National Library of Energy BETA

Sample records for brittle material failure

  1. Brittle failure kinetics model for concrete

    SciTech Connect (OSTI)

    Silling, S.A.

    1997-03-01

    A new constitutive model is proposed for the modeling of penetration and large stress waves in concrete. Rate effects are incorporated explicitly into the damage evolution law, hence the term brittle failure kinetics. The damage variable parameterizes a family of Mohr-Coulomb strength curves. The model, which has been implemented in the CTH code, has been shown to reproduce some distinctive phenomena that occur in penetration of concrete targets. Among these are the sharp spike in deceleration of a rigid penetrator immediately after impact. Another is the size scale effect, which leads to a nonlinear scaling of penetration depth with penetrator size. This paper discusses the theory of the model and some results of an extensive validation effort.

  2. Fabrication of brittle materials -- current status

    SciTech Connect (OSTI)

    Scattergood, R.O.

    1988-12-01

    The research initiatives in the area of precision fabrication will be continued in the upcoming year. Three students, T. Bifano (PhD), P. Blake (PhD) and E. Smith (MS), finished their research programs in the last year. Sections 13 and 14 will summarize the essential results from the work of the Materials Engineering students Blake and Smith. Further details will be presented in forthcoming publications that are now in preparation. The results from Bifano`s thesis have been published in adequate detail and need not be summarized further. Three new students, S. Blackley (MS), H. Paul (PhD), and S. Smith (PhD) have joined the program and will continue the research efforts in precision fabrication. The programs for these students will be outlined in Sections 15 and 16. Because of the success of the earlier work in establishing new process models and experimental techniques for the study of diamond turning and diamond grinding, the new programs will, in part, build upon the earlier work. This is especially true for investigations concerned with brittle materials. The basic understanding of material response of nominally brittle materials during machining or grinding operations remains as a challenge. The precision fabrication of brittle materials will continue as an area of emphasis for the Precision Engineering Center.

  3. Fracture mechanics applied to the machining of brittle materials

    SciTech Connect (OSTI)

    Hiatt, G.D.; Strenkowski, J.S.

    1988-12-01

    Research has begun on incorporating fracture mechanics into a model of the orthogonal cutting of brittle materials. Residual stresses are calculated for the machined material by a combination of Eulerian and Lagrangian finite element models and then used in the calculation of stress intensity factors by the Green`s Function Method.

  4. Microfracturing, damage, and failure of brittle granites and Ze'ev Reches

    E-Print Network [OSTI]

    Ze'ev, Reches

    Microfracturing, damage, and failure of brittle granites Oded Katz1 and Ze'ev Reches Institute; accepted 17 October 2003; published 20 January 2004. [1] The evolution of stress-induced damage the damage intensity in two methods and directly compare model predictions and actual damage. The 14 samples

  5. Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle material

    E-Print Network [OSTI]

    Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle are derived either at microscale with random distribution of material properties or at a mesoscale

  6. Simulations of ductile flow in brittle material processing

    SciTech Connect (OSTI)

    Luh, M.H.; Strenkowski, J.S.

    1988-12-01

    Research is continuing on the effects of thermal properties of the cutting tool and workpiece on the overall temperature distribution. Using an Eulerian finite element model, diamond and steel tools cutting aluminum have been simulated at various, speeds, and depths of cut. The relative magnitude of the thermal conductivity of the tool and the workpiece is believed to be a primary factor in the resulting temperature distribution in the workpiece. This effect is demonstrated in the change of maximum surface temperatures for diamond on aluminum vs. steel on aluminum. As a preliminary step toward the study of ductile flow in brittle materials, the relative thermal conductivities of diamond on polycarbonate is simulated. In this case, the maximum temperature shifts from the rake face of the tool to the surface of the machined workpiece, thus promoting ductile flow in the workpiece surface.

  7. The effect of complex inclusion geometries on fracture and crack coalescence behavior in brittle material

    E-Print Network [OSTI]

    Morgan, Stephen Philip

    2011-01-01

    This research study investigates the cracking processes in a brittle material associated with inclusions of varying shape, orientation and materials. Specifically, this study summarizes a series of uniaxial compression ...

  8. Fatigue cracking in materials with brittle surface coatings

    SciTech Connect (OSTI)

    Suresh, S.; Sugimura, Y.; Ogawa, T. (Brown Univ., Providence, RI (United States))

    1993-07-15

    Ceramic coatings enhance the resistance of metal alloys to wear, oxidation, thermal exposure, corrosion, erosion and delamination in a variety of structural, optical, electrical , electronic and bioengineering applications. Recent experimental work on steel-steel bimaterials has shown that the conditions for the growth or arrest of a fatigue crack, which approaches the interface between the two steels perpendicularly, are determined by whether the crack propagates to the interface from the weaker or the stronger material. Specifically, it is found that as the fatigue crack advances toward the interface from the weaker steel, the interaction of the crack-tip plastic zone with the interface results in the arrest of the crack. However, when the fatigue crack is propagated from the stronger to the weaker steel, crack growth occurs unimpeded through the interface. In this paper, the authors present additional experimental and mechanistic descriptions of fatigue crack growth normal to interfaces. They then apply the mechanisms underlying these experiments to the design of fatigue-resistant surface coatings for alloys. In particular, they demonstrate experimentally that a fatigue crack emanating from the brittle outercoating and advancing into the substrate can be arrested and/or deflected by proper choices of ductile interlayers. Experimental results of fatigue crack profiles and high-cycle fatigue lives are presented for two different coated materials: a steel coated with a Cr[sub 2]O[sub 3] layer and a steel coated with a Cr[sub 2]O[sub 3] outerlayer and a soft Ni-Al interlayer. The paper also includes a brief discussion of the application of proposed concepts to nitrided titanium alloys.

  9. Fracture process zone : microstructure and nanomechanics in quasi-brittle materials

    E-Print Network [OSTI]

    Brooks, Zenzile (Zenzile Z.)

    2013-01-01

    Cracks begin (and end) at a crack tip; the "Fracture Process Zone" (FPZ) is a region of damage around the crack tip. The context of this research is the FPZ in quasi-brittle materials, which is characterized by cracking ...

  10. ON THE INDENTATION AND EROSION OF BRITTLE MATERIALS

    E-Print Network [OSTI]

    Khatibloo, M.A.

    2013-01-01

    fracture toughness. Critical Angle of Attack as a Function of Material Deformation The difference between ductile and

  11. Scale effects for strength, ductility, and toughness in "brittle" materials W.W. Gerbericha)

    E-Print Network [OSTI]

    Ballarini, Roberto

    Scale effects for strength, ductility, and toughness in "brittle" materials W.W. Gerbericha parameters. This gives proportionality between fracture toughness and the other mechanical properties, there has been a flourish of activity to measure length scale effects in the strength, ductility, toughness

  12. Material brittle fracture owing to thermoelastic effect of high energy nuclear particle

    SciTech Connect (OSTI)

    Kalinichenko, A.I.

    1996-12-31

    Rapid arising of the overheated domain near very heavy ion path (near fast neutron collision point) in solid results in generation of cylinder (spherical) thermoelastic stress wave. The latter can exceed the material strength and cause brittle fracture at going out on the free body interface. Size and shape of an erosion zone as well as erosion rate for both sorts of primary nuclear particles are found. The role of wave attenuation is discussed. The products of erosion are of macroscopic scaly particles having the typical thickness (1 {divided_by} 5) {center_dot} 10{sup -7} cm and mass 10{sup -18} {divided_by} 10{sup -17} g. Such ion (neutron)-stimulated thermoacoustic grinding can take place in radioactive materials with fissionable addenda. The consideration of the brittle destruction under cosmic ray bombardment may be essential for equipment of deep space missions.

  13. Large-Scale Atomistic Simulations of Material Failure

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Abraham, Farid [IBM Almaden Research; Duchaineau, Mark [LLNL; Wirth, Brian [LLNL; Heidelberg,; Seager, Mark [LLNL; De La Rubia, Diaz [LLNL

    These simulations from 2000 examine the supersonic propagation of cracks and the formation of complex junction structures in metals. Eight simulations concerning brittle fracture, ductile failure, and shockless compression are available.

  14. 1MSE 2090: Introduction to Materials Science Chapter 8, Failure How do Materials Break?

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    Outline: Failure Ductile vs. brittle fracture Principles of fracture mechanics Stress concentration Impact Alloys for high-temperature use Not tested: in 8.5 Fracture Toughness 8.14 Data extrapolation methods #12 two fracture modes can be defined - ductile or brittle · Ductile fracture - most metals (not too cold

  15. A micromechanical basis for partitioning the evolution of grainbridging in brittle materials

    SciTech Connect (OSTI)

    Foulk III, J.W.; Cannon, R.M.; Johnson, G.C.; Klein, P.A.; Ritchie, R.O.

    2006-10-09

    A micromechanical model is developed for grain bridging inmonolithic ceramics. Specifically, bridge formation of a single,non-equiaxed grain spanning adjacent grains is addressed. A cohesive zoneframework enables crack initiation and propagation along grainboundaries. The evolution of the bridge is investigated through avariance in both grain angle and aspect ratio. We propose that thebridging process can be partitioned into five distinct regimes ofresistance: propagate, kink, arrest, stall, and bridge. Although crackpropagation and kinking are well understood, crack arrest and subsequent"stall" have been largely overlooked. Resistance during the stall regimeexposes large volumes of microstructure to stresses well in excess of thegrain boundary strength. Bridging can occur through continued propagationor reinitiation ahead of the stalled crack tip. The driving forcerequired to reinitiate is substantially greater than the driving forcerequired to kink. In addition, the critical driving force to reinitiateis sensitive to grain aspect ratio but relatively insensitive to grainangle. The marked increase in crack resistance occurs prior to bridgeformation and provides an interpretation for the rapidly risingresistance curves which govern the strength of many brittle materials atrealistically small flaw sizes.

  16. Strengthening, Crack Arrest And Multiple Cracking In Brittle Materials Using Residual Stresses.

    DOE Patents [OSTI]

    Green, David J. (State College, PA); Sglavo, Vincenzo M. (Roncegno, IT); Tandon, Rajan (Fremont, CA)

    2003-02-11

    Embodiments include a method for forming a glass which displays visible cracking prior to failure when subjected to predetermined stress level that is greater than a predetermined minimum stress level and less than a failure stress level. The method includes determining a critical flaw size in the glass and introducing a residual stress profile to the glass so that a plurality of visible cracks are formed prior to failure when the glass is subjected to a stress that is greater than the minimum stress level and lower than the critical stress. One method for forming the residual stress profile includes performing a first ion exchange so that a first plurality of ions of a first element in the glass are exchanged with a second plurality of ions of a second element that have a larger volume than the first ions. A second ion exchange is also performed so that a plurality of the second ions in the glass are exchanged back to ions of the first element.

  17. FAILURE PREDICTION AND STRESS ANALYSIS OF MICROCUTTING TOOLS 

    E-Print Network [OSTI]

    Chittipolu, Sujeev

    2010-07-14

    -based products are limited because silicon is brittle. Products can be made from other engineering materials and need to be machined in microscale. This research deals with predicting microtool failure by studying spindle runout and tool deflection effects...

  18. Brittle Fracture Ductile to Brittle transition

    E-Print Network [OSTI]

    Subramaniam, Anandh

    FRACTURE Brittle Fracture Ductile to Brittle transition Fracture Mechanics T.L. Anderson CRC sulphur in steel Residual stress Continuity of the structure Microcracks #12;Fracture Brittle Ductile Factors affecting fracture Strain rate State of stress Temperature #12;Behaviour described Terms Used

  19. Failure Stress and Apparent Elastic Modulus of Diesel Particulate Filter Ceramics

    Broader source: Energy.gov [DOE]

    Three established mechanical test specimen geometries and test methods for brittle materials are adapted to DPF architecture to evaluate failure initiation stress and apparent elastic modulus of the ceramics.

  20. Fracture Mechanics and Failure Analysis

    E-Print Network [OSTI]

    New South Wales, University of

    concepts: Griffith criterion, K=Ya, K=KIC, ductile and brittle fracture, cyclic fatigue, environmentally, yield criteria. 4 Elastic-Plastic Analysis 5 Fracture toughness testing 6 Crack Growth Resistance - RMATS4004 Fracture Mechanics and Failure Analysis Course Outline Session 1, 2015 School of Materials

  1. Damage mechanisms in the dynamic fracture of nominally brittle polymers

    E-Print Network [OSTI]

    Davy Dalmas; Claudia Guerra; Julien Scheibert; Daniel Bonamy

    2013-04-23

    Linear Elastic Fracture Mechanics (LEFM) provides a consistent framework to evaluate quantitatively the energy flux released to the tip of a growing crack. Still, the way in which the crack selects its velocity in response to this energy flux remains far from completely understood. To uncover the underlying mechanisms, we experimentally studied damage and dissipation processes that develop during the dynamic failure of polymethylmethacrylate (PMMA), classically considered as the archetype of brittle amorphous materials. We evidenced a well-defined critical velocity along which failure switches from nominally-brittle to quasi-brittle, where crack propagation goes hand in hand with the nucleation and growth of microcracks. Via post-mortem analysis of the fracture surfaces, we were able to reconstruct the complete spatiotemporal microcracking dynamics with micrometer/nanosecond resolution. We demonstrated that the true local propagation speed of individual crack fronts is limited to a fairly low value, which can be much smaller than the apparent speed measured at the continuum-level scale. By coalescing with the main front, microcracks boost the macroscale velocity through an acceleration factor of geometrical origin. We discuss the key role of damage-related internal variables in the selection of macroscale fracture dynamics.

  2. Effect of Load Path on Mode of Failure at the Brittle-ductile Transition in Well-sorted Aggregates of St. Peter Sand 

    E-Print Network [OSTI]

    Dilci, Gokturk Mehmet

    2010-10-12

    Granular aggregates of quartz subjected to triaxial compression under constant effective pressures (Pe) undergo macroscopic failure at critical stress states that depend on the effective mean stress. Although the mode ...

  3. Molecular dynamics studies of brittle fracture in vitreous silica: Review and recent progress

    E-Print Network [OSTI]

    Deymier, Pierre

    Molecular dynamics studies of brittle fracture in vitreous silica: Review and recent progress, Gainesville, FL 32611, USA Abstract The dynamics of brittle fracture in vitreous silica has been a subject surrounding the voids. Ó 2005 Elsevier B.V. All rights reserved. 1. Introduction Fracture in brittle materials

  4. Failure of materials. (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journal Article) |production at a linear(Conference)membranes by(Conference) |Failure

  5. Failure by fracture and fatigue in 'NANO' and 'BIO'materials

    SciTech Connect (OSTI)

    Ritchie, R.O.; Muhlstein, C.L.; Nalla, R.K.

    2003-12-19

    The behavior of nanostructured materials/small-volumestructures and biologi-cal/bio-implantable materials, so-called "nano"and "bio" materials, is currently much in vogue in materials science. Oneaspect of this field, which to date has received only limited attention,is their fracture and fatigue properties. In this paper, we examine twotopics in this area, namely the premature fatigue failure ofsilicon-based micron-scale structures for microelectromechanical systems(MEMS), and the fracture properties of mineralized tissue, specificallyhuman bone.

  6. From an adhesive to a brittle delamination model in thermo-visco-elasticity

    E-Print Network [OSTI]

    Rossi, Riccarda

    From an adhesive to a brittle delamination model in thermo-visco-elasticity Riccarda Rossi Marita words and phrases: Rate-independent evolution of adhesive contact, brittle delamination, Kelvin- Voigt of generalized standard materials [HN75]. More precisely, the adhesiveness of the bonding is modeled with the aid

  7. In-Vessel Coil Material Failure Rate Estimates for ITER Design Use

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2013-01-01

    The ITER international project design teams are working to produce an engineering design for construction of this large tokamak fusion experiment. One of the design issues is ensuring proper control of the fusion plasma. In-vessel magnet coils may be needed for plasma control, especially the control of edge localized modes (ELMs) and plasma vertical stabilization (VS). These coils will be lifetime components that reside inside the ITER vacuum vessel behind the blanket modules. As such, their reliability is an important design issue since access will be time consuming if any type of repair were necessary. The following chapters give the research results and estimates of failure rates for the coil conductor and jacket materials to be used for the in-vessel coils. Copper and CuCrZr conductors, and stainless steel and Inconel jackets are examined.

  8. Failure modes in fiber-reinforced plastic materials. Final report, September 1994

    SciTech Connect (OSTI)

    Weiss, W.; Thomas, C.; Wessels, J.

    1994-09-19

    This report describes the results of a literature review and discussions with industry experts through telephone interviews and attendance at the Natural Gas Vehicle (NGV) Exhibition and the NGV Institute's Second Annual Education Symposium. This quick-response study was precipitated by the fuel tank ruptures which occurred in early 1994 (January 18 and February 1) on two GMC Sierra dedicated natural gas pickup trucks. These vehicles were equipped with Comdyne fully-overwrapped, aluminum-lined, composite fuel cylinders. They were converted to operate on compressed natural gas. The Gas Research Institute (GRI) requested Radian Corporation to conduct the study to address their concerns about NGV composite cylinders. Specifically, GRI was interested in identifying and evaluating available information on field failures in structures of fiberglass materials systems to assist in evaluating the implications of the two NGV fuel tank ruptures.

  9. FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation

    E-Print Network [OSTI]

    Sethna, James P.

    FRACTURE IN DISORDERED BRITTLE MEDIA A Dissertation Presented to the Faculty of the Graduate School by Ashivni Shekhawat May 2013 #12;c 2013 Ashivni Shekhawat ALL RIGHTS RESERVED #12;FRACTURE IN DISORDERED- lem of brittle fracture in disordered media. Chapters 2 and 4 are concerned with various aspects

  10. DUCTILE-BRITTLE TRANSITIONS IN THE FRACTURE OF PLASTICALLY-DEFORMING, ADHESIVELY-BONDED STRUCTURES

    E-Print Network [OSTI]

    Thouless, Michael

    1 DUCTILE-BRITTLE TRANSITIONS IN THE FRACTURE OF PLASTICALLY-DEFORMING, ADHESIVELY. Historically, fracture mechanics using a single failure parameter of toughness has gained acceptance-bonded joints in steel sheets failing by mode-I fracture and plastic deformation were examined. Three types

  11. Ductile-to-brittle transition in spallation of metallic glasses

    SciTech Connect (OSTI)

    Huang, X. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang, Sichuan 621999 (China); Ling, Z. [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Dai, L. H., E-mail: lhdai@lnm.imech.ac.cn [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 10081 (China)

    2014-10-14

    In this paper, the spallation behavior of a binary metallic glass Cu{sub 50}Zr{sub 50} is investigated with molecular dynamics simulations. With increasing the impact velocity, micro-voids induced by tensile pulses become smaller and more concentrated. The phenomenon suggests a ductile-to-brittle transition during the spallation process. Further investigation indicates that the transition is controlled by the interaction between void nucleation and growth, which can be regarded as a competition between tension transformation zones (TTZs) and shear transformation zones (STZs) at atomic scale. As impact velocities become higher, the stress amplitude and temperature rise in the spall region increase and micro-structures of the material become more unstable. Therefore, TTZs are prone to activation in metallic glasses, leading to a brittle behavior during the spallation process.

  12. Modeling of Brittle to Ductile Transition in BCC metals : : Strain Rate and Temperature dependence in [alpha]-Iron and Tantalum Monocrystals

    E-Print Network [OSTI]

    Karandikar, Keyur Kashinath

    2013-01-01

    fracture toughness of the material is taken as Brittle to Ductileductile transition Materials Science and Engineering A319–321 (2001) 484–489 Kwai.S.Chan, Relationships of Fracture ToughnessFracture toughness K critical as function of temperature, Comparison of predeformed specimens to reference undeformed Tungsten monocrystal specimens[[36] Brittle Ductile

  13. On the fracture toughness of advanced materials

    E-Print Network [OSTI]

    Launey, Maximilien E.

    2009-01-01

    brittle materials, such as zirconia-based ceramics, thatpartially-stabilized zirconia, [9,10] the 2 to 4% dilation

  14. Injectable Materials for the Treatment of Myocardial Infarction and Heart Failure: The Promise of Decellularized Matrices

    E-Print Network [OSTI]

    Singelyn, Jennifer M.; Christman, Karen L.

    2010-01-01

    milieu that cannot currently be mimicked by other materials, and thus offer promising solutions as injectable therapies

  15. Brittle and ductile fracture of semiconductor nanowires --molecular dynamics simulations

    E-Print Network [OSTI]

    Cai, Wei

    Brittle and ductile fracture of semiconductor nanowires -- molecular dynamics simulations Keonwook November 9, 2006 Abstract Fracture of silicon and germanium nanowires in tension at room temperature potentials predict brittle fracture initiated by crack nucleation from the surface, most potentials predict

  16. Modeling the deformation and failure behavior of FCC and HCP nanocrystalline materials

    E-Print Network [OSTI]

    Wei, Yujie, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    As foreseen by Richard Feynman in his famous talk titled There's Plenty of Room at the Bottom in 1959, scientists nowadays are miniaturizing structures in materials to achieve better performance as concerned in technical ...

  17. THRESHOLD-BASED QUASI-STATIC BRITTLE DAMAGE ADRIANA GARRONI AND CHRISTOPHER J. LARSEN

    E-Print Network [OSTI]

    Garroni, Adriana

    THRESHOLD-BASED QUASI-STATIC BRITTLE DAMAGE EVOLUTION ADRIANA GARRONI AND CHRISTOPHER J. LARSEN Abstract We introduce models for static and quasi-static damage in elastic materials, based on a strain definition, are also global minimizers. 1. Introduction Many phenomena in mechanics, such as fracture

  18. Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight- and Shale-Gas Reservoirs: Material Failure and Enhanced Permeability

    SciTech Connect (OSTI)

    Kim, Jihoon; Moridis, George

    2014-12-01

    We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gas causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design production scenarios.

  19. Excess Vibrational Density of States and the Brittle to Ductile Transition in Crystalline and Amorphous Solids

    E-Print Network [OSTI]

    Jeetu S. Babu; Chandana Mondal; Surajit Sengupta; Smarajit Karmakar

    2015-09-01

    The conditions which determine whether a material behaves in a brittle or ductile fashion on mechanical loading are still elusive and comprise a topic of active research among materials physicists and engineers. In this study, we present results of {\\em in silico} mechanical deformation experiments from two very different model solids in two and three dimensions. The first consists of particles interacting with isotropic potentials and the other has strongly direction dependent interactions. We show that in both cases, the excess vibrational density of states is the fundamental quantity which characterises the ductility of the material. Our results can be checked using careful experiments on colloidal solids.

  20. 1 INTRODUCTION Stressing brittle rocks leads to the development of

    E-Print Network [OSTI]

    Ze'ev, Reches

    -dependent dam- age in the tested brittle granite. The stress distribu- tion results are analyzed following Lawn Mechanics Institute, University of Okla- homa, Norman, Oklahoma, and the experimental de- tails appear

  1. Structural reliability of brittle materials - an analytical method 

    E-Print Network [OSTI]

    Shields, Charles Burch

    1967-01-01

    ?:;. '. ;-' s f c)l Pier t her Zncnl i ry L:Lst of Re' E' slices ~ 3Q ~ 32 APPDIIDXG "'-' 1. An '?amole. Problem 2. Derivation of (1-Pv)=(1-Po) for the !leaI?est I &n'. c IIodel 39 3 Derivatio i of "Ic" I actors ~ g2 4. I'ao?cmuni Lil?elihood Par . metez... r. , stimators. 5. G o!::put or Pro ~ rains . 6. Co:"uu" r Pro. ?. cram List in?s. 53 ~ ~ ~ ~ Q7 LIST OF 1"1GU'i'. ". , S F!. gu e Page 1 Besult. of Testing of 113 S:&liconi, . ed BT C'029 Graphite Te. , t Speci!msns. . . . . . . . . . . 8 2...

  2. Modeling Different Failure Mechanisms in Metals 

    E-Print Network [OSTI]

    Zhang, Liang

    2012-02-14

    Material failure plays an important role in human life. By investigating the failure mechanisms, people can more precisely predict the failure conditions to develop new products, to enhance product performances, and most ...

  3. Fracture characterization of clays and clay-like materials using flattened Brazilian Test

    E-Print Network [OSTI]

    Agaiby, Shehab Sherif Wissa

    2013-01-01

    Fracture mechanics has been used for many years to study the mechanical behavior of brittle and quasi-brittle materials like concrete, rock, wood, and ceramics. To date, the application of fracture mechanics to soils has ...

  4. Failing softly: A fracture theory of highly-deformable materials

    E-Print Network [OSTI]

    Tamar Goldman Boué; Roi Harpaz; Jay Fineberg; Eran Bouchbinder

    2015-03-24

    Highly-deformable materials, from synthetic hydrogels to biological tissues, are becoming increasingly important from both fundamental and practical perspectives. Their mechanical behaviors, in particular the dynamics of crack propagation during failure, are not yet fully understood. Here we propose a theoretical framework for the dynamic fracture of highly-deformable materials, in which the effects of a dynamic crack are treated with respect to the nonlinearly deformed (pre-stressed/strained), non-cracked, state of the material. Within this framework, we derive analytic and semi-analytic solutions for the near-tip deformation fields and energy release rates of dynamic cracks propagating in incompressible neo-Hookean solids under biaxial and uniaxial loading. We show that moderately large pre-stressing has a marked effect on the stress fields surrounding a crack's tip. We verify these predictions by performing extensive experiments on the fracture of soft brittle elastomers over a range of loading levels and propagation velocities, showing that the newly developed framework offers significantly better approximations to the measurements than standard approaches at moderately large levels of external loadings and high propagation velocities. This framework should be relevant to the failure analysis of soft and tough, yet brittle, materials.

  5. Fracture Toughness of Metallic Glasses: Ductile-to-Brittle Transition?

    E-Print Network [OSTI]

    Rycroft, Chris H

    2012-01-01

    Quantitative understanding of the fracture toughness of metallic glasses, including the associated ductile-to-brittle transitions, is not yet available. Here we use a simple model of plastic deformation in glasses, coupled to an advanced Eulerian level set formulation for solving complex free boundary problems, to calculate the fracture toughness of metallic glasses as a function of the degree of structural relaxation corresponding to different annealing times near the glass temperature. Our main result indicates the existence of an elasto-plastic crack tip instability for sufficiently relaxed glasses, resulting in a marked drop in the toughness, which we interpret as a ductile-to-brittle transition similar to experimental observations.

  6. Failure of Functionally Graded Materials G.H. PAULINO,Z.-H. JIN, and R.H. DODDS,Jr.

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    .13.5.1 Metal/Ceramic FGM Fracture Specimen 638 2.13.5.2 Precracking of Metal/Ceramic FGMs 639 2 of reinforcement and matrix (base) materials in a continuous manner as illustrated by Figure 1. This new concept by providing a compositional distribution function, C(x), consistent with these condi- tions. For instance

  7. DUCTILE-BRITTLE TRANSITIONS IN THE FRACTURE OF PLASTICALLY-DEFORMING, ADHESIVELY-BONDED STRUCTURES

    E-Print Network [OSTI]

    Thouless, Michael

    1 DUCTILE-BRITTLE TRANSITIONS IN THE FRACTURE OF PLASTICALLY-DEFORMING, ADHESIVELY a catastrophic transition to a brittle mode of fracture. The cohesive parameters for both the toughened, but the toughness dropped by a factor of four upon a transition to the brittle mode. The results of wedge tests were

  8. LABORATORY TESTING OF STRESS-INDUCED BRITTLE FRACTURE DAMAGE THROUGH INCREMENTAL LOADING

    E-Print Network [OSTI]

    Eberhardt, Erik

    LABORATORY TESTING OF STRESS-INDUCED BRITTLE FRACTURE DAMAGE THROUGH INCREMENTAL LOADING Erik-induced brittle fracture damage as a function of the applied load. Strain gauge and acoustic emission measurements of brittle fracture development and to quantify the corresponding permanent strain damage. This paper reports

  9. Molecular dynamics simulations of atomic-level brittle fracture mechanisms in amorphous silica

    E-Print Network [OSTI]

    Deymier, Pierre

    Molecular dynamics simulations of atomic-level brittle fracture mechanisms in amorphous silica Abstract We have examined the atomic dynamics of the brittle fracture process in amorphous silica using the change in local coordina- tion of atoms. Introduction The brittle fracture process has been a subject

  10. Brittle Failure Design Criteria for Ductile Cast Iron Spent-Fuel

    Office of Scientific and Technical Information (OSTI)

    Am. SOC. of Mech. Engineers, (1980). 3. "Pressure Vessel Codes: Their Application to Nuclear Reactor Systems," Technical Reports Series No. 56, International Atomic Energy...

  11. Brittle Failure Design Criteria for Ductile Cast Iron Spent-Fuel

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby a contractor ofvarDOEBattery LifetimeBiomass

  12. Air-Cooled Stack Freeze Tolerance Freeze Failure Modes and Freeze Tolerance Strategies for GenDriveTM Material Handling Application Systems and Stacks Final Scientific Report

    SciTech Connect (OSTI)

    Hancock, David, W.

    2012-02-14

    Air-cooled stack technology offers the potential for a simpler system architecture (versus liquid-cooled) for applications below 4 kilowatts. The combined cooling and cathode air allows for a reduction in part count and hence a lower cost solution. However, efficient heat rejection challenges escalate as power and ambient temperature increase. For applications in ambient temperatures below freezing, the air-cooled approach has additional challenges associated with not overcooling the fuel cell stack. The focus of this project was freeze tolerance while maintaining all other stack and system requirements. Through this project, Plug Power advanced the state of the art in technology for air-cooled PEM fuel cell stacks and related GenDrive material handling application fuel cell systems. This was accomplished through a collaborative work plan to improve freeze tolerance and mitigate freeze-thaw effect failure modes within innovative material handling equipment fuel cell systems designed for use in freezer forklift applications. Freeze tolerance remains an area where additional research and understanding can help fuel cells to become commercially viable. This project evaluated both stack level and system level solutions to improve fuel cell stack freeze tolerance. At this time, the most cost effective solutions are at the system level. The freeze mitigation strategies developed over the course of this project could be used to drive fuel cell commercialization. The fuel cell system studied in this project was Plug Power's commercially available GenDrive platform providing battery replacement for equipment in the material handling industry. The fuel cell stacks were Ballard's commercially available FCvelocity 9SSL (9SSL) liquid-cooled PEM fuel cell stack and FCvelocity 1020ACS (Mk1020) air-cooled PEM fuel cell stack.

  13. Postseismic relaxation driven by brittle creep: A possible mechanism to reconcile geodetic measurements and the decay

    E-Print Network [OSTI]

    Avouac, Jean-Philippe

    associated with crystal plasticity. Hereinafter we refer to this midcrustal fault portion as the brittle Properties of Rocks: Plasticity, diffusion, and creep; 8123 Tectonophysics: Dynamics, seismotectonics; 8159

  14. Heart Failure Cardiovascular Features of Heart Failure

    E-Print Network [OSTI]

    Morrell, Christopher H.

    Heart Failure Cardiovascular Features of Heart Failure With Preserved Ejection Fraction Versus of patients with heart failure with preserved ejection fraction (HFpEF) that differ from those in individuals failure. Background Heart failure with preserved ejection fraction often develops in HLVH patients

  15. Brittle film-induced cracking of ductile substrates , Lijie Qiao a,

    E-Print Network [OSTI]

    Volinsky, Alex A.

    Brittle film-induced cracking of ductile substrates Tao Guo a , Lijie Qiao a, , Xiaolu Pang b 29 May 2015 Revised 22 July 2015 Accepted 23 July 2015 Keywords: Brittle film Ductile substrate Film-induced cracking Dislocations Crack velocity a b s t r a c t Film and substrate mechanical integrity is essential

  16. Measurement of the adhesion of a brittle film on a ductile substrate by indentation

    E-Print Network [OSTI]

    Hutchinson, John W.

    Measurement of the adhesion of a brittle film on a ductile substrate by indentation BY M. D. DRORY1 is analysed for obtaining the interfacetoughness. This measurementmethod of adhesion provides a simple be present. The aspect of film reliability explored here is the measurementof adhesion for brittle coatings

  17. Brittle Fault Chronology of New York City (NYC) Charles Merguerian, Geology Department, Hofstra University, Hempstead, NY 11549

    E-Print Network [OSTI]

    Merguerian, Charles

    Brittle Fault Chronology of New York City (NYC) Charles Merguerian, Geology Department, Hofstra This Abstract: Merguerian, Charles, 2004a, Brittle fault chronology of New York City (NYC): Geological Society

  18. Approved Module Information for ME2F21, 2014/5 Module Title/Name: Material Technology Module Code: ME2F21

    E-Print Network [OSTI]

    Rebollo-Neira, Laura

    :Elasticity, Plasticity, Stress/time temperature effects, Stiffness and buckling, Fracture toughness, Hardness, Fatigue stress (brittle/ductile) ?uts, Buckling: elastic and plastic instability Brittle fractures and; stress service loading forces and stresses and environmental exposure, Ductile failures ?y Ultimate tensile

  19. A scalable computational approach for modeling dynamic fracture of brittle solids in three dimensions

    E-Print Network [OSTI]

    Seagraves, Andrew Nathan

    2010-01-01

    In this thesis a new parallel computational method is proposed for modeling threedimensional dynamic fracture of brittle solids. The method is based on a combination of the discontinuous Galerkin (DG) formulation of the ...

  20. Definition of the Brittle-Ductile Transition in the Coso Geothermal...

    Open Energy Info (EERE)

    Definition of the Brittle-Ductile Transition in the Coso Geothermal Field East-Central California USA Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  1. MARS OBSERVER Mission Failure

    E-Print Network [OSTI]

    Rhoads, James

    of Mars Observer Mission Failure.. ................... D-12 a. Most Probable Cause: Leakage of NT0 Through Check Valves .................................................................. D-14 b. Potential Cause: Pressure Regulator Failure....................... D-28 c. Potential Cause: Failure of a Pyro Valve Charge

  2. Stability maps to predict anomalous ductility in B2 materials

    E-Print Network [OSTI]

    Sun, Ruoshi

    While most B2 materials are brittle, a new class of B2 (rare-earth) intermetallic compounds is observed to have large ductility. We analytically derive a necessary condition for ductility (dislocation motion) involving ...

  3. An Experimental Study of Deformation and Fracture of a Nanostructured Metallic Material 

    E-Print Network [OSTI]

    Abdel Al, Nisrin Rizek

    2011-02-22

    , the mechanical behavior of a nanostructured, nearly pure material is investigated in order to link processing conditions, microstructure, and fracture locus in stress space. With focus laid on BCC materials which can undergo a ductile-to-brittle transition...

  4. Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion toMSDS onBudgetMaterialMaterials Materials Access to

  5. Progressive Collapse Mechanisms of Brittle and Ductile Framed Structures

    E-Print Network [OSTI]

    Enrico Masoero; Falk K. Wittel; Hans J. Herrmann; B. M. Chiaia

    2015-09-07

    In this paper, we study the progressive collapse of 3D framed structures made of reinforced concrete after the sudden loss of a column. The structures are represented by elasto-plastic Euler Bernoulli beams with elongation-rotation failure threshold. We performed simulations using the Discrete Element Method considering inelastic collisions between the structural elements. The results show what collapse initiation and impact-driven propagation mechanisms are activated in structures with different geometric and mechanical features. Namely, we investigate the influence of the cross sectional size and reinforcement $\\alpha$ and of the plastic capacity $\\beta$ of the structural elements. We also study the final collapse extent and the fragment size distribution and their relation to $\\alpha$, $\\beta$ and to the observed collapse mechanisms. Finally, we compare the damage response of structures with symmetric and asymmetric reinforcement in the beams.

  6. BRITTLE FRACTURE IN HEAT-AFFECTED ZONES OF GIRTH WELDS OF MODERN LINE PIPE STEEL (X100)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    BRITTLE FRACTURE IN HEAT-AFFECTED ZONES OF GIRTH WELDS OF MODERN LINE PIPE STEEL (X100) A.-S. BILAT welds of modern line pipe steel, such as X100, issued from a pulsed automatic gas metal arc welding). The brittle zone is located in the coarse-grained heat-affected zone of the weld. The reproduction of two heat

  7. Method of determining elastic and plastic mechanical properties of ceramic materials using spherical indenters

    DOE Patents [OSTI]

    Adler, Thomas A. (Corvallis, OR)

    1996-01-01

    The invention pertains a method of determining elastic and plastic mechanical properties of ceramics, intermetallics, metals, plastics and other hard, brittle materials which fracture prior to plastically deforming when loads are applied. Elastic and plastic mechanical properties of ceramic materials are determined using spherical indenters. The method is most useful for measuring and calculating the plastic and elastic deformation of hard, brittle materials with low values of elastic modulus to hardness.

