made in building mechanisms that obtain the required degrees of freedom through deformations rather than explicit joints in them. Although the use of many joints provides the required number of degrees of freedom, it does so at the cost of making the system very bulky and complex. With the advent of new polymers, the possibility of building joint-free mechanisms that fulfil the requirements of adaptation has increased. Based on this approach, a Magneto Active Polymer (MAP) material has been developed here at the Texas A\\&M University, in which the actuation is performed by the conversion of electromagnetic energy into mechanical energy. The initial experimentation has proved the vast potential of the use of such a material and a few mechanisms like a magneto active peristaltic pump, have been designed and tested for the first time using this material. In this mechanism, the pumping action is obtained when a moving magnetic field produces peristaltic waves in the magneto active material shaped as a tube. Also for the first time, experiments have been conducted to analyze the response of the MAP material to a pulsating magnetic field with the intent of using the experimental results to develop a model of the MAP. In developing the design for the peristaltic pump and other conceptual models described in this thesis, ideas have been drawn from the different modes of locomotion and actuators present in lower organisms. These have been good sources of inspiration for the work done in this thesis and they have been documented in detail.

Venkataraghavan, Janarthanan T

2001-01-01T23:59:59.000Z

195

Blade reliability collaborative : collection of defect, damage and repair data.  

SciTech Connect

The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.

2013-04-01T23:59:59.000Z

196

Mechanism Design without Money via Stable Matching  

E-Print Network (OSTI)

Mechanism design without money has a rich history in social choice literature. Due to the strong impossibility theorem by Gibbard and Satterthwaite, exploring domains in which there exist dominant strategy mechanisms is one of the central questions in the field. We propose a general framework, called the generalized packing problem (\\gpp), to study the mechanism design questions without payment. The \\gpp\\ possesses a rich structure and comprises a number of well-studied models as special cases, including, e.g., matroid, matching, knapsack, independent set, and the generalized assignment problem. We adopt the agenda of approximate mechanism design where the objective is to design a truthful (or strategyproof) mechanism without money that can be implemented in polynomial time and yields a good approximation to the socially optimal solution. We study several special cases of \\gpp, and give constant approximation mechanisms for matroid, matching, knapsack, and the generalized assignment problem. Our result for ge...

Chen, Ning; Lu, Pinyan

2011-01-01T23:59:59.000Z

197

Acceleration Mechanisms  

E-Print Network (OSTI)

Glossary I. Background and context of the subject II. Stochastic acceleration III. Resonant scattering IV. Diffusive shock acceleration V. DSA at multiple shocks VI. Applications of DSA VII. Acceleration by parallel electric fields VIII. Other acceleration mechanisms IX. Future directions X. Appendix: Quasilinear equations XI. Bibliography

Melrose, D B

2009-01-01T23:59:59.000Z

198

Problem 2-Lexicographic Order  

E-Print Network (OSTI)

Problem: For complex numbers z = a + bi ? C and w = c + di ? C define ”z ? w ” if either a ordering of C”. (Question I) Prove that this turns C into and ordered set. (Question II) Is this an ordered field? (no) (Question III) Does it have the least-upper-bound property? (no) We will first review the definitions of order and ordered set from Rudin [R]. We will then show that under the lexicographic ordering C is an ordered set. Definition 1. Let S be a set. An order on S is a relation, denoted by ?, with the following two properties: (i) If x ? S and y ? S then one and only one of the statements is true. x ? y, x = y, y ? x (ii) If x, y, z ? S, if x ? y and y ? z, then x ? z.

Jacob Bower

2008-01-01T23:59:59.000Z

199

Kolkata Restaurant Problem as a generalised El Farol Bar Problem  

E-Print Network (OSTI)

Generalisation of the El Farol bar problem to that of many bars here leads to the Kolkata restaurant problem, where the decision to go to any restaurant or not is much simpler (depending on the previous experience of course, as in the El Farol bar problem). This generalised problem can be exactly analysed in some limiting cases discussed here. The fluctuation in the restaurant service can be shown to have precisely an inverse cubic behavior, as widely seen in the stock market fluctuations.

Chakrabarti, Bikas K

2007-01-01T23:59:59.000Z

200

Applying problem-structuring methods to problems in computer security  

Science Conference Proceedings (OSTI)

Solutions to security problems, particularly ones involving cryptography, have typically been approached through the Inside-Out Threat Model, "this is our solution and whatever it addresses is the threat". Email encryption/signing and SSL/TLS are two ... Keywords: problem-structuring methods, soft operations research, soft systems methodology, wicked problems

Peter Gutmann

2011-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

TA Orientation 2005 Activity 6 Problem Solving: Cowboy Bob Problem  

E-Print Network (OSTI)

TA Orientation 2005 Activity 6 Problem Solving: Cowboy Bob Problem Page 61 Below is a problem from the outlaws. #12;TA Orientation 2005 Activity 6 (continued) Page 62 Notes: #12;TA Orientation 2005 Activity 7. #12;TA Orientation 2005 Activity 7 (continued) Page 64 Answer Sheet for Activity 7 1. Examine your

Minnesota, University of

202

Optimal control problems, curves of pursuit.  

E-Print Network (OSTI)

??We study a class of problems known as pursuit-evasion problems (PE). These problems can be understood as special cases of optimal control problems. After describing… (more)

Moiseeva, Svetlana

2011-01-01T23:59:59.000Z

203

Development of a Mechanics Reasoning Inventory  

E-Print Network (OSTI)

Strategic knowledge is required to appropriately organize procedures and concepts to solve problems. We are developing a standardized instrument assessing strategic knowledge in the domain of introductory mechanics. This ...

Pawl, Andrew

2012-01-01T23:59:59.000Z

204

Hospitals - Medical - Backup Generator Problems  

Science Conference Proceedings (OSTI)

This power quality (PQ) case study presents the investigation of problems while testing a backup generator at a hospital.

2003-12-31T23:59:59.000Z

205

A Systematic Stochastic Petri Net Based Methodology for Transformer Fault Diagnosis and Repair Actions  

Science Conference Proceedings (OSTI)

Transformer fault diagnosis and repair is a complex task that includes many possible types of faults and demands special trained personnel. Moreover, the minimization of the time needed for transformer fault diagnosis and repair is an important task ... Keywords: power system reliability, stochastic petri nets, transformer fault diagnosis

P. S. Georgilakis; J. A. Katsigiannis; K. P. Valavanis; A. T. Souflaris

2006-02-01T23:59:59.000Z

206

Change-point detection in failure intensity: A case study with repairable artillery systems  

Science Conference Proceedings (OSTI)

Repairable systems can experience unexpected environmental changes over long operational periods. Such changes affect the incidence of failures, causing different system failure patterns before and after the changes. In this article, we propose an informational ... Keywords: Change-point, Homogeneous Poisson process, Modified information criterion, Repairable system, Schwarz information criterion, Statistical trend test

Suk Joo Bae; Byeong Min Mun; Kyung Yong Kim

2013-01-01T23:59:59.000Z

207

Manual of Bearing Failures and Repair in Power Plant Rotating Equipment  

Science Conference Proceedings (OSTI)

Bearing failures are a leading cause of unavailability for power plant rotating machinery, often resulting in prolonged forced outages and costly repairs. This manual, which assists utilities in identifying bearing failure modes and selecting remedial actions to prevent future failures, provides guidelines for repair techniques.

1991-08-08T23:59:59.000Z

208

Repair Technology for Degraded Pressure Vessel and Heat Exchanger Shells: RRAC Task 91  

Science Conference Proceedings (OSTI)

The ability to repair pressure vessels and heat exchangers offers utilities significant cost savings compared to replacing these components. This is especially the case if outage time and loss of production are factored into the cost of replacement. This guide provides a review of various current and proposed repair methods that can be used for pressure vessel and heat exchanger applications.

2002-12-02T23:59:59.000Z

209

State-of-the-Art Weld Repair Technology for Rotating Components  

Science Conference Proceedings (OSTI)

Deregulation of the power industry, increased competition, enhanced environmental regulations, and aging or degraded equipment continue to place greater economic pressures on utilities. Weld repair of rotors and discs offers a viable means of extending the life of in-service rotors and discs. This report provides comprehensive repair guidelines for utilities.

1997-07-30T23:59:59.000Z

210

Resource constrained scheduling problem at U.S. Naval Shipyards  

E-Print Network (OSTI)

Submarine repair schedules are some of the most complex schedules seen in project management. Repairs of a nuclear U.S. submarine are resource constrained since resources are divided among approximately thirty shops (e.g. ...

Nawara, Terrence M. (Terrence Michael)

2013-01-01T23:59:59.000Z

211

Anglers' fishing problem  

E-Print Network (OSTI)

The considered model will be formulated as related to "the fishing problem" even if the other applications of it are much more obvious. The angler goes fishing. He uses various techniques and he has at most two fishing rods. He buys a fishing ticket for a fixed time. The fishes are caught with the use of different methods according to the renewal processes. The fishes' value and the inter arrival times are given by the sequences of independent, identically distributed (i.i.d.) random variables with the known distribution functions. It forms the marked renewal--reward process. The angler's measure of satisfaction is given by the difference between the utility function, depending on the value of the fishes caught, and the cost function connected with the time of fishing. In this way, the angler's relative opinion about the methods of fishing is modelled. The angler's aim is to have as much satisfaction as possible and additionally he has to leave the lake before a fixed moment. Therefore his goal is to find two...

Karpowicz, Anna

2011-01-01T23:59:59.000Z

212

Problem frames and software engineering  

Science Conference Proceedings (OSTI)

A general account is given of the problem frames approach to the development of software-intensive systems, assuming that the reader is already familiar with its basic ideas. The approach is considered in the light of the long-standing aspiration of ... Keywords: Problem frame, Problems, Software

Michael Jackson

2005-11-01T23:59:59.000Z

213

A generalized linear-quadratic model incorporating reciprocal time pattern of radiation damage repair  

Science Conference Proceedings (OSTI)

Purpose: It has been conventionally assumed that the repair rate for sublethal damage (SLD) remains constant during the entire radiation course. However, increasing evidence from animal studies suggest that this may not the case. Rather, it appears that the repair rate for radiation-induced SLD slows down with increasing time. Such a slowdown in repair would suggest that the exponential repair pattern would not necessarily accurately predict repair process. As a result, the purpose of this study was to investigate a new generalized linear-quadratic (LQ) model incorporating a repair pattern with reciprocal time. The new formulas were tested with published experimental data. Methods: The LQ model has been widely used in radiation therapy, and the parameter G in the surviving fraction represents the repair process of sublethal damage with T{sub r} as the repair half-time. When a reciprocal pattern of repair process was adopted, a closed form of G was derived analytically for arbitrary radiation schemes. The published animal data adopted to test the reciprocal formulas. Results: A generalized LQ model to describe the repair process in a reciprocal pattern was obtained. Subsequently, formulas for special cases were derived from this general form. The reciprocal model showed a better fit to the animal data than the exponential model, particularly for the ED50 data (reduced {chi}{sup 2}{sub min} of 2.0 vs 4.3, p = 0.11 vs 0.006), with the following gLQ parameters: {alpha}/{beta} = 2.6-4.8 Gy, T{sub r} = 3.2-3.9 h for rat feet skin, and {alpha}/{beta} = 0.9 Gy, T{sub r} = 1.1 h for rat spinal cord. Conclusions: These results of repair process following a reciprocal time suggest that the generalized LQ model incorporating the reciprocal time of sublethal damage repair shows a better fit than the exponential repair model. These formulas can be used to analyze the experimental and clinical data, where a slowing-down repair process appears during the course of radiation therapy.

Huang, Zhibin; Mayr, Nina A.; Lo, Simon S.; Wang, Jian Z.; Jia Guang; Yuh, William T. C.; Johnke, Roberta [Department of Radiation Oncology, East Carolina University, Greenville, North Carolina 27834 (United States); Department of Radiation Oncology, Ohio State University, Columbus, Ohio 43210 (United States); Department of Radiation Oncology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio 44106 (United States); Department of Radiation Oncology, Ohio State University, Columbus, Ohio 43210 (United States); Department of Radiology, Ohio State University, Columbus, Ohio 43210 (United States); Department of Radiation Oncology, East Carolina University, Greenville, North Carolina, 27834 (United States)

2012-01-15T23:59:59.000Z

214

Conserved XPB Core Structure and Motifs for DNA Unwinding:Implications for Pathway Selection of Transcription or ExcisionRepair  

Science Conference Proceedings (OSTI)

The human xeroderma pigmentosum group B (XPB) helicase is essential for transcription, nucleotide excision repair, and TFIIH functional assembly. Here, we determined crystal structures of an Archaeoglobus fulgidus XPB homolog (AfXPB) that characterize two RecA-like XPB helicase domains and discover a DNA damage recognition domain (DRD), a unique RED motif, a flexible thumb motif (ThM), and implied conformational changes within a conserved functional core. RED motif mutations dramatically reduce helicase activity, and the DRD and ThM, which flank the RED motif, appear structurally as well as functionally analogous to the MutS mismatch recognition and DNA polymerase thumb domains. Substrate specificity is altered by DNA damage, such that AfXPB unwinds dsDNA with 3' extensions, but not blunt-ended dsDNA, unless it contains a lesion, as shown for CPD or (6-4) photoproducts. Together, these results provide an unexpected mechanism of DNA unwinding with Implications for XPB damage verification in nucleotide excision repair.

Fan, Li; Arval, Andrew S.; Cooper, Priscilla K.; Iwai, Shigenori; Hanaoka, Fumio; Tainer, John A.

2005-04-01T23:59:59.000Z

215

OEIM 210. Industrial Mechanics III 4 cr. Air compressors, sliding surface bearings, boiler maintenance, boiler  

E-Print Network (OSTI)

OEIM 210. Industrial Mechanics III 4 cr. Air compressors, sliding surface bearings, boiler maintenance, boiler tube repairs, basic arc and gas welding, measurement tools, gauge glass maintenance, heat by employer and instructor on boiler inspection and cleaning, centrifugal pumps, basic rigging, piping

Castillo, Steven P.

216

Health physics support for thermal shield repair at Connecticut Yankee  

Science Conference Proceedings (OSTI)

This article describes the radiation and safety controls used by Connecticut Yankee Atomic Power Company to support underwater repair work on the Haddam Neck Plant's core barrel thermal shield. The work was conducted by divers in the reactor cavity using remote tools and protected by a specially-constructed physical barrier that restricted their movements to a carefully defined and thoroughly surveyed area. A unique dosimetry test rig was used to determine the dose rate profiles within the work areas, and all underwater survey equipment was qualified against personnel dosimetric devices. Underwater operations were monitored and controlled by remote means (video surveillance and dosimetry telemetry), and health physics technicians were rotated through job coverage to avoid complacency and maximize training opportunities. A single, hot particle event occurred during one dive, but this was identified almost immediately and controlled to prevent excessive exposure to the diver.

Nevelos, W.F.; Gates, W.J. (Connecticut Yankee Atomic Power Co., East Hampton, CT (United States))

1988-10-01T23:59:59.000Z

217

Interfacial instability and DNA fork reversal by repair proteins  

E-Print Network (OSTI)

A repair protein like RecG moves the stalled replication fork in the direction from the zipped to the unzipped state of DNA. It is proposed here that a softening of the zipped-unzipped interface at the fork results in the front propagating towards the unzipped side. In this scenario, an ordinary helicase destabilizes the zipped state locally near the interface and the fork propagates towards the zipped side. The softening of the interface can be produced by the aromatic interaction, predicted from crystal structure, between RecG and the nascent broken base pairs at the Y-fork. A numerical analysis of the model also reveals the possibility of a stop and go type motion.

Somendra M. Bhattacharjee

2009-09-03T23:59:59.000Z

218

Removal of Dioxin Contamination for Gas Turbine Generator Set Repair  

SciTech Connect

Decontamination projects are typically undertaken in the interest of reducing disposal costs. This goal can be achieved because decontamination concentrates the contaminant into a smaller volume or changes its form so that a lower cost disposal technology becomes available. Less frequently, decontamination adds value back to the fouled structure or contaminated piece of equipment. This removal of dioxins from a gas turbine generator set is one of the latter cases. A multi-million dollar piece of equipment could have been destined for the scrap pile. Instead, an innovative, non-destructive decontamination technology, developed under EPA and DOE demonstration programs has was employed so that the set could repaired and put back into service. The TechXtractchemical decontamination technology reduced surface dioxin / furan concentrations from as high as 24,000 ng / m2 to less than 25 ng / m2 and below detection limits.

Fay, W. S.; Borah, R.E.

2003-02-25T23:59:59.000Z

219

The Consent Problem in International Law  

E-Print Network (OSTI)

nuclear   weapons.     More   problems   implicating   more   people   make   the   consent   problem   more   complex  

Guzman, Andrew

2011-01-01T23:59:59.000Z

220

TRANSIENT QUANTUM MECHANICAL PROCESSES  

SciTech Connect

Our principal objective has centered on the development of sophisticated computational techniques to solve the time-dependent Schroedinger equation that governs the evolution of quantum mechanical systems. We have perfected two complementary methods, discrete variable representation and real space product formula, that show great promise in solving these complicated temporal problems. We have applied these methods to the interaction of laser light with molecules with the intent of not only investigating the basic mechanisms but also devising schemes for actually controlling the outcome of microscopic processes. Lasers now exist that produce pulses of such short duration as to probe a molecular process many times within its characteristic period--allowing the actual observation of an evolving quantum mechanical system. We have studied the potassium dimer as an example and found agreement with experimental changes in the intermediate state populations as a function of laser frequency--a simple control prescription. We have also employed elaborate quantum chemistry programs to improve the accuracy of basic input such as bound-bound and bound-free coupling moments. These techniques have far-ranging applicability; for example, to trapped quantum systems at very low temperatures such as Bose-Einstein condensates.

L. COLLINS; J. KRESS; R. WALKER

1999-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Quantum Mechanics: Structures, Axioms and Paradoxes  

E-Print Network (OSTI)

Quantum Mechanics: Structures, Axioms and Paradoxes Diederik Aerts Center Leo Apostel, Brussels present an analysis of quantum mechanics and its problems and para- doxes taking into account the results that have been obtained during the last two decades by investigations in the field of `quantum structures re

Aerts, Diederik

222

Development and validation of bonded composite doubler repairs for commercial aircraft.  

Science Conference Proceedings (OSTI)

A typical aircraft can experience over 2,000 fatigue cycles (cabin pressurizations) and even greater flight hours in a single year. An unavoidable by-product of aircraft use is that crack, impact, and corrosion flaws develop throughout the aircraft's skin and substructure elements. Economic barriers to the purchase of new aircraft have placed even greater demands on efficient and safe repair methods. The use of bonded composite doublers offers the airframe manufacturers and aircraft maintenance facilities a cost effective method to safely extend the lives of their aircraft. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is now possible to bond a single Boron-Epoxy composite doubler to the damaged structure. The FAA's Airworthiness Assurance Center at Sandia National Labs (AANC), Boeing, and Federal Express completed a pilot program to validate and introduce composite doubler repair technology to the U.S. commercial aircraft industry. This project focused on repair of DC-10 fuselage structure and its primary goal was to demonstrate routine use of this repair technology using niche applications that streamline the design-to-installation process. As composite doubler repairs gradually appear in the commercial aircraft arena, successful flight operation data is being accumulated. These commercial aircraft repairs are not only demonstrating the engineering and economic advantages of composite doubler technology but they are also establishing the ability of commercial maintenance depots to safely adopt this repair technique. This report presents the array of engineering activities that were completed in order to make this technology available for widespread commercial aircraft use. Focused laboratory testing was conducted to compliment the field data and to address specific issues regarding damage tolerance and flaw growth in composite doubler repairs. Fatigue and strength tests were performed on a simulated wing repair using a substandard design and a flawed installation. In addition, the new Sol-Gel surface preparation technique was evaluated. Fatigue coupon tests produced Sol-Gel results that could be compared with a large performance database from conventional, riveted repairs. It was demonstrated that not only can composite doublers perform well in severe off-design conditions (low doubler stiffness and presence of defects in doubler installation) but that the Sol-Gel surface preparation technique is easier and quicker to carry out while still producing optimum bonding properties. Nondestructive inspection (NDI) methods were developed so that the potential for disbond and delamination growth could be monitored and crack growth mitigation could be quantified. The NDI methods were validated using full-scale test articles and the FedEx aircraft installations. It was demonstrated that specialized NDI techniques can detect flaws in composite doubler installations before they reach critical size. Probability of Detection studies were integrated into the FedEx training in order to quantify the ability of aircraft maintenance depots to properly monitor these repairs. In addition, Boeing Structural Repair and Nondestructive Testing Manuals were modified to include composite doubler repair and inspection procedures. This report presents the results from the FedEx Pilot Program that involved installation and surveillance of numerous repairs on operating aircraft. Results from critical NDI evaluations are reported in light of damage tolerance assessments for bonded composite doublers. This work has produced significant interest from airlines and aircraft manufacturers. The successful Pilot Program produced flight performance history to establish the durability of bonded composite patches as a permanent repair on commercial aircraft structures. This report discusses both the laboratory data and Pilot Program results from repair installations on operating aircraft to introduce composite doubler repairs into mainstream commercial aircraft use.

Roach, Dennis Patrick; Rackow, Kirk A.

2007-07-01T23:59:59.000Z

223

Pooling problems: relaxations and discretizations  

E-Print Network (OSTI)

The classical minimum cost network flow problem seeks to find the optimal way of sending ... The front-end scheduling, also referred to as the crude oil operation.

224

Moods, wicked problems, and learning  

Science Conference Proceedings (OSTI)

Wicked problems and learning environments present tough mood challenges for leaders and teachers. Telepresence and sensory gadgets are unlikely to replace physical presence in these areas.

Peter J. Denning

2013-03-01T23:59:59.000Z

225

Problems in High Energy Astrophysics  

E-Print Network (OSTI)

This contribution discusses some of the main problems in high energy astrophysics, and the perspectives to solve them using different types of "messengers": cosmic rays, photons and neutrinos

Lipari, Paolo

2008-01-01T23:59:59.000Z

226

Problems in High Energy Astrophysics  

E-Print Network (OSTI)

This contribution discusses some of the main problems in high energy astrophysics, and the perspectives to solve them using different types of "messengers": cosmic rays, photons and neutrinos

Paolo Lipari

2008-08-04T23:59:59.000Z

227

Hedging Problems with Stochastic Parameters  

NLE Websites -- All DOE Office Websites (Extended Search)

the problems of quadratic hedging and mean-variance portfolio selection in an incomplete market with continuous trading, multiple assets, and Brownian information. In particular,...

228

The Split Variational Inequality Problem  

E-Print Network (OSTI)

Sep 20, 2010 ... lines of research related to our notion of the CVIP. ...... Imaging, Therapy Planning and Inverse Problems, Medical Physics Pub# lishing ...

229

The underwater radiance distribution problem  

E-Print Network (OSTI)

THE UNDERWATER RADIANCE DISTRIBUTION PROBLEM S. Q. DuntleyFunction of Depth in an Underwater Environment," which firsta Function of Depth in an Underwater Environment," which has

Duntley, Seibert Q

1959-01-01T23:59:59.000Z

230

R Symmetry and the Mu Problem  

E-Print Network (OSTI)

A natural origin for the mu and B parameters of weak scale supersymmetric theories is proposed, applicable to any supersymmetry breaking messenger scale between the weak and Planck scales. Although quite general, it requires supersymmetric interactions to respect an R symmetry with definite quantum numbers, and it requires some new scale of symmetry breaking. The required R symmetry distinguishes the Higgs boson from the sneutrino, preserves baryon number in operators of dimension four and five, and contains R parity so that the lightest superpartner is stable. This origin for mu works for a variety of mediation mechanisms, including gauge mediation, gaugino mediation, and boundary condition breaking of supersymmetry. In any of these mediation schemes, our mechanism leads to a real B parameter, and the supersymmetric CP problem is solved. This R symmetry may naturally arise from supersymmetric theories in higher dimensions.

