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1

Hypervelocity impacts and damage laws  

NASA Astrophysics Data System (ADS)

Space debris are nowadays a recognized threat for any space mission. Hypervelocity impacts of space objects can degrade, or terminate prematurely, costly missions. It is, therefore, necessary to improve the survivability of spacecraft. The first step toward this goal is to characterize the behaviour of different materials and configurations under hypervelocity impacts. The purpose of this paper is to present experimental results covering a fairly wide range of materials. Aluminium, carbon fibre reinforced plastics, carbon-carbon, and various type of thermal insulation are considered. The behaviour of sandwich panels with carbon fibre reinforced facings and aluminium honeycomb cores is also investigated. Considerations are given to hypervelocity impacts on gas filled pressure vessels. On the basis of the available data, damage laws are proposed with remarks about their range of applicability.

Lambert, M.

1997-05-01

2

One damage law for different mechanisms  

NASA Astrophysics Data System (ADS)

We consider here a general three-dimensional kinetic damage law. It uses the thermodynamic of irreversible processes formalism and the phenomenological aspects of isotropic damage. It gives the damage rate as a function of its associated variable, the strain energy density release rate and the accumulated plastic strain rate. Associated with different plastic constitutive equations, this damage law takes into account brittle damage, ductile damage, low and high cycle fatigue and creep damage. In this paper we mainly focus on creep-fatigue interaction and high cycle fatigue. Associated to a viscoplastic constitutive equation having kinematic hardening, the damage law gives the non linear creep-fatigue interaction. The agreement with experiments is good. Associated to plastic constitutive equations also having kinematic hardening but introduced in a micromechanical two scale model based on the self-consistent scheme, it models the non linear accumulation of damage induced by a succession of sequences of different amplitudes as well as the effect of the mean stress and the influence of non proportional loading.

Lemaitre, J.; Sermage, J. P.

1997-07-01

3

Laws and Principles of Evolution  

Microsoft Academic Search

First, we note that Evolution is one of Brooks'[1] essential characteristics of software systems: the only systems that are not evolving are the dead ones. Evolution is a basic fact of software life. The fact that we have evolution on multiple levels is often overlooked in considering the fact of evolution: local versus global, component versus system, internally versus externally

Dewayne E. Perry

2002-01-01

4

Stochastic damage evolution in textile laminates  

NASA Technical Reports Server (NTRS)

A probabilistic model utilizing random material characteristics to predict damage evolution in textile laminates is presented. Model is based on a division of each ply into two sublaminas consisting of cells. The probability of cell failure is calculated using stochastic function theory and maximal strain failure criterion. Three modes of failure, i.e. fiber breakage, matrix failure in transverse direction, as well as matrix or interface shear cracking, are taken into account. Computed failure probabilities are utilized in reducing cell stiffness based on the mesovolume concept. A numerical algorithm is developed predicting the damage evolution and deformation history of textile laminates. Effect of scatter of fiber orientation on cell properties is discussed. Weave influence on damage accumulation is illustrated with the help of an example of a Kevlar/epoxy laminate.

Dzenis, Yuris A.; Bogdanovich, Alexander E.; Pastore, Christopher M.

1993-01-01

5

Reexamination of Cumulative Fatigue Damage Laws  

NASA Technical Reports Server (NTRS)

Treatment of accumulated fatigue damage in materials and structures subjected to a history of nonsimple repetitive loadings has received a large amount of attention in recent years. A method used for the treatment of complex loading is known as linear damage rule. It was recognized that, this method could result in unconservative predictions of material and structural behavior. An intense flurry of activity followed in the pursuit of alternative methods of analysis that would predict behavior more accurately. So many methods were introduced that it became necessary periodically to prepare review papers placing all the new methods into perspective. The current integrated view regarding the state of the art as it applies to this effort is discussed. The more recently proposed cumulative damage life prediction methods are reviewed. The double linear damage rule (DLDR), which has evolved over the past 20 years, is reexamined with the intent of improving its accuracy and applicability to engineering problems. Modifications are introduced to the analytical formulation to achieve greater compatibility between the DLDR and the so-called damage curve approach, which is an alternative continuous representation of the DLDR.

Halford, G. R.; Manson, S. S.

1985-01-01

6

Plastic Strain Induced Damage Evolution and Martensitic Transformation in Ductile Materials at Cryogenic Temperatures  

E-print Network

The Fe-Cr-Ni stainless steels are well known for their ductile behaviour at cryogenic temperatures. This implies development and evolution of plastic strain fields in the stainless steel components subjected to thermo-mechanical loads at low temperatures. The evolution of plastic strain fields is usually associated with two phenomena: ductile damage and strain induced martensitic transformation. Ductile damage is described by the kinetic law of damage evolution. Here, the assumption of isotropic distribution of damage (microcracks and microvoids) in the Representative Volume Element (RVE) is made. Formation of the plastic strain induced martensite (irreversible process) leads to the presence of quasi-rigid inclusions of martensite in the austenitic matrix. The amount of martensite platelets in the RVE depends on the intensity of the plastic strain fields and on the temperature. The evolution of the volume fraction of martensite is governed by a kinetic law based on the accumulated plastic strain. Both of thes...

Garion, C

2002-01-01

7

Brittleness Effect on Rock Fatigue Damage Evolution  

NASA Astrophysics Data System (ADS)

The damage evolution mechanism of rocks is one of the most important aspects in studying of rock fatigue behavior. Fatigue damage evolution of three rock types (onyx marble, sandstone and soft limestone) with different brittleness were considered in the present study. Intensive experimental tests were conducted on the chosen rock samples and acoustic emission (AE) sensors were used in some of them to monitor the fracturing process. Experimental tests indicated that brittleness strongly influences damage evolution of rocks in the course of static and dynamic loading. AE monitoring revealed that micro-crack density induced by the applied loads during different stages of the failure processes increases as rock brittleness increases. Also, results of fatigue tests on the three rock types indicated that the rock with the most induced micro-cracks during loading cycles has the least fatigue life. Furthermore, the condition of failure surfaces of the studied rocks samples, subjected to dynamic and static loading, were evaluated and it was concluded that the roughness of failure surfaces is influenced by loading types and rock brittleness. Dynamic failure surfaces were rougher than static ones and low brittle rock demonstrate a smoother failure surface compared to high brittle rock.

Nejati, Hamid Reza; Ghazvinian, Abdolhadi

2014-09-01

8

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2010 CFR

...Determination of damagesapplicable law. (a) The Federal Tort Claims Act. The whole law...general principles of U.S. tort law will apply to property damage...general principles of U.S. tort law will apply. (c) The...

2010-07-01

9

DAMAGE EVOLUTION IN DYNAMIC DEFORMATION OF SILICON CARBIDE  

E-print Network

DAMAGE EVOLUTION IN DYNAMIC DEFORMATION OF SILICON CARBIDE C. J. SHIH{1 , M. A. MEYERS1 {, V. FÐDamage evolution was investigated in silicon carbide by subjecting it to dynamic deformation in (a) a compression®nement (compressive stresses of 19±32 GPa) by a cylindrical (rod) tungsten alloy projectile. Considerable evidence

Meyers, Marc A.

10

Conservation laws and normal forms of evolution equations  

E-print Network

We study local conservation laws for evolution equations in two independent variables. In particular, we present normal forms for the equations admitting one or two low-order conservation laws. Examples include Harry Dym equation, Korteweg-de-Vries-type equations, and Schwarzian KdV equation. It is also shown that for linear evolution equations all their conservation laws are (modulo trivial conserved vectors) at most quadratic in the dependent variable and its derivatives.

Roman O. Popovych; Artur Sergyeyev

2010-03-08

11

On the Evolution of Lehman's Laws Michael W. Godfrey  

E-print Network

On the Evolution of Lehman's Laws Michael W. Godfrey David R. Cheriton School of Computer Science. In his words, "the gross productivity for the project as a whole, and particularly the gross productivity

Godfrey, Michael W.

12

A three-dimensional elastic plastic damage constitutive law for bone tissue.  

PubMed

Motivated by mechanical analysis of bones and bone-implant systems, a 3D constitutive law describing the macroscopic mechanical behaviour of both cortical and trabecular bone in cyclic (not fatigue) overloads is developed. The proposed model which mathematical formulation is established within the framework of generalized standard materials accounts for three distinct material evolution modes where elastic, plastic and damage aspects are closely related. The anisotropic elasticity of bone is described by a morphology-based model and distinct damage behaviour in tension and compression by a halfspacewise generalized Hill criterion. The plastic criterion is based on the intact elastic compliance tensor. The algorithm applies three distinct projections based on the relationship between the internal variables and criteria. Their respective consistent tangent operators are presented. Numerical resolutions of several boundary value problems and a biomechanical application are presented to illustrate the potential of the constitutive model and demonstrate the expected quadratic convergence of the algorithm. PMID:18398628

Garcia, David; Zysset, Philippe K; Charlebois, Mathieu; Curnier, Alain

2009-04-01

13

Local conservation laws of second-order evolution equations  

E-print Network

Generalizing results by Bryant and Griffiths [Duke Math. J., 1995, V.78, 531-676], we completely describe local conservation laws of second-order (1+1)-dimensional evolution equations up to contact equivalence. The possible dimensions of spaces of conservation laws prove to be 0, 1, 2 and infinity. The canonical forms of equations with respect to contact equivalence are found for all nonzero dimensions of spaces of conservation laws.

Roman O. Popovych; Anatoly M. Samoilenko

2008-06-17

14

Plastic strain induced damage evolution and martensitic transformation in ductile materials at cryogenic temperatures  

NASA Astrophysics Data System (ADS)

The Fe-Cr-Ni stainless steels are well known for their ductile behavior at cryogenic temperatures. This implies development and evolution of plastic strain fields in the stainless steel components subjected to thermo-mechanical loads at low temperatures. The evolution of plastic strain fields is usually associated with two phenomena: ductile damage and strain induced martensitic transformation. Ductile damage is described by the kinetic law of damage evolution (cf. [1]). Here, the assumption of isotropic distribution of damage (microcracks and microvoids) in the Representative Volume Element (RVE) is made. Formation of the plastic strain induced martensite (irreversible process) leads to the presence of quasi-rigid inclusions of martensite in the austenitic matrix. The amount of martensite platelets in the RVE depends on the intensity of the plastic strain fields and on the temperature. The evolution of the volume fraction of martensite is governed by a kinetic law based on the accumulated plastic strain (cf. [2]). Both of these irreversible phenomena, associated with the dissipation of plastic power, are included into the constitutive model of stainless steels at cryogenic temperatures. The model is tested on the thin-walled corrugated shells (known as bellows expansion joints) used in the interconnections of the Large Hadron Collider, the new proton storage ring being constructed at present at CERN.

Garion, C.; Skoczen, B. T.

2002-05-01

15

Conservation laws for self-adjoint ?rst order evolution equations  

E-print Network

In this work we consider the problem on group classification and conservation laws of the general first order evolution equations. We obtain the subclasses of these general equations which are quasi-self-adjoint and self-adjoint. By using the recent Ibragimov's Theorem on conservation laws, we establish the conservation laws of the equations admiting self-adjoint equations. We illustrate our results applying them to the inviscid Burgers' equation. In particular an infinite number of new symmetries of these equations are found and their corresponding conservation laws are established.

Igor Leite Freire

2010-02-21

16

Evidence of microstructure evolution in solid elastic media based on a power law analysis  

NASA Astrophysics Data System (ADS)

Complex and consolidated granular media or microcracked composites and metals usually exhibit a high level of nonlinearity in their elastic response already at low amplitudes of excitation. To quantify it, a proper nonlinear indicator y is introduced and its dependence on the excitation amplitude x is studied. The dependence of y on x is found in experiments to be a power law. Here we show that the different power law exponents measured for different materials could be predicted by proper classes of discrete models. An application is presented to link the exponent evolution and the changes of the microstructure due to the progression of damage mechanically induced.

Scalerandi, M.; Idjimarene, S.; Bentahar, M.; El Guerjouma, R.

2015-05-01

17

The evolution of law in biopreparedness.  

PubMed

The decade following the terrorist attacks on September 11, 2001, and ensuing anthrax exposures that same fall has seen significant legal reforms designed to improve biopreparedness nationally. Over the past 10 years, a transformative series of legal changes have effectively (1) rebuilt components of federal, state, and local governments to improve response efforts; (2) created an entire new legal classification known as "public health emergencies"; and (3) overhauled existing legal norms defining the roles and responsibilities of public and private actors in emergency response efforts. The back story as to how law plays an essential role in facilitating biopreparedness, however, is pocked with controversies and conflicts between law- and policymakers, public health officials, emergency managers, civil libertarians, scholars, and others. Significant legal challenges for the next decade remain. Issues related to interjurisdictional coordination; duplicative legal declarations of emergency, disaster, and public health emergency; real-time legal decision making; and liability protections for emergency responders and entities remain unresolved. This article explores the evolving tale underlying the rise and prominence of law as a pivotal tool in national biopreparedness and response efforts in the interests of preventing excess morbidity and mortality during public health emergencies. PMID:22455677

Hodge, James G

2012-03-01

18

Evolution of power law distributions in science and society.  

PubMed

Power law distributions have been observed in numerous physical and social systems; for example, the size distributions of particles, aerosols, corporations, and cities are often power laws. Each system is an ensemble of clusters, comprising units that combine with or dissociate from the cluster. Constructing models and investigating their properties are needed to understand how such clusters evolve. To describe the growth of clusters, we hypothesize that a distribution obeys a governing population dynamics equation based on a reversible association-dissociation process. The rate coefficients are considered to depend on the cluster size as power expressions, thus providing an explanation for the asymptotic evolution of power law distributions. PMID:16241617

Jeon, Young-Pyo; McCoy, Benjamin J

2005-09-01

19

Scale-Dependent Friction and Damage Interface law: implications for effective earthquake rupture dynamics and radiation  

Microsoft Academic Search

Propagation and radiation of an earthquake rupture is commonly considered as a friction dominated process on fault surfaces. Friction laws, such as the slip weakening and the rate-and-state laws are widely used in the modeling of the earthquake rupture process. These laws prescribe the traction evolution versus slip, slip rate and potentially other internal variables. They introduce a finite cohesive

Gaetano Festa; Jean-Pierre Vilotte; Michel Raous; Carole Henninger

2010-01-01

20

The constructal law of design and evolution in nature  

PubMed Central

Constructal theory is the view that (i) the generation of images of design (pattern, rhythm) in nature is a phenomenon of physics and (ii) this phenomenon is covered by a principle (the constructal law): for a finite-size flow system to persist in time (to live) it must evolve such that it provides greater and greater access to the currents that flow through it. This law is about the necessity of design to occur, and about the time direction of the phenomenon: the tape of the design evolution movie runs such that existing configurations are replaced by globally easier flowing configurations. The constructal law has two useful sides: the prediction of natural phenomena and the strategic engineering of novel architectures, based on the constructal law, i.e. not by mimicking nature. We show that the emergence of scaling laws in inanimate (geophysical) flow systems is the same phenomenon as the emergence of allometric laws in animate (biological) flow systems. Examples are lung design, animal locomotion, vegetation, river basins, turbulent flow structure, self-lubrication and natural multi-scale porous media. This article outlines the place of the constructal law as a self-standing law in physics, which covers all the ad hoc (and contradictory) statements of optimality such as minimum entropy generation, maximum entropy generation, minimum flow resistance, maximum flow resistance, minimum time, minimum weight, uniform maximum stresses and characteristic organ sizes. Nature is configured to flow and move as a conglomerate of engine and brake designs. PMID:20368252

Bejan, Adrian; Lorente, Sylvie

2010-01-01

21

The constructal law and the evolution of design in nature  

NASA Astrophysics Data System (ADS)

The constructal law accounts for the universal phenomenon of generation and evolution of design (configuration, shape, structure, pattern, rhythm). This phenomenon is observed across the board, in animate, inanimate and human systems. The constructal law states the time direction of the evolutionary design phenomenon. It defines the concept of design evolution in physics. Along with the first and second law, the constructal law elevates thermodynamics to a science of systems with configuration. In this article we review the more recent work of our group, with emphasis on the advances made with the constructal law in the natural sciences. Highlighted are the oneness of animate and inanimate designs, the origin of finite-size organs on animals and vehicles, the flow of stresses as the generator of design in solid structures (skeletons, vegetation), the universality and rigidity of hierarchy in all flow systems, and the global design of human flows. Noteworthy is the tapestry of distributed energy systems, which balances nodes of production with networks of distribution on the landscape, and serves as key to energy sustainability and empowerment. At the global level, the constructal law accounts for the geography and design of human movement, wealth and communications.

Bejan, Adrian; Lorente, Sylvie

2011-10-01

22

Fatigue Damage Evolution in Silicon Films for Micromechanical Applications  

E-print Network

"! \\' Fatigue Damage Evolution in Silicon Films for Micromechanical Applications by P. Shrotriya, S microelectromechanical systems (MEMS) structures. The surface topography evolu- tion that occurs during cyclic fatigue and Si layers. Finally, the implications of the results are discussed for the prediction of fatigue

Suo, Zhigang

23

Early-state damage detection, characterization, and evolution using high-resolution computed tomography  

NASA Astrophysics Data System (ADS)

Safely using materials in high performance applications requires adequately understanding the mechanisms which control the nucleation and evolution of damage. Most of a material's operational life is spent in a state with noncritical damage, and, for example in metals only a small portion of its life falls within the classical Paris Law regime of crack growth. Developing proper structural health and prognosis models requires understanding the behavior of damage in these early stages within the material's life, and this early-stage damage occurs on length scales at which the material may be considered "granular'' in the sense that the discrete regions which comprise the whole are large enough to require special consideration. Material performance depends upon the characteristics of the granules themselves as well as the interfaces between granules. As a result, properly studying early-stage damage in complex, granular materials requires a means to characterize changes in the granules and interfaces. The granular-scale can range from tenths of microns in ceramics, to single microns in fiber-reinforced composites, to tens of millimeters in concrete. The difficulty of direct-study is often overcome by exhaustive testing of macro-scale damage caused by gross material loads and abuse. Such testing, for example optical or electron microscopy, destructive and further, is costly when used to study the evolution of damage within a material and often limits the study to a few snapshots. New developments in high-resolution computed tomography (HRCT) provide the necessary spatial resolution to directly image the granule length-scale of many materials. Successful application of HRCT with fiber-reinforced composites, however, requires extending the HRCT performance beyond current limits. This dissertation will discuss improvements made in the field of CT reconstruction which enable resolutions to be pushed to the point of being able to image the fiber-scale damage structures and the application of this new capability to the study of early-stage damage.

Grandin, Robert John

24

Emergence of Zipf's Law in the Evolution of Communication  

E-print Network

Zipf's law seems to be ubiquitous in human languages and appears to be a universal property of complex communicating systems. Following the early proposal made by Zipf concerning the presence of a tension between the efforts of speaker and hearer in a communication system, we introduce evolution by means of a variational approach to the problem based on Kullback's Minimum Discrimination of Information Principle. Therefore, using a formalism fully embedded in the framework of information theory, we demonstrate that Zipf's law is the only expected outcome of an evolving, communicative system under a rigorous definition of the communicative tension described by Zipf.

Bernat Corominas-Murtra; Jordi Fortuny; Ricard V. Sol

2011-01-13

25

Dynamic damage nucleation and evolution in multiphase materials  

NASA Astrophysics Data System (ADS)

For ductile metals, dynamic fracture occurs through void nucleation, growth, and coalescence. Previous experimental works in high purity metals have shown that microstructural features such as grain boundaries, inclusions, vacancies, and heterogeneities can act as initial void nucleation sites. However, for materials of engineering significance, those with, second phase particles it is less clear what the role of a soft second phase will be on damage nucleation and evolution. To approach this problem in a systematic manner, two materials have been investigated: high purity copper and copper with 1% lead. These materials have been shock loaded at 1.5 GPa and soft recovered. In-situ free surface velocity information and post mortem metallography reveals the presence of a high number of small voids in CuPb in comparison to a lower number of large voids in Cu. This suggests that damage evolution is nucleation dominated in the CuPb and growth dominated in the pure Cu.

Fensin, S. J.; Escobedo, J. P.; Gray, G. T.; Patterson, B. M.; Trujillo, C. P.; Cerreta, E. K.

2014-05-01

26

Atomistic processes of damage evolution in neutron-irradiated Cu and Ni at high temperature  

Microsoft Academic Search

This paper consists of two parts. In part 1, the experimental results of damage evolution of neutron-irradiated Cu and Ni are described. In part 2, results of computer simulations are described with linkage of experimental data to explore the atomistic process of damage evolution. To study experimentally the atomistic processes of damage evolution in neutron-irradiated Cu and Ni in part

Yoshiharu Shimomura; Ichiro Mukouda; Kenjiro Sugio; Ping Zhao

1999-01-01

27

Fault Wear by Damage Evolution During Steady-State Slip  

NASA Astrophysics Data System (ADS)

Slip along faults generates wear products such as gouge layers and cataclasite zones that range in thickness from sub-millimeter to tens of meters. The properties of these zones apparently control fault strength and slip stability. Here we present a new model of wear in a three-body configuration that utilizes the damage rheology approach and considers the process as a microfracturing or damage front propagating from the gouge zone into the solid rock. The derivations for steady-state conditions lead to a scaling relation for the damage front velocity considered as the wear-rate. The model predicts that the wear-rate is a function of the shear-stress and may vanish when the shear-stress drops below the microfracturing strength of the fault host rock. The simulated results successfully fit the measured friction and wear during shear experiments along faults made of carbonate and tonalite. The model is also valid for relatively large confining pressures, small damage-induced change of the bulk modulus and significant degradation of the shear modulus, which are assumed for seismogenic zones of earthquake faults. The presented formulation indicates that wear dynamics in brittle materials in general and in natural faults in particular can be understood by the concept of a "propagating damage front" and the evolution of a third-body layer.

Lyakhovsky, Vladimir; Sagy, Amir; Boneh, Yuval; Reches, Ze'ev

2014-11-01

28

The Impact of State Laws Limiting Malpractice Damage Awards on Health Care Expenditures  

PubMed Central

Twenty-eight states have laws that limit payments in malpractice cases, and several studies indicate that these laws reduce the frequency and severity of malpractice claims and lower premiums. Moreover, proponents believe that such laws reduce health care expenditures by reducing the practice of defensive medicine. However, there is a dearth of empirical evidence about the impact of these laws on the cost of health care. We used multivariate models and relatively recent data to estimate the impact of state tort reform laws that directly limit malpractice damage payments on health care expenditures. Estimates from these models suggest that laws limiting malpractice payments lower state health care expenditures by between 3% and 4%. PMID:16809580

Hellinger, Fred J.; Encinosa, William E.

2006-01-01

29

Scaling Laws for Convection with Temperature-dependent Viscosity and Grain-damage  

E-print Network

Numerical experiments of convection with grain-damage are used to develop scaling laws for convective heat flow, mantle velocity, and plate velocity across the stagnant lid and plate-tectonic regimes. Three main cases are presented in order of increasing complexity: a simple case wherein viscosity is only dependent on grainsize, a case where viscosity depends on temperature and grainsize, and finally a case where viscosity is temperature and grainsize sensitive, and the grain-growth (or healing) is also temperature sensitive. In all cases, convection with grain-damage scales differently than Newtonian convection due to the effects of grain-damage. For the fully realistic case, numerical results show stagnant lid convection, fully mobilized convection that resembles the temperature-independent viscosity case, and partially mobile or transitional convection, depending on damage to healing ratio, Rayleigh number, and the activation energies for viscosity and healing. Applying our scaling laws for the fully reali...

Foley, Bradford J

2014-01-01

30

Damage evolution in metal matrix composites subjected to thermomechanical fatigue  

SciTech Connect

A thermomechanical analysis of unidirectional continuous fiber metal matrix composites is presented. The analysis includes the effects of processing induced residual thermal stresses, interface cracking, and inelastic matrix behavior on damage evolution. Due to the complexity of the nonlinear effects, the analysis is performed computationally using the finite element method. The interface fracture is modeled by a nonlinear constitutive model. The problem formulation is summarized and results are presented for a four-ply unidirectional SCS-6/{beta}21S titanium composite under high temperature isothermal mechanical fatigue.

Allen, D.H. [Texas A and M Univ., College Station, TX (United States). Center for Mechanics of Composites; Hurtado, L.D.; Helms, K.L.E. [Sandia National Labs., Albuquerque, NM (United States)

1995-05-01

31

Simulation of Damage Evolution in Discontinously Reinforced Metal Matrix Composites  

SciTech Connect

First, a phase-field model for elastic-plastic solids obeying von Mises yield criterion will be described. Then, this phase-field model will be extended to simulate the damage evolution due to nucleation and growth of voids in ductile matrix for discontinuously reinforced composites. The role of reinforcement morphology and the modulus effects leading to final failure all included in the simulations in an effort to make a parametric investigation. The advantages and disadvantages of such phase-field modeling approach in comparison to well established other continuum methods will be elucidated.

Biner, S.B.; Hu, Shenyang Y.

2009-08-01

32

Observation of damage evolution in polymer bonded explosives using acoustic emission and digital image correlation  

Microsoft Academic Search

The Acoustic Emission (AE) and Digital Image Correlation (DIC) methods have been combined to measure and evaluate the damage evolution of Polymer Bonded Explosives (PBXs) under uniaxial compression. The global damage evolution was measured by AE and the local (spatial) distribution of damage observed by DIC. It was found that a Dominant Localization Band (DLB) plays a key role in

Xian Wang; Shaopeng Ma; Yingtao Zhao; Zhongbin Zhou; Pengwan Chen

2011-01-01

33

Defect and damage evolution quantification in dynamically-deformed metals using orientation-imaging microscopy  

SciTech Connect

Orientation-imaging microscopy offers unique capabilities to quantify the defects and damage evolution occurring in metals following dynamic and shock loading. Examples of the quantification of the types of deformation twins activated, volume fraction of twinning, and damage evolution as a function of shock loading in Ta are presented. Electron back-scatter diffraction (EBSD) examination of the damage evolution in sweeping-detonation-wave shock loading to study spallation in Cu is also presented.