  8. Radon emanation from brittle fracturing in granites under upper crustal conditions

    E-Print Network [OSTI]

    Nicolas, Chamot-Rooke

    Radon emanation from brittle fracturing in granites under upper crustal conditions Aurélien Nicolas CEA, DAM, DIF, Arpajon, France Abstract Radon-222, a radioactive gas naturally produced in the Earth precursor. Here we investigate the effects of mechanical and thermal damage on the radon emanation from

  9. Experimental study of the transition from brittle shear fractures to joints 

    E-Print Network [OSTI]

    Ramsey, Jonathan Michael

    2003-01-01

    Current geologic thinking is that there are two, and only two, distinct types of brittle fractures, joints and shear fractures (faults). For over half a century, it has been debated that a third type of fracture, referred to as hybrid fractures...

  10. STRATIGRAPHY, STRUCTURAL GEOLOGY, AND DUCTILE-AND BRITTLE FAULTS OF NEW YORK CITY

    E-Print Network [OSTI]

    Merguerian, Charles

    STRATIGRAPHY, STRUCTURAL GEOLOGY, AND DUCTILE- AND BRITTLE FAULTS OF NEW YORK CITY Charles in the 1800's and 1900's, the bedrock geology of the New York City area was mapped in systematic detail author of the United States Geological Survey New York City Folio (#83) published in 1902, outlined

  11. Measurement of the ductile to brittle transition temperature for waste tank cooling coils

    SciTech Connect (OSTI)

    Wiersma, B.J.

    1992-09-01

    Charpy impact tests were conducted on ASTM A106 carbon steel archived from SRS waste tanks to determine the susceptibility of the cooling coils to brittle fracture during a seismic event. The highest ductile to brittle transition temperature measured was {minus}5{degree}F and, with the addition of a 30{degree}F safety factor, the minimum safe operating temperature was determined to be 25{degree}F. Calculations also showed that a pre-existing circumferential flaw that is 2.2in. long would be necessary to initiate brittle fracture of the pipe. These results demonstrate that the pipes will not be susceptible to brittle fracture if the cooling water inlet temperature is lowered to 50{degree}F. Visual observation of the inner and outer walls of the pipe showed no localized attack or significant wall thinning. A 100--200 micron zinc coating is probably the reason for the lack of corrosion. A build-up of zinc slag occurred at pipe fittings where the weld had burned through. Although no attack was observed, the slag created several crevices which have the potential to trap the chromated water and initiate localized attack.

  12. Measurement of the ductile to brittle transition temperature for waste tank cooling coils

    SciTech Connect (OSTI)

    Wiersma, B.J.

    1992-09-01

    Charpy impact tests were conducted on ASTM A106 carbon steel archived from SRS waste tanks to determine the susceptibility of the cooling coils to brittle fracture during a seismic event. The highest ductile to brittle transition temperature measured was [minus]5[degree]F and, with the addition of a 30[degree]F safety factor, the minimum safe operating temperature was determined to be 25[degree]F. Calculations also showed that a pre-existing circumferential flaw that is 2.2in. long would be necessary to initiate brittle fracture of the pipe. These results demonstrate that the pipes will not be susceptible to brittle fracture if the cooling water inlet temperature is lowered to 50[degree]F. Visual observation of the inner and outer walls of the pipe showed no localized attack or significant wall thinning. A 100--200 micron zinc coating is probably the reason for the lack of corrosion. A build-up of zinc slag occurred at pipe fittings where the weld had burned through. Although no attack was observed, the slag created several crevices which have the potential to trap the chromated water and initiate localized attack.

  13. THE DYNAMICS OF RAPIDLY MOVING TENSILE CRACKS IN BRITTLE AMORPHOUS MATERIAL

    E-Print Network [OSTI]

    Fineberg, Jay

    initiated during the second World War. These theories generalized the concept of energy balance, which, and a corresponding sharp increase of the fracture energy with the mean crack velocity. We present experimental occurs when the potential elastic energy per unit area released by a unit extension of a crack is equal

  14. Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJesse BergkampCentermillion toMSDS onBudgetMaterial

  15. SYNTHETIC SLING FAILURE - EVALUATIONS & RECOMMENDATIONS

    SciTech Connect (OSTI)

    MACKEY TC; HENDERSON CS

    2009-10-26

    The information and evaluations provided in this report were compiled to address the recurring problem of synthetic sling failure. As safety is the number one priority in all work aspects, a solution must be devised to prevent accidents from occurring. A total of thirteen cases regarding synthetic sling failure were evaluated in order to determine their causes, effects, and preventative measures. From the collected data, it was found that all cases in which the synthetic sling contacted the edge of its load resulted in sling failure. It is required that adequate synthetic sling protection devices be used to protect slings in any lift where the sling comes in direct contact with the edge or corner of its load. However, there are no consensus codes or standards stating the type, material, or purpose of the type of protective device used to protect the sling from being cut. Numerous industry standards and codes provide vague descriptions on how to protect synthetic slings. Without a clear, concise statement of how to protect synthetic slings, it is common for inadequate materials and sling protection devices to be used in an attempt to meet the intent of these requirements. The use of an inadequate sling protection device is the main cause of synthetic sling failure in all researched cases. Commercial sling protection devices come in many shapes and sizes, and have a variety of names, as well as advertised uses. 'Abrasion pads' and 'wear protectors' are two different names for products with the same intended purpose. There is no distinguishable way to determine the extent of sling protection which these devices will provide, or what specific scenarios they are made for. This creates room for error in a field where error is unacceptable. This report provides a recommended action for hoisting and rigging activities which require synthetic slings to contact a load, as well as recommended changes to industry standards which will benefit overall industry safety.

  16. Failure mechanisms in MEMS.

    SciTech Connect (OSTI)

    Walraven, Jeremy Allen

    2003-07-01

    MEMS components by their very nature have different and unique failure mechanisms than their macroscopic counterparts. This paper discusses failure mechanisms observed in various MEMS components and technologies. MEMS devices fabricated using bulk and surface micromachining process technologies are emphasized. MEMS devices offer uniqueness in their application, fabrication, and functionality. Their uniqueness creates various failure mechanisms not typically found in their bulk or IC counterparts. In ICs, electrical precautions are taken to mitigate failure. In MEMS, both electrical and mechanical precautions must be enacted to reduce the risk of failure and increased reliability. Unlike ICs, many MEMS components are designed to interact with their environment, making the fabrication, testing, and packaging processes critical for the success of the device.

  17. Single crystal silicon as a macro-world structural material : application to compact, lightweight high pressure vessels

    E-Print Network [OSTI]

    Garza, Tanya Cruz

    2011-01-01

    Single crystal silicon has promising inherent structural properties which are attractive for weight sensitive applications. Single crystal silicon, however, is a brittle material which makes the usable strength that can ...

  18. Research News Structured Porous Materials via Colloidal

    E-Print Network [OSTI]

    Velev, Orlin D.

    to Metals** By Orlin D. Velev* and Eric W. Kaler The formation of nanostructured materials by using applications in optical information processing and storage, advanced coatings, catalysis, and other emerging, dried colloidal crystals are very brittle and may disperse in water. Any practical device thus requires

  19. NO. IRIEV. NC LSG Single Point Failure

    E-Print Network [OSTI]

    Rathbun, Julie A.

    of high reliability component parts and accepted materials, and by the use of highly reliability design scientific data will be lost (tidal, lunar free oscillation, lunar seismic activity, and the drift 4 DATE 5/18/71 7. Seismic Amplifier and Filter - Failure will result in inability to accept

  20. Markus J. Buehler Materials and Process Simulation Center (MSC)

    E-Print Network [OSTI]

    Goddard III, William A.

    mechanics engineering scale Supersonic fracture (Buehler et al.) cohesive laws energy flow #12;"brittle-technologies (N/MEMS), bio- inspired materials and technologies (e.g. artificial silk based materials, new smart volume) #12;Outline Motivation (previous slides): From small to large Introduction: Multi-scale multi

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

    SciTech Connect (OSTI)

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

    2005-01-11

    It has been established that microelectromechanical systems (MEMS) created from polycrystalline silicon thin-films are subject to cyclic fatigue. Prior work by the authors has suggested that although bulk silicon is not susceptible to fatigue failure in ambient air, fatigue in micron-scale silicon is a result of a ''reaction-layer'' process, whereby high stresses induce a thickening of the post-release oxide at stress concentrations such as notches, which subsequently undergoes moisture-assisted cracking. However, there exists some controversy regarding the post-release oxide thickness of the samples used in the prior study. In this Letter, we present data from devices from a more recent fabrication run that confirm our prior observations. Additionally, new data from tests in high vacuum show that these devices do not fatigue when oxidation and moisture are suppressed. Each of these observations lends credence to the '''reaction-layer'' mechanism. Recent advances in the design of microelectromechanical systems (MEMS) have increased the demand for more reliable microscale structures. Although silicon is an effective and widely used structural material at the microscale, it is very brittle. Consequently, reliability is a limiting factor for commercial and defense applications. Since the surface to volume ratio of these structural films is very large, classical models for failure modes in bulk materials cannot always be applied. For example, whereas bulk silicon is immune to cyclic fatigue failure thin micron-scale structural films of silicon appear to be highly susceptible. It is clear that at these size scales, surface effects may become dominant in controlling mechanical properties. The main reliability issues for MEMS are stiction, fatigue and wear. Fatigue is important in cases where devices are subjected to a large number of loading cycles with amplitudes below their (single-cycle) fracture stress, which may arise due to vibrations intentionally induced in the structure (i.e. a resonator) or those which arise from the service environment. While the reliability of MEMS has received extensive attention, the physical mechanisms responsible for these failure modes have yet to be conclusively determined. This is particularly true for fatigue, where the mechanisms have been subject to intense debate. Recently we have proposed that the fatigue of micron-scale polysilicon is associated with stress-induced surface oxide thickening and moisture-assisted subcritical cracking in the amorphous SiO{sub 2} oxide layer (''reaction-layer'' fatigue). The mechanism of oxide thickening is as yet unknown, but is likely related to some form of stress-assisted diffusion. Allameh et al. suggest a complementary mechanism involving stress-assisted oxide thickening, caused by dissolution of the surface oxide which forms deep grooves that are sites for crack initiation. Kahn et al. have criticized these mechanisms and proposed that, instead, fatigue is caused by subcritical cracking due to contacting surface asperities in the compressive part of the cycle. To the authors' knowledge, there is no direct experimental observation of such asperity contact. Also, their model cannot explain why micron-scale silicon, and not bulk silicon, is susceptible to fatigue. Moreover, Kahn et al. do not acknowledge the role of stress-induced oxide thickening, which has been observed directly using TEM and indirectly using atomic-force microscope measurements by several investigators, and have questioned whether the materials utilized by Muhlstein et al. and Allameh et al. were representative due to the relatively thick oxide scales. Accordingly, the goal of the present research is to seek a definitive understanding of the physical mechanisms responsible for fatigue in polysilicon structural thin-films. Our approach is to combine on-chip testing methods with electron microscopy by fatiguing thin-film samples and observing them, in an unthinned condition, using high-voltage transmission electron microscopy (HVTEM). Two principal results are found from this work: (1

  2. Weld failure detection

    DOE Patents [OSTI]

    Pennell, William E. (Unity Township, Westmoreland County, PA); Sutton, Jr., Harry G. (Mt. Lebanon, PA)

    1981-01-01

    Method and apparatus for detecting failure in a welded connection, particrly applicable to not readily accessible welds such as those joining components within the reactor vessel of a nuclear reactor system. A preselected tag gas is sealed within a chamber which extends through selected portions of the base metal and weld deposit. In the event of a failure, such as development of a crack extending from the chamber to an outer surface, the tag gas is released. The environment about the welded area is directed to an analyzer which, in the event of presence of the tag gas, evidences the failure. A trigger gas can be included with the tag gas to actuate the analyzer.

  3. Fracture initiation by local brittle zones in weldments of quenched and tempered structural alloy steel plate

    SciTech Connect (OSTI)

    Kenney, K.L.; Reuter, W.G.; Reemsnyder, H.S.; Matlock, D.K.

    1997-12-31

    The heat-affected zone (HAZ) embrittlement of an API 2Y Grade 50T quenched and tempered offshore structural steel plate, welded by the submerged-arc process at a heat input of 4.5 kJ/mm, was investigated from the viewpoint of identifying the local brittle zone (LBZ) microstructure and the metallurgical factors associated with its formation. Microstructural and fractographic analysis showed the LBZ microstructure to be dual phase martensite-austenite (M-A) constituent. The formation of M-A constituent was found to be related to microstructural banding of the hot-rolled base plate. When the banded base plate was welded, M-A constituent formed only within the band microstructure which penetrated the intercritically-reheated coarse-grain HAZ (IRCGHAZ). The chemistry of the band microstructure in conjunction with the thermal cycle of the IRCGHAZ provided the critical conditions for the formation of M-A constituent in the API 2Y Grade 50T steel investigated. The influence of local brittle zones (i.e., M-A constituent) on the HAZ fracture toughness was evaluated by means of Crack-Tip Opening Displacement (CTOD) tests. These tests showed the steel to suffer embrittlement when the fatigue precrack sampled an intercritically-reheated coarse-grain HAZ which contained M-A constituent, confirming that M-A constituent is the major microstructural factor controlling the HAZ toughness of this particular steel.

  4. Brittle fracture in a periodic structure with internal potential energy. Spontaneous crack propagation

    E-Print Network [OSTI]

    Mark Ayzenberg-Stepanenko; Gennady Mishuris; Leonid Slepyan

    2014-02-12

    Spontaneous brittle fracture is studied based on the recently introduced model (Mishuris and Slepyan, Brittle fracture in a periodic structure with internal potential energy. Proc. Roy. Soc. A, in press). A periodic structure is considered, where only the prospective crack-path layer is specified as a discrete set of alternating initially stretched and compressed bonds. A bridged crack destroying initially stretched bonds may propagate under a certain level of the internal energy without external sources. The general analytical solution with the crack speed $-$ energy relation is presented in terms of the crack-related dynamic Green's function. For the anisotropic two-line chain and lattice considered earlier in quasi-statics, the dynamic problem is examined in detail. The crack speed is found to grow unboundedly as the energy approaches its upper limit. It is revealed that the spontaneous fracture can occur in the form of a pure bridged, partially bridged or fully open crack depending on the internal energy level. Generally, the steady-state mode of the crack propagation is found to be realised, whereas an irregular growth, clustering and the crack speed oscillations are detected in a vicinity of the lower bound of the energy.

  5. Better Bearing Housing Seals Prevent Costly Machinery Failures 

    E-Print Network [OSTI]

    Bloch, H. P.

    1993-01-01

    of these failures could be prevented through the use of appropriately engineered, properly selected, and suitably installed bearing housing seals. Associated savings in labor, materials, and energy would accrue due to extended oil change intervals and a portion...

  6. Characterization and detection of incipient underground cable failures 

    E-Print Network [OSTI]

    Chaturbedi, Ritesh

    2002-01-01

    For distribution systems, failure of an underground cable results in an unscheduled outage. An unscheduled outage costs a utility manpower and materials, and affects their reliability index. Thus, the need for an on-line, ...

  7. Synergistic failure of BWR internals

    SciTech Connect (OSTI)

    A. G. Ware; T. Y. Chang

    1999-10-25

    Boiling Water Reactor (BWR) core shrouds and other reactor internals important to safety are experiencing intergranular stress corrosion cracking (IGSCC). The United States Nuclear Regulatory Commission has followed the problem, and as part of its investigations, contracted with the Idaho National Engineering and Environmental Laboratory to conduct a risk assessment. The overall project objective is to assess the potential consequences and risks associated with the failure of IGSCC-susceptible BWR vessel internals, with specific consideration given to potential cascading and common mode effects. An initial phase has been completed in which background material was gathered and evaluated, and potential accident sequences were identified. A second phase is underway to perform a simplified, quantitative probabilistic risk assessment on a representative high-power BWR/4. Results of the initial study conducted on the jet pumps show that any cascading failures would not result in a significant increase in the core damage frequency. The methodology is currently being extended to other major reactor internals components.

  8. Synergistic Failure of BWR Internals

    SciTech Connect (OSTI)

    Ware, Arthur Gates; Chang, T-Y

    1999-10-01

    Boiling Water Reactor (BWR) core shrouds and other reactor internals important to safety are experiencing intergranular stress corrosion cracking (IGSCC). The United States Nuclear Regulatory Commission has followed the problem, and as part of its investigations, contracted with the Idaho National Engineering and Environmental Laboratory to conduct a risk assessment. The overall project objective is to assess the potential consequences and risks associated with the failure of IGSCC-susceptible BWR vessel internals, with specific consideration given to potential cascading and common mode effects. An initial phase has been completed in which background material was gathered and evaluated, and potential accident sequences were identified. A second phase is underway to perform a simplified, quantitative probabilistic risk assessment on a representative high-power BWR/4. Results of the initial study conducted on the jet pumps show that any cascading failures would not result in a significant increase in the core damage frequency. The methodology is currently being extended to other major reactor internals components.

  9. Salt diapirism with simultaneous brittle faulting and viscous flow ALEXEI N. B. POLIAKOV1-2,YURIYU. PODLADCHIKOV3, ETHAN CH. DAWSON4 &

    E-Print Network [OSTI]

    Podladchikov, Yuri

    Salt diapirism with simultaneous brittle faulting and viscous flow ALEXEI N. B. POLIAKOV1-2,YURIYU for the fxst time how sedimentaryrocks above a salt diapir can deform in either a brittle or a viscous way depending on the stress state and strain rates. Most existing models for salt tectonics incorporate only one

  10. “Playboy Bunny” Sign of Congestive Heart Failure

    E-Print Network [OSTI]

    Hokama, Akira; Arakaki, Shingo; Shibata, Daisuke; Maeshiro, Tatsuji; Kinjo, Fukunori; Fujita, Jiro

    2011-01-01

    Bunny’’ Sign of Congestive Heart Failure Akira Hokama, MD*to evaluate congestive heart failure. We highlight ‘‘Playboycaused by congestive heart failure. [West J Emerg Med. 2011;

  11. Combination stem cell therapy for heart failure

    E-Print Network [OSTI]

    2010-01-01

    to further analyze his heart failure. Com- plete bloodA: Inflammatory markers in stable heart failure and theirof improvement and readmission in heart failure. Eur J Heart

  12. LEWIS SPACECRAFT MISSION FAILURE INVESTIGATION BOARD

    E-Print Network [OSTI]

    Rhoads, James

    LEWIS SPACECRAFT MISSION FAILURE INVESTIGATION BOARD FINAL REPORT 12 February 1998 #12;II #12;III LEWIS SPACECRAFT MISSION FAILURE INVESTIGATION BOARD REPORT TABLE OF CONTENTS TOPIC PAGE EXECUTIVE Spacecraft Flight Operations and Failure Anomaly Timeline FACTORS DIRECTLY CONTRIBUTING TO FAILURE

  13. Merguerian, Charles, 1994a, Stratigraphy, structural geology, and ductile-and brittle faults of the New York City area, p. 49-56 in Hanson, G. N., chm., Geology of Long Island

    E-Print Network [OSTI]

    Merguerian, Charles

    Merguerian, Charles, 1994a, Stratigraphy, structural geology, and ductile- and brittle faults with Abstracts, 165 p. STRATIGRAPHY, STRUCTURAL GEOLOGY, AND DUCTILE- AND BRITTLE FAULTS OF THE NEW YORK CITY of the stratigraphy and structure of the region and has delineated a number of ductile- and brittle faults. The belt

  14. Geometric control of failure behavior in perforated sheets

    E-Print Network [OSTI]

    Michelle M. Driscoll

    2014-11-20

    Adding perforations to a continuum sheet allows new modes of deformation, and thus modifies its elastic behavior. The failure behavior of such a perforated sheet is explored, using a model experimental system: a material containing a one-dimensional array of rectangular holes. In this model system, a transition in failure mode occurs as the spacing and aspect ratio of the holes are varied: rapid failure via a running crack is completely replaced by quasi-static failure which proceeds via the breaking of struts at random positions in the array of holes. I demonstrate that this transition can be connected to the loss of stress enhancement which occurs as the material geometry is modified.

  15. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 1 Fracturing Rigid Materials

    E-Print Network [OSTI]

    Thrun, Sebastian

    IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 1 Fracturing Rigid Materials Zhaosheng Bao to fracturing (and denting) brittle materials. To avoid the computational burden imposed by the stringent time mesh upon which finite element analysis can be carried out to provide a stress map for fracture

  16. Porosity in hybrid materials

    SciTech Connect (OSTI)

    Schaefer, D.W.; Beaucage, G.; Loy, D. [Sandia National Labs., Albuquerque, NM (United States)

    1995-12-31

    Multicomponent, or hybrid composites are emerging as precursors to porous materials. Sacrifice of an ephemeral phase can be used to generate porosity, the nature of which depends on precursor structure. Retention of an organic constituent, on the other hand, can add desirable toughness to an otherwise brittle ceramic. We use small-angle x-ray and neutron scattering to examine porosity in both simple and hybrid materials. We find that microphase separation controls porosity in almost all systems studied. Pore distributions are controlled by the detailed bonding within and between phases as well as the flexibility of polymeric constituents. Thus hybridization opens new regions of pore distributions not available in simple systems. We look at several sacrificial concepts and show that it is possible to generate multimodal pore size distributions due to the complicated phase structure in the precursor.

  17. 3.22 Mechanical Properties of Materials, Spring 2003

    E-Print Network [OSTI]

    Gibson, Lorna J.

    Phenomenology of mechanical behavior of materials at the macroscopic level. Relationship of mechanical behavior to material structure and mechanisms of deformation and failure. Topics include: elasticity, viscoelasticity, ...

  18. 3.22 Mechanical Properties of Materials, Spring 2004

    E-Print Network [OSTI]

    Gibson, Lorna J.

    Phenomenology of mechanical behavior of materials at the macroscopic level. Relationship of mechanical behavior to material structure and mechanisms of deformation and failure. Topics include: elasticity, viscoelasticity, ...

  19. Hybrid sol-gel optical materials

    DOE Patents [OSTI]

    Zeigler, John M. (Albuquerque, NM)

    1992-01-01

    Hybrid sol-gel materials comprise silicate sols cross-linked with linear polysilane, polygermane, or poly(silane-germane). The sol-gel materials are useful as optical identifiers in tagging and verification applications and, in a different aspect, as stable, visible light transparent non-linear optical materials. Methyl or phenyl silicones, polyaryl sulfides, polyaryl ethers, and rubbery polysilanes may be used in addition to the linear polysilane. The linear polymers cross-link with the sol to form a matrix having high optical transparency, resistance to thermooxidative aging, adherence to a variety of substrates, brittleness, and a resistance to cracking during thermal cycling.

  20. Hybrid sol-gel optical materials

    DOE Patents [OSTI]

    Zeigler, J.M.

    1993-04-20

    Hybrid sol-gel materials comprise silicate sols cross-linked with linear polysilane, polygermane, or poly(silane-germane). The sol-gel materials are useful as optical identifiers in tagging and verification applications and, in a different aspect, as stable, visible light transparent non-linear optical materials. Methyl or phenyl silicones, polyaryl sulfides, polyaryl ethers, and rubbery polysilanes may be used in addition to the linear polysilane. The linear polymers cross-link with the sol to form a matrix having high optical transparency, resistance to thermooxidative aging, adherence to a variety of substrates, brittleness, and a resistance to cracking during thermal cycling.

  1. Hybrid sol-gel optical materials

    DOE Patents [OSTI]

    Zeigler, John M. (Albuquerque, NM)

    1993-01-01

    Hybrid sol-gel materials comprise silicate sols cross-linked with linear polysilane, polygermane, or poly(silane-germane). The sol-gel materials are useful as optical identifiers in tagging and verification applications and, in a different aspect, as stable, visible light transparent non-linear optical materials. Methyl or phenyl silicones, polyaryl sulfides, polyaryl ethers, and rubbery polysilanes may be used in addition to the linear polysilane. The linear polymers cross-link with the sol to form a matrix having high optical transparency, resistance to thermooxidative aging, adherence to a variety of substrates, brittleness, and a resistance to cracking during thermal cycling.

  2. Thermal Cycling on Fatigue Failure of the Plutonium Vitrification Melter

    SciTech Connect (OSTI)

    Jordan, Jeffrey; Gorczyca, Jennifer

    2009-02-11

    One method for disposition of excess plutonium is vitrification into cylindrical wasteforms. Due to the hazards of working with plutonium, the vitrification process must be carried out remotely in a shielded environment. Thus, the equipment must be easily maintained. With their simple design, induction melters satisfy this criterion, making them ideal candidates for plutonium vitrification. However, due to repeated heating and cooling cycles and differences in coefficients of thermal expansion of contacting materials fatigue failure of the induction melter is of concern. Due to the cost of the melter, the number of cycles to failure is critical. This paper presents a method for determining the cycles to failure for an induction melter by using the results from thermal and structural analyses as input to a fatigue failure model.

  3. FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

    2007-04-30

    Thermal stresses and warpage of the PEN are unavoidable due to the temperature changes from the stress-free sintering temperature to room temperature and mismatch of the coefficients of thermal expansion (CTE) of various layers in the PEN structures of solid oxide fuel cells (SOFC) during the PEN manufacturing process. In the meantime, additional mechanical stresses will also be created by mechanical flattening during the stack assembly process. The porous nature of anode and cathode in the PEN structures determines presence of the initial flaws and crack on the interfaces of anode/electrolyte/cathode and in the interior of the materials. The sintering/assembling induced stresses may cause the fracture failure of PEN structure. Therefore, fracture failure criteria for SOFC PEN structures is developed in order to ensure the structural integrity of the cell and stack of SOFC. In this paper, the fracture criteria based on the relationship between the critical energy release rate and critical curvature and maximum displacement of the warped cells caused by the temperature changes as well as mechanical flattening process is established so that possible failure of SOFC PEN structures may be predicted deterministically by the measurement of the curvature and displacement of the warped cells.

  4. Failure Inferencing based Fast Rerouting for Handling Transient Link and Node Failures

    E-Print Network [OSTI]

    Nelakuditi, Srihari

    generation, propagation, and processing mechanisms. MPLS based approaches [5] handle transient failures1 Failure Inferencing based Fast Rerouting for Handling Transient Link and Node Failures Zifei network with high service availability. Unfortunately, in today's Internet, transient failures occur

  5. Autonomous thruster failure recovery for underactuated spacecraft

    E-Print Network [OSTI]

    Pong, Christopher Masaru

    2010-01-01

    Thruster failures historically account for a large percentage of failures that have occurred on orbit. Therefore, autonomous thruster failure detection, isolation, and recovery (FDIR) is an essential component to any robust ...

  6. Brittle-to-Ductile Transition in Uniaxial Compression of Silicon Pillars at Room Temperature

    E-Print Network [OSTI]

    Ballarini, Roberto

    , one of the holy grails of the materials science and ceramics communities has remained elusive. A half

  7. An Estimator of Propagation of Cascading Failure

    SciTech Connect (OSTI)

    Dobson, Ian; Wierzbicki, Kevin; Carreras, Benjamin A; Lynch, Vickie E; Newman, David E

    2006-01-01

    The authors suggest a statistical estimator to measure the extent to which failures propagate in cascading failures such as large blackouts.

  8. Failure analysis issues in microelectromechanical systems (MEMS...

    Office of Scientific and Technical Information (OSTI)

    Conference: Failure analysis issues in microelectromechanical systems (MEMS). Citation Details In-Document Search Title: Failure analysis issues in microelectromechanical systems...

  9. The influence of coarse aggregate size and volume on the fracture behavior and brittleness of self-compacting concrete

    SciTech Connect (OSTI)

    Beygi, Morteza H.A.; Kazemi, Mohammad Taghi; Nikbin, Iman M.; Vaseghi Amiri, Javad; Rabbanifar, Saeed; Rahmani, Ebrahim

    2014-12-15

    This paper presents the results of an experimental investigation on fracture characteristics and brittleness of self-compacting concrete (SCC), involving the tests of 185 three point bending beams with different coarse aggregate size and content. Generally, the parameters were analyzed by the work of fracture method (WFM) and the size effect method (SEM). The results showed that with increase of size and content of coarse aggregate, (a) the fracture energy increases which is due to the change in fractal dimensions, (b) behavior of SCC beams approaches strength criterion, (c) characteristic length, which is deemed as an index of brittleness, increases linearly. It was found with decrease of w/c ratio that fracture energy increases which may be explained by the improvement in structure of aggregate-paste transition zone. Also, the results showed that there is a correlation between the fracture energy measured by WFM (G{sub F}) and the value measured through SEM (G{sub f}) (G{sub F} = 3.11G{sub f})

  10. A simple approach to modeling ductile failure.

    SciTech Connect (OSTI)

    Wellman, Gerald William

    2012-06-01

    Sandia National Laboratories has the need to predict the behavior of structures after the occurrence of an initial failure. In some cases determining the extent of failure, beyond initiation, is required, while in a few cases the initial failure is a design feature used to tailor the subsequent load paths. In either case, the ability to numerically simulate the initiation and propagation of failures is a highly desired capability. This document describes one approach to the simulation of failure initiation and propagation.

  11. ynamic fracture occupies a peculiar niche in the study of materials. One of

    E-Print Network [OSTI]

    Texas at Austin. University of

    D ynamic fracture occupies a peculiar niche in the study of materials. One of the first things, scientists and engineers studying fracture mechanics focus on determining the critical con- ditions, created, and picoseconds to microseconds, so as to compare theory and experiment for brittle fracture. Strip fracture One

  12. Role of microbial induced corrosion in subsea water pipeline failure

    SciTech Connect (OSTI)

    Samant, A.K.; Singh, S.K.

    1998-12-31

    Premature failure of subsea water injection pipelines due to rupture was observed in Indian offshore facilities. In this connection various contributing factors like metallurgy of pipeline, operating conditions and corrosion related parameters have been examined. Material defects that can lead to premature failure of pipelines like microstructural anomalies, variation in hardness and elemental composition and tensile strength etc. have been found within the specified limits of material specification. Analysis of various operating parameters and water quality data indicated failure due to microbial induced internal corrosion. Due to low flow velocities, suspended insoluble corrosion products, bacteria and other microbes, present in the water, accumulated inside the pipeline surface mostly in low areas. Deposit provided hiding place for bacteria and shielded them from effective treatment by bactericide. Deposits also resulted in the formation of oxygen concentration cells resulting in localized corrosion. Non-pigging of pipe lines, even after long shut down, also resulted in accumulation of deposits. During this period, microbial activities dominated resulting in the formation of acidic metabolizes which ultimately led to internal corrosion. In this paper, all above aspects have been examined with special reference to the role of microbiologically induced corrosion for failure of subsea water injection pipe lines.

  13. Enyinruiny Frwturr Mec~hunics. IY70. Vol. I, pp, 577-602. Pergamon Preu. Printed in Great Britain PLASTIC DEFORMATION IN BRITTLE AND

    E-Print Network [OSTI]

    PLASTIC DEFORMATION IN BRITTLE AND DUCTILE FRACTURE? D. C. DRUCKERf and J. R. RICE5 Divisionof Engineering, Brown University, Providence, R.I. 02911, U.S.A. Abstract-An effort is made to cover the full elastic-plastic at fully plastic or limit load conditions. Similarities and differences of behavior between steels which

  14. Gradient damage models and their use to approximate brittle fracture Kim Phama,b, Hanen Amorc,, Jean-Jacques Marigod, Corrado Maurinia,b,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Gradient damage models and their use to approximate brittle fracture Kim Phama,b, Hanen Amorc of gradient damage models. In the present paper, we first formulate the quasi-static evolution problem of damage. These concepts are applied in the particular setting of a one-dimensional traction test

  15. Failure of Tapo Canyon Tailings Dam

    E-Print Network [OSTI]

    Harder, Leslie F Jr; Stewart, Jonathan P

    1996-01-01

    failures of Chilean tailings dams." J. Soil Mech. and Found.earthquake failure of a tailings dam due to liquefaction offailure of the Tapo Canyon tailings dam was one of the most

  16. Individual Reactions to Failure in Virtual Teams 

    E-Print Network [OSTI]

    Diaz, Ismael

    2012-02-14

    This project examines the relationship between team identification and collaboration configuration and how they affect attributions to failure. In a sample of 110 participants, we examined reactions to failure. We manipulated perceptions...

  17. Introduction to Microelectromechanical Systems (MEMS) failure...

    Office of Scientific and Technical Information (OSTI)

    Conference: Introduction to Microelectromechanical Systems (MEMS) failure analysis. Citation Details In-Document Search Title: Introduction to Microelectromechanical Systems (MEMS)...

  18. Winning the fight against boiler tube failure

    SciTech Connect (OSTI)

    Cohen, J.; Dooley, B.

    1986-12-01

    Eliminating boiler tube failures could be worth $5 billion a year to the electric power industry. The causes and cures for the great majority of these ubiquitous failures are now known, with implications for change ranging from senior management to the maintenance crew. Methods for preventing boiler tube failure are discussed.

  19. Failure by fracture and fatigue in "NANO" and "BIO" materials

    E-Print Network [OSTI]

    Ritchie, R.O.; Muhlstein, C.L.; Nalla, R.K.

    2003-01-01

    structures for microelectromechanical systems (MEMS), andstructures for microelectromechanical systems (MEMS),

  20. Real-Time Quantitative Imaging of Failure Events in Materials...

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

    25 March 2013 00:00 Gathering information on the evolution of small cracks in ceramic matrix composites used in hostile environments such as in gas turbines and hypersonic flights...

  1. Global Failure Criteria for SOFC Positive/Electrolyte/Negative (PEN) Structure

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

    2007-04-01

    Due to the mismatch of thermal expansion coefficients (TEC) of the various layer materials in SOFC, the internal stresses are unavoidable under temperature differential. In order to create the reliable cell and stack of solid oxide fuel cell (SOFC), it is necessary to develop a failure criterion for SOFC PEN structures for the initial failures occurred during cell/stack assembly. In this paper, a global failure criterion is developed for the initial design against mechanical failure of the PEN structure in high temperature SOFCs. The relationship of the critical energy release rate and critical curvature and maximum displacement of the warpage of the cells caused by the temperature differential is established so that the failure reliability of SOFC PEN structures may be determined by the measurement of the curvature and displacement of the warpaged cells.

  2. Contact method to allow benign failure in ceramic capacitor having self-clearing feature

    SciTech Connect (OSTI)

    Myers, John D.; Taylor, Ralph S.

    2012-06-26

    A capacitor exhibiting a benign failure mode has a first electrode layer, a first ceramic dielectric layer deposited on a surface of the first electrode, and a second electrode layer disposed on the ceramic dielectric layer, wherein selected areas of the ceramic dielectric layer have additional dielectric material of sufficient thickness to exhibit a higher dielectric breakdown voltage than the remaining majority of the dielectric layer. The added thickness of the dielectric layer in selected areas allows lead connections to be made at the selected areas of greater dielectric thickness while substantially eliminating a risk of dielectric breakdown and failure at the lead connections, whereby the benign failure mode is preserved.

  3. Failure analysis issues in microelectromechanical systems (MEMS).

    SciTech Connect (OSTI)

    Walraven, Jeremy Allen

    2005-07-01

    Failure analysis and device characterization of MEMS components are critical steps in understanding the root causes of failure and improving device performance. At the wafer and die level these tasks can be performed with little or no sample preparation. Larger challenges occur after fabrication when the device is packaged, capped, sealed, or otherwise obstructed from view. The challenges and issues of MEMS failure analysis lie in identifying the root cause of failure for these packaged, capped, and sealed devices without perturbing the device or its immediate environment. Novel methods of gaining access to the device or preparing the device for analysis are crucial to accurately determining the root cause of failure. This paper will discuss issues identified in performing root cause failure analysis of packaged MEMS devices, as well as the methods employed to analyze them.

  4. A review of macroscopic ductile failure criteria.

    SciTech Connect (OSTI)

    Corona, Edmundo; Reedlunn, Benjamin

    2013-09-01

    The objective of this work was to describe several of the ductile failure criteria com- monly used to solve practical problems. The following failure models were considered: equivalent plastic strain, equivalent plastic strain in tension, maximum shear, Mohr- Coulomb, Wellman's tearing parameter, Johnson-Cook and BCJ MEM. The document presents the main characteristics of each failure model as well as sample failure predic- tions for simple proportional loading stress histories in three dimensions and in plane stress. Plasticity calculations prior to failure were conducted with a simple, linear hardening, J2 plasticity model. The resulting failure envelopes were plotted in prin- cipal stress space and plastic strain space, where the dependence on stress triaxiality and Lode angle are clearly visible. This information may help analysts select a ductile fracture model for a practical problem and help interpret analysis results.

  5. Failure modes in surface micromachined microelectromechanical actuators

    SciTech Connect (OSTI)

    Miller, S.L.; Rodgers, M.S.; LaVigne, G.; Sniegowski, J.J.; Clews, P.; Tanner, D.M.; Peterson, K.A.