Lawrence J. Hall; Yasunori Nomura; Aaron Pierce

2002-04-04T23:59:59.000Z

231

Microsoft Word - SPR Emergency Pipeline Repair, 2013-2017 NEPA.docx  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Emergency Pipeline and Piping Repair, 2013-2017 Emergency Pipeline and Piping Repair, 2013-2017 Description: Subcontractor shall shall provide all labor, materials, equipment, supervision, transportation and services required to perform emergency repairs on the SPR system site piping (including underground fire protection systems and offsite pipelines). Subcontractor shall mobilize equipment to perform excavation, backfill, hydrostatic testing, welding and cutting, blasting, coating and painting of large and small diameter piping systems on the SPR facilities and offsite pipelines. Subcontractor shall also assist in emergency exercises by assemblying temporary piping spools and positioning pump skids and temporary supports. This NEPA document covers the period from 2013-2017.

232

INDEXING MECHANISM  

DOE Patents (OSTI)

A device is presented for loading and unloading fuel elements containing material fissionable by neutrons of thermal energy. The device comprises a combination of mechanical features Including a base, a lever pivotally attached to the base, an Indexing plate on the base parallel to the plane of lever rotation and having a plurality of apertures, the apertures being disposed In rows, each aperture having a keyway, an Index pin movably disposed to the plane of lever rotation and having a plurality of apertures, the apertures being disposed in rows, each aperture having a keyway, an index pin movably disposed on the lever normal to the plane rotation, a key on the pin, a sleeve on the lever spaced from and parallel to the index pin, a pair of pulleys and a cable disposed between them, an open collar rotatably attached to the sleeve and linked to one of the pulleys, a pin extending from the collar, and a bearing movably mounted in the sleeve and having at least two longitudinal grooves in the outside surface.

Kock, L.J.

1959-09-22T23:59:59.000Z

233

Boundary stabilization of transmission problems  

E-Print Network (OSTI)

We study the transmission problem in bounded domains with dissipative boundary conditions. Under some natural assumptions, we prove uniform bounds of the corresponding resolvents on the real axis at high frequency, and as a consequence, we obtain free of eigenvalues regions. As an application, we get exponential decay of the energy of the solutions of the correpsonding mixed boundary value problems.

Fernando Cardoso; Georgi Vodev

2009-10-20T23:59:59.000Z

234

Mechanical Design  

SciTech Connect

The particle beam of the SXR (soft x-ray) beam line in the LCLS (Linac Coherent Light Source) has a high intensity in order to penetrate through samples at the atomic level. However, the intensity is so high that many experiments fail because of severe damage. To correct this issue, attenuators are put into the beam line to reduce this intensity to a level suitable for experimentation. Attenuation is defined as 'the gradual loss in intensity of any flux through a medium' by [1]. It is found that Beryllium and Boron Carbide can survive the intensity of the beam. At very thin films, both of these materials work very well as filters for reducing the beam intensity. Using a total of 12 filters, the first 9 being made of Beryllium and the rest made of Boron Carbide, the beam's energy range of photons can be attenuated between 800 eV and 9000 eV. The design of the filters allows attenuation for different beam intensities so that experiments can obtain different intensities from the beam if desired. The step of attenuation varies, but is relative to the thickness of the filter as a power function of 2. A relationship for this is f(n) = x{sub 0}2{sup n} where n is the step of attenuation desired and x{sub 0} is the initial thickness of the material. To allow for this desired variation, a mechanism must be designed within the test chamber. This is visualized using a 3D computer aided design modeling tool known as Solid Edge.

2010-08-25T23:59:59.000Z

235

An internal seal for repairing natural gas mains  

E-Print Network (OSTI)

Joint leakage from low pressure natural gas distribution mains (typical value: 0.25 ft[superscript 3] at 6 inwg gas pressure) is a persistent source of maintenance problems for utitlites. External encapsulation is the usual ...

Cooper, Samuel A.

1984-01-01T23:59:59.000Z

236

Assessing Expertise in Quantum Mechanics using Categorization Task  

Science Conference Proceedings (OSTI)

We discuss the categorization of 20 quantum mechanics problems by 6 physics professors and 22 undergraduate students from two honors?level quantum mechanics courses. Professors and students were asked to categorize the problems based upon similarity of solution. We also had individual discussions with professors who categorized the problems. Faculty members’ categorizations were overall rated better than those of students by three faculty members who evaluated all of the categorizations. But the categories created by faculty members were more diverse compared to the uniformity of the categories they created when asked to categorize introductory mechanics problems.

Shih?Yin Lin; Chandralekha Singh

2009-01-01T23:59:59.000Z

237

On The Problem of Vacuum energy in Brane Theories  

E-Print Network (OSTI)

We point out that modern brane theories suffer from a severe vacuum energy problem. To be specific, the Casimir energy associated with the matter fields confined to the brane, is stemming from the one and the same localization mechanism which forms the brane itself, and is thus generically unavoidable. Possible practical solutions are discussed, including in particular spontaneously broken supersymmetry, and quantum mechanically induced brane tension.

Gurwich, Ilya; Davidson, Aharon

2009-01-01T23:59:59.000Z

238

A Protein that Repairs Damage to Cancer Cells | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

An X-ray Vortex on the Horizon? An X-ray Vortex on the Horizon? How Two Drops Become One Scientists Discover How Nanocluster Contaminants Increase Risk of Spreading Mobile RNA is Poised and Ready Glass Does a Double-Take Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed A Protein that Repairs Damage to Cancer Cells MAY 5, 2008 Bookmark and Share The ABH2-DNA complex. A team of University of Chicago scientists has shown how two proteins locate and repair damaged genetic material inside cells. Because one of the proteins detects and repairs DNA damage that may result from a certain type of cancer therapy, the researchers raised the possibility of designing a molecule that could interfere with the repair process, making cancer

239

ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND BREAK REPAIR CAPACITY IN HUMAN DIPLOID FIBROBLASTS  

NLE Websites -- All DOE Office Websites (Extended Search)

ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND BREAK REPAIR CAPACITY IN HUMAN DIPLOID FIBROBLASTS Paul F. Wilson, John M. Hinz, Peter B. Nham, Salustra S. Urbin, Cynthia B. Thomas, Irene M. Jones, and Larry H. Thompson Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA The induction of bi-stranded clustered DNA damage (BCD), which includes direct DNA double-strand breaks (DSBs), is a hallmark of ionizing radiation (IR) exposure. Incorrectly repaired DSBs can cause chromosomal rearrangements and an increased risk of genomic instability and cancer. Because there is polymorphic variation in DNA repair genes and much of this variation is predicted to have a functional impact, healthy people likely vary in their capacity to repair DSBs and other BCD. This project

240

In-Situ Repairs of Oil Industry Pipelines, Tanks and Vessels by ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Metal arc welding under oil (MAW-UO) is a new, revolutionary process to repair a pipeline, tank or vessel by welding in case of flaws and ...

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Plug repairs of marine glass fiber / vinyl ester laminates subjected to uniaxial tension  

E-Print Network (OSTI)

Glass fiber/vinyl ester composite laminates are currently being used and proposed for the hulls, bulkheads, and superstructures of large ships. This thesis examines the effectiveness of the repair of such laminates using ...

Michelis, Alexandros

2009-01-01T23:59:59.000Z

242

Maintenance and repair: a simulation model for field service with condition-based maintenance  

Science Conference Proceedings (OSTI)

In this paper, we consider field service in which service providers are responsible for maintaining equipment performance. To do so, preventive maintenance work is usually required in addition to repairs. Field service managers are often faced with the ...

Yiqing Lin; Arthur Hsu; Ravi Rajamani

2002-12-01T23:59:59.000Z

243

Tiny Terminators: New Micro-Robots Assemble, Repair Themselves and Are Surprisingly Strong  

Energy.gov (U.S. Department of Energy (DOE))

Tiny robots that can assemble and repair themselves? Watch a video of Argonne National Laboratory's micro-robots that easily perform tasks that can challenge other robots, including moving objects that are larger than themselves.

244

Modeling and centralization of strategic inventory for repairable and long lead-time spare parts  

E-Print Network (OSTI)

This thesis develops an optimal inventory model for repairable and long leadtime spare parts for an Engine overhaul business. In addition, it presents a business case for centralization of inventory. Pratt & Whitney purchased ...

Duncan, Tyeliah Elaine

2011-01-01T23:59:59.000Z

245

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

NLE Websites -- All DOE Office Websites (Extended Search)

Induced DNA Damage Signaling and Repair Responses in Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System Yanrong Su, Jarah Meador and Adayabalam S. Balajee Center for Radiological Research, College of Physicians and Surgeons, Columbia University, 630 West, 168th Street, New York, NY 10032. Exposure to ionizing radiation (IR) inflicts a wide variety of lesions in the genomic DNA. Among them, DNA double strand break (DSB) is considered to be the critical lesion for most of the deleterious radiation effects including carcinogenesis. Much of our knowledge on induction and repair kinetics of DSB has come from studies in two dimensional cell culture systems. However, the damage signaling and repair responses to DSB in tissue microenvironment are largely unknown. Knowledge of tissue responses to

246

Review of Maintenance and Repair Times for Components in Technological Facilities  

SciTech Connect

This report is a compilation of some unique component repair time data and it also presents citations of more extensive reports where lists of repair times can be found. This collection of information should support analysts who seek to quantify maintainability and availability of high technology and nuclear energy production systems. While there are newer sources of repair time information, most, if not all, of the newer sources are proprietary and cannot be shared. This report offers data that, while older, is openly accessible and can serve as reasonable estimates of repair times, at least for initial studies. Some times were found for maintenance times in radiation environments, and some guidance for multiplicative factors to use to account for work in contamination areas.

L. C. Cadwallader

2012-11-01T23:59:59.000Z

247

Spreadsheet modelling for solving combinatorial problems: The vendor selection problem  

E-Print Network (OSTI)

Spreadsheets have grown up and became very powerful and easy to use tools in applying analytical techniques for solving business problems. Operations managers, production managers, planners and schedulers can work with them in developing solid and practical Do-It-Yourself Decision Support Systems. Small and Medium size organizations, can apply OR methodologies without the presence of specialized software and trained personnel, which in many cases cannot afford anyway. This paper examines an efficient approach in solving combinatorial programming problems with the use of spreadsheets. A practical application, which demonstrates the approach, concerns the development of a spreadsheet-based DSS for the Multi Item Procurement Problem with Fixed Vendor Cost. The DSS has been build using exclusively standard spreadsheet feature and can solve real problems of substantial size. The benefits and limitations of the approach are also discussed.

Ipsilandis, Pandelis G

2008-01-01T23:59:59.000Z

248

Computationally efficient Bayesian inference for inverse problems.  

SciTech Connect

Bayesian statistics provides a foundation for inference from noisy and incomplete data, a natural mechanism for regularization in the form of prior information, and a quantitative assessment of uncertainty in the inferred results. Inverse problems - representing indirect estimation of model parameters, inputs, or structural components - can be fruitfully cast in this framework. Complex and computationally intensive forward models arising in physical applications, however, can render a Bayesian approach prohibitive. This difficulty is compounded by high-dimensional model spaces, as when the unknown is a spatiotemporal field. We present new algorithmic developments for Bayesian inference in this context, showing strong connections with the forward propagation of uncertainty. In particular, we introduce a stochastic spectral formulation that dramatically accelerates the Bayesian solution of inverse problems via rapid evaluation of a surrogate posterior. We also explore dimensionality reduction for the inference of spatiotemporal fields, using truncated spectral representations of Gaussian process priors. These new approaches are demonstrated on scalar transport problems arising in contaminant source inversion and in the inference of inhomogeneous material or transport properties. We also present a Bayesian framework for parameter estimation in stochastic models, where intrinsic stochasticity may be intermingled with observational noise. Evaluation of a likelihood function may not be analytically tractable in these cases, and thus several alternative Markov chain Monte Carlo (MCMC) schemes, operating on the product space of the observations and the parameters, are introduced.

Marzouk, Youssef M.; Najm, Habib N.; Rahn, Larry A.

2007-10-01T23:59:59.000Z

249

Topical Report: Application of the Excavate and Weld Repair Process for Repair and Mitigation of Alloy 182 and 82 in PWRs  

Science Conference Proceedings (OSTI)

Weld overlay is a mature technology for the repair of PWR nozzle dissimilar metal butt welds that are susceptible to primary water stress corrosion cracking (PWSCC). While weld-overlay technology continues to serve the industry well, a viable alternative is desirable for large-bore nozzle welds (>24 inches outside diameter) to minimize the time required to perform the repair and to serve in cases in which significant physical interferences near the Alloy 82/182 dissimilar metal weld would make it difficu...

2010-12-20T23:59:59.000Z

250

Inverse Problems in Heat Transfer  

E-Print Network (OSTI)

This chapter presents a stochastic modeling and statistical inference approach to the solution of inverse problems in thermal transport systems. Of particular interest is the inverse heat conduction problem (IHCP) of estimating an unknown boundary heat flux in a conducting solid given temperature data within the domain. Even though deterministic sequential and whole time domain estimation methods have been applied with success over the years for the solution of such problems, we herein introduce stochastic approaches to representing and solving the IHCP. As most engineering systems and processes operate in an uncertain environment, it becomes increasingly important to address their analysis and inverse design in a stochastic manner using statistical data-driven prior and concurrent information on the system response. Recent advances in spectral stochastic modeling, computational Bayesian and spatial statistics enable complete and e#cient solution procedures to such problems. Two distinct approaches to the IHCP are presented in this chapter one based on spectral stochastic modeling and the other on Bayesian inference. Although these techniques are discussed in the context of the IHCP, the methodologies presented are general and applicable to design and estimation problems in other more complex problems in thermal transport systems including problems in the presence of convection, radiation and conduction. 1

Nicholas Zabaras

2004-01-01T23:59:59.000Z

251

Technical Repair Guidelines for the Limitorque Model SMB-00 Valve Actuator  

Science Conference Proceedings (OSTI)

This technical repair guideline (TRG) is the second in a series of documents devoted to comprehensive maintenance and repair of the motor-operated Limitorque SMB-00 valve actuator. The Limitorque SMB-00 valve actuator is mounted on a nonrotating rising stem valve and is applicable to other types of valves and installation arrangements. This report was written with the latest available information, however, changes to the actuator's design, parts availability, etc. may supersede this document but will not...

1995-06-30T23:59:59.000Z

252

Welding and Repair Technology Center: Essential and Emergency Service Water System Issues  

Science Conference Proceedings (OSTI)

Because of the numerous ASME Code and Regulatory (Nuclear Regulatory Commission) documents addressing operability and repair of through-wall leakage in class 2 and 3 systems, inconsistencies exist in their interpretation and application. This report is intended to summarize and clarify the current Code and Regulatory requirements and provisions applicable to operability and repair of essential and emergency service water systems with leakage through the pressure boundary.

2010-10-29T23:59:59.000Z

253

RESTORING A DAMAGED 16-YEAR -OLD INSULATING POLYMER CONCRETE DIKE OVERLAY: REPAIR MATERIALS AND TECHNOLOGIES.  

Science Conference Proceedings (OSTI)

The objective of this program was to design and formulate organic polymer-based material systems suitable for repairing and restoring the overlay panels of insulating lightweight polymer concrete (ILPC) from the concrete floor and slope wall of a dike at KeySpan liquefied natural gas (LNG) facility in Greenpoint, Brooklyn, NY, just over sixteen years ago. It also included undertaking a small-scale field demonstration to ensure that the commercial repairing technologies were applicable to the designed and formulated materials.

SUGAMA,T.

2007-01-01T23:59:59.000Z

254

Physicalism versus quantum mechanics  

E-Print Network (OSTI)

Foundations of Quantum Mechanics. (Princeton UniversityMind, Matter, and Quantum Mechanics, (Springer, Berlin & NewMindful Universe: Quantum Mechanics and the Participating

Stapp, Henry P; Theoretical Physics Group; Physics Division

2009-01-01T23:59:59.000Z

255

Parallel solution of recurrence problems  

Science Conference Proceedings (OSTI)

An mth-order recurrence problem is defined as the computation of the sequence x1,..., xN, where x1 = f(ai, xi-1,...,xi-m), ...

P. M. Kogge

1974-03-01T23:59:59.000Z

256

Connectivity problem in wireless networks  

Science Conference Proceedings (OSTI)

We study the complexity of the following connectivity problem in wireless networks: for a given placement of n nodes in the plane, the goal is to compute a channel and power assignment that forms strongly connected communication structure spanning ...

Dariusz R. Kowalski; Mariusz A. Rokicki

2010-09-01T23:59:59.000Z

257

Surrogate Guderley Test Problem Definition  

SciTech Connect

The surrogate Guderley problem (SGP) is a 'spherical shock tube' (or 'spherical driven implosion') designed to ease the notoriously subtle initialization of the true Guderley problem, while still maintaining a high degree of fidelity. In this problem (similar to the Guderley problem), an infinitely strong shock wave forms and converges in one-dimensional (1D) cylindrical or spherical symmetry through a polytropic gas with arbitrary adiabatic index {gamma}, uniform density {rho}{sub 0}, zero velocity, and negligible pre-shock pressure and specific internal energy (SIE). This shock proceeds to focus on the point or axis of symmetry at r = 0 (resulting in ostensibly infinite pressure, velocity, etc.) and reflect back out into the incoming perturbed gas.

Ramsey, Scott D. [Los Alamos National Laboratory; Shashkov, Mikhail J. [Los Alamos National Laboratory

2012-07-06T23:59:59.000Z

258

Mathematical Problems of Thermoacoustic Tomography  

E-Print Network (OSTI)

Thermoacoustic tomography (TAT) is a newly emerging modality in biomedical imaging. It combines the good contrast of electromagnetic and good resolution of ultrasound imaging. The mathematical model of TAT is the observability problem for the wave equation: one observes the data on a hyper-surface and reconstructs the initial perturbation. In this dissertation, we consider several mathematical problems of TAT. The first problem is the inversion formulas. We provide a family of closed form inversion formulas to reconstruct the initial perturbation from the observed data. The second problem is the range description. We present the range description of the spherical mean Radon transform, which is an important transform in TAT. The next problem is the stability analysis for TAT. We prove that the reconstruction of the initial perturbation from observed data is not H¨older stable if some observability condition is violated. The last problem is the speed determination. The question is whether the observed data uniquely determines the ultrasound speed and initial perturbation. We provide some initial results on this issue. They include the unique determination of the unknown constant speed, a weak local uniqueness, a characterization of the non-uniqueness, and a characterization of the kernel of the linearized operator.

Nguyen, Linh V.

2010-08-01T23:59:59.000Z

259

The Consistent Vehicle Routing Problem  

SciTech Connect

In the small package shipping industry (as in other industries), companies try to differentiate themselves by providing high levels of customer service. This can be accomplished in several ways, including online tracking of packages, ensuring on-time delivery, and offering residential pickups. Some companies want their drivers to develop relationships with customers on a route and have the same drivers visit the same customers at roughly the same time on each day that the customers need service. These service requirements, together with traditional constraints on vehicle capacity and route length, define a variant of the classical capacitated vehicle routing problem, which we call the consistent VRP (ConVRP). In this paper, we formulate the problem as a mixed-integer program and develop an algorithm to solve the ConVRP that is based on the record-to-record travel algorithm. We compare the performance of our algorithm to the optimal mixed-integer program solutions for a set of small problems and then apply our algorithm to five simulated data sets with 1,000 customers and a real-world data set with more than 3,700 customers. We provide a technique for generating ConVRP benchmark problems from vehicle routing problem instances given in the literature and provide our solutions to these instances. The solutions produced by our algorithm on all problems do a very good job of meeting customer service objectives with routes that have a low total travel time.

Groer, Christopher S [ORNL; Golden, Bruce [University of Maryland; Edward, Wasil [American University

2009-01-01T23:59:59.000Z

260

Single Cell Mechanics BIOMATERIALS  

E-Print Network (OSTI)

Single Cell Mechanics BIOMATERIALS Our goal is to develop fundamental tools to measure the response of live cells to mechanical stimulation. The mechanisms by which cells convert mechanical forces evaluate the underlying mechanisms of cell mechanics. Objective Impact and Customers · Cancer, heart

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

DNA repair decline during mouse spermiogenesis results in the accumulation of heritable DNA damage  

Science Conference Proceedings (OSTI)

The post-meiotic phase of mouse spermatogenesis (spermiogenesis) is very sensitive to the genomic effects of environmental mutagens because as male germ cells form mature sperm they progressively lose the ability to repair DNA damage. We hypothesized that repeated exposures to mutagens during this repair-deficient phase result in the accumulation of heritable genomic damage in mouse sperm that leads to chromosomal aberrations in zygotes after fertilization. We used a combination of single or fractionated exposures to diepoxybutane (DEB), a component of tobacco smoke, to investigate how differential DNA repair efficiencies during the three weeks of spermiogenesis affected the accumulation of DEB-induced heritable damage in early spermatids (21-15 days before fertilization, dbf), late spermatids (14-8 dbf) and sperm (7- 1 dbf). Analysis of chromosomalaberrations in zygotic metaphases using PAINT/DAPI showed that late spermatids and sperm are unable to repair DEB-induced DNA damage as demonstrated by significant increases (P<0.001) in the frequencies of zygotes with chromosomal aberrations. Comparisons between single and fractionated exposures suggested that the DNA repair-deficient window during late spermiogenesis may be less than two weeks in the mouse and that during this repair-deficient window there is accumulation of DNA damage in sperm. Finally, the dose-response study in sperm indicated a linear response for both single and repeated exposures. These findings show that the differential DNA repair capacity of post-meioitic male germ cells has a major impact on the risk of paternally transmitted heritable damage and suggest that chronic exposures that may occur in the weeks prior to fertilization because of occupational or lifestyle factors (i.e, smoking) can lead to an accumulation of genetic damage in sperm and result in heritable chromosomal aberrations of paternal origin.

Marchetti, Francesco; Marchetti, Francesco; Wryobek, Andrew J

2008-02-21T23:59:59.000Z

262

DNA Repair Decline During Mouse Spermiogenesis Results in the Accumulation of Heritable DNA Damage  

Science Conference Proceedings (OSTI)

The post-meiotic phase of mouse spermatogenesis (spermiogenesis) is very sensitive to the genomic effects of environmental mutagens because as male germ cells form mature sperm they progressively lose the ability to repair DNA damage. We hypothesized that repeated exposures to mutagens during this repair-deficient phase result in the accumulation of heritable genomic damage in mouse sperm that leads to chromosomal aberrations in zygotes after fertilization. We used a combination of single or fractionated exposures to diepoxybutane (DEB), a component of tobacco smoke, to investigate how differential DNA repair efficiencies during the three weeks of spermiogenesis affected the accumulation of DEB-induced heritable damage in early spermatids (21-15 days before fertilization, dbf), late spermatids (14-8 dbf) and sperm (7-1 dbf). Analysis of chromosomal aberrations in zygotic metaphases using PAINT/DAPI showed that late spermatids and sperm are unable to repair DEB-induced DNA damage as demonstrated by significant increases (P<0.001) in the frequencies of zygotes with chromosomal aberrations. Comparisons between single and fractionated exposures suggested that the DNA repair-deficient window during late spermiogenesis may be less than two weeks in the mouse and that during this repair-deficient window there is accumulation of DNA damage in sperm. Finally, the dose-response study in sperm indicated a linear response for both single and repeated exposures. These findings show that the differential DNA repair capacity of post-meioitic male germ cells has a major impact on the risk of paternally transmitted heritable damage and suggest that chronic exposures that may occur in the weeks prior to fertilization because of occupational or lifestyle factors (i.e, smoking) can lead to an accumulation of genetic damage in sperm and result in heritable chromosomal aberrations of paternal origin.

Marchetti, Francesco; Marchetti, Francesco; Wyrobek, Andrew J.