Gray, George T., III [Los Alamos National Laboratory; Livescu, Veronica [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory

2010-03-18

34

Bell's Law for the birth and death of computer classes: A theory of the computer's evolution  

Microsoft Academic Search

Bell's Law explains the history of the computing industry based on the properties of computer classes and their determinants. The paper posits a general theory for the creation, evolution, and death of various priced-based computer classes that have come about through circuit and semiconductor technology evolution from 1951. The exponential transistor density increases forecast by Moore's Law (1965,1975) being the

Gordon Bell

2007-01-01

35

On Evidence Supporting the FEAST Hypothesis and the Laws of Software Evolution  

E-print Network

On Evidence Supporting the FEAST Hypothesis and the Laws of Software Evolution M. M. Lehman, D. E process on software product evolution, the FEAST 1 project has examined metric data relating to various support the FEAST hypothesis. Inter alia, the results provide evidence compatible with the laws

Perry, Dewayne E.

36

On-site inspections of pavement damages evolution using GPR  

NASA Astrophysics Data System (ADS)

Ground-penetrating radar (GPR) is being increasingly used for pavements maintenance due to the wide range of applications spanning from physical to geometrical inspections, thereby allowing for a reliable diagnosis of the main causes of road structural damages. In this work, an off-ground GPR system was used to investigate a large-scale rural road network. Two sets of surveys were carried out in different time periods, with the main goals to i) localize the most critical sections; ii) monitor the evolution of previous damages and localize newborn deep faults, although not revealed at the pavement surface level; iii) analyze the causes of both evolution and emergence of faults by considering environmental and human factors. A 1-GHz GPR air-launched antenna was linked to an instrumented van for collecting data at traffic speed. Other support techniques (e.g. GPS data logger, odometer, HD video camera) were used for cross-checking,. Such centre frequency of investigation along with a 25-ns time window allow for a signal penetration of 900 mm, consistent with the deepest layer interfaces. The bottom of the array was 400 mm over the surface, with a minimum distance of 1200 mm from the van body. Scan length of maximum 10 km were provided for avoiding heavy computational loads. The rural road network was located in the District of Rieti, 100 km north from Rome, Italy, and mostly develops in a hilly and mountainous landscape. In most of the investigated roads, the carriageway consists in two lanes of 3.75 meters wide and two shoulders of 0.50 meters wide. A typical road section includes a HMA layer (65 mm average thickness), a base layer (100 mm average thickness), and a subbase layer (300 mm average thickness), as described by pavement design charts. The first set of surveys was carried out in two days at the beginning of spring in moderately dry conditions. Overall, 320-km-long inspections were performed in both travel directions, thereby showing a productivity of approximately 160 km/day at 40 km/h speed, on the average. After processing and first-checking, GPR profiles were divided into homogeneous sections according to the combination of different parameters (e.g. route analyzed, long distance conditions of regularity/irregularity in layers arrangement). In such context, a high consistency between surface damages, mismatches from the GPR scans, and boundary environmental conditions was demonstrated. In addition, deep mismatches were detected even for early-stage or unrevealed faults. The second set of surveys was carried out in autumn in high humidity conditions, due to recent rainfalls. 160 km of relevant routes from the same road network were investigated. Results showed a high consistency with those collected during the first-stage of surveys. Minor changes were found in those sections with low traffic loads (e.g. farther away from the biggest town of Rieti), whereas major mismatches were detected in wetlands (e.g. close to rivers), work zones, and nearby those sections already deeply damaged in the past. This work benefited from networking activities carried out within the EU funded COST Action TU1208 'Civil Engineering Applications of Ground Penetrating Radar'.

Tosti, Fabio; D'Amico, Fabrizio; Calvi, Alessandro; Benedetto, Andrea

2014-05-01

37

Scaling laws for convection with temperature-dependent viscosity and grain-damage  

NASA Astrophysics Data System (ADS)

Numerical experiments of convection with grain-damage are used to develop scaling laws for convective heat flow, mantle velocity and plate velocity across the stagnant lid and plate-tectonic regimes. Three main cases are presented in order of increasing complexity: a simple case wherein viscosity is only dependent on grain size, a case where viscosity depends on temperature and grain size, and finally a case where viscosity is temperature and grain size sensitive, and the grain-growth (or healing) is also temperature sensitive. In all cases, convection with grain-damage scales differently than Newtonian convection; whereas the Nusselt number (Nu), typically scales with the reference Rayleigh number, Ra0, to the 1/3 power, for grain-damage this exponent is larger because increasing Ra0 also enhances damage. In addition, Nu, mantle velocity, and plate velocity are also functions of the damage to healing ratio, (D/H); increasing D/H increases Nu because more damage leads to more vigorous convection. For the fully realistic case, numerical results show stagnant lid convection, fully mobilized convection that resembles the temperature-independent viscosity case, and partially mobile or transitional convection, depending on D/H, Ra0, and the activation energies for viscosity and healing. Applying our scaling laws for the fully realistic case to Earth and Venus we demonstrate that increasing surface temperature dramatically decreases plate speed and heat flow, essentially shutting down plate tectonics, due to increased healing in lithospheric shear zones, as proposed previously. Contrary to many previous studies, the transitional regime between the stagnant lid and fully mobilized regimes is large, and the transition from stagnant lid to mobile convection is gradual and continuous. Thus planets could exhibit a full range of surface mobility, as opposed to the bimodal distribution of fully mobile lid planets and stagnant lid planets that is typically assumed.

Foley, Bradford J.; Bercovici, David

2014-10-01

38

Laws and Principles of Evolution Dewayne E. Perry  

E-print Network

evolution - global evolution, evolution on a large scale. For our work on FEAST [2] we have had what amounts. We need process and organizational data to determine the fate of the FEAST hypothesis [3]. We need

Perry, Dewayne E.

39

Damage Evolution On Mechanical Parts Under Cyclic Loading  

Microsoft Academic Search

This paper presents a fatigue damage model, based on the continuum damage mechanics and general thermodynamic theory, proposed by Lemaitre and Chaboche, for rolling bearings under very numerous loading cycles. A flow surface of fatigue using the Sines criterion is adopted. The coupling between the hardening plasticity and damage effects is considered in the constitutive equations. An explicit algorithm of

P. Lestriez; F. Bogard; J. L. Shan; Y. Q. Guo

2007-01-01

40

On a new law of bone remodeling based on damage elasticity: a thermodynamic approach  

PubMed Central

Background Bone tissue is the main element of the human skeleton and is a dynamic tissue that is continuously renewed by bone-resorbing osteoclasts and bone-forming osteoblasts. The bone is also capable of repairing itself and adapting its structure to changes in its load environment through the process of bone remodeling. Therefore, this phenomenon has been gaining increasing interest in the last years and many laws have been developed in order to simulate this process. Results In this paper, we develop a new law of bone remodeling in the context of damaged elastic by applying the thermodynamic approach in the case of small perturbations. The model is solved numerically by a finite difference method in the one-dimensional bone structure of a n-unit elements model. Conclusion In addition, several numerical simulations are presented that confirm the accuracy and effectiveness of the model. PMID:23194460

2012-01-01

41

Damage Evolution On Mechanical Parts Under Cyclic Loading  

NASA Astrophysics Data System (ADS)

This paper presents a fatigue damage model, based on the continuum damage mechanics and general thermodynamic theory, proposed by Lemaitre and Chaboche, for rolling bearings under very numerous loading cycles. A flow surface of fatigue using the Sines criterion is adopted. The coupling between the hardening plasticity and damage effects is considered in the constitutive equations. An explicit algorithm of weak coupling leads to a calculation very fast. This fatigue damage model is implemented into Abaqus/Explicit using a Vumat user's subroutine. Moreover, the damage variable in function of time is transformed into a function of number of cycles. An algorithm of cycle jump, with a criterion for choosing the number increment of cycles, is proposed, which allows to largely reduce the CPU time. The present damage simulation allows to determine the lifetime of mechanical parts under cyclic loading.

Lestriez, P.; Bogard, F.; Shan, J. L.; Guo, Y. Q.

2007-05-01

42

The Effect of Interfacial Properties on Damage Evolution in Model Composites  

E-print Network

in tension and evaluated using thermoelastic stress analysis (TSA) to observe damage initiation and evolution of the proposed composite systems. Furthermore, design guidelines must be developed to facil- itate the safe

Sottos, Nancy R.

43

A multiscale model for predicting damage evolution in heterogeneous viscoelastic media  

E-print Network

A multiple scale theory is developed for the prediction of damage evolution in heterogeneous viscoelastic media. Asymptotic expansions of the field variables are used to derive a global scale viscoelastic constitutive equation that includes...

Searcy, Chad Randall

2004-11-15

44

Law, evolution and the brain: applications and open questions.  

PubMed Central

This paper discusses several issues at the intersection of law and brain science. It focuses principally on ways in which an improved understanding of how evolutionary processes affect brain function and human behaviour may improve law's ability to regulate behaviour. It explores sample uses of such 'evolutionary analysis in law' and also raises questions about how that analysis might be improved in the future. Among the discussed uses are: (i) clarifying cost-benefit analyses; (ii) providing theoretical foundation and potential predictive power; (iii) assessing comparative effectiveness of legal strategies; and (iv) revealing deep patterns in legal architecture. Throughout, the paper emphasizes the extent to which effective law requires: (i) building effective behavioural models; (ii) integrating life-science perspectives with social-science perspectives; (iii) considering the effects of brain biology on behaviours that law seeks to regulate; and (iv) examining the effects of evolutionary processes on brain design. PMID:15590611

Jones, Owen D

2004-01-01

45

Use of atomic force microscopy for characterizing damage evolution during fatigue  

Microsoft Academic Search

A study of the development of surface fatigue damage in PH 13-8 Mo stainless steel and copper by atomic force microscopy (AFM) was performed. AFM observations allow highly automated, quantitative characterization of surface deformation with a resolution of 5 nm or better, which is ideal for understanding fatigue damage evolution. A secondary objective was to establish a correlation between fatigue

Laurent Cretegny

2000-01-01

46

Collateral damage: Evolution with displacement of fracture distribution and secondary fault strands in fault  

E-print Network

Collateral damage: Evolution with displacement of fracture distribution and secondary fault strands in fault damage zones Heather M. Savage1,2 and Emily E. Brodsky1 Received 22 April 2010; revised 10 faults is governed by the same process. Based on our own field work combined with data from

Savage, Heather M.

47

Evolution Law of Quantum Observables from Classical Hamiltonian in Non-Commutative Phase Space  

E-print Network

The evolution equations of quantum observables are derived from the classical Hamiltonian equations of motion with the only additional assumption that the phase space is non-commutative. The demonstration of the quantum evolution laws is quite general; it does not rely on any assumption on the operator nature of x and p and is independent of the quantum mechanical formalism.

Daniela Dragoman

2006-04-11

48

Emergence of Zipf's Law in the Evolution of Communication Bernat Corominas-Murtra1  

E-print Network

#12;Emergence of Zipf's Law in the Evolution of Communication Bernat Corominas-Murtra1 , Jordi to be ubiquitous in human languages and appears to be a universal property of complex communicating systems of speaker and hearer in a communication system, we introduce evolution by means of a variational approach

49

Ductile damage evolution in high purity copper taylor impact test  

NASA Astrophysics Data System (ADS)

Recently, the continuum damage mechanics model proposed by Bonora (Eng. Fract. Mech. 58, 1997) has been updated to account for stress triaxiality effect on model parameters, (Bonora et al., AIP Conf. Proc. 1195, 2009). This model enhancement allows to predict ductile damage initiation under varying stress states (uniaxial stress, uniaxial strain, and complex load paths) and dynamic loading conditions. In this work, the model has been used to investigate ductile damage developments in Taylor anvil and symmetric Taylor impact (rod-on-rod) configuration. Although the two configurations are equivalent for right scaled impact velocities, experimental evidences show that when ductile damage occurs in rod-on-rod not necessarily also develops in Taylor anvil impact. It has been found that, in the two impact configurations, the stress triaxiality builds up differently with plastic strain leading to different conditions for ductile damage initiation. Taylor impact tests have been designed and performed with the gas-gun facility at the University of Cassino. Damage investigation results obtained on recovered samples have been compared with rod-on-rod data reported in the literature and used to validate the proposed model predictions.

Bonora, Nicola; Ruggiero, Andrew; Iannitti, Gianluca; Testa, Gabriel

2012-03-01

50

Studies on impact constitutive behavior and damage evolution for PP\\/PA polymer blends at large deformation  

Microsoft Academic Search

The dynamic damage evolution and the damage-modified constitutive relation for PP\\/PA polymer blends with different compatibilizers are successfully studied from two approaches: by combining SHPB test with DM-ZWT model and by combining SHPB test with BP neural network. The results consistently show that the damage evolution (including the threshold condition) is dependent on both strain and strain rate.

Z.-J. Sun; L.-L. Wang

2006-01-01

51

Experimental and Analytical Evaluation of Stressing-Rate State Evolution in Rate-State Friction Laws  

NASA Astrophysics Data System (ADS)

Standard rate and state friction laws fail to explain the full range of observations from laboratory friction experiments. A new state evolution law has been proposed by Nagata et al. (2012) that adds a linear stressing-rate-dependent term to the Dieterich (aging) law, which may provide a remedy. They introduce a parameter c that controls the contribution of the stressing rate to state evolution. We show through analytical approximations that the new law can transition between the responses of the traditional Dieterich (aging) and Ruina (slip) laws in velocity step up/down experiments when the value of c is tuned properly. In particular, for c = 0 the response is pure aging while for finite, non-zero c one observes slip law like behavior for small velocity jumps but aging law like response for larger jumps. The magnitude of the velocity jump required to see this transition between aging and slip behaviour increases as c increases. In the limit of c >> 1 the response to velocity steps becomes purely slip law like. In this limit, numerical simulations show that this law loses its appealing time dependent healing property. An approach using Markov Chain Monte Carlo parameter search on data for large magnitude velocity step tests reveals that it is only possible to determine a lower bound on c using datasets that are well explained by the slip law. For a dataset with velocity steps of two orders of magnitude on simulated fault gouge we find this lower bound to be c ? 10.0. This is significantly larger than c ? 2.0 used by Nagata et al. (2012) to fit their data (mainly bare rock experiments with smaller excursions from steady state than our dataset). Similar parameter estimation exercises on slide hold slide data reveal that none of the state evolution laws considered - Dieterich, Ruina, Kato-Tullis and Nagata - match the relevant features of the data. In particular, even the aging law predicts only the correct rate of healing for long hold times but not the correct amount of healing. For c = 10.0, the Nagata law shows significant slip dependence in healing rate for long hold times which is at odds with the lab data and similar to the slip law response. If one accepts frictional healing observed in the laboratory as a ';proper' analog for fault strengthening over the interseismic period, we conclude that none of the investigated state evolution laws provides a comprehensive and correct constitutive relation.

Bhattacharya, P.; Rubin, A. M.; Bayart, E.; Savage, H. M.; Marone, C.; Beeler, N. M.

2013-12-01

52

Metrics and Laws of Software Evolution - The Nineties View  

Microsoft Academic Search

The process of E-type software development and evolution has proven most difficult to improve, possibly due to the fact that the process is a multi-input, multi-output system involving feedback at many levels. This observation, first recorded in the early 70s during an extended study of OS\\/360 evolution, was recently captured in a FEAST hypothesis; a hypothesis being studied in on-going

Meir M. Lehman; Juan F. Ramil; Paul Wernick; Dewayne E. Perry; Wladyslaw M. Turski

1997-01-01

53

Fracture in sheet metal forming: Effect of ductile damage evolution  

Microsoft Academic Search

This work deals with the virtual simulation of the sheet metal stamping process. The main objective is to predict when and where the cracks can appear in the workpiece during the forming operation. A local approach based on the strong coupling between anisotropic elastoplasticity with mixed nonlinear work hardening (isotropic and kinematic) and an isotropic ductile damage is proposed. The

M. Khelifa; M. Oudjene; A. Khennane

2007-01-01

54

Evolution of damage during deformation in porous granular materials (Louis Nel Medal Lecture)  

NASA Astrophysics Data System (ADS)

'Crackling noise' occurs in a wide variety of systems that respond to external forcing in an intermittent way, leading to sudden bursts of energy release similar to those heard when crunching up a piece of paper or listening to a fire. In mineral magnetism ('Barkhausen') crackling noise occurs due to sudden changes in the size and orientation of microscopic ferromagnetic domains when the external magnetic field is changed. In rock physics sudden changes in internal stress associated with microscopically brittle failure events lead to acoustic emissions that can be recorded on the sample boundary, and used to infer the state of internal damage. Crackling noise is inherently stochastic, but the population of events often exhibits remarkably robust scaling properties, in terms of the source area, duration, energy, and in the waiting time between events. Here I describe how these scaling properties emerge and evolve spontaneously in a fully-dynamic discrete element model of sedimentary rocks subject to uniaxial compression at a constant strain rate. The discrete elements have structural disorder similar to that of a real rock, and this is the only source of heterogeneity. Despite the stationary loading and the lack of any time-dependent weakening processes, the results are all characterized by emergent power law distributions over a broad range of scales, in agreement with experimental observation. As deformation evolves, the scaling exponents change systematically in a way that is similar to the evolution of damage in experiments on real sedimentary rocks. The potential for real-time failure forecasting is examined by using synthetic and real data from laboratory tests and prior to volcanic eruptions. The combination of non-linearity and an irreducible stochastic component leads to significant variations in the precision and accuracy of the forecast failure time, leading to a significant proportion of 'false alarms' (forecast too early) and 'missed events' (forecast too late), as well as an over-optimistic assessments of forecasting power and quality when the failure time is known (the 'benefit of hindsight'). The evolution becomes progressively more complex, and the forecasting power diminishes, in going from ideal synthetics to controlled laboratory tests to open natural systems at larger scales in space and time.

Main, Ian

2014-05-01

55

A new conceptual model for damage zone evolution with fault growth  

NASA Astrophysics Data System (ADS)

Faults may either impede or enhance fluid flow in the subsurface, which is relevant to a number of economic issues (hydrocarbon migration and entrapment, formation and distribution of mineral deposits) and environmental problems (movement of contaminants). Fault zones typically comprise a low-permeability core made up of intensely deformed fault rock and a high-permeability damage zone defined by fault-related fractures. The geometry, petrophysical properties and continuity of both the fault core and the damage zone have an important influence on the mechanical properties of the fault systems and on subsurface fluid flow. Information about fault components from remote seismic methods is limited and is available only for large faults (slip larger than 20-100m). It is therefore essential to characterize faults and associated damage zones in field analogues, and to develop conceptual models of how faults and related structures form and evolve. Here we present such an attempt to better understand the evolution of fault damage zones in the Jurassic Aztec Sandstone of the Valley of Fire State Park (SE Nevada). We document the formation and evolution of the damage zone associated with strike-slip faults through detailed field studies of faults of increasing slip magnitudes. The faults initiate as sheared joints with discontinuous pockets of damage zone located at fault tips and fault surface irregularities. With increasing slip (slip >5m), the damage zone becomes longer and wider by progressive fracture infilling, and is organized into two distinct components with different geometrical and statistical characteristics. The first component of the damage zone is the inner damage zone, directly flanking the fault core, with a relatively high fracture frequency and a thickness that scales with the amount of fault slip. Parts of this inner zone are integrated into the fault core by the development of the fault rock, contributing to the core's progressive widening. The second component of the damage zone is the outer damage zone which has a larger and more variable thickness and a lower fracture frequency than the inner zone. The origin and evolution of the inner and outer damage zones are closely related to the history of the fault development as shown in a new conceptual model for damage zone evolution with fault growth. This model forms the basis for a better predictive tool for the attributes of damage zones associated with both large faults that have resolvable slip magnitude and smaller sub-seismic faults in the subsurface.

de Joussineau, G.; Aydin, A.

2006-12-01

56

The power-law expansion universe and dark energy evolution  

E-print Network

In order to depict the transition from deceleration to acceleration expansion of the universe we use a power-law expansion scale factor, $a\\sim t^{n_0+bt^m}$, with $n_0$, $b$ and $m$ three parameters determined by $H_0$, $q_0$ and $z_T$. For the spatially flat, isotropic and homogeneous universe, such a scale factor leads to the results that the dark energy density is slowly changing currently, and predicts the equation of state $w_X$ changes from $w_X>-1$ to $w_X<-1$.

Yi-Huan Wei

2005-02-03

57

Worldtube conservation laws for the null-timelike evolution problem  

E-print Network

I treat the worldtube constraints which arise in the null-timelike initial-boundary value problem for the Bondi-Sachs formulation of Einstein's equations. Boundary data on a worldtube and initial data on an outgoing null hypersurface determine the exterior spacetime by integration along the outgoing null geodsics. The worldtube constraints are a set of conservation laws which impose conditions on the integration constants. I show how these constraints lead to a well-posed initial value problem governing the extrinsic curvature of the worldtube, whose components are related to the integration constants. Possible applications to gravitational waveform extraction and to the well-posedness of the null-timelike initial-boundary value problem are discussed.

Jeffrey Winicour

2011-05-17

58

Stress-weakening effect on friction and a major revision of evolution law for contact state  

NASA Astrophysics Data System (ADS)

Rate and State Friction (RSF) law comprehensively captures important aspects of rock friction and has explained various aspects of fault motion successfully. However, existing RSF laws are clearly incorrect in describing some aspects of friction firmly established by experiments [Beeler et al., 1994]. The shortfall is that the state evolution law which aptly represents time-dependent strengthening of virtually locked faults systematically mispredicts the slip distance required to complete the state evolution caused by changed slip velocity [Marone, 1998; Nakatani, 2001]. To address the problem of evolution law, we observed state variable in RSF continuously in friction experiments on rough granite surfaces. The observation of state variable was performed in the following two independent ways; 1) by subtracting direct effect from measured shear stress 2) by using an acoustic monitoring technique [Nagata et al., 2008]. The latter method is usable even when slip velocity is so low that the former method cannot be used. The former can be regarded as semi-direct measurements of state variable. This method strongly depends on the value of coefficient of direct effect a. Ideally, a is observed as the instantaneous change of applied shear stress (direct effect) upon velocity step. However, the measured shear stress change is much smaller than the real direct effect in reality because the state variable changes considerably before the stress peak. Correction by inferring the change of state using an evolution law is a routine procedure, but the evolution law is in doubt. Hence, before we tackled the evolution law issue, we have designed a special step test where the change of state is minimal and have established that a >0.03. Further, with help of acoustic method, we have identified that a ~0.05. The value is surprisingly large, but agrees very well with the activation volume of silicate lattice. We compared thus observed variation of frictional strength with the prediction of a popular version of evolution law called ageing law [Dieterich, 1979; Ruina, 1983; Beeler, 1994], which explicitly involves both time-dependent healing and slip-dependent weakening. The comparison has shown that an additional shear-stress-dependent weakening term is needed for ageing law to well reproduce the observed variation of frictional strength. Additional independent support for the existence of stress-dependent weakening was obtained from acoustic observation in experiments carefully designed to suppress effects other than shear stress. In further detail, we have observed by acoustic method that the effect diminishes at lower shear stress. Simulations using the modified ageing law reproduced both shear stress and state variable quantitatively well with the same set of parameter values for various types of experiments, which was actually not possible with the original ageing law. Furthermore, the modified law predicts nearly symmetric response to velocity step up and down, as well as it predicts the completion of slip-weakening in a nearly fixed slip distance irrespective of the initial value of state variable; the two major deficits known for the original ageing law has been dissolved.

Nagata, K.; Nakatani, M.; Yoshida, S.

2009-12-01

59

General introduction to microstructural evolution under cascade damage conditions  

SciTech Connect

A short overview of the processes that affect the evolution of the microstructure during irradiation is given. The processes include defect production with an emphasis on the effects of the dynamic cascade events, defect clustering, irradiation-enhanced diffusion, radiation-induced segregation, phase decompositions and phase transformations. A simple model for the description of the development of the defect microstructure in a pure metal during cascade producing irradiation is also outlined which can provide, in principle, defect fluxes required for the description of the microstructural processes such as phase decomposition and irradiation-induced precipitation.

Wiedersich, H.

1993-06-01

60

The Morning after the Year of Darwin. Book review. The Laws of Evolution and the Derived  

E-print Network

Pr:374 The Morning after the Year of Darwin. Book review. The Laws of Evolution a century prior to Charles Darwin's Origin (Darwin 1859). In fact some of the major concepts that laid £69.95. ­ As much of the western scientific community reflects on the Year of Darwin festivities

Badyaev, Alex

61

Characterization of damage evolution in an AM60 magnesium alloy by computed tomography  

Microsoft Academic Search

Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories, California (SNL) are collaborating on the development of new techniques to study damage evolution and growth in material specimens subjected to mechanical loading. These techniques include metallography, radiography, computed tomography (CT) and modeling. The material specimens being studied include cast magnesium and aluminum alloys, and forged stainless steel. We will concentrate

Amy Waters; Harry Martz; Ken Dolan; Mark Horstemeyer; Derrill Rikard; Robert Green

1999-01-01

62

Microstructure: Property correlation. [multiaxial fatigue damage evolution in waspaloy  

NASA Technical Reports Server (NTRS)

Strain controlled torsional and biaxial (tension-torsion) low cycle fatigue behavior of Waspaloy was studied at room temperature as a function of heat treatment. Biaxial tests were conducted under proportional (when the axial and torsional strain cycles are in-phase) and non-proportional (when the axial and torsional strain cycles are 90 deg out-of-phase) cyclic conditions. The deformation behavior under these different cyclic conditions were evaluated by slip trace analysis. For this, a Schmidt-type factor was defined for multiaxial loading conditions and it was shown that when the slip deformation is predominant, non-proportional cycles are more damaging than proportional or pure axial or torsional cycles. This was attributed to the fact that under non-proportional cyclic conditions, deformation was through multiple slip as opposed single slip for other loading conditions, which gave rise to increased hardening. The total life for a given test condition was found to be independent of heat treatment. This was interpreted as being due to the differences in the cycles to initiation and propagation of cracks.