    1998-03-01

    In order for the rapidly emerging field of MicroElectroMechanical Systems (MEMS) to meet its extraordinary expectations regarding commercial impact, issues pertaining to how they fail must be understood. The authors identify failure modes common to a broad range of MEMS actuators, including adhesion (stiction) and friction induced failures caused by improper operational methods, mechanical instabilities, and electrical instabilities. Demonstrated methods to mitigate these failure modes include implementing optimized designs, model based operational methods, and chemical surface treatments.

  6. Addressing Failures in Exascale Computing

    SciTech Connect (OSTI)

    Snir, Marc [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Wisniewski, Robert [Intel Corporation] [Intel Corporation; Abraham, Jacob [unknown] [unknown; Adve, Sarita [University of Illinois, Urbana-Champaign] [University of Illinois, Urbana-Champaign; Bagchi, Saurabh [Purdue University] [Purdue University; Balaji, Pavan [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Belak, J. [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Bose, Pradip [IBM T. J. Watson Research Center] [IBM T. J. Watson Research Center; Cappello, Franck [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Carlson, Bill [unknown] [unknown; Chien, Andrew [University of Chicago] [University of Chicago; Coteus, Paul [IBM T. J. Watson Research Center] [IBM T. J. Watson Research Center; DeBardeleben, Nathan [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Diniz, Pedro [University of Southern California] [University of Southern California; Engelmann, Christian [ORNL] [ORNL; Erez, Mattan [University of Texas at Austin] [University of Texas at Austin; Fazzari, Saverio [Booz Allen Hamilton] [Booz Allen Hamilton; Geist, Al [ORNL] [ORNL; Gupta, Rinku [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Johnson, Fred [Science Applications International Corporation (SAIC), Oak Ridge, TN] [Science Applications International Corporation (SAIC), Oak Ridge, TN; Krishnamoorthy, Sriram [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Leyffer, Sven [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Liberty, Dean [AMD] [AMD; Mitra, Subhasish [Stanford University] [Stanford University; Munson, Todd [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Schreiber, Rob [HP Labs] [HP Labs; Stearley, Jon [Sandia National Laboratories (SNL)] [Sandia National Laboratories (SNL); Van Hensbergen, Eric [ARM] [ARM

    2014-01-01

    We present here a report produced by a workshop on Addressing failures in exascale computing' held in Park City, Utah, 4-11 August 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system, discuss existing knowledge on resilience across the various hardware and software layers of an exascale system, and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia, and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  7. Addressing failures in exascale computing

    SciTech Connect (OSTI)

    Snir, Marc; Wisniewski, Robert W.; Abraham, Jacob A.; Adve, Sarita; Bagchi, Saurabh; Balaji, Pavan; Belak, Jim; Bose, Pradip; Cappello, Franck; Carlson, William; Chien, Andrew A.; Coteus, Paul; Debardeleben, Nathan A.; Diniz, Pedro; Engelmann, Christian; Erez, Mattan; Saverio, Fazzari; Geist, Al; Gupta, Rinku; Johnson, Fred; Krishnamoorthy, Sriram; Leyffer, Sven; Liberty, Dean; Mitra, Subhasish; Munson, Todd; Schreiber, Robert; Stearly, Jon; Van Hensbergen, Eric

    2014-05-01

    We present here a report produced by a workshop on “Addressing Failures in Exascale Computing” held in Park City, Utah, August 4–11, 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system; discuss existing knowledge on resilience across the various hardware and software layers of an exascale system; and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia; and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  8. MATERIALS AND MOLECULAR RESEARCH DIVISION. ANNUAL REPORT 1980

    E-Print Network [OSTI]

    Searcy, Alan W.

    2010-01-01

    ductile-brittle transition in impact testing down to liquid helium tempera­ ture. The fracture toughness

  9. Modeling Stress Strain Relationships and Predicting Failure Probabilities For Graphite Core Components

    SciTech Connect (OSTI)

    Duffy, Stephen

    2013-09-09

    This project will implement inelastic constitutive models that will yield the requisite stress-strain information necessary for graphite component design. Accurate knowledge of stress states (both elastic and inelastic) is required to assess how close a nuclear core component is to failure. Strain states are needed to assess deformations in order to ascertain serviceability issues relating to failure, e.g., whether too much shrinkage has taken place for the core to function properly. Failure probabilities, as opposed to safety factors, are required in order to capture the bariability in failure strength in tensile regimes. The current stress state is used to predict the probability of failure. Stochastic failure models will be developed that can accommodate possible material anisotropy. This work will also model material damage (i.e., degradation of mechanical properties) due to radiation exposure. The team will design tools for components fabricated from nuclear graphite. These tools must readily interact with finite element software--in particular, COMSOL, the software algorithm currently being utilized by the Idaho National Laboratory. For the eleastic response of graphite, the team will adopt anisotropic stress-strain relationships available in COMSO. Data from the literature will be utilized to characterize the appropriate elastic material constants.

  10. Opportunistically Reconstructing a Network's Failure History /

    E-Print Network [OSTI]

    Turner, Daniel Joseph

    2013-01-01

    to identify anomalies in datacenter applications [40]. Theytraffic data from a datacenter network [14]. They use thesethe failures in a datacenter environment. The techniques

  11. STUDY OF THE RHIC BPM SMA CONNECTOR FAILURE PROBLEM

    SciTech Connect (OSTI)

    LIAW,C.; SIKORA, R.; SCHROEDER, R.

    2007-06-25

    About 730 BPMs are mounted on the RHIC CQS and Triplet super-conducting magnets. Semi-rigid coaxial cables are used to bring the electrical signal from the BPM feedthroughs to the outside flanges. at the ambient temperature. Every year around 10 cables will lose their signals during the operation. The connection usually failed at the warm end of the cable. The problems were either the solder joint failed or the center conductor retracted out of the SMA connector. Finite element analyses were performed to understand the failure mechanism of the solder joint. The results showed that (1) The SMA center conductor can separate from the mating connector due to the thermal retraction. (2) The maximum thermal stress at the warm end solder joint can exceed the material strength of the Pb37/Sn63 solder material and (3) The magnet ramping frequency (-10 Hz), during the machine startup, can possibly resonant the coaxial cable and damage the solder joints, especially when a fracture is initiated. Test results confirmed that by using the silver bearing solder material (a higher strength material) and by crimping the cable at the locations close to the SMA connector (to prevent the center conductor from retracting) can effectively resolve the connector failure problem.

  12. Criticality in the approach to failure in amorphous solids

    E-Print Network [OSTI]

    Jie Lin; Thomas Gueudré; Alberto Rosso; Matthieu Wyart

    2015-07-28

    Failure of amorphous solids is fundamental to various phenomena, including landslides and earthquakes. Recent experiments indicate that highly plastic regions form elongated structures that are especially apparent near the maximal shear stress $\\Sigma_{\\max}$ where failure occurs. This observation suggested that $\\Sigma_{\\max}$ acts as a critical point where the length scale of those structures diverges, possibly causing macroscopic transient shear bands. Here we argue instead that the entire solid phase ($\\Sigmaplasticity always involves system-spanning events, and that their magnitude diverges at $\\Sigma_{\\max}$ independently of the presence of shear bands. We relate the statistics and fractal properties of these rearrangements to an exponent $\\theta$ that captures the stability of the material, which is observed to vary continuously with stress, and we confirm our predictions in elastoplastic models.

  13. Summary of failure analysis activities at Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Cowgill, M.G.; Czajkowski, C.J.; Franz, E.M.

    1996-10-01

    Brookhaven National Laboratory has for many years conducted examinations related to the failures of nuclear materials and components. These examinations included the confirmation of root cause analyses, the determination of the causes of failure, identification of the species that accelerate corrosion, and comparison of the results of nondestructive examinations with those obtained by destructive examination. The results of those examinations, which had previously appeared in various formats (formal and informal reports, journal articles, etc.), have been collected together and summarized in the present report. The report is divided into sections according to the general subject matter (for example, corrosion, fatigue, etc.). Each section presents summaries of the information contained in specific reports and publications, all of which are fully identified as to title, authors, report number or journal reference, date of publication, and FIN number under which the work was performed.

  14. An assessment of the state of the art in predicting the failure of ceramics: Final report

    SciTech Connect (OSTI)

    Boulet, J.A.M.

    1988-03-01

    The greatest weakness in existing design strategies for brittle fracture is in the narrow range of conditions for which the strategies are adequate. The primary reason for this weakness is the use of simplistic mechanical models of fracture processes and unverified statistical models of materials. To improve the design methodology, the models must first be improved. Specifically recommended research goals are: to develop models of cracks with realistic geometry under arbitrary stress states; to identify and model the most important relationships between fracture processes and microstructural features; to assess the technology available for acquiring statistical data on microstructure and flaw populations, and to establish the amount of data required for verification of statistical models; and to establish a computer-based fracture simulation that can incorporate a wide variety of mechanical and statistical models and crack geometries, as well as arbitrary stress states. 204 refs., 2 tabs.

  15. Optimal Software Rejuvenation for Tolerating Soft Failures

    E-Print Network [OSTI]

    Telek, Miklós

    Optimal Software Rejuvenation for Tolerating Soft Failures Andr'as Pfening a;1 , Sachin Garg b;2 of software ``aging'' has come to light which causes performance of a software to degrade with time. Software of determining the optimal time to rejuvenate a server type software which experiences ``soft failures

  16. Received 14 Nov 2013 | Accepted 20 Dec 2013 | Published 28 Jan 2014 Overcoming the brittleness of glass through

    E-Print Network [OSTI]

    Barthelat, Francois

    assembly16. These new materials demonstrate that bio-inspired strategies can be harnessed to achieve both displayed by some of these new bio- inspired materials, the level of `toughness' amplification observed. Barthelat1 Highly mineralized natural materials such as teeth or mollusk shells boast unusual combi- nations

  17. Low-rise shear wall failure modes

    SciTech Connect (OSTI)

    Farrar, C.R. (Los Alamos National Lab., NM (USA)); Hashimoto, P.S. (EQE Engineering, Inc., Costa Mesa, CA (USA)); Reed, J.W. (Benjamin (J.R.) and Associates, Inc., Mountain View, CA (USA))

    1991-01-01

    A summary of the data that are available concerning the structural response of low-rise shear walls is presented. This data will be used to address two failure modes associated with the shear wall structures. First, data concerning the seismic capacity of the shear walls with emphasis on excessive deformations that can cause equipment failure are examined. Second, data concerning the dynamic properties of shear walls (stiffness and damping) that are necessary to compute the seismic inputs to attached equipment are summarized. This case addresses the failure of equipment when the structure remains functional. 23 refs.

  18. Valve system incorporating single failure protection logic

    DOE Patents [OSTI]

    Ryan, Rodger (San Jose, CA); Timmerman, Walter J. H. (Saratoga, CA)

    1980-01-01

    A valve system incorporating single failure protective logic. The system consists of a valve combination or composite valve which allows actuation or de-actuation of a device such as a hydraulic cylinder or other mechanism, integral with or separate from the valve assembly, by means of three independent input signals combined in a function commonly known as two-out-of-three logic. Using the input signals as independent and redundant actuation/de-actuation signals, a single signal failure, or failure of the corresponding valve or valve set, will neither prevent the desired action, nor cause the undesired action of the mechanism.

  19. Geothermal Literature Review At Long Valley Caldera Geothermal...

    Open Energy Info (EERE)

    distinguish between earthquake sequences that result from relaxation of existing stress accumulation through brittle failure and those in which brittle failure is driven by...

  20. Improving service availability during link failure transients through alternate routing 

    E-Print Network [OSTI]

    Vellanki, Siridhar

    2003-01-01

    A link failure in a network results in interruption of service for many end users. Currently, routers observing a link failure, recompute their routing tables to find new routes around the failure. However, the network ...

  1. Universitat Augsburg Failure-Sensitive Specification

    E-Print Network [OSTI]

    Reif, Wolfgang

    techniques like fault tree analysis (FTA) [14], failure modes and effects analysis (FMEA), or preliminary as well. In this context we already formalized techniques like FTA [12][4] or FMEA. This paper presents

  2. Impact of Motor Failures on Payback Periods 

    E-Print Network [OSTI]

    Cheek, K. F.; Pillay, P.; Dudley, K. J.

    1995-01-01

    This paper uses MotorMaster and Vaughen's Complete Price Guide to determine payback periods for different motor failure scenarios. Some scenarios considered are rewinds, reconditions, and replacement of bearings. Prices for these repairs...

  3. Metallurgical failures in fossil fired boilers

    SciTech Connect (OSTI)

    French, D.N.

    1993-01-01

    This book provides a comprehensive catalog of the types of metallurgical failures common to boilers. The author uses actual case histories of boiler shutdowns, and documents the full range of causes of boiler tube failure. A blueprint is provided for cutting maintenance costs and upgrading the efficiency and reliability of any power plant operation. Individual chapters are processed separately for inclusion in the appropriate data bases.

  4. Metallurgical failure analysis of a propane tank boiling liquid...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Metallurgical failure analysis of a propane tank boiling liquid expanding vapor explosion (BLEVE). Citation Details In-Document Search Title: Metallurgical failure...

  5. Failure Stress and Apparent Elastic Modulus of Diesel Particulate...

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

    Failure Stress and Apparent Elastic Modulus of Diesel Particulate Filter Ceramics Failure Stress and Apparent Elastic Modulus of Diesel Particulate Filter Ceramics Three...

  6. Integrating Electricity Subsector Failure Scenarios into a Risk...

    Energy Savers [EERE]

    Integrating Electricity Subsector Failure Scenarios into a Risk Assessment Methodology (December 2013) Integrating Electricity Subsector Failure Scenarios into a Risk Assessment...

  7. EARTH SURFACE PROCESSES AND LANDFORMS, VOL. 20, 243-EFFECTS OF SOIL MOISTURE DYNAMICS ON SLOPE FAILURE

    E-Print Network [OSTI]

    McDonnell, Jeffrey J.

    24 November 1993 ABSTRACT Field observations of shoreline conditions at Hyrum Reservoir , Uw 11 for a multiple-layered bluff en' ironment of sand and clay layers. Failure is initiated by wetting and drying of clay sediments, which produces horizontal cr;' cks within bluff material. These cracks appear to pene

  8. FAILURE OF ZIRCALOY-4 SHEET CONTAINING HYDRIDE BLISTERS O.N. Pierron1

    E-Print Network [OSTI]

    Motta, Arthur T.

    FAILURE OF ZIRCALOY-4 SHEET CONTAINING HYDRIDE BLISTERS O.N. Pierron1 , D.A. Koss1 , A.T. Motta2 , R.S. Daum3 , and K.S. Chan4 1 Dept. Materials Science and Engineering, Penn State Univ., University Park, PA 16802 2 Dept. Mechanical and Nuclear Engineering, Penn State University, University Park, PA

  9. Failure mechanisms of polyimide and perfluoroalkoxy films under high frequency pulses

    E-Print Network [OSTI]

    Southampton, University of

    Failure mechanisms of polyimide and perfluoroalkoxy films under high frequency pulses Weijun Yin1 of polyimide and perfluoroalkoxy high temperature films under unipolar and bipolar repetitive pulses of art high temperature insulation materials, such as polyimide (PI), and perfluoroalkoxy (PFA) films

  10. On modeling damage and failure in ceramic matrix fiber reinforced composites Anthony M. Waas

    E-Print Network [OSTI]

    Mease, Kenneth D.

    On modeling damage and failure in ceramic matrix fiber reinforced composites Anthony M. Waas Seattle, WA 98195-2400 Fiber reinforced ceramic matrix composites (CMC) are targeted for many jet engine of the matrix material. Multiple analytical ply-level models have been developed to predict crack spacing

  11. An Experimental Study of Shear-Dominated Failure in the 2013 Sandia Fracture Challenge Specimen

    SciTech Connect (OSTI)

    Corona, Edmundo; Deibler, Lisa Anne; Reedlunn, Benjamin; Ingraham, Mathew Duffy; Williams, Shelley

    2015-04-01

    This report presents an experimental study motivated by results obtained during the 2013 Sandia Fracture Challenge. The challenge involved A286 steel, shear-dominated compression specimens whose load-deflection response contained a load maximum fol- lowed by significant displacement under decreasing load, ending with a catastrophic fracture. Blind numerical simulations deviated from the experiments well before the maximum load and did not predict the failure displacement. A series of new tests were conducted on specimens machined from the original A286 steel stock to learn more about the deformation and failure processes in the specimen and potentially improve future numerical simulations. The study consisted of several uniaxial tension tests to explore anisotropy in the material, and a set of new tests on the compression speci- men. In some compression specimen tests, stereo digital image correlation (DIC) was used to measure the surface strain fields local to the region of interest. In others, the compression specimen was loaded to a given displacement prior to failure, unloaded, sectioned, and imaged under the microscope to determine when material damage first appeared and how it spread. The experiments brought the following observations to light. The tensile tests revealed that the plastic response of the material is anisotropic. DIC during the shear- dominated compression tests showed that all three in-plane surface strain components had maxima in the order of 50% at the maximum load. Sectioning of the specimens revealed no signs of material damage at the point where simulations deviated from the experiments. Cracks and other damage did start to form approximately when the max- imum load was reached, and they grew as the load decreased, eventually culminating in catastrophic failure of the specimens. In addition to the steel specimens, a similar study was carried out for aluminum 7075-T651 specimens. These specimens achieved much lower loads and displacements, and failure occurred very close to the maximum in the load-deflection response. No material damage was observed in these specimens, even when failure was imminent. In the future, we plan to use these experimental results to improve numerical simu- lations of the A286 steel experiments, and to improve plasticity and failure models for the Al 7075 stock. The ultimate goal of our efforts is to increase our confidence in the results of numerical simulations of elastic-plastic structural behavior and failure.

  12. Material Misfits

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

    Issues submit Material Misfits How well nanocomposite materials align at their interfaces determines what properties they have, opening broad new avenues of materials-science...

  13. Mining Simulation Metrics for Failure Triage in Regression Testing

    E-Print Network [OSTI]

    Veneris, Andreas

    are grouped by applying data-mining clustering algorithms. Fi- nally, the generated failure clustersMining Simulation Metrics for Failure Triage in Regression Testing Zissis Poulos1 , Andreas Veneris of failures can be exposed. These failures need to be properly grouped and distributed among engineers

  14. UTILITIES PROBLEMS AND FAILURES Electrical or plumbing failure/Flooding/Water leak/Natural gas

    E-Print Network [OSTI]

    Fernandez, Eduardo

    UTILITIES PROBLEMS AND FAILURES Electrical or plumbing failure/Flooding/Water leak/Natural gas for electrical shock. NOTIFY University Police. What should I do if I smell natural or propane gas? LEAVE/Repair line, 7-6333, or CALL the Campus University Police or Security at (561) 297-3500 or 911

  15. UTILITIES PROBLEMS AND FAILURES ELECTRICAL OR PLUMBING FAILURE/FLOODING/WATER LEAK

    E-Print Network [OSTI]

    Fernandez, Eduardo

    UTILITIES PROBLEMS AND FAILURES ELECTRICAL OR PLUMBING FAILURE/FLOODING/WATER LEAK NATURAL GAS - F 8a - 5p HBOI@FAU Security (772) 216-1124 Afterhours, Weekends or Holidays What should I do Police 911. · NOTIFY Building Safety personnel when possible. What should I do if I smell natural

  16. UTILITIES PROBLEMS AND FAILURES Electrical or plumbing failure/Flooding/Water leak/Natural gas or

    E-Print Network [OSTI]

    Fernandez, Eduardo

    UTILITIES PROBLEMS AND FAILURES Electrical or plumbing failure/Flooding/Water leak/Natural gas Physical Plant (772) 242-2246 M - F 8a - 5p (954) 762-5040 HBOI@FAU Security (772) 216-1124 Afterhours University Police. NOTIFY Building Safety personnel when possible. What should I do if I smell natural

  17. Embrittlement and Flow Localization in Reactor Structural Materials

    SciTech Connect (OSTI)

    Xianglin Wu; Xiao Pan; James Stubbins

    2006-10-06

    Many reactor components and structural members are made from metal alloys due, in large part, to their strength and ability to resist brittle fracture by plastic deformation. However, brittle fracture can occur when structural material cannot undergo extensive, or even limited, plastic deformation due to irradiation exposure. Certain irradiation conditions lead to the development of a damage microstructure where plastic flow is limited to very small volumes or regions of material, as opposed to the general plastic flow in unexposed materials. This process is referred to as flow localization or plastic instability. The true stress at the onset of necking is a constant regardless of the irradiation level. It is called 'critical stress' and this critical stress has strong temperature dependence. Interrupted tensile testes of 316L SS have been performed to investigate the microstructure evolution and competing mechanism between mechanic twinning and planar slip which are believed to be the controlling mechanism for flow localization. Deformation twinning is the major contribution of strain hardening and good ductility for low temperatures, and the activation of twinning system is determined by the critical twinning stress. Phases transform and texture analyses are also discussed in this study. Finite element analysis is carried out to complement the microstructural analysis and for the prediction of materaials performance with and without stress concentration and irradiation.

  18. Can complexity decrease in Congestive Heart failure?

    E-Print Network [OSTI]

    Mukherjee, Sayan; Banerjee, Santo; Ariffin, M R K; Rondoni, Lamberto; Bhattacharya, D K

    2015-01-01

    The complexity of a signal can be measured by the Recurrence period density entropy (RPDE) from the reconstructed phase space. We have chosen a window based RPDE method for the classification of signals, as RPDE is an average entropic measure of the whole phase space. We have observed the changes in the complexity in cardiac signals of normal healthy person (NHP) and congestive heart failure patients (CHFP). The results show that the cardiac dynamics of a healthy subject is more complex and random compare to the same for a heart failure patient, whose dynamics is more deterministic. We have constructed a general threshold to distinguish the border line between a healthy and a congestive heart failure dynamics. The results may be useful for wide range for physiological and biomedical analysis.

  19. Can complexity decrease in Congestive Heart failure?

    E-Print Network [OSTI]

    Sayan Mukherjee; Sanjay Kumar Palit; Santo Banerjee; M. R. K. Ariffin; Lamberto Rondoni; D. K. Bhattacharya

    2015-08-06

    The complexity of a signal can be measured by the Recurrence period density entropy (RPDE) from the reconstructed phase space. We have chosen a window based RPDE method for the classification of signals, as RPDE is an average entropic measure of the whole phase space. We have observed the changes in the complexity in cardiac signals of normal healthy person (NHP) and congestive heart failure patients (CHFP). The results show that the cardiac dynamics of a healthy subject is more complex and random compare to the same for a heart failure patient, whose dynamics is more deterministic. We have constructed a general threshold to distinguish the border line between a healthy and a congestive heart failure dynamics. The results may be useful for wide range for physiological and biomedical analysis.

  20. Generic failure mechanisms in adhesive bonds

    E-Print Network [OSTI]

    Hass, Philipp; Niemz, Peter

    2015-01-01

    The failure of adhesive bondlines has been studied at the microscopic level via tensile tests. Stable crack propagation could be generated by means of samples with improved geometry, which made in-situ observations possible. The interaction of cracks with adhesive bondlines under various angles to the crack propagation was the focus of this study as well as the respective loading situations for the adhesives UF, PUR, and PVAc, which have distinctly different mechanical behaviors. It is shown how adhesive properties influence the occurrence of certain failure mechanisms and determine their appearance and order of magnitude. With the observed failure mechanisms, it becomes possible to predict the propagation path of a crack through the specimen.

  1. Reassessment of the BWR scram failure probability

    SciTech Connect (OSTI)

    Burns, E.T.

    1989-01-01

    As part of the Severe Accident Policy Statement implementation, the probabilistic quantification of accident sequence frequencies that may lead to core damage is a key element in demonstrating a plant's safety status relative to US Nuclear Regulatory Commission (NRC) staff goals. One of the key quantitative inputs in a boiling water reactor (BWR) probabilistic risk assessment is the probability of a failure to scram. The assessment of this failure probability has been the subject of a long and continuing debate over the adequacy of available data and analytic modeling. This report provides a summary of the status of this debate, including the latest data, and provides a revision to the characterization of the failure probability originally published in NUREG 0460 and the Utility Group on Anticipated Transient Without Scram (ATWS) Petition.

  2. Modeling and Automatic Failure Analysis of Safety-Critical Systems Using Extended Safecharts

    E-Print Network [OSTI]

    Hsiung, Pao-Ann

    techniques, such as fault tree analysis (FTA), failure modes and effects analysis (FMEA), failure modes

  3. Materials of Gasification

    SciTech Connect (OSTI)

    2005-09-15

    The objective of this project was to accumulate and establish a database of construction materials, coatings, refractory liners, and transitional materials that are appropriate for the hardware and scale-up facilities for atmospheric biomass and coal gasification processes. Cost, fabricability, survivability, contamination, modes of corrosion, failure modes, operational temperatures, strength, and compatibility are all areas of materials science for which relevant data would be appropriate. The goal will be an established expertise of materials for the fossil energy area within WRI. This would be an effort to narrow down the overwhelming array of materials information sources to the relevant set which provides current and accurate data for materials selection for fossil fuels processing plant. A significant amount of reference material on materials has been located, examined and compiled. The report that describes these resources is well under way. The reference material is in many forms including texts, periodicals, websites, software and expert systems. The most important part of the labor is to refine the vast array of available resources to information appropriate in content, size and reliability for the tasks conducted by WRI and its clients within the energy field. A significant has been made to collate and capture the best and most up to date references. The resources of the University of Wyoming have been used extensively as a local and assessable location of information. As such, the distribution of materials within the UW library has been added as a portion of the growing document. Literature from recent journals has been combed for all pertinent references to high temperature energy based applications. Several software packages have been examined for relevance and usefulness towards applications in coal gasification and coal fired plant. Collation of the many located resources has been ongoing. Some web-based resources have been examined.

  4. Yield criteria for quasibrittle and frictional materials

    E-Print Network [OSTI]

    Davide Bigoni; Andrea Piccolroaz

    2010-10-09

    A new yield/damage function is proposed for modelling the inelastic behaviour of a broad class of pressure-sensitive, frictional, ductile and brittle-cohesive materials. The yield function allows the possibility of describing a transition between the shape of a yield surface typical of a class of materials to that typical of another class of materals. This is a fundamental key to model the behaviour of materials which become cohesive during hardening (so that the shape of the yield surface evolves from that typical of a granular material to that typical of a dense material), or which decrease cohesion due to damage accumulation. The proposed yield function is shown to agree with a variety of experimental data relative to soil, concrete, rock, metallic and composite powders, metallic foams, porous metals, and polymers. The yield function represents a single, convex and smooth surface in stress space approaching as limit situations well-known criteria and the extreme limits of convexity in the deviatoric plane. The yield function is therefore a generalization of several criteria, including von Mises, Drucker-Prager, Tresca, modified Tresca, Coulomb-Mohr, modified Cam-clay, and --concerning the deviatoric section-- Rankine and Ottosen. Convexity of the function is proved by developing two general propositions relating convexity of the yield surface to convexity of the corresponding function. These propositions are general and therefore may be employed to generate other convex yield functions.

  5. Multiscale modeling of the brittle to ductile transition S.J. Noronha, J. Huang, N.M. Ghoniem *

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    zone is represented as an array of discrete dislocations emitted from crack-tip sources. In their model they equated the competing forces acting on a dislocation near the crack-tip, and derived material parameters, the surface en- ergy (c) and the unstable stacking fault energy (cus) [2

  6. Survey on Failure Modes and Failure Mechanisms in Digital Components and Systems

    SciTech Connect (OSTI)

    Cetiner, Mustafa Sacit; Korsah, Kofi; Muhlheim, Michael David

    2009-01-01

    This paper presents the preliminary results of a survey on the operating experience of a broad range of digital components and systems deployed in various industries. The primary objective of this survey is to identify principal modes and mechanisms of failure in field-deployed digital systems. Earlier works have sought to determine the failure rates of various classes of digital devices with the intent to integrate this information into the risk analysis calculations though still immature for such systems. Failure rates of individual components or systems are not taken into account in this evaluation; only failure modes and their respective probabilistic distribution are considered. Preliminary results from two data sources, SPIDR and FARADIP, are presented.

  7. VOLUME 80, NUMBER 4 P H Y S I C A L R E V I E W L E T T E R S 26 JANUARY 1998 Ideal Brittle Fracture of Silicon Studied with Molecular Dynamics

    E-Print Network [OSTI]

    Texas at Austin. University of

    Fracture of Silicon Studied with Molecular Dynamics Dominic Holland and M. Marder Center for Nonlinear September 1997) Dynamic fracture experiments measure crack velocity versus energy flux to the tip. We report, no determination whether ideal brittle fracture is a pathological feature of an artificial model, or whether

  8. The unifying role of dissipative action in the dynamic failure of solids

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

    Grady, Dennis

    2015-05-19

    Dissipative action, the product of dissipation energy and transport time, is fundamental to the dynamic failure of solids. Invariance of the dissipative action underlies the fourth-power nature of structured shock waves observed in selected solid metals and compounds. Dynamic failure through shock compaction, tensile spall and adiabatic shear are also governed by a constancy of the dissipative action. This commonality underlying the various modes of dynamic failure is described and leads to deeper insights into failure of solids in the intense shock wave event. These insights are in turn leading to a better understanding of the shock deformation processes underlyingmore »the fourth-power law. Experimental result and material models encompassing the dynamic failure of solids are explored for the purpose of demonstrating commonalities leading to invariance of the dissipation action. As a result, calculations are extended to aluminum and uranium metals with the intent of predicting micro-scale energetics and spatial scales in the structured shock wave.« less

  9. Predicting age of ovarian failure after radiation to a field that includes the ovaries

    SciTech Connect (OSTI)

    Wallace, W. Hamish B. . E-mail: Hamish.Wallace@ed.ac.uk; Thomson, Angela B.; Saran, Frank; Kelsey, Tom W.

    2005-07-01

    Purpose: To predict the age at which ovarian failure is likely to develop after radiation to a field that includes the ovary in women treated for cancer. Methods and Materials: Modern computed tomography radiotherapy planning allows determination of the effective dose of radiation received by the ovaries. Together with our recent assessment of the radiosensitivity of the human oocyte, the effective surviving fraction of primordial oocytes can be determined and the age of ovarian failure, with 95% confidence limits, predicted for any given dose of radiotherapy. Results: The effective sterilizing dose (ESD: dose of fractionated radiotherapy [Gy] at which premature ovarian failure occurs immediately after treatment in 97.5% of patients) decreases with increasing age at treatment. ESD at birth is 20.3 Gy; at 10 years 18.4 Gy, at 20 years 16.5 Gy, and at 30 years 14.3 Gy. We have calculated 95% confidence limits for age at premature ovarian failure for estimated radiation doses to the ovary from 1 Gy to the ESD from birth to 50 years. Conclusions: We report the first model to reliably predict the age of ovarian failure after treatment with a known dose of radiotherapy. Clinical application of this model will enable physicians to counsel women on their reproductive potential following successful treatment.

  10. Covetic Materials

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

    Can re-melt, dilute, alloy... Fabrication of Covetic Materials - Nanocarbon Infusion 3 4 Technical Approach Unusual Characteristics of Covetic Materials ("covalent" &...

  11. Failure of silicon nitride under uniaxial compression at high temperature

    E-Print Network [OSTI]

    Gei, Massimiliano

    nitride cylinders have been investigated under uniaxial compression at 1200 °C in air. Samples has been carried out in order to de- scribe the onset of the specific failure mode. The first failure

  12. Gearbox Typical Failure Modes, Detection, and Mitigation Methods (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.

    2014-01-01

    This presentation was given at the AWEA Operations & Maintenance and Safety Seminar and focused on what the typical gearbox failure modes are, how to detect them using detection techniques, and strategies that help mitigate these failures.

  13. Users May Now Clear Their Own Login Failures

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

    Users May Now Clear Their Own Login Failures Users May Now Clear Their Own Login Failures May 16, 2013 by Francesca Verdier (0 Comments) Users may now clear their own login...

  14. Quality of Service of Crash-Recovery Failure Detectors 

    E-Print Network [OSTI]

    Ma, Tiejun

    2007-11-07

    This thesis presents the results of an investigation into the failure detection problem. We consider the specific case of the Quality of Service (QoS) of crash failure detection. In contrast to previous work, we address ...

  15. Timing analysis of PWR fuel pin failures

    SciTech Connect (OSTI)

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Straka, M. (Halliburton NUS, Idaho Falls, ID (United States))

    1992-09-01

    This report discusses research conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PF1/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design burnup. Using peaking factors commensurate with actual burnups would result in longer intervals for both reactor designs. This document provides appendices K and L of this report which provide plots for the timing analysis of PWR fuel pin failures for Oconee and Seabrook respectively.

  16. 2008 Midwest Levee Failure: Erosion Studies 

    E-Print Network [OSTI]

    Bernhardt, Michelle Lee

    2011-02-22

    of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Jean-Louis Briaud Committee Members, Giovanna Biscontin Russell W. Jessup Head of Department, Mark Burris December 2009 Major Subject: Civil Engineering iii... ABSTRACT 2008 Midwest Levee Failures: Erosion Studies. (December 2009) Michelle Lee Bernhardt, B.S., Texas A&M University Chair of Advisory Committee: Dr. Jean-Louis Briaud The United States contains an estimated 100,000 miles (160000 km...

  17. Export Failure and its Consequences: Theory and Evidence

    E-Print Network [OSTI]

    Mora, Jesse

    2015-01-01

    for export success . . . . . . . . . . . . . . . VA Model with Export Failure, Marketing Costs, and Financial2 Export Expansions of Products and Destinations I

  18. Estimating Failure Propagation in Models of Cascading Blackouts

    SciTech Connect (OSTI)

    Dobson, Ian [University of Wisconsin, Madison; Carreras, Benjamin A [ORNL; Lynch, Vickie E [ORNL; Nkei, Bertrand [ORNL; Newman, David E [University of Alaska

    2005-09-01

    We compare and test statistical estimates of failure propagation in data from versions of a probabilistic model of loading-dependent cascading failure and a power systems blackout model of cascading transmission line overloads. The comparisons suggest mechanisms affecting failure propagation and are an initial step towards monitoring failure propagation from practical system data. Approximations to the probabilistic model describe the forms of probability distributions of cascade sizes.

  19. Soft Failures in Large Datacenters Sriram Sankar and Sudhanva Gurumurthi

    E-Print Network [OSTI]

    Gurumurthi, Sudhanva

    Soft Failures in Large Datacenters Sriram Sankar and Sudhanva Gurumurthi Abstract-- A major problem in managing large-scale datacenters is diagnosing and fixing machine failures. Most large datacenter an important issue at large datacenters with minimum human intervention. Soft failures in the datacenter do

  20. A statistically predictive model for future monsoon failure in India

    E-Print Network [OSTI]

    Levermann, Anders

    A statistically predictive model for future monsoon failure in India Jacob Schewe1,2 and Anders Information #12;A statistically predictive model for future monsoon failure in India 2 mm/day numberofyears 0 statistically predictive model for future monsoon failure in India 4 30 o S 15o S 0 o 15o N 30o N A dry May B

  1. Failure Time Analysis for LMS Algorithms Adel A. Zerai

    E-Print Network [OSTI]

    Bucklew, James Antonio

    Failure Time Analysis for LMS Algorithms Adel A. Zerai Electronics Engineering Technology) analysis of the LMS adaptive algorithms (#12;lters). Such analysis is extremely important when failure of time (a clump of large errors). We use Poisson approximation to study excursions (failure) of the LMS

  2. NO. ~EV. NO. Failure Modes and Effects Analysis -LRRR

    E-Print Network [OSTI]

    Rathbun, Julie A.

    of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in the LRRR experiment for the critical failure areas. A TM 868 contains the results of a final FMEA for the LRRR experiment. 2. 0 SUMMARY Since an LRRR was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA

  3. Failure Modes and Effects Analysis 300 Array -LRRR

    E-Print Network [OSTI]

    Rathbun, Julie A.

    of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in a system and to remove failure areas. 1. 2 This memo contains the results of the final FMEA for the 300 Array LRRR experiment was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA will not dwell in the aspects

  4. BWR containment failure analysis during degraded-core accidents

    SciTech Connect (OSTI)

    Yue, D.D.

    1982-06-06

    This paper presents a containment failure mode analysis during a spectrum of postulated degraded core accident sequences in a typical 1000-MW(e) boiling water reactor (BWR) with a Mark-I wetwell containment. Overtemperature failure of containment electric penetration assemblies (CEPAs) has been found to be the major failure mode during such accidents.