2007-12-01T23:59:59.000Z

263

Strange Bedfellows: Quantum Mechanics and Data Mining  

SciTech Connect

Last year, in 2008, I gave a talk titled Quantum Calisthenics. This year I am going to tell you about how the work I described then has spun off into a most unlikely direction. What I am going to talk about is how one maps the problem of finding clusters in a given data set into a problem in quantum mechanics. I will then use the tricks I described to let quantum evolution lets the clusters come together on their own.

Weinstein, Marvin; /SLAC

2009-12-16T23:59:59.000Z

264

Physical Interpretations of Nilpotent Quantum Mechanics  

E-Print Network (OSTI)

Nilpotent quantum mechanics provides a powerful method of making efficient calculations. More importantly, however, it provides insights into a number of fundamental physical problems through its use of a dual vector space and its explicit construction of vacuum. Physical interpretation of the nilpotent formalism is discussed with respect to boson and baryon structures, the mass-gap problem, zitterbewgung, Berry phase, renormalization, and related issues.

Peter Rowlands

2010-04-09T23:59:59.000Z

265

Gas Turbine Repair Guideline: GE 6FA/FA+e, Volume 19: GE MS6001 Model FA/FA+e  

Science Conference Proceedings (OSTI)

For more than a decade, the Electric Power Research Institute (EPRI) has been developing gas turbine hot section component repair and coating guidelines to assist utilities in the refurbishment of these critical and expensive parts. Utilities, generators, and repair vendors have used these guidelines to perform repairs on blades, turbine vanes, and combustion hardware. Guidelines now exist for a variety of conventional and advanced General Electric, Siemens/Westinghouse, Alstom, and Mitsubishi heavy ...

2013-12-11T23:59:59.000Z

266

Bohmian Mechanics and the Meaning of the Wave Function  

E-Print Network (OSTI)

Bohmian Mechanics and the Meaning of the Wave Function D. D¨urr Mathematisches Institut der predictive successes, quantum mechanics has, since its inception some seventy years ago, been plagued the measurement problem is not merely one of the conceptual difficulties of quantum mechanics

Goldstein, Sheldon

267

Discrete mechanics, optimal control and formation flying spacecraft  

E-Print Network (OSTI)

Discrete mechanics, optimal control and formation flying spacecraft Oliver Junge Center-Bl¨obaum partially supported by the CRC 376 Oliver Junge Discrete mechanics, optimal control and formation flying spacecraft p.1 #12;Outline mechanical optimal control problem direct discretization of the variational

Patrick, George

268

On the Faithful Interpretation of Pure Wave Mechanics  

E-Print Network (OSTI)

On the Faithful Interpretation of Pure Wave Mechanics Jeffrey A. Barrett ABSTRACT Given Hugh-state formulation of pure wave mechanics arguably qualifies as an empirically acceptable physical theory resolution to both the determinate record and the probability problems encountered by pure wave mechanics

Barrett, Jeffrey A.

269

ON THE FAITHFUL INTERPRETATION OF PURE WAVE MECHANICS  

E-Print Network (OSTI)

ON THE FAITHFUL INTERPRETATION OF PURE WAVE MECHANICS JEFFREY A. BARRETT In the long version of his Ph.D. thesis, Hugh Everett III developed pure wave mechanics as a way of solving the quantum measurement problem faced by the standard von Neumann-Dirac collapse formulation of quantum mechanics.1 Pure

Wüthrich, Christian

270

Key-Based Problem Decomposition for Relational Constraint Satisfaction Problems  

Science Conference Proceedings (OSTI)

Constraint satisfaction problems (CSP) are often posed over data residing in relational database systems, which serve as passive data-storage back ends. Several studies have demonstrated a number of important advantages to having database systems capable ... Keywords: constraint processing, databases, decomposition

James J. Lu; Sebastien Siva

2011-11-01T23:59:59.000Z

271

The role of mismatch repair in mediating cellular sensitivity to cisplatin : the Escherichia coli methyl-directed repair paradigm  

E-Print Network (OSTI)

The anticancer drug cisplatin is in widespread use but its mechanism of action is only poorly understood. Moreover, human cancers acquire resistance to the drug, which limits its clinical utility. A paradox in the field ...

Robbins, Jennifer L

2006-01-01T23:59:59.000Z

272

Development of a rapid design procedure for emergency repair of bridge columns using fiber-reinforced polymers  

E-Print Network (OSTI)

with success including wet layup, winding with wet tow orthen installed; whereas, wet layup based fabrication of FRPfor emergency repair. FRP wet layup also allows for ease of

Slater, Susan E.

2008-01-01T23:59:59.000Z

273

Effect of laser e LED radiations associated or not on dorsal cutaneous wound repair in a rodent model: histologic study.  

E-Print Network (OSTI)

??The aim of the present investigation was to evaluate histologically tissue repair on dorsal cutaneous wounds in a rodent model treated with Laser and/or LED,… (more)

Ana Paula Cavalcanti de Sousa

2008-01-01T23:59:59.000Z

274

Current problems in plasma spray processing  

SciTech Connect

This detailed report summarizes 8 contributions from a thermal spray conference that was held in late 1991 at Brookhaven National Laboratory (Upton, Long Island, NY, USA). The subject of ``Plasma Spray Processing`` is presented under subject headings of Plasma-particle interactions, Deposit formation dynamics, Thermal properties of thermal barrier coatings, Mechanical properties of coatings, Feed stock materials, Porosity: An integrated approach, Manufacture of intermetallic coatings, and Synchrotron x-ray microtomographic methods for thermal spray materials. Each section is intended to present a concise statement of a specific practical and/or scientific problem, then describe current work that is being performed to investigate this area, and finally to suggest areas of research that may be fertile for future activity.

Berndt, C.C.; Brindley, W.; Goland, A.N.; Herman, H.; Houck, D.L.; Jones, K.; Miller, R.A.; Neiser, R.; Riggs, W.; Sampath, S.; Smith, M.; Spanne, P. [State Univ. of New York, Stony Brook, NY (United States). Thermal Spray Lab.

1991-12-31T23:59:59.000Z

275

Current problems in plasma spray processing  

SciTech Connect

This detailed report summarizes 8 contributions from a thermal spray conference that was held in late 1991 at Brookhaven National Laboratory (Upton, Long Island, NY, USA). The subject of Plasma Spray Processing'' is presented under subject headings of Plasma-particle interactions, Deposit formation dynamics, Thermal properties of thermal barrier coatings, Mechanical properties of coatings, Feed stock materials, Porosity: An integrated approach, Manufacture of intermetallic coatings, and Synchrotron x-ray microtomographic methods for thermal spray materials. Each section is intended to present a concise statement of a specific practical and/or scientific problem, then describe current work that is being performed to investigate this area, and finally to suggest areas of research that may be fertile for future activity.

Berndt, C.C.; Brindley, W.; Goland, A.N.; Herman, H.; Houck, D.L.; Jones, K.; Miller, R.A.; Neiser, R.; Riggs, W.; Sampath, S.; Smith, M.; Spanne, P. (State Univ. of New York, Stony Brook, NY (United States). Thermal Spray Lab.)

1991-01-01T23:59:59.000Z

276

Steam Boiler Control Specification Problem:  

E-Print Network (OSTI)

Our solution to the specification problem in the specification language TLA+ is based on a model of operation where several components proceed synchronously. Our first specification concerns a simplified controller and abstracts from many details given in the informal problem description. We successively add modules to build a model of the state of the steam boiler, detect failures, and model message transmission. We give a more detailed controller specification and prove that it refines the abstract controller. We also address the relationship between the physical state of the steam boiler and the model maintained by the controller and discuss the reliability of failure detection. Finally, we discuss the implementability of our specification.

Tla Solution Frank; Frank Le Ke; Stephan Merz

1996-01-01T23:59:59.000Z

277

WHERE MULTIFUNCTIONAL DNA REPAIR PROTEINS MEET: MAPPING THE INTERACTION DOMAINS BETWEEN XPG AND WRN  

Science Conference Proceedings (OSTI)

The rapid recognition and repair of DNA damage is essential for the maintenance of genomic integrity and cellular survival. Multiple complex and interconnected DNA damage responses exist within cells to preserve the human genome, and these repair pathways are carried out by a specifi c interplay of protein-protein interactions. Thus a failure in the coordination of these processes, perhaps brought about by a breakdown in any one multifunctional repair protein, can lead to genomic instability, developmental and immunological abnormalities, cancer and premature aging. This study demonstrates a novel interaction between two such repair proteins, Xeroderma pigmentosum group G protein (XPG) and Werner syndrome helicase (WRN), that are both highly pleiotropic and associated with inherited genetic disorders when mutated. XPG is a structure-specifi c endonuclease required for the repair of UV-damaged DNA by nucleotide excision repair (NER), and mutations in XPG result in the diseases Xeroderma pigmentosum (XP) and Cockayne syndrome (CS). A loss of XPG incision activity results in XP, whereas a loss of non-enzymatic function(s) of XPG causes CS. WRN is a multifunctional protein involved in double-strand break repair (DSBR), and consists of 3’–5’ DNA-dependent helicase, 3’–5’ exonuclease, and single-strand DNA annealing activities. Nonfunctional WRN protein leads to Werner syndrome, a premature aging disorder with increased cancer incidence. Far Western analysis was used to map the interacting domains between XPG and WRN by denaturing gel electrophoresis, which separated purifi ed full length and recombinant XPG and WRN deletion constructs, based primarily upon the length of each polypeptide. Specifi c interacting domains were visualized when probed with the secondary protein of interest which was then detected by traditional Western analysis using the antibody of the secondary protein. The interaction between XPG and WRN was mapped to the C-terminal region of XPG as well as the C-terminal region of WRN. The physical interaction between XPG and WRN links NER, (made evident by the disease XP) with DSBR, which imparts additional knowledge of the overlapping nature of these two proteins and the previously distinct DNA repair pathways they are associated with. Since genomic integrity is constantly threatened by both endogenous and exogenous (internal and external) damage, understanding the roles of these proteins in coordinating DNA repair processes with replication will signifi cantly further understanding how defects instigate physiological consequences in response to various DNA damaging sources. This ultimately contributes to our understanding of cancer and premature aging.

Rangaraj, K.; Cooper, P.K.; Trego, K.S.

2009-01-01T23:59:59.000Z

278

Enhancement of DNA repair capacity of mammalian cells by carcinogen treatment  

SciTech Connect

To determine whether DNA excision repair is enhanced in mammalian cells in response to DNA damage, as it is in bacteria as part of the SOS response, we used an expression vector-host cell reactivation assay to measure cellular DNA repair capacity. When UV-damaged chloramphenicol acetyltransferase (CAT) vector DNA was introduced into monkey cells (CV-1), the level of CAT activity was inversely related to the UV fluence due to inhibition of CAT gene expression by UV photoproducts. When CV-1 cells were treated with either UV radiation or mitomycin C, 24-48 h before transfection, CAT expression from the UV-irradiated plasmid was increased. This increase also occurred in a line of normal human cells, but not in repair-deficient human xeroderma pigmentosum cells. We confirmed that this increase in CAT expression was due to repair, and not to production of damage-free templates by recombination; the frequency of generation of supF+ recombinants after transfection with UV-irradiated pZ189 vectors carrying different point mutations in the supF gene did not significantly increase in carcinogen-treated CV-1 cells. From these results we conclude that carcinogen treatment enhances the excision-repair capacity of normal mammalian cells.

Protic, M.; Roilides, E.; Levine, A.S.; Dixon, K.

1988-07-01T23:59:59.000Z

279

Exotic Species What's the Problem?  

E-Print Network (OSTI)

are estimated to cost about $138 billion in environmental damage and losses each year. Non-native plants $100 million annually in damage to water pipes and filtration systems, and in control costs. · Brown-300 power outages/yr, numerous bites of children, etc. #12;What's the Problem? · Melaleuca tree --destroyed

Callender, Craig

280

Inverse scattering problem with isobars  

SciTech Connect

The inverse scattering problem is solved for a covariant, isobar-dominated scattering amplitude (including inelasticity). Application is made to the ..pi..N P/sub 33/ channel, with the ..pi..N ..delta.. vertex function and isobar bare mass as results.

Londergan, J.T.; Moniz, E.J.

1977-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Substation automation problems and possibilities  

SciTech Connect

The evolutionary growth in the use and application of microprocessors in substations has brought the industry to the point of considering integrated substation protection, control, and monitoring systems. An integrated system holds the promise of greatly reducing the design, documentation, and implementation cost for the substation control, protection, and monitoring systems. This article examines the technical development path and the present implementation problems.

Smith, H.L.

1996-10-01T23:59:59.000Z

282

Open Problems in $?$ Particle Condensation  

E-Print Network (OSTI)

$\\alpha$ particle condensation is a novel state in nuclear systems. We briefly review the present status on the study of $\\alpha$ particle condensation and address the open problems in this research field: $\\alpha$ particle condensation in heavier systems other than the Hoyle state, linear chain and $\\alpha$ particle rings, Hoyle-analogue states with extra neutrons, $\\alpha$ particle condensation related to astrophysics, etc.

Y. Funaki; M. Girod; H. Horiuchi; G. Roepke; P. Schuck; A. Tohsaki; T. Yamada

2010-03-05T23:59:59.000Z

283

The metro map layout problem  

Science Conference Proceedings (OSTI)

We initiate a new problem of automatic metro map layout. In general, a metro map consists of a set of lines which have intersections or overlaps. We define a set of aesthetic criteria for good metro map layouts and present a method to produce ...

Seok-Hee Hong; Damian Merrick; Hugo A. D. do Nascimento

2004-09-01T23:59:59.000Z

284

Drinking Water Problems: Radionuclides (Spanish)  

E-Print Network (OSTI)

Radionuclides in drinking water can cause serious health problems for people. This publication explains what the sources of radionuclides in water are, where high levels have been found in Texas, how they affect health and how to treat water to remove them.

Lesikar, Bruce J.; Melton, Rebecca; Hare, Michael; Hopkins, Janie; Dozier, Monty

2006-12-21T23:59:59.000Z

285

A nonlinear programming test problem  

Science Conference Proceedings (OSTI)

Figure 1 is a flow diagram of the chemical process. The test problem was a hydrocarbon refrigeration process in which the feed stream (stream number 1 of Figure 1) is a vapor mixture of ethane, propane, and n-butane (subscripts e, p and b, respectively) ...

D. M. Himmelblau

1979-07-01T23:59:59.000Z

286

Semidefinite Relaxations of Ordering Problems  

E-Print Network (OSTI)

Jan 19, 2011 ... The quadratic ordering problem does not seem to have attracted ... 2 Linear Ordering as a Linear Program in 0-1 variables .... Instead of the Lovász-Schrijver lifting procedure, ...... Review of Economics and Statistics, 18, 1936. ... IEEE Transactions on Systems, Man, and Cybernetics, 11(2):109–125, 1981.

287

Statistical Inference in Inverse Problems  

E-Print Network (OSTI)

Inverse problems have gained popularity in statistical research recently. This dissertation consists of two statistical inverse problems: a Bayesian approach to detection of small low emission sources on a large random background, and parameter estimation methods for partial differential equation (PDE) models. Source detection problem arises, for instance, in some homeland security applications. We address the problem of detecting presence and location of a small low emission source inside an object, when the background noise dominates. The goal is to reach the signal-to-noise ratio levels on the order of 10^-3. We develop a Bayesian approach to this problem in two-dimension. The method allows inference not only about the existence of the source, but also about its location. We derive Bayes factors for model selection and estimation of location based on Markov chain Monte Carlo simulation. A simulation study shows that with sufficiently high total emission level, our method can effectively locate the source. Differential equation (DE) models are widely used to model dynamic processes in many fields. The forward problem of solving equations for given parameters that define the DEs has been extensively studied in the past. However, the inverse problem of estimating parameters based on observed state variables is relatively sparse in the statistical literature, and this is especially the case for PDE models. We propose two joint modeling schemes to solve for constant parameters in PDEs: a parameter cascading method and a Bayesian treatment. In both methods, the unknown functions are expressed via basis function expansion. For the parameter cascading method, we develop the algorithm to estimate the parameters and derive a sandwich estimator of the covariance matrix. For the Bayesian method, we develop the joint model for data and the PDE, and describe how the Markov chain Monte Carlo technique is employed to make posterior inference. A straightforward two-stage method is to first fit the data and then to estimate parameters by the least square principle. The three approaches are illustrated using simulated examples and compared via simulation studies. Simulation results show that the proposed methods outperform the two-stage method.

Xun, Xiaolei

2012-05-01T23:59:59.000Z

288

Printed Circuit Board Maintenance, Repair, and Testing Guide  

Science Conference Proceedings (OSTI)

Printed circuit boards (PCBs) are an assembly of electronic and electro-mechanical components, such as relays and switches. The printed circuit (PC) board assembly provides multiple functions based on its application and intended service. It is an integral part of many instruments and/or instrumentation systems.

2003-10-30T23:59:59.000Z

289

Microsoft PowerPoint - Bull Shoals U1 repair MSB edit 3.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

Bull Shoals Unit 1 161kV Bull Shoals Unit 1 161kV Switchyard Feeder Repair Bull Shoals Unit 1 161kV Bull Shoals Unit 1 161kV Switchyard Feeder Repair Switchyard Feeder Repair Mark Dixson Little Rock District US Army Corps US Army Corps of Engineers of Engineers ® ® One Corps Serving The Army and the Nation * Original Equipment - 52 years old. * Unit 1 Oil filled cable pothead failed and exploded on Sept 6 2006. * Resulting fire and fire suppression damaged oil insulated cable system * Minor damage to power plant. Background Background Background US Army Corps US Army Corps of Engineers of Engineers ® ® One Corps Serving The Army and the Nation * Transformer Unit 2 damaged and removed from service. * Cause of fire - Failure of Pothead stress cone assembly and build up of combustible gas * Power Plant lost all power and went in the

290

The Role of DNA double-strand break repair in cellular response to low  

NLE Websites -- All DOE Office Websites (Extended Search)

DNA double-strand break repair in cellular response to low DNA double-strand break repair in cellular response to low dose radiation exposure. David J. Chen Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas TX 75390 It has been assumed that molecular pathways that involved in the biological response for low dose of radiation should be similar to those for high dose radiation in general. The low dose-rate effect and DNA double-strand break repair are inextricably linked in mammalian cells. It has been reported that mammalian mutant cells deficient in nonhomologous end join (NHEJ) pathway have little or no cellular recovery when expose to low-dose-rate radiation. Recently, it has also been reported that cells deficient in

291

Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec.  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Docket No. EO-05-01. Regarding the planned line outage, scheduled for Feb. 20 through Mar. 6, I am requesting that the residents near the plant be moved for the duration of the outage to protect their health. Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 More Documents & Publications Letter from Elizabeth Chimento and Poul Hertel to the Federal Energy Regulatory Commission Re: District of Columbia Public Service Commission Emergency Petition and Complaint Docket No. EL05-145-000 Re: Potomac River Generating Station Department of Energy Case No.

292

Evaluation of bisphenol E cyanate ester for the resin-injection repair of advanced composites  

SciTech Connect

This thesis is a compilation of a general introduction and literature review that ties together the subsequent chapters which consist of two journal articles that have yet to be submitted for publication. The overall topic relates to the evaluation and application of a new class of cyanate ester resin with unique properties that lend it applicable to use as a resin for injection repair of high glass transition temperature polymer matrix composites. The first article (Chapter 2) details the evaluation and optimization of adhesive properties of this cyanate ester and alumina nanocomposites under different conditions. The second article (Chapter 3) describes the development and evaluation of an injection repair system for repairing delaminations in polymer matrix composites.

Wilber Yaote Lio

2009-12-19T23:59:59.000Z

293

Statistical Mechanics of Dictionary Learning  

E-Print Network (OSTI)

Finding a basis matrix (dictionary) by which objective signals are represented sparsely is of major relevance in various scientific and technological fields. We consider a problem to learn a dictionary from a set of training signals. We employ techniques of statistical mechanics of disordered systems to evaluate the size of the training set necessary to typically succeed in the dictionary learning. The results indicate that the necessary size is much smaller than previously estimated, which theoretically supports and/or encourages the use of dictionary learning in practical situations.

Sakata, Ayaka

2012-01-01T23:59:59.000Z

294

Annual Inventory Troubleshooting Checklist Problem Solutions  

E-Print Network (OSTI)

Annual Inventory Troubleshooting Checklist Problem Solutions Duplicate tag number Send email to am;Annual Inventory Troubleshooting Checklist Problem Solutions Personal property Send email to am

Li, Mo

295

Test instances for the traffic assignment problem  

E-Print Network (OSTI)

Test instances for the traffic assignment problem. F. Babonneau. ?. J.-P. Vial. ?. January 8, 2008. Abstract. This short note on the Traffic Assignment Problem ...

296

MechanicalTesting  

NLE Websites -- All DOE Office Websites (Extended Search)

structures, validation of encapsulant cure stress models, development of frac- ture mechanics tests for use in adhesion studies and understanding the failure mechanism of...

297

An Oil Pipeline Design Problem  

Science Conference Proceedings (OSTI)

We consider a given set of offshore platforms and onshore wells producing known (or estimated) amounts of oil to be connected to a port. Connections may take place directly between platforms, well sites, and the port, or may go through connection points ... Keywords: Algorithms: interactive branch-and-bound with valid inequalities. industries, Applications: design problem-formulation and analysis. programming, Integer, Networks/graphs, Petroleum/natural gas: oil pipeline network design

Jack Brimberg; Pierre Hansen; Keh-Wei Lin; Nenad Mladenovic; Michèle Breton

2003-03-01T23:59:59.000Z

298

Including cognitive biases and distance-based rewards in a connectionist model of complex problem solving  

Science Conference Proceedings (OSTI)

We present a cognitive, connectionist-based model of complex problem solving that integrates cognitive biases and distance-based and environmental rewards under a temporal-difference learning mechanism. The model is tested against experimental data obtained ... Keywords: Cognitive biases, Computational modeling, Distance-reduction heuristic, Problem solving, Reinforcement learning, Temporal-difference learning

Frédéric Dandurand; Thomas R. Shultz; Arnaud Rey

2012-01-01T23:59:59.000Z

299

On Iterative Solution for Linear Complementarity Problem with an $H_{+}$-Matrix  

Science Conference Proceedings (OSTI)

The numerous applications of the linear complementarity problem (LCP) in, e.g., the solution of linear and convex quadratic programming, free boundary value problems of fluid mechanics, and moving boundary value problems of economics make ... Keywords: $H_+$-matrices, $M$-matrices, $P$-matrices, (block) modulus algorithm, LCP, iterative schemes, modified AOR method, modulus-based matrix splitting iteration methods, real positive definite matrices, scaled extrapolation, strictly diagonally dominant matrices

A. Hadjidimos; M. Lapidakis; M. Tzoumas

2012-01-01T23:59:59.000Z

300

The mechanical behavior of heavily overconsolidated resedimented Boston Blue Clay  

E-Print Network (OSTI)

Geotechnical engineers encounter some of the most challenging problems in heavily overconsolidated soils. Clays under this condition originated in nature or man-made construction. This thesis investigates the mechanical ...

Vargas Bustamante, Albalyra Geraldine

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Quantum-mechanical linear filtering of random signal sequences  

Science Conference Proceedings (OSTI)

The problem of estimating a member of a scalar random signal sequence with quantum-mechanical measurements is considered. The minimum variance linear estimator based on an optimal present quantum measurement and optimal linear processing of past measurements ...

J. Baras; R. Harger; Young Park

1976-01-01T23:59:59.000Z

302

Mechanism of pressure welding  

SciTech Connect

Thesis. The mechanism in polycrystalline aluminum, copper, silver, and gold was investigated. (19 figures) (DLC)

Mohamed, H.A.E.F.