Jayaraman, N.

1990-01-01

63

Damage detection and conductivity evolution in carbon nanofiber epoxy via electrical impedance tomography  

NASA Astrophysics Data System (ADS)

Utilizing electrically conductive nanocomposites for integrated self-sensing and health monitoring is a promising area of structural health monitoring (SHM) research wherein local changes in conductivity coincide with damage. In this research we conduct proof of concept investigations using electrical impedance tomography (EIT) for damage detection by identifying conductivity changes and by imaging conductivity evolution in a carbon nanofiber (CNF) filled epoxy composite. CNF/epoxy is examined because fibrous composites can be manufactured with a CNF/epoxy matrix thereby enabling the entire matrix to become self-sensing. We also study the mechanisms of conductivity evolution in CNF/epoxy through electrical impedance spectroscopy (EIS) testing. The results of these tests indicate that thermal expansion is responsible for conductivity evolution in a CNF/epoxy composite.

Tallman, T. N.; Gungor, S.; Wang, K. W.; Bakis, C. E.

2014-04-01

64

Radiation-induced damage and evolution of defects in Mo  

SciTech Connect

The formation of defects in bcc Mo lattice as a result of 50-keV Xe bombardment is studied via atomistic simulation with an interatomic potential developed using the force-matching ab initio based approach. The defect evolution in the cascade is described. Diffusion and interaction of interstitials and vacancies are analyzed. Only small interstitial atom clusters form directly in the cascade. Larger clusters grow only via aggregation at temperatures up to 2000 K. Stable forms of clusters demonstrate one-dimensional diffusion with a very high diffusion coefficient and escape quickly to the open surface. Point vacancies have much lower diffusivity and do not aggregate. The possibility of a large prismatic vacancy loop formation near the impact surface as a result of fast recrystallization is revealed. The mobility of the vacancy dislocation loop segments is high, however, the motion of the entire loops is strongly hindered by neighbor point defects. This paper explains the existence of the large prismatic vacancy loops and the absence of the interstitial loops in the recent experiments with ion irradiation of Mo foils.

Starikov, Sergey V.; Insepov, Zeke; Rest, Jeffrey; Kuksin, Alexey Yu.; Norman, Genri E.; Stegailov, Vladimir V.; Yanilkin, Alexey V. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia and Moscow Institute of Physics and Technology, Dolgoprudny 141700 (Russian Federation)

2011-09-01

65

Impact of Gas Adsorption Induced Coal Matrix Damage on the Evolution of Coal Permeability  

NASA Astrophysics Data System (ADS)

It has been widely reported that coal permeability can change from reduction to enhancement due to gas adsorption even under the constant effective stress condition, which is apparently inconsistent with the classic theoretical solutions. This study addresses this inconsistency through explicit simulations of the dynamic interactions between coal matrix swelling/shrinking induced damage and fracture aperture alteration, and translations of these interactions to permeability evolution under the constant effective stress condition. We develop a coupled coal-gas interaction model that incorporates the material heterogeneity and damage evolution of coal, which allows us to couple the progressive development of damage zone with gas adsorption processes within the coal matrix. For the case of constant effective stress, coal permeability changes from reduction to enhancement while the damage zone within the coal matrix develops from the fracture wall to further inside the matrix. As the peak Langmuir strain is approached, the decrease of permeability halts and permeability increases with pressure. The transition of permeability reduction to permeability enhancement during gas adsorption, which may be closely related to the damage zone development in coal matrix, is controlled by coal heterogeneity, external boundary condition, and adsorption-induced swelling.

Zhu, W. C.; Wei, C. H.; Liu, J.; Xu, T.; Elsworth, D.

2013-11-01

66

Breaking the Law of Valgus: the surprising and unexplained prevalence of medial patellofemoral cartilage damage  

PubMed Central

Objectives To compare the prevalence of medial and lateral patellofemoral (PF) cartilage damage in three large osteoarthritis (OA) studies and determine the relationship of this damage to varus, neutral, and valgus knee alignment. Methods In the Boston OA of the Knee (BOKS), Framingham OA (FOA), and Multicenter OA (MOST) studies, MRIs were read for cartilage morphology at the medial and lateral patella and trochlea femoris using Whole-Organ MRI Scores (WORMS). WORMS scores ? 2 (any cartilage defect), ? 3 (areas of partial thickness loss), ? 4 (diffuse partial thickness loss), and ? 5 (extensive full thickness loss) were all variously considered as thresholds to identify damage that may indicate OA. Full-limb radiographs were measured for mechanical alignment, and varus (< ?2), neutral (?2 to 2), and valgus (> 2) knees were identified. Results The prevalence of medial PF cartilage damage exceeded that of lateral damage in all three OA studies and according to nearly every threshold. Only among severely involved knees (WORMS ? 4 or ? 5) did the prevalence of lateral PF cartilage damage approximate that of medial damage. The high prevalence of medial PF damage persisted in all strata of knee alignment. Even among knees with valgus malalignment, the prevalence of lateral PF cartilage damage equaled or surpassed that of medial PF damage only when the threshold was specific to severely involved knees. Conclusions Medial PF cartilage damage is at least as prevalent among older adults as lateral PF cartilage damage. PMID:22534825

Gross, K. Douglas; Niu, Jingbo; Stefanik, Joshua J.; Guermazi, Ali; Roemer, Frank W.; Sharma, Leena; Nevitt, Michael C.; Segal, Neil A.; Lewis, Cora E.; Felson, David T.

2013-01-01

67

Cumulative creep-fatigue damage evolution in an austenitic stainless steel  

NASA Technical Reports Server (NTRS)

A model of cumulative creep-fatigue damage has been developed which is based on the use of damage curve equations to describe the evolution of creep-fatigue damage for four basic creep-fatigue cycle types. These cycle types correspond to the four fundamental cycles of the Strain Range Partitioning Life Prediction approach of Manson, Halford, and Hirschberg. A concept referred to as Damage Coupling is introduced to analytically account for the differences in the nature of the damage introduced by each cycle type. For application of this model, the cumulative creep-fatigue damage behavior of type 316 stainless steel at 816 C has been experimentally established for the two-level loading cases involving fatigue and creep-fatigue, in various permutations. The tests were conducted such that the lower life (high strain) cycling was applied first, for a controlled number of cycles, and the higher life (lower strain) cycling was conducted at the second level, to failure. The proposed model correlated the majority of the observed cumulative creep-fatigue data.

Mcgaw, Michael A.

1992-01-01

68

Modeling of delamination damage evolution in laminated composites subjected to low velocity impact  

NASA Technical Reports Server (NTRS)

This study examines the delamination evolution, under quasi-static conditions, of laminated polymeric composites with mechanically nonlinear resin rich interfaces. The constitutive behavior of the interface is represented by two models developed by Needleman and Tvegaard. These models assumed that the interfacial tractions, a function of only the interfacial displacement, will behave similarly to the interatomic forces generated during the interatomic seperation. The interface material's parameters control the load at which the delamination growth initiates and the final delamination size. A wide range of damage accumulation responses have been obtained by varying the model parameters. These results show that Tvergaard's model has been found to be better suited of the two models in predicting damage evolution for the configurations examined.

Lo, David C.; Allen, David H.

1994-01-01

69

Disorder and Power-law Tails of DNA Sequence Self-Alignment Concentrations in Molecular Evolution  

E-print Network

Self-alignment concentrations, $c(x)$, as functions of the length $x$ of the identically matching maximal segments in the genomes of a variety of species, present typically power-law tails extending to the largest scales, $c(x) \\propto x^{\\alpha}$, with similar or different negative $\\alpha$s ($<-2$ as observed so far). The relevant fundamental processes of molecular evolution are segmental duplication and point mutation, and that the stick fragmentation phenomenology has been used to account the neutral evolution [F. Massip and P. Arndt, Phys. Rev. Lett., {\\bf 110} 148101 (2012)]. Disorder is intrinsic and, applying quenching, we systematically show with decaying, steady-state and the general full time-dependent solutions that disorders in the configurations of a simple fragmentation system facilitate the various power-law tails. The full time-dependent solution show the possibility of distinct power law(s) at intermediate scales, which seems to be confirmed by some species, such as rice.

Gao, Kun; Zhu, Jian-Zhou

2014-01-01

70

Damage Evolution and Fault reactivation during Stimulation of a Geothermal Reservoir  

NASA Astrophysics Data System (ADS)

In many geothermal projects the generation of additional fluid pathways, for example by injecting fluid into the geothermal well under high pressure, is necessary to achieve the required rate of fluid flow. Because in a number of geological setting pre-existing faults are the prefered target structures for geothermal wells, the interaction between the faults and fluid pressures generated during the stimulation needs to be considered as well as the influence of the faults of fluid flow. Therefore a good understanding of the interaction and feedback between permeability, porous flow and damage evolution is needed. In this study we are using numerical simulations of the coupled hydro-mechanical processes to investigate the relation between fluid injection, damage evolution and possible fault reactivation in a simplified model of a geothermal reservoir. The simulations are based on a Finite Element model including the damage evolution procedure developed by Karrech et al. 2014 [1]. The geometry, material properties and stress conditions used in the models are based on the available data from the geothermal site in Soultz-sous-Forets (France). The dominant geometrical structure in the model is a steeply dipping fault zone. Otherwise the rock is considered homogeneous. The geometry of the fault zone and its location relative to the well is simplified from Evans et al. 2005 [2]. The stress boundary conditions are taken from Cornet et al. 2007 [3]. Initial results show that the evolution of the damage, and therefore the permeability, in the model is strongly dependent on the material parameters, in particular the amount of pre-existing damage in fault zone. Under the injection pressures considered in this study a reactivation of the fault appears to be feasible only if the fault is already very weak prior to the stimulation. [1] A.Karrech, C.Schrank, R.Freij-Ayoub and K.Regenauer-Lieb, 2014, A multi-scaling approach to predict hydraulic damage of poromaterials, Int. J. Mech. Sci., v. 78, p. 1-7 [2] K.F.Evans, A.Genter and J. Sausse, 2005, Permeability creation and damage due to massive fluid injections into granite at 3.5 km at Soultz: 1. Borehole observations, J. Geophys. Res., v. 110, B04203 [3] F.H. Cornet, Th. Berard and S. Bourouis, 2007, How close to failure is a granite rock mass at a 5km depth?, Int. J. Rock. Mech. Min. Sci., v. 44, p. 47-66

Abe, Steffen; Karrech, Ali; Regenauer-Lieb, Klaus; Deckert, Hagen

2014-05-01

71

26 CFR 1.162-22 - Treble damage payments under the antitrust laws.  

Code of Federal Regulations, 2010 CFR

...under the antitrust laws. 1.162-22 Section...same as in example (1). Example 3...facts as in example (1) except that Z Co...Federal antitrust laws as the criminal action...deducting as a trade or business expense the...

2010-04-01

72

MMonCa: An Object Kinetic Monte Carlo simulator for damage irradiation evolution and defect diffusion  

NASA Astrophysics Data System (ADS)

In this work, we introduce the Object Kinetic Monte Carlo (OKMC) simulator MMonCa and simulate the defect evolution in three different materials. We start by explaining the theory of OKMC and showing some details of how such theory is implemented by creating generic structures and algorithms in the objects that we want to simulate. Then we successfully reproduce simulated results for defect evolution in iron, silicon and tungsten using our simulator and compare with available experimental data and similar simulations. The comparisons validate MMonCa showing that it is powerful and flexible enough to be customized and used to study the damage evolution of defects in a wide range of solid materials.

Martin-Bragado, Ignacio; Rivera, Antonio; Valles, Gonzalo; Gomez-Selles, Jose Luis; Caturla, Mara J.

2013-12-01

73

Dynamic damage evolution in aluminum as a model system for understanding FCC materials in extreme conditions  

NASA Astrophysics Data System (ADS)

Materials play a key role in many emerging technologies. Future technologies in the energy and defense sectors will place huge demands on material performance with respect to stress, strain, temperature, and pressure. These applications require that the response of materials on dynamic (microsecond) time scales be predictable and controllable. Hence, the goal of this research project was to study the extreme environment of shock loaded damage evolution in aluminum as a model system for understanding dynamic response of FCC metals in these environments. Phase one utilized plate impact experiments to study the influence of spatial effects (in the form of microstructural defect distributions) on the dynamic damage evolution process. Samples were soft recovered for shot analysis and comparison to real time laser velocimetry. Results revealed that the length scale of defects controls the failure mechanisms of the microstructure; suggesting defect density and the spatial distribution of defects are critical factors in the deformation process in extreme environments. Phase two studied the influence of kinetic effects (in the form of dynamic tensile loading rate) to reveal time dependence on the dynamic deformation process. Results concluded damage nucleation and growth rates are highly time dependent and can be overdriven as higher tensile loading rates result in extremely short time durations. It was shown that laser velocimetry provides an adequate means for understanding the dynamic damage evolution process when soft recovery of the sample is unavailable. This was shown by comparing laser velocimetry results with data obtained from optical analysis on recovered specimens. The methodology here provides a means to systematically study materials of interest in extreme conditions and provides a pathway for obtaining the relevant physics needed for model development leading to a predictive capability.

Sanchez, Nathaniel Jonathon

74

Frictional response to velocity steps and 1-D fault nucleation under a state evolution law with stressing-rate dependence  

NASA Astrophysics Data System (ADS)

A new state evolution law has recently been proposed by Nagata et al. (2012) that includes a dependence upon stressing rate through a laboratory derived proportionality constant c. It has been claimed that this law, while retaining the time-dependent healing of the Dieterich (or Aging) law, can also match the symmetric response of the Ruina (or Slip) law to velocity step tests. We show through analytical approximations and numerical results that the new law transitions between the responses of the traditional Aging and Slip laws in velocity step-up/step-down experiments when the value of c is tuned properly. Particularly, for c=0, the response is pure Aging, while for finite, nonzero c one observes Slip law type behavior for small velocity jumps but Aging law type response for larger jumps. The magnitude of the velocity jump required to see this transition between aging and slip behaviors increases as c increases. In the limit of c?1 the response becomes purely Slip law type for all geologically plausible velocity jumps. We also present results from detailed analytical and numerical studies of the mechanism of rupture nucleation on 1-D faults under this new state evolution law to demonstrate that the style of nucleation can also be made to switch from Aging-type (expanding cracks) to Slip-type (slip pulses) by adjusting the value of c as indicated by the velocity step results.

Bhattacharya, P.; Rubin, A. M.

2014-03-01

75

Modeling of Progressive Damage in High Strain---Rate Deformations of Fiber-Reinforced Composites  

Microsoft Academic Search

We use the theory of internal variables, or equivalently of continuum damage mechanics, to develop a mathematical model involving three variables to describe the evolution of progressive damage in high strain---rate deformations of fiber-reinforced composites. The degradation of material parameters with the damage is considered. Values of material parameters in the postulated evolution laws of internal variables are determined from

Romesh C. Batra; Noha M. Hassan

2009-01-01

76

Simulation of Damage Evolution in Composites: A Phase-field Model  

SciTech Connect

First, a phase-field model for elastic-plastic solids obeying von Mises yield criterion will be described. Then, this phase-field model will be extended to simulate the damage evolution due to nucleation and growth of voids in ductile matrix for discontinuously reinforced composites. The role of reinforcement morphology and the modulus effects leading to final failure all included in the simulations in an effort to make a parametric investigation. The advantages and disadvantages of such phase-field modeling approach in comparison to well established other continuum methods will be elucidated.

Biner, S.B.; Hu, Shenyang Y.

2009-04-01

77

A Damage Mechanics Treatment of Creep Failure in Rock Salt  

Microsoft Academic Search

Recent progress in the formulation of a constitutive model for describing coupled creep and damage development in rock salt is summarized. The constitutive model is based on the assumption that both dislocation slip and creep damage in the form of microcracks with possible wing-tips contribute to the macroscopic inelastic strain rate. The relevant kinetic equations, flow law, and damage evolution

K. S. Chan; S. R. Bodner; A. F. Fossum; D. E. Munson

1997-01-01

78

Jurisdiction and applicable law in cases of damage from space in EuropeThe advent of the most suitable choiceRome II  

NASA Astrophysics Data System (ADS)

Liability for space activities is a much discussed subject and the advent of commercial space operations has only added to its importance. Articles VI and VII Outer Space Treaty, together with Articles II and III Liability Convention, remain the main entry level for state liability for damage arising from private space activities. Few space-faring nations have introduced national space statutes that include a flow down of their international obligations. The European Union (EU) Regulation on the law applicable to non-contractual obligationshereinafter Rome II Regulationcould harbour developments for liability law in the context of damage resulting from space operations. Space activities were not the main focus of the Regulation but may well turn out to be an interesting spin-off. The Regulation prescribes general rules that will determine the law applicable to damage scenarios where more than one legal system applies. It is important for trans-national tort cases in that it does not limit the rules of applicable law to EU Member States only. This paper focuses on the common rules applicable to damage actions based on torts or other non-contractual obligations as they apply to damage caused by space activities. After an assessment of the relevant international and national law norms, the impact of the Rome II Regulation will be addressed.

Smith, Lesley Jane; Doldirina, Catherine

2010-01-01

79

Damage and Microstructure Evolution in GaN under Au Ion Irradiation  

SciTech Connect

Damage and microstructure evolution in gallium nitride (GaN) under Au+ ion irradiation has been investigated using complementary electron microscopy, secondary ion mass spectrometry and ion beam analysis techniques. Epitaxially-grown GaN layers (2-um-thick) have been irradiated by 2.0 MeV Au ions to 1.0 1015 and 1.4 1015 cm-2 at 155 K and 7.3 1015 cm-2 at 200 K. The irradiation-induced damage has been analyzed by Rutherford backscattering spectroscopy in a channeling direction (RBS/C). For a better determination of ion-induced disorder profile, an iterative procedure and a Monte Carlo code (McChasy) are combined to analyze the ion channeling spectra. With increasing irradiation dose, separated amorphous layers develop from the sample surface and near the damage peak region. Formation of large nitrogen bubbles with sizes up to 70 nm is observed in the buried amorphous layer, while the surface layer contains small bubbles with diameter of a few nanometers due to significant nitrogen loss from the surface. Volume expansion from 3% to 25% in the irradiated region is suggested by cross sectional transmission electron microscope and RBS/C measurement. The anomalous shape of the Au distributions under three irradiations indicates out-diffusion of Au toward sample surface. The results from the complementary techniques suggest that nitrogen is retained in the damaged GaN where the crystallinity is preserved. Once the amorphous state is reached in the surface region, GaN starts to decompose and nitrogen escapes from the surface. Furthermore, experimental results show considerable errors in both disorder profile and ion range predicted by the Stopping and Range of Ions in Matter code, indicating a significant overestimation of electronic stopping powers of Au ions in GaN.

Zhang, Yanwen; Ishimaru, Manabu; Jagielski, Jacek; Zhang, Weiming; Zhu, Zihua; Saraf, Laxmikant V.; Jiang, Weilin; Thome, Lionel; Weber, William J.

2010-02-11

80

Atomistic processes of damage evolution in neutron-irradiated Cu and Ni at high temperature  

NASA Astrophysics Data System (ADS)

This paper consists of two parts. In part 1, the experimental results of damage evolution of neutron-irradiated Cu and Ni are described. In part 2, results of computer simulations are described with linkage of experimental data to explore the atomistic process of damage evolution. To study experimentally the atomistic processes of damage evolution in neutron-irradiated Cu and Ni in part 1, we prepare two types of specimens for both metals. One is as-received specimen from manufacturer. Another is a residual-gas-free specimen which is prepared by melting as-received metals in highly evacuated vacuum at 10-5 Pa. Specimens are irradiated with fission neutrons in the temperature-controlled-irradiation capsule at JMTR (Japan Materials Testing Reactor). TEM (Transmission Electron Microscope) observation shows that the dislocation structure is developed by the aggregation of interstitial clusters in irradiated metals. It is found that the number density of void which are observed in specimens, both as-received and residual-gas-free, that are irradiated to a low fluence such as 5.3 1018 n/cm2 at high temperature of 200C is the same. This suggests that gas atoms are not responsible for the nucleation of voids at high temperature above 200C in neutron-irradiated Cu and Ni. There are two characteristic temperatures of Tsft and Tvoid for the formation of stacking fault tetrahedra (sfts) and voids at high temperature, below Tsft only sft forms and above Tvoid only voids are observed. Tsft is 180C and 250C for Cu and Ni, respectively. Tvoid is 250C and 270C for Cu and Ni, respectively. In situ annealing experiments of neutron-irradiated specimen are carried out to examine the behavior of voids and sfts at high temperature. It is found that voids move as a cluster and that sfts coalesce and disappear spontaneously without shrinkage of their size. In part 2, Computer simulations of molecular dynamics and molecular statics are carried out to study the atomistic process of damage evolution in neutron-irradiated Cu and Ni at high temperatures. Interstitial clusters relax to a bundle of <110> crowdions and move one-dimensionally with a small activation energy such as 0.001eV. The migration of interstitial bundles reacts sensitively to strain fields. Interstitial clusters then form their grouping. The activation energy of an interstitial bundle to change their crowdion direction to another one is about 1 eV. This is an important factor for the evolution of dislocation structure. At high temperatures, a vacancy cluster of sfts and voids relaxes to a movable structure of string shape. Vacancy clusters move and coalesce with other clusters. The activation energy is as small as those that vacancy clusters move as a cluster without an evaporation as a single vacancy. Voids can nucleate at high temperature without trapping of any gas atoms in small vacancy clusters. Voids nucleate uniformly in specimens irradiated to a low fluence. Micro-voids migrate under the influence of strain fields and segregate near dislocation lies. At high temperature, vacancy clusters relax to the movable structure of string shape. This may explain the results of recent varying temperature irradiation at high temperature. At high temperature, vacancies are stored in a supersaturated state in a crystal as small vacancy clusters and clustering of vacancies proceed by cluster migration.

Shimomura, Yoshiharu; Mukouda, Ichiro; Sugio, Kenjiro; Zhao, Ping

81

Characterization of damage evolution in an AM60 magnesium alloy by computed tomography  

NASA Astrophysics Data System (ADS)

Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories, California (SNL) are collaborating on the development of new techniques to study damage evolution and growth in material specimens subjected to mechanical loading. These techniques include metallography, radiography, computed tomography (CT) and modeling. The material specimens being studied include cast magnesium and aluminum alloys, and forged stainless steel. We will concentrate on characterizing monotonically loaded magnesium alloy specimens using computed tomography. Several notched tensile specimens were uniaxially loaded to different percentages of the failure load. Specimens were initially characterized by radiography and computed tomography to determine the preloaded state. Subsequent CT scans were performed after the samples were loaded to different percentages of the load failure. The CT volumetric data are being used to measure void size, distribution and orientation in all three dimensions nondestructively to determine the effect of void growth on the mechanical behavior of the materials.

Waters, Amy; Martz, Harry; Dolan, Ken; Horstemeyer, Mark; Rikard, Derrill; Green, Robert

1999-12-01

82

Characterization of damage evolution in an AM60 magnesium alloy by computed tomography  

SciTech Connect

Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories, California (SNL) are collaborating on the development of new techniques to study damage evolution and growth in material specimens subjected to mechanical loading. These techniques include metallography, radiography, computed tomography (CT) and modeling. The material specimens being studied include cast magnesium and aluminum alloys, and forged stainless steel. We will concentrate on characterizing monotonically loaded magnesium alloy specimens using computed tomography. Several notched tensile specimens were uniaxially loaded to different percentages of the failure load. Specimens were initially characterized by radiography and computed tomography to determine the preloaded state. Subsequent CT scans were performed after the samples were loaded to different percentages of the load failure. The CT volumetric data are being used to measure void size, distribution and orientation in all three dimensions nondestructively to determine the effect of void growth on the mechanical behavior of the materials.

Waters, Amy; Green, Robert [Center for Nondestructive Evaluation, 3400 N. Charles St., Baltimore, Maryland 21218 (United States); Martz, Harry; Dolan, Ken; Rikard, Derrill [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Horstemeyer, Mark [Sandia National Laboratories, 7011 East Ave., Livermore, California 94550 (United States)

1999-12-02

83

Characterization of damage evolution in an AM60 magnesium alloy by computed tomography  

SciTech Connect

Lawrence Livermore National Lab and Sandia National Laboratories, CA are collaborating on the development of new techniques to study damage evolution and growth in material specimens subjected to mechanical loading. These techniques include metallography, radiography, computed tomography (CT) and modeling. The material specimens being studied include cast magnesium and aluminum alloys, and forged stainless steel. The authors concentrate on characterizing monotonically loaded Mg alloy specimens using CT. Several notched tensile specimens were uniaxially loaded to different percentages of the failure load. Specimens were initially characterized by radiography and computed tomography to determine the preloaded state. Subsequent CT scans were performed after the samples were loaded to different percentages of the load failure. The CT volumetric data are being used to measure void size, distribution and orientation in all three dimensions nondestructively to determine the effect of void growth on the mechanical behavior of the materials.

Waters, A.; Green, R.E.; Martz, H.; Dolan, K.; Horstemeyer, M.; Derrill, R.

1999-06-16

84

Modeling the long-term evolution of the primary damage in ferritic alloys using coarse-grained methods  

SciTech Connect

Knowledge of the long-term evolution of the microstructure after introduction of primary damage is an essential ingredient in understanding mechanical property changes that occur during irradiation. Within the European integrated project PERFECT, different techniques have been developed or improved to model microstructure evolution of Fe alloys under irradiation. This review paper aims to present the current state of the art of these techniques, as developed in the project, as well as the main results obtained.