  5. Probabilistic Failure Detection for Efficient Distributed Storage Maintenance* , Zhi Yang*

    E-Print Network [OSTI]

    Almeroth, Kevin C.

    avail- ability. Node failures can be transient or permanent. While the system must generate new replicasProbabilistic Failure Detection for Efficient Distributed Storage Maintenance* Jing Tian* , Zhi@cs.ucsb.edu Abstract Distributed storage systems often use data replica- tion to mask failures and guarantee high data

  6. Modeling Stochastic Correlated Failures and their Effects on Network Reliability

    E-Print Network [OSTI]

    Hayat, Majeed M.

    in this field have used this concept to generate geographically correlated failures (e.g. [1] and [2]). SomeModeling Stochastic Correlated Failures and their Effects on Network Reliability Mahshid Rahnamay--The physical infrastructure of communication net- works is vulnerable to spatially correlated failures arising

  7. Algorithm-Based Fault Tolerance for Fail-Stop Failures

    E-Print Network [OSTI]

    Dongarra, Jack

    after failures, the next generation high performance computing applications need to be able to continue1 Algorithm-Based Fault Tolerance for Fail-Stop Failures Zizhong Chen and Jack Dongarra Abstract Fail-stop failures in distributed environments are often tolerated by checkpointing or message logging

  8. PDC IC WELD FAILURE EVALUATION AND RESOLUTION

    SciTech Connect (OSTI)

    Korinko, P.; Howard, S.; Maxwell, D.; Fiscus, J.

    2012-04-16

    During final preparations for start of the PDCF Inner Can (IC) qualification effort, welding was performed on an automated weld system known as the PICN. During the initial weld, using a pedigree canister and plug, a weld defect was observed. The defect resulted in a hole in the sidewall of the canister, and it was observed that the plug sidewall had not been consumed. This was a new type of failure not seen during development and production of legacy Bagless Transfer Cans (FB-Line/Hanford). Therefore, a team was assembled to determine the root cause and to determine if the process could be improved. After several brain storming sessions (MS and T, R and D Engineering, PDC Project), an evaluation matrix was established to direct this effort. The matrix identified numerous activities that could be taken and then prioritized those activities. This effort was limited by both time and resources (the number of canisters and plugs available for testing was limited). A discovery process was initiated to evaluate the Vendor's IC fabrication process relative to legacy processes. There were no significant findings, however, some information regarding forging/anneal processes could not be obtained. Evaluations were conducted to compare mechanical properties of the PDC canisters relative to the legacy canisters. Some differences were identified, but mechanical properties were determined to be consistent with legacy materials. A number of process changes were also evaluated. A heat treatment procedure was established that could reduce the magnetic characteristics to levels similar to the legacy materials. An in-situ arc annealing process was developed that resulted in improved weld characteristics for test articles. Also several tack welds configurations were addressed, it was found that increasing the number of tack welds (and changing the sequence) resulted in decreased can to plug gaps and a more stable weld for test articles. Incorporating all of the process improvements for the actual can welding process, however, did not result in an improved weld geometry. Several possibilities for the lack of positive response exist, some of which are that (1) an insufficient number of test articles were welded under prototypic conditions, (2) the process was not optimized so that significant improvements were observable over the 'noise', and (3) the in-situ arc anneal closed the gap down too much so the can was unable to exhaust pressure ahead of the weld. Several operational and mechanical improvements were identified. The weld clamps were changed to a design consistent with those used in the legacy operations. A helium puff operation was eliminated; it is believed that this operation was the cause of the original weld defect. Also, timing of plug mast movement was found to correspond with weld irregularities. The timing of the movement was changed to occur during weld head travel between tacks. In the end a three sequential tack weld process followed by a pulse weld at the same current and travel speed as was used for the legacy processes was suggested for use during the IC qualification effort. Relative to legacy welds, the PDC IC weld demonstrates greater fluctuation in the region of the weld located between tack welds. However, canister weld response (canister to canister) is consistent and with the aid of the optical mapping system (for targeting the cut position) is considered adequate. DR measurements and METs show the PDC IC welds to have sufficient ligament length to ensure adequate canister pressure/impact capacity and to ensure adequate stub function. The PDC welding process has not been optimized as a result of this effort. Differences remain between the legacy BTC welds and the PDC IC weld, but these differences are not sufficient to prevent resumption of the current PDC IC qualification effort. During the PDC IC qualification effort, a total of 17 cans will be welded and a variety of tests/inspections will be performed. The extensive data collected during that qualification effort should be of a sufficient population to determ

  9. Tube fragmentation of multiple materials.

    SciTech Connect (OSTI)

    Thornhill, Tom Finley, III (Ktech Corporation, Albuquerque, NM); Vogler, Tracy John; Chhabildas, Lalit Chandra

    2003-07-01

    In the current study we are developing an experimental fracture material property test method specific to dynamic fragmentation. This test method allows the study of fracture fragmentation in a reproducible laboratory environment under well-controlled loading conditions. Motion and fragmentation of the specimen are diagnosed using framing camera, VISAR and soft recovery methods. Fragmentation properties of several steels, nitinol, tungsten alloy, copper, aluminum, and titanium have been obtained to date. The values for fragmentation toughness, and failure threshold will be reported, as well as effects in these values as the material strain-rate is varied through changes in wall thickness and impact conditions.

  10. Tube Fragmentation of Multiple Materials

    SciTech Connect (OSTI)

    Thornhill, T. F. [Ktech Corporation, Suite 400, 2201 Buena Vista SE, Albuquerque, NM 87106-4265 (United States); Chhabildas, L. C.; Vogler, T. J. [Sandia National Laboratories, Department 1647, PO Box 5800, Albuquerque, NM 87185 (United States)

    2006-07-28

    In the current study we are developing an experimental fracture material property test method specific to dynamic fragmentation. This test method allows the study of fracture fragmentation in a reproducible laboratory environment under well-controlled loading conditions. Motion and fragmentation of the specimen are diagnosed using framing camera, VISAR and soft recovery methods. Fragmentation properties of several steels, nitinol, tungsten alloy, copper, aluminum, and titanium have been obtained to date. The values for fragmentation toughness, and failure threshold will be reported, as well as effects in these values as the material strain-rate is varied through changes in wall thickness and impact conditions.

  11. material protection

    National Nuclear Security Administration (NNSA)

    %2A en Office of Weapons Material Protection http:www.nnsa.energy.govaboutusourprogramsnonproliferationprogramofficesinternationalmaterialprotectionandcooperation-1

  12. Critical Materials:

    Office of Environmental Management (EM)

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

  13. Materials Scientist

    Broader source: Energy.gov [DOE]

    Alternate Title(s):Materials Research Engineer; Metallurgical/Chemical Engineer; Product Development Manager;

  14. NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 FAILURE MODES AND EFFECTS ANALYSIS

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 10 Dated: November 2014 Prepared By: Name/WBS Signature Name: ________________________________________________ Ron Strykowsky, NSTX Upgrade Project Manager #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71

  15. Estimating Overall Risk of Dam Failure: Practical Considerations in Combining Failure Probabilities ANCOLD 2003 Risk Workshop Page 1

    E-Print Network [OSTI]

    Bowles, David S.

    Estimating Overall Risk of Dam Failure: Practical Considerations in Combining Failure Probabilities ANCOLD 2003 Risk Workshop Page 1 ESTIMATING OVERALL RISK OF DAM FAILURE: PRACTICAL CONSIDERATIONS With the move to a risk based approach to dam safety there has been a concomitant focus on estimating

  16. Timing analysis of PWR fuel pin failures

    SciTech Connect (OSTI)

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Straka, M. (Halliburton NUS, Idaho Falls, ID (United States))

    1992-09-01

    Research has been conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin bumup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PFL/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design bumup. Using peaking factors commensurate widi actual bumups would result in longer intervals for both reactor designs. This document also contains appendices A through J of this report.

  17. Reduce Steam Trap Failures at Chambers Works 

    E-Print Network [OSTI]

    Kouba, C.

    2010-01-01

    Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central Maintenance Mechanic), Rick... is it sustainable HOW we went about finding a solution What do you have learn from this 10/20/2010 3 Six Sigma Methodology was KEY to success Savings: $1MM annualized in only 6 months! 10/20/2010 4Define: Project CTQ?s Customer: Chambers Works site Voice...

  18. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel: A Computational

    E-Print Network [OSTI]

    Grujicic, Mica

    -welding of a prototypical high-hardness armor-grade martensitic steel, MIL A46100. The model predictions concerning-tempered, high-hardness, low-alloy martensitic, ar- mor-grade steel). A summary of Johnson-Cook material- modelBallistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel

  19. Materials Science

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

    Database (TPMD) Aerospace Structural Metals Database (ASMD) Damage Tolerant Design Handbook (DTDH) Microelectronics Packaging Materials Database (MPMD) Structural Alloys...

  20. Bladder Cancer Patterns of Pelvic Failure: Implications for Adjuvant Radiation Therapy

    SciTech Connect (OSTI)

    Baumann, Brian C.; Guzzo, Thomas J.; He Jiwei; Vaughn, David J.; Keefe, Stephen M.; Vapiwala, Neha; Deville, Curtiland; Bekelman, Justin E.; Tucker, Kai; Hwang, Wei-Ting; Malkowicz, S. Bruce; Christodouleas, John P.

    2013-02-01

    Purpose: Local-regional failures (LFs) after cystectomy with or without chemotherapy are common in locally advanced disease. Adjuvant radiation therapy (RT) could reduce LFs, but toxicity has discouraged its use. Modern RT techniques with improved normal tissue sparing have rekindled interest but require knowledge of pelvic failure patterns to design treatment volumes. Methods and Materials: Five-year LF rates after radical cystectomy plus pelvic node dissection with or without chemotherapy were determined for 8 pelvic sites among 442 urothelial bladder carcinoma patients. The impact of pathologic stage, margin status, nodal involvement, and extent of node dissection on failure patterns was assessed using competing risk analysis. We calculated the percentage of patients whose sites of LF would have been completely encompassed within various hypothetical clinical target volumes (CTVs) for postoperative radiation. Results: Compared with stage {<=}pT2, stage {>=}pT3 patients had higher 5-year LF rates in virtually all pelvic sites. Among stage {>=}pT3 patients, margin status significantly altered the failure pattern whereas extent of node dissection and nodal positivity did not. In stage {>=}pT3 patients with negative margins, failure occurred predominantly in the iliac/obturator nodes and uncommonly in the cystectomy bed and/or presacral nodes. Of these patients in whom failure subsequently occurred, 76% would have had all LF sites encompassed within CTVs covering only the iliac/obturator nodes. In stage {>=}pT3 with positive margins, cystectomy bed and/or presacral nodal failures increased significantly. Only 57% of such patients had all LF sites within CTVs limited to the iliac/obturator nodes, but including the cystectomy bed and presacral nodes in the CTV when margins were positive increased the percentage of LFs encompassed to 91%. Conclusions: Patterns of failure within the pelvis are summarized to facilitate design of adjuvant RT protocols. These data suggest that RT should target at least the iliac/obturator nodes in stage {>=}pT3 with negative margins; coverage of the presacral nodes and cystectomy bed may be necessary for stage {>=}pT3 with positive margins.

  1. Power Grid Defense Against Malicious Cascading Failure

    E-Print Network [OSTI]

    Shakarian, Paulo; Lindelauf, Roy

    2014-01-01

    An adversary looking to disrupt a power grid may look to target certain substations and sources of power generation to initiate a cascading failure that maximizes the number of customers without electricity. This is particularly an important concern when the enemy has the capability to launch cyber-attacks as practical concerns (i.e. avoiding disruption of service, presence of legacy systems, etc.) may hinder security. Hence, a defender can harden the security posture at certain power stations but may lack the time and resources to do this for the entire power grid. We model a power grid as a graph and introduce the cascading failure game in which both the defender and attacker choose a subset of power stations such as to minimize (maximize) the number of consumers having access to producers of power. We formalize problems for identifying both mixed and deterministic strategies for both players, prove complexity results under a variety of different scenarios, identify tractable cases, and develop algorithms f...

  2. FailureSense: Detecting Sensor Failure using Electrical Appliances in the Home

    E-Print Network [OSTI]

    Stankovic, John A.

    in smart homes for various applications, including home health care, energy management, and se- curity@cs.virginia.edu Abstract--With the proliferation of inexpensive sensors, sensors are increasingly being used in smart homes risk of various types of sensor failure. Motivated by real examples, we develop new schemes to detect

  3. A REVIEW OF SOFTWARE-INDUCED FAILURE EXPERIENCE.

    SciTech Connect (OSTI)

    CHU, T.L.; MARTINEZ-GURIDI, G.; YUE, M.; LEHNER, J.

    2006-09-01

    We present a review of software-induced failures in commercial nuclear power plants (NPPs) and in several non-nuclear industries. We discuss the approach used for connecting operational events related to these failures and the insights gained from this review. In particular, we elaborate on insights that can be used to model this kind of failure in a probabilistic risk assessment (PRA) model. We present the conclusions reached in these areas.

  4. Link failure detection in a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Blocksome, Michael A. (Rochester, MN); Megerian, Mark G. (Rochester, MN); Smith, Brian E. (Rochester, MN)

    2010-11-09

    Methods, apparatus, and products are disclosed for link failure detection in a parallel computer including compute nodes connected in a rectangular mesh network, each pair of adjacent compute nodes in the rectangular mesh network connected together using a pair of links, that includes: assigning each compute node to either a first group or a second group such that adjacent compute nodes in the rectangular mesh network are assigned to different groups; sending, by each of the compute nodes assigned to the first group, a first test message to each adjacent compute node assigned to the second group; determining, by each of the compute nodes assigned to the second group, whether the first test message was received from each adjacent compute node assigned to the first group; and notifying a user, by each of the compute nodes assigned to the second group, whether the first test message was received.

  5. Sandia Energy - Failure Mode and Effect Analysis (FMEA) Tutorial

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

    and Effect Analysis (FMEA) Tutorial Home Stationary Power Energy Conversion Efficiency Solar Energy Photovoltaics PV Systems Reliability Tutorial on FMEA Process Failure Mode...

  6. The Sandia MEMS Passive Shock Sensor : FY08 failure analysis...

    Office of Scientific and Technical Information (OSTI)

    analysis activities. Citation Details In-Document Search Title: The Sandia MEMS Passive Shock Sensor : FY08 failure analysis activities. No abstract prepared. Authors:...

  7. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01

    FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Theand breakage of the superconductor. The UPA circuit melted

  8. Wind Turbine Gearbox Failure Modes - A Brief (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.; McDade, M.; Errichello, R.

    2011-10-01

    Wind turbine gearboxes are not always meeting 20-year design life. Premature failure of gearboxes increases cost of energy, turbine downtime, unplanned maintenance, gearbox replacement and rebuild, and increased warranty reserves. The problem is widespread, affects most Original Equipment Manufacturers, and is not caused by manufacturing practices. There is a need to improve gearbox reliability and reduce turbine downtime. The topics of this presentation are: GRC (Gearbox Reliability Collaborative) technical approach; Gearbox failure database; Recorded incidents summary; Top failure modes for bearings; Top failure modes for gears; GRC test gearbox; Bearing nomenclature; Test history; Real damage; Gear sets; Bearings; Observations; and Summary. 5 refs.

  9. Modeling shear failure and permeability enhancement due to coupled...

    Office of Scientific and Technical Information (OSTI)

    enhancement due to coupled Thermal-Hydrological-Mechanical processes in Enhanced Geothermal Reservoirs Citation Details In-Document Search Title: Modeling shear failure and...

  10. Pattern of Failure After Limited Margin Radiotherapy and Temozolomide for Glioblastoma

    SciTech Connect (OSTI)

    McDonald, Mark W.; Shu, Hui-Kuo G.; Curran, Walter J.; Crocker, Ian R.

    2011-01-01

    Purpose: To evaluate the pattern of failure after limited margin radiotherapy for glioblastoma. Methods and Materials: We analyzed 62 consecutive patients with newly diagnosed glioblastoma treated between 2006 and 2008 with standard fractionation to a total dose of 60Gy with concurrent temozolomide (97%) or arsenic trioxide (3%). The initial clinical target volume included postoperative T2 abnormality with a median margin of 0.7cm. The boost clinical target volume included residual T1-enhancing tumor and resection cavity with a median margin of 0.5cm. Planning target volumes added a 0.3- or 0.5-cm margin to clinical target volumes. The total boost planning target volume (PTV{sub boost}) margin was 1cm or less in 92% of patients. The volume of recurrent tumor (new T1 enhancement) was categorized by the percent within the 60-Gy isodose line as central (>95%), infield (81-95%), marginal (20-80%), or distant (<20%). For comparison, an initial planning target volume with a 2-cm margin and PTV{sub boost} with a 2.5-cm margin were created for each patient. Results: With a median follow-up of 12 months, radiographic tumor progression developed in 43 of 62 patients. Imaging was available for analysis in 41: 38 (93%) had central or infield failure, 2 (5%) had marginal failure, and 1 (2%) had distant failure relative to the 60-Gy isodose line. The treated PTV{sub boost} (median, 140cm{sup 3}) was, on average, 70% less than the PTV{sub boost} with a 2.5-cm margin (median, 477cm{sup 3}) (p < 0.001). Conclusions: A PTV{sub boost} margin of 1cm or less did not appear to increase the risk of marginal and/or distant tumor failures compared with other published series. With careful radiation planning and delivery, it appears that treatment margins for glioblastoma can be reduced.

  11. Failure Predictions for VHTR Core Components using a Probabilistic Contiuum Damage Mechanics Model

    SciTech Connect (OSTI)

    Fok, Alex

    2013-10-30

    The proposed work addresses the key research need for the development of constitutive models and overall failure models for graphite and high temperature structural materials, with the long-term goal being to maximize the design life of the Next Generation Nuclear Plant (NGNP). To this end, the capability of a Continuum Damage Mechanics (CDM) model, which has been used successfully for modeling fracture of virgin graphite, will be extended as a predictive and design tool for the core components of the very high- temperature reactor (VHTR). Specifically, irradiation and environmental effects pertinent to the VHTR will be incorporated into the model to allow fracture of graphite and ceramic components under in-reactor conditions to be modeled explicitly using the finite element method. The model uses a combined stress-based and fracture mechanics-based failure criterion, so it can simulate both the initiation and propagation of cracks. Modern imaging techniques, such as x-ray computed tomography and digital image correlation, will be used during material testing to help define the baseline material damage parameters. Monte Carlo analysis will be performed to address inherent variations in material properties, the aim being to reduce the arbitrariness and uncertainties associated with the current statistical approach. The results can potentially contribute to the current development of American Society of Mechanical Engineers (ASME) codes for the design and construction of VHTR core components.

  12. Preventing aneuploidy and the consequences of failure

    E-Print Network [OSTI]

    Prabhu, Vineet R. (Vineet Ranjan)

    2009-01-01

    The maintenance and transmission of genetic material is critical for the survival of cells and organisms. Sexually reproducing diploid organisms undergo meiosis to produce haploid gametes, so that the resulting progeny are ...

  13. Scintillator material

    DOE Patents [OSTI]

    Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

    1994-01-01

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  14. Scintillator material

    DOE Patents [OSTI]

    Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

    1992-01-01

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  15. Scintillator material

    DOE Patents [OSTI]

    Anderson, D.F.; Kross, B.J.

    1994-06-07

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  16. Scintillator material

    DOE Patents [OSTI]

    Anderson, D.F.; Kross, B.J.

    1992-07-28

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  17. material recovery

    National Nuclear Security Administration (NNSA)

    dispose of dangerous nuclear and radiological material, and detect and control the proliferation of related WMD technology and expertise.

  18. Materials for solid state lighting

    SciTech Connect (OSTI)

    Johnson, S.G.; Simmons, J.A.

    2002-03-26

    Dramatic improvement in the efficiency of inorganic and organic light emitting diodes (LEDs and OLEDs) within the last decade has made these devices viable future energy efficient replacements for current light sources. However, both technologies must overcome major technical barriers, requiring significant advances in material science, before this goal can be achieved. Attention will be given to each technology associated with the following major areas of material research: (1) material synthesis, (2) process development, (3) device and defect physics, and (4) packaging. The discussion on material synthesis will emphasize the need for further development of component materials, including substrates and electrodes, necessary for improving device performance. The process technology associated with the LEDs and OLEDs is very different, but in both cases it is one factor limiting device performance. Improvements in process control and methodology are expected to lead to additional benefits of higher yield, greater reliability and lower costs. Since reliability and performance are critical to these devices, an understanding of the basic physics of the devices and device failure mechanisms is necessary to effectively improve the product. The discussion will highlight some of the more basic material science problems remaining to be solved. In addition, consideration will be given to packaging technology and the need for the development of novel materials and geometries to increase the efficiencies and reliability of the devices. The discussion will emphasize the performance criteria necessary to meet lighting applications, in order to illustrate the gap between current status and market expectations for future product.

  19. Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels

    SciTech Connect (OSTI)

    Lu, Hongbing; Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott

    2014-01-09

    Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear fuels are critical to understand the burnup, and thus the fuel efficiency.

  20. Cermet materials

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID)

    2008-12-23

    A self-cleaning porous cermet material, filter and system utilizing the same may be used in filtering particulate and gaseous pollutants from internal combustion engines having intermetallic and ceramic phases. The porous cermet filter may be made from a transition metal aluminide phase and an alumina phase. Filler materials may be added to increase the porosity or tailor the catalytic properties of the cermet material. Additionally, the cermet material may be reinforced with fibers or screens. The porous filter may also be electrically conductive so that a current may be passed therethrough to heat the filter during use. Further, a heating element may be incorporated into the porous cermet filter during manufacture. This heating element can be coated with a ceramic material to electrically insulate the heating element. An external heating element may also be provided to heat the cermet filter during use.

  1. Composite material

    DOE Patents [OSTI]

    Hutchens, Stacy A. (Knoxville, TN); Woodward, Jonathan (Solihull, GB); Evans, Barbara R. (Oak Ridge, TN); O'Neill, Hugh M. (Knoxville, TN)

    2012-02-07

    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  2. CRITICALITY IN A CASCADING FAILURE BLACKOUT MODEL Dusko P. Nedic

    E-Print Network [OSTI]

    n i f i - cant risk of large blackouts. Keywords: reliability, security, risk, power law 1, for all these types of interac- tion, the risk of cascading failure generally becomes more severe increases? Previous work suggests that a cascading failure does not gradually and uniformly be- come more

  3. Optimal Test Distributions for Software Failure Cost Walter J. Gutjahr

    E-Print Network [OSTI]

    Gutjahr, Walter

    Optimal Test Distributions for Software Failure Cost Estimation Walter J. Gutjahr Department, reliability estimation, risk assessment, software failure costs, software reliability, software testing. I in a software quality assurance process, to be performed after a testing phase oriented on fault detection. Let

  4. Coding Hazardous Tree Failures for a Data Management System

    E-Print Network [OSTI]

    Standiford, Richard B.

    Terms: hazard trees; hazard reduction; recreation areas; urban forestry; safety standards; dataCoding Hazardous Tree Failures for a Data Management System Lee A. Paine PACIFIC SOUTHWEST hazardous tree failures for a data management system. Gen. Tech. Rep. PSW-29, 108 p., illus. Pacific

  5. A UNIFIED FAILURE/DAMAGE APPROACH TO BATTLE DAMAGE REGENERATION

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A UNIFIED FAILURE/DAMAGE APPROACH TO BATTLE DAMAGE REGENERATION : APPLICATION TO GROUND MILITARY-availability. Military weapon systems availability can be affected by system failures or by damage to the system damage into account in their more general dependability studies. This paper takes a look at the issues

  6. Modeling Space Shuttle Software Failures at Varying Criticality Levels

    E-Print Network [OSTI]

    Morgan, Joseph

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

  7. FAILURE MODES AND EFFECTS ANALYSIS Dated: May 27, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    1 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 7 Dated: May 27, 2010 Prepared By: Name.07.13 09:11:02 -04'00' #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-7 / p. 2 of 120 2 Table

  8. Fast Recovery From Link Failures in Ethernet Networks

    E-Print Network [OSTI]

    Ramasubramanian, Srinivasan

    1 Fast Recovery From Link Failures in Ethernet Networks Abishek Gopalan and Srinivasan,srini}@ece.arizona.edu Abstract--Fast-recovery from link failures is a well-studied topic in IP networks. Employing fast, switches employ backward learning to populate the forwarding table entries. Thus, any fast recovery

  9. Common Trends in Software Fault and Failure Data

    E-Print Network [OSTI]

    Goseva-Popstojanova, Katerina

    Common Trends in Software Fault and Failure Data Maggie Hamill, Member, IEEE, and Katerina Goseva with the findings from related studies. The consistency of several main trends across software systems in this paper-Popstojanova, Senior Member, IEEE Abstract--The benefits of the analysis of software faults and failures have been

  10. The role of environmental assumptions in failures of DNA nanosystems

    E-Print Network [OSTI]

    Lutz, Robyn R.

    describe the structure of a failure catalog for DNA nanosystems that we have prototyped for use by molecular programmers. We hypothesize that the failure frame approach and catalog can be broadly useful if and only if the plane is moving on the runway [4]. In fact, when the plane was aquaplaning on a water

  11. Financial Cash Flow Determinants of Company Failure in the Construction

    E-Print Network [OSTI]

    Kamat, Vineet R.

    Financial Cash Flow Determinants of Company Failure in the Construction Industry by Ihab to thank my family. They have always been a source of inspiration, encouragement and love, and I would xi Chapter 1: Introduction 1 1.1 Construction Company Failure Statistics 6 1.2 Overview

  12. Software, the Urn Model, and Failure Peter Bernard Ladkin

    E-Print Network [OSTI]

    Ladkin, Peter B.

    for UK nuclear power plant protection systems using statistical methods [Lit10]. It is the basis for some to perform design function on demand Number of observed demands without failure for a confidence level of 99-History Requirements for On-Demand Functions Acceptable probability of failure to perform design function per hour

  13. Energy Efficiency and Renewables: Market and Behavioral Failures

    ScienceCinema (OSTI)

    James Sweeney

    2010-09-01

    Thursday, January 28, 2010: Policies to promote renewable energy and energy efficiency have been gaining momentum throughout the world, often justified by environmental and energy security concerns. This presentation first talks about energy efficiency options, then delves into the economic motivation for energy efficiency and renewable energy policies by articulating the classes of relevant behavioral failures and market failures. Such behavioral and market failures may vary intertemporally or atemporally; the temporal structure and the extent of the failures are the critical considerations in the development of energy policies. The talk discusses key policy instruments and assess the extent to which they are well-suited to correct for failures with different structures. http://eetd.lbl.gov/dls/lecture-01-28...

  14. Recovery systems must save state before a failure occurs to enable the system to recover from the failure. However,

    E-Print Network [OSTI]

    Chen, Peter M.

    Abstract Recovery systems must save state before a failure occurs to enable the system to recover from the failure. However, recovery will fail if the recovery system saves any state corrupted by the fault. The frequency and comprehensive- ness of how a recovery system saves state has a major effect

  15. Nuclear fuel elements made from nanophase materials

    DOE Patents [OSTI]

    Heubeck, Norman B. (Schenectady, NY)

    1998-01-01

    A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain related failure even at high temperatures, in the order of about 3000.degree. F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all-ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite. The nuclear reactor so constructed has a number of high strength fuel particles, a nanophase structural material for supporting a fuel rod at high temperature, a configuration to allow passive cooling in the event of a primary cooling system failure, an ability to retain a coolable geometry even at high temperatures, an ability to resist generation of hydrogen gas, and a configuration having good nuclear, corrosion, and mechanical characteristics.

  16. Nuclear fuel elements made from nanophase materials

    DOE Patents [OSTI]

    Heubeck, N.B.

    1998-09-08

    A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain related failure even at high temperatures, in the order of about 3000 F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all-ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite. The nuclear reactor so constructed has a number of high strength fuel particles, a nanophase structural material for supporting a fuel rod at high temperature, a configuration to allow passive cooling in the event of a primary cooling system failure, an ability to retain a coolable geometry even at high temperatures, an ability to resist generation of hydrogen gas, and a configuration having good nuclear, corrosion, and mechanical characteristics. 5 figs.

  17. Complex Materials

    SciTech Connect (OSTI)

    Cooper, Valentino

    2014-04-17

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  18. Complex Materials

    ScienceCinema (OSTI)

    Cooper, Valentino

    2014-05-23

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  19. material removal

    National Nuclear Security Administration (NNSA)

    %2A en Nuclear Material Removal http:www.nnsa.energy.govaboutusourprogramsdnnm3remove

    Pag...

  20. Propulsion materials

    SciTech Connect (OSTI)

    Wall, Edward J.; Sullivan, Rogelio A.; Gibbs, Jerry L.

    2008-01-01

    The Department of Energy’s (DOE’s) Office of Vehicle Technologies (OVT) is pleased to introduce the FY 2007 Annual Progress Report for the Propulsion Materials Research and Development Program. Together with DOE national laboratories and in partnership with private industry and universities across the United States, the program continues to engage in research and development (R&D) that provides enabling materials technology for fuel-efficient and environmentally friendly commercial and passenger vehicles.

  1. Size-dependent mechanical properties of beta-structures in protein materials

    E-Print Network [OSTI]

    Keten, Sinan

    2010-01-01

    Protein materials such as spider silk can be exceptionally strong, and they can stretch tremendously before failure. Notably, silks are made entirely of proteins, which owe their structure and stability to weak molecular ...

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

    SciTech Connect (OSTI)

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

    1998-12-31

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

  3. Investigation of Possible Wellbore Cement Failures During Hydraulic Fracturing Operations

    SciTech Connect (OSTI)

    Kim, Jihoon; Moridis, George

    2014-11-01

    We model and assess the possibility of shear failure, using the Mohr-Coulomb model ? along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, low cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a high-quality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.

  4. Vulnerability Assessment for Cascading Failures in Electric Power Systems

    SciTech Connect (OSTI)

    Baldick, R.; Chowdhury, Badrul; Dobson, Ian; Dong, Zhao Yang; Gou, Bei; Hawkins, David L.; Huang, Zhenyu; Joung, Manho; Kim, Janghoon; Kirschen, Daniel; Lee, Stephen; Li, Fangxing; Li, Juan; Li, Zuyi; Liu, Chen-Ching; Luo, Xiaochuan; Mili, Lamine; Miller, Stephen; Nakayama, Marvin; Papic, Milorad; Podmore, Robin; Rossmaier, John; Schneider, Kevin P.; Sun, Hongbin; Sun, Kai; Wang, David; Wu, Zhigang; Yao, Liangzhong; Zhang, Pei; Zhang, Wenjie; Zhang, Xiaoping

    2008-09-10

    Cascading failures present severe threats to power grid security, and thus vulnerability assessment of power grids is of significant importance. Focusing on analytic methods, this paper reviews the state of the art of vulnerability assessment methods in the context of cascading failures in three categories: steady-state modeling based analysis; dynamic modeling analysis; and non-traditional modeling approaches. The impact of emerging technologies including phasor technology, high-performance computing techniques, and visualization techniques on the vulnerability assessment of cascading failures is then addressed, and future research directions are presented.

  5. Cascade Failure in a Phase Model of Power Grids

    E-Print Network [OSTI]

    Sakaguchi, Hidetsugu

    2012-01-01

    We propose a phase model to study cascade failure in power grids composed of generators and loads. If the power demand is below a critical value, the model system of power grids maintains the standard frequency by feedback control. On the other hand, if the power demand exceeds the critical value, an electric failure occurs via step out (loss of synchronization) or voltage collapse. The two failures are incorporated as two removal rules of generator nodes and load nodes. We perform direct numerical simulation of the phase model on a scale-free network and compare the results with a mean-field approximation.

  6. Helium pressures in RHIC vacuum cryostats and relief valve requirements from magnet cooling line failure

    SciTech Connect (OSTI)

    Liaw, C.J.; Than, Y.; Tuozzolo, J.

    2011-03-28

    A catastrophic failure of the RHIC magnet cooling lines, similar to the LHC superconducting bus failure incident, would pressurize the insulating vacuum in the magnet and transfer line cryostats. Insufficient relief valves on the cryostats could cause a structural failure. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the vacuum cryostat and discharging via the reliefs into the RHIC tunnel, had been developed to calculate the helium pressure inside the cryostat. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces were included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Existing relief valve sizes were reviewed to make sure that the maximum stresses, caused by the calculated maximum pressures inside the cryostats, did not exceed the allowable stresses, based on the ASME Code B31.3 and ANSYS results. The conclusions are as follows: (1) The S/F simulation results show that the highest internal pressure in the cryostats, due to the magnet line failure, is {approx}37 psig (255115 Pa); (2) Based on the simulation, the temperature on the cryostat chamber, INJ Q8-Q9, could drop to 228 K, which is lower than the material minimum design temperature allowed by the Code; (3) Based on the ASME Code and ANSYS results, the reliefs on all the cryostats inside the RHIC tunnel are adequate to protect the vacuum chambers when the magnet cooling lines fail; and (4) In addition to the pressure loading, the thermal deformations, due to the temperature decrease on the cryostat chambers, could also cause a high stress on the chamber, if not properly supported.

  7. Effect of the porosity on the fracture surface roughness of sintered materials: From anisotropic to isotropic self-affine scaling

    E-Print Network [OSTI]

    Tristan Cambonie; Jonathan Bares; Lamine Hattali; Daniel Bonamy; Véronique Lazarus; Harold Auradou

    2015-01-16

    To unravel how the microstructure affects the fracture surface roughness in heterogeneous brittle solids like rocks or ceramics, we characterized the roughness statistics of post-mortem fracture surfaces in home-made materials of adjustable microstructure length-scale and porosity, obtained by sintering monodisperse polystyrene beads. Beyond the characteristic size of disorder, the roughness profiles are found to exhibit self-affine scaling features evolving with porosity. Starting from a null value and increasing the porosity, we quantitatively modify the self-affine scaling properties from anisotropic (at low porosity) to isotropic (for porosity larger than 10 %).

  8. Hardfacing material

    DOE Patents [OSTI]

    Branagan, Daniel J. (Iona, ID)

    2012-01-17

    A method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of boron, carbon, silicon and phosphorus. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

  9. Autonomous thruster failure recovery on underactuated spacecraft using model predictive control

    E-Print Network [OSTI]

    Pong, Christopher Masaru

    Thruster failures historically account for a large percentage of failures that have occurred on orbit. These failures are typically handled through redundancy, however, with the push to using smaller, less expensive ...

  10. Congestive heart failure: treat the disease, not the symptom: return to normalcy/Part II--the experimental approach.

    E-Print Network [OSTI]

    Buckberg, Gerald D

    2007-01-01

    Number: Title: Congestive heart failure: treat the diseaseinvited) TITLE: Congestive heart failure: treat the diseasetreatment of congestive heart failure due to post-infarction

  11. Modeling of Brittle to Ductile Transition in BCC metals : : Strain Rate and Temperature dependence in [alpha]-Iron and Tantalum Monocrystals

    E-Print Network [OSTI]

    Karandikar, Keyur Kashinath

    2013-01-01

    Elastic and Plastic Behavior Mechanical properties of the1.1 Mechanical properties of Materials: Elastic and Plasticproperty that distinguishes the above modes is the plastic

  12. Terrestrial Photovoltaic Module Accelerated Test-To-Failure Protocol

    SciTech Connect (OSTI)

    Osterwald, C. R.

    2008-03-01

    This technical report documents a test-to-failure protocol that may be used to obtain quantitative information about the reliability of photovoltaic modules using accelerated testing in environmental temperature-humidity chambers.

  13. Transport and Failure in Li-ion Batteries | Stanford Synchrotron...

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

    Transport and Failure in Li-ion Batteries Monday, February 13, 2012 - 1:30pm SSRL Conference Room 137-322 Stephen J. Harris, General Motors R&D While battery performance is well...

  14. Failure Mode, Effects and Criticality Analysis -Array D

    E-Print Network [OSTI]

    Rathbun, Julie A.

    , and have verified that Receivers A and B are failure isolated. This FMECA reflects the F ACI configuration 3 4 5 6 7 8 9 10 11 12 13 14... ·~:=.fRET DRAWING IN ACCORDANCE WITH STANDARDS PRESCRIBED

  15. Pathogenesis of the Erythroid Failure in Diamond Blackfan Anemia

    E-Print Network [OSTI]

    Sieff, Colin A.

    Diamond Blackfan anaemia (DBA) is a severe congenital failure of erythropoiesis. Despite mutations in one of several ribosome protein genes, including RPS19, the cause of the erythroid specificity is still a mystery. We ...

  16. RECOGNITION OF BEARING FAILURES USING WAVELETS AND NEURAL NETWORKS

    E-Print Network [OSTI]

    Duin, Robert P.W.

    ­ scribed and investigated for their usefulness in the recognition of bearing failures in a submersible pump cracks give rise to relative short­time transients in the vibra­ tion signal. As wear progresses

  17. Failure Mode and Sensitivity Analysis of Gas Lift Valves

    E-Print Network [OSTI]

    Gilbertson, Eric W.

    Gas-lifted oil wells are susceptible to failure through malfunction of gas lift valves. This is a growing concern as offshore wells are drilled thousands of meters below the ocean floor in extreme temperature and pressure ...