1973-12-01T23:59:59.000Z

303

CARTESIAN MECHANICS* Sophie Roux  

E-Print Network (OSTI)

1 CARTESIAN MECHANICS* Sophie Roux (Centre Alexandre Koyré, EHESS, Paris) Introduction For many the search for a mathematical treatment of phenomena, on the other hand the demand for mechanical as the typical mechanical philosopher, and contrasted as such to the founder of mechanics as a science, namely

Paris-Sud XI, Université de

304

INTRODUCTION TO THE MECHANICS  

E-Print Network (OSTI)

INTRODUCTION TO THE MECHANICS OF A CONTINUOUS MEDIUM Lawrence E. Malvern Professor of Mechanics princi- ples common to all branches of solid and fluid mechanics, designed to appeal to the intuition science. The book arose from the need to provide a general preparation in contin- uum mechanics

Kaminski, Edouard

305

Graduate quantum mechanics reform  

Science Conference Proceedings (OSTI)

We address four main areas in which graduatequantum mechanics education can be improved: course content

L. D. Carr; S. B. McKagan

2009-01-01T23:59:59.000Z

306

On the equivalence of linear complementarity problems  

Science Conference Proceedings (OSTI)

We show that the Extended Linear Complementarity Problem (ELCP) can be recast as a standard Linear Complementarity Problem (LCP) provided that the surplus variables or the feasible set of the ELCP are bounded. Since many extensions of the LCP are special ... Keywords: Complementarity problems, Integer programming, Linear complementarity problem, Nonlinear algorithms, Optimization

B. De Schutter; W. P. M. H. Heemels; A. Bemporad

2002-08-01T23:59:59.000Z

307

The Effect of Price Expectations on Auto-Repair Price Quotes  

E-Print Network (OSTI)

We show that price expectations alter outcomes in a negotiated price environment. By experimentally manipulating the price expectations that consumers communicate to firms, we show that consumers ’ price expectations alter outcomes by directly changing firms ’ behavior. We implement a large-scale field experiment in which callers request price quotes from automotive repair shops. We find that repair shops quote higher prices if they know that callers ’ perception of the market price is high. We find that women are quoted higher prices than men when callers signal that they are uninformed about market prices. However, gender differences disappear when callers mention an expected price for the repair. Finally, we find that repair shops are more likely to offer In an environment in which prices customarily are negotiated, it can be difficult and time-consuming for consumers to gather enough information to create a good estimate of the market price. This phenomenon is common to many industries: buying a car entails lengthy negotiations in which dealers want to know about a consumer’s current vehicle, her financing preferences, the available

Meghan R. Busse; Florian Zettelmeyer

2012-01-01T23:59:59.000Z

308

Osteochondral defect repair using a novel tissue engineering approach: Sheep model study  

Science Conference Proceedings (OSTI)

Porous calcium polyphosphate (CPP) constructs of desired density were formed by sintering CPP powders. Articular cartilage was formed on these constructs in cell culture over an 8-week period with the resulting cartilage layer forming on the CPP surface ... Keywords: Articular cartilage repair, implants, in vitro and in vivo studies, osteochondral implants, porous calcium polyphosphate, tissue engineering, tissue ingrowth

R. M. Pilliar; R. A. Kandel; M. D. Grynpas; P. Zalzal; M. Hurtig

2007-01-01T23:59:59.000Z

309

Simulation and validation of repair welding and heat treatment of an alloy 718 plate  

Science Conference Proceedings (OSTI)

This paper describes simulation of repair welding and heat treatment together with measurements for validation. The possibility to replace global heat treatment with local using induction heating is evaluated with respect to obtained residual stresses. ... Keywords: Dislocation density based plasticity model, Finite element simulation, Heat treatment, Induction heating, Residual stress measurement

M. Fisk; A. LundbäCk

2012-10-01T23:59:59.000Z

310

A key-based coordination algorithm for dynamic readiness and repair service coordination  

Science Conference Proceedings (OSTI)

This paper describes an agent application for the coordination of air-craft repair, refit, refuel, and rearm teams in a dynamic setting. The paper also presents a new algorithm for dynamic distributed service team coordination and compares its performance ... Keywords: TAEMS, coordination, dynamic, intelligent agents, multi-agent systems, real-time, teams

Tom Wagner; Valerie Guralnik; John Phelps

2003-07-01T23:59:59.000Z

311

Evaluation of Hardware and Procedures for Astronaut Assembly and Repair of Large Precision Reflectors  

Science Conference Proceedings (OSTI)

A detailed procedure is presented that enables astronauts in extravehicular activity (EVA) to efficiently assemble and repair large (i.e., greater than 10m-diameter) segmented reflectors, supported by a truss, for space-based optical or radio-frequency ...

Lake Mark S.; Jr Walter L. Heard; Watson Judith J.; Collins Timothy J.

2000-08-01T23:59:59.000Z

312

Overview of NCHRP Design Guideline for EPS-Block Geofoam in Slope Stabilization and Repair  

E-Print Network (OSTI)

Manhattan College Bronx, New York 10471 Tel: (718) 826-7177 E-mail: john.horvath@manhattan.edu Dov and repair applications based on the results of National Cooperative Highway Research Program (NCHRP) Project was performed under NCHRP Project 24-11(01) and produced a design guideline for use of EPS blocks in stand

Horvath, John S.

313

Higher-order discrete variational problems with constraints  

E-Print Network (OSTI)

An interesting family of geometric integrators for Lagrangian systems can be defined using discretizations of the Hamilton's principle of critical action. This family of geometric integrators is called variational integrators. In this paper, we derive new variational integrators for higher-order lagrangian mechanical system subjected to higher-order constraints. From the discretization of the variational principles, we show that our methods are automatically symplectic and, in consequence, with a very good energy behavior. Additionally, the symmetries of the discrete Lagrangian imply that momenta is conserved by the integrator. Moreover, we extend our construction to variational integrators where the lagrangian is explicitly time-dependent. Finally, some motivating applications of higher-order problems are considered; in particular, optimal control problems for explicitly time-dependent underactuated systems and an interpolation problem on Riemannian manifolds.

Leonardo Colombo; David Martín de Diego; Marcela Zuccalli

2013-06-03T23:59:59.000Z

314

Physics problems of thermonuclear reactors  

SciTech Connect

From topical conference on energy; Philadelphia, Pennsylvania, USA (Nov 1973). A problem common to all controlled fusion reactors is that of the burning deuterium --tritium fuel under conditions of plasma confinement which approach the ideal limit as nearly as possible. After ignitlon, the balance between alpha- particle energy deposition and plasma losses (radiation plus thermal and particle diffusion) determines the stability or instability of the burn in toroidal systems. Tokamak systems are described both with unstable, injection-regulated burn cycles and stabilized steady-state burn conditions. In the theta-pinch reactor an unstable burn occurs, some, what regulated by high-beta plasma expansion, which is quenched by a programmed plasma decompression. The plasma expansion during the constant-pressure burn provides direct'' conversion of plasma thermonuclear heat to electrical output, in addition to the electrical power derived from the neutron energy through conventional thermal conversion equipment. The open-ended mirror reactor is characterized by a direct conversion system for recovering end-loss plasma energy and converting it to electrical energy for reinjection into the plasma. This allows a favorable reactor energy balance and an amplification factor Q (= thermonuclear energy output/injected plasma energy) which is compatible with classical collisional losses. For the three reactor types considered the ramifications of burn and confinement conditions for reactor configuration, energy balance, economy, fuel handling, materials problems, and environmentalradiological factors are considered. (auth)

Ribe, F.L.

1974-01-01T23:59:59.000Z

315

The ANgel Problem, Positional Games, . . .  

E-Print Network (OSTI)

This thesis is about combinatorial games—mostly. It is also about graphs, directed graphs and hypergraphs, to a large extent; and it deals with the complexity of certain computational problems from these two areas. We study three different problems that share several of the above aspects, yet, they form three individual subjects and so we treat them independently in three self-contained chapters: The angel-devil game. In the first chapter, we present improved strategies for an infinite game played on an infinite chess board, which has been introduced by Berlekamp, Conway, and Guy [8]. The angel, a chess person who jumps from square to square, tries to escape his opponent, the devil, who intends to strand the angel by placing obstacles on the board. The open question about this game is, whether some angel who is allowed to make sufficiently large but bounded steps in each move, will be able to escape forever. Conway [11] has shown that certain quite natural escape attempts are bound to fail.

Martin Kutz

2004-01-01T23:59:59.000Z

316

Virtual Human Problem Solving Environments  

SciTech Connect

Abstract. Interest in complex integrated digital or virtual human modeling has seen a significant increase over the last decade. Coincident with that increased interest, Oak Ridge National Laboratory (ORNL) initiated the development of a human simulation tool, the Virtual Human. The Virtual Human includes a problem-solving environment (PSE) for implementing the integration of physiological models in different programming languages and connecting physiological function to anatomy. The Virtual Human PSE (VHPSE) provides the computational framework with which to develop the concept of a "Virtual Human." Supporting the framework is a data definition for modeling parameters, PhysioML, a Virtual Human Database (VHDB), and a Web-based graphical user interface (GUI) developed using Java. Following description of the VHPSE, we discuss four example implementations of models within the framework. Further expansion of a human modeling environment was carried out in the Defense Advanced Research Projects Agency Virtual Soldier Project. SCIRun served as the Virtual Soldier problem solving environment (VSPSE). We review and compare specific developments in these projects that have significant potential for the future of Virtual Human modeling and simulation. We conclude with an evaluation of areas of future work that will provide important extensions to the VHPSE and VSPSE and make possible a fully-integrated environment for human anatomical and physiological modeling: the Virtual Human.

Ward, Richard C [ORNL; Pouchard, Line Catherine [ORNL; Munro, Nancy B [ORNL; Fischer, Sarah Kathleen [ORNL

2008-01-01T23:59:59.000Z

317

ACOUSTICAL IMAGING AND MECHANICAL PROPERTIES OF SOFT ROCK AND MARINE SEDIMENTS  

SciTech Connect

The oil and gas industry has encountered significant problems in the production of oil and gas from weak rocks (such as chalks and limestones) and from unconsolidated sand formations. Problems include subsidence, compaction, sand production, and catastrophic shallow water sand flows during deep water drilling. Together these cost the petroleum industry hundreds of millions of dollars annually. The goals of this first quarterly report is to document the progress on the project to provide data on the acoustic imaging and mechanical properties of soft rock and marine sediments. The project is intended to determine the geophysical (acoustic velocities) rock properties of weak, poorly cemented rocks and unconsolidated sands. In some cases these weak formations can create problems for reservoir engineers. For example, it cost Phillips Petroleum 1 billion dollars to repair of offshore production facilities damaged during the unexpected subsidence and compaction of the Ekofisk Field in the North Sea (Sulak 1991). Another example is the problem of shallow water flows (SWF) occurring in sands just below the seafloor encountered during deep water drilling operations. In these cases the unconsolidated sands uncontrollably flow up around the annulus of the borehole resulting in loss of the drill casing. The $150 million dollar loss of the Ursa development project in the U.S. Gulf Coast resulted from an uncontrolled SWF (Furlow 1998a,b; 1999a,b). The first three tasks outlined in the work plan are: (1) obtain rock samples, (2) construct new acoustic platens, (3) calibrate and test the equipment. These have been completed as scheduled. Rock Mechanics Institute researchers at the University of Oklahoma have obtained eight different types of samples for the experimental program. These include: (a) Danian Chalk, (b) Cordoba Cream Limestone, (c) Indiana Limestone, (d) Ekofisk Chalk, (e) Oil Creek Sandstone, (f) unconsolidated Oil Creek sand, and (g) unconsolidated Brazos river sand. These weak rocks and sands are intended to represent analogs to the formations that present oil and gas engineers with problems during oil and gas production and drilling operations. A series of new axial acoustic sensors have been constructed (and tested) to allow measurement of compressional and shear wave velocities during high pressure triaxial tests on these weak rock and sand samples. In addition, equipment to be utilized over the next 18 months of the project have tested and calibrated. These include the load frames, triaxial pressure cells, pressure sensors, load cells, extensometers, and oscilloscopes have been calibrated and tested. The multichannel acoustic emission and acoustic pulse transmission systems have also been tested. Graduate research assistant, research faculty, and the laboratory technician have begun Tasks 4 and 5 which involve preparing the sand samples and rock samples for testing. The construction of the lateral acoustic sensors has also been started during this quarter as outlined in the project timeline. With the equipment having been tested and calibrated, and the samples now being prepared, the experiments are on schedule to be started in April, 2001.

Thurman E. Scott, Jr., Ph.D.; Musharraf Zaman, Ph.D.; Younane Abousleiman, Ph.D.

2001-04-01T23:59:59.000Z

318

NSLS Mechanical Tech  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanical Tech Mechanical Tech The Mechanical Technician group is supervised by Robert Scheuerer and consists of Mechanical Technicians with fabrication/machining, assembly, installation, and alignment/surveying skills. This group also serves as an interface to Central Fabrication Services when more complex or larger fabrication efforts are needed. The Mechanical Tech group is responsible for fabricating, installing, aligning, and troubleshooting the mechanical hardware used on NSLS and SDL accelerators, front ends, and User beamlines, often starting solely from Mechanical Design group drawings or CAD files. The Mechanical Tech Group is responsible for the fabrication, assembly and installation of components at the NSLS. These components include all mechanical assemblies and RF cavities. Another part of their job is to

319

Studies of Nonlinear Problems, I  

NLE Websites -- All DOE Office Websites (Extended Search)

. . . ~0s ALAMOS SCIENTIFIC LABORATORY of the UNIVERSITY OF CALIFORNIA ' . c' . .: . Report written: May 1955 Report distributed: LA-1940 h .1 STUDIES OF NONLINEAR PROBLEMS. I . - 4 . . . ._~ Work done by: E. Fermi J. Pasta S. Ulam M. Tsingou PHYSICS Report written by: E. Fermi J. Pasta S. Ulam DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available document. original . - . * * , . ' ABSTRACT " .*. . A one-dimensional dynamical system of 64 particles with forces be- . . . tween neighbors containing nonlinear terms has been studied on the Los Alamos computer MANIAC I. The nonlinear terms considered are quadratic, cubic, and broken linear types. The results are analyzed into Fourier

320

The 3He Supply Problem  

Science Conference Proceedings (OSTI)

One of the main uses for 3He is in gas proportional counters for neutron detection. Radiation portal monitors deployed for homeland security and non-proliferation use such detectors. Other uses of 3He are for research detectors, commercial instruments, well logging detectors, dilution refrigerators, for targets or cooling in nuclear research, and for basic research in condensed matter physics. The US supply of 3He comes almost entirely from the decay of tritium used in nuclear weapons by the US and Russia. A few other countries contribute a small amount to the world’s 3He supply. Due to the large increase in use of 3He for homeland security, the supply has dwindled, and can no longer meet the demand. This white paper reviews the problems of supply, utilization, and alternatives.

Kouzes, Richard T.

2009-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

The Department of Mechanical Engineering --Engineering Mechanics  

E-Print Network (OSTI)

, Missile, Research, Development and Engineering Directorate's Propulsion Iaborato'. Ills primaly areas of research are in numerical combustion, and the thermal and mechanical aging ofnitrate esterpropellants decomposition and combustion. Stabilizers are added to the propellants to neutralize the decomposition products

Endres. William J.

322

Compliant mechanism learning toolkit  

E-Print Network (OSTI)

This thesis concerns a toolkit designed to assist in learning the behavior of complaint mechanisms. In the design of complaint mechanisms, increasingly complicated designs behave in ways that are harder to intuitively ...

Allard, Nicholas (Nicholas A.)

2006-01-01T23:59:59.000Z

323

QUICK QUANTUM MECHANICS ---Introduction ---  

E-Print Network (OSTI)

QUICK QUANTUM MECHANICS --- Introduction --- The following notes are intended to be a supplement to your study of Liboff's ``Introductory Quantum Mechanics.'' They are not an alternative! My purpose here of Classical Mechanics After Newton found his equations of motion, physicists knew they would have to wait

Jackson, Andrew D.

324

Nikon Instruments Inc. | Resource Center -Research Papers -New insights into DNA repair http://www.nikoninstruments.com/Resource-Center/Research-Papers/New-insights-into-DNA-repair[4/10/2012 10:42:30 AM  

E-Print Network (OSTI)

, such as exposure to UV light, other forms of radiation, and certain environmental chemicals. DNA repair processes was performed using an Eclipse TE2000-U inverted microscope with a total internal reflection fluorescence (TIRF

Kowalczykowski, Stephen C.

325

Multigrid Methods for Elliptic Problems: A Review  

Science Conference Proceedings (OSTI)

Multigrid methods solve a large class of problems very efficiently. They work by approximating a problem on multiple overlapping grids with widely varying mesh sizes and cycling between thew approximations, using relaxation to reduce the error on ...

Scott R. Fulton; Paul E. Ciesielski; Wayne H. Schubert

1986-05-01T23:59:59.000Z

326

Competitive solutions for online financial problems  

Science Conference Proceedings (OSTI)

This article surveys results concerning online algorihtms for solving problems related to the management of money and other assets. In particular, the survey focucus us search, replacement, and portfolio selection problems

Ran El-Yaniv

1998-03-01T23:59:59.000Z

327

Approximation algorithms for stochastic scheduling problems  

E-Print Network (OSTI)

In this dissertation we study a broad class of stochastic scheduling problems characterized by the presence of hard deadline constraints. The input to such a problem is a set of jobs, each with an associated value, processing ...

Dean, Brian C. (Brian Christopher), 1975-

2005-01-01T23:59:59.000Z

328

Field Guide: Bearing Damage Mechanisms  

Science Conference Proceedings (OSTI)

Electric Power Research Institute (EPRI) report 1021780, Manual of Bearing Failures and Repair in Power Plant Rotating Equipment, 2011 Update, is a comprehensive document on the subject of fluid film bearing damage modes. This field guide provides a pocket reference based upon the content of that report. ...

2012-11-06T23:59:59.000Z

329

Fermi and the ergodic problem Giovanni Gallavotti  

E-Print Network (OSTI)

the esoteric (quasi) ergodic problem. Consider- ing a `{degrees of freedom system, ` > 2, with Hamilto- nian H

Roma "La Sapienza", Università di

330

HYDRAULIC SERVO CONTROL MECHANISM  

DOE Patents (OSTI)

A hydraulic servo control mechanism of compact construction and low fluid requirements is described. The mechanism consists of a main hydraulic piston, comprising the drive output, which is connected mechanically for feedback purposes to a servo control piston. A control sleeve having control slots for the system encloses the servo piston, which acts to cover or uncover the slots as a means of controlling the operation of the system. This operation permits only a small amount of fluid to regulate the operation of the mechanism, which, as a result, is compact and relatively light. This mechanism is particuiarly adaptable to the drive and control of control rods in nuclear reactors. (auth)

Hussey, R.B.; Gottsche, M.J. Jr.

1963-09-17T23:59:59.000Z

331

Quantum Algorithm to Solve Satisfiability Problems  

E-Print Network (OSTI)

A new quantum algorithm is proposed to solve Satisfiability(SAT) problems by taking advantage of non-unitary transformation in ground state quantum computer. The energy gap scale of the ground state quantum computer is analyzed for 3-bit Exact Cover problems. The time cost of this algorithm on general SAT problems is discussed.

Wenjin Mao

2004-11-29T23:59:59.000Z

332

Approximation of Bayesian Inverse Problems for PDEs  

Science Conference Proceedings (OSTI)

Inverse problems are often ill posed, with solutions that depend sensitively on data. In any numerical approach to the solution of such problems, regularization of some form is needed to counteract the resulting instability. This paper is based on an ... Keywords: Bayesian, Markov chain-Monte Carlo, Stokes flow, data assimilation, inverse problem

S. L. Cotter; M. Dashti; A. M. Stuart

2010-04-01T23:59:59.000Z

333

1 July 1996 `The Hard Problem'  

E-Print Network (OSTI)

1 July 1996 Turning `The Hard Problem' Upside Down & Sideways Piet Hut Roger N. Shepard School. As a first option, we reconsider the `hard problem' of the relation between conscious experience and the physical world by thus turning that problem upside down. We also consider a second option: turning the hard

Hut, Piet

334

PROBLEMS OF FORECAST1 Dmitry KUCHARAVY  

E-Print Network (OSTI)

1 PROBLEMS OF FORECAST1 Dmitry KUCHARAVY dmitry.kucharavy@insa-strasbourg.fr Roland DE GUIO roland for the purpose of Innovative Design. First, a brief analysis of problems for existing forecasting methods of the forecast errors. Second, using a contradiction analysis, a set of problems related to technology forecast

Paris-Sud XI, Université de

335

Dynamical probability, particle trajectories and completion of traditional quantum mechanics  

E-Print Network (OSTI)

Maintaining the position that the wave function $\\psi$ provides a complete description of state, the traditional formalism of quantum mechanics is augmented by introducing continuous trajectories for particles which are sample paths of a stochastic process determined (including the underlying probability space) by $\\psi$. In the resulting formalism, problems relating to measurements and objective reality are solved as in Bohmian mechanics (without sharing its weak points). The pitfalls of Nelson's stochastic mechanics are also avoided.

Tulsi Dass

2005-05-25T23:59:59.000Z

336

Mechanical Seal Assembly  

DOE Patents (OSTI)

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Kotlyar, Oleg M.

1999-06-18T23:59:59.000Z

337

Mechanical seal assembly  

DOE Patents (OSTI)

An improved mechanical seal assembly is provided for sealing rotating shafts with respect to their shaft housings, wherein the rotating shafts are subject to substantial axial vibrations. The mechanical seal assembly generally includes a rotating sealing ring fixed to the shaft, a non-rotating sealing ring adjacent to and in close contact with the rotating sealing ring for forming an annular seal about the shaft, and a mechanical diode element that applies a biasing force to the non-rotating sealing ring by means of hemispherical joint. The alignment of the mechanical diode with respect to the sealing rings is maintained by a series of linear bearings positioned axially along a desired length of the mechanical diode. Alternative embodiments include mechanical or hydraulic amplification components for amplifying axial displacement of the non-rotating sealing ring and transferring it to the mechanical diode.