Becquart, C. S. [Universite de Lille; Domain, C. [EDF R& D, Clamart, France; Golubov, Stanislav I [ORNL; Stoller, Roger E [ORNL; Zschack, P. [Argonne National Laboratory (ANL); Barbu, Alain [CEA, Cetre de Sacaly, Gif-sur-Yvette, France; Bocquet, J.L. [CEA, Cetre de Sacaly, Gif-sur-Yvette, France; Caturla, Maria-Jose [Universidad de Alicante; Hou, Marc [Universite Libre de Bruxelles, Brussels, Belgium; Fu, Chu-chun [CEA, Cetre de Sacaly, Gif-sur-Yvette, France; Ortiz, C. J. [Laboratory Nacional de Fusion, CIEMAT; Soudi, A. [Centre Universitaire de Saida, Algeria

2010-01-01

85

PCA algorithm for detection, localisation and evolution of damages in gearbox bearings  

NASA Astrophysics Data System (ADS)

A fundamental aspect when dealing with rolling element bearings, which often represent a key component in rotating machineries, consists in correctly identifying a degraded behaviour of a bearing with a reasonable level of confidence. This is one of the main requirements a health and usage monitoring system (HUMS) should have. This paper introduces a monitoring technique for the diagnosis of bearing faults based on Principal Component Analysis (PCA). This method overcomes the problem of acquiring data under different environmental conditions (hardly biasing the data) and allows accurate damage recognition, also assuring a rather low number of False Alarms (FA). In addition, a novel criterion is proposed in order to isolate the area in which the faulty bearing stands. Another useful feature of this PCA-based method concerns the capability to observe an increasing trend in the evolution of bearing degradation. The described technique is tested on an industrial rig (designed by Avio S.p.A.), consisting of a full size aeroengine gearbox. Healthy and variously damaged bearings, such as with an inner or rolling element fault, are set up and vibration signals are collected and processed in order to properly detect a fault. Finally, data collected from a test rig assembled by the Dynamics & Identification Research Group (DIRG) are used to demonstrate that the proposed method is able to correctly detect and to classify different levels of the same type of fault and also to localise it.

Pirra, M.; Gandino, E.; Torri, A.; Garibaldi, L.; Machorro-Lpez, J. M.

2011-07-01

86

Prediction of damage evolution in continuous fiber metal matrix composites subjected to fatigue loading  

SciTech Connect

A life prediction model is being developed by the authors for application to metal matrix composites (MMC`s). The systems under study are continuous silicon carbide fibers imbedded in titanium matrix. The model utilizes a computationally based framework based on thermodynamics and continuum mechanics, and accounts for matrix inelasticity, damage evolution, and environmental degradation due to oxidation. The computational model utilizes the finite element method, and an evolutionary analysis of a unit cell is accomplished via a time stepping algorithm. The computational scheme accounts for damage growth such as fiber-matrix debonding, surface cracking, and matrix cracking via the inclusion of cohesive zone elements in the unit cell. These elements are located based on experimental evidence also obtained by the authors. The current paper outlines the formulation utilized by the authors to solve this problem, and recent results are discussed. Specifically, results are given for a four-ply unidirectional composite subjected to cyclic fatigue loading at 650{degrees}C both in air and inert gas. The effects of oxidation on the life of the composite are predicted with the model, and the results are compared to limited experimental results.

Allen, D.; Helms, K.; Lagoudas, D. [Texas A& M Univ., College Station, TX (United States)] [and others

1995-08-01

87

Numerical and Analytical Study of Rupture Nucleation on 1D and 2D Faults Under a New State Evolution Law  

NASA Astrophysics Data System (ADS)

Recently, a new empirical law for the evolution of state for use in the standard rate and state sliding friction framework, has been proposed (Nagata et al., GRL, 2012) which incorporates an additional term in the Ageing law to account for the dependence of the state variable on the instantaneous stressing rate, i.e. d?/dt = 1 - V?/Dc - c?/b? d?/dt. This additional parameter, c, controls the amount of state evolution experienced by the sliding surface across a velocity step. Our study attempts to understand the effect of this proposed stressing rate dependence of state on rupture nucleation. We show through analytical approximations and numerical results that the new law can transition between the responses of the traditional Ageing and Slip laws in velocity step up/down experiments when the value of c is tuned properly. Particularly, for c = 0 the response is pure Ageing law like while for finite, non-zero c one observes Slip law like behaviour for small velocity jumps but Ageing law like response for larger jumps. The magnitude of the velocity jump required to see this transition between Ageing and Slip behaviour increases as c increases. These analytical results are further verified by fitting laboratory friction data. Finally, we present results from detailed analytical and numerical studies of the mechanism of rupture nucleation on 1D and 2D faults under this new state evolution law to demonstrate that the style of nucleation can also be made to switch from Ageing-type (expanding crack type) to Slip-type (slip pulse type) by adjusting the value of c as indicated by the spring-slider analysis.

Bhattacharya, P.; Rubin, A. M.

2012-12-01

88

Evolution of elastic wave speed during shear-induced damage and healing within laboratory fault zones  

NASA Astrophysics Data System (ADS)

faults fail and restrengthen repeatedly during the seismic cycle. Faults restrengthen via a set of processes known collectively as fault healing, which is well documented in the laboratory but less well understood in tectonic fault zones. Recent observations of fault zone wave speed following earthquakes suggest opportunities to connect laboratory and field observations of fault healing. However, existing laboratory data lack detail necessary to identify specific processes linking elastic wave speed to fault damage and healing. Here we document changes in elastic properties during laboratory seismic cycles, simulated via periods of nonshear and quasistatic fault slip. Experiments were conducted on brine-saturated halite under conditions favoring pressure solution, analogous to healing processes within and at the base of the seismogenic zone. We find that elastic wave speed (V) and amplitude (A) correlate with porosity. For each percent of porosity lost during compaction, VP increases by ~3%, VS by ~2%, AP by ~10%, and AS by ~7%. Moreover, V and A decrease with granular dilation during fault slip. With increasing shear strain, fabric formation dominates the ultrasonic signals. We find that fault strength depends on fault porosity, making VP and VS potential proxies for fault strength evolution. Our data show that a 1% change in VP or VS results in a friction increase of 0.01 or 0.02, respectively. Within natural fault zones, advances in monitoring elastic wave speed may provide critical information on the evolution of fault strength and seismic hazard throughout the seismic cycle.

Kaproth, Bryan M.; Marone, Chris

2014-06-01

89

Damage Evolution in Composite Materials and Sandwich Structures Under Impulse Loading  

NASA Astrophysics Data System (ADS)

Damage evolution in composite materials is a rather complex phenomenon. There are numerous failure modes in composite materials stemming from the interaction of the various constituent materials and the particular loading conditions. This thesis is concerned with investigating damage evolution in sandwich structures under repeated transient loading conditions associated with impulse loading due to hull slamming of high-speed marine craft. To fully understand the complex stress interactions, a full field technique to reveal stress or strain is required. Several full field techniques exist but are limited to materials with particular optical properties. A full field technique applicable to most materials is known as thermoelastic stress analysis (TSA) and reveals the variation in sum of principal stresses of a cyclically loaded sample by correlating the stresses to a small temperature change occurring at the loading frequency. Digital image correlation (DIC) is another noncontact full field technique that reveals the deformation field by tracking the motion of subsets of a random speckle pattern during the loading cycles. A novel experimental technique to aid in the study of damage progression that combines TSA and DIC simultaneously utilizing a single infrared camera is presented in this thesis. A technique to reliably perform DIC with an infrared (IR) camera is developed utilizing variable emissivity paint. The thermal data can then be corrected for rigid-body motion and deformation such that each pixel represents the same material point in all frames. TSA is then performed on this corrected data, reducing motion blur and increasing accuracy. This combined method with a single infrared camera has several advantages, including a straightforward experimental setup without the need to correct for geometric effects of two spatially separate cameras. Additionally, there is no need for external lighting in TSA as the measured electromagnetic radiation is emitted by the sample's thermal fields. The particular stress resolution of TSA will depend on properties of the material of interest but the noise floor for the temperature variation is universal to the camera utilized. For the camera system in this thesis, the noise floor was found to be fairly frequency independent with a magnitude of 0.01 C, giving the minimum measurable stress for 2024 aluminum alloy of 3.6 MPa and for Nylon of 0.84 MPa. The average displacement range found during a static DIC test with IR images was 0.1 pixels. The maximum displacement variation at 1 Hz was 0.018 pixels. The average variation in strain at 1 Hz was 25 microstrain comparable to traditional DIC measurements in the visible optical regime. The combined TSA-DIC method in IR was validated with several benchmark example problems including plate structures with holes, cracks, and bimaterials. The validated technique was applied to foam-core sandwich composite beams under repeated simulated wave slamming loading. There are numerous failure modes in sandwich composite materials and the full field stress and strain from TSA and DIC, respectively, allow for improved failure analysis and prediction. Understanding damage in sandwich structures under impulse loading is a complex open area of research and the combined TSA-DIC method provides further insight into the failure process.

Silva, Michael Lee

90

Journal of the Geological Society, London, Vol. 162, 2005, pp. 939949. Printed in Great Britain. Evolution of damage zone geometry and intensity in porous sandstone  

E-print Network

. 939 Evolution of damage zone geometry and intensity in porous sandstone: insight gained from strain materials such as sandstone or limestone, fault-related damage zones form arrays of deformation bands, which-related damage zones within the brittly deformed Jurassic Wingate Sandstone exposed in the Laramide

91

Information on the evolution of severe LWR fuel element damage obtained in the CORA program  

NASA Astrophysics Data System (ADS)

In the CORA program a series of out-of-pile experiments on LWR severe accidental situations is being performed, in which test bundles of LWR typical components and arrangements (PWR, BWR) are exposed to temperature transients up to about 2400C under flowing steam. The individual features of the facility, the test conduct, and the evaluation will be presented. In the frame of the international cooperation in severe fuel damage (SFD) programs the CORA tests are contributing confirmatory and complementary informations to the results from the limited number of in-pile tests. The identification of basic phenomena of the fuel element destruction, observed as a function of temperature, is supported by separate-effects test results. Most important mechanisms are the steam oxidation of the Zircaloy cladding, which determines the temperature escalation, the chemical interaction between UO 2 fuel and cladding, which dominates fuel liquefaction, relocation and resulting blockage formation, as well as chemical interactions with Inconel spacer grids and absorber units ((Ag, In, Cd) alloy or B 4C), which are leading to extensive low-temperature melt formation around 1200C. Interrelations between those basic phenomena, resulting for example in cladding deformation ("flowering") and the dramatic hydrogen formation in response to the fast cooling of a hot bundle by cold water ("quenching") are determining the evolution paths of fuel element destruction, which are to be identified. A further important task is the abstraction from mechanistic and microstructural details in order to get a rough classification of damage regimes (temperature and extent), a practicable analytical treatment of the materials behaviour, and a basis for decisions in accident mitigation and management procedures.

Schanz, G.; Hagen, S.; Hofmann, P.; Schumacher, G.; Sepold, L.

1992-06-01

92

Oxidative DNA damage is important to the evolution of antibiotic resistance: evidence of mutation bias and its medicinal implications.  

PubMed

Several (1) studies have revealed that the reactive oxygen species (ROS) induced by antibacterial stimulation accelerates the evolution of antibiotic resistance, which uncovered new links between oxygen rise and evolution and inspired new strategies to prevent antibiotic resistance. Considering many other mechanisms cause DNA mutations aside from ROS damage, evaluating the significance of oxidative DNA damage in the development of antibiotic resistance is of great interest. In this study, we examined the ratio of G:C?>?T:A transversion to G:C?>?A:T transition in drug-resistant Escherichia coli and Mycobacterium tuberculosis and found that it is significantly higher than the background values. This finding strongly suggests that ROS damage plays a critical role in the development of antibacterial resistance. Considering the long-term co-evolution between host organisms and pathogenic bacteria, we speculate that the hosts may have evolved strategies for combating antibiotic resistance by controlling DNA damage in bacteria. Analysis of the global transcriptional profiles of Staphylococcus aureus treated with berberine (derived from Berberis, a traditional antibacterial medicine) revealed that the transcription of DNA repair enzymes was markedly upregulated, whereas the antioxidant enzymes were significantly downregulated. Thus, we propose that consolidating the DNA repair systems of bacteria may be a viable strategy for preventing antibiotic resistance. (1)These authors contributed equally to this work. PMID:22908856

Wang, Zhong-Yi; Xiong, Min; Fu, Liang-Yu; Zhang, Hong-Yu

2013-01-01

93

Cosmological Evolution of Einstein-Aether Models with Power-law-like Potential  

E-print Network

The so-called Einstein-Aether theory is General Relativity coupled (at second derivative order) to a dynamical unit time-like vector field (the aether). It is a Lorentz-violating theory, and gained much attention in the recent years. In the present work, we study the cosmological evolution of Einstein-Aether models with power-law-like potential, by using the method of dynamical system. In the case without matter, there are two attractors which correspond to an inflationary universe in the early epoch, or a de Sitter universe in the late time. In the case with matter but there is no interaction between dark energy and matter, there are only two de Sitter attractors, and no scaling attractor exists. So, it is difficult to alleviate the cosmological coincidence problem. Therefore, we then allow the interaction between dark energy and matter. In this case, several scaling attractors can exist under some complicated conditions, and hence the cosmological coincidence problem could be alleviated.

Hao Wei; Xiao-Peng Yan; Ya-Nan Zhou

2014-04-15

94

An innovative multi-component variate that reveals hierarchy and evolution of structural damage in a solid: application to acrylic bone cement.  

PubMed

A major limitation of solid mechanics is the inability to take into account the influence of hierarchy and evolution of the inherent microscopic structure on evaluating the performance of materials. Irreversible damage and fracture in solids, studied commonly as cracks, flaws, and conventional material properties, are by no means descriptive of the subsequent responses of the microstructures to the applied load. In this work, we addressed this limitation through the use of a novel multi-component variate. The essence of this variate is that it allows the presentation of the random damage in the amplitude spectrum, probability space, and probabilistic entropy. Its uniqueness is that it reveals the evolution and hierarchy of random damage in multi- and trans-scales, and, in addition, it includes the correlations among the various damage features. To better understand the evolution and hierarchy of random damage, we conducted a series of experiments designed to test three variants of a poly (methyl methacrylate) (PMMA) bone cement, distinguished by the methods used to sterilize the cement powder. While analysis of results from conventional tension tests and scanning electron microscopy failed to pinpoint differences among these cement variants, our multi-component variate allowed quantification of the multi- and trans-scale random damage events that occurred in the loading process. We tested the statistical significance of damage states to differentiate the responses at the various loading stages and compared the damage states among the groups. We also interpreted the hierarchical and evolutional damage in terms of the probabilistic entropy (s), the applied stress (?), and the trajectory of damage state. We found that the cement powder sterilization method has a strong influence on the evolution of damage states in the cured cement specimens when subjected to stress in controlled mechanical tests. We have shown that in PMMA bone cements, our damage state variate has the unique ability to quantify and discern the history and evolution of microstructural damage. PMID:22071983

Qi, Gang; Fan, Ming; Lewis, Gladius; Wayne, Steven F

2012-02-01

95

Measuring Compensation from Credit Reporting Damage: A Comparison of Islamic, Saudi, and American Law in Light of Credit Information Reporting Acts  

E-print Network

.2.2. Statutory Damages under Islamic Law . 205 7.3. Actual Damages ... 205 7.3.1. Measurement of Economic Losses .. 205 7.3.1.1. Market Value 206 7.3.1.1.1. Market Value of Personal Property... 7.3.2.1.1. Providing a Substitute .. 214 7.3.2.1.2. Payment of Monetary Value 214 7.3.2.1.3. Diminution in Value . 215 7.3.2.1.4. Restoration ... 216 19 7.3.2.2. Market Value of Services...

Alhaidary, Mansour

2012-05-31

96

Modeling of the Heterogeneous Damage Evolution at the Granular Scale in Polycrystals under Complex Cyclic Loadings  

Microsoft Academic Search

In this study, a new extension of a micromechanical approach proposed recently by the authors is developed to predict the damaged behavior of polycrystals under various multiaxial cyclic loading paths. The model is expressed in the time dependent plasticity for a small strain assumption. With the framework of the continuum damage mechanics (CDM), it is assumed that a scalar damage

A. Abdul-Latif; M. Chadli

2007-01-01

97

Failure of a welded pressure vessel due to creep: damage initiation, evolution and reheat cracking  

Microsoft Academic Search

Continuum damage mechanics (CDM)-based constitutive equations are reviewed and presented for austenitic AISI 316H stainless steels, which undergo creep deformation and damage at 550C. Two multi-axial stress rupture functions\\/criteria have been utilised. Equations and the finite element computer code, DAMAGE XX, were used to carry out CDM studies of the weldment in an axi-symmetric equivalent of the flank section of

F. Vakili-Tahami; Hayhurst

2007-01-01

98

Relationship between damage evolution and Si-H complexes formation in hydrogen implanted Si  

NASA Astrophysics Data System (ADS)

The lattice damage and the chemical bonding in H implanted Si substrates with different doping levels were analyzed with Rutherford backscattering spectroscopy (RBS) in channeling mode and Infrared Spectroscopy (IR), respectively. We observed that the damage of room temperature implanted Si consisted of Si-H complexes and irradiation induced interstitial/vacancy pairs, and that the lattice damage decreased in the presence of pre-implanted boron. This reduction in lattice damage was most pronounced when B was not activated, regardless of Si substrate type.

Lee, J. K.; Hchbauer, T.; Averitt, R. D.; Nastasi, M.

2004-06-01

99

Compaction localization in Saint-Maximin limestone: Spatial evolution of damage and acoustic emission activity  

NASA Astrophysics Data System (ADS)

The analysis of deformation and failure in many sedimentary settings hinges upon a fundamental understanding of inelastic behavior and failure mode of porous carbonate rocks. Previous laboratory studies on low to intermediate porosity limestone showed that even if porosity had several important effects on the overall mechanical behavior, a similar phenomenology of failure was observed in rocks with porosity ranging from 3 to 18%. Dilatancy and shear localization developed under low confining pressure, while strain hardening and shear-enhanced compaction were observed at elevated confining pressure. Samples deformed in the compactive regime failed by homogeneous cataclastic flow. However, recent field observations revealed the development of deformation bands in higher porosity carbonates. To investigate the development of compaction localization in carbonate rocks, we have conducted a systematic study of deformation and failure in Saint-Maximin limestone of 37% porosity. To investigate the development of compaction localization in carbonate rock, we have conducted a systematic study of deformation and failure in Saint-Maximin limestone of 37% porosity. Two series of conventional triaxial experiments were performed in parallel at room temperature, constant strain rate in both dry and wet conditions at confining pressures between 3 and 50 MPa. Wet experiments were carried out with water in drained conditions at 10 MPa of pore pressure. The first series of experiments were performed at IPG Strasbourg on relatively small samples. The failure modes and spatial distribution of damage were studied systematically in these samples. The second series of experiments were performed on larger samples at ENS Paris. Acoustic emission activity was recorded during these tests. The events were located via 12 piezoelectric transducers attached to the samples. The evolution of P-wave velocity in four directions was also recorded during these experiments. Shear enhanced compaction was observed at all pressures conditions. Compactive shear band developed at low effective pressures, while more complex failure modes involving deformation bands of variable orientations were observed at higher effective pressures. A significant weakening effect of water was also observed in Saint Maximin limestone. Our new data showed that the onset of inelastic compaction in Saint Maximin limestone was, like in porous sandstone, marked by a clear increase in acoustic emission activity both in dry and wet conditions. A relatively modest decrease of Vp was observed during the experiments. Strain gage data, acoustic emission and velocity data confirmed that compaction localization occurred in both dry and wet conditions. * Currently at Andra, Chtenay Malabry , France

Rolland, Alexandra; Schubnel, Alexandre; Baud, Patrick

2010-05-01

100

On the Damage Evolution and the Mechanical Degradation of Glass-Fibre Non-Crimp Fabric Reinforced Epoxy Under Tensile Loading: Experimental and Finite Element Modelling  

Microsoft Academic Search

The stiffness and damage evolution in a quasi-static tensile loaded non-crimp fabric reinforced epoxy was measured. To determine the effective stiffness of the damaged material numerically a finite element analysis was performed. The finite element analysis bases solely on the measured 45 and 90- crack densities and on ply properties calculated by the Rule of Mixtures. The measured and calculated

Andreas Gagel; Karl Schulte

2006-01-01

101

Features in chemical kinetics. I. Signatures of self-emerging dimensional reduction from a general format of the evolution law  

NASA Astrophysics Data System (ADS)

Simplification of chemical kinetics description through dimensional reduction is particularly important to achieve an accurate numerical treatment of complex reacting systems, especially when stiff kinetics are considered and a comprehensive picture of the evolving system is required. To this aim several tools have been proposed in the past decades, such as sensitivity analysis, lumping approaches, and exploitation of time scales separation. In addition, there are methods based on the existence of the so-called slow manifolds, which are hyper-surfaces of lower dimension than the one of the whole phase-space and in whose neighborhood the slow evolution occurs after an initial fast transient. On the other hand, all tools contain to some extent a degree of subjectivity which seems to be irremovable. With reference to macroscopic and spatially homogeneous reacting systems under isothermal conditions, in this work we shall adopt a phenomenological approach to let self-emerge the dimensional reduction from the mathematical structure of the evolution law. By transforming the original system of polynomial differential equations, which describes the chemical evolution, into a universal quadratic format, and making a direct inspection of the high-order time-derivatives of the new dynamic variables, we then formulate a conjecture which leads to the concept of an "attractiveness" region in the phase-space where a well-defined state-dependent rate function ? has the simple evolution dot{? }= - ? ^2 along any trajectory up to the stationary state. This constitutes, by itself, a drastic dimensional reduction from a system of N-dimensional equations (being N the number of chemical species) to a one-dimensional and universal evolution law for such a characteristic rate. Step-by-step numerical inspections on model kinetic schemes are presented. In the companion paper [P. Nicolini and D. Frezzato, J. Chem. Phys. 138, 234102 (2013)], 10.1063/1.4809593 this outcome will be naturally related to the appearance (and hence, to the definition) of the slow manifolds.

Nicolini, Paolo; Frezzato, Diego

2013-06-01

102

Modeling of Progressive Damage in High StrainRate Deformations of Fiber-Reinforced Composites  

Microsoft Academic Search

\\u000a We use the theory of internal variables, or equivalently of continuum damage mechanics, to develop a mathematical model involving\\u000a three variables to describe the evolution of progressive damage in high strainrate deformations of fiber-reinforced composites.\\u000a The degradation of material parameters with the damage is considered. Values of material parameters in the postulated evolution\\u000a laws of internal variables are determined from

Romesh C. Batra; Noha M. Hassan

103

Coda Wave Interferometry Method Applied in Structural Monitoring to Assess Damage Evolution in Masonry and Concrete Structures  

NASA Astrophysics Data System (ADS)

In this experimental program the main goal is to monitor the damage evolution in masonry and concrete structures by Acoustic Emission (AE) signal analysis applying a well-know seismic method. For this reason the concept of the coda wave interferometry is applied to AE signal recorded during the tests. Acoustic Emission (AE) are very effective non-destructive techniques applied to identify micro and macro-defects and their temporal evolution in several materials. This technique permits to estimate the velocity of ultrasound waves propagation and the amount of energy released during fracture propagation to obtain information on the criticality of the ongoing process. By means of AE monitoring, an experimental analysis on a set of reinforced masonry walls under variable amplitude loading and strengthening reinforced concrete (RC) beams under monotonic static load has been carried out. In the reinforced masonry wall, cyclic fatigue stress has been applied to accelerate the static creep and to forecast the corresponding creep behaviour of masonry under static long-time loading. During the tests, the evaluation of fracture growth is monitored by coda wave interferometry which represents a novel approach in structural monitoring based on AE relative change velocity of coda signal. In general, the sensitivity of coda waves has been used to estimate velocity changes in fault zones, in volcanoes, in a mining environment, and in ultrasound experiments. This method uses multiple scattered waves, which travelled through the material along numerous paths, to infer tiny temporal changes in the wave velocity. The applied method has the potential to be used as a "damage-gauge" for monitoring velocity changes as a sign of damage evolution into masonry and concrete structures.

Masera, D.; Bocca, P.; Grazzini, A.

2011-07-01

104

Teaching about Controversial Issues: Resolving Conflict between Creationism and Evolution through Law-Related Education.  