  18. Queueing systems subject to random server failures: an approximation 

    E-Print Network [OSTI]

    Matis, Timothy

    1998-01-01

    research into finding exact or approximate methods that adjust key performance measures of a system to reflect server failures. Many of the methods that have been developed suffer either from a high degree of computational complexity or from tight...

  19. Geographically Correlated Failures in Power Networks Survivability Analysis

    E-Print Network [OSTI]

    Hay, David

    . 2003 blackout in the Northeastern United States and Canada [32]) demonstrated that large-scale failures is dedicated to identifying Fig. 1. The development of the Sept. 8, 2011 San Diego blackout according to [11

  20. Three essays on business failure: causality and prediction 

    E-Print Network [OSTI]

    Zhang, Jin

    2009-05-15

    This dissertation investigates three issues on business failure causality and prediction. First, a nonlinear model for mathematical programming based discriminant analysis is studied. This study proposes a nonlinear model ...

  1. Making Sense of the Social Aspects of Business Failure 

    E-Print Network [OSTI]

    Heinze, Ilka

    2011-11-23

    This study examines the process of entrepreneurial sense-making of business failure in the context of their social environment. Transcripts of semi-structured interviews with six entrepreneurs who experienced business ...

  2. Performance of wireless sensor networks under random node failures

    SciTech Connect (OSTI)

    Bradonjic, Milan [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Feng, Pan [Los Alamos National Laboratory

    2011-01-28

    Networks are essential to the function of a modern society and the consequence of damages to a network can be large. Assessing network performance of a damaged network is an important step in network recovery and network design. Connectivity, distance between nodes, and alternative routes are some of the key indicators to network performance. In this paper, random geometric graph (RGG) is used with two types of node failure, uniform failure and localized failure. Since the network performance are multi-facet and assessment can be time constrained, we introduce four measures, which can be computed in polynomial time, to estimate performance of damaged RGG. Simulation experiments are conducted to investigate the deterioration of networks through a period of time. With the empirical results, the performance measures are analyzed and compared to provide understanding of different failure scenarios in a RGG.

  3. Materials compatibility.

    SciTech Connect (OSTI)

    Somerday, Brian P.

    2010-04-01

    Objectives are to enable development and implementation of codes and standards for H{sub 2} containment components: (1) Evaluate data on mechanical properties of materials in H{sub 2} gas - Technical Reference on Hydrogen Compatibility of Materials; (2) Generate new benchmark data on high-priority materials - Pressure vessel steels, stainless steels; and (3) Establish procedures for reliable materials testing - Sustained-load cracking, fatigue crack propagation. Summary of this presentation are: (1) Completed measurement of cracking thresholds (K{sub TH}) for Ni-Cr-Mo pressure vessel steels in high-pressure H{sub 2} gas - K{sub TH} measurements required in ASME Article KD-10 (2) Crack arrest test methods appear to yield non-conservative results compared to crack initiation test methods - (a) Proposal to insert crack initiation test methods in Article KD-10 will be presented to ASME Project Team on Hydrogen Tanks, and (b) Crack initiation methods require test apparatus designed for dynamic loading of specimens in H{sub 2} gas; and (3) Demonstrated ability to measure fatigue crack growth of pressure vessel steels in high-pressure H{sub 2} gas - (a) Fatigue crack growth data in H{sub 2} required in ASME Article KD-10, and (b) Test apparatus is one of few in U.S. or abroad for measuring fatigue crack growth in >100 MPa H{sub 2} gas.

  4. Development of a failure prediction method for damaged tubular members 

    E-Print Network [OSTI]

    Ritter, James Edward

    1992-01-01

    DEVELOPMENT OF A FAILURE PREDICTION METHOD FOR DAMAGED TUBULAR MEMBERS A Thesis by ZAMES EDWARD RITTER Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE May 1992 Major Subject: Civil Engineering DEVELOPMEMT OF A FAILURE PREDICTION METHOD FOR DAMAGED TUBULAR MEMBER8 A Thesis by JAMES EDWARD RITTER Approved as to style and content by: T ry L. Kohutek (Chair of Committee) Loren D. Lutes...

  5. On-clip high frequency reliability and failure test structures

    DOE Patents [OSTI]

    Snyder, Eric S. (Albuquerque, NM); Campbell, David V. (Albuquerque, NM)

    1997-01-01

    Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer.

  6. The Failure of Environmental Education [And How We Can Fix It

    E-Print Network [OSTI]

    Hamilton-Smith, Elery

    2011-01-01

    The Failure of Environmental Education [And How We Can FixThe Failure of Environmental Education [And How We Can Fix

  7. Localization and activation of CaMKII delta isoforms and their involvement in heart failure

    E-Print Network [OSTI]

    Mishra, Shikha

    2010-01-01

    hypertrophy and heart failure ..CaMKII mediated hypertrophy and heart failure .. I.F.II.C. Preparation of heart tissue extract and cell lysate

  8. Failure of the Shockley-Haynes Mobility Experiment with organic semiconducting materials 

    E-Print Network [OSTI]

    Boehme, Hollis Clyde

    1961-01-01

    of the teflon cylinder was 0. 20$ cm + 0. 00$ cm whioh was slight- ly smaller than the graphite rods used, This arrapgement provided an airtight seal to prevent the sublimation of iodine from the samples after pressing Small holes were drilled through...-iodine was lower than that reported, The upper limit of 3000 lb/i. n for the pressure used to 2 oompress the samples was dictated by the graphite rods used and the wall thickness of the teflon oylinders. Pressures above $000 lb/in oaused either the ends...

  9. Injectable Materials for the Treatment of Myocardial Infarction and Heart Failure: The Promise of Decellularized Matrices

    E-Print Network [OSTI]

    Singelyn, Jennifer M.; Christman, Karen L.

    2010-01-01

    studies involved direct epicardial injection while a patientmodels, via direct epicardial injection [23, 25– 27, 43,tissue upon direct epicardial injection, with pore size of ~

  10. Real-Time Quantitative Imaging of Failure Events in Materials Under Load at

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) by Carbon-RichProton DeliveryRadioactiveRare |Real-Time

  11. Machine Design -2 The figure below shows a picture of the splined end of a failed half-shaft. The fatigue failure occurred at the

    E-Print Network [OSTI]

    Battaglia, Francine

    Machine Design - 2 The figure below shows a picture of the splined end of a failed half-shaft. The fatigue failure occurred at the snap-ring groove. The half-shaft transmits engine torque on acceleration = +1617 in-lbf. The half-shaft material is a heat-treated, case-hardened 4340 steel, Sy = 234 kpsi, Sut

  12. An Attempt to Calibrate and Validate a Simple Ductile Failure Model Against Axial-Torsion Experiments on Al 6061-T651.

    SciTech Connect (OSTI)

    Reedlunn, Benjamin; Lu, Wei-Yang

    2015-01-01

    This report details a work in progress. We have attempted to calibrate and validate a Von Mises plasticity model with the Johnson-Cook failure criterion ( Johnson & Cook , 1985 ) against a set of experiments on various specimens of Al 6061-T651. As will be shown, the effort was not successful, despite considerable attention to detail. When the model was com- pared against axial-torsion experiments on tubes, it over predicted failure by 3 x in tension, and never predicted failure in torsion, even when the tube was twisted by 4 x further than the experiment. While this result is unfortunate, it is not surprising. Ductile failure is not well understood. In future work, we will explore whether more sophisticated material mod- els of plasticity and failure will improve the predictions. Selecting the appropriate advanced material model and interpreting the results of said model are not trivial exercises, so it is worthwhile to fully investigate the behavior of a simple plasticity model before moving on to an anisotropic yield surface or a similarly complicated model.

  13. Identification of reactor vessel failures using spatiotemporal neural networks

    SciTech Connect (OSTI)

    Roh, C.H.; Chang, H.S.; Kim, H.G.; Chang, S.H. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Nuclear Engineering

    1996-12-01

    Identification of vessel failures provides operators and technical support center personnel with important information to manage severe accidents in a nuclear power plant. It may be very difficult, however, for operators to identify a reactor vessel failure simply by watching temporal trends of some parameters because they have not experienced severe accidents. Therefore, the authors propose a methodology on the identification of pressurized water reactor (PWR) vessel failure for severe accident management using spatiotemporal neural network (STN). STN can deal directly with the spatial and temporal aspects of input signals and can well identify a time-varying problem. Target patterns of seven parameter signals were generated for training the network from the modular accident in nuclear power plants. They integrated MAAP code with STN in on-line system to mimic real accident situation in nuclear power plants. Using new pattern of signals that had never been used for training, the identification capability of STN was tested in a real-time manner. At the tests, STN developed in this study demonstrated acceptable performance in identifying the occurrence of a vessel failure. It is found that STN techniques can be extended to the identification of other key events such as onset of core uncovery, coremelt initiation, containment failure, etc.

  14. Casting materials

    DOE Patents [OSTI]

    Chaudhry, Anil R. (Xenia, OH); Dzugan, Robert (Cincinnati, OH); Harrington, Richard M. (Cincinnati, OH); Neece, Faurice D. (Lyndurst, OH); Singh, Nipendra P. (Pepper Pike, OH)

    2011-06-14

    A foam material comprises a liquid polymer and a liquid isocyanate which is mixed to make a solution that is poured, injected or otherwise deposited into a corresponding mold. A reaction from the mixture of the liquid polymer and liquid isocyanate inside the mold forms a thermally collapsible foam structure having a shape that corresponds to the inside surface configuration of the mold and a skin that is continuous and unbroken. Once the reaction is complete, the foam pattern is removed from the mold and may be used as a pattern in any number of conventional casting processes.

  15. Construction material

    DOE Patents [OSTI]

    Wagh, Arun S. (Orland Park, IL); Antink, Allison L. (Bolingbrook, IL)

    2008-07-22

    A structural material of a polystyrene base and the reaction product of the polystyrene base and a solid phosphate ceramic is applied as a slurry which includes one or more of a metal oxide or a metal hydroxide with a source of phosphate to produce a phosphate ceramic and a poly (acrylic acid or acrylate) or combinations or salts thereof and polystyrene or MgO applied to the polystyrene base and allowed to cure so that the dried aqueous slurry chemically bonds to the polystyrene base. A method is also disclosed of applying the slurry to the polystyrene base.

  16. Reference Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) by Carbon-RichProtonAbout Us HanfordReference Materials Reference

  17. Reference Materials

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) by Carbon-RichProtonAbout Us HanfordReference Materials

  18. Analysis of Dam Failure in the Saluda River February 8, 2005

    E-Print Network [OSTI]

    Morrow, James A.

    Analysis of Dam Failure in the Saluda River Valley February 8, 2005 Abstract We identify and model two possible failure modes for the Saluda Dam: gradual failure due to an enlarging breach and sudden catas- trophic failure due to liqui#12;cation of the dam. For the #12;rst case we de- scribe the breach

  19. Leveraging Client-Side DNS Failure Patterns to Identify Malicious Behaviors

    E-Print Network [OSTI]

    Giaccone, Paolo

    . In addition to DNS failures generated by domain-flux bots, we discover many diverse and stealthy failure generate DNS query failures, i.e., domain name queries to which the DNS server replies with an error- tal questions: (i) what can we learn from the DNS failures generated by a client machine? (ii) what

  20. Failure Modes of Vacuum Plasma Spray Tungsten Coating Created on Carbon Fibre Composites under Thermal Loads

    E-Print Network [OSTI]

    Failure Modes of Vacuum Plasma Spray Tungsten Coating Created on Carbon Fibre Composites under Thermal Loads

  1. Photovoltaic Materials

    SciTech Connect (OSTI)

    Duty, C.; Angelini, J.; Armstrong, B.; Bennett, C.; Evans, B.; Jellison, G. E.; Joshi, P.; List, F.; Paranthaman, P.; Parish, C.; Wereszczak, A.

    2012-10-15

    The goal of the current project was to help make the US solar industry a world leader in the manufacture of thin film photovoltaics. The overall approach was to leverage ORNL’s unique characterization and processing technologies to gain a better understanding of the fundamental challenges for solar cell processing and apply that knowledge to targeted projects with industry members. ORNL has the capabilities in place and the expertise required to understand how basic material properties including defects, impurities, and grain boundaries affect the solar cell performance. ORNL also has unique processing capabilities to optimize the manufacturing process for fabrication of high efficiency and low cost solar cells. ORNL recently established the Center for Advanced Thin-film Systems (CATS), which contains a suite of optical and electrical characterization equipment specifically focused on solar cell research. Under this project, ORNL made these facilities available to industrial partners who were interested in pursuing collaborative research toward the improvement of their product or manufacturing process. Four specific projects were pursued with industrial partners: Global Solar Energy is a solar industry leader in full scale production manufacturing highly-efficient Copper Indium Gallium diSelenide (CIGS) thin film solar material, cells and products. ORNL worked with GSE to develop a scalable, non-vacuum, solution technique to deposit amorphous or nanocrystalline conducting barrier layers on untextured stainless steel substrates for fabricating high efficiency flexible CIGS PV. Ferro Corporation’s Electronic, Color and Glass Materials (“ECGM”) business unit is currently the world’s largest supplier of metallic contact materials in the crystalline solar cell marketplace. Ferro’s ECGM business unit has been the world's leading supplier of thick film metal pastes to the crystalline silicon PV industry for more than 30 years, and has had operational cells and modules in the field for 25 years. Under this project, Ferro leveraged world leading analytical capabilities at ORNL to characterize the paste-to-silicon interface microstructure and develop high efficiency next generation contact pastes. Ampulse Corporation is developing a revolutionary crystalline-silicon (c-Si) thin-film solar photovoltaic (PV) technology. Utilizing uniquely-textured substrates and buffer materials from the Oak Ridge National Laboratory (ORNL), and breakthroughs in Hot-Wire Chemical Vapor Deposition (HW-CVD) techniques in epitaxial silicon developed at the National Renewable Energy Laboratory (NREL), Ampulse is creating a solar technology that is tunable in silicon thickness, and hence in efficiency and economics, to meet the specific requirements of multiple solar PV applications. This project focused on the development of a high rate deposition process to deposit Si, Ge, and Si1-xGex films as an alternate to hot-wire CVD. Mossey Creek Solar is a start-up company with great expertise in the solar field. The primary interest is to create and preserve jobs in the solar sector by developing high-yield, low-cost, high-efficiency solar cells using MSC-patented and -proprietary technologies. The specific goal of this project was to produce large grain formation in thin, net-shape-thickness mc-Si wafers processed with high-purity silicon powder and ORNL's plasma arc lamp melting without introducing impurities that compromise absorption coefficient and carrier lifetime. As part of this project, ORNL also added specific pieces of equipment to enhance our ability to provide unique insight for the solar industry. These capabilities include a moisture barrier measurement system, a combined physical vapor deposition and sputtering system dedicated to cadmium-containing deposits, adeep level transient spectroscopy system useful for identifying defects, an integrating sphere photoluminescence system, and a high-speed ink jet printing system. These tools were combined with others to study the effect of defects on the performance of crystalline silicon and

  2. Statistical analysis of cascading failures in power grids

    SciTech Connect (OSTI)

    Chertkov, Michael; Pfitzner, Rene; Turitsyn, Konstantin

    2010-12-01

    We introduce a new microscopic model of cascading failures in transmission power grids. This model accounts for automatic response of the grid to load fluctuations that take place on the scale of minutes, when optimum power flow adjustments and load shedding controls are unavailable. We describe extreme events, caused by load fluctuations, which cause cascading failures of loads, generators and lines. Our model is quasi-static in the causal, discrete time and sequential resolution of individual failures. The model, in its simplest realization based on the Directed Current description of the power flow problem, is tested on three standard IEEE systems consisting of 30, 39 and 118 buses. Our statistical analysis suggests a straightforward classification of cascading and islanding phases in terms of the ratios between average number of removed loads, generators and links. The analysis also demonstrates sensitivity to variations in line capacities. Future research challenges in modeling and control of cascading outages over real-world power networks are discussed.

  3. Failure modes and effects analysis of fusion magnet systems

    SciTech Connect (OSTI)

    Zimmermann, M; Kazimi, M S; Siu, N O; Thome, R J

    1988-12-01

    A failure modes and consequence analysis of fusion magnet system is an important contributor towards enhancing the design by improving the reliability and reducing the risk associated with the operation of magnet systems. In the first part of this study, a failure mode analysis of a superconducting magnet system is performed. Building on the functional breakdown and the fault tree analysis of the Toroidal Field (TF) coils of the Next European Torus (NET), several subsystem levels are added and an overview of potential sources of failures in a magnet system is provided. The failure analysis is extended to the Poloidal Field (PF) magnet system. Furthermore, an extensive analysis of interactions within the fusion device caused by the operation of the PF magnets is presented in the form of an Interaction Matrix. A number of these interactions may have significant consequences for the TF magnet system particularly interactions triggered by electrical failures in the PF magnet system. In the second part of this study, two basic categories of electrical failures in the PF magnet system are examined: short circuits between the terminals of external PF coils, and faults with a constant voltage applied at external PF coil terminals. An electromagnetic model of the Compact Ignition Tokamak (CIT) is used to examine the mechanical load conditions for the PF and the TF coils resulting from these fault scenarios. It is found that shorts do not pose large threats to the PF coils. Also, the type of plasma disruption has little impact on the net forces on the PF and the TF coils. 39 refs., 30 figs., 12 tabs.

  4. Materials Science & Engineering

    E-Print Network [OSTI]

    Materials Science & Engineering The development of new high-performance materials for energy Use of Advanced Characterization Techniques for Materials Development in Energy and Transportation and composition of materials at higher spatial resolution, with greater efficiency, and on real materials

  5. Critical Materials Institute

    ScienceCinema (OSTI)

    Alex King

    2013-06-05

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

  6. Ground control failures. A pictorial view of case studies

    SciTech Connect (OSTI)

    Peng, S.S.

    2007-07-01

    The book shows, in pictorial views, many forms and/or stages of types of failures in mines, for instance, cutter, roof falls, and cribs. In each case, the year of occurrence is stated in the beginning so that the environment or technological background under which it occurred are reflected. The narrative than begins with the mining and geological conditions, followed by a description of the ground control problems and recommended solutions and results, if any. The sections cover failure of pillars, roof falls, longwall, roof bolting, multiple-seam mining, floor heave, longwall, flooding and weathering of coal, old workings, and shortwall and thin-seam plow longwall.

  7. Selective Recovery From Failures In A Task Parallel Programming Model

    SciTech Connect (OSTI)

    Dinan, James S.; Singri, Arjun; Sadayappan, Ponnuswamy; Krishnamoorthy, Sriram

    2010-05-17

    We present a fault tolerant task pool execution environment that is capable of performing fine-grain selective restart using a lightweight, distributed task completion tracking mechanism. Compared with conventional checkpoint/restart techniques, this system offers a recovery penalty that is proportional to the degree of failure rather than the system size. We evaluate this system using the Self Consistent Field (SCF) kernel which forms an important component in ab initio methods for computational chemistry. Experimental results indicate that fault tolerant task pools are robust in the presence of an arbitrary number of failures and that they offer low overhead in the absence of faults.

  8. Aspirin and Statin Nonuse Associated With Early Biochemical Failure After Prostate Radiation Therapy

    SciTech Connect (OSTI)

    Zaorsky, Nicholas G.; Buyyounouski, Mark K.; Li, Tianyu; Horwitz, Eric M.

    2012-09-01

    Purpose: To present the largest retrospective series investigating the effect of aspirin and statins, which are hypothesized to have antineoplastic properties, on biochemical failure (nadir plus 2 ng/mL) after prostate radiation therapy (RT). Methods and Materials: Between 1989 and 2006, 2051 men with clinically localized prostate cancer received definitive RT alone (median dose, 76 Gy). The rates of aspirin use and statin use (defined as any use at the time of RT or during follow-up) were 36% and 34%, respectively. The primary endpoint of the study was an interval to biochemical failure (IBF) of less than 18 months, which has been shown to be the single strongest predictor of distant metastasis, prostate cancer survival, and overall survival after RT. Patient demographic characteristics and tumor staging factors were assessed with regard to associations with the endpoint. Univariate analysis was performed with the {chi}{sup 2} test for categorical variables and the Wilcoxon test for continuous variables. Multivariable analysis was performed with a multiple logistic regression. Results: The median follow-up was 75 months. Univariate analysis showed that an IBF of less than 18 months was associated with aspirin nonuse (P<.0001), statin nonuse (P<.0001), anticoagulant nonuse (P=.0006), cardiovascular disease (P=.0008), and prostate-specific antigen (continuous) (P=.008) but not with Gleason score, age, RT dose, or T stage. On multivariate analysis, only aspirin nonuse (P=.0012; odds ratio, 2.052 [95% confidence interval, 1.328-3.172]) and statin nonuse (P=.0002; odds ratio, 2.465 [95% confidence interval, 1.529-3.974]) were associated with an IBF of less than 18 months. Conclusions: In patients who received RT for prostate cancer, aspirin or statin nonuse was associated with early biochemical failure, a harbinger of distant metastasis and death. Further study is needed to confirm these findings and to determine the optimal dosing and schedule, as well as the relative benefits and risks, of both therapies in combination with RT.

  9. HAZARDOUS MATERIALS INCIDENTS What are hazardous materials?

    E-Print Network [OSTI]

    Fernandez, Eduardo

    HAZARDOUS MATERIALS INCIDENTS What are hazardous materials? Hazardous materials are chemicals, accidentally spilled, or released. In addition to laboratory chemicals, hazardous materials may include common not involve highly toxic or noxious hazardous materials, a fire, or an injury requiring medical attention

  10. HAZARDOUS MATERIALS INCIDENTS What are hazardous materials?

    E-Print Network [OSTI]

    Fernandez, Eduardo

    HAZARDOUS MATERIALS INCIDENTS What are hazardous materials? Hazardous materials are chemicals I do if there is a small spill in the area and personnel trained in Hazardous Material clean up, or there is a small spill where personnel trained in Hazardous Material clean up or an appropriate spill kit

  11. HAZARDOUS MATERIALS INCIDENTS What are hazardous materials?

    E-Print Network [OSTI]

    Fernandez, Eduardo

    HAZARDOUS MATERIALS INCIDENTS What are hazardous materials? Hazardous materials are chemicals I do if there is a small spill in the area and personnel trained in Hazardous Material clean up spill where personnel trained in Hazardous Material clean up or an appropriate spill kit

  12. HAZARDOUS MATERIALS INCIDENTS What are hazardous materials?

    E-Print Network [OSTI]

    Fernandez, Eduardo

    HAZARDOUS MATERIALS INCIDENTS What are hazardous materials? Hazardous materials are chemicals I do if there is a small spill in the area and personnel trained in Hazardous Material clean up personnel trained in Hazardous Material clean up or an appropriate spill kit is not available? Call 561

  13. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2014-11-25

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  14. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  15. LESSONS LEARNED FROM AN IMPOUNDMENT SLOPE FAILURE INVOLVING GEOSYNTHETICS

    E-Print Network [OSTI]

    underwent final closure construction in the summer of 1994. The landfill previously accepted an average for the sedimentation pond and the landfill closure was completed by 31 December 1994. The GCL used at this site, Shearbox test, Failure, Landfill, Sedimentation pond AUTHORS: Kyle E. Nay, Environmental Specialist, Ohio

  16. Composting Successes and Failures Extending the Growing Season Workshop

    E-Print Network [OSTI]

    Amin, S. Massoud

    3/18/2014 1 Composting Successes and Failures Extending the Growing Season Workshop LaMoine Nickel University of MN SWROC March 12, 2014 Beginning of compost process 9/6/2013 Finished compost product 11/19/2013 What is Composting Composting is a biological process in which microorganisms convert organic

  17. FAILURE BEHAVIOR IDENTIFICATION FOR A SPACE ANTENNA VIA NEURAL NETWORKS

    E-Print Network [OSTI]

    Antsaklis, Panos

    FAILURE BEHAVIOR IDENTIFICATION FOR A SPACE ANTENNA VIA NEURAL NETWORKS Michcl A. Sartoi David Taylo Research Center Code 1941 BeteA Mayln 200845000 ABSTRACT Using neural networks, a method-layer perceptron, the second uses a multi-layer perceptron and neural networks trained with the quadratic

  18. Learning From NASA Mishaps: What Separates Success From Failure?

    E-Print Network [OSTI]

    Rhoads, James

    1 Learning From NASA Mishaps: What Separates Success From Failure? Project Management Challenge Call? NASA Mishap. An unplanned event that results in at least one of the following: ­ Injury to non-NASA personnel, caused by NASA operations. ­ Damage to public or private property (including foreign property

  19. MEMS Reliability: Infrastructure, Test Structures, Experiments, and Failure Modes

    SciTech Connect (OSTI)

    TANNER,DANELLE M.; SMITH,NORMAN F.; IRWIN,LLOYD W.; EATON,WILLIAM P.; HELGESEN,KAREN SUE; CLEMENT,J. JOSEPH; MILLER,WILLIAM M.; MILLER,SAMUEL L.; DUGGER,MICHAEL T.; WALRAVEN,JEREMY A.; PETERSON,KENNETH A.

    2000-01-01

    The burgeoning new technology of Micro-Electro-Mechanical Systems (MEMS) shows great promise in the weapons arena. We can now conceive of micro-gyros, micro-surety systems, and micro-navigators that are extremely small and inexpensive. Do we want to use this new technology in critical applications such as nuclear weapons? This question drove us to understand the reliability and failure mechanisms of silicon surface-micromachined MEMS. Development of a testing infrastructure was a crucial step to perform reliability experiments on MEMS devices and will be reported here. In addition, reliability test structures have been designed and characterized. Many experiments were performed to investigate failure modes and specifically those in different environments (humidity, temperature, shock, vibration, and storage). A predictive reliability model for wear of rubbing surfaces in microengines was developed. The root causes of failure for operating and non-operating MEMS are discussed. The major failure mechanism for operating MEMS was wear of the polysilicon rubbing surfaces. Reliability design rules for future MEMS devices are established.

  20. FAILURE OF GPS FUNCTIONING CAUSED BY EXTREME SOLAR RADIO EVENTS

    E-Print Network [OSTI]

    solar radio emission followed the flare exceeded power solar radio bursts (SRB) in all flares known tillFAILURE OF GPS FUNCTIONING CAUSED BY EXTREME SOLAR RADIO EVENTS E. L. Afraimovich1 , V. V. Demyanov1 , D. E. Gary2 , A. B. Ishin1 , and G. Ya. Smolkov1 1) Institute of Solar-Terrestrial Physics

  1. An Instability Leading to Failure of Polyethylene in Uniaxial Creep

    E-Print Network [OSTI]

    An Instability Leading to Failure of Polyethylene in Uniaxial Creep L. J. ZAPAS and J. M. CRISSMAN model, a point of instability is pre- dicted for the uniaxial creep of high density polyethylene. From dead load experiments it has been found that the instabil- ity occurs for linear -polyethylene

  2. Backup strategy for robots' failures in an automotive assembly system

    E-Print Network [OSTI]

    Ben-Gal, Irad E.

    history: Received 23 October 2006 Accepted 16 September 2007 Keywords: Automotive industry Assembly lines in the automotive industry High-volume body-shop systems in the automotive industry often consist of a seriesBackup strategy for robots' failures in an automotive assembly system Tomer Kahan a , Yossi Bukchin

  3. Failure Modes and Effects Analysis -LRRR PAGE ~1 Ofll 8

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Analysis (FMEA) is to discover critical failure areas in a system and to remove susceptibility. This memo contains the results of a preliminary FMEA for the LRRR experiment. This analysis will be revised deployed on the moon as a part of the Apollo 11 mission, this FMEA will not dwell on the aspects

  4. COPYRIGHT NOTICE: James Bessen & Michael J. Meurer: Patent Failure

    E-Print Network [OSTI]

    Landweber, Laura

    COPYRIGHT NOTICE: James Bessen & Michael J. Meurer: Patent Failure is published by Princeton is the United States; the property is U.S. Patent No. 4,528,643, granted in 1985; the owner who initiated ure of patent-related institutions and patent law generally to get the details right.This widespread

  5. Energy-Efficient Neuronal Computation via Quantal Synaptic Failures

    E-Print Network [OSTI]

    Levy, William B.

    Energy-Efficient Neuronal Computation via Quantal Synaptic Failures William B Levy1 and Robert A, and many of these com- promises can be expressed in terms of energy efficiency. For example, a compromise; efficiency; energy; entropy; infor- mation theory; mutual information; optimization; quantal fail- ures

  6. Predicting Global Failure Regimes in Complex Information Systems

    E-Print Network [OSTI]

    Predicting Global Failure Regimes in Complex Information Systems June 19, 2012 NetONets 2012 Chris­ with application to complex information systems, e.g., Internet, Clouds, Grids What is the problem? Why is it hard; Ongoing & Planned ITL Research: How can we help to increase the reliability of complex information systems

  7. Predicting Global Failure Regimes in Complex Information Systems

    E-Print Network [OSTI]

    Predicting Global Failure Regimes in Complex Information Systems DoE COMBINE Workshop September 19 & Ongoing Research­ with application to complex information systems, e.g., Internet, Clouds, Grids What & Planned ITL Research: How can we help to increase the reliability of complex information systems

  8. Predicting Electricity Distribution Feeder Failures Using Machine Learning Susceptibility Analysis

    E-Print Network [OSTI]

    Cortes, Corinna

    Predicting Electricity Distribution Feeder Failures Using Machine Learning Susceptibility Analysis}@coned.com Abstract A Machine Learning (ML) System known as ROAMS (Ranker for Open-Auto Maintenance Scheduling feeder cables that supply electricity to the boroughs of New York City. In Manhattan, rankings

  9. Understanding Consistency Maintenance in Service Discovery Architectures during Communication Failure

    E-Print Network [OSTI]

    Mills, Kevin

    themselves into larger collections that cooperate to meet an application need, and (4) to detect and adapt to failures. 3-Party Design 2-Party Design Adaptive 2/3-Party Design Vertically Integrated 3-Party Design>> Announce Service Processing() > start Renewal Task() ServiceManager() > start Service

  10. Fast Simulation, Monitoring, and Mitigation of Cascading Failure

    E-Print Network [OSTI]

    blackout. Large cascading failures are not frequent, but they have substantial risk due to their large societal costs. The August 2003 cascading blackout of portions of the northeastern U.S. and eastern Canada had direct costs of the order of $6-$10 billion. Large blackouts can also have significant indirect

  11. Mitigating Cascading Failures in Interdependent Power Grids and Communication Networks

    E-Print Network [OSTI]

    Hay, David

    -time monitoring and rapid control decisions for mitigating failures led to a catastrophic blackout which affected 50 million people in Northeast Amer- ica. According to the final report of the 2003 blackout [6 than 5 minutes and led to a full blackout in the Northeast United States and parts of Canada

  12. Geological and mathematical framework for failure modes in granular rock

    E-Print Network [OSTI]

    Borja, Ronaldo I.

    Geological and mathematical framework for failure modes in granular rock Atilla Aydina, *, Ronaldo I. Borjab , Peter Eichhubla,1 a Department of Geological and Environmental Sciences, Stanford processes in granular rock and provide a geological framework for the corresponding structures. We describe

  13. Heading Off Correlated Failures through Independence-as-a-Service

    E-Print Network [OSTI]

    Haller, Gary L.

    Heading Off Correlated Failures through Independence-as-a-Service Ennan Zhai1 Ruichuan Chen2, David Losses Data Center Outages Generate Big Losses Downtime in a data center can cost an average of $505 Operational Trends Report #12;Service Outage Losses Data Center Outages Generate Big Losses Downtime in a data

  14. Special Issue Article Post-failure recovery of MPI

    E-Print Network [OSTI]

    Dongarra, Jack

    -tolerance techniques have the potential to prevent full-scale application restart and therefore lower the cost incurred-level failure mitigation 1. Introduction Innovation in science and engineering strongly depends on the pervasive unrivaled per- formance. The rationale behind this development is, essen- tially, driven by the lower

  15. Materials Science & Tech Division | Advanced Materials | ORNL

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

    applied materials science and technology. One key component of the division is a strong Basic Energy Sciences (BES) portfolio that pushes the frontiers of materials theory,...

  16. Results of industry experience survey on coiled tubing uses and failures

    SciTech Connect (OSTI)

    Maldonado, J.G.; Cayard, M.S.; Kane, R.D.

    1999-11-01

    A survey of coiled tubing failures in various field applications was conducted. The survey included the collection of information on failure type, number of strain cycles to failure, service environment, well depth, failure location on the coiled tubing string, and coiled tubing grade employed. The most prevalent causes of failures and the impact of localized corrosion on the performance of coiled tubing were assessed from over thirty case studies herein reported. Pitting and tensile overload were the primary causes for failure in fifty percent of the cases reported from the field. Fatigue and weld area failures were the next most common types of failure. Most failures occurred within the range of 10 to 50 strain cycles. H{sub 2}S and brine/water containing environments were the most prevalent service conditions. Most failures occurred at well depths between 5,001 to 10,000 feet (1,524.3 to 3,048 meters). Also, most failures occurred in the coiled tubing string near the surface (less than 1,000 feet (304.8 meters)). Failures in roughly similar numbers were reported in 70, 80 and 100 coiled tubing grades. The understanding of the principal modes of failure herein reported should help in the development of improved handling and running procedures to minimize coiled tubing failures.

  17. Advanced Materials Manufacturing | ORNL

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

    Advanced Materials Manufacturing New materials drive the development of innovative products. Building upon a rich history in materials science, ORNL is discovering and developing...

  18. Materials Project: A Materials Genome Approach

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Ceder, Gerbrand [MIT; Persson, Kristin [LBNL

    Technological innovation - faster computers, more efficient solar cells, more compact energy storage - is often enabled by materials advances. Yet, it takes an average of 18 years to move new materials discoveries from lab to market. This is largely because materials designers operate with very little information and must painstakingly tweak new materials in the lab. Computational materials science is now powerful enough that it can predict many properties of materials before those materials are ever synthesized in the lab. By scaling materials computations over supercomputing clusters, this project has computed some properties of over 80,000 materials and screened 25,000 of these for Li-ion batteries. The computations predicted several new battery materials which were made and tested in the lab and are now being patented. By computing properties of all known materials, the Materials Project aims to remove guesswork from materials design in a variety of applications. Experimental research can be targeted to the most promising compounds from computational data sets. Researchers will be able to data-mine scientific trends in materials properties. By providing materials researchers with the information they need to design better, the Materials Project aims to accelerate innovation in materials research.[copied from http://materialsproject.org/about] You will be asked to register to be granted free, full access.

  19. Mechanism of fatigue in micron-scale films of polycrystalline silicon for microelectromechanical applications

    SciTech Connect (OSTI)

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

    2001-08-02

    Reported nearly a decade ago, cyclic fatigue failure in silicon thin films has remained a mystery. Silicon does not display the room temperature plasticity or extrinsic toughening mechanisms necessary to cause fatigue in either ductile (e.g., metals) or brittle (e.g., ceramics and ordered mintermetallic) materials.

  20. Full-Scale Tests of Butt-Welded Splices in Heavy-Rolled Steel Sections Subjected to Primary Tensile Stresses

    E-Print Network [OSTI]

    Bruneau, Michel

    of the observed failure. The splice with full penetration welds exhibited satisfactory strength and ductility are to be performed. Several cases of partial or complete brittle fracture have been reported during fabrication toughness of the base material at the failed joint. The weld design and process used resulted in an initial

  1. International Journal of Fracture 119/120: 487499, 2003. 2003 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    Volinsky, Alex A.

    International Journal of Fracture 119/120: 487­499, 2003. © 2003 Kluwer Academic Publishers. Printed in the Netherlands. Mechanical properties and fracture toughness of organo-silicate glass (OSG-porosity is discussed. Failure modes include poor mechanical strength, low material stiffness, and brittle fracture due

  2. Development and deployment of constitutive softening routines in Eulerian hydrocodes.

    SciTech Connect (OSTI)

    Fuller, Timothy Jesse; Dewers, Thomas A.; Swan, Matthew Scot

    2013-03-01

    The state of the art in failure modeling enables assessment of crack nucleation, propagation, and progression to fragmentation due to high velocity impact. Vulnerability assessments suggest a need to track material behavior through failure, to the point of fragmentation and beyond. This eld of research is particularly challenging for structures made of porous quasi-brittle materials, such as ceramics used in modern armor systems, due to the complex material response when loading exceeds the quasi-brittle material's elastic limit. Further complications arise when incorporating the quasi-brittle material response in multi-material Eulerian hydrocode simulations. In this report, recent e orts in coupling a ceramic materials response in the post-failure regime with an Eulerian hydro code are described. Material behavior is modeled by the Kayenta material model [2]and Alegra as the host nite element code [14]. Kayenta, a three invariant phenomenological plasticity model originally developed for modeling the stress response of geologic materials, has in recent years been used with some success in the modeling of ceramic and other quasi-brittle materials to high velocity impact. Due to the granular nature of ceramic materials, Kayenta allows for signi cant pressures to develop due to dilatant plastic ow, even in shear dominated loading where traditional equations of state predict little or no pressure response. When a material's ability to carry further load is compromised, Kayenta allows the material's strength and sti ness to progressively degrade through the evolution of damage to the point of material failure. As material dilatation and damage progress, accommodations are made within Alegra to treat in a consistent manner the evolving state.