Kotlyar, Oleg M. (Salt Lake City, UT)

2001-01-01T23:59:59.000Z

338

A Key Step in Repairing DNA Double-Strand Breaks | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

X-ray Rainbow X-ray Rainbow An Insulating Breakthrough Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed A Key Step in Repairing DNA Double-Strand Breaks JANUARY 10, 2007 Bookmark and Share The atomic structure of the protein 53BP1 identified by Mayo researchers. (Courtesy: Mayo Clinic) A team of Mayo Clinic researchers has uncovered a key step in the molecular pathway of repairing DNA double-strand breaks. The studies were carried out using the 19-ID beamline (SBC-CAT) at the Advanced Photon Source (APS, Argonne) and the X12-C beamline at the National Synchrotron Light Source (NSLS, Brookhaven National Laboratory). Both the APS and the NSLS are funded by the U.S. Department of Energy's Office of Basic Energy

339

Gene Expression Pathways Activated and Repair of DNA of Double Strand  

NLE Websites -- All DOE Office Websites (Extended Search)

Pathways Activated and Repair of DNA of Double Strand Pathways Activated and Repair of DNA of Double Strand Breaks (DSBs) Following Low Dose Ionizing Radiation in Human Bronchial Epithelial Cells (HBECs) With and Without Defined Premalignant Oncogenic Changes John Minna University of Texas Southwestern Medical Center at Dallas Abstract We want to determine the effect of low dose ionizing radiation on the molecular progression of lung epithelial cells towards lung cancer. Our endpoints are focused on specific molecular and cellular changes known to be associated with lung cancer development and quantitating those changes as a function of low dose ionizing radiation. We use immortalized human bronchial epithelial cells (HBECs) developed from >40 individuals (including those from current, former, and never smokers, males, females,

340

Connections Between the TCR Proteins XPG and CSB, Repair of Oxidative DNA  

NLE Websites -- All DOE Office Websites (Extended Search)

Connections Between the TCR Proteins XPG and CSB, Repair of Oxidative DNA Connections Between the TCR Proteins XPG and CSB, Repair of Oxidative DNA Base Damage, and the Radio-Adaptive Response Helen Budworth, Brett Haltiwanger, Altaf Sarker, Torsten Grösser, Björn Rydberg, and Priscilla K. Cooper* Life Sciences Division, MailStop 74-157, Lawrence Berkeley National Laboratory, Berkeley, CA 94720; *Corresponding author A key question that is central to accurately assessing human health risks from environmentally relevant low level (low dose, low dose rate) exposures to ionizing radiation is whether cellular responses measured at the higher doses for which there are strong epidemiological health data and the high doses commonly used in laboratory experiments extrapolate in a linear fashion to low doses. Recent data suggest that they may not. For example, low-dose hypersensitivity for

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Low Dose Radiation Research Program: Checkpoint Responses and Repair of a  

NLE Websites -- All DOE Office Websites (Extended Search)

Checkpoint Responses and Repair of a Broken Chromosome in Budding Checkpoint Responses and Repair of a Broken Chromosome in Budding Yeast. Authors: André Walther, Mreshwar B. Vaze, Anna Malkova, Grzegorz Ira, Xuan Wang, Jung-Ae Kim, Neal Sugawara, James E. Haber Brandeis University, Waltham, Massachusetts We have studied how yeast cells respond to the creation of a single double-strand break (DSB) by using a site-specific endonuclease to create one (or more) DSBs. In collaboration with R. Schroff, M. Licheten and W. Bonner (NIH) we have shown that a single DSB rapidly becomes associated with histone H2AX-phosphorylation (y-H2AX) covering a distance of about 25 kb on either side of the DSB. The drop-off in phosphorylation is not attributable to specific boundary sequences. y-H2AX can be phosphorylated by either ATR (Mec1) or ATM (Tel1) protein kinases. A mutation that removes

342

Standard practice for infrared flash thermography of composite panels and repair patches used in aerospace applications  

E-Print Network (OSTI)

1.1 This practice describes a procedure for detecting subsurface flaws in composite panels and repair patches using Flash Thermography (FT), in which an infrared (IR) camera is used to detect anomalous cooling behavior of a sample surface after it has been heated with a spatially uniform light pulse from a flash lamp array. 1.2 This practice describes established FT test methods that are currently used by industry, and have demonstrated utility in quality assurance of composite structures during post-manufacturing and in-service examinations. 1.3 This practice has utility for testing of polymer composite panels and repair patches containing, but not limited to, bismaleimide, epoxy, phenolic, poly(amide imide), polybenzimidazole, polyester (thermosetting and thermoplastic), poly(ether ether ketone), poly(ether imide), polyimide (thermosetting and thermoplastic), poly(phenylene sulfide), or polysulfone matrices; and alumina, aramid, boron, carbon, glass, quartz, or silicon carbide fibers. Typical as-fabricate...

American Society for Testing and Materials. Philadelphia

2007-01-01T23:59:59.000Z

343

Subterranean barriers, methods, and apparatuses for forming, inspecting, selectively heating, and repairing same  

DOE Patents (OSTI)

A subterranean barrier and method for forming same are disclosed, the barrier including a plurality of casing strings wherein at least one casing string of the plurality of casing strings may be affixed to at least another adjacent casing string of the plurality of casing strings through at least one weld, at least one adhesive joint, or both. A method and system for nondestructively inspecting a subterranean barrier is disclosed. For instance, a radiographic signal may be emitted from within a casing string toward an adjacent casing string and the radiographic signal may be detected from within the adjacent casing string. A method of repairing a barrier including removing at least a portion of a casing string and welding a repair element within the casing string is disclosed. A method of selectively heating at least one casing string forming at least a portion of a subterranean barrier is disclosed.

Nickelson, Reva A. (Shelley, ID); Sloan, Paul A. (Rigby, ID); Richardson, John G. (Idaho Falls, ID); Walsh, Stephanie (Idaho Falls, ID); Kostelnik, Kevin M. (Idaho, ID)

2009-04-07T23:59:59.000Z

344

Weld Repair of a Stamped Pressure Vessel in a Radiologically Controlled Zone  

Science Conference Proceedings (OSTI)

In September 2012 an ASME B&PVC Section VIII stamped pressure vessel located at the DOE Hanford Site Effluent Treatment Facility (ETF) developed a through-wall leak. The vessel, a steam/brine heat exchanger, operated in a radiologically controlled zone (by the CH2MHill PRC or CHPRC), had been in service for approximately 17 years. The heat exchanger is part of a single train evaporator process and its failure caused the entire system to be shut down, significantly impacting facility operations. This paper describes the activities associated with failure characterization, technical decision making/planning for repair by welding, logistical challenges associated with performing work in a radiologically controlled zone, performing the repair, and administrative considerations related to ASME code requirements.

Cannell, Gary L. [Fluor Enterprises, Inc.; Huth, Ralph J. [CH2MHill Plateau Remediation Company; Hallum, Randall T. [Fluor Government Group

2013-08-26T23:59:59.000Z

345

Role of Cell Cycle Regulation and MLH1, A Key DNA Mismatch Repair Protein, In Adaptive Survival Responses. Final Report  

SciTech Connect

Due to several interesting findings on both adaptive survival responses (ASRs) and DNA mismatch repair (MMR), this grant was separated into two discrete Specific Aim sets (each with their own discrete hypotheses). The described experiments were simultaneously performed.

David A. Boothman

1999-08-11T23:59:59.000Z

346

To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair Dec. 1-20, 2006  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

From: ecchimento@comcast.net [mailto:ecchimento@comcast.net] Sent: Monday, January 29, 2007 6:28 PM To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Larry, Regarding the planned line outage, scheduled for Feb. 20 through Mar. 6, I am requesting that the residents near the plant be moved for the duration of the outage to protect their health. Would you include this comment also in the ongoing recorded discussion? Thank you. Elizabeth

347

Precracked RC T-beams Repaired in Shear with Externally Bonded CFRP Sheets  

E-Print Network (OSTI)

, strengthening and repair of existing structures, advanced numerical analyses, glass fiber reinforced polymer pipelines and sustainable concrete. Chris Morley is a former Senior Lecturer in Concrete Structures at Cambridge University, UK. He has always been... effective since only a fairly short bonded length is available for force transfer. Another explanation could be that the “deeper” beams had more CFRP area bridging a shear crack compared to the “shallower” beams. Shear force-deflection relationship...

Dirar, Samir; Lees, Janet M.; Morley, Chris T.

2012-03-01T23:59:59.000Z

348

Computer Based Training (CBT) Buried Pipe Condition Assessment and Repair, Version 1.0  

Science Conference Proceedings (OSTI)

The purpose of this training module is to provide an understanding of the inspection of buried piping. Course 1 of the course covers initial direct condition assessment of excavated buried pipe. Course 2 covers buried pipe coating repairs and final as-left inspections of piping. The CBT includes graphics, interactive features, and review questions to help the student better understand the subject. Windows XP, Vista, 7

2011-11-23T23:59:59.000Z

349

Nondestructive Evaluation: Risk-Informed In-Service Repair and Replacement: Draft Methodology  

Science Conference Proceedings (OSTI)

Code Case N-660, Revision 0, "Risk-Informed Safety Classification for Use in Risk-Informed Repair/Replacement Activities," was published by ASME and was developed to expand the breadth of risk-informed Section XI requirements to pressure boundary components. This report provides a generic draft methodology and technical basis for revisions to N-660 for Class 2 and 3 systems based on lessons learned from pilot application to Arkansas Nuclear One (ANO), Unit 2.

2009-12-23T23:59:59.000Z

350

Review of Weld Repair Options for Grade 91, Part 2: Damage Development and Distribution  

Science Conference Proceedings (OSTI)

This report reviews the likely creep damage distributions in weld repairs in Grade 91 steel. Information is provided in terms of the various weld metals that may be used, including nickel-based, matching P91 (B9), and standard P9 (B8) weld metals. The different damage distributions for each type, with associated implications for nondestructive evaluation, are discussed. In particular, the limitations of using surface ...

2013-06-20T23:59:59.000Z

351

Black Hole Thermodynamics and Statistical Mechanics  

E-Print Network (OSTI)

We have known for more than thirty years that black holes behave as thermodynamic systems, radiating as black bodies with characteristic temperatures and entropies. This behavior is not only interesting in its own right; it could also, through a statistical mechanical description, cast light on some of the deep problems of quantizing gravity. In these lectures, I review what we currently know about black hole thermodynamics and statistical mechanics, suggest a rather speculative "universal" characterization of the underlying states, and describe some key open questions.

Steven Carlip

2008-07-28T23:59:59.000Z

352

One-dimensional Gromov minimal filling problem  

Science Conference Proceedings (OSTI)

The paper is devoted to a new branch in the theory of one-dimensional variational problems with branching extremals, the investigation of one-dimensional minimal fillings introduced by the authors. On the one hand, this problem is a one-dimensional version of a generalization of Gromov's minimal fillings problem to the case of stratified manifolds. On the other hand, this problem is interesting in itself and also can be considered as a generalization of another classical problem, the Steiner problem on the construction of a shortest network connecting a given set of terminals. Besides the statement of the problem, we discuss several properties of the minimal fillings and state several conjectures. Bibliography: 38 titles.

Ivanov, Alexandr O; Tuzhilin, Alexey A

2012-05-31T23:59:59.000Z

353

Comparison of American Petroleum Institute 579/American Society of Mechanical Engineers FFS1 with EPRI Life Assessment Guidelines  

Science Conference Proceedings (OSTI)

The American Society of Mechanical Engineers (ASME) governs the design and construction of power boilers and piping systems in the United States and many other countries. The ASME rules generally cover only the design and construction of these components, whereas rules for maintenance, repair, and life assessment are not addressed. Recently, ASME has been developing guidelines for post-construction activities, including damage assessment and life prediction. The Electric Power Research Institute (EPRI) h...

2010-08-31T23:59:59.000Z

354

DNA repair in mammalian cells exposed to combinations of carcinogenic agents. [uv radiation; AAAF; 4-NQO; DMBA-epoxide; ICR-170  

SciTech Connect

Cells defective in one or more aspects of repair are killed and often mutagenized more readily than normal cells by DNA damaging agents, and humans whose cells are deficient in repair are at an increased carcinogenic risk compared to normal individuals. The excision repair of uv induced pyrimidine dimers is a well studied system, but the details of the steps in this repair system are far from being understood in human cells. We know that there are a number of chemicals that mimic uv in that normal human cells repair DNA damage from both these agents and from uv by a long patch excision repair system, and that xeroderma pigmentosum cells defective in repair of uv are also defective in the repair of damage from these chemicals. The chemicals we have investigated are AAAF, 4-NQO, DMBA-epoxide, and ICR-170. We describe experiments, using several techniques, in which DNA excision repair is measured after treatment of various human cell strains with combinations of uv and these agents. If two agents have a common rate limiting step then, at doses high enough to saturate the repair system, one would expect the observed repair after a treatment with a combination of agents to be equal to that from one agent alone. Such is not the case for normal human or excision-deficient XP cells. In the former repair is additive and in the latter repair is usually appreciably less than that observed with either agent alone. Models that attempt to explain these surprising results involve complexes of enzymes and cofactors.

Setlow, R.B.; Ahmed, F.E.

1979-01-01T23:59:59.000Z

355

Mechanics of Funding matrix  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

FUNDING MECHANISMS FUNDING MECHANISMS Funding Mechanism Advantages Disadvantages Comments 1. From Doe to regional organizations * * Facilitates a broad, regional approach to planning and implementation that enhances consistency and uniformity * * Especially beneficial for new programs where early planning is needed * * Simplifies communication for DOE to have only one point of contact for information and discussion * * Cooperative agreement mechanism has proven relatively simple to administer * * Approach would require modification for Tribes * * Would also require that funding be provided to individual States to enable them to participate in the process, since planning authority and responsibility rests with the individual State * * Differs from OCRWM approach to 180(c) funding * * Introduces another layer of

356

Mechanical Behavior II  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... Impact of Cooling Rate on Low Silver Sn-Ag-Cu Solder Interconnect Board Level Mechanical Shock and Thermal Cycling Performance: ...

357

Structures and Mechanical Properties  

Science Conference Proceedings (OSTI)

Mar 7, 2013... Refractory High-entropy Alloy: Chien-Chang Juan1; Jien-Wei Yeh1; ... The main wear mechanism was adhesive wear in deionized water, ...

358

Mechanical Behavior I  

Science Conference Proceedings (OSTI)

Mar 5, 2013... (IMC) is essential for understandingthe mechanical behavior of the ... Reliability and by the SHaRE User Facility, Scientific User Facilities ...

359

Constrained Graph Optimization: Interdiction and Preservation Problems  

SciTech Connect

The maximum flow, shortest path, and maximum matching problems are a set of basic graph problems that are critical in theoretical computer science and applications. Constrained graph optimization, a variation of these basic graph problems involving modification of the underlying graph, is equally important but sometimes significantly harder. In particular, one can explore these optimization problems with additional cost constraints. In the preservation case, the optimizer has a budget to preserve vertices or edges of a graph, preventing them from being deleted. The optimizer wants to find the best set of preserved edges/vertices in which the cost constraints are satisfied and the basic graph problems are optimized. For example, in shortest path preservation, the optimizer wants to find a set of edges/vertices within which the shortest path between two predetermined points is smallest. In interdiction problems, one deletes vertices or edges from the graph with a particular cost in order to impede the basic graph problems as much as possible (for example, delete edges/vertices to maximize the shortest path between two predetermined vertices). Applications of preservation problems include optimal road maintenance, power grid maintenance, and job scheduling, while interdiction problems are related to drug trafficking prevention, network stability assessment, and counterterrorism. Computational hardness results are presented, along with heuristic methods for approximating solutions to the matching interdiction problem. Also, efficient algorithms are presented for special cases of graphs, including on planar graphs. The graphs in many of the listed applications are planar, so these algorithms have important practical implications.

Schild, Aaron V [Los Alamos National Laboratory

2012-07-30T23:59:59.000Z

360

Perfect transmission scattering as a PT-symmetric spectral problem  

E-Print Network (OSTI)

We establish that a perfect-transmission scattering problem can be described by a class of parity and time reversal symmetric operators and hereby we provide a scenario for understanding and implementing the corresponding quasi-Hermitian quantum mechanical framework from the physical viewpoint. One of the most interesting features of the analysis is that the complex eigenvalues of the underlying non-Hermitian problem, associated with a reflectionless scattering system, lead to the loss of perfect-transmission energies as the parameters characterizing the scattering potential are varied. On the other hand, the scattering data can serve to describe the spectrum of a large class of Schroedinger operators with complex Robin boundary conditions.

H. Hernandez-Coronado; D. Krejcirik; P. Siegl

2010-11-18T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Assessment of environmental and safety problems in hydrogen energy systems  

DOE Green Energy (OSTI)

Numerous suggestions have been made for the use of hydrogen as a portable or transportable fuel. To effect safely an expanded use of hydrogen requires fundamental knowledge of the appropriate safety problems as well as mechanisms to ensure the proper design of equipment and techniques used in its storage, shipment, and use. Most likely methods of shipment consist of an extension of existing technology; namely, gas transmission by pipeline and bulk transportation of hydrogen as a cryogenic liquid. While these are well developed, safety and technological problems still exist and include such issues as dispersion of hydrogen releases, behavior of hydrogen on combustion, and hydrogen embrittlement. Safe transportation and handling of hydrogen can be enhanced by uniformity of codes and regulations. Hydrogen use as a fuel is not totally benign from an environmental standpoint; however, the combination of production and end use is generally more acceptable for hydrogen than for alternative fuels.

Edeskuty, F.J.; Bartlit, J.R.; Carlson, R.V.

1979-01-01T23:59:59.000Z

362

Consciousness in Robots: The Hard Problem and Some Less Hard Problems  

E-Print Network (OSTI)

Consciousness in Robots: The Hard Problem and Some Less Hard Problems B. J. MacLennan Department it is also important. Finally we explore the Hard Problem for robots (i.e., whether they can experience sub, intentional- ity, evolutionary psychology, artificial life, autonomous robots, the hard problem I

Tennessee, University of

363

Consciousness in Robots: The Hard Problem and Some Less Hard Problems  

E-Print Network (OSTI)

1 Consciousness in Robots: The Hard Problem and Some Less Hard Problems (Extended Version intrinsic intentionality from consciousness, but argue it is also important. Fi- nally we explore the Hard using "the Hard Problem" to refer to the principal scientific problem of consciousness, which

Tennessee, University of

364

Probable Inference and Quantum Mechanics  

SciTech Connect

In its current very successful interpretation the quantum theory is fundamentally statistical in nature. Although commonly viewed as a probability amplitude whose (complex) square is a probability, the wavefunction or state vector continues to defy consensus as to its exact meaning, primarily because it is not a physical observable. Rather than approach this problem directly, it is suggested that it is first necessary to clarify the precise role of probability theory in quantum mechanics, either as applied to, or as an intrinsic part of the quantum theory. When all is said and done the unsurprising conclusion is that quantum mechanics does not constitute a logic and probability unto itself, but adheres to the long-established rules of classical probability theory while providing a means within itself for calculating the relevant probabilities. In addition, the wavefunction is seen to be a description of the quantum state assigned by an observer based on definite information, such that the same state must be assigned by any other observer based on the same information, in much the same way that probabilities are assigned.

Grandy, W. T. Jr. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82070 (United States)

2009-12-08T23:59:59.000Z

365

Solar mechanics thermal response capabilities.  

DOE Green Energy (OSTI)

In many applications, the thermal response of structures exposed to solar heat loads is of interest. Solar mechanics governing equations were developed and integrated with the Calore thermal response code via user subroutines to provide this computational simulation capability. Solar heat loads are estimated based on the latitude and day of the year. Vector algebra is used to determine the solar loading on each face of a finite element model based on its orientation relative to the sun as the earth rotates. Atmospheric attenuation is accounted for as the optical path length varies from sunrise to sunset. Both direct and diffuse components of solar flux are calculated. In addition, shadowing of structures by other structures can be accounted for. User subroutines were also developed to provide convective and radiative boundary conditions for the diurnal variations in air temperature and effective sky temperature. These temperature boundary conditions are based on available local weather data and depend on latitude and day of the year, consistent with the solar mechanics formulation. These user subroutines, coupled with the Calore three-dimensional thermal response code, provide a complete package for addressing complex thermal problems involving solar heating. The governing equations are documented in sufficient detail to facilitate implementation into other heat transfer codes. Suggestions for improvements to the approach are offered.

Dobranich, Dean D.

2009-07-01T23:59:59.000Z

366

Computational evaluation of two reactor benchmark problems  

E-Print Network (OSTI)

A neutronic evaluation of two reactor benchmark problems was performed. The benchmark problems describe typical PWR uranium and plutonium (mixed oxide) fueled lattices. WIMSd4m, a neutron transport lattice code, was used to evaluate multigroup macroscopic cross sections for various pincell models in each benchmark problem. DEF3D, a multigroup multidimensional diffusion code, was used to evaluate the uranium-fueled lattice benchmark problem of the American Nuclear Society. TWODANT, a multigroup, two-dimensional transport code, was used to evaluate the mixed oxide lattice benchmark problem from the Nuclear Energy Agency. Both benchmark problems yielded results consistent with preliminary results submitted by other participants in the benchmarking exercises. Some suggestions are made to improve future benchmark evaluations.

Cowan, James Anthony

1998-01-01T23:59:59.000Z

367

Mecanica Clasica (Classical Mechanics)  

E-Print Network (OSTI)

First Internet undergraduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

Rosu, H C

1999-01-01T23:59:59.000Z

368

Quantum Mechanics Measurements, Mutually  

E-Print Network (OSTI)

Quantum Mechanics Measurements, Mutually Unbiased Bases and Finite Geometry Or why six is the first) #12;Quantum Mechanics for Dummies Finite dimensional quantum states are represented by trace one,1 -icS1,1[ ] #12;Quantum systems evolve and are measured. The evolution of a quantum system using

Gruner, Daniel S.

369

Hans Bethe and the Global Energy Problems  

E-Print Network (OSTI)

Bethe's view-point on the global energy problems is presented. Bethe claimed that the nuclear power is a necessity in future. Nuclear energetic must be based on breeder reactors. Bethe considered the non-proliferation of nuclear weapons as the main problem of long-range future of nuclear energetics. The solution of this problem he saw in heavy water moderated thermal breeders, using uranium-233, uranium-238 and thorium as a fuel.

Ioffe, B L

2005-01-01T23:59:59.000Z

370

Minimal Achievable Error in the LED problem  

E-Print Network (OSTI)

This paper presents a theoretical model to predict the minimal achievable error, given a noise ratio #, in the LED data set problem. The motivation for developing this theoretical model is to understand and explain some of the results that di#erent systems achieve when they solve the LED problem. Moreover, given a new learning algorithm that solves the LED problem, we can now bound its optimal generalization accuracy.

Xavier Llora; Xavier Llora; David E. Goldberg; David E. Goldberg

2002-01-01T23:59:59.000Z

371

Hans Bethe and the Global Energy Problems  

E-Print Network (OSTI)

Bethe's view-point on the global energy problems is presented. Bethe claimed that the nuclear power is a necessity in future. Nuclear energetic must be based on breeder reactors. Bethe considered the non-proliferation of nuclear weapons as the main problem of long-range future of nuclear energetics. The solution of this problem he saw in heavy water moderated thermal breeders, using uranium-233, uranium-238 and thorium as a fuel.

B. L. Ioffe

2005-07-06T23:59:59.000Z

372

Mechanical code comparator  

DOE Patents (OSTI)

A new class of mechanical code comparators is described which have broad potential for application in safety, surety, and security applications. These devices can be implemented as micro-scale electromechanical systems that isolate a secure or otherwise controlled device until an access code is entered. This access code is converted into a series of mechanical inputs to the mechanical code comparator, which compares the access code to a pre-input combination, entered previously into the mechanical code comparator by an operator at the system security control point. These devices provide extremely high levels of robust security. Being totally mechanical in operation, an access control system properly based on such devices cannot be circumvented by software attack alone.

Peter, Frank J. (Albuquerque, NM); Dalton, Larry J. (Bernalillo, NM); Plummer, David W. (Albuquerque, NM)

2002-01-01T23:59:59.000Z

373

CA Problem is Price - Energy Information Administration  

U.S. Energy Information Administration (EIA)

The basic California problem concerning heavy crude oil is price. With the reported cost of the natural-gas-fueled steam for extracting the crude sometimes being as ...

374

Multi-Standard Quadratic Optimization Problems  

E-Print Network (OSTI)

Abstract. A Standard Quadratic Optimization Problem (StQP) consists ... A multi- standard quadratic optimiza- ..... the two sums in the last row above are identical.

375

The Facility Location Problem with Bernoulli Demands  

E-Print Network (OSTI)

Abstract. In this paper we address a discrete capacitated facility location problem in which ...... The type of instance for FLPBD (1, 2, 3, or 4) as described above.

376

Student's algorithm solves real-world problem  

NLE Websites -- All DOE Office Websites (Extended Search)

how to use powerful computers to analyze, model, and solve real-world problems," Jordan Medlock wins supercomputer challenge with his algorithm that automates counting and...

377

On the Transportation Problem with Market Choice  

E-Print Network (OSTI)

Apr 3, 2013 ... Abstract: We study a variant of the classical transportation problem in which suppliers with limited capacities have a choice of which demands ...

378

Optimization Online - The Freight Train Routing Problem  

E-Print Network (OSTI)

Jul 21, 2013 ... Abstract: We consider the following freight train routing problem (FTRP). Given is a transportation network with fixed routes for passenger trains ...

379

Quantum Condensates in Nuclear Matter: Problems  

E-Print Network (OSTI)

In connection with the contribution "Quantum Condensates in Nuclear Matter" some problems are given to become more familiar with the techniques of many-particle physics.

G. Ropke; D. Zablocki

2010-01-11T23:59:59.000Z

380

MIRPLib: A Maritime Inventory Routing Problem Library  

E-Print Network (OSTI)

Aug 28, 2013 ... Abstract: This paper presents a detailed description of a particular class of deterministic single product maritime inventory routing problems ...