ERIC Educational Resources Information Center

Presents a unit on evolution and creation theories in which students explore the legal issues surrounding the teaching of evolution and creation in biology. Students write preliminary essays, study conflict resolution techniques, and conduct a moot trial of the Scopes case of 1925. A course outline is provided. (MDH)

Morishita, Ford

1991-01-01

105

Study on Law of Groundwater Evolution under Natural and Artificial Forcing with Case study of Haihe River Basin  

NASA Astrophysics Data System (ADS)

The evolution of groundwater is one of the key problems of water cycle study. It is a result of joint effect of natural condition and human activities, but until now the driving forces of groundwater system evolution were not fully understood due to the complexity of groundwater system structures and the uncertainty of affecting factors. Geology, precipitation and human activity are the main factors affecting the groundwater system evolution and interact each other, but the influence of such three factors on groundwater system are not clarified clearly on a macroscopic scale. The precipitation changes the volume of water recharge and the groundwater pumping effect the discharge of groundwater. Another important factor influencing balance of groundwater storage is the underlaying that affects the renewablility of groundwater. The underlaying is decided mainly by geological attributes but also influenced by human activited. The macroscopic environment of groundwater evolves under the natural and anthropic factors. This paper study the general law of groundwater evolution among the factors based on the case study in Haihe River Basin, a typical area with dramatic groundwater change under natural precipitation attenuation and gradually increase of water suuply. Haihe River Basin is located in north-China, covers an area of 320,041 km2 with over 40% plain areas. The plain area of Haihe Basin is densely populated with many large and medium-sized cities, including metropolis of Beijing and Tianjin, and concentrated irrigated areas, playing important roles in China's economy and food production. It is the unique basin where groundwater occupies majority of total water supply in China. Long-term groundwater over-exploitation causes a series of ecological and environmental problems that threats the sustainable development. In this paper, the historical process of groundwater balance in Haihe Basin is divided into three phases by decrease of rainfall and increase of water pumping. The different problems caused by groundwater shrinkage are summarized. The volume of recharge from natural precipitation and artificial water cycle, natural evaporation and groundwater exploitation are analyzed based on water balance. Through the historical data analysis the changing trend of coefficients of groundwater balance discovers the evolution of groundwater. The general law is concluded with deeper analysis displays the contribution of natural and artificial factors causing deterioration of groundwater balance. A general law of groundwater evolution is put forward to describe the affection of both natural and anthropogenic factors with a relation curve. Considering the water demand of future socio-economic development in Haihe River Basin, the prospective of future vision of groundwater cycle is analyzed by the law of groundwater evolution. Iterated scenario analysis based on comparison of ameliorative function on groundwater balance to point out reasonable control on groundwater exploitation and rational water allocation under the condition of completion of South-to-North Water Transfer Project that could bring more than 7 billion m3 into Haihe River Basin from Yantze River. Finally, the advantages and disadvantages are concluded through the case study and the farther research in this field is pointed out.

You, Jinjun; Gan, Hong; Wang, Lin; Bi, Xue; Du, Sisi

2010-05-01

106

Comparing Monofractal and Multifractal Analysis of Corrosion Damage Evolution in Reinforcing Bars  

PubMed Central

Based on fractal theory and damage mechanics, the aim of this paper is to describe the monofractal and multifractal characteristics of corrosion morphology and develop a new approach to characterize the nonuniform corrosion degree of reinforcing bars. The relationship between fractal parameters and tensile strength of reinforcing bars are discussed. The results showed that corrosion mass loss ratio of a bar cannot accurately reflect the damage degree of the bar. The corrosion morphology of reinforcing bars exhibits both monofractal and multifractal features. The fractal dimension and the tensile strength of corroded steel bars exhibit a power function relationship, while the width of multifractal spectrum and tensile strength of corroded steel bars exhibit a linear relationship. By comparison, using width of multifractal spectrum as multifractal damage variable not only reflects the distribution of corrosion damage in reinforcing bars, but also reveals the influence of nonuniform corrosion on the mechanical properties of reinforcing bars. The present research provides a new approach for the establishment of corrosion damage constitutive models of reinforcing bars. PMID:22238682

Xu, Yidong; Qian, Chunxiang; Pan, Lei; Wang, Bingbing; Lou, Chi

2012-01-01

107

Evolution of damage and plasticity in titanium-based, fiber-reinforced composites  

SciTech Connect

The inelastic deformation mechanisms were evaluated for a model titanium-based, fiber-reinforced composite: a beta titanium alloy (Ti-15V-3Al-3Cr-3Sn) reinforced with SiC (SCS-6) fibers. The primary emphasis of this article is to illustrate the sequence in which damage and plasticity evolved for this system. The mechanical responses and the results of detailed microstructural evaluations for the [0][sub 8], [90][sub 8], and [[plus minus]45][sub 2s] laminates are provided. It is shown that the characteristics of the reaction zone around the fiber play a very important role in the way damage and plasticity evolve, particularly in the microyield regime of deformation, and must be included in any realistic constitutive model. Fiber-matrix debonding was a major damage mode for the off-axis systems. The tension test results are also compared with the predictions of a few constitutive models.

Majumdar, B.S. (Universal Energy Systems, Inc., Dayton, OH (United States)); Newaz, G.M. (Battelle Memorial Inst., Columbus, OH (United States)); Ellis, J.R. (NASA Lewis Research Center, Cleveland, OH (United States). Fatigue and Failure Branch)

1993-07-01

108

A Model for Collective Strategy Diffusion in Agent Social Law Evolution  

Microsoft Academic Search

Social law is perceived as evolving through the competition of individual social strategies held by the agents. A strategy with strong authority, accepted by many agents, will tend to diffuse to the remaining agents. The authority of a social strategy is determined by not only the number of but also the collective social positions of its overlaid agents. This paper

Yichuan Jiang; Toru Ishida

2007-01-01

109

Damage evolution during freezethaw cycling of cement mortar, studied by electrical resistivity measurement  

E-print Network

at Buffalo, Buffalo, NY 14260-4400, USA Received 29 August 2001; accepted 6 May 2002 Abstract Damage of the water in the concrete upon cooling, and the thawing upon subsequent heating. The phase transition-8846(02)00856-6 * Corresponding author. Tel.: +1-716-645-2593; fax: +1-716-645- 3875. E-mail address: ddlchung@acsu.buffalo.edu (D

Chung, Deborah D.L.

110

Deformation, structural changes and damage evolution in nanotwinned copper under repeated frictional contact sliding  

E-print Network

. An increase in twin density is found to result in smaller pile-up height and friction coefficient. Compared to surface damage and structural changes, after the initial scratch. However with an increase in the number of sliding passes, the friction coefficient and rate of increase of pile up for all specimens acquire

Suresh, Subra

111

Damage and fatigue Continuum damage mechanics modeling  

E-print Network

Damage and fatigue Continuum damage mechanics modeling for fatigue of materials and structures Cachan Cedex, France desmorat@lmt.ens-cachan.fr ABSTRACT. Application of damage mechanics to fatigue is addressed in the present paper. The ability of Lemaitre's damage law to describe low and high cycle fatigue

112

The Source of Alabamas Abundance of Arbitration Cases: Alabamas Bizarre Law of Damages for Mental Anguish  

E-print Network

This Article gives an overview of arbitration litigation in Alabama, including the evolution of mental anguish jurisprudence in contract cases, especially with regard to the automobile and home industries; a proposal to ...

Simpson, W. Scott; Ware, Stephen J.; Willard, Vickie M.

2004-01-01

113

Collateral damage: rapid exposure-induced evolution of pesticide resistance leads to increased susceptibility to parasites.  

PubMed

Although natural populations may evolve resistance to anthropogenic stressors such as pollutants, this evolved resistance may carry costs. Using an experimental evolution approach, we exposed different Daphnia magna populations in outdoor containers to the carbamate pesticide carbaryl and control conditions, and assessed the resulting populations for both their resistance to carbaryl as well as their susceptibility to infection by the widespread bacterial microparasite Pasteuria ramosa. Our results show that carbaryl selection led to rapid evolution of carbaryl resistance with seemingly no cost when assessed in a benign environment. However, carbaryl-resistant populations were more susceptible to parasite infection than control populations. Exposure to both stressors reveals a synergistic effect on sterilization rate by P. ramosa, but this synergism did not evolve under pesticide selection. Assessing costs of rapid adaptive evolution to anthropogenic stress in a semi-natural context may be crucial to avoid too optimistic predictions for the fitness of the evolving populations. PMID:21884064

Jansen, Mieke; Stoks, Robby; Coors, Anja; van Doorslaer, Wendy; de Meester, Luc

2011-09-01

114

Geophys. J. Int. (2000) 142, 151161 A damage mechanics model for power-law creep and earthquake  

E-print Network

of relatively constant strain rate, with a power-law rheology, as observed in laboratory creep test data of accelerating creep results in theto carry out a static load, or `creep', test; that is, holding a eventual RAS #12;152 I. G. Main by stress intensity reduction at the crack tip as the crack grows. Costin (1987

115

Space Law  

NASA Astrophysics Data System (ADS)

This chapter examines the salient characteristics of Space Law. It analyzes the origins and evolution of Space Law, its main international principles, and some current topics of interest to the scientific community: the delimitation of airspace and outer space, intellectual property, and criminal responsibility.

Hermida, Julian

2006-01-01

116

The Evolution of the Law's Treatment of the Confessions of Mentally Disabled Criminal Suspects  

Microsoft Academic Search

Over the past century, the U.S. Supreme Courts treatment of dubious confessions has evolved in such a way that the protections afforded mentally disabled criminal suspects under the present state of the law are minimal. From an initial focus on the voluntariness of the confession, the standard has shifted to a cursory check for Mirandas rote warnings and the presence

John E Knight

2002-01-01

117

PREDICTION OF PROXIMAL FEMORAL FRACTURE BY USING MECHANICAL QUASI-BRITTLE DAMAGE COUPLED WITH ANISOTROPIC BEHAVIOUR LAW  

E-print Network

and propagation. Until now, direct comparisons of predicted and measured force-displacement curves and complete based on isotropic damage to simulate the force-displacement curve and to profile the fractured areaC are the components of elasticity tensor. To distinguish between tension and compression, a way to consider

Boyer, Edmond

118

On Evidence Supporting the FEAST Hypothesis and the Laws of Software Evolution  

Microsoft Academic Search

As part of its study of the impact of feedbackin the global software process on software productevolution, the FEAST\\/1 project has examined metricdata relating to various systems in different applicationareas. High level similarities in the growth trends of thesystems studied support the FEAST hypothesis. Interalia, the results provide evidence compatible with thelaws of software evolution, subject only to minor adjustmentsof

Meir M. Lehman; Juan F. Ramil; Dewayne E. Perry

1998-01-01

119

The evolution of damage and fracture in iron compacts with various initial porosities  

Microsoft Academic Search

This study evaluated the tensile and compressive mechanical properties of iron compacts of various initial porosities, and determined the effect of deformation on the evolution of porosity, pore size and pore shape. The loss in flow strength with porosity was considerably greater than predicted by Gurson's constitutive model for ductile porous materials, but it was in substantial agreement with recent

W. A. Spitzig; R. E. Smelser; O. Richmond

1988-01-01

120

The effects of shockwave profile shape and shock obliquity on spallation in Cu and Ta: kinetic and stress-state effects on damage evolution(u)  

SciTech Connect

Widespread research over the past five decades has provided a wealth of experimental data and insight concerning shock hardening and the spallation response of materials subjected to square-topped shock-wave loading profiles. Less quantitative data have been gathered on the effect of direct, in-contact, high explosive (HE)-driven Taylor wave (or triangular-wave) loading profile shock loading on the shock hardening, damage evolution, or spallation response of materials. Explosive loading induces an impulse dubbed a 'Taylor Wave'. This is a significantly different loading history than that achieved by a square-topped impulse in terms of both the pulse duration at a fixed peak pressure, and a different unloading strain rate from the peak Hugoniot state achieved. The goal of this research is to quantify the influence of shockwave obliquity on the spallation response of copper and tantalum by subjecting plates of each material to HE-driven sweeping detonation-wave loading and quantify both the wave propagation and the post-mortem damage evolution. This talk will summarize our current understanding of damage evolution during sweeping detonation-wave spallation loading in Cu and Ta and show comparisons to modeling simulations. The spallation responses of Cu and Ta are both shown to be critically dependent on the shockwave profile and the stress-state of the shock. Based on variations in the specifics of the shock drive (pulse shape, peak stress, shock obliquity) and sample geometry in Cu and Ta, 'spall strength' varies by over a factor of two and the details of the mechanisms of the damage evolution is seen to vary. Simplistic models of spallation, such as P{sub min} based on 1-D square-top shock data lack the physics to capture the influence of kinetics on damage evolution such as that operative during sweeping detonation loading. Such considerations are important for the development of predictive models of damage evolution and spallation in metals and alloys.

Gray, George T [Los Alamos National Laboratory

2010-12-14

121

Modeling electrical power absorption and thermally-induced biological tissue damage.  

PubMed

This work develops a model for thermally induced damage from high current flow through biological tissue. Using the first law of thermodynamics, the balance of energy produced by the current and the energy absorbed by the tissue are investigated. The tissue damage is correlated with an evolution law that is activated upon exceeding a temperature threshold. As an example, the Fung material model is used. For certain parameter choices, the Fung material law has the ability to absorb relatively significant amounts of energy, due to its inherent exponential response character, thus, to some extent, mitigating possible tissue damage. Numerical examples are provided to illustrate the model's behavior. PMID:23589115

Zohdi, T I

2014-01-01

122

Topographic signatures and a general transport law for deep-seated landslides in a landscape evolution model  

NASA Astrophysics Data System (ADS)

A fundamental goal of studying earth surface processes is to disentangle the complex web of interactions among baselevel, tectonics, climate, and rock properties that generate characteristic landforms. Mechanistic geomorphic transport laws can quantitatively address this goal, but no widely accepted law for landslides exists. Here we propose a transport law for deep-seated landslides in weathered bedrock and demonstrate its utility using a two-dimensional numerical landscape evolution model informed by study areas in the Waipaoa catchment, New Zealand, and the Eel River catchment, California. We define a non-dimensional landslide number, which is the ratio of the horizontal landslide flux to the vertical tectonic flux, that characterizes three distinct landscape types. One is dominated by stochastic landsliding, whereby discrete landslide events episodically erode material at rates exceeding the long-term uplift rate. Another is characterized by steady landsliding, in which the landslide flux at any location remains constant through time and is greatest at the steepest locations in the catchment. The third is not significantly affected by landsliding. In both the "stochastic landsliding" and "steady landsliding" regimes, increases in the non-dimensional landslide number systematically reduce catchment relief and widen valley spacing, producing long, low angle hillslopes despite high uplift rates. The stochastic landsliding regime captures the frequent observation that deep-seated landslides produce large sediment fluxes from small areal extents while being active only a fraction of the time. We suggest that this model is adaptable to a wide range of geologic settings and is useful for interpreting climate-driven changes in landslide behavior.

Booth, Adam M.; Roering, Josh J.; Rempel, Alan W.

2013-06-01

123

Slip, Crystal Orientation, and Damage Evolution During Thermal Cycling in High-Strain Wafer-Level Chip-Scale Packages  

NASA Astrophysics Data System (ADS)

Wafer-level chip-scale package samples with pre-cross-sectioned edge rows were thermally cycled to study microstructure evolution and damage development. Electron backscattered diffraction (EBSD) and high-energy x-ray diffraction were used to obtain Sn grain orientations and the average coefficient of thermal expansion normal to the board in every joint of the package for samples in the as-fabricated and thermally cycled conditions. The results indicated a near-random distribution of joint orientation. Optical, scanning electron microscopy, and EBSD methods were used to characterize microstructure changes in pre-cross-sectioned samples due to thermal cycling. Slip trace analysis and Orientation Imaging Microscopy (OIM) show that slip systems with high Schmid factors (estimated global shear stress based on the package neutral point) are responsible for the observed microstructure evolution during thermal cycling, which provides information about slip systems that are more easily activated. Two joints were analyzed in detail to evaluate slip activity at different stages of their thermal history. The first case showed that a solidification twin grain boundary misorientation deviated from the twin relationship due to slip activity during thermal cycling, which can influence damage development and the path of crack propagation. The second case showed a new grain orientation developing due to gradual lattice rotation about the Sn [110] axis by a continuous recrystallization mechanism. This rotation was correlated with the operation of slip system { 110 )< {001}. Small tin whiskers emerged from the initially polished chip interface and grew with increasing thermal cycles until a crack developed in the solder that relieved the stress. As the local stresses are not known experimentally, this analysis provides observations that can be compared with a crystal plasticity model simulation.

Zhou, Bite; Zhou, Quan; Bieler, Thomas R.; Lee, Tae-kyu

2015-01-01

124

32 CFR 842.111 - Applicable law.  

Code of Federal Regulations, 2010 CFR

...countries. The general principles of tort law common to the majority of American...of damages. (1) Normally, the law of the place where the act or omission...with general principles of American tort law. (2) Damages in suits...

2010-07-01

125

From Migmatites to Plutons: Power Law Relationships in the Evolution of Magmatic Bodies  

NASA Astrophysics Data System (ADS)

Magma is generated by partial melting from micrometre-scale droplets at the source and may accumulate to form >100 km-scale plutons. Magma accumulation thus spans well over ten orders of magnitude in scale. Here we provide measurements of migmatitic leucosomes and granitic veins in drill cores from the Estonian Proterozoic basement and outcrops at Masku in SW Finland and Montemor-o-Novo, central Portugal. Despite the differences in size and number of measured leucosomes and magmatic veins, differences in host rock types and metamorphic grades, the cumulative width distribution of the studied magmatic leucosomes/veins follows a power law with exponents usually between 0.7 and 1.8. Published maps of the SE Australian Lachlan Fold Belt were used to investigate the distribution of granitoid pluton sizes. The granites occupy ca. 22 % of the 2.6 105 km2 area. The cumulative pluton area distributions show good power law distributions with exponents between 0.6 and 0.8 depending on pluton area group. Using the self-affine nature of pluton shapes, it is possible to estimate the total volume of magma that was expelled from the source in the 2.6 105 km2 map area, giving an estimated 0.8 km3 of magma per km2. It has been suggested in the literature that magma batches in the source merge to form ever-bigger batches in a self-organized way. This leads to a power law for the cumulative distribution of magma volumes, with an exponent m V between 1 for inefficient melt extraction, and 2/3 for maximum accumulation efficiency as most of the volume resides in the largest batches that can escape from the source. If m V ? 1, the mass of the magma is dominated by small batches; in case m = 2/3, about 50 % of all magma in the system is placed in a single largest batch. Our observations support the model that the crust develops a self-organized critical state during magma generation. In this state, magma batches accumulate in a non-continuous, step-wise manner to form ever-larger accumulations. There is no characteristic length or time scale in the partial melting process or its products. Smallest melt segregations and >km-scale plotuns form the end members of a continuous chain of mergers of magma batches.

Soesoo, Alvar; Bons, Paul D.

2014-12-01

126

Conservation Laws and the Multiplicity Evolution of Spectra at the Relativistic Heavy Ion Collider  

E-print Network

Transverse momentum distributions in ultra-relativistic heavy ion collisions carry considerable information about the dynamics of the hot system produced. Direct comparison with the same spectra from $p+p$ collisions has proven invaluable to identify novel features associated with the larger system, in particular, the "jet quenching" at high momentum and apparently much stronger collective flow dominating the spectral shape at low momentum. We point out possible hazards of ignoring conservation laws in the comparison of high- and low-multiplicity final states. We argue that the effects of energy and momentum conservation actually dominate many of the observed systematics, and that $p+p$ collisions may be much more similar to heavy ion collisions than generally thought.

Zbigniew Chaj?cki; Mike Lisa

2008-07-22

127

Models for predicting damage evolution in metal matrix composites subjected to cyclic loading  

SciTech Connect

A thermomechanical analysis of a continuous fiber metal matrix composite (MMC) subjected to cyclic loading is performed herein. The analysis includes the effects of processing induced residual thermal stresses, matrix inelasticity, and interface cracking. Due to these complexities, the analysis is performed computationally using the finite element method. Matrix inelasticity is modelled with a rate dependent viscoplasticity model. Interface fracture is modelled by the use of a nonlinear interface constitutive model. The problem formulation is summarized, and results are given for a four-ply unidirectional SCS-6/{beta}21S titanium composite under high temperature isothermal mechanical fatigue. Results indicate rate dependent viscoplasticity can be a significant mechanism for dissipating the energy available for damage propagation, thus contributing to improved ductility of the composite. Results also indicate that the model may be useful for inclusion in life prediction methodologies for MMC`s.

Allen, D.H.; Hurtado, L.D.; Helms, K.L.E. [Texas A and M Univ., College Station, TX (United States). Center for Mechanics of Composites

1995-03-01

128

Spatially resolved stochastic cluster dynamics for radiation damage evolution in nanostructured metals  

NASA Astrophysics Data System (ADS)

A spatially resolved stochastic cluster dynamics (SRSCD) model is introduced to describe radiation-induced defect evolution in metals. The stochastic nature of the method allows SRSCD to model more chemical species and more mobile defects than rate theory methods without loss of computational efficiency, while reaching larger timescales and simulating larger volumes than object-oriented kinetic Monte Carlo (OKMC) methods. To comprehend the capabilities of the method and access new understanding of defect evolution, SRSCD is used in three scenarios. In the first, the results of Frenkel pair implantation are found to match those of rate theory in both spatially homogeneous and spatially resolved media. Next, to study spatial resolution effects and correspondence to OKMC, the results of 20 keV cascade implantation into copper is simulated and an acceptable match with OKMC is found. Finally the method is used to study the problem of helium desorption in thin iron foils. The model is compared with available experimental measures and is found to be in good agreement. The ability of SRSCD to include many mobile species of defects allows a detailed analysis of the mechanisms of helium release from the free surface of the iron foils. As a result new dominant mechanisms of helium release are discussed as well as their operating regimes.

Dunn, Aaron Y.; Capolungo, Laurent; Martinez, Enrique; Cherkaoui, Mohammed

2013-11-01

129

Damage-induced nonassociated inelastic flow in rock salt  

SciTech Connect

The multi-mechanism deformation coupled fracture model recently developed by CHAN, et al. (1992), for describing time-dependent, pressure-sensitive inelastic flow and damage evolution in crystalline solids was evaluated against triaxial creep experiments on rock salt. Guided by experimental observations, the kinetic equation and the flow law for damage-induced inelastic flow in the model were modified to account for the development of damage and inelastic dilatation in the transient creep regime. The revised model was then utilized to obtain the creep response and damage evolution in rock salt as a function of confining pressure and stress difference. Comparison between model calculation and experiment revealed that damage-induced inelastic flow is nonassociated, dilatational, and contributes significantly to the macroscopic strain rate observed in rock salt deformed at low confining pressures. The inelastic strain rate and volumetric strain due to damage decrease with increasing confining pressures, and all are suppressed at sufficiently high confining pressures.

Chan, K.S.; Bodner, S.R. [Southwest Research Inst., San Antonio, TX (United States); Brodsky, N.S.; Fossum, A.F. [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1993-06-01

130

Deformation failure characteristics of coal body and mining induced stress evolution law.  

PubMed

The results of the interaction between coal failure and mining pressure field evolution during mining are presented. Not only the mechanical model of stope and its relative structure division, but also the failure and behavior characteristic of coal body under different mining stages are built and demonstrated. Namely, the breaking arch and stress arch which influence the mining area are quantified calculated. A systematic method of stress field distribution is worked out. All this indicates that the pore distribution of coal body with different compressed volume has fractal character; it appears to be the linear relationship between propagation range of internal stress field and compressed volume of coal body and nonlinear relationship between the range of outburst coal mass and the number of pores which is influenced by mining pressure. The results provide theory reference for the research on the range of mining-induced stress and broken coal wall. PMID:24967438

Wen, Zhijie; Qu, Guanglong; Wen, Jinhao; Shi, Yongkui; Jia, Chuanyang

2014-01-01

131

Deformation Failure Characteristics of Coal Body and Mining Induced Stress Evolution Law  

PubMed Central

The results of the interaction between coal failure and mining pressure field evolution during mining are presented. Not only the mechanical model of stope and its relative structure division, but also the failure and behavior characteristic of coal body under different mining stages are built and demonstrated. Namely, the breaking arch and stress arch which influence the mining area are quantified calculated. A systematic method of stress field distribution is worked out. All this indicates that the pore distribution of coal body with different compressed volume has fractal character; it appears to be the linear relationship between propagation range of internal stress field and compressed volume of coal body and nonlinear relationship between the range of outburst coal mass and the number of pores which is influenced by mining pressure. The results provide theory reference for the research on the range of mining-induced stress and broken coal wall. PMID:24967438

Wen, Zhijie; Wen, Jinhao; Shi, Yongkui; Jia, Chuanyang

2014-01-01

132

[From symmetries to the laws of evolution. I. Chirality as a means of active media stratification].  

PubMed

Features of the hypothetical evolution of a hierarchy of chiral objects formed by active media are discussed. On the basis of experimental facts a new synergetic generalization is made: an evolving system can repeatedly broaden the spectrum of its symmetry types within one level of organization which increases its complexity and change the sign of chirality during transition to a higher level. Switching the chirality sign of macroscopic objects provides irreversibility of stratification. The known chirality of biological structures at different levels suggests that the chiral L/D-stratification should be universal and the hierarchical paths are stable and determined. A high level enantiomorph with reciprocal chirality demonstrates a wider spectrum of functionality. A fractal description of natural hierarchical systems is pointed out to be inadequate because it implicates invariance of the chirality sign of the objects at different scales. PMID:22567922

Tverdislov, V A; Sidorova, A ; Iakovenko, L V

2012-01-01

133

Computer simulation of the effect of copper on defect production and damage evolution in ferritic steels  

SciTech Connect

It has long been noticed that the effect of Cu solute atoms is important for the microstructural evolution of ferritic pressure vessel steels under neutron irradiation conditions. Despite the low concentration of Cu in steel, Cu precipitates form inside the a-Fe surrounding matrix and by impeding free dislocation motion considerably contribute to the hardening of the material. It has been suggested that Cu-rich clusters and combined Cu solute atoms-defect clusters that may act as initiating structures of further precipitates nucleate during annealing of displacement cascades. In order to assess the importance of the different mechanisms taking place during collision events in the formation and later evolution of these structures, a detailed Molecular Dynamics (MD) analysis of displacement cascades in a Fe-1.3% at. Cu binary alloy has been carried out. Cascade energies ranging from 1 to 20 keV have been simulated at temperatures of 100 and 600 K using the MDCASK code, in which the Ackland-Finnis-Sinclair many-body interatomic potential has been implemented. The behavior of metastable Cu self-interstitial atoms (SIAs) in the form of mixed Fe-Cu features is studied as well as their impact on the resulting defect structures. It is observed that above 300 K generated Cu SIAs undergo recombination with no substantial effect on the after-cascade microstructure while at 100 K Cu SIAs remain sessile and exhibit a considerable binding to interstitial and vacancy clusters, Finally, the effect that the production of vacancies via collision cascades may have on the self-diffusion of Cu solute atoms is quantitatively addressed by means of determining diffusion coefficients for Cu atoms under different microstructural conditions.