  3. Advanced Materials | ORNL

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

    Specific Binding ORNL discovery holds potential for separations, sensors, batteries, biotech and more Home | Science & Discovery | Advanced Materials Advanced Materials |...

  4. Composite material dosimeters

    DOE Patents [OSTI]

    Miller, Steven D. (Richland, WA)

    1996-01-01

    The present invention is a composite material containing a mix of dosimeter material powder and a polymer powder wherein the polymer is transparent to the photon emission of the dosimeter material powder. By mixing dosimeter material powder with polymer powder, less dosimeter material is needed compared to a monolithic dosimeter material chip. Interrogation is done with excitation by visible light.

  5. Method for recycling tires and similarly compounded materials to recover usable constituents

    SciTech Connect (OSTI)

    Letsch, W.

    1980-12-23

    A processing plant and method are described for processing scrap tires and similar materials containing a mixture of technical rubber, scrap metal and tire cord in which the plant is essentially vehicular and thus eliminates the necessity of hauling accumulated tires long distances with the accompanying costs. The plant includes means for directing mixed tire sizes to a cyrogenic section where the technical rubber is reduced to a sufficient temperature making it brittle so that initial separation of reusable technical rubber is accomplished; the plant is operated essentially on the reusable by-products of pyrolytic reduction of the tires so that hydrocarbons and heated gas are utilized and additional commercial by-products such as commercial soots, metal and tire beads are obtained.

  6. Impact of intrinsic localized modes of atomic motion on materials properties

    SciTech Connect (OSTI)

    Manley, M E

    2010-01-20

    Recent neutron and x-ray scattering measurements show intrinsic localized modes (ILMs) in metallic uranium and ionic sodium iodide. Here, the role ILMs play in the behavior of these materials is examined. With the thermal activation of ILMs, thermal expansion is enhanced, made more anisotropic, and, at a microscopic level, becomes inhomogeneous. Interstitial diffusion, ionic conductivity, the annealing rate of radiation damage, and void growth are all influenced by ILMs. The lattice thermal conductivity is suppressed above the ILM activation temperature while no impact is observed in the electrical conductivity. This complement of transport properties suggests that ILMs could improve thermoelectric performance. Ramifications also include thermal ratcheting, a transition from brittle to ductile fracture, and possibly a phase transformation in uranium.

  7. Relational Neural Evolution Approach to Bank Failure Prediction

    SciTech Connect (OSTI)

    Abudu, Bolanle; Markose, Sheri [Centre for Computational Finance and Economic Agents, University of Essex, Essex, C04 3SQ (United Kingdom)

    2007-12-26

    Relational neural networks as a concept offers a unique opportunity for improving classification accuracy by exploiting relational structure in data. The premise is that a relational classification technique, which uses information implicit in relationships, should classify more accurately than techniques that only examine objects in isolation. In this paper, we study the use of relational neural networks for predicting bank failure. Alongside classical financial ratios normally used as predictor variables, we introduced new relational variables for the network. The relational neural network structure, specified as a combination of feed forward and recurrent neural networks, is determined by bank data through neuro-evolution. We discuss empirical results comparing performance of the relational approach to standard propositional methods used for bank failure prediction.

  8. Bayesian failure probability model sensitivity study. Final report

    SciTech Connect (OSTI)

    Not Available

    1986-05-30

    The Office of the Manager, National Communications System (OMNCS) has developed a system-level approach for estimating the effects of High-Altitude Electromagnetic Pulse (HEMP) on the connectivity of telecommunications networks. This approach incorporates a Bayesian statistical model which estimates the HEMP-induced failure probabilities of telecommunications switches and transmission facilities. The purpose of this analysis is to address the sensitivity of the Bayesian model. This is done by systematically varying two model input parameters--the number of observations, and the equipment failure rates. Throughout the study, a non-informative prior distribution is used. The sensitivity of the Bayesian model to the noninformative prior distribution is investigated from a theoretical mathematical perspective.

  9. Analysis of major failures in Europe's power grid

    E-Print Network [OSTI]

    Rosas-Casals, Martí

    2009-01-01

    Power grids are prone to failure. Time series of reliability measures such as total power loss or energy not supplied can give significant account of the underlying dynamical behavior of these systems, specially when the resulting probability distributions present remarkable features such as an algebraic tail, for example. In this paper, seven years (from 2002 to 2008) of Europe's transport of electricity network failure events have been analyzed and the best fit for this empirical data probability distribution is presented. With the actual span of available data and although there exists a moderate support for the power law model, the relatively small amount of events contained in the function's tail suggests that other causal factors might be significantly ruling the system's dynamics.

  10. A network approach for power grid robustness against cascading failures

    E-Print Network [OSTI]

    Wang, Xiangrong; Kooij, Robert E; Van Mieghem, Piet

    2015-01-01

    Cascading failures are one of the main reasons for blackouts in electrical power grids. Stable power supply requires a robust design of the power grid topology. Currently, the impact of the grid structure on the grid robustness is mainly assessed by purely topological metrics, that fail to capture the fundamental properties of the electrical power grids such as power flow allocation according to Kirchhoff's laws. This paper deploys the effective graph resistance as a metric to relate the topology of a grid to its robustness against cascading failures. Specifically, the effective graph resistance is deployed as a metric for network expansions (by means of transmission line additions) of an existing power grid. Four strategies based on network properties are investigated to optimize the effective graph resistance, accordingly to improve the robustness, of a given power grid at a low computational complexity. Experimental results suggest the existence of Braess's paradox in power grids: bringing an additional li...

  11. Method for forming materials

    DOE Patents [OSTI]

    Tolle, Charles R. (Idaho Falls, ID); Clark, Denis E. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); Miller, Karen S. (Idaho Falls, ID)

    2009-10-06

    A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

  12. Statistical Analysis of LifeData with Masked CauseofFailure

    E-Print Network [OSTI]

    Basu, Sanjib

    , a detailed Failure Mode Effect Analysis (FMEA) can be carried out in a routine manner. In reliability been pursued under the general heading of Failure Mode Effect Analysis (FMEA) when the exact causes

  13. PID Failure of c-Si and Thin-Film Modules and Possible Correlation...

    Energy Savers [EERE]

    PID Failure of c-Si and Thin-Film Modules and Possible Correlation with Leakage Currents PID Failure of c-Si and Thin-Film Modules and Possible Correlation with Leakage Currents...

  14. New Functional Imaging Technology to Differentiate between Chronic Obstructive Pulmonary Disease and Heart Failure

    E-Print Network [OSTI]

    Pollack, Charles V.; Slattery, David E

    2011-01-01

    improvement of congestive heart failure: a pilot study. BMCtesting and the accuracy of heart failure diagnosis in theemergency department. Circ Heart Fail. 2010 Jan;3(1):104-10.

  15. Relaxin: Review of Biology and Potential Role in Treating Heart Failure

    E-Print Network [OSTI]

    Teichman, Sam L.; Unemori, Elaine; Teerlink, John R.; Cotter, Gad; Metra, Marco

    2010-01-01

    Curr Heart Fail Rep (2010) 7:75–82 DOI 10.1007/s11897-010-Potential Role in Treating Heart Failure Sam L. Teichman &of patients with acute heart failure. Preliminary results

  16. Reliability and construct validity of PROMIS® measures for patients with heart failure who undergo heart transplant

    E-Print Network [OSTI]

    2015-01-01

    a community- based sample of heart failure patients. JournalQuality of life in patients with advanced heart failure.Journal of Heart and Lung Transplantation, 11(2 Pt 1), 273–

  17. Reversing Heart Failure: Diastolic Recoil in a Proposed Cardiac Support Device 

    E-Print Network [OSTI]

    Snowden, Timothy D

    2012-07-11

    Congestive heart failure (CHF) holds millions in the grip of an endless cycle of decreased cardiac output and degenerative remodeling, often with little hope of recovery. Diastolic dysfunction, or failure of the heart to properly fill, is a...

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

    SciTech Connect (OSTI)

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

    1981-01-01

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

  19. Failure and Degradation Modes of PV Modules in a Hot Dry Climate...

    Office of Environmental Management (EM)

    Failure and Degradation Modes of PV Modules in a Hot Dry Climate: Results After 12 to 26 Years of Field Exposure Failure and Degradation Modes of PV Modules in a Hot Dry Climate:...

  20. Defining Human Failure Events for Petroleum Risk Analysis

    SciTech Connect (OSTI)

    Ronald L. Boring; Knut Øien

    2014-06-01

    In this paper, an identification and description of barriers and human failure events (HFEs) for human reliability analysis (HRA) is performed. The barriers, called target systems, are identified from risk significant accident scenarios represented as defined situations of hazard and accident (DSHAs). This report serves as the foundation for further work to develop petroleum HFEs compatible with the SPAR-H method and intended for reuse in future HRAs.

  1. Statistical Modeling of Corrosion Failures in Natural Gas Transmission Pipelines 

    E-Print Network [OSTI]

    Cobanoglu, Mustafa Murat

    2014-03-28

    such as pipeline and operator information, failure causes, consequences of these incidents, cathodic protection conditions, coating conditions, property damage, year of installation information, and etc. However, a number of items are missing. For example... was external corrosion due to inadequate cathodic protection (Riemer and Orazem, 2000). Due to an increasing number of incidents and their consequences, reliability of the pipeline system is becoming crucial for the operators and public in general. Public...

  2. Prioritizing Water Pipe Replacement and Rehabilitation by Evaluating Failure Risk 

    E-Print Network [OSTI]

    Lee, Sang Hyun

    2012-02-14

    .1 Problem Statement Damage to water pipes is influenced by various factors, including design, construction, and management. Grey cast iron pipes without any coating or lining in or outside and unlined ductile iron pipes (DIPs) are under the direct... ......................................................................................... 5 2.2 Methods to Access Failure Risk of Water Pipes................................. 6 2.2.1 Deterioration Point Assignment (DPA) Method ....................... 6 2.2.2 Break-even Analysis...

  3. Potential failure of steam generator tubes following a station blackout

    SciTech Connect (OSTI)

    Ward, L.W.; Palmrose, D.E.

    1994-12-31

    The U.S. Nuclear Regulatory Commission is considering changes to pressurized water reactor (PWR) requirements relating to steam generator tube plugging and repair criteria, including leakage monitoring. The proposed changes are known as the alternate tube plugging criteria (APC) and are intended to permit PWRs to operate with through-wall cracks in steam generator tubes subject to meeting a specified limit on predicted primary to secondary leakage under accident conditions. To assess the consequences of the alternate plugging criteria, analyses were performed for a station blackout sequence in which the reactor core melts while the reactor coolant system (RCS) remains at high pressure. Evaluations were conducted to investigate the potential for tube failure with and without secondary system depressurization. The excessive heat coupled with the high-pressure differentials across the steam generator tubes could result in creep rupture failure of the tubes during a severe accident, which could lead to a radiological release directly to the environment. In order to assess the safety significance of the APC, it is important to identify the level of steam generator tube leakage that can occur without challenging the previous study conclusions that steam generator creep failure will not occur prior to a surge line or hot-leg failure. To assess the effect of leakage on steam generator tube integrity during a core melt sequence with the RCS at high pressure and the secondary side of the steam generators pressurized and depressurized, an analysis was performed for a core melt event resulting from an unmitigated station blackout to identify the total steamenerator and tube leakage flow rates that could induce tube ruptures prior to other RCS boudary faliures that could depressurize the RCS.

  4. Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs

    SciTech Connect (OSTI)

    Khaleel, Mohammad A.; Simonen, Fredric A.

    2009-05-01

    The work described in this report applies probabilistic structural mechanics models to predict the reliability of nuclear pressure boundary components. These same models are then applied to evaluate the effectiveness of alternative programs for inservice inspection to reduce these failure probabilities. Results of the calculations support the development and implementation of risk-informed inservice inspection of piping and vessels. Studies have specifically addressed the potential benefits of ultrasonic inspections to reduce failure probabilities associated with fatigue crack growth and stress-corrosion cracking. Parametric calculations were performed with the computer code pc-PRAISE to generate an extensive set of plots to cover a wide range of pipe wall thicknesses, cyclic operating stresses, and inspection strategies. The studies have also addressed critical inputs to fracture mechanics calculations such as the parameters that characterize the number and sizes of fabrication flaws in piping welds. Other calculations quantify uncertainties associated with the inputs calculations, the uncertainties in the fracture mechanics models, and the uncertainties in the resulting calculated failure probabilities. A final set of calculations address the effects of flaw sizing errors on the effectiveness of inservice inspection programs.

  5. LX-17 Corner-Turning and Reactive Flow Failure

    SciTech Connect (OSTI)

    Souers, P C; Andreski, H; Cook III, C F; Garza, R; Pastrone, R; Phillips, D; Roeske, F; Vitello, P; Molitoris, J

    2004-03-11

    We have performed a series of highly-instrumented experiments examining corner-turning of detonation. A TATB booster is inset 15 mm into LX-17 (92.5% TATB, 7.5% kel-F) so that the detonation must turn a right angle around an air well. An optical pin located at the edge of the TATB gives the start time of the corner-turn. The breakout time on the side and back edges is measured with streak cameras. Three high-resolution X-ray images were taken on each experiment to examine the details of the detonation. We have concluded that the detonation cannot turn the corner and subsequently fails, but the shock wave continues to propagate in the unreacted explosive, leaving behind a dead zone. The detonation front farther out from the corner slowly turns and eventually reaches the air well edge 180{sup o} from its original direction. The dead zone is stable and persists 7.7 {micro}s after the corner-turn, although it has drifted into the original air well area. Our regular reactive flow computer models sometimes show temporary failure but they recover quickly and are unable to model the dead zones. We present a failure model that cuts off the reaction rate below certain detonation velocities and reproduces the qualitative features of the corner-turning failure.

  6. Wave Propagation in Multiferroic Materials

    E-Print Network [OSTI]

    Keller, Scott Macklin

    2013-01-01

    Waves in Magnetoelectric Materials . . . Need forApplication of Multiferroic Materials to Receive AntennaMaterials . . . . . . . . . . . . . . . . . . . . . . . . .

  7. 01-12-2000 - Mechanical Failure of Supplied Air Fitting | The...

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

    2000 - Mechanical Failure of Supplied Air Fitting Document Number: NA Effective Date: 012000 File (public): 01-12-2000...

  8. Patient-specific modeling of cardiac electromechanics in dyssynchronous heart failure

    E-Print Network [OSTI]

    Shin, Jun Seob

    2009-01-01

    1.3 Congestive Heart1.1: Longitudinal cross-section of the heart . . . . . . .Classification of heart failure . . . . . . . . . . . .

  9. Testing branching process estimators of cascading failure with data from a

    E-Print Network [OSTI]

    Dobson, Ian

    the propagation of cascading transmission line failures in large blackouts of electric power systems. We use failures that successively weaken a system. In electric power transmission systems, cascading failure]. Electric power transmission systems are meshed networks at high voltages that form the backbone

  10. FUNCTIONAL COMPLEXITY FAILURES AND AUTOMATION SURPRISES: THE MYSTERIOUS CASE OF CONTROLLED FLIGHT INTO STALL (CFIS)

    E-Print Network [OSTI]

    1 FUNCTIONAL COMPLEXITY FAILURES AND AUTOMATION SURPRISES: THE MYSTERIOUS CASE OF CONTROLLED FLIGHT of behaviors of the automation functions. There were no consistent: failures that triggered the events (e.g. sensor failures), effects of triggering events on the automation (e.g. mode change), or commands issued

  11. Wind Turbine Bearing Failure Detection Using Generator Stator Current Homopolar Component

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Wind Turbine Bearing Failure Detection Using Generator Stator Current Homopolar Component Ensemble Empirical Mode Decomposition (EEMD) as a tool for failure detection in wind turbine generators for stationary and non stationary cases. Index Terms-Wind turbine, induction generator, bearing failure, ensemble

  12. Controller Failure Time Analysis for Symmetric H Control Systems Guisheng ZHAI

    E-Print Network [OSTI]

    Antsaklis, Panos

    Controller Failure Time Analysis for Symmetric H Control Systems Guisheng ZHAI Department of Opto a controller failure time analysis problem for a class of symmetric linear time-invariant (LTI) systems properties for the entire system. Our objective is to find conditions concerning controller failure time

  13. Edinburgh Research Explorer Global association of air pollution and heart failure

    E-Print Network [OSTI]

    Edinburgh, University of

    Edinburgh Research Explorer Global association of air pollution and heart failure Citation & Mills, NL 2013, 'Global association of air pollution and heart failure: a systematic review and meta-6736(13)60898-3 1 Global association of air pollution and heart failure: a systematic review and meta-analysis Anoop

  14. Zheng, Wang, Nihan, and Hallenbeck 1 Detecting Cycle Failures at Signalized Intersections Using Video Image Processing

    E-Print Network [OSTI]

    Washington at Seattle, University of

    captured all the cycle failures and generated only three false alarms, which is approximately 0Zheng, Wang, Nihan, and Hallenbeck 1 Detecting Cycle Failures at Signalized Intersections Using-5965 tracmark@u.washington.edu #12;Zheng, Wang, Nihan, and Hallenbeck 2 ABSTRACT: Signal cycle failure (or

  15. To appear in The Electricity Journal, Dec. 2003 Cascading Failures: Survival vs. Prevention

    E-Print Network [OSTI]

    be taken to reduce the number of large-scale power losses due to failures of the generation and high1 To appear in The Electricity Journal, Dec. 2003 Cascading Failures: Survival vs. Prevention voltage transmission grid such as the August 14, 2003 blackout. However, such failures cannot

  16. Tsunami Generation by Submarine Mass Failure. II: Predictive Equations and Case Studies

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Tsunami Generation by Submarine Mass Failure. II: Predictive Equations and Case Studies Philip generation by submarine mass failure SMF that are only valid in the vicinity of the tsunami sources. We give generated by submarine mass failures SMFs have received increased scrutiny in the research commu- nity

  17. Using Groupings of Static Analysis Alerts to Identify Files Likely to Contain Field Failures

    E-Print Network [OSTI]

    Sherriff, Mark S.

    of a field failure. Our technique uses singular value decomposition to generate groupings of static analysisUsing Groupings of Static Analysis Alerts to Identify Files Likely to Contain Field Failures Mark S@csc.ncsu.edu ABSTRACT In this paper, we propose a technique for leveraging historical field failure records

  18. CONTROL OF SPACECRAFT SUBJECT TO ACTUATOR FAILURES: STATE-OF-THE-ART

    E-Print Network [OSTI]

    Tsiotras, Panagiotis

    trajectory generation problem for a spacecraft with one actuator failure. We present several numerical examCONTROL OF SPACECRAFT SUBJECT TO ACTUATOR FAILURES: STATE-OF-THE-ART AND OPEN PROBLEMS Panagiotis In this paper we review the main results in the area of active control of spacecraft with one actuator failure

  19. Recovery from Shared Risk Link Group Failures using IP Fast Reroute

    E-Print Network [OSTI]

    Chao, Jonathan

    and randomly generated topologies. Index Terms--routing, failure recovery, shared risk link group (SRLG), fastRecovery from Shared Risk Link Group Failures using IP Fast Reroute Kang Xi, H. Jonathan Chao}@poly.edu, cguo01@students.poly.edu Abstract--Failure recovery in IP networks is critical to high- quality service

  20. A Probabilistic Model for the Dynamics of Cascading Failures and Blackouts in Power Grids

    E-Print Network [OSTI]

    Hayat, Majeed M.

    cause failures of power system components such as transmission lines and generators, which, in turn, may1 A Probabilistic Model for the Dynamics of Cascading Failures and Blackouts in Power Grids Mahshid Abstract--Current power grids suffer periodic disturbances that may trigger cascades of component failures

  1. Protector: A Probabilistic Failure Detector for Cost-Effective Peer-to-Peer Storage

    E-Print Network [OSTI]

    Zhao, Ben Y.

    replicas as needed to compensate for others lost to peer failures. Since replica generation consumesProtector: A Probabilistic Failure Detector for Cost-Effective Peer-to-Peer Storage Zhi Yang, Jing availability, additional replicas must be created when peers fail. Since the majority of failures in P2P

  2. Patterns of Failure After Concurrent Bevacizumab and Hypofractionated Stereotactic Radiation Therapy for Recurrent High-Grade Glioma

    SciTech Connect (OSTI)

    Shapiro, Lauren Q.; Beal, Kathryn; Goenka, Anuj; Karimi, Sasan; Iwamoto, Fabio M.; Yamada, Yoshiya; Zhang, Zhigang; Lassman, Andrew B.; Abrey, Lauren E.; Gutin, Philip H.

    2013-03-01

    Purpose: Concurrent bevacizumab with hypofractionated stereotactic radiation therapy (HSRT) is safe and effective for the treatment of recurrent high-grade gliomas (HGG). The objective of this study was to characterize the patterns of failure after this treatment regimen. Methods and Materials: Twenty-four patients with recurrent enhancing HGG were previously treated on an institutional review board-approved protocol of concurrent bevacizumab and reirradiation. Patients received 30 Gy in 5 fractions to the recurrent tumor with HSRT. Brain magnetic resonance imaging (MRI) was performed every 2 cycles, and bevacizumab was continued until clinical or radiographic tumor progression according to the criteria of Macdonald et al. MRI at the time of progression was fused to the HSRT treatment plan, and the location of recurrence was classified on the basis of volume within the 95% isodose line. Outcomes based on patient characteristics, tumor grade, recurrence pattern, and best response to treatment were analyzed by the Kaplan-Meier method. Results: Twenty-two patients experienced either clinical or radiographic progression. Recurrent tumor was enhancing in 15 (71.4%) and nonenhancing in 6 (28.6%) patients. Eleven patients (52.4%) had recurrence within the radiation field, 5 patients (23.8%) had marginal recurrence, and 5 patients had recurrence outside the radiation field. Pattern of enhancement and location of failure did not correlate with overall survival or progression-free survival. Radiographic response was the only variable to significantly correlate with progression-free survival. Conclusions: Despite the promising initial response seen with the addition of HSRT to bevacizumab as salvage treatment for recurrent HGG, approximately half of patients ultimately still experience failure within the radiation field. The rate of local failure with the addition of HSRT seems to be lower than that seen with bevacizumab alone in the salvage setting. Our data underscore the radioresistance of HGG and the need for better salvage treatments.

  3. Transporting particulate material

    DOE Patents [OSTI]

    Aldred, Derek Leslie (North Hollywood, CA); Rader, Jeffrey A. (North Hollywood, CA); Saunders, Timothy W. (North Hollywood, CA)

    2011-08-30

    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  4. Nanocrystalline ceramic materials

    DOE Patents [OSTI]

    Siegel, Richard W. (Hinsdale, IL); Nieman, G. William (Evanston, IL); Weertman, Julia R. (Evanston, IL)

    1994-01-01

    A method for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material.

  5. Experiments on Corium Dispersion after Lower Head Failure at Moderate Pressure

    SciTech Connect (OSTI)

    BLANCHAT,THOMAS K.; GARGALLO,M.; JACOBS,G.; MEYER,L.; WILHELM,D.

    1999-09-21

    Concerning the mitigation of high pressure core melt scenarios, the design objective for future PWRS is to transfer high pressure core melt to low pressure core melt sequences, by means of pressure relief valves at the primary circuit, with such a discharge capacity to limit the pressure in the reactor coolant system to less than 20 bar. Studies have shown that in late in-vessel reflooding scenarios there may be a time window where the pressure is indeed in this range, at the moment of the reactor vessel rupture. It has to be verified that large quantities of corium released from the vessel after failure at pressures <20 bar cannot be carried out of the reactor pit, because the melt collecting and cooling concept of future PWRs would be rendered useless. Existing experiments investigated the melt dispersal phenomena in the context of the DCH resolution for existing power plants in the USA, most of them having cavities with large instrument tunnels leading into subcompartments. For such designs, breaches with small cross sections at high vessel failure pressures had been studied. However, some present and future European PWRs have an annular cavity design without a large pathway out of the cavity other than through the narrow annular gap between the RPV and the cavity wall. Therefore, an experimental program was launched, focusing on the annular cavity design and low pressure vessel failure. The first part of the program comprises two experiments which were performed with thermite melt steam and a prototypic atmosphere in the containment in a scale 1:10. The initial pressure in the RPV-model was 11 and 15 bars, and the breach was a hole at the center of the lower head with a scaled diameter of 100 cm and 40 cm, respectively. The main results were: 78% of melt mass were ejected out of the cavity with the large hole and 21% with the small hole; the maximum pressures in the model containment were 6 bar and 4 bar, respectively. In the second part of the experimental program a detailed investigation of geometry effects is being carried out. The test facility DISCO-C has been built for performing dispersion experiments with cold simulant materials in a 1/18 scale. The fluids are water or bismuth alloy instead of melt, and nitrogen or helium instead of steam.

  6. Effect of Component Failures on Economics of Distributed Photovoltaic Systems

    SciTech Connect (OSTI)

    Lubin, Barry T.

    2012-02-02

    This report describes an applied research program to assess the realistic costs of grid connected photovoltaic (PV) installations. A Board of Advisors was assembled that included management from the regional electric power utilities, as well as other participants from companies that work in the electric power industry. Although the program started with the intention of addressing effective load carrying capacity (ELCC) for utility-owned photovoltaic installations, results from the literature study and recommendations from the Board of Advisors led investigators to the conclusion that obtaining effective data for this analysis would be difficult, if not impossible. The effort was then re-focused on assessing the realistic costs and economic valuations of grid-connected PV installations. The 17 kW PV installation on the University of Hartford's Lincoln Theater was used as one source of actual data. The change in objective required a more technically oriented group. The re-organized working group (changes made due to the need for more technically oriented participants) made site visits to medium-sized PV installations in Connecticut with the objective of developing sources of operating histories. An extensive literature review helped to focus efforts in several technical and economic subjects. The objective of determining the consequences of component failures on both generation and economic returns required three analyses. The first was a Monte-Carlo-based simulation model for failure occurrences and the resulting downtime. Published failure data, though limited, was used to verify the results. A second model was developed to predict the reduction in or loss of electrical generation related to the downtime due to these failures. Finally, a comprehensive economic analysis, including these failures, was developed to determine realistic net present values of installed PV arrays. Two types of societal benefits were explored, with quantitative valuations developed for both. Some societal benefits associated with financial benefits to the utility of having a distributed generation capacity that is not fossil-fuel based have been included into the economic models. Also included and quantified in the models are several benefits to society more generally: job creation and some estimates of benefits from avoiding greenhouse emissions. PV system failures result in a lowering of the economic values of a grid-connected system, but this turned out to be a surprisingly small effect on the overall economics. The most significant benefit noted resulted from including the societal benefits accrued to the utility. This provided a marked increase in the valuations of the array and made the overall value proposition a financially attractive one, in that net present values exceeded installation costs. These results indicate that the Department of Energy and state regulatory bodies should consider focusing on societal benefits that create economic value for the utility, confirm these quantitative values, and work to have them accepted by the utilities and reflected in the rate structures for power obtained from grid-connected arrays. Understanding and applying the economic benefits evident in this work can significantly improve the business case for grid-connected PV installations. This work also indicates that the societal benefits to the population are real and defensible, but not nearly as easy to justify in a business case as are the benefits that accrue directly to the utility.

  7. Nanostructured magnetic materials

    E-Print Network [OSTI]

    Chan, Keith T.

    2011-01-01

    Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

  8. Department of Materials Science &

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    Developing Leaders of Innovation Department of Materials Science & Engineering #12;At the University of Virginia, students in materials science, engineering physics and engineering science choose to tackle compelling issues in materials science and engineering or engineering science

  9. Sandia Energy - Materials Chemistry

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

    Materials Chemistry Home Transportation Energy Predictive Simulation of Engines Clean FuelsPower Materials Chemistry Materials ChemistryAshley Otero2015-10-28T02:42:21+00:00...

  10. Polymer Filler Aging and Failure Studied by Lateral Force Microscopy

    SciTech Connect (OSTI)

    Ratto, T; Saab, A P

    2009-05-27

    In the present work, we study, via force microscopy, the basic physical interactions of a single bead of silica filler with a PDMS matrix both before and after exposure to gamma radiation. Our goal was to confirm our results from last year, and to explore force microscopy as a means of obtaining particle-scale polymer/filler interactions suitable for use as empirical inputs to a computational model consisting of an ensemble of silica beads embedded in a PDMS matrix. Through careful calibration of a conventional atomic force microscope, we obtained both normal and lateral force data that was fitted to yield adhesion, surface shear modulus, and friction of a 1 {micro}m silica bead in contact with PDMS layers of various thickness. Comparison of these terms before and after gamma exposure indicated that initially, radiation exposure lead to softening of the PDMS, but eventually resulted in stiffening. Simultaneously, adhesion between the polymer and silica decreased. This could indicate a serious failure path for filled PDMS exposed to radiation, whereby stiffening of the bulk polymer leads to loss of compressive elastic behavior, while a decrease in polymer filler adhesion results in an increased likelihood of stress failure under load. In addition to further testing of radiation damaged polymers, we also performed FEA modeling of silica beads in a silicone matrix using the shear modulus and adhesion values isolated from the force microscopy experiments as model inputs. The resulting simulation indicated that as a polymer stiffens due to impinging radiation, it also undergoes weakening of adhesion to the filler. The implication is that radiation induces a compound failure mode in filled polymer systems.

  11. Failure and Reliability Analysis for the Master Pump Shutdown System

    SciTech Connect (OSTI)

    BEVINS, R.R.

    2000-09-05

    The Master Pump Shutdown System (MPSS) will be installed in the 200 Areas of the Hanford Site to monitor and control the transfer of liquid waste between tank farms and between the 200 West and 200 East areas through the Cross-Site Transfer Line. The Safety Function provided by the MPSS is to shutdown any waste transfer process within or between tank farms if a waste leak should occur along the selected transfer route. The MPSS, which provides this Safety Class Function, is composed of Programmable Logic Controllers (PLCs), interconnecting wires, relays, Human to Machine Interfaces (HMI), and software. These components are defined as providing a Safety Class Function and will be designated in this report as MPSS/PLC. Input signals to the MPSS/PLC are provided by leak detection systems from each of the tank farm leak detector locations along the waste transfer route. The combination of the MPSS/PLC, leak detection system, and transfer pump controller system will be referred to as MPSS/SYS. The components addressed in this analysis are associated with the MPSS/SYS. The purpose of this failure and reliability analysis is to address the following design issues of the Project Development Specification (PDS) for the MPSS/SYS (HNF 2000a): (1) Single Component Failure Criterion, (2) System Status Upon Loss of Electrical Power, (3) Physical Separation of Safety Class cables, (4) Physical Isolation of Safety Class Wiring from General Service Wiring, and (5) Meeting the MPSS/PLC Option 1b (RPP 1999) Reliability estimate. The failure and reliability analysis examined the system on a component level basis and identified any hardware or software elements that could fail and/or prevent the system from performing its intended safety function.

  12. Weld monitor and failure detector for nuclear reactor system

    DOE Patents [OSTI]

    Sutton, Jr., Harry G. (Mt. Lebanon, PA)

    1987-01-01

    Critical but inaccessible welds in a nuclear reactor system are monitored throughout the life of the reactor by providing small aperture means projecting completely through the reactor vessel wall and also through the weld or welds to be monitored. The aperture means is normally sealed from the atmosphere within the reactor. Any incipient failure or cracking of the weld will cause the environment contained within the reactor to pass into the aperture means and thence to the outer surface of the reactor vessel where its presence is readily detected.

  13. Analysis of damage and failure in metal matrix composites

    SciTech Connect (OSTI)

    Brust, F.W.; Majumdar, B.S.; Newaz, G.M.

    1995-12-31

    This paper presents the results of the analysis of the constitutive response of a model Metal Matrix Composite (MMC) system. The model is described first, followed by some direct comparison of predicted response to corresponding experimental data. An important result discussed here is that when model verification is made, it is important to compare load direction response to the experimental data, but also, comparisons to the out of load direction response must be made, or the model may not be performing as desired. Some discussion of failure predictions using simple models is also made here.

  14. Acute Liver Failure After a Late TIPSS Revision

    SciTech Connect (OSTI)

    Radeleff, Boris, E-mail: Boris_radeleff@med.uni-heidelberg.de; Sommer, Christof-Matthias; Schawo, Simone; Lopez-Benitez, Ruben [University of Heidelberg, Department of Diagnostic Radiology (Germany); Sauer, Peter [University of Heidelberg, Departments of Internal Medicine IV, Gastroenterology, Hepatology, Infectious Diseases, Intoxications (Germany); Schemmer, Peter [University of Heidelberg, Department of Surgery (Germany); Kauffmann, Guenter W.; Richter, Goetz M. [University of Heidelberg, Department of Diagnostic Radiology (Germany)

    2008-01-15

    We report a rare case of late transjugular intrahepatic portosystemic stent shunt (TIPSS) occlusion due to progressive stent protrusion into the periportal liver parenchyma, which was a result of delayed liver shrinkage 2 years after TIPSS. The initial TIPSS procedure had been carried out in a 52-year-old man as a bridge for liver transplantation because of post-alcoholic liver cirrhosis. We describe the applied TIPSS recanalization and revision technique. Immediately after TIPSS revision acute liver failure developed, which required emergency liver transplantation.

  15. Component failures at pressurized water reactors. Final report

    SciTech Connect (OSTI)

    Reisinger, M.F.

    1980-10-01

    Objectives of this study were to identify those systems having major impact on safety and availability (i.e. to identify those systems and components whose failures have historically caused the greatest number of challenges to the reactor protective systems and which have resulted in greatest loss of electric generation time). These problems were identified for engineering solutions and recommendations made for areas and programs where research and development should be concentrated. The program was conducted in three major phases: Data Analysis, Engineering Evaluation, Cost Benefit Analysis.

  16. Nuclear Materials: Reconsidering Wastes and Assets - 13193

    SciTech Connect (OSTI)

    Michalske, T.A. [Savannah River National Laboratory (United States)] [Savannah River National Laboratory (United States)

    2013-07-01

    The nuclear industry, both in the commercial and the government sectors, has generated large quantities of material that span the spectrum of usefulness, from highly valuable ('assets') to worthless ('wastes'). In many cases, the decision parameters are clear. Transuranic waste and high level waste, for example, have no value, and is either in a final disposition path today, or - in the case of high level waste - awaiting a policy decision about final disposition. Other materials, though discardable, have intrinsic scientific or market value that may be hidden by the complexity, hazard, or cost of recovery. An informed decision process should acknowledge the asset value, or lack of value, of the complete inventory of materials, and the structure necessary to implement the range of possible options. It is important that informed decisions are made about the asset value for the variety of nuclear materials available. For example, there is a significant quantity of spent fuel available for recycle (an estimated $4 billion value in the Savannah River Site's (SRS) L area alone); in fact, SRS has already blended down more than 300 metric tons of uranium for commercial reactor use. Over 34 metric tons of surplus plutonium is also on a path to be used as commercial fuel. There are other radiological materials that are routinely handled at the site in large quantities that should be viewed as strategically important and / or commercially viable. In some cases, these materials are irreplaceable domestically, and failure to consider their recovery could jeopardize our technological leadership or national defense. The inventories of nuclear materials at SRS that have been characterized as 'waste' include isotopes of plutonium, uranium, americium, and helium. Although planning has been performed to establish the technical and regulatory bases for their discard and disposal, recovery of these materials is both economically attractive and in the national interest. (authors)

  17. Transporting Hazardous Materials

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

    Transporting Hazardous Materials The procedures given below apply to all materials that are considered to be hazardous by the U.S. Department of Transportation (DOT). Consult your...

  18. Institute for Materials Science

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

    Security Education Center About Us Conferences and Workshops Advanced Qualification of Additive Manufacturing Materials Workshop Quantum and Dirac Materials for Energy...

  19. Materials Physics and Applications

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

    MPA Materials Physics and Applications We develop new technologies that solve pressing national energy and security challenges by exploring and exploiting materials and their...

  20. Test-to-Failure of Crystalline Silicon Modules: Preprint

    SciTech Connect (OSTI)

    Hacke, P.; Terwilliger, K.; Glick, S.; Trudell, D.; Bosco, N.; Johnston, S.; Kurtz, S. R.