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Brief announcement: Exploring the Consistency Problem Space  

E-Print Network (OSTI)

We study formally the consistency problem, for replicated shared data, in the Action-Constraint framework (ACF). ACF can describe a large range of application semantics and replication protocols, including optimistic and/or partial replication. ACF is used to decompose the consistency problem into simpler sub-problems. Each is easily understood. Existing algorithms from the literature can be explained as combinations of concrete sub-problem implementations. Using ACF, we design a new serialisation algorithm that does not cause aborts and only needs pairwise agreement (not global consensus).

Nishith Krishna; Marc Shapiro; Karthikeyan Bhargavan

2005-01-01T23:59:59.000Z

382

Optimization Online - Stochastic Nash Equilibrium Problems ...  

E-Print Network (OSTI)

May 22, 2009 ... Finally, the model is applied to a stochastic Nash equilibrium problem in the electricity market. Keywords: Stochastic Nash equilibrium, ...

383

The recoverable robust tail assignment problem  

E-Print Network (OSTI)

using column generation in the master and subproblems of the Benders ...... described by (36)-(41) is a network flow problem with one source and multiple sink.

384

Optimization Online - Minimax Robust Unit Commitment Problem ...  

E-Print Network (OSTI)

Oct 19, 2012... Commitment Problem with Demand and Market Price uncertainty ... to energy providers --- consists of finding an energy production plan in ...

385

Integer Solutions to Cutting Stock Problems  

E-Print Network (OSTI)

ting Stock Problem (CSP) that can be described as follows: find the most ... two integer linear programming models for the one-dimensional CSP differing in.

386

Exact Solution of Emerging Quadratic Assignment Problems  

E-Print Network (OSTI)

National Science Foundation under grant No. DMI-. 0400155. .... Process Allocation Problem of Sofianopoulous ([63] and. [64]), the ...... lower bound is tight

387

Structural Mechanics & Solid Mechanics A finite element toolbox to MATLAB  

E-Print Network (OSTI)

Structural Mechanics & Solid Mechanics Department of Mechanics and Materials CALFEM A finite.3 Copyright © 1999 by Structural Mechanics, LTH, Sweden. Printed by JABE Offset, Lund, Sweden. ISRN LUTVDG/TVSM--99/9001--SE (1-265) ISSN 0281-6679 Department of Mechanics and Materials Structural Mechanics #12;The

Ehrhardt, Matthias

388

A symmetrical theory of nonrelativistic quantum mechanics  

E-Print Network (OSTI)

This paper presents a new Symmetrical Theory (ST) of nonrelativistic quantum mechanics which postulates: quantum mechanics is a theory about complete experiments, not particles; a complete experiment is maximally described by a complex transition amplitude density; and this transition amplitude density never collapses. This new ST is compared to the Conventional Theory (CT) of nonrelativistic quantum mechanics for the analysis of a beam-splitter experiment. The ST makes several experimentally testable predictions that differ from the CT, which can be checked using existing technology. The ST also solves one part of the CT measurement problem, and resolves some of the paradoxes of the CT. This nonrelativistic ST is the low energy limit of a relativistic ST presented in an earlier paper \\cite{Heaney1}.

Michael B. Heaney

2013-10-20T23:59:59.000Z

389

A new introductory quantum mechanics curriculum  

E-Print Network (OSTI)

The Institute of Physics New Quantum Curriculum consists of freely available online learning and teaching materials (quantumphysics.iop.org) for a first course in university quantum mechanics starting from two-level systems. This approach immediately immerses students in inherently quantum mechanical aspects by focusing on experiments that have no classical explanation. It allows from the start a discussion of interpretive aspects of quantum mechanics and quantum information theory. This article gives an overview of the resources available at the IOP website. The core text is presented as around 80 articles co-authored by leading experts that are arranged in themes and can be used flexibly to provide a range of alternative approaches. Many of the articles include interactive simulations with accompanying activities and problem sets that can be explored by students to enhance their understanding. Much of the linear algebra needed for this approach is part of the resource. Solutions to activities are available ...

Kohnle, Antje; Browne, Dan; Everitt, Mark; Fomins, Aleksejs; Kok, Pieter; Kulaitis, Gytis; Prokopas, Martynas; Raine, Derek; Swinbank, Elizabeth

2013-01-01T23:59:59.000Z

390

Rotary mechanical latch  

Science Conference Proceedings (OSTI)

A rotary mechanical latch for positive latching and unlatching of a rotary device with a latchable rotating assembly having a latching gear that can be driven to latched and unlatched states by a drive mechanism such as an electric motor. A cam arm affixed to the latching gear interfaces with leading and trailing latch cams affixed to a flange within the drive mechanism. The interaction of the cam arm with leading and trailing latch cams prevents rotation of the rotating assembly by external forces such as those due to vibration or tampering.

Spletzer, Barry L.; Martinez, Michael A.; Marron, Lisa C.

2012-11-13T23:59:59.000Z

391

Electronic door locking mechanism  

DOE Patents (OSTI)

The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch. 6 figs.

Williams, G.L.; Kirby, P.G.

1997-10-21T23:59:59.000Z

392

Electronic door locking mechanism  

SciTech Connect

The invention is a motorized linkage for engaging a thumb piece in a door mechanism. The device has an exterior lock assembly with a small battery cell and combination lock. Proper entry by a user of a security code allows the battery to operate a small motor within the exterior lock assembly. The small motor manipulates a cam-plunger which moves an actuator pin into a thumb piece. The user applies a force on to the thumb piece. This force is transmitted by the thumb piece to a latch engagement mechanism by the actuator pin. The latch engagement mechanism operates the door latch.

Williams, Gary Lin (428 E. Third Ave., Kennewick, WA 99336); Kirby, Patrick Gerald (1010 W. Fifteenth Pl., Kennewick, WA 99337)

1997-01-01T23:59:59.000Z

393

Is quantum mechanics exact?  

SciTech Connect

We formulate physically motivated axioms for a physical theory which for systems with a finite number of degrees of freedom uniquely lead to quantum mechanics as the only nontrivial consistent theory. Complex numbers and the existence of the Planck constant common to all systems arise naturally in this approach. The axioms are divided into two groups covering kinematics and basic measurement theory, respectively. We show that even if the second group of axioms is dropped, there are no deformations of quantum mechanics which preserve the kinematic axioms. Thus, any theory going beyond quantum mechanics must represent a radical departure from the usual a priori assumptions about the laws of nature.

Kapustin, Anton [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States)

2013-06-15T23:59:59.000Z

394

The inverse scattering problem at fixed energy based on the Marchenko equation for an auxiliary Sturm-Liouville operator  

E-Print Network (OSTI)

A new approach is proposed to the solution of the quantum mechanical inverse scattering problem at fixed energy. The method relates the fixed energy phase shifts to those arising in an auxiliary Sturm-Liouville problem via the interpolation theory of the Weyl-Titchmarsh m-function. Then a Marchenko equation is solved to obtain the potential.

Palmai, Tamas

2012-01-01T23:59:59.000Z

395

Designing Optimal Spectral Filters for Inverse Problems  

Science Conference Proceedings (OSTI)

Spectral filtering suppresses the amplification of errors when computing solutions to ill-posed inverse problems; however, selecting good regularization parameters is often expensive. In many applications, data are available from calibration experiments. ... Keywords: Bayes risk, Bayesian risk, Tikhonov, Wiener filter, empirical risk, filtering, ill-posed problem, image deblurring, machine learning, optimal design, optimal filtering, regularization, singular value decomposition, stochastic programming

Julianne Chung; Matthias Chung; Dianne P. O'Leary

2011-11-01T23:59:59.000Z

396

A Remark on the Kramers Problem  

E-Print Network (OSTI)

We present new point of view on the old problem, the Kramers problem. The passage from the Fokker-Planck equation to the Smoluchowski equation, including corrections to the Smoluchowski current, is treated through an asymptotic expansion of the solution of the stochastic dynamical equations. The case of an extremely weak force of friction is also discussed

A. Samoletov

2003-11-10T23:59:59.000Z

397

A Remark on the Kramers Problem  

E-Print Network (OSTI)

We present new point of view on the old problem, the Kramers problem. The passage from the Fokker-Planck equation to the Smoluchowski equation, including corrections to the Smoluchowski current, is treated through an asymptotic expansion of the solution of the stochastic dynamical equations. The case of an extremely weak force of friction is also discussed

Samoletov, A

1999-01-01T23:59:59.000Z

398

Iterative Methods for Neutron Transport Eigenvalue Problems  

Science Conference Proceedings (OSTI)

We discuss iterative methods for computing criticality in nuclear reactors. In general this requires the solution of a generalized eigenvalue problem for an unsymmetric integro-differential operator in six independent variables, modeling transport, scattering, ... Keywords: criticality, generalized eigenvalue problem, inexact inverse iteration, neutron transport, symmetry

Fynn Scheben; Ivan G. Graham

2011-09-01T23:59:59.000Z

399

CALIFORNIA ENERGY Small HVAC Problems and Potential  

E-Print Network (OSTI)

CALIFORNIA ENERGY COMMISSION Small HVAC Problems and Potential Savings Reports Summary of Problems of the Integrated Design of Small Commercial HVAC Systems research project. The reports are a result of funding: Productivity and Interior Environments Integrated Design of Large Commercial HVAC Systems Integrated Design

400

Dual extragradient algorithms extended to equilibrium problems  

Science Conference Proceedings (OSTI)

In this paper we propose two iterative schemes for solving equilibrium problems which are called dual extragradient algorithms. In contrast with the primal extragradient methods in Quoc et al. (Optimization 57(6):749---776, 2008) which require ... Keywords: Complexity, Dual extragradient algorithm, Equilibrium problem, Gap function, Nash-Cournot equilibria

Tran D. Quoc; Pham N. Anh; Le D. Muu

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Steiner Forest Orientation Problems Marek Cygan1  

E-Print Network (OSTI)

Steiner Forest Orientation Problems Marek Cygan1 , Guy Kortsarz2 , and Zeev Nutov3 1 Institute with orientation constra- ints. Given a directed graph D and a collection of ordered node pairs P let P[D] = {(u, v) P : D contains an uv-path}. In the Steiner Forest Orientation problem we are given an undirected

Kortsarz, Guy

402

Steiner Forest Orientation Problems Marek Cygan1  

E-Print Network (OSTI)

Steiner Forest Orientation Problems Marek Cygan1 , Guy Kortsarz2 , and Zeev Nutov3 1 IDSIA with orientation constra- ints. Given a directed graph D and a collection of ordered node pairs P let P[D] = {(u, v) P : D contains a uv-path}. In the Steiner Forest Orientation problem we are given an undirected

Kortsarz, Guy

403

The real problem with Merchant transmission  

SciTech Connect

Current regulatory policy distinguishes transmission investments that have primarily economic benefits from those that primarily enhance reliability. But no such dichotomy exists; congestion and reliability are inter-related in complex ways. Thus, solving the transmission investment problem is more complex than ''fixing'' merchant transmission; investment in the grid must be treated as a systems problem. (author)

Blumsack, Seth; Lave, Lester B.; Ilic, Marija

2008-03-15T23:59:59.000Z

404

Iterated local search in nurse rostering problem  

Science Conference Proceedings (OSTI)

This paper presents how to solve a nurse rostering problem over the real datasets of Centre hospitalier régional de Trois-Rivières hospital in Canada. Due to the complexity of this problem with plenty of hard constraints, we propose an ... Keywords: greedy, iterated local search, nurse rostering, tabu search

Sen Ngoc Vu, Minh H. Nhat Nguyen, Le Minh Duc, Chantal Baril, Viviane Gascon, Tien Ba Dinh

2013-12-01T23:59:59.000Z

405

Quantum Algorithms for Graph Problems -- A Survey  

E-Print Network (OSTI)

In this survey we give an overview about important methods to construct quantum algorithms and quantum lower bounds for graph problems. We show how to use these methods, and we give a summary about the quantum complexity of the most important graph problems. At the end of our paper, we give some interesting questions in this research area.

Sebastian Dörn

2006-01-01T23:59:59.000Z

406

The 2-hop spanning tree problem  

Science Conference Proceedings (OSTI)

A spanning tree in a graph G where each node has distance at most 2 from a root node r is called a 2-hop spanning tree. For given edge weights the 2-hop spanning tree problem is to find a minimum weight 2-hop spanning tree. The problem is NP-hard. We ... Keywords: Hop-constrained spanning tree, Integer programming, Polyhedra

Geir Dahl

1998-08-01T23:59:59.000Z

407

Fuel cycle problems in fusion reactors  

SciTech Connect

Fuel cycle problems of fusion reactors evolve around the breeding, recovery, containment, and recycling of tritium. These processes are described, and their implications and alternatives are discussed. Technically, fuel cycle problems are solvable; economically, their feasibility is not yet known. (auth)

Hickman, R.G.

1976-01-13T23:59:59.000Z

408

DNA Repair Biomarkers Predict Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer  

SciTech Connect

Purpose: The addition of neoadjuvant chemoradiotherapy prior to surgical resection for esophageal cancer has improved clinical outcomes in some trials. Pathologic complete response (pCR) following neoadjuvant therapy is associated with better clinical outcome in these patients, but only 22% to 40% of patients achieve pCR. Because both chemotherapy and radiotherapy act by inducing DNA damage, we analyzed proteins selected from multiple DNA repair pathways, using quantitative immunohistochemistry coupled with a digital pathology platform, as possible biomarkers of treatment response and clinical outcome. Methods and Materials: We identified 79 patients diagnosed with esophageal cancer between October 1994 and September 2002, with biopsy tissue available, who underwent neoadjuvant chemoradiotherapy prior to surgery at the Massachusetts General Hospital and used their archived, formalin-fixed, paraffin-embedded biopsy samples to create tissue microarrays (TMA). TMA sections were stained using antibodies against proteins in various DNA repair pathways including XPF, FANCD2, PAR, MLH1, PARP1, and phosphorylated MAPKAP kinase 2 (pMK2). Stained TMA slides were evaluated using machine-based image analysis, and scoring incorporated both the intensity and the quantity of positive tumor nuclei. Biomarker scores and clinical data were assessed for correlations with clinical outcome. Results: Higher scores for MLH1 (p = 0.018) and lower scores for FANCD2 (p = 0.037) were associated with pathologic response to neoadjuvant chemoradiation on multivariable analysis. Staining of MLH1, PARP1, XPF, and PAR was associated with recurrence-free survival, and staining of PARP1 and FANCD2 was associated with overall survival on multivariable analysis. Conclusions: DNA repair proteins analyzed by immunohistochemistry may be useful as predictive markers for response to neoadjuvant chemoradiotherapy in patients with esophageal cancer. These results are hypothesis generating and need confirmation in an independent data set.

Alexander, Brian M., E-mail: bmalexander@lroc.harvard.edu [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, Massachusetts (United States); Wang Xiaozhe [On-Q-ity, Inc., Waltham, Massachusetts (United States); Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Weaver, David T. [On-Q-ity, Inc., Waltham, Massachusetts (United States); Mak, Raymond H. [Department of Radiation Oncology, Dana-Farber/Brigham and Women's Cancer Center, Boston, Massachusetts (United States); Roof, Kevin S. [Southeast Radiation Oncology, Charlotte, North Carolina (United States); Fidias, Panagiotis [Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts (United States); Wain, John [Department of Surgery, Massachusetts General Hospital, Boston, Massachusetts (United States); Choi, Noah C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

2012-05-01T23:59:59.000Z

409

Development and validation of nondestructive inspection techniques for composite doubler repairs on commercial aircraft  

SciTech Connect

Composite doublers, or repair patches, provide an innovative repair technique which can enhance the way aircraft are maintained. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is possible to bond a single boron-epoxy composite doubler to the damaged structure. In order for the use of composite doublers to achieve widespread use in the civil aviation industry, it is imperative that methods be developed which can quickly and reliably assess the integrity of the doubler. In this study, a specific composite application was chosen on an L-1011 aircraft in order to focus the tasks on application and operation issues. Primary among inspection requirements for these doublers is the identification of disbonds, between the composite laminate and aluminum parent material, and delaminations in the composite laminate. Surveillance of cracks or corrosion in the parent aluminum material beneath the doubler is also a concern. No single nondestructive inspection (NDI) method can inspect for every flaw type, therefore it is important to be aware of available NDI techniques and to properly address their capabilities and limitations. A series of NDI tests were conducted on laboratory test structures and on full-scale aircraft fuselage sections. Specific challenges, unique to bonded composite doubler applications, were highlighted. An array of conventional and advanced NDI techniques were evaluated. Flaw detection sensitivity studies were conducted on applicable eddy current, ultrasonic, X-ray and thermography based devices. The application of these NDI techniques to composite doublers and the results from test specimens, which were loaded to provide a changing flaw profile, are presented in this report. It was found that a team of these techniques can identify flaws in composite doubler installations well before they reach critical size.

Roach, D.; Walkington, P.

1998-05-01T23:59:59.000Z

410

Suberoylanilide Hydroxyamic Acid Modification of Chromatin Architecture Affects DNA Break Formation and Repair  

Science Conference Proceedings (OSTI)

Purpose: Chromatin-modifying compounds that inhibit the activity of histone deacetylases have shown potency as radiosensitizers, but the action of these drugs at a molecular level is not clear. Here we investigated the effect of suberoylanilide hydroxyamic acid (SAHA) on DNA breaks and their repair and induction of rearrangements. Methods and Materials: The effect of SAHA on both clonogenic survival and repair was assessed using cell lines SCC-25, MCF7, and TK6. In order to study unique DNA double-strand breaks, anti-CD95 antibody was employed to introduce a DNA double-strand break at a known location within the 11q23 region. The effects of SAHA on DNA cleavage and rearrangements were analyzed by ligation-mediated PCR and inverse PCR, respectively. Results: SAHA acts as radiosensitizer at 1 {mu}M, with dose enhancement factors (DEFs) at 10% survival of: SCC-25 - 1.24 +- 0.05; MCF7 - 1.16 +- 0.09 and TK6 - 1.17 +- 0.05, and it reduced the capacity of SCC-25 cells to repair radiation induced lesions. Additionally, SAHA treatment diffused site-specific fragmentation over at least 1 kbp in TK6 cells. Chromosomal rearrangements produced in TK6 cells exposed to SAHA showed a reduction in microhomology at the breakpoint between 11q23 and partner chromosomes. Conclusions: SAHA shows efficacy as a radiosensitizer at clinically obtainable levels. In its presence, targeted DNA strand breaks occur over an expanded region, indicating increased chromatin access. The rejoining of such breaks is degraded by SAHA when measured as rearrangements at the molecular level and rejoining that contributes to cell survival.

Singh, Sheetal; Le Hongan; Shih, S.-J.; Ho, Bay [Department of Radiation Oncology, University of California at Davis, 4501 X St., Sacramento, California 95817 (United States); Vaughan, Andrew T., E-mail: andrew.vaughan@ucdmc.ucdavis.ed [Department of Radiation Oncology, University of California at Davis, 4501 X St., Sacramento, California 95817 (United States); Department of Veterans Affairs, Mather, California 95655 (United States)

2010-02-01T23:59:59.000Z

411

Physics 105. Mechanics. Professor Dine Fall, 2005. Handout: The Kepler Problem  

E-Print Network (OSTI)

+ cos() (11) Every high school student knows this is an ellipse! Of course, I am not a high school E = -µk2 2 2 , as expected. Second, let's draw the curve, for = .2484, .967. Finally, let's cast

California at Santa Cruz, University of

412

Student's algorithm solves real-world problem  

NLE Websites -- All DOE Office Websites (Extended Search)

Student's algorithm solves real-world problem Student's algorithm solves real-world problem Supercomputing Challenge: student's algorithm solves real-world problem Students learn how to use powerful computers to analyze, model, and solve real-world problems. April 3, 2012 Jordon Medlock of Albuquerque's Manzano High School won the 2012 Lab-sponsored Supercomputing Challenge Jordon Medlock of Albuquerque's Manzano High School won the 2012 Lab-sponsored Supercomputing Challenge by creating a computer algorithm that automates the process of counting and analyzing plaques, substances in the blood such as fat and cholesterol found in persons diagnosed with Alzheimer's disease. Contact Kurt Steinhaus (505) 665-7370 Email "The mission of the Supercomputing Challenge is to teach students how to use powerful computers to analyze, model, and solve real-world problems,"

413

Exactly solvable quantum Sturm-Liouville problems  

Science Conference Proceedings (OSTI)

The harmonic oscillator with time-dependent parameters covers a broad spectrum of physical problems from quantum transport, quantum optics, and quantum information to cosmology. Several methods have been developed to quantize this fundamental system, such as the path integral method, the Lewis-Riesenfeld time invariant method, the evolution operator or dynamical symmetry method, etc. In all these methods, solution of the quantum problem is given in terms of the classical one. However, only few exactly solvable problems of the last one, such as the damped oscillator or the Caldirola-Kanai model, have been treated. The goal of the present paper is to introduce a wide class of exactly solvable quantum models in terms of the Sturm-Liouville problem for classical orthogonal polynomials. This allows us to solve exactly the corresponding quantum parametric oscillators with specific damping and frequency dependence, which can be considered as quantum Sturm-Liouville problems.

Bueyuekasik, Sirin A.; Pashaev, Oktay K. [Department of Mathematics, Izmir Institute of Technology, Urla, Izmir 35430 (Turkey); Tigrak-Ulas, Esra [Astronomy, Kapteyn Institute, University of Groningen, Zernike Gebouw, Landleven, 12 9747 AD Groningen (Netherlands)

2009-07-15T23:59:59.000Z

414

Welding and Repair Technology Center: Assessment of Friction Stir Welding for Nuclear Applications  

Science Conference Proceedings (OSTI)

This report describes a study that was conducted to determine the usability of friction stir welding (FSW) for the repair of nuclear power plant components. The first phase of the study has performinged in air and underwater welding on 304 SS, 308L SS, Alloy182, and Alloy 600 test plates. In addition, crack sealing tests were carried out using electric discharge machining notches in these test plates. A patch seal test was also added to the test matrix to determine if a flat plate could be ...

2012-12-12T23:59:59.000Z

415

BWRVIP-53-A: BWR Vessel and lnternals Project, Standby Liquid Control Line Repair Design Criteria  

Science Conference Proceedings (OSTI)

The Boiling Water Reactor Vessel and Internals Project (BWRVIP), formed in June, 1994, is an association of utilities focused exclusively on BWR vessel and internals issues. This BWRVIP report documents criteria which can be used to design a repair for the standby liquid control (SLC) line in a BWR. A previous version of this report was published as BWRVIP-53 (TR-108716). This report (BWRVIP-53- A) incorporates changes proposed by the BWRVIP in response to U.S. Nuclear Regulatory Commission (NRC) Request...

2005-09-07T23:59:59.000Z

416

Counter Current Multiplier Mechanism  

NLE Websites -- All DOE Office Websites (Extended Search)

Counter Current Multiplier Mechanism Counter Current Multiplier Mechanism Name: Stephen Location: N/A Country: N/A Date: N/A Question: Can you please explain to me the counter-current multiplier mechanism. I understand that cholride and sodium ions are filtered out of the ascending loop of Henle into the interstial fluid, however, I'm not sure exactly what happens from there and how this effects osmotic pressure gradients in the nephron. Any help would be greatly appriciated. Replies: This mechanism is very complex when it comes to writing a response. You have to have a strong background in osmotic pressure understanding and the anatomy of the kidney. It involves the cortex, outer and inner medula in relationship to the vasa recta, interstitial fluids at two points, the loop of Henle and the collecting duct. The size of the tubes and the position in relations to the cortex and medulla is an essential part. I can suggest some references.