Perlado, J M; Marian, J; Lodi, D; Diaz de la Rubia, T

1999-11-28

134

THEORETICAL INVESTIGATION OF MICROSTRUCTURE EVOLUTION AND DEFORMATION OF ZIRCONIUM UNDER CASCADE DAMAGE CONDITIONS  

SciTech Connect

This work is based on our reaction-diffusion model of radiation growth of Zr-based materials proposed recently in [1]. In [1], the equations for the strain rates in unloaded pure crystal under cascade damage conditions of, e.g., neutron or heavy-ion irradiation were derived as functions of dislocation densities, which include contributions from dislocation loops, and spatial distribution of their Burgers vectors. The model takes into account the intra-cascade clustering of self-interstitial atoms and their one-dimensional diffusion; explains the growth stages, including the break-away growth of pre-annealed samples; and accounts for some striking observations, such as of negative strain in prismatic direction, and co-existence of vacancy- and interstitial-type prismatic loops. In this report, the change of dislocation densities due to accumulation of sessile dislocation loops is taken into account explicitly to investigate the dose dependence of radiation growth. The dose dependence of climb rates of dislocations is calculated, which is important for the climb-induced glide model of radiation creep. The results of fitting the model to available experimental data and some numerical calculations of the strain behavior of Zr for different initial dislocation structures are presented and discussed. The computer code RIMD-ZR.V1 (Radiation Induced Microstructure and Deformation of Zr) developed is described and attached to this report.

Barashev, Alexander V [ORNL; Golubov, Stanislav I [ORNL; Stoller, Roger E [ORNL

2012-06-01

135

Continuum-based Multiscale Computational Damage Modeling of Cementitous Composites  

E-print Network

.1.1 Prediction of the Test Result by Karsan and Jirsa (1969) ..... 73 5.1.2 Prediction of the Test Result by Sinha et al. (1964) .............. 77 5.2 Calibration of the Tensile Plasticity and Damage Evolution Laws From Loading-unloading Uniaxial...) and nominal (damaged) configurations for Sinha et al. (1964) experimental data ........................................................ 78 5.7 Comparison of the compressive loading-unloading analysis results with the experimental data by Sinha...

Kim, Sun-Myung

2011-08-08

136

Development of a viscoelastic continuum damage model for cyclic loading  

NASA Astrophysics Data System (ADS)

A previously developed spectrum model for linear viscoelastic behavior of solids is used to describe the rate-dependent damage growth of a time dependent material under cyclic loading. Through the use of the iterative solution of a special Volterra integral equation, the cyclic strain history is described. The spectrum-based model is generalized for any strain rate and any uniaxial load history to formulate the damage function. Damage evolution in the body is described through the use of a rate-type evolution law which uses a pseudo strain to express the viscoelastic constitutive equation with damage. The resulting damage function is used to formulate a residual strength model. The methodology presented is demonstrated by comparing the peak values of the computed cyclic strain history as well as the residual strength model predictions to the experimental data of a polymer matrix composite.

Sullivan, R. W.

2008-12-01

137

Propagation of continuum damage in a viscoelastic ice bar  

SciTech Connect

An initial value problem of a semi-infinite nonlinear viscoelastic bar is solved with continuum damage evolution. The evolution law of the continuum damage for a viscoelastic material is used in order to explore the propagation of two crushing mechanisms: grain boundary cracking and transgranular cracking. Using the method of characteristics, the speed of propagation is found to be dependent on the continuum damage. On the wave front, the delayed elastic strain is zero, and only the continuum damage due to the transgranular cracking evolves. A finite difference method is developed to solve the governing equations on the obtained characteristic lines, and gives a stable solution for the propagation of the stress, strain, and damage. Numerical results are obtained and discussed using the material properties of polycrystalline ice.

Shin, J.G. (Seoul National Univ. (Korea, Republic of). Dept. of Naval Architecture and Ocean Engineering); Karr, D.G. (Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Naval Architecture and Marine Engineering)

1994-05-01

138

An investigation of the effects of history dependent damage in time dependent fracture mechanics: nano-scale studies of damage evolution  

SciTech Connect

High-temperature operation of technical engineering systems is critical for system efficiency, and will be a key driver in the future US DOE energy policy. Developing an understanding of high-temperature creep and creep-fatigue failure processes is a key driver for the research work described here. The focus is on understanding the high-temperature deformation and damage development on the nano-scale (50 to 500 nm) level. The high-temperature damage development process, especially with regard to low and high cyclic loading, which has received little attention to date, is studied. Damage development under cyclic loading develops in a fashion quite different from the constant load situation. The development of analytical methodologies so that high-temperature management of new systems can be realized is the key goal of this work.

Brust, F.W. (Bud) Jr; Mohan, R.; Yang, Y.P.; Oh, J.; Katsube, N.

2002-12-01

139

Vortex Structure and Evolution within Bow Echoes. Part I: Single-Doppler and Damage Analysis of the 29 June 1998 Derecho  

Microsoft Academic Search

Single-Doppler radar along with damage observations are examined to investigate the structural evolution of vortices observed within the 29 June 1998 derecho event that propagated through southeastern Iowa into central and eastern Illinois. A total of 13 meso-g-scale vortices observed primarily at low levels (0-3 km AGL) along the leading edge of the convective system were detected by the Weather

Nolan T. Atkins; Justin M. Arnott; Ron W. Przybylinski; Ray A. Wolf; Bradley D. Ketcham

2004-01-01

140

The effects of shockwave profile shape and shock obliquity on spallation : studies of kinetics and stress state effects on damage evolution  

SciTech Connect

Shock-loading of a material in contact with a high explosive (HE) experiences a 'Taylor wave' (triangular wave) loading profile in contrast to the square-wave loading profile imparted via the impact of a flyer plate. Detailed metallographic and mlcrotextural analysis of the damage evolution in spalled Cu samples as a function of square/triangle and sweeping detonation-wave loading is presented.

Gray, George T., III [Los Alamos National Laboratory; Hull, Larry M [Los Alamos National Laboratory; Faulkner, J R [Los Alamos National Laboratory; Briggs, M E [Los Alamos National Laboratory; Cerreta, E K [Los Alamos National Laboratory; Addessio, F L [Los Alamos National Laboratory; Bourne, N K [AWE. ALDERMASTON UK

2009-06-22

141

Postbuckling Investigations of Piezoelectric Microdevices Considering Damage Effects  

PubMed Central

Piezoelectric material has been emerging as a popular building block in MEMS devices owing to its unique mechanical and electrical material properties. However, the reliability of MEMS devices under buckling deformation environments remains elusive and needs to be further explored. Based on the Talreja's tensor valued internal state damage variables as well as the Helmhotlz free energy of piezoelectric material, a constitutive model of piezoelectric materials with damage is presented. The Kachanvo damage evolution law under in-plane compressive loads is employed. The model is applied to the specific case of the postbuckling analysis of the piezoelectric plate with damage. Then, adopting von Karman's plate theory, the nonlinear governing equations of the piezoelectric plates with initial geometric deflection including damage effects under in-plane compressive loads are established. By using the finite difference method and the Newmark scheme, the damage evolution for damage accumulation is developed and the finite difference procedure for postbuckling equilibrium path is simultaneously employed. Numerical results show the postbuckling behaviors of initial flat and deflected piezoelectric plates with damage or no damage under different sets of electrical loading conditions. The effects of applied voltage, aspect ratio of plate, thick-span ratio of plate, damage as well as initial geometric deflections on the postbuckling behaviors of the piezoelectric plate are discussed. PMID:24618774

Sun, Zhigang; Wang, Xianqiao

2014-01-01

142

The Protein Folds as Platonic Forms: New Support for the Pre-Darwinian Conception of Evolution by Natural Law  

Microsoft Academic Search

Before the Darwinian revolution many biologists considered organic forms to be determined by natural law like atoms or crystals and therefore necessary, intrinsic and immutable features of the world order, which will occur throughout the cosmos wherever there is life. The search for the natural determinants of organic formthe celebrated Laws of Formwas seen as one of the major tasks

MICHAEL J. DENTON; Craig J. Marshallw; Michael Leggew

2002-01-01

143

Application of Phase Space Warping on Damage Tracking for Bearing Fault  

NASA Astrophysics Data System (ADS)

Nowadays, the significance of keeping equipment function properly each time is obvious. If equipment fails during its use, it may have disastrous consequences. Estimating remaining useful life (RUL) of equipment is a key to prevent such calamities, improve its reliability, provide security and reduce unnecessary maintenance and operational cost. The evolution and tracking of damage is the foundation of RUL predicting, and also is one of the most important content of mechanical fault diagnosis. Slow-time variable process of mechanical damage would lead the phase space reconstructed by fast-time variable vibrate signals warping. Search the dynamics characteristic law of damage evolution analysis in the phase space, and build the relationship between fast-time variable signals and slow-time variable damage, and then damage evolution tracking is possible. To validate the theory, simulation model of bearing damage evolution is built, the outer-race fault evolution signals is obtained, and the trend of evolution of degradation of bearing fault is described with Phase Space Warping (PSW) theory and Smooth Orthogonal Decomposition (SOD). The results proved the feasibility of the methodology of PSW in damage evolution tracking.

Fan, Bin; Hu, Niaoqing; Hu, Lei; Gu, Fengshou

2012-05-01

144

Comparison of Tensile Damage Evolution in Ti6A14V Joints Between Laser Beam Welding and Gas Tungsten Arc Welding  

NASA Astrophysics Data System (ADS)

The present paper studied the evolution of tensile damage in joints welded using laser beam welding (LBW) and gas tungsten arc welding (TIG) under a uniaxial tensile load. The damage evolution in the LBW joints and TIG-welded joints was studied by using digital image correlation (DIC) technology and monitoring changes in Young's modulus during tensile testing. To study the mechanism of void nucleation and growth in the LBW joints and TIG-welded joints, test specimens with various amounts of plastic deformation were analyzed using a scanning electron microscope (SEM). Compared with TIG-welded joints, LBW-welded joints have a finer microstructure and higher microhardness in the fusion zone. The SEM analysis and DIC test results indicated that the critical strain of void nucleation was greater in the LBW-welded joints than in the TIG-welded joints, while the growth rate of voids was lower in the LBW-welded joints than in the TIG-welded joints. Thus, the damage ratio in the LBW joints was lower than that in the TIG-welded joints during tensile testing. This can be due to the coarser martensitic ?' and the application of TC-1 welding rods in the TIG-welded joint.

Gao, Xiao-Long; Zhang, Lin-Jie; Liu, Jing; Zhang, Jian-Xun

2014-12-01

145

Comparison of Tensile Damage Evolution in Ti6A14V Joints Between Laser Beam Welding and Gas Tungsten Arc Welding  

NASA Astrophysics Data System (ADS)

The present paper studied the evolution of tensile damage in joints welded using laser beam welding (LBW) and gas tungsten arc welding (TIG) under a uniaxial tensile load. The damage evolution in the LBW joints and TIG-welded joints was studied by using digital image correlation (DIC) technology and monitoring changes in Young's modulus during tensile testing. To study the mechanism of void nucleation and growth in the LBW joints and TIG-welded joints, test specimens with various amounts of plastic deformation were analyzed using a scanning electron microscope (SEM). Compared with TIG-welded joints, LBW-welded joints have a finer microstructure and higher microhardness in the fusion zone. The SEM analysis and DIC test results indicated that the critical strain of void nucleation was greater in the LBW-welded joints than in the TIG-welded joints, while the growth rate of voids was lower in the LBW-welded joints than in the TIG-welded joints. Thus, the damage ratio in the LBW joints was lower than that in the TIG-welded joints during tensile testing. This can be due to the coarser martensitic ?' and the application of TC-1 welding rods in the TIG-welded joint.

Gao, Xiao-Long; Zhang, Lin-Jie; Liu, Jing; Zhang, Jian-Xun

2014-09-01

146

A model for predicting damage induced fatigue life of laminated composite structural components  

NASA Technical Reports Server (NTRS)

This paper presents a model for predicting the life of laminated composite structural components subjected to fatigue induced microstructural damage. The model uses the concept of continuum damage mechanics, wherein the effects of microcracks are incorporated into a damage dependent lamination theory instead of treating each crack as an internal boundary. Internal variables are formulated to account for the effects of both matrix cracks and internal delaminations. Evolution laws for determining the damage variables as functions of ply stresses are proposed, and comparisons of predicted damage evolution are made to experiment. In addition, predicted stiffness losses, as well as ply stresses are shown as functions of damage state for a variety of stacking sequences.

Allen, David H.; Lo, David C.; Georgiou, Ioannis T.; Harris, Charles E.

1990-01-01

147

Does Species Evolution Follow Scale Laws? First Applications of the Scale Relativity Theory to Fossil and Living-beings  

Microsoft Academic Search

We have demonstrated, using the Cantor dust method, that the statistical distribution of appearance and disappearance of rodents\\u000a species (Arvicolid rodent radiation in Europe) follows power laws strengthening the evidence for a fractal structure set.\\u000a Self-similar laws have been used as model for the description of a huge number of biological systems. With Nottale we have\\u000a shown that log-periodic behaviors

Jean Chaline

2010-01-01

148

32 CFR 842.51 - Applicable law.  

Code of Federal Regulations, 2010 CFR

...according to general principles of tort law common to the majority of American...possessions is determined according to the law of the place where the act or omission...to general principles of American tort law. (2) Apportion damages...

2010-07-01

149

Evolution  

NSDL National Science Digital Library

This virtual evolution exhibit at the University of California at Berkeley (Museum of Paleontology) combines several of the best resources we've evaluated, such as Phylogenetic Systematics and the Talk Origins Archive, among others. In addition, the Evolution Website provides information on the Theory of Evolution (with links to further information including Timeline of Evolutionary Thought; Systematics; Dinosaur Discoveries; and Vertebrate Flight) and the History of Evolutionary Thought (including dozens of biographical summaries). For educators or students interested in reviewing or learning about evolution in a historical context, this Website will be of much use.

150

Modeling Fatigue Damage in Long-Fiber Thermoplastics  

SciTech Connect

This paper applies a fatigue damage model recently developed for injection-molded long-fiber thermoplastics (LFTs) to predict the modulus reduction and fatigue lifetime of glass/polyamide 6,6 (PA6,6) specimens. The fatigue model uses a multiscale mechanistic approach to describe fatigue damage accumulation in these materials subjected to cyclic loading. Micromechanical modeling using a modified Eshelby-Mori-Tanaka approach combined with averaging techniques for fiber length and orientation distributions is performed to establish the stiffness reduction relation for the composite as a function of the microcrack volume fraction. Next, continuum damage mechanics and a thermodynamic formulation are used to derive the constitutive relations and the damage evolution law. The fatigue damage model has been implemented in the ABAQUS finite element code and has been applied to analyze fatigue of the studied glass/PA6,6 specimens. The predictions agree well with the experimental results.

Nguyen, Ba Nghiep; Kunc, Vlastimil; Bapanapalli, Satish K.

2009-10-30

151

Farmers, Ranchers, and the Railroad: The Evolution of Fence Law in the Great Plains, 1865-1900  

ERIC Educational Resources Information Center

This article is divided into three parts. The first examines specific fencing policies in Kansas, Nebraska, and other Plains states, highlighting the transformation from the "fence-out" to "fence-in" (herd laws) policies. The second part discusses the coming of the railroads to the Great Plains and the farmers and the ranchers as beneficiaries who

Kawashima, Yasuhide

2010-01-01

152

Damage zone and slip-surface evolution over ?m to km scales in high-porosity Navajo sandstone, Utah  

Microsoft Academic Search

Detailed mapping of throw variations and deformation along twokm-scale normal faults in the high-porosity Navajo sandstone, Utah, has been used to investigate fault growth in this lithology. The faults consist of one or more through-going, striated, slip-surfaces, accommodating the greater part of the offset surrounded by a damage zone consisting of deformation band clusters and short, unconnected slip-surfaces. In contrast

Z. K. Shipton; P. A. Cowie

2001-01-01

153

Pyrolytic carbon free-radical evolution and irradiation damage of polyimide under low-energy proton irradiation  

SciTech Connect

Ionization and displacement effects are basic phenomena in damage processes of materials under space-particle irradiation. In this paper, the damage behaviors were investigated on the polyimide under proton irradiation using electron paramagnetic resonance (EPR) spectra analysis and optical absorbance valuation. The results indicate that the proton irradiation induces the formation of pyrolytic carbon free-radical with a g value of 2.0025, and the population of free radicals increases with the irradiation fluence. The most important finding is that the irradiation-induced free-radical population increases linearly with the displacement damage dose, as does the optical degradation, whereas the ionization effect alone, during the irradiation, cannot induce the formation of pyrolytic carbon free radical. Furthermore, during the post storage, after irradiation, the free-radical population decreases following a sum of an exponential and a linear mode with the storage time. It is interesting that, during the post storage, the recovery of the degraded optical absorbance of the polyimide follows a similar mode to that of free radicals, and the characteristic time constant changes with the wavelength of the optical spectra.

Sun Chengyue; Wu Yiyong; Xiao Jingdong; Li Ruifeng; Yang Dezhuang; He Shiyu [National Key Lab in Materials Behaviors and Evaluation Technology in Space Environments, Harbin Institute of Technology, Harbin 150001 (China)

2011-12-15

154

Conservation laws and multiplicity evolution of spectra at energies available at the BNL Relativistic Heavy Ion Collider  

SciTech Connect

Transverse momentum distributions in ultrarelativistic heavy ion collisions carry considerable information about the dynamics of the hot system produced. Direct comparison with the same spectra from p+p collisions has proved invaluable in identifying novel features associated with the larger system, in particular, the 'jet quenching' at high momentum and the apparently much stronger collective flow dominating the spectral shape at low momentum. We point out possible hazards of ignoring conservation laws in the comparison of high- and low-multiplicity final states. We argue that the effects of energy and momentum conservation actually dominate many of the observed systematics, and that p+p collisions may be much more similar to heavy ion collisions than generally thought.

Chajecki, Zbigniew; Lisa, Mike [Department of Physics, Ohio State University, 191 West Woodruff Ave., Columbus, Ohio 43210 (United States)

2009-03-15

155

Law without Law  

E-print Network

We consider a model for spacetime in which there is an ubiquitous background Dark Energy which is the Zero Point Field. This is further modeled in terms of a Weiner process that leads to a Random or Brownian characterization. Nevertheless we are able to recover meaningful physics, very much in the spirit of Wheeler's Law without Law, that is laws emerging from an underpinning of lawlessness.

B. G. Sidharth

2007-10-21

156

Computer simulation of creep damage at crack tip in short fibre composites  

NASA Astrophysics Data System (ADS)

Creep damage at crack tip in short fibre composites has been simulated by using the finite element method (FEM). The well-known Schapery non-linear viscoelastic constitutive relationship was used to characterize time-dependent behaviour of the material. A modified recurrence equation was adopted to accelerate the iteration. Kachanov-Rabotnov's damage evolution law was employed. The growth of the damage zone with time around the crack tip was calculated and the results were shown with the so-called digit photo, which was produced by the printer.

Shuangyin, Zhang; Tsai, L. W.

1994-08-01

157

A Note on Conservation Laws Stanly Steinberg  

E-print Network

that minimizes the energy E , then this motion will satisfy Newton's law for the force determined of these forms, for example Newton's law is a force balance law, but many laws that describe the time evolution's momentum is p(t) = m v(t) where v(t) = x 0 (t) is the velocity of the particle. Newton's law says

Steinberg, Stanly

158

Evolution of different dual-use concepts in international and national law and its implications on research ethics and governance.  

PubMed

This paper provides an overview of the various dual-use concepts applied in national and international non-proliferation and anti-terrorism legislation, such as the Biological and Toxin Weapons Convention, the Chemical Weapons Convention and United Nations Security Council Resolution 1540, and national export control legislation and in relevant codes of conduct. While there is a vast literature covering dual-use concepts in particular with regard to life sciences, this is the first paper that incorporates into such discussion the United Nations Security Council Resolution 1540. In addition, recent developments such as the extension of dual-use export control legislation in the area of human rights protection are also identified and reviewed. The discussion of dual-use concepts is hereby undertaken in the context of human- and/or national-security-based approaches to security. This paper discusses four main concepts of dual use as applied today in international and national law: civilian versus military, peaceful versus non-peaceful, legitimate versus illegitimate and benevolent versus malevolent. In addition, the usage of the term to describe positive technology spin-offs between civilian and military applications is also briefly addressed. Attention is also given to the roles civil society and research ethics may play in the governance of dual-use sciences and technologies. PMID:24497004

Rath, Johannes; Ischi, Monique; Perkins, Dana

2014-09-01

159

Temporal Variation of Aerosol Properties at a Rural Continental Site and Study of Aerosol Evolution through Growth Law Analysis  

NASA Technical Reports Server (NTRS)

Aerosol size distributions were measured by a Scanning Mobility Particle Sizer (SMPS) onboard the CIRPAS Twin Otter aircraft during 16 flights at the Southern Great Plains (SGP) site in northern central Oklahoma as part of the Aerosol Intensive Operation period in May, 2003. During the same period a second SMPS was deployed at a surface station and provided continuous measurements. Combined with trace gas measurements at the SGP site and back-trajectory analysis, the aerosol size distributions provided insights into the sources of aerosols observed at the SGP site. High particle concentrations, observed mostly during daytime, were well correlated with the sulfur dioxide (SO2) mixing ratios, suggesting nucleation involving sulfuric acid is likely the main source of newly formed particles at the SGP. Aerosols within plumes originating from wildfires in Central America were measured at the surface site. Vertically compact aerosol layers, which can be traced back to forest fires in East Asia, were intercepted at altitudes over 3000 meters. Analyses of size dependent particle growth rates for four periods during which high cloud coverage was observed indicate growth dominated by volume controlled reactions. Sulfate accounts for 50% to 72% of the increase in aerosol volume concentration; the rest of the volume concentration increase was likely due to secondary organic species. The growth law analyses and meteorological conditions indicate that the sulfate was produced mainly through aqueous oxidation of SO2 in clouds droplets and hydrated aerosol particles.

Wang, Jian; Collins, Don; Covert, David; Elleman, Robert; Ferrare, Richard A.; Gasparini, Roberto; Jonsson, Haflidi; Ogren, John; Sheridan, Patrick; Tsay, Si-Chee

2006-01-01

160

Dualistic evolution of liver damage in mice triggered by a single sublethal exposure to Microcystin-LR.  

PubMed

Microcystins (MCYST) are the most frequently reported cyanotoxins in human poisoning incidents. Despite the well-described mechanism of acute and lethal injury, the sublethal effects of this toxin require further investigation. The aim of this study was to contribute to the knowledge of the variant MCYST-LR effects at sublethal doses by investigating biochemical changes and tissue damage in a murine model. For this purpose, mice were intraperitoneally injected with 45 ?g of MCYST-LR/kg body weight. Their organs were collected at 2, 8, 24, 48 or 96 h after injection. Control animals received saline solution. We detected oxidative imbalance in the liver, particularly at 8 h after exposure. Furthermore, biomarkers of liver injury were detected in high concentration in the serum of the exposed animals. Stereological analyses of the liver indicated two different phases in the intoxication process: an initial phase characterized by an increase in steatosis was followed by a second, later phase characterized by increased inflammation and hepatocyte binucleation. Formation of areas of necrosis and increased blood vessel diameter were observed throughout the experimental period. The number of hepatocytes per area unit also decreased. However, these parameters recovered over the period of exposure. MCYST accumulated in liver and was detectable until the end of the monitoring period. These results confirm the necessity for further studies of processes involved in sublethal exposure to MCYST. PMID:24593963

Mattos, L J; Valena, S S; Azevedo, S M F O; Soares, R M

2014-06-01

161

Defect interactions with stepped CeO?/SrTiO? interfaces: implications for radiation damage evolution and fast ion conduction.  

PubMed

Due to reduced dimensions and increased interfacial content, nanocomposite oxides offer improved functionalities in a wide variety of advanced technological applications, including their potential use as radiation tolerant materials. To better understand the role of interface structures in influencing the radiation damage tolerance of oxides, we have conducted atomistic calculations to elucidate the behavior of radiation-induced point defects (vacancies and interstitials) at interface steps in a model CeO2/SrTiO3 system. We find that atomic-scale steps at the interface have substantial influence on the defect behavior, which ultimately dictate the material performance in hostile irradiation environments. Distinctive steps react dissimilarly to cation and anion defects, effectively becoming biased sinks for different types of defects. Steps also attract cation interstitials, leaving behind an excess of immobile vacancies. Further, defects introduce significant structural and chemical distortions primarily at the steps. These two factors are plausible origins for the enhanced amorphization at steps seen in our recent experiments. The present work indicates that comprehensive examination of the interaction of radiation-induced point defects with the atomic-scale topology and defect structure of heterointerfaces is essential to evaluate the radiation tolerance of nanocomposites. Finally, our results have implications for other applications, such as fast ion conduction. PMID:24852551

Dholabhai, Pratik P; Aguiar, Jeffery A; Misra, Amit; Uberuaga, Blas P

2014-05-21

162

Cumulative creep damage for polycarbonate and polysulfone  

NASA Technical Reports Server (NTRS)

The literature for creep to failure cumulative damage laws are reviewed. Creep to failure tests performed on polycarbonate and polysulfone under single and two step loadings are discussed. A cumulative damage law or modified time fraction rule is developed using a power law for transient creep response as the starting point. Experimental results are approximated well by the new rule. Damage and failure mechanisms associated with the two materials are suggested.

Zhang, M.; Brinson, H. F.