    2010-10-01

    Accelerated lifetime testing of five crystalline silicon module designs was carried out according to the Terrestrial Photovoltaic Module Accelerated Test-to-Failure Protocol. This protocol compares the reliability of various module constructions on a quantitative basis. The modules under test are subdivided into three accelerated lifetime testing paths: 85..deg..C/85% relative humidity with system bias, thermal cycling between ?40..deg..C and 85..deg..C, and a path that alternates between damp heat and thermal cycling. The most severe stressor is damp heat with system bias applied to simulate the voltages that modules experience when connected in an array. Positive 600 V applied to the active layer with respect to the grounded module frame accelerates corrosion of the silver grid fingers and degrades the silicon nitride antireflective coating on the cells. Dark I-V curve fitting indicates increased series resistance and saturation current around the maximum power point; however, an improvement in junction recombination characteristics is obtained. Shunt paths and cell-metallization interface failures are seen developing in the silicon cells as determined by electroluminescence, thermal imaging, and I-V curves in the case of negative 600 V bias applied to the active layer. Ability to withstand electrolytic corrosion, moisture ingress, and ion drift under system voltage bias are differentiated.

  1. Photomultiplier tube failure under hydrostatic pressure in future neutrino detectors

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

    Chambliss, K. [Alfred Univ., Alfred, NY (United States). Multifunctional Materials Lab, Kazuo Inamori School of Engineering; Diwan, M. [Alfred Univ., Alfred, NY (United States). Multifunctional Materials Lab, Kazuo Inamori School of Engineering; Simos, N. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Sundaram, S. K. [Alfred Univ., Alfred, NY (United States). Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2014-10-01

    Failure of photomultiplier tubes (PMTs) under hydrostatic pressure is a concern in neutrino detection, specifically, in the proposed Long-Baseline Neutrino Experiment project. Controlled hydrostatic implosion tests were performed on prototypic PMT bulbs of 10-inch diameter and recorded using high speed filming techniques to capture failures in detail. These high-speed videos were analyzed frame-by-frame in order to identify the origin of a crack, measure the progression of individual crack along the surface of the bulb as it propagates through the glass, and estimate crack velocity. Crack velocity was calculated for each individual crack, and an average velocity was determined for all measurable cracks on each bulb. Overall, 32 cracks were measured in 9 different bulbs tested. Finite element modeling (FEM) of crack formation and growth in prototypic PMT shows stress concentration near the middle section of the PMT bulbs that correlates well with our crack velocity measurements in that section. The FEM model predicts a crack velocity value that is close to the terminal crack velocity reported. Our measurements also reveal significantly reduced crack velocities compared to terminal crack velocities measured in glasses using fracture mechanics testing and reported in literature.

  2. Photomultiplier tube failure under hydrostatic pressure in future neutrino detectors

    SciTech Connect (OSTI)

    Chambliss, K.; Diwan, M.; Simos, N.; Sundaram, S. K.

    2014-10-09

    Failure of photomultiplier tubes (PMTs) under hydrostatic pressure is a concern in neutrino detection, specifically, in the proposed Long-Baseline Neutrino Experiment project. Controlled hydrostatic implosion tests were performed on prototypic PMT bulbs of 10-inch diameter and recorded using high speed filming techniques to capture failures in detail. These high-speed videos were analyzed frame-by-frame in order to identify the origin of a crack, measure the progression of individual crack along the surface of the bulb as it propagates through the glass, and estimate crack velocity. Crack velocity was calculated for each individual crack, and an average velocity was determined for all measurable cracks on each bulb. Overall, 32 cracks were measured in 9 different bulbs tested. Finite element modeling (FEM) of crack formation and growth in prototypic PMT shows stress concentration near the middle section of the PMT bulbs that correlates well with our crack velocity measurements in that section. The FEM model predicts a crack velocity value that is close to the terminal crack velocity reported. Our measurements also reveal significantly reduced crack velocities compared to terminal crack velocities measured in glasses using fracture mechanics testing and reported in literature.

  3. RECONFIGURING POWER SYSTEMS TO MINIMIZE CASCADING FAILURES: MODELS AND ALGORITHMS

    SciTech Connect (OSTI)

    Bienstock, Daniel

    2014-04-11

    the main goal of this project was to develop new scientific tools, based on optimization techniques, with the purpose of controlling and modeling cascading failures of electrical power transmission systems. We have developed a high-quality tool for simulating cascading failures. The problem of how to control a cascade was addressed, with the aim of stopping the cascade with a minimum of load lost. Yet another aspect of cascade is the investigation of which events would trigger a cascade, or more appropriately the computation of the most harmful initiating event given some constraint on the severity of the event. One common feature of the cascade models described (indeed, of several of the cascade models found in the literature) is that we study thermally-induced line tripping. We have produced a study that accounts for exogenous randomness (e.g. wind and ambient temperature) that could affect the thermal behavior of a line, with a focus on controlling the power flow of the line while maintaining safe probability of line overload. This was done by means of a rigorous analysis of a stochastic version of the heat equation. we incorporated a model of randomness in the behavior of wind power output; again modeling an OPF-like problem that uses chance-constraints to maintain low probability of line overloads; this work has been continued so as to account for generator dynamics as well.

  4. Photomultiplier tube failure under hydrostatic pressure in future neutrino detectors

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

    Chambliss, K.; Diwan, M.; Simos, N.; Sundaram, S. K.

    2014-10-09

    Failure of photomultiplier tubes (PMTs) under hydrostatic pressure is a concern in neutrino detection, specifically, in the proposed Long-Baseline Neutrino Experiment project. Controlled hydrostatic implosion tests were performed on prototypic PMT bulbs of 10-inch diameter and recorded using high speed filming techniques to capture failures in detail. These high-speed videos were analyzed frame-by-frame in order to identify the origin of a crack, measure the progression of individual crack along the surface of the bulb as it propagates through the glass, and estimate crack velocity. Crack velocity was calculated for each individual crack, and an average velocity was determined for allmore »measurable cracks on each bulb. Overall, 32 cracks were measured in 9 different bulbs tested. Finite element modeling (FEM) of crack formation and growth in prototypic PMT shows stress concentration near the middle section of the PMT bulbs that correlates well with our crack velocity measurements in that section. The FEM model predicts a crack velocity value that is close to the terminal crack velocity reported. Our measurements also reveal significantly reduced crack velocities compared to terminal crack velocities measured in glasses using fracture mechanics testing and reported in literature.« less

  5. ISSUES ASSOCIATED WITH PROBABILISTIC FAILURE MODELING OF DIGITAL SYSTEMS

    SciTech Connect (OSTI)

    CHU,T.L.; MARTINEZ-GURIDI,G.; LEHNER,J.; OVERLAND,D.

    2004-09-19

    The current U.S. Nuclear Regulatory Commission (NRC) licensing process of instrumentation and control (I&C) systems is based on deterministic requirements, e.g., single failure criteria, and defense in depth and diversity. Probabilistic considerations can be used as supplements to the deterministic process. The National Research Council has recommended development of methods for estimating failure probabilities of digital systems, including commercial off-the-shelf (COTS) equipment, for use in probabilistic risk assessment (PRA). NRC staff has developed informal qualitative and quantitative requirements for PRA modeling of digital systems. Brookhaven National Laboratory (BNL) has performed a review of the-state-of-the-art of the methods and tools that can potentially be used to model digital systems. The objectives of this paper are to summarize the review, discuss the issues associated with probabilistic modeling of digital systems, and identify potential areas of research that would enhance the state of the art toward a satisfactory modeling method that could be integrated with a typical probabilistic risk assessment.

  6. The Impact of Preradiation Residual Disease Volume on Time to Locoregional Failure in Cutaneous Merkel Cell Carcinoma—A TROG Substudy

    SciTech Connect (OSTI)

    Finnigan, Renee; Hruby, George; Wratten, Chris; Keller, Jacqui; Tripcony, Lee; Dickie, Graeme; Rischin, Danny; Poulsen, Michael

    2013-05-01

    Purpose: This study evaluated the impact of margin status and gross residual disease in patients treated with chemoradiation therapy for high-risk stage I and II Merkel cell cancer (MCC). Methods and Materials: Data were pooled from 3 prospective trials in which patients were treated with 50 Gy in 25 fractions to the primary lesion and draining lymph nodes and 2 schedules of carboplatin based chemotherapy. Time to locoregional failure was analyzed according to the burden of disease at the time of radiation therapy, comparing patients with negative margins, involved margins, or macroscopic disease. Results: Analysis was performed on 88 patients, of whom 9 had microscopically positive resection margins and 26 had macroscopic residual disease. The majority of gross disease was confined to nodal regions. The 5-year time to locoregional failure, time to distant failure, time to progression, and disease-specific survival rates for the whole group were 73%, 69%, 62%, and 66% respectively. The hazard ratio for macroscopic disease at the primary site or the nodes was 1.25 (95% confidence interval 0.57-2.77), P=.58. Conclusions: No statistically significant differences in time to locoregional failure were identified between patients with negative margins and those with microscopic or gross residual disease. These results must, however, be interpreted with caution because of the limited sample size.

  7. Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Poster)

    SciTech Connect (OSTI)

    Miller, D. C.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

    2011-02-01

    Polymeric encapsulation materials are typically used in concentrating photovoltaic (CPV) modules to protect the cell from the field environment. Because it is physically located adjacent to the cell, the encapsulation is exposed to a high optical flux, often including light in the ultraviolet (UV) and infrared (IR) wavelengths. The durability of encapsulants used in CPV modules is critical to the technology, but is presently not well understood. This work seeks to identify the appropriate material types, field-induced failure mechanisms, and factors of influence (if possible) of polymeric encapsulation. These results will ultimately be weighed against those of future qualification and accelerated life test procedures.

  8. HAZARDOUS MATERIALS EMERGENCY RESPONSE

    E-Print Network [OSTI]

    ANNEX Q HAZARDOUS MATERIALS EMERGENCY RESPONSE #12;ANNEX Q - HAZARDOUS MATERIALS EMERGENCY RESPONSE 03/10/2014 v.2.0 Page Q-1 PROMULGATION STATEMENT Annex Q: Hazardous Materials Emergency Response, and contents within, is a guide to how the University conducts a response specific to a hazardous materials

  9. Materials Science & Engineering

    E-Print Network [OSTI]

    Materials Science & Engineering In this presentation the role of materials in power generation sector is about 20%, opportunities for materials-based technologies to improve energy efficiency (e Ridge National Laboratory (ORNL). He is also the Director of the High Temperature Materials Laboratory

  10. Tritium breeding materials

    SciTech Connect (OSTI)

    Hollenberg, G.W.; Johnson, C.E.; Abdou, M.

    1984-03-01

    Tritium breeding materials are essential to the operation of D-T fusion facilities. Both of the present options - solid ceramic breeding materials and liquid metal materials are reviewed with emphasis not only on their attractive features but also on critical materials issues which must be resolved.

  11. CRAD, Packaging and Transfer of Hazardous Materials and Materials...

    Office of Environmental Management (EM)

    Packaging and Transfer of Hazardous Materials and Materials of National Security Interest Assessment Plan CRAD, Packaging and Transfer of Hazardous Materials and Materials of...

  12. IEEE/ACM TRANSACTIONS ON NETWORKING, VOL. 16, NO. 4, AUGUST 2008 749 Characterization of Failures in an Operational

    E-Print Network [OSTI]

    Chuah, Chen-Nee

    of the different classes provides a probabilistic failure model, which can be used to generate realistic failureIEEE/ACM TRANSACTIONS ON NETWORKING, VOL. 16, NO. 4, AUGUST 2008 749 Characterization of Failures services, its dependability in the presence of various failures becomes crit- ical. In this paper, we

  13. Puncture detecting barrier materials

    DOE Patents [OSTI]

    Hermes, R.E.; Ramsey, D.R.; Stampfer, J.F.; Macdonald, J.M.

    1998-03-31

    A method and apparatus for continuous real-time monitoring of the integrity of protective barrier materials, particularly protective barriers against toxic, radioactive and biologically hazardous materials has been developed. Conductivity, resistivity or capacitance between conductive layers in the multilayer protective materials is measured by using leads connected to electrically conductive layers in the protective barrier material. The measured conductivity, resistivity or capacitance significantly changes upon a physical breach of the protective barrier material. 4 figs.

  14. Puncture detecting barrier materials

    DOE Patents [OSTI]

    Hermes, Robert E. (Los Alamos, NM); Ramsey, David R. (Bothel, WA); Stampfer, Joseph F. (Santa Fe, NM); Macdonald, John M. (Santa Fe, NM)

    1998-01-01

    A method and apparatus for continuous real-time monitoring of the integrity of protective barrier materials, particularly protective barriers against toxic, radioactive and biologically hazardous materials has been developed. Conductivity, resistivity or capacitance between conductive layers in the multilayer protective materials is measured by using leads connected to electrically conductive layers in the protective barrier material. The measured conductivity, resistivity or capacitance significantly changes upon a physical breach of the protective barrier material.

  15. Nanocrystalline ceramic materials

    DOE Patents [OSTI]

    Siegel, R.W.; Nieman, G.W.; Weertman, J.R.

    1994-06-14

    A method is disclosed for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material. 19 figs.

  16. Preliminary Failure Modes and Effects Analysis of the US Massive Gas Injection Disruption Mitigation System Design

    SciTech Connect (OSTI)

    Lee C. Cadwallader

    2013-10-01

    This report presents the results of a preliminary failure modes and effects analysis (FMEA) of a candidate design for the ITER Disruption Mitigation System. This candidate is the Massive Gas Injection System that provides machine protection in a plasma disruption event. The FMEA was quantified with “generic” component failure rate data as well as some data calculated from operating facilities, and the failure events were ranked for their criticality to system operation.

  17. Preliminary Failure Modes and Effects Analysis of the US DCLL Test Blanket Module

    SciTech Connect (OSTI)

    Lee C. Cadwallader

    2010-06-01

    This report presents the results of a preliminary failure modes and effects analysis (FMEA) of a small tritium-breeding test blanket module design for the International Thermonuclear Experimental Reactor. The FMEA was quantified with “generic” component failure rate data, and the failure events are binned into postulated initiating event families and frequency categories for safety assessment. An appendix to this report contains repair time data to support an occupational radiation exposure assessment for test blanket module maintenance.

  18. Failure prediction of cross-rolled beryllium sheets subjected to transverse point loads 

    E-Print Network [OSTI]

    Mascorro, Edward

    1991-01-01

    advantage of this formulation is its ability to take into account interdependence of the failure stress components. Previous theories assume that biaxially loaded specimens have failure surfaces that are only functions of the uniaxial failure stresses.... It is shown in section 2 that cross-rolled beryllium is stronger when it is loaded biaxially than when loaded uniaxially. Although previous theories can not describe this phenomenon, the Tsai-Wu formulation is simple yet flexible enough to model...

  19. Component Failure Rate Data Sources for Probabilistic Safety and Reliability

    SciTech Connect (OSTI)

    L. C. Cadwallader; S. A. Eide

    2010-09-01

    Probabilistic safety methods are being used in several industries, including chemical, manufacturing, and energy. When performing reliability studies or using probabilistic safety approaches, a basic need arises for input data on failure rates of the mechanical, electrical, instrumentation and control, and other components that comprise the engineering systems in the facility. Some companies have many types of data stored and can retrieve these in-house data for such uses. Other companies hire consultants to perform safety assessments; the consulting firms often use their own data bases. For those analysts who do not have either of those options available, this paper presents some data sources that are retrievable from the literature. These data sources have been evaluated with a basic rating of usefulness for analysis work, and each has a description of what data can be found in the citation that can be used to support assessments in industry. The accessibility of data documents via the internet is also described.

  20. Cascade Failures from Distributed Generation in Power Grids

    E-Print Network [OSTI]

    Scala, Antonio; Scoglio, Caterina

    2012-01-01

    Power grids are nowadays experiencing a transformation due to the introduction of Distributed Generation based on Renewable Sources. At difference with classical Distributed Generation, where local power sources mitigate anomalous user consumption peaks, Renewable Sources introduce in the grid intrinsically erratic power inputs. By introducing a simple schematic (but realistic) model for power grids with stochastic distributed generation, we study the effects of erratic sources on the robustness of several IEEE power grid test networks with up to 2000 buses. We find that increasing the penetration of erratic sources causes the grid to fail with a sharp transition. We compare such results with the case of failures caused by the natural increasing power demand.

  1. Joining of dissimilar materials

    DOE Patents [OSTI]

    Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

    2012-10-16

    A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

  2. APC mutations lead to cytokinetic failures in vitro and tetraploid genotypes in Min mice

    E-Print Network [OSTI]

    Caldwell, Christine M; Green, Rebecca A; Kaplan, Kenneth B

    2007-01-01

    JCB: ARTICLE APC mutations lead to cytokinetic failures inpre- cise mechanisms that lead to the chromosomal defects inanaphase begins. APC MUTANTS LEAD TO TETRAPLOID CELLS IN

  3. Failure Modes and Causes for Swing and Lift Type Check Valves

    Office of Scientific and Technical Information (OSTI)

    Group (NIC), ORNL has reviewed and analyzed check valve failures from the Institute of Nuclear Power Operations' (INPOs') Nuclear Plant Reliability Database System (NPRDS)...

  4. Abstract: Transactions and recoverable memories are pow-erful mechanisms for handling failures and manipulating

    E-Print Network [OSTI]

    Chen, Peter M.

    [Chen96]. Combined with an uninterruptible power supply, Rio provides persistent memory to applications]. Transactions are acclaimed widely as a powerful mechanism for handling failures. Transactions simplify pro

  5. Composite Materials for Hazard Mitigation of Reactive Metal Hydrides.

    SciTech Connect (OSTI)

    Pratt, Joseph William; Cordaro, Joseph Gabriel; Sartor, George B.; Dedrick, Daniel E.; Reeder, Craig L.

    2012-02-01

    In an attempt to mitigate the hazards associated with storing large quantities of reactive metal hydrides, polymer composite materials were synthesized and tested under simulated usage and accident conditions. The composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride. Composites with vinyl-containing siloxane oligomers were also polymerized with and without added styrene and divinyl benzene. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride reduced the inherent hydrogen storage capacity of the material. The composites were found to be initially effective at reducing the amount of heat released during oxidation. However, upon cycling the composites, the mitigating behavior was lost. While the polymer composites we investigated have mitigating potential and are physically robust, they undergo a chemical change upon cycling that makes them subsequently ineffective at mitigating heat release upon oxidation of the metal hydride. Acknowledgements The authors would like to thank the following people who participated in this project: Ned Stetson (U.S. Department of Energy) for sponsorship and support of the project. Ken Stewart (Sandia) for building the flow-through calorimeter and cycling test stations. Isidro Ruvalcaba, Jr. (Sandia) for qualitative experiments on the interaction of sodium alanate with water. Terry Johnson (Sandia) for sharing his expertise and knowledge of metal hydrides, and sodium alanate in particular. Marcina Moreno (Sandia) for programmatic assistance. John Khalil (United Technologies Research Corp) for insight into the hazards of reactive metal hydrides and real-world accident scenario experiments. Summary In an attempt to mitigate and/or manage hazards associated with storing bulk quantities of reactive metal hydrides, polymer composite materials (a mixture of a mitigating polymer and a metal hydride) were synthesized and tested under simulated usage and accident conditions. Mitigating the hazards associated with reactive metal hydrides during an accident while finding a way to keep the original capability of the active material intact during normal use has been the focus of this work. These composites were made by polymerizing vinyl monomers using free-radical polymerization chemistry, in the presence of the metal hydride, in this case a prepared sodium alanate (chosen as a representative reactive metal hydride). It was found that the polymerization of styrene and divinyl benzene could be initiated using AIBN in toluene at 70 degC. The resulting composite materials can be either hard or brittle solids depending on the cross-linking density. Thermal decomposition of these styrene-based composite materials is lower than neat polystyrene indicating that the chemical nature of the polymer is affected by the formation of the composite. The char-forming nature of cross-linked polystyrene is low and therefore, not an ideal polymer for hazard mitigation. To obtain composite materials containing a polymer with higher char-forming potential, siloxane-based monomers were investigated. Four vinyl-containing siloxane oligomers were polymerized with and without added styrene and divinyl benzene. Like the styrene materials, these composite materials exhibited thermal decomposition behavior significantly different than the neat polymers. Specifically, the thermal decomposition temperature was shifted approximately 100 degC lower than the neat polymer signifying a major chemical change to the polymer network. Thermal analysis of the cycled samples was performed on the siloxane-based composite materials. It was found that after 30 cycles the siloxane-containing polymer composite material has similar TGA/DSC-MS traces as the virgin composite material indicating that the polymer is physically intact upon cycling. Hydrogen capacity measurements revealed that addition of the polymer to the metal hydride in the form of a composite material reduced the inherent hydrogen storage capacity of the material. This

  6. Constitutive Model for Material Comminuting at High Shear Rate

    E-Print Network [OSTI]

    Zdenek P. Bazant; Ferhun C. Caner

    2013-06-04

    The modeling of high velocity impact into brittle or quasibrittle solids is hampered by the unavailability of a constitutive model capturing the effects of material comminution into very fine particles. The present objective is to develop such a model, usable in finite element programs. The comminution at very high strain rates can dissipate a large portion of the kinetic energy of an impacting missile. The spatial derivative of the energy dissipated by comminution gives a force resisting the penetration, which is superposed on the nodal forces obtained from the static constitutive model in a finite element program. The present theory is inspired partly by Grady's model for comminution due to explosion inside a hollow sphere, and partly by analogy with turbulence. In high velocity turbulent flow, the energy dissipation rate is enhanced by the formation of micro-vortices (eddies) which dissipate energy by viscous shear stress. Similarly, here it is assumed that the energy dissipation at fast deformation of a confined solid gets enhanced by the release of kinetic energy of the motion associated with a high-rate shear strain of forming particles. For simplicity, the shape of these particles in the plane of maximum shear rate is considered to be regular hexagons. The rate of release of free energy density consisting of the sum of this energy and the fracture energy of the interface between the forming particle is minimized. The particle sizes are assumed to be distributed according to Schuhmann's power law. It is concluded that the minimum particle size is inversely proportional to the (2/3)-power of the shear strain rate, that the kinetic energy release is to proportional to the (2/3)-power, and that the dynamic comminution creates an apparent material viscosity inversely proportional to the (1/3)-power of the shear strain rate.

  7. Interval to Biochemical Failure Highly Prognostic for Distant Metastasis and Prostate Cancer-Specific Mortality After Radiotherapy

    SciTech Connect (OSTI)

    Buyyounouski, Mark K. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)], E-mail: mark.buyyounouski@fccc.edu; Hanlon, Alexandra L.; Horwitz, Eric M.; Pollack, Alan [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

    2008-01-01

    Purpose: Few biochemical parameters have been related to mortality. The present study examined the clinical utility of the interval to biochemical failure (IBF) as a prognostic factor for distant metastasis (DM) and prostate cancer-specific mortality (PCSM) after radiotherapy. Methods and Materials: The study group consisted of 211 T1c-T3Nx-N0M0 patients who had experienced BF among 1,174 men treated with three-dimensional conformal radiotherapy alone. Biochemical failure was defined as a post-treatment prostate-specific antigen (PSA) level of at, or greater than, the PSA nadir plus 2 ng/mL. Cox proportional hazards modeling was used to identify independent predictors of DM and PCSM on multivariate analysis. Results: An IBF of <18 months was independently predictive for DM (p = 0.008), as was a Gleason score of 7-10 (p = 0.0005), PSA nadir {>=}2 ng/mL (p = 0.04), and decreasing radiation dose (p = 0.02) on multivariate analysis, including increasing pretreatment PSA level, PSA nadir {>=}2.5 ng/mL, PSA doubling time of <3 months, and Stage T3 disease. An IBF of <18 months was the only predictor of PCSM (p = 0.0003) in the same model. The actuarial 5-year DM rate for an IBF of <18 vs. {>=}18 months was 52% vs. 20% (p < 0.0001), and the actuarial PCSM rate was 36% vs. 6%, respectively (p = 0.0001). Conclusions: The IBF is an important descriptor of the PSA kinetics after radiotherapy to identify men at high risk of clinical failure and death. A IBF of <18 months could aid in selecting men for early, aggressive salvage therapy or participation in a clinical trial.

  8. Modeling Freedom From Progression for Standard-Risk Medulloblastoma: A Mathematical Tumor Control Model With Multiple Modes of Failure

    SciTech Connect (OSTI)

    Brodin, N. Patrik, E-mail: nils.patrik.brodin@rh.dk [Radiation Medicine Research Center, Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Niels Bohr Institute, University of Copenhagen, Copenhagen (Denmark); Vogelius, Ivan R. [Radiation Medicine Research Center, Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Björk-Eriksson, Thomas [Department of Oncology, Skåne University Hospital and Lund University, Lund (Sweden); Munck af Rosenschöld, Per [Radiation Medicine Research Center, Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Niels Bohr Institute, University of Copenhagen, Copenhagen (Denmark); Bentzen, Søren M. [Radiation Medicine Research Center, Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Department of Human Oncology, University of Wisconsin Medical School, Madison, Wisconsin (United States)

    2013-10-01

    Purpose: As pediatric medulloblastoma (MB) is a relatively rare disease, it is important to extract the maximum information from trials and cohort studies. Here, a framework was developed for modeling tumor control with multiple modes of failure and time-to-progression for standard-risk MB, using published pattern of failure data. Methods and Materials: Outcome data for standard-risk MB published after 1990 with pattern of relapse information were used to fit a tumor control dose-response model addressing failures in both the high-dose boost volume and the elective craniospinal volume. Estimates of 5-year event-free survival from 2 large randomized MB trials were used to model the time-to-progression distribution. Uncertainty in freedom from progression (FFP) was estimated by Monte Carlo sampling over the statistical uncertainty in input data. Results: The estimated 5-year FFP (95% confidence intervals [CI]) for craniospinal doses of 15, 18, 24, and 36 Gy while maintaining 54 Gy to the posterior fossa was 77% (95% CI, 70%-81%), 78% (95% CI, 73%-81%), 79% (95% CI, 76%-82%), and 80% (95% CI, 77%-84%) respectively. The uncertainty in FFP was considerably larger for craniospinal doses below 18 Gy, reflecting the lack of data in the lower dose range. Conclusions: Estimates of tumor control and time-to-progression for standard-risk MB provides a data-driven setting for hypothesis generation or power calculations for prospective trials, taking the uncertainties into account. The presented methods can also be applied to incorporate further risk-stratification for example based on molecular biomarkers, when the necessary data become available.

  9. JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES Vol. 3, No. 7, 2008

    E-Print Network [OSTI]

    Wadley, Haydn

    materials, composites, microbuckling, honeycomb, carbon fiber, carbon fibre. 1315 #12;1316 BENJAMIN P. WADLEY Carbon fibre epoxy matrix composite honeycombs have been fabricated by slotting, assembling the honeycombs failed by either elastic buckling or plastic microbuckling while in shear the two main failure

  10. Testing and Analysis of Low Cost Composite Materials Under Spectrum Loading and High Cycle Fatigue Conditions

    E-Print Network [OSTI]

    papers cited are available through the Sandia National Laboratories website: www.sandia.gov/Renewable_Energy/wind_energy-year experimental study of low- cost composite materials for wind turbine blades. Wind turbines are subjected to 109 in and potential interactions between failure modes. Wind turbine design codes typically assume a Miner's rule

  11. Monomer-Capped Tin Metal Nanoparticles for Anode Materials in Lithium Secondary Batteries

    E-Print Network [OSTI]

    Cho, Jaephil

    Monomer-Capped Tin Metal Nanoparticles for Anode Materials in Lithium Secondary Batteries Mijung Graphite can store 372 mAh/g corresponding to LiC6, and tin can store 970 mAh/g corresponding to Li4.4Sn close to graphite. The reason for failure is believed to be the inhomogeneous volume expansion

  12. Nondestructive material characterization

    DOE Patents [OSTI]

    Deason, Vance A. (Idaho Falls, ID); Johnson, John A. (Idaho Falls, ID); Telschow, Kenneth L. (Idaho Falls, ID)

    1991-01-01

    A method and apparatus for nondestructive material characterization, such as identification of material flaws or defects, material thickness or uniformity and material properties such as acoustic velocity. The apparatus comprises a pulsed laser used to excite a piezoelectric (PZ) transducer, which sends acoustic waves through an acoustic coupling medium to the test material. The acoustic wave is absorbed and thereafter reflected by the test material, whereupon it impinges on the PZ transducer. The PZ transducer converts the acoustic wave to electrical impulses, which are conveyed to a monitor.

  13. A Solid breeder tokamak blanket designed for failure mode operation

    E-Print Network [OSTI]

    Chen, Franklin Fun Kun

    1977-01-01

    The objective of this study was to evaluate a new concept for a Tokamak type fusion reactor blanket. The design was based on using a packed bed of lithium aluminate as the breeding material with helium gas cooling. The ...

  14. Colloquium: Failure of molecules, bones, and the Earth itself

    E-Print Network [OSTI]

    Buehler, Markus J.

    Materials fail by recurring rupture and shearing of interatomic bonds at microscopic, molecular scales, leading to disintegration of matter at macroscale and a loss of function. In this Colloquium, the state-of-the-art of ...

  15. Lengthscale effects in the damage and failure of composites

    E-Print Network [OSTI]

    Chambers, Jeffrey Thomas

    2014-01-01

    The primary objective of this work is to investigate and identify lengthscale effects associated with damage in composite materials and their structures, and to determine how these lengthscales vary across levels of ...

  16. EC Transmission Line Materials

    SciTech Connect (OSTI)

    Bigelow, Tim S

    2012-05-01

    The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.

  17. Earth-Abundant Materials

    Broader source: Energy.gov [DOE]

    DOE funds research into Earth-abundant materials for thin-film solar applications in response to the issue of materials scarcity surrounding other photovoltaic (PV) technologies. The sections below...

  18. Factors of material consumption

    E-Print Network [OSTI]

    Silva Díaz, Pamela Cristina

    2012-01-01

    Historic consumption trends for materials have been studied by many researchers, and, in order to identify the main drivers of consumption, special attention has been given to material intensity, which is the consumption ...

  19. Materials Science & Engineering

    E-Print Network [OSTI]

    and Forensics team in the Polymers and Coatings Group, MST-7. He graduated from the University of Toledo, aerogels, carbon fiber composites, damaged materials, and low density materials examining defects

  20. CRITICAL MATERIALS INSTITUTE PROJECTS

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

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

  1. Nanostructured composite reinforced material

    DOE Patents [OSTI]

    Seals, Roland D. (Oak Ridge, TN); Ripley, Edward B. (Knoxville, TN); Ludtka, Gerard M. (Oak Ridge, TN)

    2012-07-31

    A family of materials wherein nanostructures and/or nanotubes are incorporated into a multi-component material arrangement, such as a metallic or ceramic alloy or composite/aggregate, producing a new material or metallic/ceramic alloy. The new material has significantly increased strength, up to several thousands of times normal and perhaps substantially more, as well as significantly decreased weight. The new materials may be manufactured into a component where the nanostructure or nanostructure reinforcement is incorporated into the bulk and/or matrix material, or as a coating where the nanostructure or nanostructure reinforcement is incorporated into the coating or surface of a "normal" substrate material. The nanostructures are incorporated into the material structure either randomly or aligned, within grains, or along or across grain boundaries.

  2. Nanocomposites as thermoelectric materials

    E-Print Network [OSTI]

    Hao, Qing

    2010-01-01

    Thermoelectric materials have attractive applications in electric power generation and solid-state cooling. The performance of a thermoelectric device depends on the dimensionless figure of merit (ZT) of the material, ...

  3. Karankawa linguistic Materials

    E-Print Network [OSTI]

    Grant, Anthony P.

    1994-01-01

    In this paper I present the available materials on the diverse dialectal forms of the extinct Karankawa language of coastal Texas in the form of an English-Karankawa vocabulary, together with the attested sentence and text material, a transcription...

  4. Radioactive Materials Product Stewardship

    E-Print Network [OSTI]

    Radioactive Materials Product Stewardship ABackground Report for the National Dialogue...................................................................................................26 Low Level Waste (LLW) Disposal Regulations on Radioactive Materials Product Stewardship Prepared by the: Product Stewardship Institute University

  5. Geopolymer Sealing Materials

    Broader source: Energy.gov [DOE]

    DOE Geothermal Peer Review 2010 - Presentation. Project objectives: Develop and characterize field-applicable geopolymer temporary sealing materials in the laboratory and to transfer this developed material technology to geothermal drilling service companies as collaborators for field validation tests.

  6. Three-dimensional geomechanical simulation of reservoir compaction and implications for well failures in the Belridge diatomite

    SciTech Connect (OSTI)

    Fredrich, J.T. [SPE, Richardson, TX (United States); Argueello, J.G.; Thorne, B.J.; Wawersik, W.R. [SPE, Richardson, TX (United States)]|[Sandia National Lab., Albuquerque, NM (United States)] [and others

    1996-11-01

    This paper describes an integrated geomechanics analysis of well casing damage induced by compaction of the diatomite reservoir at the Belridge Field, California. Historical data from the five field operators were compiled and analyzed to determine correlations between production, injection, subsidence, and well failures. The results of this analysis were used to develop a three-dimensional geomechanical model of South Belridge, Section 33 to examine the diatomite reservoir and overburden response to production and injection at the interwell scale and to evaluate potential well failure mechanisms. The time-dependent reservoir pressure field was derived from a three-dimensional finite difference reservoir simulation and used as input to three-dimensional non-linear finite element geomechanical simulations. The reservoir simulation included -200 wells and covered 18 years of production and injection. The geomechanical simulation contained 437,100 nodes and 374,130 elements with the overburden and reservoir discretized into 13 layers with independent material properties. The results reveal the evolution of the subsurface stress and displacement fields with production and injection and suggest strategies for reducing the occurrence of well casing damage.

  7. Measuring Time to Biochemical Failure in the TROG 96.01 Trial: When Should the Clock Start Ticking?

    SciTech Connect (OSTI)

    Denham, James W.; Steigler, Allison; Kumar, Mahesh; Lamb, David S.; Joseph, David; Spry, Nigel A.; Tai, Keen-Hun; Atkinson, Chris; Turner, Sandra FRANZCR; Greer, Peter B.; Gleeson, Paul S.; D'Este, Catherine

    2009-11-15

    Purpose: We sought to determine whether short-term neoadjuvant androgen deprivation (STAD) duration influences the optimal time point from which Phoenix fail (time to biochemical failure; TTBF) should be measured. Methods and Materials: In the Trans-Tasman Radiation Oncology Group 96.01 trial, men with locally advanced prostate cancer were randomized to 3 or 6 months STAD before and during prostatic irradiation (XRT) or to XRT alone. The prognostic value of TTBF measured from the end of radiation (ERT) and randomization were compared using Cox models. Results: Between 1996 and 2000, 802 eligible patients were randomized. In 436 men with Phoenix failure, TTBF measured from randomization was a powerful predictor of prostate cancer-specific survival and marginally more accurate than TTBF measured from ERT in Cox models. Insufficient data were available to confirm that TTBF measured from testosterone recovery may also be a suitable option. Conclusions: TTBF measured from randomization (commencement of therapy) performed well in this trial dataset and will be a convenient option if this finding holds in other datasets that include long-term androgen deprivation data.

  8. VHTR Materials Overview

    SciTech Connect (OSTI)

    Wright, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-07-30

    The PowerPoint presentation was given at the DOE-NE Materials Crosscut Coordination Meeting, Tuesday, 30 July 2013.

  9. UNCLASSIFIED Institute for Materials ...

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

    Garritt Tucker Drexel University, Philadelphia, Pennsylvania Atomistic Methods to Quantify Nanoscale Strain and Deformation Mechanisms in Nanostructured Materials Thursday, August...

  10. HIGH PERFORMANCE MACROMOLECULAR MATERIALS

    E-Print Network [OSTI]

    M. Gregory Forest. Department of Mathematics. Institute for Advanced Materials, Nanoscience & Technology. University of North Carolina at Chapel Hill.

  11. Instructions and Materials

    Broader source: Energy.gov [DOE]

    The following are 2012 Program Peer Review Meeting instructions, materials and resource links for presenters and reviewers.

  12. Materials Science & Engineering

    E-Print Network [OSTI]

    Materials Science & Engineering New paradigms in the R&D of novel multifunctional oxide and nanocarbon thin films are providing the bases for new physics, new materials science and chemistry Laboratory (ANL) during the past fifteen years. Also, the applications of these materials for a new

  13. Advanced neutron absorber materials

    DOE Patents [OSTI]

    Branagan, Daniel J. (Idaho Falls, ID); Smolik, Galen R. (Idaho Falls, ID)

    2000-01-01

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  14. Esselen Linguistic Materials

    E-Print Network [OSTI]

    Shaul, David L.; Turner, Katherine; Collins, James D.

    1984-01-01

    The primary purpose of this paper is to make a complete list of materials known on the Esselen language available in a single place. The existing lexical material has been organized into a lexicon which is followed by phrasal and sentence materials...