417

Mechanical Testing of Plastics  

Science Conference Proceedings (OSTI)

Table 7   ASTM and ISO mechanical test standards for plastics...by pendulum method D 1938 6383-1 Tear propagation resistance of plastic film and thin

418

Conservative-Bayesian Mechanisms  

E-Print Network (OSTI)

We put forward a new class of mechanisms. In this extended abstract, we exemplify our approach only for single-good auctions in what we call a conservative-Bayesian setting. (Essentially, no common-knowledge about the ...

Azar, Pablo

2010-09-08T23:59:59.000Z

419

Load-balancing mechanism for the RFID middleware applications over grid networking  

Science Conference Proceedings (OSTI)

RFID middleware often has to process enormous amounts of data, possibly causes overloading and leading to data errors. Therefore, RFID middleware applications require load-balancing mechanisms. This work proposes a grid-based load-balancing mechanism ... Keywords: Grid networking, Load-balancing mechanism, Middleware, Overloading problem, RFID networks

Yi-Wei Ma; Han-Chieh Chao; Jiann-Liang Chen; Cheng-Yen Wu

2011-05-01T23:59:59.000Z

420

Cosmic Rays during BBN as Origin of Lithium Problem  

E-Print Network (OSTI)

There may be non-thermal cosmic rays during big-bang nucleosynthesis (BBN) epoch (dubbed as BBNCRs). This paper investigated whether such BBNCRs can be the origin of Lithium problem or not. It can be expected that BBNCRs flux will be small in order to keep the success of standard BBN (SBBN). With favorable assumptions on the BBNCR spectrum between 0.09 -- 4 MeV, our numerical calculation showed that extra contributions from BBNCRs can account for the $^7$Li abundance successfully. However $^6$Li abundance is only lifted an order of magnitude, which is still much lower than the observed value. As the deuteron abundance is very sensitive to the spectrum choice of BBNCRs, the allowed parameter space for the spectrum is strictly constrained. We should emphasize that the acceleration mechanism for BBNCRs in the early universe is still an open question. For example, strong turbulent magnetic field is probably the solution to the problem. Whether such a mechanism can provide the required spectrum deserves further studies.

Ming-ming Kang; Yang Hu; Hong-bo Hu; Shou-hua Zhu

2011-10-02T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

REACTOR CONTROL MECHANISM  

DOE Patents (OSTI)

A quick-releasing mechanism is described which may be used to rapidiy drop a device supported from beneath during normal use, such as a safety rod in a nuclear reactor. In accordance with this invention an electrical control signal, such as may be provided by radiation detection or other alarm condition sensing devices, is delivered to an electromagnetic solenoid, the armature of which is coupled to an actuating mechanism. The solenoid is energized when the mechanism is in its upper or cocked position. In such position, the mechanism engages a plurality of retaining balls, forcing them outward into engagement with a shoulder or recess in a corresponding section of a tubular extension on the upheld device. When the control signal to the solenoid suddenly ceases, the armature drops out, allowing the actuating mechanism to move slightly but rapidly under the force of a compressed spring. The weight of the device will urge the balls inward against a beveled portion of the actuating mechanism and away from the engaging section on the tubular extension, thus allowing the upheld device to fall freely under the influence of gravity.

Lane, J.A.; Engberg, R.E.; Welch, J.M.

1959-05-12T23:59:59.000Z

422

New directions in enumerative chess problems  

E-Print Network (OSTI)

Normally a chess problem must have a unique solution, and is deemed unsound even if there are alternatives that differ only in the order in which the same moves are played. In an enumerative chess problem, the set of moves in the solution is (usually) unique but the order is not, and the task is to count the feasible permutations via an isomorphic problem in enumerative combinatorics. Almost all enumerative chess problems have been ``series-movers'', in which one side plays an uninterrupted series of moves, unanswered except possibly for one move by the opponent at the end. This can be convenient for setting up enumeration problems, but we show that other problem genres also lend themselves to composing enumerative problems. Some of the resulting enumerations cannot be shown (or have not yet been shown) in series-movers. This article is based on a presentation given at the banquet in honor of Richard Stanley's 60th birthday, and is dedicated to Stanley on this occasion.

Noam D. Elkies

2005-08-31T23:59:59.000Z

423

Houston, we have a problem...: a survey of actual problems in computer games development  

Science Conference Proceedings (OSTI)

This paper presents a survey of problems found in the development process of electronic games. These problems were collected mainly from game postmortems and specialized litterature on game development, allowing a comparison with respect to well-known ... Keywords: electronic games, game development, postmortems, problems in game development, survey

Fábio Petrillo; Marcelo Pimenta; Francisco Trindade; Carlos Dietrich

2008-03-01T23:59:59.000Z

424

SIENA Customer Problem Statement and Requirements  

Science Conference Proceedings (OSTI)

This document describes the problem domain and functional requirements of the SIENA framework. The software requirements and system architecture of SIENA are specified in separate documents (called SIENA Software Requirement Specification and SIENA Software Architecture, respectively). While currently this version of the document describes the problems and captures the requirements within the Analysis domain (concentrating on finite element models), it is our intention to subsequent y expand this document to describe problems and capture requirements from the Design and Manufacturing domains. In addition, SIENA is designed to be extendible to support and integrate elements from the other domains (see SIENA Software Architecture document).

L. Sauer; R. Clay; C. Adams; H. Walther; B. Allan; R. Mariano; C. Poore; B. Whiteside; B. Boughton; J. Dike; E. Hoffman; R. Hogan; C. LeGall

2000-08-01T23:59:59.000Z

425

Inverse hyperbolic problems and optical black holes  

E-Print Network (OSTI)

In this paper we give a more geometrical formulation of the main theorem in [E1] on the inverse problem for the second order hyperbolic equation of general form with coefficients independent of the time variable. We apply this theorem to the inverse problem for the equation of the propagation of light in a moving medium (the Gordon equation). Then we study the existence of black and white holes for the general hyperbolic and for the Gordon equation and we discuss the impact of this phenomenon on the inverse problems.

Gregory Eskin

2008-09-23T23:59:59.000Z

426

Mitigating PQ Problems in Legacy Data Centers  

Science Conference Proceedings (OSTI)

The conclusions of this presentation are: (1) Problems with PQ in legacy data centers still exist and need to be mitigated; (2) Harmonics generated by non-linear IT load can be lowered by passive, active and hybrid cancellation methods; (3) Harmonic study is necessary to find the best way to treat PQ problems; (4) AHF's and harmonic cancellation transformers proved to be very efficient in mitigating PQ problems; and (5) It is important that IT leaders partner with electrical engineering to appropriate ROI statements, justifying many of these expenditures.

Ilinets, Boris; /SLAC

2011-06-01T23:59:59.000Z

427

TopBP1 associates with NBS1 and is involved in homologous recombination repair  

SciTech Connect

TopBP1 is involved in DNA replication and DNA damage checkpoint. Recent studies have demonstrated that TopBP1 is a direct positive effecter of ATR. However, it is not known how TopBP1 recognizes damaged DNA. Here, we show that TopBP1 formed nuclear foci after exposure to ionizing radiation, but such TopBP1 foci were abolished in Nijmegen breakage syndrome cells. We also show that TopBP1 physically associated with NBS1 in vivo. These results suggested that NBS1 might regulate TopBP1 recruitment to the sites of DNA damage. TopBP1-depleted cells showed hypersensitivity to Mitomycin C and ionizing radiation, an increased frequency of sister-chromatid exchange level, and a reduced frequency of DNA double-strand break induced homologous recombination repair. Together, these results suggested that TopBP1 might be a mediator of DNA damage signaling from NBS1 to ATR and promote homologous recombination repair.

Morishima, Ken-ichi [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Sakamoto, Shuichi; Kobayashi, Junya [Department of Genome Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan); Izumi, Hideki; Suda, Tetsuji; Matsumoto, Yoshiyuki [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Tauchi, Hiroshi [Department of Environmental Sciences, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Ide, Hiroshi [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8562 (Japan); Komatsu, Kenshi [Department of Genome Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan); Matsuura, Shinya [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan)], E-mail: shinya@hiroshima-u.ac.jp

2007-11-03T23:59:59.000Z

428

Applying Case-Based Reasoning to Mechanical Bearing Design  

E-Print Network (OSTI)

Case-Based Reasoning (CBR) provides a promising methodology for solving many complex engineering design problems. CBR is based on the idea that past problem-solving experiences can be reused and learned from in solving new problems. This paper presents an overview of a CBR design system to assist human engineers in performing mechanical bearing design. It retrieves previously designed cases from a case-base and uses adaptation techniques to adapt them to satisfy the current problem requirements. Our approach combines parametric adaptations and constraint satisfaction adaptations. The technique of parametric adaptation considers not only parameter substitution, but also the interrelationships between the problem definition and its solution. The technique of constraint satisfaction adaptation provides a method to globally check the design requirements to assess case adaptability. Currently, our system has been tested in the rolling bearing domain.

Xiaoli Qin; William C. Regli

2000-01-01T23:59:59.000Z

429

Jar mechanism energizer  

Science Conference Proceedings (OSTI)

An energizer for use with a jar mechanism incorporated on inner and outer bodies in a well string to assist the jar mechanism in delivering an upward jar to the well string includes longitudinally spaced seal means between the inner and outer bodies forming a chamber for receiving a compressible medium therein. A differential area formed on one of the bodies within the compressible medium chamber compresses a compressible medium in the chamber as the well string is lowered to position the inner and outer bodies so that the jar mechanism is actuated to restrain relative longitudinal movement between the inner and outer bodies to an extended position whereby a pull force may be developed in the well string in one of the bodies. The differential area is responsive to the compressed gas in the chamber to assist the jar mechanism in applying an upward jarring force when the jar mechanism, in response to a predetermined pull force in the well string, releases the bodies for contact to apply an upward force to the well string.

Webb, D. D.; Anderson, E. A.

1985-10-08T23:59:59.000Z

430

Jar mechanism accelerator  

SciTech Connect

This patent describes an accelerator for use with a jar mechanism in a well pipe string to enhance the jarring impact delivered to a stuck object wherein the jar mechanism includes inner and outer members for connection, respectively, between the well pipe string the stuck object. The jar mechanism members are constructed to (1) restrict relative longitudinal movement therebetween to build up energy in the well pipe string and accelerator and then (2) to release the jar mechanism members for unrestrained, free relative longitudinal movement therebetween to engage jarring surfaces on the jar mechanism members for delivering a jarring impact to the stuck object. The accelerator includes: inner and outer telescopically connected members relatively movable longitudinally to accumulate energy in the accelerator; the inner and outer accelerator members each having means for connecting the accelerator in the well pipe string; means associated with the inner and outer members for initially accomodating a predetermined minimum length of unrestrained, free relative longitudinal movement between the inner and outer accelerator members.

Anderson, E.A.; Webb, D.D.

1989-07-11T23:59:59.000Z

431

Repair and Strengthening by Use of Superficial Fixed Laminates of Cracked Masonry Walls Sheared Horizontally-Laboratory Tests  

Science Conference Proceedings (OSTI)

There are many methods of crack repairing in masonry structures. One of them is repair and strengthening by using of superficial fixed laminates, especially in case of masonry walls with plastering on their both sides. The initial laboratory tests of three different types of strengthening of diagonal cracked masonry wallettes are presented. Tests concerned three clay brick masonry walls subjected to horizontal shearing with two levels of precompression and strengthened by flexible polymer injection, superficial glass fixed by polymer fibre laminate plates and using of CRFP strips stiff fixed to the wall surface by polymer and stiff resin epoxy fixing are presented and discussed.

Kubica, Jan [Department of Structural Engineering, Silesian University of Technology, Akademicka 5, PL-44-100 Gliwice (Poland); Kwiecien, Arkadiusz; Zajac, Boguslaw [Department of Civil Engineering, Cracow University of Technology, Warszawska 24, PL-31-155 Krakow (Poland)

2008-07-08T23:59:59.000Z

432

Planning and care mark repair of 14-year old leak in Kuwait Oil Co. LPG tank 95  

SciTech Connect

This paper points out that the leak, which had been present for such a long time, completely saturated the perlite insulation with hydrocarbons, thus rendering the entire operation of inspection, repair, and maintenance of the inner tank a hazardous operation. It emphasizes the safety aspects, which were complicated by the saturated perlite as well as by the fact that the tank is situated in the middle of the LPG storage area with LPG tanks on either side. Tank design, making preparations, inspection, and repair are discussed. The fact that the leaking flanges were originally installed damaged, indicated the future need of tighter company quality control of all contractors work.

Shtayieh, S.

1983-01-10T23:59:59.000Z

433

The Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays,  

NLE Websites -- All DOE Office Websites (Extended Search)

Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, PET, and Gamma-rays Douglas Boreham McMaster University Abstract The goal of this project was to investigate low dose ionizing radiation effects associated with exposure to diagnostic computed tomography (CT) or positron emission tomography (PET) scans. Biological effects were evaluated in wild type and Trp53+/- heterozygous females, following in vivo exposure to diagnostic CT (75kVp, 200µ) or PET (18F-FDG) scans. The short term biological effects following CT or PET scans were evaluated in order to understand biological modification of mechanisms, such as DNA repair processes and apoptosis, that might alter long term cancer risk. Corresponding life-time cancer risk studies are in progress. Short-term

434

Modeling the Black Hole Excision Problem  

E-Print Network (OSTI)

We analyze the excision strategy for simulating black holes. The problem is modeled by the propagation of quasi-linear waves in a 1-dimensional spatial region with timelike outer boundary, spacelike inner boundary and a horizon in between. Proofs of well-posed evolution and boundary algorithms for a second differential order treatment of the system are given for the separate pieces underlying the finite difference problem. These are implemented in a numerical code which gives accurate long term simulations of the quasi-linear excision problem. Excitation of long wavelength exponential modes, which are latent in the problem, are suppressed using conservation laws for the discretized system. The techniques are designed to apply directly to recent codes for the Einstein equations based upon the harmonic formulation.

B. Szilagyi; H-O. Kreiss; J. Winicour

2004-12-21T23:59:59.000Z

435

Parallel Displacement Decomposition Solvers for Elasticity Problems  

Science Conference Proceedings (OSTI)

This article describes the displacement decomposition and its benefits for the parallelization of the preconditioned conjugate gradient method for finite element elasticity problems. It deals with both the fixed and variable preconditioning based on ...

Radim Blaheta; Ondrej Jakl; Jiri Stary

2001-09-01T23:59:59.000Z

436

An effective algorithm of motif finding problem  

Science Conference Proceedings (OSTI)

Identification of the short DNA sequence motif, which serves as binding targets for transcription factors, is a fundamental problem in both computer science and molecular biology. Especially, finding the subtle motifs with variable gaps is more challenging. ...

Yong Chen; Guojun Li

2008-05-01T23:59:59.000Z

437

A multiple secretary problem with switch costs  

E-Print Network (OSTI)

In this thesis, we utilize probabilistic reasoning and simulation methods to determine the optimal selection rule for the secretary problem with switch costs, in which a known number of applicants appear sequentially in a ...

Ding, Jiachuan

2007-01-01T23:59:59.000Z

438

ADAM: a problem-oriented symbol processor  

Science Conference Proceedings (OSTI)

Digital computers have evolved in their own technical environment, and to a large degree independently of the problem environment. Thus it was necessary to have computing centers with staffs of programmers as intermediaries between machines and users. ...

A. P. Mullery; R. F. Schauer; R. Rice

1963-05-01T23:59:59.000Z

439

The Logical Problem of Language Change  

E-Print Network (OSTI)

This paper considers the problem of language change. Linguists must explain not only how languages are learned but also how and why they have evolved along certain trajectories and not others. While the language ...

Niyogi, Partha

1995-12-01T23:59:59.000Z

440

Maximum Empirical Likelihood: Empty Set Problem  

E-Print Network (OSTI)

resulted in the extension of ESP into aESP A feedback fromand therefore may be subject to the empty set problem (ESP).In other words, ESP introduces the possibility that for the

Grendar, Marian; Judge, George G

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Online decision problems with large strategy sets  

E-Print Network (OSTI)

In an online decision problem, an algorithm performs a sequence of trials, each of which involves selecting one element from a fixed set of alternatives (the "strategy set") whose costs vary over time. After T trials, the ...

Kleinberg, Robert David

2005-01-01T23:59:59.000Z

442

Numerical solution methods for differential game problems  

E-Print Network (OSTI)

Differential game theory provides a potential means for the parametric analysis of combat engagement scenarios. To determine its viability for this type of analysis, three frameworks for solving differential game problems ...

Johnson, Philip A. (Philip Arthur)

2009-01-01T23:59:59.000Z

443

The Group Diffie-Hellman Problems  

Science Conference Proceedings (OSTI)

In this paper we study generalizations of the Diffie-Hellman problems recently used to construct cryptographic schemes for practical purposes. The Group Computational and the Group Decisional Diffie-Hellman assumptions not only enable one to construct ...

Emmanuel Bresson; Olivier Chevassut; David Pointcheval

2002-08-01T23:59:59.000Z

444

Detached shock problem and related topics  

Science Conference Proceedings (OSTI)

A finite difference method for solving the Cauchy or initial value problem for elliptic partial differential equations as introduced in (1) and further developed in (2) will be the principal topic discussed here. Involved in this discussion, also, will ...

H. M. Lieberstein

1959-09-01T23:59:59.000Z

445

Nogood Recording for Valued Constraint Satisfaction Problems  

Science Conference Proceedings (OSTI)

In the frame of classical Constraint Satisfaction Problems (CSPs), the backtrack tree search, combined with learning methods, presents a double advantage: for static solving, it improves the search speed by avoiding redundant explorations; for dynamic ...

P. Dago; G. Verfailllie

1996-11-01T23:59:59.000Z

446

Solution to the Dark Energy Problem  

E-Print Network (OSTI)

I present a simple, and hopefully convincing, discussion of a solution to the dark energy problem, which arises because the visible universe is well approximated by a black hole.

Frampton, Paul Howard

2010-01-01T23:59:59.000Z

447

Essays on the principal-expert problem  

E-Print Network (OSTI)

This dissertation studies the problem of motivating an expert to help a principal take a decision. The first chapter examines a principal-expert model in which the only source of friction is that the expert must be induced ...

Zermeño Vallés, Luis G. (Luis Guillermo)

2012-01-01T23:59:59.000Z

448

test problem for packing_sumit  

E-Print Network (OSTI)

Test problems of circles in circle packing with constraints and known the optimal solutions*. Hong-fei Teng1, 2**, Chao Che 2, Yu Chen 1, Yi-shou Wang 1. 1.

449

Exact Algorithms for Combinatorial Optimization Problems with ...  

E-Print Network (OSTI)

Fuchs [10] showed that the problem of finding a minimum-power connected network with ... receiving node, in the latter all nodes except the source are addressed. ..... As an alternative, one could use an algorithm for general submodular ...

450

Nonlinear boundary value problem of magnetic insulation  

E-Print Network (OSTI)

On the basis of generalization of upper and lower solution method to the singular two point boundary value problems, the existence theorem of solutions for the system, which models a process of magnetic insulation in plasma is proved.

A. V. Sinitsyn

2000-09-09T23:59:59.000Z

451

Universal Forces and the Dark Energy Problem  

E-Print Network (OSTI)

The Dark Energy problem is forcing us to re-examine our models and our understanding of relativity and space-time. Here a novel idea of Fundamental Forces is introduced. This allows us to perceive the General Theory of Relativity and Einstein's Equation from a new pesrpective. In addition to providing us with an improved understanding of space and time, it will be shown how it leads to a resolution of the Dark Energy problem.

Afsar Abbas

2007-04-01T23:59:59.000Z

452

Universal Forces and the Dark Energy Problem  

E-Print Network (OSTI)

The Dark Energy problem is forcing us to re-examine our models and our understanding of relativity and space-time. Here a novel idea of Fundamental Forces is introduced. This allows us to perceive the General Theory of Relativity and Einstein's Equation from a new pesrpective. In addition to providing us with an improved understanding of space and time, it will be shown how it leads to a resolution of the Dark Energy problem.

Abbas, Afsar

2007-01-01T23:59:59.000Z

453

Experimental unsaturated soil mechanics  

E-Print Network (OSTI)

In this general report, experimental systems and procedures of investigating the hydro-mechanical behaviour of unsaturated soils are presented. The water retention properties of unsaturated soils are commented and linked to various physical parameters and properties of the soils. Techniques of controlling suction are described together with their adaptation in various laboratory testing devices. Some typical features of the mechanical behaviour of unsaturated soils are presented within an elasto-plastic framework. An attempt to describe the numerous and significant recent advances in the investigation of the behaviour of unsaturated soils, including the contributions to this Conference, is proposed.

Delage, Pierre

2008-01-01T23:59:59.000Z

454

Geological problems in radioactive waste isolation  

SciTech Connect

The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately.

Witherspoon, P.A. (ed.)

1991-01-01T23:59:59.000Z

455

Geological problems in radioactive waste isolation  

SciTech Connect

The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately.

Witherspoon, P.A. (ed.)

1991-01-01T23:59:59.000Z

456

Subj: Educational and General (E&G) Facility Support Provide an overview of Facility Operations, Maintenance, Repair and Renovation and Space  

E-Print Network (OSTI)

and infrastructure. Facilities Energy & Utilities: Energy and Utilities is responsible for campus-wide utility and maintain this system and its components. Deferred Maintenance: Given the age of buildings and the wear buildings and infrastructure in working order. Minor and Major Repairs: Generally, minor repairs include

Pohl, Karsten

457

Co-evolutionary particle swarm optimization to solve constrained optimization problems  

Science Conference Proceedings (OSTI)

This paper presents a co-evolutionary particle swarm optimization (CPSO) algorithm to solve global nonlinear optimization problems. A new co-evolutionary PSO (CPSO) is constructed. In the algorithm, a deterministic selection strategy is proposed to ensure ... Keywords: Co-evolutionary, Diversity mechanism, Extrapolation, Global nonlinear optimization, Infeasible degree, Particle swarm optimization

Xiaoli Kou; Sanyang Liu; Jianke Zhang; Wei Zheng

2009-06-01T23:59:59.000Z

458

Accelerated staggered coupling schemes for problems of thermoelasticity at finite strains  

Science Conference Proceedings (OSTI)

This paper introduces a fully implicit partitioned coupling scheme for problems of thermoelasticity at finite strains utilizing the p-version of the finite element method. The mechanical and the thermal fields are partitioned into symmetric subproblems ... Keywords: Convergence acceleration, Partitioned coupling schemes, Thermoelasticity, Time adaptivity

Patrick Erbts; Alexander DüSter

2012-10-01T23:59:59.000Z

459

What Do Aging, Exercise, Swallowing Problems, and Nerve Growth Factors Have in Common?  

E-Print Network (OSTI)

What Do Aging, Exercise, Swallowing Problems, and Nerve Growth Factors Have in Common? Allison J. Schaser, M.S., Kyle Stang, Nadine P. Connor, PhD & Mary Behan, PhD Methods 48 rats in 3 age groups were ages. We studied one possible mechanism that might be responsible for improvement: a change in levels

Sheridan, Jennifer

460

DEPARTMENT OF MECHANICAL ENGINEERING  

E-Print Network (OSTI)

the Chair Advanced Power Systems Research Group Engineering Education Innovation Research Group Mechanics of MultiScale Materials Research Group MultiScale Systems and Sensors Research Group Space Systems Research Group Sustainable Manufacturing and Design Research Group Faculty Profiles Michigan

Endres. William J.

Note: This page contains sample records for the topic "mechanical problems repairs" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

MECHANICAL TEST LAB CAPABILITIES  

E-Print Network (OSTI)

MECHANICAL TEST LAB CAPABILITIES · Static and cyclic testing (ASTM and non-standard) · Impact drop testing · Slow-cycle fatigue testing · High temperature testing to 2500°F · ASTM/ Boeing/ SACMA standard testing · Ability to design and fabricate non-standard test fixtures and perform non-standard tests

462

SAFETY-MECHANICAL STANDARDS  

SciTech Connect

Hanford Atomic Production Operation specification guides and standards for plumbing, chemical ngineering, mechanical engineering, sanitary engineering, exhaust systems, steam engineering, stainless steel, dry boxes, thermal insulation, filtration, and materials testing are presented. Details of this manual are given in TID-4100 (Suppl.). (N.W.R.)