1985-01-01

163

A Transversely Isotropic Damage Model for Boom Clay  

NASA Astrophysics Data System (ADS)

Boom clay can be considered as a transversely isotropic geomaterial. However, due to lack of experimental evidence and data base, it is still difficult to describe the transversely isotropic plastic behavior of this argillaceous rock. In this paper, we present first, by means of an experimental approach, the main features of the mechanical properties of Boom clay. Then, combining the transversely isotropic elastic model and the modified Mohr-Coulomb criterion, a suitable constitutive model is introduced so as to fully describe the mechanical behavior of the studied material, in which, an elastic damage law which takes into consideration, the transversely isotropic effect, a plastic hardening law and a plastic damage law were introduced to describe the nonlinear elastic, hardening and softening behavior of Boom clay. As a preliminary step, the evolution law of both elastic moduli and Poisson's ratio during the elastic stage was obtained by direct analysis of the test data. The synchronism of the elastic damage in both transversal and axial directions was proved by this method. Some of the parameters of the model in the elastic stage were also determined by direct analysis method and further verified by back analysis. Other unknown parameters in the model were determined by back analysis.

Yu, H. D.; Chen, W. Z.; Li, X. L.; Sillen, X.

2014-01-01

164

Law Courses Coventry Law School  

E-print Network

Law Courses Coventry Law School #12;Contents 51 Coventry Law School Moot Room Welcome to Coventry Law School At Coventry Law School we are looking to provide you with a range of innovative courses that will equip you for your future career. The Law School is staffed by over twenty, well qualified, full

Low, Robert

165

Prediction of Damage in A Randomly Oriented Short-Fiber Composite Plate Containing A Central Hole  

SciTech Connect

A micro-macro approach to matrix cracking in randomly oriented short-fiber composites is used in this paper for the damage and failure analysis of a random glass/epoxy plate containing a central hole under tensile loading. At the micro-scale, the virgin and reduced elastic properties of the composite are computed using micromechanical models and are then averaged over all possible orientations and weighted by an orientation distribution function. Next, the macroscopic response is performed by means of a continuum damage mechanics formulation in which the damage evolution law is obtained using a damage threshold function and the concepts of thermodynamic of continuous media. Damage accumulations leading to initiation and propagation of a macroscopic crack are modeled using a vanishing element technique.

Nguyen, Ba Nghiep; Khaleel, Mohammad A.; Bathe, K.-J.

2003-01-01

166

Water, law, science  

SciTech Connect

In a world with water resources severely impacted bytechnology, science must actively contribute to water law. To this end,this paper is an earth scientist s attempt to comprehend essentialelements of water law, and to examine their connections to science.Science and law share a common logical framework of starting with apriori prescribed tenets, and drawing consistent inferences. In science,observationally established physical laws constitute the tenets, while inlaw, they stem from social values. The foundations of modern water law inEurope and the New World were formulated nearly two thousand years ago byRoman jurists who were inspired by Greek philosophy of reason.Recognizing that vital natural elements such as water, air, and the seawere governed by immutable natural laws, they reasoned that theseelements belonged to all humans, and therefore cannot be owned as privateproperty. Legally, such public property was to be governed by jusgentium, the law of all people or the law of all nations. In contrast,jus civile or civil law governed private property. Remarkably, jusgentium continues to be relevant in our contemporary society in whichscience plays a pivotal role in exploiting vital resources common to all.This paper examines the historical roots of modern water law, followstheir evolution through the centuries, and examines how the spirit ofscience inherent in jus gentium is profoundly influencing evolving waterand environmental laws in Europe, the United States and elsewhere. In atechnological world, scientific knowledge has to lie at the core of waterlaw. Yet, science cannot formulate law. It is hoped that a philosophicalunderstanding of the relationships between science and law willcontribute to their constructively coming together in the service ofsociety.

Narasimhan, T.N.

2007-10-17

167

Cumulative creep damage for polycarbonate and polysulfone  

NASA Technical Reports Server (NTRS)

Creep to failure tests performed on polycarbonate and polysulfone under single and two step loadings are discussed. A cumulative damage law or modified time fraction rule is developed using a power law for transient creep response as the starting point. Experimental results are approximated well by the new rule. Damage and failure mechanisms associated with the two materials are suggested.

Zhang, M. J.; Straight, M. R.; Brinson, H. F.

1985-01-01

168

A model for high temperature creep of single crystal superalloys based on nonlocal damage and viscoplastic material behavior  

NASA Astrophysics Data System (ADS)

A model for high temperature creep of single crystal superalloys is developed, which includes constitutive laws for nonlocal damage and viscoplasticity. It is based on a variational formulation, employing potentials for free energy, and dissipation originating from plasticity and damage. Evolution equations for plastic strain and damage variables are derived from the well-established minimum principle for the dissipation potential. The model is capable of describing the different stages of creep in a unified way. Plastic deformation in superalloys incorporates the evolution of dislocation densities of the different phases present. It results in a time dependence of the creep rate in primary and secondary creep. Tertiary creep is taken into account by introducing local and nonlocal damage. Herein, the nonlocal one is included in order to model strain localization as well as to remove mesh dependence of finite element calculations. Numerical results and comparisons with experimental data of the single crystal superalloy LEK94 are shown.

Trinh, B. T.; Hackl, K.

2014-07-01

169

Damage modeling for durability of composites  

NASA Astrophysics Data System (ADS)

The objective of this thesis is to provide a framework for predicting the durability and damage tolerance of composite structures. Cross-ply laminate configurations under tension-tension fatigue are the focus of this study. A mechanistic model is presented that analyzes laminates damaged under fatigue loading by incorporating both transverse matrix cracks in the 90sp layer and interlaminar delaminations along the 0sp-90sp interface. A variational method using the principle of minimum complementary energy is employed to predict the stress states in the damaged laminate. Damage progression under cycling is explained by assuming frictional sliding along the delaminated interface. Two different distributions of shear stress are considered to exist along this interface and the relative merits of the two shear stress distributions are discussed. A finite element model is presented to verify the stress fields obtained from the damage model and results from the finite element analysis are seen to agree with the damage model predictions. A power-law type relationship is assumed to account for delamination growth during cycling and subsequent transverse crack evolution with number of cycles is predicted. It is seen that the saturation crack densities depend not only on the physical and mechanical properties of the laminate but also on the applied stresses at which the laminate is cycled. The crack densities obtained under fatigue are much higher than those under quasi-static loading at the same maximum stress levels. Also, changes in residual Young's modulus and Poisson's ratio are predicted. Finally, a laminate failure criterion is proposed and the fatigue lives of laminates under various applied stresses are presented in the form of a fatigue life diagram. The fatigue life predictions show good agreement with experimental data.

Akshantala, Nagendra Prasad Venkata

170

Lawful Policing  

Microsoft Academic Search

Police compliance with the law is one of the most important aspects of a democratic society. Americans expect the police to enforce laws to promote safety and to reduce crime, victimization, and fear, but no one believes that the police should have unlimited power to do so. We expect police to enforce laws fairly according to law and rules that

Wesley G. Skogan; Tracey L. Meares

2004-01-01

171

Putting Law into Ethics.  

ERIC Educational Resources Information Center

The evolution of ethics in law is followed from the harshness of caveat emptor to the humanistic ethics of the 1970s, including a renewal of formal ethics in the post-Watergate era. The impact on universities and individual disciplines of legalizing ethical conduct is examined cautiously. (JMF)

Lieberman, Jethro K.

1979-01-01

172

32 CFR 537.5 - Applicable law.  

Code of Federal Regulations, 2010 CFR

...omissions must constitute a tort as determined by the law of place of occurrence...jurisdictions where the no-fault law permits recovery. Where the tort is not complete within...extent and nature of the tort. However, as to what law of damages is...

2010-07-01

173

32 CFR 537.5 - Applicable law.  

Code of Federal Regulations, 2013 CFR

...extent and nature of the tort. However, as to what law of damages is applicable, Maryland or Virginia depecage (choice of law) theory may apply. For example, if the flight originated in Indiana and the destination was Virginia, the conflict law of both...

2013-07-01

174

Progressive Damage Analysis of Laminated Composite (PDALC)-A Computational Model Implemented in the NASA COMET Finite Element Code  

NASA Technical Reports Server (NTRS)

A method for analysis of progressive failure in the Computational Structural Mechanics Testbed is presented in this report. The relationship employed in this analysis describes the matrix crack damage and fiber fracture via kinematics-based volume-averaged variables. Damage accumulation during monotonic and cyclic loads is predicted by damage evolution laws for tensile load conditions. The implementation of this damage model required the development of two testbed processors. While this report concentrates on the theory and usage of these processors, a complete list of all testbed processors and inputs that are required for this analysis are included. Sample calculations for laminates subjected to monotonic and cyclic loads were performed to illustrate the damage accumulation, stress redistribution, and changes to the global response that occur during the load history. Residual strength predictions made with this information compared favorably with experimental measurements.

Lo, David C.; Coats, Timothy W.; Harris, Charles E.; Allen, David H.

1996-01-01

175

A damage mechanics based general purpose interface/contact element  

NASA Astrophysics Data System (ADS)

Most of the microelectronics packaging structures consist of layered substrates connected with bonding materials, such as solder or epoxy. Predicting the thermomechanical behavior of these multilayered structures is a challenging task in electronic packaging engineering. In a layered structure the most complex part is always the interfaces between the strates. Simulating the thermo-mechanical behavior of such interfaces, is the main theme of this dissertation. The most commonly used solder material, Pb-Sn alloy, has a very low melting temperature 180spC, so that the material demonstrates a highly viscous behavior. And, creep usually dominates the failure mechanism. Hence, the theory of viscoplasticity is adapted to describe the constitutive behavior. In a multilayered assembly each layer has a different coefficient of thermal expansion. Under thermal cycling, due to heat dissipated from circuits, interfaces and interconnects experience low cycle fatigue. Presently, the state-of-the art damage mechanics model used for fatigue life predictions is based on Kachanov (1986) continuum damage model. This model uses plastic strain as a damage criterion. Since plastic strain is a stress path dependent value, the criterion does not yield unique damage values for the same state of stress. In this dissertation a new damage evolution equation based on the second law of thermodynamic is proposed. The new criterion is based on the entropy of the system and it yields unique damage values for all stress paths to the final state of stress. In the electronics industry, there is a strong desire to develop fatigue free interconnections. The proposed interface/contact element can also simulate the behavior of the fatigue free Z-direction thin film interconnections as well as traditional layered interconnects. The proposed interface element can simulate behavior of a bonded interface or unbonded sliding interface, also called contact element. The proposed element was verified against laboratory test data presented in the literature. The results demonstrate that the proposed element and the damage law perform very well. The most important scientific contribution of this dissertation is the proposed damage criterion based on second law of thermodynamic and entropy of the system. The proposed general purpose interface/contact element is another contribution of this research. Compared to the previous adhoc interface elements proposed in the literature, the new one is, much more powerful and includes creep, plastic deformations, sliding, temperature, damage, cyclic behavior and fatigue life in a unified formulation.

Yan, Chengyong

176

Physical law not natural selection as the major determinant of biological complexity in the subcellular realm: new support for the pre-Darwinian conception of evolution by natural law  

Microsoft Academic Search

Before Darwin many biologists considered organic forms to be immutable natural forms or types which like inorganic forms such as atoms or crystals are part of a changeless world order and determined by physical law. Adaptations were viewed as secondary modifications of these crystal like abstract afunctional givens of physics. We argue here that much of the emerging picture of

Michael J. Denton; Peter K. Dearden; Stephen J. Sowerby

2003-01-01

177

Progressive Damage Analysis of Laminated Composite (PDALC) (A Computational Model Implemented in the NASA COMET Finite Element Code). 2.0  

NASA Technical Reports Server (NTRS)

A method for analysis of progressive failure in the Computational Structural Mechanics Testbed is presented in this report. The relationship employed in this analysis describes the matrix crack damage and fiber fracture via kinematics-based volume-averaged damage variables. Damage accumulation during monotonic and cyclic loads is predicted by damage evolution laws for tensile load conditions. The implementation of this damage model required the development of two testbed processors. While this report concentrates on the theory and usage of these processors, a complete listing of all testbed processors and inputs that are required for this analysis are included. Sample calculations for laminates subjected to monotonic and cyclic loads were performed to illustrate the damage accumulation, stress redistribution, and changes to the global response that occurs during the loading history. Residual strength predictions made with this information compared favorably with experimental measurements.

Coats, Timothy W.; Harris, Charles E.; Lo, David C.; Allen, David H.

1998-01-01

178

LAW, HISTORY, &LAW, HISTORY, &LAW, HISTORY, & CULTURECULTURECULTURE  

E-print Network

theoretical and analytical perspectives on ethical, political, and social issues relevant to law by exploring from a historical perspective; explores the interaction of law, culture, and politics from of departments within USC Dornsife, including Classics, History, Philosophy, and Political Science. Center

Rohs, Remo

179

Limit laws for Zipf's law  

NASA Astrophysics Data System (ADS)

In this communication we establish stochastic limit laws leading from Zipf's law to Pareto's and Heaps' laws. We consider finite ensembles governed by Zipf's law and study their asymptotic statistics as the ensemble size tends to infinity. A Lorenz-curve analysis establishes three types of limit laws for the ensembles' statistical structure: 'communist', 'monarchic', and Paretian. Further considering a dynamic setting in which the ensembles grow stochastically in time, a functional central limit theorem analysis establishes a Gaussian approximation for the ensembles' stochastic growth. The Gaussian approximation provides a generalized and corrected formulation of Heaps' law.

Eliazar, Iddo

2011-01-01

180

Radiation Laws  

NSDL National Science Digital Library

This site lists physical laws that describe radiation. Topics covered include the Plank Radiation Law, and the Wien and Stefan-Boltzmann Laws. The site also features a table summarizing the blackbody temperatures necessary to give a peak for emitted radiation in various regions of the spectrum, and three Java applets illustrating important properties of blackbody radiation.

Astronomy, Department O.; Knoxville, University O.

181

Tornado Damage!  

NSDL National Science Digital Library

Students learn about tornadoes, the damage they cause, and how to rate tornadoes. Specifically, students investigate the Enhanced Fujita Damage Scale of tornado intensity, and use it to complete a mock engineering analysis of damage caused by a tornado. Additional consideration is given to tornado warning systems and how these systems can be improved to be safer. Lastly, students learn basic tornado safety procedures.

Integrated Teaching And Learning Program

182

Environmental Laws  

NSDL National Science Digital Library

The Environmental Protection Agency (EPA) has compiled a list of the seventeen major environmental laws which govern their agency and the programs they administer. Users can link to summaries or the full-text version of each law, provided, for the most part, by Cornell University. Those new to the subject may want to visit the Introduction to Laws and Regulations section, which explains how environmental laws come into being. Additional sections of the site--Regulations and Proposed Rules, Codified Regulations, and Current Legislation and Laws--link to further information such as Federal Register documents issued by EPA and the Code of Federal Regulations database.

United States. Environmental Protection Agency.

183

SCHOOL OF LAW 120 School of Law  

E-print Network

SCHOOL OF LAW #12;120 School of Law SCHOOL OF LAW School of Law, Admission Office 530-752-6477; admissions@law.ucdavis.edu, http://www.law.ucdavis.edu The University of California Davis School of Law supportive atmosphere, law students are pro- vided a comprehensive modern law school curriculum taught

California at Davis, University of

184

The fractal structure of evolution  

Microsoft Academic Search

The claim is made that everything we know of, including our physical laws and space with its symmetries, occurred through evolution. Each evolution is a complete component of the preceding evolution. Every evolution is subject to the same mechanisms. The fact that all evolutions have self-similar structures and are encapsuled in one another calls to mind Mandelbrot's fractal geometry.

Gerd Binnig

1989-01-01

185

Darwin's laws.  

PubMed

There is widespread agreement among contemporary philosophers of biology and philosophically-minded biologists that Darwin's insights about the intrusion of chance processes into biological regularities undermines the possibility of there being biological laws. Darwin made references to "designed laws." He also freely described some laws as having exceptions. This paper provides a philosophical analysis of the notion of scientific laws that was dominant in Darwin's time, and in all probability the one which he inherited. The analysis of laws is then used to show how it could have been natural for Darwin to believe in designed laws that had exceptions, and to highlight the continuity between the metaphysics of pre-Darwinian, Darwinian, and contemporary biological science. One important result is the removal of one motivation for the anti-laws sentiment in philosophy and biology. PMID:22326096

Haufe, Chris

2012-03-01

186

Physical law not natural selection as the major determinant of biological complexity in the subcellular realm: new support for the pre-Darwinian conception of evolution by natural law.  

PubMed

Before Darwin many biologists considered organic forms to be immutable natural forms or types which like inorganic forms such as atoms or crystals are part of a changeless world order and determined by physical law. Adaptations were viewed as secondary modifications of these 'crystal like' abstract afunctional 'givens of physics.' We argue here that much of the emerging picture of biological order in the subcellular realm resembles closely the pre-Darwinian conception of nature. We point out that in the subcellular realm, between nano and micrometers, physical law necessarily plays a far more significant role in organizing matter than in the familiar 'Darwinian world' between millimeters and meters (where matter can be arranged into almost any contingent artifactual arrangement we choose, as witness Lego toys, watches or jumbo jets). Consequently, when deploying matter into complex structures in the subcellular realm the cell must necessarily make extensive use of natural forms-such as the protein and RNA folds, microtubular forms and tensegrity structures-which like atoms or crystals self-organize under the direction of physical law into what are essentially 'pre-Darwinian' afunctional abstract molecular architectures in which adaptations are trivial secondary modifications of what are evidently primary givens of physics. PMID:14563569

Denton, Michael J; Dearden, Peter K; Sowerby, Stephen J

2003-10-01

187

Darwin's evolutionary philosophy: The laws of change  

Microsoft Academic Search

The philosophical or metaphysical architecture of Darwin's theory of evolution by natural selection is analyzed and diflussed. It is argued that natural selection was for Darwin a paradigmatic case of a natural law of change an exemplar of what Ghiselin (1969) has called selective retention laws. These selective retention laws lie at the basis of Darwin's revolutionary world view.

Edward S. Reed

1978-01-01

188

A continuous low cycle fatigue damage model and its application in engineering materials  

Microsoft Academic Search

In this study, the low cycle fatigue (LCF) damage evolution of the engineering materials is studied by use of continuum damage mechanics (CDM) theory. Based on thermodynamics, on a continuum damage variable, D, and on the effective stress concept, a continuum damage model of isotropic LCF is derived and is used to analyze the strain-controlled LCF damage evolution of steam

Xiaohua Yang; Nian Li; Zhihao Jin; Tiejun Wang

1997-01-01

189

Law 302.  

ERIC Educational Resources Information Center

This publication outlines a law course intended as part of a business education program in the secondary schools of Manitoba, Canada. The one credit course of study should be taught over a period of 110-120 hours of instruction. It provides students with an introduction to the principles, practices, and consequences of law with regard to torts,

Manitoba Dept. of Education, Winnipeg.

190

Prediction of Forming Limits Based on a Coupled Approach Between Anisotropic Damage and Necking Models  

NASA Astrophysics Data System (ADS)

This article presents an integrated approach for localized necking and failure prediction in sheet metal forming processes, based on the coupling between the anisotropic damage evolution law proposed by Lemaitre [1] and the modified maximum force criterion (MMFC) proposed by Hora et al. [2]. To illustrate the essential features of the coupled approach, an aluminum alloy has been selected and numerical predictions have been compared with experimental forming limits, obtained for both linear strain paths evolutions. Numerical results show that the introduction of the softening behavior, caused by the increase of damage, into the necking criterion can play a significant role in triggering local necking, providing an improved prediction of the necking occurrence together with the capability of performing calculations of limit strains when they are governed by fracture rather than by local necking.

Teixeira, P.; Csar de S, J. M. A.; Santos, A. D.; Pires, F. M. A.; Barata da Rocha, A.

2010-06-01

191

Partition coefficients for REE between garnets and liquids - Implications of non-Henry's Law behaviour for models of basalt origin and evolution  

NASA Technical Reports Server (NTRS)

An experimental investigation of Ce, Sm and Tm rare earth element (REE) partition coefficients between coexisting garnets (both natural and synthetic) and hydrous liquids shows that Henry's Law may not be obeyed over a range of REE concentrations of geological relevance. Systematic differences between the three REE and the two garnet compositions may be explained in terms of the differences between REE ionic radii and those of the dodecahedral site into which they substitute, substantiating the Harrison and Wood (1980) model of altervalent substitution. Model calculations demonstrate that significant variation can occur in the rare earth contents of melts produced from a garnet lherzolite, if Henry's Law partition coefficients do not apply for the garnet phase.

Harrison, W. J.

1981-01-01

192

Employment Law  

NSDL National Science Digital Library

Ross Runkel is a retired professor of law, and given his long experience with employment and labor law, it seems quite natural that he would be the founder of the site, Employment Law. Along with a team of other equally qualified professionals, he has created this site to serve as a clearinghouse of material about the world of employment law and its many facets. First time visitors may wish to check out his employment law or arbitration blogs, then move on to one of the most popular features, a list of recent and pending cases in the field that have been heard before the US Supreme Court. Additionally, the âArticlesâ area contains pieces authored by Runkel and others, including a piece on how to find an employment lawyer and several timely pieces on the National Labor Relations Board.

Runkel, Ross, 1939-

193

Evolution of damage in the lens after in vivo close to threshold exposure to UV-B radiation: cytomorphological study of apoptosis.  

PubMed

The purpose of the present study was to investigate cataractogenesis and recovery of lens damage after in vivo close to threshold ultraviolet (UV)-B radiation around 300 nm. Eighty six-week-old albino Sprague-Dawley rats were familiarized to a rat restrainer five days prior to exposure. Groups of non-anesthetized rats were exposed unilaterally to 8 kJ/m(2) UVR-300 nm. The animals were sacrificed at 1, 7, 48 and 336h following exposure. The lenses were extracted for imaging of dark-field lens macro anatomy and measurement of intensity of forward lens light scattering to quantify lens opacities. Three exposed lenses and one non-exposed lens from each time interval were examined with light and transmission electron microscopy (TEM). Macro anatomy and lens light scattering revealed that all contralateral non-exposed lenses were clear. The degree of lens opacity (difference in lens light scattering between exposed and non-exposed lenses) increased during the 336h, reaching a plateau towards the end of the observation period. Light microscopy and TEM demonstrated that apoptotic features appeared in the epithelium already 1h after UVR exposure, and small vacuoles were seen in the outer cortex. Epithelial damage occurs during the first 48h after exposure and is followed by regenerative repair at 336h post-exposure. Apoptotic epithelial cells were phagocytized by adjacent epithelial cells. Cortical fiber cells exhibited increasing damage throughout the observation period without any clear repair after 336h. In conclusion, acute UVR-induced cataract is partly a reversible. Lens epithelium is a primary target for UVR exposure. Damage to cortical fiber cells remained irreversible. PMID:20599969

Galichanin, Konstantin; Lfgren, Stefan; Bergmanson, Jan; Sderberg, Per

2010-09-01

194

Elastic-Plastic Constitutive Equation of WC-Co Cemented Carbides with Anisotropic Damage  

NASA Astrophysics Data System (ADS)

Elastic-plastic constitutive equation of WC-Co cemented carbides with anisotropic damage is proposed to predict a precise service life of cold forging tools. A 2nd rank symmetric tensor damage tensor is introduced in order to express the stress unilaterality; a salient difference in uniaxial behavior between tension and compression. The conventional framework of irreversible thermodynamics is used to derive the constitutive equation. The Gibbs potential is formulated as a function of stress, damage tensor, isotropic hardening variable and kinematic hardening variable. The elastic-damage constitutive equation, conjugate forces of damage, isotropic hardening and kinematic hardening variable is derived from the potential. For the kinematic hardening variable, the superposition of three kinematic hardening laws is employed in order to improve the cyclic behavior of the material. For the evolution equation of the damage tensor, the damage is assumed to progress by fracture of the Co matrix WC particle interface and by the mechanism of fatigue, i.e. the accumulation of microscopic plastic strain in matrix and particles. By using the constitutive equations, calculation of uniaxial tensile and compressive test is performed and the results are compared with the experimental ones in the literature. Furthermore, finite element analysis on cold forward extrusion was carried out, in which the proposed constitutive equation was employed as die insert material.

Hayakawa, Kunio; Nakamura, Tamotsu; Tanaka, Shigekazu

2007-05-01

195

Elastic-Plastic Constitutive Equation of WC-Co Cemented Carbides with Anisotropic Damage  

SciTech Connect

Elastic-plastic constitutive equation of WC-Co cemented carbides with anisotropic damage is proposed to predict a precise service life of cold forging tools. A 2nd rank symmetric tensor damage tensor is introduced in order to express the stress unilaterality; a salient difference in uniaxial behavior between tension and compression. The conventional framework of irreversible thermodynamics is used to derive the constitutive equation. The Gibbs potential is formulated as a function of stress, damage tensor, isotropic hardening variable and kinematic hardening variable. The elastic-damage constitutive equation, conjugate forces of damage, isotropic hardening and kinematic hardening variable is derived from the potential. For the kinematic hardening variable, the superposition of three kinematic hardening laws is employed in order to improve the cyclic behavior of the material. For the evolution equation of the damage tensor, the damage is assumed to progress by fracture of the Co matrix - WC particle interface and by the mechanism of fatigue, i.e. the accumulation of microscopic plastic strain in matrix and particles. By using the constitutive equations, calculation of uniaxial tensile and compressive test is performed and the results are compared with the experimental ones in the literature. Furthermore, finite element analysis on cold forward extrusion was carried out, in which the proposed constitutive equation was employed as die insert material.