  15. Materials Science & Engineering

    E-Print Network [OSTI]

    Simons, Jack

    Materials Science & Engineering The University of Utah 2014-15 Undergraduate Handbook #12;STUDYING FOR A MATERIALS SCIENCE AND ENGINEERING DEGREE Materials Science and Engineering inter-twines numerous disciplines, including chemistry, physics and engineering. It is the one discipline within the College of Engineering

  16. Investigating Deformation and Failure Mechanisms in Nanoscale Multilayer Metallic Composites

    SciTech Connect (OSTI)

    Zbib, Hussein M; Bahr, David F

    2014-10-22

    Over the history of materials science there are many examples of materials discoveries that have made superlative materials; the strongest, lightest, or toughest material is almost always a goal when we invent new materials. However, often these have been a result of enormous trial and error approaches. A new methodology, one in which researchers design, from the atoms up, new ultra-strong materials for use in energy applications, is taking hold within the science and engineering community. This project focused on one particular new classification of materials; nanolaminate metallic composites. These materials, where two metallic materials are intimately bonded and layered over and over to form sheets or coatings, have been shown over the past decade to reach strengths over 10 times that of their constituents. However, they are not yet widely used in part because while extremely strong (they don’t permanently bend), they are also not particularly tough (they break relatively easily when notched). Our program took a coupled approach to investigating new materials systems within the laminate field. We used computational materials science to explore ways to institute new deformation mechanisms that occurred when a tri-layer, rather than the more common bi-layer system was created. Our predictions suggested that copper-nickel or copper-niobium composites (two very common bi-layer systems) with layer thicknesses on the order of 20 nm and then layered 100’s of times, would be less tough than a copper-nickel-niobium metallic composite of similar thicknesses. In particular, a particular mode of permanent deformation, cross-slip, could be activated only in the tri-layer system; the crystal structure of the other bi-layers would prohibit this particular mode of deformation. We then experimentally validated this predication using a wide range of tools. We utilized a DOE user facility, the Center for Integrated Nanotechnology (CINT), to fabricate, for the first time, these tri-layer composites. CINT formed nanolaminate composites were tested in tension, with bulge testing, using nanoindentation, and using micro-compression testing to demonstrate that the tri-layer films were indeed tougher and hardened more during deformation (they got stronger as we deformed them) than equivalent bi-layers. The seven graduate students, 4 post-docs and research faculty, and the two faculty co-PI’s were able to create a collaborated computational prediction and experimental validation team to demonstrate the benefits of this class of materials to the community. The computational work crossed from atomistic to bulk simulations, and the experiments coupled form nm-scale to the mm scale; closely matching the simulations. The simulations provided viable mechanisms that explained the observed results, and new experimental results were used to push the boundaries of the simulation tools. Over the life of the 7 years of this program we proved that tri-layer nanolaminate metallic composite systems exceeded the mechanical performance of bi-layer systems if the right materials were chosen, and that the mechanism responsible for this was tied to the cross slip of dislocations. With 30 journal publications resulting from this work we have broadly disseminated this family of results to the scientific community.

  17. Defining biochemical failure after radiotherapy with and without androgen deprivation for prostate cancer

    SciTech Connect (OSTI)

    Buyyounouski, Mark K. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)]. E-mail: mark.buyyounouski@fccc.edu; Hanlon, Alexandra L. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Eisenberg, Debra F. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Horwitz, Eric M. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Feigenberg, Steven J. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Uzzo, Robert G. [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Pollack, Alan [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

    2005-12-01

    Purpose: To compare several characteristics of alternative definitions of biochemical failure (BF) in men with extended follow-up after radiotherapy (RT) with or with androgen deprivation therapy (ADT) for prostate cancer. Methods and Materials: From December 1, 1991, to April 30, 1998, 688 men with Stage T1c-T3NX-N0M0 prostate cancer received RT alone (n = 586) or RT plus ADT (n = 102) with a minimal follow-up of 4 years and five or more 'ADT-free' posttreatment prostate-specific antigen levels. BF was defined by three methods: (1) the ASTRO definition (three consecutive rises in prostate-specific antigen level); (2) a modified American Society for Therapeutic Radiology Oncology (ASTRO) definition requiring two additional consecutive rises when a decline immediately subsequent to three consecutive rises occurred; and (3) the 'Houston' or nadir plus 2-ng/mL definition (a rise of at least 2 ng/mL greater than the nadir). The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were determined for each using clinical progression as the endpoint. Furthermore, the misclassification rates for a steadily rising prostate-specific antigen level, ability to satisfy the proportional hazards (RT with or without ADT), effects of short follow-up, and intervals to the diagnosis of BF were compared. Results: The misclassification rate for BF using the nadir plus 2-ng/mL definition was 2% for RT alone and 0% for RT plus ADT compared with 0% and 0% for the modified ASTRO definition, and 5% and 23% for the ASTRO definition, respectively. The hazard rates for RT alone and RT plus ADT were proportional only for the nadir plus 2 ng/mL definition and seemingly unaffected by the length of follow-up. For RT with or without ADT, the nadir plus 2 ng/mL definition was the most specific (RT, 80% vs. RT plus ADT, 75%) with the greatest positive predictive value (RT, 36% vs. RT plus ADT, 25%) and overall accuracy (RT, 81% vs. RT plus ADT, 77%). A greater proportion of BF was diagnosed in the first 2 years of follow-up with the nadir plus 2 ng/mL definition compared with the ASTRO definition (13% vs. 5%, p = 0.0138, chi-square test). Conclusion: The nadir plus 2 ng/mL definition was the best predictor of sustained, true, biochemical, and clinical failure, and was not affected by the use of ADT or follow-up length.

  18. Material review of Li ion battery separators

    SciTech Connect (OSTI)

    Weber, Christoph J., E-mail: Christoph.Weber@freudenberg-nw.com; Geiger, Sigrid, E-mail: Christoph.Weber@freudenberg-nw.com [Freudenberg Vliesstoffe SE and Co KG, 69465 Weinheim (Germany); Falusi, Sandra; Roth, Michael [Freudenberg Forschungsdienste SE and Co KG, 69465 Weinheim (Germany)

    2014-06-16

    Separators for Li Ion batteries have a strong impact on cell production, cell performance, life, as well as reliability and safety. The separator market volume is about 500 million m{sup 2} mainly based on consumer applications. It is expected to grow strongly over the next decade for mobile and stationary applications using large cells. At present, the market is essentially served by polyolefine membranes. Such membranes have some technological limitations, such as wettability, porosity, penetration resistance, shrinkage and meltdown. The development of a cell failure due to internal short circuit is potentially closely related to separator material properties. Consequently, advanced separators became an intense area of worldwide research and development activity in academia and industry. New separator technologies are being developed especially to address safety and reliability related property improvements.

  19. A Novel Risk Stratification to Predict Local-Regional Failures in Urothelial Carcinoma of the Bladder After Radical Cystectomy

    SciTech Connect (OSTI)

    Baumann, Brian C.; Guzzo, Thomas J.; He Jiwei; Keefe, Stephen M.; Tucker, Kai; Bekelman, Justin E.; Hwang, Wei-Ting; Vaughn, David J.; Malkowicz, S. Bruce; Christodouleas, John P.

    2013-01-01

    Purpose: Local-regional failures (LF) following radical cystectomy (RC) plus pelvic lymph node dissection (PLND) with or without chemotherapy for invasive urothelial bladder carcinoma are more common than previously reported. Adjuvant radiation therapy (RT) could reduce LF but currently has no defined role because of previously reported morbidity. Modern techniques with improved normal tissue sparing have rekindled interest in RT. We assessed the risk of LF and determined those factors that predict recurrence to facilitate patient selection for future adjuvant RT trials. Methods and Materials: From 1990-2008, 442 patients with urothelial bladder carcinoma at University of Pennsylvania were prospectively followed after RC plus PLND with or without chemotherapy with routine pelvic computed tomography (CT) or magnetic resonance imaging (MRI). One hundred thirty (29%) patients received chemotherapy. LF was any pelvic failure detected before or within 3 months of distant failure. Competing risk analyses identified factors predicting increased LF risk. Results: On univariate analysis, pathologic stage {>=}pT3, <10 nodes removed, positive margins, positive nodes, hydronephrosis, lymphovascular invasion, and mixed histology significantly predicted LF; node density was marginally predictive, but use of chemotherapy, number of positive nodes, type of surgical diversion, age, gender, race, smoking history, and body mass index were not. On multivariate analysis, only stage {>=}pT3 and <10 nodes removed were significant independent LF predictors with hazard ratios of 3.17 and 2.37, respectively (P<.01). Analysis identified 3 patient subgroups with significantly different LF risks: low-risk ({<=}pT2), intermediate-risk ({>=}pT3 and {>=}10 nodes removed), and high-risk ({>=}pT3 and <10 nodes) with 5-year LF rates of 8%, 23%, and 42%, respectively (P<.01). Conclusions: This series using routine CT and MRI surveillance to detect LF confirms that such failures are relatively common in cases of locally advanced disease and provides a rubric based on pathological stage and number of nodes removed that stratifies patients into 3 groups with significantly different LF risks to simplify patient selection for future adjuvant radiation therapy trials.

  20. Predicting crack growth in continuous-fiber composite materials

    SciTech Connect (OSTI)

    Cordes, J.A.; Yazici, R.

    1995-12-31

    Pre-notched composite lamina with unidirectional fibers were studied experimentally and using finite element analysis. Experiments were conducted on notched graphite/aluminum and glass/epoxy panels and the results were compared to a finite element method. Under remote tensile loading, cracks in the graphite/aluminum panels propagated perpendicular to the applied load without stable crack growth. In the glass/epoxy panels, crack propagation was initially stable and parallel to the fibers. A nonlinear damage zone method (DZM) was used to predict the crack growth directions, estimate damages, model stable and unstable crack growths, and predict the loads at failure. For both materials, the predicted loads at failure were within 20% of experimental loads.

  1. Datacenter Scale Evaluation of the Impact of Temperature on Hard Disk Drive Failures

    E-Print Network [OSTI]

    Gurumurthi, Sudhanva

    Datacenter Scale Evaluation of the Impact of Temperature on Hard Disk Drive Failures SRIRAM SANKAR rely heavily on their datacenters to serve end users. A large datacenter facility incurs increased, there is very little understanding on the major determinants of disk failures in datacenters. In this work, we

  2. Affective Agents: Sustaining Motivation to Learn Through Failure and a State of "Stuck"

    E-Print Network [OSTI]

    Affective Agents: Sustaining Motivation to Learn Through Failure and a State of "Stuck" Winslow to persevere and remain motivated through failure. Many researchers creating ITSs have taken the approach' motivation. There are numerous circumstances where this approach is impractical, undesirable, or simply

  3. Al.SEP Array E -Comm~nd Decoder Failure Modes, Effects 8;

    E-Print Network [OSTI]

    Rathbun, Julie A.

    in the Control Logic Section by locking to the 1 KHz uplink clock generated at the ground station. The phase lock\\ Al.SEP Array E - Comm~nd Decoder Failure Modes, Effects 8; ATM 949 ! Criticality Analysis PAGI OF 27 DATE 6-1-71 This ATM dotuments the Failure Modes, Effects and Criticality Analysis 'on the Bendix

  4. On-Line Learning Failure-Tolerant Neural-Aided Controller for Earthquake Excited Structures

    E-Print Network [OSTI]

    Nagarajaiah, Satish

    On-Line Learning Failure-Tolerant Neural-Aided Controller for Earthquake Excited Structures Sriram Abstract: This paper presents an on-line learning failure-tolerant neural controller capable of controlling buildings subjected to severe earthquake ground motions. In the proposed scheme the neural controller aids

  5. On Impedance Spectroscopy Contribution to Failure Diagnosis in Wind Turbine Generators

    E-Print Network [OSTI]

    Boyer, Edmond

    On Impedance Spectroscopy Contribution to Failure Diagnosis in Wind Turbine Generators Mohamed Becherif1 , El Houssin El Bouchikhi2 and Mohamed Benbouzid2 Abstract ­ Wind turbines proliferation impedance spectroscopy contribution to the failure diagnosis of doubly-fed induction generator-based wind

  6. Failure Mechanisms in Pipelines Bridging a Void J. G. Zornberg1

    E-Print Network [OSTI]

    Zornberg, Jorge G.

    Failure Mechanisms in Pipelines Bridging a Void J. G. Zornberg1 , Y.D. Costa2 , and B.S. Bueno3 1 program is being conducted to evaluate the failure mechanisms of pipelines subjected to a localized loss will allow the design of reinforced soil systems suitable to mitigate damage in pipelines. The experimental

  7. SPECTRAL BASED METHODS THAT STREAMLINE THE SEARCH FOR FAILURE SCENARIOS IN LARGE-SCALE DISTRIBUTED SYSTEMS

    E-Print Network [OSTI]

    the detection of failure sce- narios in distributed grid computing, cloud computing and other large scale performance deteriorates and fails. KEY WORDS grid computing, cloud computing, failure, spectral expan- sion systems such as computing grids and commercial cloud systems has made mass computing services available

  8. Dynamic monitoring of spectral components for automatic detection of failures in wind farms

    E-Print Network [OSTI]

    Dobigeon, Nicolas

    Dynamic monitoring of spectral components for automatic detection of failures in wind farms Master The energy produced by wind farm is becoming more and more important worldwide. Its impact on the electrical) characterize the presence of failures. Subject In wind turbines, signals are regularly acquired

  9. A Methodology for Weapon System Availability Assessment, incorporating Failure, Damage and

    E-Print Network [OSTI]

    Boyer, Edmond

    A Methodology for Weapon System Availability Assessment, incorporating Failure, Damage systems can become unavailable due to system failures or damage to the system; in both cases, system the more specific availability studies take battlefield damage into account. This paper aims to define

  10. Error-in-variables for failure criteria applied to the near -wellbore region 

    E-Print Network [OSTI]

    Zambrano, Orlando

    2004-09-30

    the experimental data are used directly to determine the failure envelope in the Mohr plane. When a failure envelope is first obtained in the principal-stress plane and then transformed into the Mohr plane using Computer Algebra. When the presence of pore fluid...

  11. An Automatic Failure Mode and Effect Analysis Technique for Processes Defined in the Little-JIL

    E-Print Network [OSTI]

    Avrunin, George S.

    Failure Mode and Effect Analysis (FMEA) information from processes modeled in the Little-JIL process definition language. Typically FMEA information is created manually by skilled experts, an approach this definition can then be used to create FMEA representations for a wide range of potential failures

  12. Failure of Carbon Fibers at a Crease in a Fiber-Reinforced Silicone Sheet

    E-Print Network [OSTI]

    Pellegrino, Sergio

    -based Weibull modulus of tensile failure mB Weibull modulus of bending failure M bending moment n number of 1 mm decrease the maximum strain in the fibers near the compression surface. This paper shows's modulus Et tensile Young's modulus of fiber Ec compressive Young's modulus of fiber F end force on looped

  13. Failure Mode and Effect Analysis of Concrete Ties in orth America

    E-Print Network [OSTI]

    Barkan, Christopher P.L.

    Engineering University of Illinois at Urbana-Champaign Summary: A failure mode and effect analysis (FMEA in systems and components is the Failure Mode and Effect Analysis (FMEA), and we are applying this approach of concrete ties to take full advantage of their potential. FMEA is an efficient procedure for organizing

  14. Signature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany

    E-Print Network [OSTI]

    Gilli, Adrian

    Signature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany 4 November 2003; received in revised form 12 April 2004; accepted 26 April 2004 Abstract Landslide-dammed that the hyperpycnite deposits are directly related to the failure of two sturzstrom dams and the draining of the dammed

  15. Inference for the dependent competing risks model with masked causes of failure

    E-Print Network [OSTI]

    Craiu, V. Radu

    Inference for the dependent competing risks model with masked causes of failure Radu V. Craiu Æ/fail for different reasons. The cause specific hazard rates are taken to be piecewise constant functions. A complication arises when some of the failures are masked within a group of possible causes. Traditionally

  16. Inference based on the em algorithm for the competing risk model with masked causes of failure

    E-Print Network [OSTI]

    Duchesne, Thierry

    Inference based on the em algorithm for the competing risk model with masked causes of failure parameterised competing risks model with masked causes of failure and second-stage data. With a carefully chosen definition of complete data, the maximum likelihood estimation of the cause-specific hazard functions

  17. Automated Support for Classifying Software Failure Reports Andy Podgurski, David Leon, Patrick Francis,

    E-Print Network [OSTI]

    Sun, Jiayang

    Automated Support for Classifying Software Failure Reports Andy Podgurski, David Leon, Patrick automated support for classifying reported software failures in order to facilitate prioritizing them of three large subject programs are reported. These results indicate that the strategy can be effective. 1

  18. Statistical Monitoring of Time-to-Failure Data Using Rank Tests

    E-Print Network [OSTI]

    Zhou, Shiyu

    statistics, we derived the generic formulae for the operating characteristic functions of the control chartStatistical Monitoring of Time-to-Failure Data Using Rank Tests Zhiguo Li,a * Shiyu Zhou,b Crispian of the fast development of information technology, the critical failure events and maintenance events

  19. Failure-Atomic msync(): A Simple and Efficient Mechanism for Preserving the Integrity of Durable Data

    E-Print Network [OSTI]

    Shen, Kai

    Failure-Atomic msync(): A Simple and Efficient Mechanism for Preserving the Integrity of Durable the integrity of application data across updates is difficult if power outages and system crashes may oc- cur- atomic msync() commits changes to a memory-mapped file atomically, even in the presence of failures. Our

  20. Failure recovery for structured p2p networks: Protocol design and performance under churn q

    E-Print Network [OSTI]

    Lam, Simon S.

    Failure recovery for structured p2p networks: Protocol design and performance under churn q Simon S,000 s of simulated time. In each such ``churn'' experiment, we took a ``snapshot'' of neighbor tables in the network of the churn rate, timeout value in failure recovery, and K. We found our protocols to be effective, efficient

  1. > REPLACE THIS LINE WITH YOUR PAPER IDENTIFICATION NUMBER (DOUBLE-CLICK HERE TO EDIT) failures in

    E-Print Network [OSTI]

    Hadjicostis, Christoforos

    -- This paper presents a method to identify failures in smart grids. The method is based on a carefully designed and allows the identification of failures by means of simple matrix operations over a suitably chosen, by enabling grid connection of Distributed Generation (DG), by incorporating grid energy storage for DG load

  2. Tsunami Generation by Submarine Mass Failure. I: Modeling, Experimental Validation, and Sensitivity Analyses

    E-Print Network [OSTI]

    Grilli, Stéphan T.

    Tsunami Generation by Submarine Mass Failure. I: Modeling, Experimental Validation, and Sensitivity with a two-dimensional 2D fully nonlinear potential flow FNPF model for tsunami generation by two idealized types of submarine mass failure SMF : underwater slides and slumps. These simulations feature rigid

  3. Multi-Layer Network Recovery: Avoiding Traffic Disruptions against Fiber Failures

    E-Print Network [OSTI]

    Ortega, Eusebi Calle

    Multi-Layer Network Recovery: Avoiding Traffic Disruptions against Fiber Failures Anna Urra, Eusebi 17071, Spain Abstract. The next generation backbone networks, optical IP/MPLS networks, enable increasingly higher volumes of information to be trans- ported. In this network architecture, a fiber failure

  4. Rosetta Predictions in CASP5: Successes, Failures, and Prospects for Complete Automation

    E-Print Network [OSTI]

    Baker, David

    Rosetta Predictions in CASP5: Successes, Failures, and Prospects for Complete Automation Philip insertions; we describe here the successes as well as the failures in the context of current efforts target sequence. To generate template-based models, we used homologous structure information; insertions

  5. Propagation failures, breathing pulses, and backfiring in an excitable reaction-diffusion system

    E-Print Network [OSTI]

    Steinbock, Oliver

    Propagation failures, breathing pulses, and backfiring in an excitable reaction-diffusion system pulses and pulse trains that can undergo complex sequences of propagation failures. Moreover, we present that near their back repeatedly generate new pulses propagating in opposite direction. © 2006 American

  6. Signatures of slope failures and river-delta collapses in a perialpine lake (Lake Lucerne, Switzerland)

    E-Print Network [OSTI]

    Gilli, Adrian

    Signatures of slope failures and river-delta collapses in a perialpine lake (Lake Lucerne) which caused extensive slope failures in many parts of the lake. The second event in AD 1687 signatures of the two subaqueous mass movements that probably generated the observed tsunamis. Such mass

  7. Tables for Trials and Failures with PD for Designated Confidence Level

    SciTech Connect (OSTI)

    Leach, Janice

    2014-02-01

    Two attachments are provided for performance testing of sensors and other Physical Protection System (PPS) components.#2; The first attachment is a table of Trials and Failures, giving Probability of Detection (PD) for a designated confidence level and sorted by trials.#2; The second attachment contains the same data, sorted by failures.

  8. Remote performance check and automated failure identification for grid-connected PV systems

    E-Print Network [OSTI]

    Heinemann, Detlev

    Remote performance check and automated failure identification for grid-connected PV systems cloudy skies. This determines the quality of the PV simulation and finally the period of time, satellite data, PVSAT-2 1. Introduction Failure-free operation of grid-connected photovoltaic (PV) systems

  9. Tailored Porous Materials

    SciTech Connect (OSTI)

    BARTON,THOMAS J.; BULL,LUCY M.; KLEMPERER,WALTER G.; LOY,DOUGLAS A.; MCENANEY,BRIAN; MISONO,MAKOTO; MONSON,PETER A.; PEZ,GUIDO; SCHERER,GEORGE W.; VARTULI,JAMES C.; YAGHI,OMAR M.

    1999-11-09

    Tailoring of porous materials involves not only chemical synthetic techniques for tailoring microscopic properties such as pore size, pore shape, pore connectivity, and pore surface reactivity, but also materials processing techniques for tailoring the meso- and the macroscopic properties of bulk materials in the form of fibers, thin films and monoliths. These issues are addressed in the context of five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol-gel derived oxides, and porous heteropolyanion salts. Reviews of these specific areas are preceded by a presentation of background material and review of current theoretical approaches to adsorption phenomena. A concluding section outlines current research needs and opportunities.

  10. Analyzing Cascading Failures in Smart Grids under Random and Targeted Attacks

    E-Print Network [OSTI]

    Ruj, Sushmita

    2015-01-01

    We model smart grids as complex interdependent networks, and study targeted attacks on smart grids for the first time. A smart grid consists of two networks: the power network and the communication network, interconnected by edges. Occurrence of failures (attacks) in one network triggers failures in the other network, and propagates in cascades across the networks. Such cascading failures can result in disintegration of either (or both) of the networks. Earlier works considered only random failures. In practical situations, an attacker is more likely to compromise nodes selectively. We study cascading failures in smart grids, where an attacker selectively compromises the nodes with probabilities proportional to their degrees; high degree nodes are compromised with higher probability. We mathematically analyze the sizes of the giant components of the networks under targeted attacks, and compare the results with the corresponding sizes under random attacks. We show that networks disintegrate faster for targeted...

  11. Determining the Cause of a Header Failure in a Natural Gas Production Facility

    SciTech Connect (OSTI)

    Matthes, S.A.; Covino, B.S., Jr.; Bullard, S.J.; Ziomek-Moroz, M.; Holcomb, G.R.

    2007-03-01

    An investigation was made into the premature failure of a gas-header at the Rocky Mountain Oilfield Testing Center (RMOTC) natural gas production facility. A wide variety of possible failure mechanisms were considered: design of the header, deviation from normal pipe alloy composition, physical orientation of the header, gas composition and flow rate, type of corrosion, protectiveness of the interior oxide film, time of wetness, and erosion-corrosion. The failed header was examined using metallographic techniques, scanning electron microscopy, and microanalysis. A comparison of the failure site and an analogous site that had not failed, but exhibited similar metal thinning was also performed. From these studies it was concluded that failure resulted from erosion-corrosion, and that design elements of the header and orientation with respect to gas flow contributed to the mass loss at the failure point.

  12. Identifying failure in a tree network of a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Pinnow, Kurt W. (Rochester, MN); Wallenfelt, Brian P. (Eden Prairie, MN)

    2010-08-24

    Methods, parallel computers, and products are provided for identifying failure in a tree network of a parallel computer. The parallel computer includes one or more processing sets including an I/O node and a plurality of compute nodes. For each processing set embodiments include selecting a set of test compute nodes, the test compute nodes being a subset of the compute nodes of the processing set; measuring the performance of the I/O node of the processing set; measuring the performance of the selected set of test compute nodes; calculating a current test value in dependence upon the measured performance of the I/O node of the processing set, the measured performance of the set of test compute nodes, and a predetermined value for I/O node performance; and comparing the current test value with a predetermined tree performance threshold. If the current test value is below the predetermined tree performance threshold, embodiments include selecting another set of test compute nodes. If the current test value is not below the predetermined tree performance threshold, embodiments include selecting from the test compute nodes one or more potential problem nodes and testing individually potential problem nodes and links to potential problem nodes.

  13. Tolerating Correlated Failures for Generalized Cartesian Distributions via Bipartite Matching

    SciTech Connect (OSTI)

    Ali, Nawab; Krishnamoorthy, Sriram; Halappanavar, Mahantesh; Daily, Jeffrey A.

    2011-05-05

    Faults are expected to play an increasingly important role in how algorithms and applications are designed to run on future extreme-scale systems. A key ingredient of any approach to fault tolerance is effective support for fault tolerant data storage. A typical application execution consists of phases in which certain data structures are modified while others are read-only. Often, read-only data structures constitute a large fraction of total memory consumed. Fault tolerance for read-only data can be ensured through the use of checksums or parities, without resorting to expensive in-memory duplication or checkpointing to secondary storage. In this paper, we present a graph-matching approach to compute and store parity data for read-only matrices that are compatible with fault tolerant linear algebra (FTLA). Typical approaches only support blocked data distributions with each process holding one block with the parity located on additional processes. The matrices are assumed to be blocked by a cartesian grid with each block assigned to a process. We consider a generalized distribution in which each process can be assigned arbitrary blocks. We also account for the fact that multiple processes might be part of the same failure unit, say an SMP node. The flexibility enabled by our novel application of graph matching extends fault tolerance support to data distributions beyond those supported by prior work. We evaluate the matching implementations and cost to compute the parity and recover lost data, demonstrating the low overhead incurred by our approach.

  14. Pipeline failure: The roles played by corrosion, flow and metallurgy

    SciTech Connect (OSTI)

    Paisley, D.; Barrett, N.; Wilson, O.

    1999-11-01

    Carbon dioxide corrosion has been widely studied in the field and laboratory. It is recognized that flow regime and metallurgy are important factors that influence in-situ corrosion rates but there are relatively few documented case studies that are able to separate the individual contributions of corrosion, flow regime and metallurgy on the observed corrosion damage. This paper deals with failure of a pipeline where high quality inspection data together with comprehensive as-built records and stable production conditions allowed the separate influences of flow and metallurgy on corrosion to be studied. The flow regimes in the pipeline ranged from low velocity, stratified flow to high velocity, slug flow. The inspection data showed that the affect of turbulent flow was to increase the frequency of corrosion pits and, in the case of weld corrosion, the mean corrosion rate. The pipeline was constructed from two grades of steel and welded using two types of welding consumable. One grade of pipeline steel corroded at a significantly higher rate and with a higher frequency of corrosion pits than another, apparently similar steel. However, no significant relationship was found between weld metallurgy and corrosion rate or frequency.

  15. FY 2009 Progress Report for Lightweighting Materials - 12. Materials...

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

    for Lightweighting Materials - 12. Materials Crosscutting Research and Development The primary Lightweight Materials activity goal is to validate a cost-effective weight reduction...

  16. A FUNCTIONALLY GRADED PARTICULATE COMPOSITE: PREPARATION, MEASUREMENTS AND FAILURE

    E-Print Network [OSTI]

    Rousseau, Carl-Ernst

    planes. Such materials have been developed using dierent processes including slip casting [1], centrifugal casting [2], laser alloying and cladding [3], and plasma-spray forming [4]. The FGMs pose new and examined crack growth resistance behavior using the rule of mixtures. Functionally graded metal/cer- a

  17. Nanotube fracture during the failure of carbon nanotube/ alumina composites

    E-Print Network [OSTI]

    -based ceramic composites, leading to improved fracture toughness. Ó 2011 Elsevier Ltd. All rights reserved. 1 problem, incorporation of particulates, flakes and short/long fibers into ceramics matrix, as a second, chemical and electrical properties [3­7], motivating their use in ceramic composite materials as a fibrous

  18. Thirty-ninth Hawaii International Conference on System Sciences, January 2006, Kauai, Hawaii. c 2006 IEEE An estimator of propagation of cascading failure

    E-Print Network [OSTI]

    on a saturating branching process model of cascading failure and on failure data generated by the OPA simulation 2006 IEEE An estimator of propagation of cascading failure Ian Dobson, Kevin R. Wierzbicki, Benjamin A the extent to which failures propagate in cascading failures such as large blackouts. The estimator is tested

  19. Module Design, Materials, and Packaging Research Team: Activities and Capabilities

    SciTech Connect (OSTI)

    McMahon, T. J.; del Cueto, J.; Glick, S.; Jorgensen, G.; Kempe, M.; Kennedy, C.; Pern, J.; Terwilliger, K

    2005-01-01

    Our team activities are directed at improving PV module reliability by incorporating new, more effective, and less expensive packaging materials and techniques. New and existing materials or designs are evaluated before and during accelerated environmental exposure for the following properties: (1) Adhesion and cohesion: peel strength and lap shear. (2) Electrical conductivity: surface, bulk, interface and transients. (3) Water vapor transmission: solubility and diffusivity. (4) Accelerated weathering: ultraviolet, temperature, and damp heat tests. (5) Module and cell failure diagnostics: infrared imaging, individual cell shunt characterization, coring. (6) Fabrication improvements: SiOxNy barrier coatings and enhanced wet adhesion. (7) Numerical modeling: Moisture ingress/egress, module and cell performance, and cell-to-frame leakage current. (8) Rheological properties of polymer encapsulant and sheeting materials. Specific examples will be described.

  20. Thermal Performance and Reliability Characterization of Bonded Interface Materials (BIMs): Preprint

    SciTech Connect (OSTI)

    DeVoto, D.; Paret, P.; Mihalic, M.; Narumanchi, S.; Bar-Cohen, A.; Matin, K.

    2014-08-01

    Thermal interface materials are an important enabler for low thermal resistance and reliable electronics packaging for a wide array of applications. There is a trend towards bonded interface materials (BIMs) because of their potential for low thermal resistivity (< 1 mm2K/W). However, BIMs induce thermomechanical stresses in the package and can be prone to failures and integrity risks. Deteriorated interfaces can result in high thermal resistance in the package and degradation and/or failure of the electronics. DARPA's Thermal Management Technologies program has addressed this challenge, supporting the development of mechanically-compliant, low resistivity nano-thermal interface (NTI) materials. In this work, we describe the testing procedure and report the results of NREL's thermal performance and reliability characterization of an initial sample of four different NTI-BIMs.

  1. Deformation Mechanisms in Nanocrystalline Materials

    E-Print Network [OSTI]

    Mohamed, Farghalli A.; Yang, Heather

    2010-01-01

    2010 METALLURGICAL AND MATERIALS TRANSACTIONS A 47. F.A.12. METALLURGICAL AND MATERIALS TRANSACTIONS A VOLUME 41A,of Slip: Progress in Materials Science, Pergamon Press,

  2. Vibrational Damping of Composite Materials

    E-Print Network [OSTI]

    Biggerstaff, Janet M.

    2006-01-01

    Smart Structures and Materials, 3989:531- 538. Biggerstaff,2002. “Electroviscoelastic Materials As Active Dampers”,Smart Structures and Materials, 4695:345-350. Biggerstaff,

  3. Sandia Energy - Wavelength Conversion Materials

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

    Wavelength Conversion Materials Home Energy Research EFRCs Solid-State Lighting Science EFRC Overview Wavelength Conversion Materials Wavelength Conversion MaterialsAlyssa...

  4. ANS materials databook

    SciTech Connect (OSTI)

    Marchbanks, M.F.

    1995-08-01

    Technical development in the Advanced Neutron Source (ANS) project is dynamic, and a continuously updated information source is necessary to provide readily usable materials data to the designer, analyst, and materials engineer. The Advanced Neutron Source Materials Databook (AMBK) is being developed as a part of the Advanced Neutron Source Materials Information System (AMIS). Its purpose is to provide urgently needed data on a quick-turnaround support basis for those design applications whose schedules demand immediate estimates of material properties. In addition to the need for quick materials information, there is a need for consistent application of data throughout the ANS Program, especially where only limited data exist. The AMBK is being developed to fill this need as well. It is the forerunner to the Advanced Neutron Source Materials Handbook (AMHB). The AMHB, as reviewed and approved by the ANS review process, will serve as a common authoritative source of materials data in support of the ANS Project. It will furnish documented evidence of the materials data used in the design and construction of the ANS system and will serve as a quality record during any review process whose objective is to establish the safety level of the ANS complex. The information in the AMBK and AMHB is also provided in electronic form in a dial-up computer database known as the ANS Materials Database (AMDB). A single consensus source of materials information prepared and used by all national program participants has several advantages. Overlapping requirements and data needs of various sub-projects and subcontractors can be met by a single document which is continuously revised. Preliminary and final safety analysis reports, stress analysis reports, equipment specifications, materials service reports, and many other project-related documents can be substantially reduced in size and scope by appropriate reference to a single data source.

  5. Absolute nuclear material assay

    DOE Patents [OSTI]

    Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  6. Absolute nuclear material assay

    DOE Patents [OSTI]

    Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

    2010-07-13

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  7. Nuclear Materials Science

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

    comprises the core actinide materials science and metallurgical capability within the nuclear weapons production and surveillance communities. Contact Us Group Leader David...

  8. Nanoscale Materials in Medicine

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

    Nanoparticle Technology for Drug Delivery. Gao, X., et al. 2002. Journal of Biomedical Optics 7: 532-537. Ferromagnetic materials become superparamagnetic below 20 nm Size...

  9. Webinar: Materials Genome Initative

    Broader source: Energy.gov [DOE]

    Audio recording and text version of the Fuel Cell Technologies Office webinar titled "Materials Genome Initiative," originally presented on December 2, 2014.

  10. Computational Chemical Materials Engineering

    E-Print Network [OSTI]

    . Thermodynamic and micromechanical analysis #12;Home Polyimide-nanotube composites for electro-active materials · (ß ­ CN)APB/ODPA Polyimide · Piezoelectric polyimide · Exceptional thermal, mechanical

  11. Fluorinated elastomeric materials

    DOE Patents [OSTI]

    Lagow, Richard J. (6204 Shadow Mountain, Austin, TX 78731); Dumitru, Earl T. (10116 Aspen St., Austin, TX 78758)

    1986-11-04

    This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

  12. Fluorinated elastomeric materials

    DOE Patents [OSTI]

    Lagow, Richard J. (6204 Shadow Mountain, Austin, TX 78731); Dumitru, Earl T. (10116 Aspen St., Austin, TX 78758)

    1990-02-13

    This invention relates to a method of making perfluorinated elastomeric materials, and to materials made by such methods. In the full synthetic scheme, a partially fluorinated polymeric compound, with moieties to prevent crystallization, is created. It is then crosslinked to a desired degree, then perfluorinated. Various intermediate materials, such as partially fluorinated crosslinked polymers, have useful properties, and are or may become commercially available. One embodiment of this invention therefore relates to perfluorination of a selected partially fluorinated, crosslinked material, which is one step of the full synthetic scheme.

  13. Radiation Safety Training Materials

    Broader source: Energy.gov [DOE]

    The following Handbooks and Standard provide recommended hazard specific training material for radiological workers at DOE facilities and for various activities.

  14. Radioactive Material Transportation Practices

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

    2002-09-23

    Establishes standard transportation practices for Departmental programs to use in planning and executing offsite shipments of radioactive materials including radioactive waste. Does not cancel other directives.

  15. Management of Nuclear Materials

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

    2009-08-17

    To establish requirements for the lifecycle management of DOE owned and/or managed accountable nuclear materials. Cancels DOE O 5660.1B.

  16. Critical Materials Workshop

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

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

  17. Next Generation Materials:

    Office of Environmental Management (EM)

    databases for ICME Surface treatments User facility for remanufactured parts testing; lower-cost coating materials Low-cost laser processing; high accuracy non-planar surface...

  18. Phase Change Material Tower

    Office of Environmental Management (EM)

    transfer of pulverized coal Assortment of available fabrication methods (shrink fit, adhesive, casting) & liner materials (i.e. alumina, SiC, etc.) Pyrotek molten metal transfer...

  19. Composite of refractory material

    DOE Patents [OSTI]

    Holcombe, C.E.; Morrow, M.S.

    1994-07-19

    A composite refractory material composition comprises a boron carbide matrix and minor constituents of yttrium-boron-oxygen-carbon phases uniformly distributed throughout the boron carbide matrix.

  20. Composite of refractory material

    DOE Patents [OSTI]

    Holcombe, Cressie E. (Knoxville, TN); Morrow, Marvin S. (Kingston, TN)

    1994-01-01

    A composite refractory material composition comprises a boron carbide matrix and minor constituents of yttrium-boron-oxygen-carbon phases uniformly distributed throughout the boron carbide matrix.