1964-10-31T23:59:59.000Z

463

Higgs Mechanism for Gravitons  

E-Print Network (OSTI)

Just like the vector gauge bosons in the gauge theories, it is now known that gravitons acquire mass in the process of spontaneous symmetry breaking of diffeomorphisms through the condensation of scalar fields. The point is that we should find the gravitational Higgs mechanism such that it results in massive gravity in a flat Minkowski space-time without non-unitary propagating modes. This is usually achieved by including higher-derivative terms in scalars and tuning the cosmological constant to be a negative value in a proper way. Recently, a similar but different gravitational Higgs mechanism has been advocated by Chamseddine and Mukhanov where one can relax the negative cosmological constant to zero or positive one. In this work, we investigate why the non-unitary ghost mode decouples from physical Hilbert space in a general space-time dimension. Moreover, we generalize the model to possess an arbitrary potential and clarify under what conditions the general model exhibits the gravitational Higgs mechanism. By searching for solutions to the conditions, we arrive at two classes of potentials exhibiting gravitational Higgs mechanism. One class includes the model by Chamseddine and Mukhanov in a specific case while the other is completely a new model.

Ichiro Oda

2010-03-07T23:59:59.000Z

464

Fractals and quantum mechanics  

Science Conference Proceedings (OSTI)

A new application of a fractal concept to quantum physics has been developed. The fractional path integrals over the paths of the Lévy flights are defined. It is shown that if fractality of the Brownian trajectories leads to standard quantum mechanics

Nick Laskin

2000-01-01T23:59:59.000Z

465

Quantum Mechanics and Black Holes  

E-Print Network (OSTI)

This paper discusses the existence of black holes from the foundations of quantum mechanics. It is found that quantum mechanics rule out a possible gravitational collapse.

Jose N. Pecina-Cruz

2005-11-11T23:59:59.000Z

466

Evaluating the Yield of Repairable SRAMs for Marco Ottavi, Member, IEEE, Luca Schiano, Student Member, IEEE, Xiaopeng Wang Member, IEEE,  

E-Print Network (OSTI)

the different processes for preserving the quality of the shipped product. An accurate estimate of the yield (i issues revolving around cost-effective BIST and ATE-based solutions for higher test transparency Equipment (ATE) application. The first method is based on the sum of probabilities of all repairable fault

Ayers, Joseph

467

A mechanical model for Fourier's law of heat conduction  

E-Print Network (OSTI)

Nonequilibrium statistical mechanics close to equilibrium is a physically satisfactory theory centered on the linear response formula of Green-Kubo. This formula results from a formal first order perturbation calculation without rigorous justification. A rigorous derivation of Fourier's law for heat conduction from the laws of mechanics remains thus a major unsolved problem. In this note we present a deterministic mechanical model of a heat-conducting chain with nontrivial interactions, where kinetic energy fluctuations at the nodes of the chain are removed. In this model the derivation of Fourier's law can proceed rigorously.

David Ruelle

2011-02-27T23:59:59.000Z

468

Urban agriculture as a tool for neighborhood fabric repair in post-industrial Detroit.  

E-Print Network (OSTI)

??This thesis focuses on Detroit as a post-industrial city that suffers from abandonment, vacancy, and food security issues. I address this problem through the lens… (more)

Fairbank, Sandra Trubow

2011-01-01T23:59:59.000Z

469

Microsoft Word - CX-IndianCabinRoadRepair_PPA1908_WEB.doc  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

United States Government Department of Energy United States Government Department of Energy Bonneville Power Administration DATE: June 22, 2011 REPLY TO ATTN OF: KEP-4 SUBJECT: Environmental Clearance Memorandum Elizabeth Johnson Natural Resource Specialist - TFBV-THE DALLES Proposed Action: Indian Cabin Road Repair PP&A Project No.: 1908 Categorical Exclusions Applied (from Subpart D, 10 C.F.R. Part 1021): B1.3, Routine maintenance activities...for structures, rights of way, infrastructures such as roads, equipment... routine maintenance activities, corrective....are required to maintain...infrastructures...in a condition suitable for a facility to be used for its designated purpose. Location: The project is located in Skamania County, Washington, T3N, R8E, Sections 27

470

Repair, sidetrack, drilling, and completion of EE-2A for Phase 2 reservoir production service  

DOE Green Energy (OSTI)

Hot Dry Rock (HDR) geothermal energy well EE-2 at Fenton Hill, New Mexico, was sidetracked and redrilled into the HDR Phase II reservoir after two unsuccessful attempts to repair damage in the lower wellbore. Before sidetracking was begun, six cement slurries were pumped to plug the abandoned lower wellbore and to support the production casing where drilling wear was predicted and where sidetracking was to occur. This work and the redrill of EE-2A were completed in November 1987. Specifications were prepared for a state-of-the-art tie-back casing, which was procured, manufactured, and delivered to Fenton Hill in May 1988. The well was then completed in June 1988 for hot-water production service by cementing in a liner and the upper section of production casing and installing and cementing a tie-back casing string. 24 refs., 17 figs., 5 tabs.

Dreesen, D.S.; Cocks, G.G.; Nicholson, R.W.; Thomson, J.C.

1989-08-01T23:59:59.000Z

471

MOLECULAR MECHANISM OF SUPPRESSION OF NEOPLASTIC TRANSFORMATION BY LOW DOSES OF LOW LET RADIATION  

Science Conference Proceedings (OSTI)

We are currently funded (9/01-8/04) by the DOE Low Dose Radiation Research Program to examine mechanisms underlying the suppression of neoplastic transformation in vitro by low doses of low LET radiation. For the new studies proposed under Notice 04-21, we intend to follow up on our observation that upregulation of DNA repair may be an important factor and that its importance is dose-dependent. The experimental system will be the human hybrid cell neoplastic transformation assay that we are currently using. We propose to test the following hypothesis: Down-regulation of DNA dsb repair will abrogate the low dose suppression of neoplastic transformation. Using the technique of RNA silencing, it is proposed to test the effect of down-regulation of the two major DNA dsb repair pathways, homologous recombination (HR) and non-homologous end-joining (NHEJ), on the dose response relationship for neoplastic transformation. Based on prior studies, we predict that this will result in abrogation of the suppressive effect at doses in the range 1 to 10 cGy, but not at lower doses. The proposed experiments will also help address the question as to which of the two DNA repair pathways may be the most important in causing suppression of transformation. HR is a pathway that is predominant in S and G2 phase cells and is known to be less error-prone than the NHEJ pathway that is predominant in G1 phase. We hypothesize that down-regulation of HR will result in the most effective abrogation of suppression. An important component of this study will be the determination of the how abrogation of DNA dsb repair impacts the spontaneous transformation frequency, presumably a consequence of endogeneous DNA damage. Experiments will be carried out using partially synchronized populations of cells enriched for G1 and S/G2 respectively. In addition to the endpoint of neoplastic transformation the impact of down-regulation of HR and NHEJ on the formation and disappearance of the DNA dsb marker, gamma-H2AX, will be studied.

J.LESIE REDPATH, PH.D.

2011-03-29T23:59:59.000Z

472

Frequency Instability Problems in North American Interconnections  

NLE Websites -- All DOE Office Websites (Extended Search)

Frequency Instability Problems in Frequency Instability Problems in North American Interconnections May 1, 2011 DOE/NETL-2011/1473 Frequency Instability Problems in North American Interconnections Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

473

Sierra/solid mechanics 4.22 user's guide.  

Science Conference Proceedings (OSTI)

Sierra/SolidMechanics (Sierra/SM) is a Lagrangian, three-dimensional code for the analysis of solids and structures. It provides capabilities for explicit dynamic and implicit quasistatic and dynamic analyses. The explicit dynamics capabilities allow for the efficient and robust solution of models subjected to large, suddenly applied loads. For implicit problems, Sierra/SM uses a multi-level iterative solver, which enables it to effectively solve problems with large deformations, nonlinear material behavior, and contact. Sierra/SM has a versatile library of continuum and structural elements, and an extensive library of material models. The code is written for parallel computing environments, and it allows for scalable solutions of very large problems for both implicit and explicit analyses. It is built on the SIERRA Framework, which allows for coupling with other SIERRA mechanics codes. This document describes the functionality and input structure for Sierra/SM.

Thomas, Jesse David

2011-10-01T23:59:59.000Z

474

Hybrid preconditioning for iterative diagonalization of ill-conditioned generalized eigenvalue problems in electronic structure calculations  

E-Print Network (OSTI)

The iterative diagonalization of a sequence of large ill-conditioned generalized eigenvalue problems is a computational bottleneck in quantum mechanical methods employing a nonorthogonal basis for {\\em ab initio} electronic structure calculations. We propose a hybrid preconditioning scheme to effectively combine global and locally accelerated preconditioners for rapid iterative diagonalization of such eigenvalue problems. In partition-of-unity finite-element (PUFE) pseudopotential density-functional calculations, employing a nonorthogonal basis, we show that the hybrid preconditioned block steepest descent method is a cost-effective eigensolver, outperforming current state-of-the-art global preconditioning schemes, and comparably efficient for the ill-conditioned generalized eigenvalue problems produced by PUFE as the locally optimal block preconditioned conjugate-gradient method for the well-conditioned standard eigenvalue problems produced by planewave methods.

Cai, Yunfeng; Pask, John E; Sukumar, N

2013-01-01T23:59:59.000Z

475

Mechanical Operations and Maintenance  

NLE Websites -- All DOE Office Websites (Extended Search)

Holiday Work Status Holiday Work Status Mechanical Operations & Maintenance Group APS Storage Ring Magnets The Advanced Photon Source (APS) at the Argonne National Laboratory is a national synchrotron-radiation research facility funded by the U.S. Department of Energy. Using high-brilliance x-ray beams from the APS, an international community of scientists conducts forefront basic and applied research in the fields of material science, biological science, physics, chemistry, environmental, geophysical and planetary science. The 1.1-km circumference APS facility consists of several major subsystems including magnets, vacuum chambers, radio-frequency cavities, diagnostics instrumentation, x-ray absorbers and apertures, and cooling water subsystems. Each of these subsystems contains hundreds of mechanical

476

NUT SCREW MECHANISMS  

DOE Patents (OSTI)

A reactor control mechanism is described wherein the control is achieved by the partial or total withdrawal of the fissile material which is in the form of a fuel rod. The fuel rod is designed to be raised and lowered from the reactor core area by means of two concentric ball nut and screw assemblies that may telescope one within the other. These screw mechanisms are connected through a magnetic clutch to a speed reduction gear and an accurately controllable prime motive source. With the clutch energized, the fuel rod may be moved into the reactor core area, and fine adjustments may be made through the reduction gearing. However, in the event of a power failure or an emergency signal, the magnetic clutch will become deenergized, and the fuel rod will drop out of the core area by the force of gravity, thus shutting down the operation of the reactor.

Glass, J.A.F.

1958-07-01T23:59:59.000Z

477

Inverse Problems in Classical and Quantum Physics  

E-Print Network (OSTI)

The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. In this thesis, also two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A promising result is that one can qualitatively reconstruct the conductivity inside the cross-section of a human chest. Even though the human volunteer is neither two-dimensional nor circular, such reconstructions can be useful in medical applications: monitoring for lung problems such as accumulating fluid or a collapsed lung and noninvasive monitoring of heart function and blood flow.

Andrea A. Almasy

2009-12-02T23:59:59.000Z

478

Testing quantum mechanics  

E-Print Network (OSTI)

As experiments continue to push the quantum-classical boundary to include increasingly complex dynamical systems, the interpretation of experimental data becomes more and more challenging: when the observations are noisy, indirect, and limited, how can we be sure that we are observing quantum behavior? This tutorial highlights some of the difficulties in such experimental tests of quantum mechanics, using optomechanics as the central example, and discusses how the issues can be resolved using techniques from statistics and insights from quantum information theory.

Mankei Tsang

2013-06-12T23:59:59.000Z

479

Mechanical Compression Heat Pumps  

E-Print Network (OSTI)

Mechanical compression heat pumping is not new in industrial applications. In fact, industry history suggests that the theoretical concept was developed before 1825. Heat pump manufacturers gained the support of consultants and end-users when the energy crisis hit this country in 1973. That interest, today, has been dampened because there is a current abundance of the basic sources of industrial energy (namely oil and natural gas). Meanwhile, Mycom used the window of the current opportunities to develop, design and test compressors built to meet the needs of the mechanically demanding industrial heat pump applications which often require high compression ratios and temperatures in excess of 200 degrees F. This paper will review the theoretical foundation for heat pumps and present the mechanical and thermal requirements of the compressors which constitute the heart and soul of the system. It will also provide a quick survey of the available types of compressors for heat pumping and some of the industrial processes where simultaneous heating and cooling proceed along parallel demand paths. The case history will examine the system flexibility and the economic advantages realized in a barley malting process.

Apaloo, T. L.; Kawamura, K.; Matsuda, J.

1986-06-01T23:59:59.000Z

480

Multi-Period Combinatorial Auction Mechanism for Distributed Resource Allocation and Scheduling  

Science Conference Proceedings (OSTI)

We consider the problem of resource allocation and scheduling where information and decisions are decentralized, and our goal is to propose a market mechanism that allows resources from a central resource pool to be allocated to distributed decision ...

Hoong Chuin Lau; Shih Fen Cheng; Thin Yin Leong; Jong Han Park; Zhengyi Zhao

2007-11-01T23:59:59.000Z

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481

Transport Test Problems for Hybrid Methods Development  

Science Conference Proceedings (OSTI)

This report presents 9 test problems to guide testing and development of hybrid calculations for the ADVANTG code at ORNL. These test cases can be used for comparing different types of radiation transport calculations, as well as for guiding the development of variance reduction methods. Cases are drawn primarily from existing or previous calculations with a preference for cases which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22.

Shaver, Mark W.; Miller, Erin A.; Wittman, Richard S.; McDonald, Benjamin S.

2011-12-28T23:59:59.000Z

482

Planning lessens problems, gets benefits of underbalance  

Science Conference Proceedings (OSTI)

A horizontal well planned to be drilled underbalanced required special procedures and countermeasures to prevent formation damage from the mud and downhole tool failures from high temperature. Drilling the well underbalanced helped reduce problems from lost returns and from solids entering and plugging the natural fractures in the Austin chalk. The high bottom hole temperature in the deep Austin chalk in central Louisiana complicates drilling, the mud program, and well design. The first of this two-part series covers the planning, procedures, and well design to alleviate these problems. The next article, which will appear in a future issue, addresses complications during the operation and the equipment used.

Joseph, R.A. [OXY U.S.A. Inc., Houston, TX (United States)

1995-03-20T23:59:59.000Z

483

Problems continue to plague electronic ballast industry  

SciTech Connect

Problems of unreliable components, poor quality due to the lack of performance testing standards, and electromagnetic radiation are preventing the electronic ballast industry from achieving the anticipated 40% electricity savings and have led several manufacturers to drop out of the market. The National Association of Lighting Maintenance Contractors (NALMCO) recognized the problem, and the remaining manufacturers plan to reduce the number of components to improve reliability until standards are developed. Many potential users are waiting for a larger selection and better product before they invest in electronic ballasts. A directory of major lighting equipment manufacturers accompanies the article. (DCK)

Warrock, A.M.

1983-10-17T23:59:59.000Z

484

Measurement of Mechanical and Electrical  

Science Conference Proceedings (OSTI)

Measurement of Mechanical and Electrical Properties of Ultra-thin Insulating Films. NIST Nanomechanical Properties Group ...

2012-10-01T23:59:59.000Z

485

Fundamental Interaction Mechanisms of Engineered ...  

Science Conference Proceedings (OSTI)

Fundamental Interaction Mechanisms of Engineered Nanomaterials with DNA. Summary: We utilized isotope-dilution liquid ...

2012-10-01T23:59:59.000Z

486

Understanding Bohmian mechanics: A dialogue  

E-Print Network (OSTI)

This paper is an introduction to the ideas of Bohmian mechanics, an interpretation of quantum mechanics in which the observer plays no fundamental role. Bohmian mechanics describes, instead of probabilities of measurement results, objective microscopic events. In recent years, Bohmian mechanics has attracted increasing attention by researchers. The form of a dialogue allows me to address questions about the Bohmian view that often arise.

Roderich Tumulka

2004-08-18T23:59:59.000Z

487

Bohmian Mechanics Detlef Durr1  

E-Print Network (OSTI)

Bohmian Mechanics Detlef D¨urr1 , Sheldon Goldstein2 , Roderich Tumulka3 , and Nino Zangh`i4, Via Dodecaneso 33, 16146 Genova, Italy. E-mail: zanghi@ge.infn.it #12;Bohmian mechanics is a theory mechanics, observers see the same statistics for experimental results as predicted by quantum mechanics

Goldstein, Sheldon

488

CIVIL INFRASTRUCTURE ADVANCED SENSING TECHNOLOGIES AND ADVANCED REPAIR MATERIALS FOR THE INFRASTRUCTURE: WATER SYSTEMS, DAMS, LEVEES, BRIDGES, ROADS, AND HIGHWAYS  

E-Print Network (OSTI)

Technology (NIST) was established for the purpose of assisting U.S. businesses and institutions of higher education or other organizations, such as national laboratories and nonprofit research institutions, to support, promote, and accelerate innovation in the United States through highrisk, high-reward research in areas of Critical National Need (CNN). Areas of Critical National Need are those areas that justify government attention because the magnitude of the problem is large and societal challenges that can be overcome with technology are not being sufficiently addressed. TIP seeks to support accelerating high-risk, transformative research targeted to address key societal challenges. Funding selections will be merit-based, and may be provided to industry (small and medium-sized businesses), universities, and consortia. The primary mechanism for this support is cost-shared cooperative agreements awarded on the basis of merit competitions.

unknown authors

2009-01-01T23:59:59.000Z

489

The quantization of unimodular gravity and the cosmological constant problem  

E-Print Network (OSTI)

A quantization of unimodular gravity is described, which results in a quantum effective action which is also unimodular, ie a function of a metric with fixed determinant. A consequence is that contributions to the energy momentum tensor of the form of the metric times a spacetime constant, whether classical or quantum, are not sources of curvature in the equations of motion derived from the quantum effective action. This solves the first cosmological constant problem, which is suppressing the enormous contributions to the cosmological constant coming from quantum corrections. We discuss several forms of uniodular gravity and put two of them, including one proposed by Henneaux and Teitelboim, in constrained Hamiltonian form. The path integral is constructed from the latter. Furthermore, the second cosmological constant problem, which is why the measured value is so small, is also addressed by this theory. We argue that a mechanism first proposed by Ng and van Dam for suppressing the cosmological constant by quantum effects obtains at the semiclassical level.

Lee Smolin

2009-04-30T23:59:59.000Z

490

Mechanisms Underlying Cellular Responses to Low Dose/Low LET...  

NLE Websites -- All DOE Office Websites (Extended Search)

expression, chromosomal and apoptotic analysis suggest a model for strain specific radiation response; normal DNA damage recognition and repair leading to cell death and...

491

On the geomagnetic directional problem: A uniqueness result  

E-Print Network (OSTI)

On the geomagnetic directional problem: A uniqueness result Ralf Kaiser Fakultat fur Mathematik = f D. This problem is related to the problem of reconstructing the geomagnetic #12;eld outside on S. Key words: Nonlinear boundary value problem, geomagnetism, directional problem 35J65, 86A25 1

Kaiser, Ralf

492

Differential nested lattice encoding for consensus problems  

Science Conference Proceedings (OSTI)

In this paper we consider the problem of transmitting quantized data while performing an average consensus algorithm. Average consensus algorithms are protocols to compute the average value of all sensor measurements via near neighbors communications. ... Keywords: average consensus, coding with side information, consensus, nested lattice coding, predictive coding

Mehmet E. Yildiz; Anna Scaglione

2007-04-01T23:59:59.000Z

493

MIRPLib: A Maritime Inventory Routing Problem Library  

E-Print Network (OSTI)

additional vessels can also be chartered on the spot market. A path-flow ...... On the other hand, if regional information is not specified in the problem, one can create an .... For a more detailed analysis of the tradeoff between speed ...... In Energy, Natural Resources and Environmental Economics, pages 427–439. Springer ...

494

Comonotonic approximations for optimal portfolio selection problems  

E-Print Network (OSTI)

We investigate multiperiod portfolio selection problems in a Black & Scholes type market where a basket of 1 riskfree and m risky securities are traded continuously. We look for the optimal allocation of wealth within the class of ’constant mix ’ portfolios. First, we consider the portfolio selection problem of a decision maker who invests money at predetermined points in time in order to obtain a target capital at the end of the time period under consideration. A second problem concerns a decision maker who invests some amount of money (the initial wealth or provision) in order to be able to fullfil a series of future consumptions or payment obligations. Several optimality criteria and their interpretation within Yaari’s dual theory of choice under risk are presented. For both selection problems, we propose accurate approximations based on the concept of comonotonicity, as studied in Dhaene, Denuit, Goovaerts, Kaas & Vyncke (2002 a,b). Our analytical approach avoids simulation, and hence reduces the computing effort drastically. 1

J. Dhaene; S. Vanduffel; M. J. Goovaerts; R. Kaas; D. Vyncke

2005-01-01T23:59:59.000Z

495

Applying Adaptive Evolutionary Algorithms to Hard Problems  

E-Print Network (OSTI)

Applying Adaptive Evolutionary Algorithms to Hard Problems J.I. van Hemert1 jvhemert into two distinct parts. The main theme is adaptive evolutionary algorithms. The rst part covers. The second part mainly consists of the development of a library. Its use is aimed at evolutionary algorithms

Emmerich, Michael

496

Optimum LDPC decoder: a memory architecture problem  

Science Conference Proceedings (OSTI)

This paper addresses a frequently overlooked problem: designing a memory architecture for an LDPC decoder. We analyze the requirements to support the codes defined in the IEEE 802.11n and 802.16e standards. We show a design methodology for a flexible ... Keywords: LDPC codes, low power architectures, memory optimization

Erick Amador; Renaud Pacalet; Vincent Rezard

2009-07-01T23:59:59.000Z

497

Department of Mathematics Analysis Inverse Problems  

E-Print Network (OSTI)

McLaughlin In this talk we report the application of level-set techniques for reservoir facies for data inversion in reservoir modeling, Inverse Problems, 25 (2009), 035006. [4] M. A. Iglesias and D. McLaughlin.40­14.05 Anastasia Cornelio (Modena, Italy) Regularized Nonlinear Least Squares Methods for Hit Position

Hofmann, Bernd

498

Solving Water Quality Problems in the Home  

E-Print Network (OSTI)

If your drinking water comes from a private water well, there are certain procedures you can follow to make sure the water is safe. This publication explains how to get your water tested and, if treatment is necessary, to select the correct treatment equipment. Tables display common water problems and the equipment used to treat them.

Dozier, Monty; McFarland, Mark L.

2004-02-20T23:59:59.000Z

499

Cyclic coordinate descent in hydrothermal nonsmooth problems  

Science Conference Proceedings (OSTI)

In this paper we present an algorithm, inspired by the cyclic coordinate descent method, which allows the solution of hydrothermal optimization problems involving pumped-storage plants. The proof of the convergence of the succession generated by the ... Keywords: Coordinate descent, Hydrothermal coordination, Optimal control, Zangwill's theorem

Luis Bayón; Jose M. Grau; Maria M. Ruiz; Pedro M. Suárez

2012-02-01T23:59:59.000Z

500

An introduction to the dark energy problem  

E-Print Network (OSTI)

In this work we review briefly the origin and history of the cosmological constant and its recent reincarnation in the form of the dark energy component of the universe. We also comment on the fundamental problems associated to its existence and magnitude which require and urgent solution for the sake of the internal consistency of theoretical physics.

Antonio Dobado; Antonio L. Maroto

2008-02-13T23:59:59.000Z