Hayakawa, Kunio; Nakamura, Tamotsu; Tanaka, Shigekazu [Department of Mechanical Engineering, Shizuoka University, 3-5-1 Johoku, Hamamatsu 432-8561 (Japan)

2007-05-17

196

Full-scale prestress loss monitoring of damaged RC structures using distributed optical fiber sensing technology.  

PubMed

For the safety of prestressed structures, prestress loss is a critical issue that will increase with structural damage, so it is necessary to investigate prestress loss of prestressed structures under different damage scenarios. Unfortunately, to date, no qualified techniques are available due to difficulty for sensors to survive in harsh construction environments of long service life and large span. In this paper, a novel smart steel strand based on the Brillouin optical time domain analysis (BOTDA) sensing technique was designed and manufactured, and then series of tests were used to characterize properties of the smart steel strands. Based on prestress loss principle analysis of damaged structures, laboratory tests of two similar beams with different damages were used to verify the concept of full-scale prestress loss monitoring of damaged reinforced concrete (RC) beams by using the smart steel strands. The prestress losses obtained from the Brillouin sensors are compared with that from conventional sensors, which provided the evolution law of prestress losses of damaged RC beams. The monitoring results from the proposed smart strand can reveal both spatial distribution and time history of prestress losses of damaged RC beams. PMID:22778590

Lan, Chunguang; Zhou, Zhi; Ou, Jinping

2012-01-01

197

The Law and Neuroscience Project  

E-print Network

examining implicit juror bias, the effects of early prefrontal cortex damage, and drug addiction and the law on evidence obtained from a "Brain Electrical Oscillations Signature" (BEOS) test. This test claims to use patterns of brain activation to determine whether or not a person has experiential knowledge

Wagner, Anthony

198

Postgraduate Study in Law School of Law  

E-print Network

Postgraduate Study in Law School of Law #12;PostgraduateProgrammes in Law The School of Law law study at UC Postgraduate study in law gives you the opportunity to: · Gain a highly-regarded postgraduate law qualification · Develop in-depth expertise in particular fields of legal specialisation

Hickman, Mark

199

Guass's Law  

NSDL National Science Digital Library

A Keynote Presentation exported as a clickable Quicktime movie. Gauss's Law is demonstrated in this presentation. Utilizing an insulated sphere enclosed in a spherical conducting shell. All equations are fully developed.

Mr. Tony DiMauro

2009-01-12

200

Florida Law  

NSDL National Science Digital Library

This fine collection from the University of Florida's George A. Smathers Libraries documents the laws and legal heritage of Florida. It has digitized texts from the holdings of the University of Florida's Lawton Chiles Legal Information Center and the P. K. Yonge Library of Florida History as well as other sources. This omnibus collection features the Journal of the Florida House of Representatives, a variety of general texts on Florida laws, and the Florida Water Law collection. This last collection is particularly fascinating as it brings together over 7,000 documents related to long-term water management plans across the Sunshine State. Moving on, the Florida Historical Legal Documents section of the site contains primary source materials that survey changes in Florida law from 1822 through 1845, when the area became a state. Finally, the House Journal section brings together the official record of actions taken by the House and its committees.

2011-01-01

201

32 CFR 750.33 - Damages.  

Code of Federal Regulations, 2010 CFR

...GENERAL CLAIMS REGULATIONS Federal Tort Claims Act 750.33 Damages...measure of damages is determined by the law of the place where the act or omission...services as the result of the alleged tort. The cost of these services...

2010-07-01

202

Property Evaluation and Damage Evolution of Environmental Barrier Coatings and Environmental Barrier Coated SiC/SiC Ceramic Matrix Composite Sub-Elements  

NASA Technical Reports Server (NTRS)

This paper describes recent development of environmental barrier coatings on SiC/SiC ceramic matrix composites. The creep and fatigue behavior at aggressive long-term high temperature conditions have been evaluated and highlighted. Thermal conductivity and high thermal gradient cyclic durability of environmental barrier coatings have been evaluated. The damage accumulation and complex stress-strain behavior environmental barrier coatings on SiCSiC ceramic matrix composite turbine airfoil subelements during the thermal cyclic and fatigue testing of have been also reported.

Zhu, Dongming; Halbig, Michael; Jaskowiak, Martha; Hurst, Janet; Bhatt, Ram; Fox, Dennis S.

2014-01-01

203

Newton's Laws  

NSDL National Science Digital Library

This set of four educational wall-sheets includes Newton's Three Laws and the Law of Gravitation. They include activities that are designed to be displayed as a set on classroom walls. The pre-activity reading featuring the Swift satellite and most activities can be used in middle-school classrooms. Optional extension activities are suitable for advanced middle-school students and students in ninth grade.

Cominsky, Lynn

2010-01-01

204

TRANSBOUNDARY GROUNDWATER AND INTERNATIONAL LAW: PAST PRACTICES AND CURRENT IMPLICATIONS  

E-print Network

TRANSBOUNDARY GROUNDWATER AND INTERNATIONAL LAW: PAST PRACTICES AND CURRENT IMPLICATIONS By Kyoko........................................................................................................................................ 1 2. The Notion of Transboundary Groundwater................................................................................... 3 3. Evolution of International Groundwater Management in Environmental Law

Wolf, Aaron

205

The Role of Elastic and Plastic Anisotropy of Sn in Recrystallization and Damage Evolution During Thermal Cycling in SAC305 Solder Joints  

SciTech Connect

Because failures in lead-free solder joints occur at locations other than the most highly shear-strained regions, reliability prediction is challenging. To gain physical understanding of this phenomenon, physically based understanding of how elastic and plastic deformation anisotropy affect microstructural evolution during thermomechanical cycling is necessary. Upon solidification, SAC305 (Sn-3.0Ag-0.5Cu) solder joints are usually single or tricrystals. The evolution of microstructures and properties is characterized statistically using optical and orientation imaging microscopy. In situ synchrotron x-ray measurements during thermal cycling are used to examine how crystal orientation and thermal cycling history change strain history. Extensive characterization of a low-stress plastic ball grid array (PBGA) package design at different stages of cycling history is compared with preliminary experiments using higher-stress package designs. With time and thermal history, microstructural evolution occurs mostly from continuous recrystallization and particle coarsening that is unique to each joint, because of the specific interaction between local thermal and displacement boundary conditions and the strong anisotropic elastic, plastic, expansion, and diffusional properties of Sn crystals. The rate of development of recrystallized microstructures is a strong function of strain and aging. Cracks form at recrystallized (random) boundaries, and then percolate through recrystallized regions. Complications arising from electromigration and corrosion are also considered.

Bieler, Thomas R.; Zhou, Bite; Blair, Lauren; Zamiri, Amir; Darbandi, Payam; Pourboghrat, Farhang; Lee, Tae-Kyu; Liu, Kuo-Chuan (Michigan); (Cisco)

2013-04-08

206

Sun Damage  

MedlinePLUS

newsletter | contact Share | Sun Damage A A A The sun has a profound effect over years of exposure on the skin, causing premature ... changes. Exposure to ultraviolet (UV) light from the sun accounts for most premature skin aging. Many skin ...

207

Consequences of the Thermal Transient on the Evolution of the Damaged Zone Around a Repository for Heat-Emitting High-Level Radioactive Waste in a Clay Formation: a Performance Assessment Perspective  

NASA Astrophysics Data System (ADS)

A proper evaluation of the perturbations of the host rock induced by the excavation and the emplacement of exothermic wastes is essential for the assessment of the long-term safety of high-level radioactive waste disposals in clay formations. The impact of the thermal transient on the evolution of the damaged zone (DZ) has been explored in the European Commission project TIMODAZ (thermal impact on the damaged zone around a radioactive waste disposal in clay host rocks, 2006-2010). This paper integrates the scientific results of the TIMODAZ project from a performance assessment (PA) point of view, showing how these results support and justify key PA assumptions and the values of PA model parameters. This paper also contextualises the significance of the thermal impact on the DZ from a safety case perspective, highlighting how the project outcomes result into an improved understanding of the thermo-hydro-mechanical behaviour of the clay host rocks. The results obtained in the TIMODAZ project strengthen the assessment basis of the safety evaluation of the current repository designs. There was no evidence throughout the TIMODAZ experimental observations of a temperature-induced additional opening of fractures nor of a significant permeability increase of the DZ. Instead, thermally induced plasticity, swelling and creep seem to be beneficial to the sealing of fractures and to the recovery of a very low permeability in the DZ, close to that of an undisturbed clay host rock. Results from the TIMODAZ project indicate that the favourable properties of the clay host rock, which guarantee the effectiveness of the safety functions of the repository system, are expected to be maintained after the heating-cooling cycle. Hence, the basic assumptions usually made in PA calculations so far are expected to remain valid, and the performance of the system should not be affected in a negative way by the thermal evolution of the DZ around a radioactive waste repository in clay host rock.

Yu, Li; Weetjens, Eef; Sillen, Xavier; Vietor, Tim; Li, Xiangling; Delage, Pierre; Labiouse, Vincent; Charlier, Robert

2014-01-01

208

Patenting Human Evolution  

E-print Network

to thorough analysis and debate prior to the imminent arrival of human genetic enhancement technologies. Otherwise, patent law may drive human evolution in directions either unplanned - or worse - undesired....

Torrance, Andrew W.

2008-06-01

209

MULTI-WAVELENGTH OBSERVATIONS OF THE SPATIO-TEMPORAL EVOLUTION OF SOLAR FLARES WITH AIA/SDO. I. UNIVERSAL SCALING LAWS OF SPACE AND TIME PARAMETERS  

SciTech Connect

We extend a previous statistical solar flare study of 155 GOES M- and X-class flares observed with AIA/SDO to all seven coronal wavelengths (94, 131, 171, 193, 211, 304, and 335 ) to test the wavelength dependence of scaling laws and statistical distributions. Except for the 171 and 193 wavelengths, which are affected by EUV dimming caused by coronal mass ejections (CMEs), we find near-identical size distributions of geometric (lengths L, flare areas A, volumes V, and fractal dimension D{sub 2}), temporal (flare durations T), and spatio-temporal parameters (diffusion coefficient ?, spreading exponent ?, and maximum expansion velocities v{sub max}) in different wavelengths, which are consistent with the universal predictions of the fractal-diffusive avalanche model of a slowly driven, self-organized criticality (FD-SOC) system, i.e., N(L)?L {sup 3}, N(A)?A {sup 2}, N(V)?V {sup 5/3}, N(T)?T {sup 2}, and D{sub 2} = 3/2, for a Euclidean dimension d = 3. Empirically, we find also a new strong correlation ??L {sup 0.940.01} and the three-parameter scaling law L?? T {sup 0.1}, which is more consistent with the logistic-growth model than with classical diffusion. The findings suggest long-range correlation lengths in the FD-SOC system that operate in the vicinity of a critical state, which could be used for predictions of individual extreme events. We find also that eruptive flares (with accompanying CMEs) have larger volumes V, longer flare durations T, higher EUV and soft X-ray fluxes, and somewhat larger diffusion coefficients ? than confined flares (without CMEs)

Aschwanden, Markus J. [Lockheed Martin Advanced Technology Center, Org. ADBS, Bldg. 252, 3251 Hanover St., Palo Alto, CA 94304 (United States); Zhang, Jie; Liu, Kai, E-mail: aschwanden@lmsal.com, E-mail: jzhang7@gmu.edu [School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Dr., MSN 6A2, Fairfax, VA 22030 (United States)

2013-09-20

210

the Law Fund Law Collections Appeal  

E-print Network

Supporting the Law Fund Law Collections Appeal #12;Our Vision The School of Law at the University to come. In launching the Law Collections Appeal, we hope to develop the University of Glasgow law library is committing £5000 to the Law Collections Appeal. Furthermore, individual members of academic staff have

Guo, Zaoyang

211

Charles's Law  

NSDL National Science Digital Library

This interactive presentation, created by Terry Bartelt and hosted by the Electromechanical Digital Library, discusses the history and theory of Charles's Law, which states, "the volume of a given quantity of gas varies directly with its temperature." A series of interactive flash animations show the application of this theory and demonstrate how different heating elements, such as candles and even the Sun, affect the molecules in common things such as balloons and thermometers. Mathematical equations are provided to demonstrate the calculations. Once the presentation is complete, a short quiz is provided to test the full understanding of the Charles's Law.

Bartelt, Terry L.

2009-04-17

212

Newton's Laws  

NSDL National Science Digital Library

The Physics Classroom presents this tutorial on Newton's three laws of motion. The impulse-momentum change theorem and the law of conservation of momentum are introduced, explained and applied to the analysis of collisions of objects. Both exercises provide an activity and then an assessment exercise in order for students to check their understanding of the concept(s). Some of the key topics included here are: mass, motion, force (applied, gravity, normal, friction, air resistance, tensional, and spring), inertia, and terminal velocity. The tutorial is geared toward high school students, but it is also great review material for college physics students or anyone needing a refresher course in vectors.

2007-11-02

213

The Development of Adoption Law.  

ERIC Educational Resources Information Center

Reviews the evolution of U.S. adoption law since 1851. Recounts changes in the perceived "best interests" of all members of the adoption triad over time, and growing recognition of links between adoption and child welfare policy. Discusses current controversies including open adoption, birth parents' rights, unmarried fathers, and the role of

Bussiere, Alice

1998-01-01

214

School Law.  

ERIC Educational Resources Information Center

Summarizes three current issues in school law, including school district suits over potentially carcinogenic asbestos insulation, a California judge's finding that captionless educational television discriminates against hearing-impaired students, and the federal government's attempt to keep the Fairfax (Virginia) school system from charging

Splitt, David A.

1982-01-01

215

Defect interactions with stepped CeO{sub 2}/SrTiO{sub 3} interfaces: Implications for radiation damage evolution and fast ion conduction  

SciTech Connect

Due to reduced dimensions and increased interfacial content, nanocomposite oxides offer improved functionalities in a wide variety of advanced technological applications, including their potential use as radiation tolerant materials. To better understand the role of interface structures in influencing the radiation damage tolerance of oxides, we have conducted atomistic calculations to elucidate the behavior of radiation-induced point defects (vacancies and interstitials) at interface steps in a model CeO{sub 2}/SrTiO{sub 3} system. We find that atomic-scale steps at the interface have substantial influence on the defect behavior, which ultimately dictate the material performance in hostile irradiation environments. Distinctive steps react dissimilarly to cation and anion defects, effectively becoming biased sinks for different types of defects. Steps also attract cation interstitials, leaving behind an excess of immobile vacancies. Further, defects introduce significant structural and chemical distortions primarily at the steps. These two factors are plausible origins for the enhanced amorphization at steps seen in our recent experiments. The present work indicates that comprehensive examination of the interaction of radiation-induced point defects with the atomic-scale topology and defect structure of heterointerfaces is essential to evaluate the radiation tolerance of nanocomposites. Finally, our results have implications for other applications, such as fast ion conduction.

Dholabhai, Pratik P., E-mail: pdholabhai@lanl.gov; Aguiar, Jeffery A.; Uberuaga, Blas P., E-mail: blas@lanl.gov [Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Misra, Amit [Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2014-05-21

216

Defect interactions with stepped CeO2/SrTiO3 interfaces: Implications for radiation damage evolution and fast ion conduction  

NASA Astrophysics Data System (ADS)

Due to reduced dimensions and increased interfacial content, nanocomposite oxides offer improved functionalities in a wide variety of advanced technological applications, including their potential use as radiation tolerant materials. To better understand the role of interface structures in influencing the radiation damage tolerance of oxides, we have conducted atomistic calculations to elucidate the behavior of radiation-induced point defects (vacancies and interstitials) at interface steps in a model CeO2/SrTiO3 system. We find that atomic-scale steps at the interface have substantial influence on the defect behavior, which ultimately dictate the material performance in hostile irradiation environments. Distinctive steps react dissimilarly to cation and anion defects, effectively becoming biased sinks for different types of defects. Steps also attract cation interstitials, leaving behind an excess of immobile vacancies. Further, defects introduce significant structural and chemical distortions primarily at the steps. These two factors are plausible origins for the enhanced amorphization at steps seen in our recent experiments. The present work indicates that comprehensive examination of the interaction of radiation-induced point defects with the atomic-scale topology and defect structure of heterointerfaces is essential to evaluate the radiation tolerance of nanocomposites. Finally, our results have implications for other applications, such as fast ion conduction.

Dholabhai, Pratik P.; Aguiar, Jeffery A.; Misra, Amit; Uberuaga, Blas P.

2014-05-01

217

Effects of damage and viscoelasticity on the constitutive behavior of fiber-reinforced composites  

NASA Astrophysics Data System (ADS)

Linear viscoelastic constitutive relationships incorporating the effects of distributed damage are developed for fiber reinforced composite materials. Micromechanics based analysis is presented to obtain the overall linear viscoelastic response of a matrix cracked cross-ply laminate. A 2-D lower bound solution and an approximate 3-D solution to the overall properties are obtained using the Laplace transform based elastic-viscoelastic correspondence principle. Since the micromechanics-based constitutive equations are specific to the considered laminate geometry and damage modes, they are not suitable for general purpose finite element based structural analysis codes. Further, micromechanics-based constitutive equations may be difficult to obtain when damage is such that no periodic representative volume element can be identified. Thus a more general internal variables based continuum damage model is developed. Using the Laplace transformed based elastic-viscoelastic correspondence principle, a pseudo strain energy function is defined in terms of Laplace transformed strain and damage internal variables. For the case of non-evolving damage, this pseudo strain energy function is expanded as a polynomial in its arguments in accordance with the orthotropic symmetry restriction imposed by the material. The time domain relationships are obtained by inverse Laplace transform. The approach is illustrated for the specific case of matrix cracked symmetric cross-ply laminates. The generality of the approach is illustrated by showing how transient temperature, moisture and physical aging effects can be incorporated. Evolution of damage in viscoelastic laminates is studied using a cohesive finite element approach. A two dimensional, four noded finite element is developed incorporating a rate-independent traction-displacement cohesive law. This element is used in conjunction with plane strain bulk elements behaving in a linear viscoelastic manner to simulate crack evolution between two existing transverse cracks in symmetric cross-ply laminates. The effects of loading strain-rate, ply constraints and initial crack density are studied.

Kumar, Rajesh Shyamraj

218

Undermining Evolution: Where State Standards Go Wrong  

ERIC Educational Resources Information Center

While many states are handling evolution better today than in the past, anti-evolution pressures continue to threaten state science standards. In April 2012, for example, Tennessee passed a law that enables teachers to bring anti-evolution materials into the classroom without being challenged by administrators. This law is similar to the Science

American Educator, 2012

2012-01-01

219

Congenital ureteropelvic junction obstruction: physiopathology, decoupling of tout court pelvic dilatation-obstruction semantic connection, biomarkers to predict renal damage evolution.  

PubMed

The widespread use of fetal ultrasonography results in a frequent antenatally observation of hydronephrosis, ureteropelvic junction obstruction (UPJO) accounting for the greatest fraction of congenital obstructive nephropathy. UPJO may be considered, in most cases, as a functional obstructive condition, depending on defective fetal smooth muscle/nerve development at this level, with lack of peristaltic wave propagation--aperistaltic segment--and, therefore, poor urine ejection from the renal pelvis into the ureter. The UPJO-related physiopathologic events are, at first, the compliant dilatation of renal pelvis that, acting as hydraulic buffer, protects the renal parenchyma from the rising intrapelvic pressure-related potential damages, and, subsequently, beyond such phase of dynamic balance, the tubular cell stretch-stress induced by increased intratubular pressure and following parenchymal inflammatory lesions: inflammatory infiltrates, fibroblast proliferation, activation of myofibroblasts, tubulo-interstitial fibrosis. Reactive oxygen species (ROS), nitric oxide (NO), several chemo- and cytokines, growth factors, prostaglandins and eicosanoids, angiotensin-II are the main pathogenetic mediators of the obstructive nephropathy. Apoptosis of tubular cells is the major cause of the tubular atrophy, together with epithelial-mesenchymal transdifferentiation. Some criticisms on tout court semantic renal pelvis dilatation-obstruction connection have been raised considering that the renal pelvis expansion isn't, in any case, linked to an ostructive condition, as it may be verified by diuretic (furosemide) renogram together with scintiscan-based evaluation of differential renal function. In this regard, rather than repetitive invasive nuclear procedures that expose the children to ionizing radiations, an intriguing noninvasive strategy, based on the evaluation of urinary biomarkers and urinary proteome, can define the UPJO-related possible progress of parenchymal lesions, thus predicting which patients must require an obstruction correcting surgery and in which patients, instead, the hydronephrosis will spontaneously resolve. PMID:22428472

Alberti, C

2012-02-01

220

Gauss' Law (Review) Gauss' law form of  

E-print Network

Gauss' Law (Review) Gauss' law ­ form of Coulomb's law qenc is the total charge enclosed is to A so = 0 Outer endcap = EA #12;Conductors Using Gauss' law and = EA If is charge per unit area If + charge on conductor, E directed away 0 =E #12;Gauss' Law Infinitely long insulating rod with linear

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

221

The laws of emotion  

Microsoft Academic Search

It is argued that emotions are lawful phe- nomena and thus can be described in terms of a set of laws of emotion. These laws result from the operation of emotion mechanisms that are accessible to intentional control to only a limited extent. The law of situational meaning, the law of concern, the law of reality, the laws of change,

Nico H. Frijda

1988-01-01

222

Canterbury Law Scholarships.  

E-print Network

Canterbury Law Scholarships. 2014 School of Law LAW #12;The University of Canterbury School of Law offers scholarships for first year law students. The scholarships are available to students at secondary participation and achievements. Canterbury Law Scholars Five Canterbury Law Scholars will each receive awards

Hickman, Mark

223

Ampere's Law  

NSDL National Science Digital Library

The lesson begins with a demonstration introducing students to the force between two current carrying loops, comparing the attraction and repulsion between the loops to that between two magnets. After formal lecture on Ampere's law, students begin to use the concepts to calculate the magnetic field around a loop. This is applied to determine the magnetic field of a toroid, imagining a toroid as a looped solenoid.

VU Bioengineering RET Program, School of Engineering,

224

Appendix L Patent Laws CONSOLIDATED PATENT LAWS  

E-print Network

Appendix L Patent Laws __________________________________________________________________ CONSOLIDATED PATENT LAWS United States Code Title 35 - Patents Editor's Note (January 2007): The Patent Laws repro duced below supersede those reproduced in the last revision of the Manual of Patent Examining

Luryi, Serge

225

Fractional order viscoelasticity and theoretical progress in rheological constitutive law for rocks  

NASA Astrophysics Data System (ADS)

Fractional calculus has recently become an important tool in the analysis of relaxation phenomena, such as stress-strain relationships in composite materials. This is because the memory effect, an essence of viscoelasticity, cannot be entirely described by the empirical constitutive equations with the integer-order time derivative. We derive a generalized viscoelastic constitutive equation from an energy function with fractional-order time derivatives. The constitutive equation reduces the empirical models of viscoelasticity such as Maxwell, Kelvin-Voigt and Zener models and represents the relaxation behavior of any kind of viscoelastic materials such as polymer, metal and rocks, enabling us to investigate the time-dependent property of relaxation and the origin of power-law dynamics. The constitutive equation is a differential equation with fractional order, and taking the Laplace transformations yield solutions with the Mittag-Leffler function having the asymptotic behavior of temporal power-law. The constitutive equation is hence equivalent to the Boltzmann superposition integral (a definition of the viscoelastic behavior) with power-law kernel, i.e., the Greens function exhibiting temporal power-law relaxation, and in its special case, the kernel becomes an exponential function having a characteristic time. We also analyze experimental data sets on the deformation of rocks such as halite and lherzolite exhibiting the empirical flow-law (the power-law scaling between bulk stress and strain-rate) and show that the behaviors can be described by the viscoelastic constitutive equation with fractional-order derivatives as well. The order of fractional derivative is identical to the reciprocal of stress exponent of flow law reflecting the memory effect in viscoelasticity and the deformation mechanisms of rocks. It is also denoted that the power-law scaling in viscoelastic behavior of rocks is related to aspects of crustal fluid dynamics and change in atmospheric radon concentration associated with damage evolution prior to catastrophic failure (analogous to an earthquake).

Kawada, Y.; Yajima, T.; Nagahama, H.

2010-12-01

226

Analysing the Law of Dynamic Subsidence in Mining Area by Fusing Insar and Leveling Measurements  

NASA Astrophysics Data System (ADS)

Understanding the law of mining surface dynamic subsidence plays an important role in protecting the villages and other infrastructures against subsidence damage and disturbance. Unfortunately, the existed methods are mostly based on a few sparse leveling measurements, the accuracy and reliability of which are degraded when the feature points of the leveling measurements are lost in the processing of subsidence evolution. This paper presents a method to analysing the law of mining surface dynamic subsidence by fusing interferometric synthetic aperture radar (InSAR) and leveling measurements. By comparing the fitted results obtained by fusing InSAR/leveling and those only by independent leveling, it is shown that the InSAR/levelling fusion not only can make up the deficiency when the leveling measurements lost the feature points of dynamic subsidence, but also can improve the accuracy and reliability of results.

Yang, Z. F.; Li, Z. W.; Zhu, J. J.; Hu, J.; Wang, Y. J.; Chen, G. L.

2013-07-01

227

Spatial structure and temporal fluctuations of damage in a discrete element model of geomaterials  

NASA Astrophysics Data System (ADS)

We present a discrete element model of geomaterials and investigate the uniaxial compression of cylindrical specimens. In order to capture the heterogeneous micro-structure of materials the sample is generated by sedimenting randomly sized spherical particles inside a cylindrical container. The cohesive interaction of particles is represented by beam elements which can break when they get overstressed. The breaking rule takes into account the stretching and shear of particle contacts. The time evolution of the system is generated by molecular dynamics simulations. Computer simulations revealed that under strain controlled uniaxial loading of the system first micro-cracks nucleate in an uncorrelated way all over the sample. As loading proceeds localization occurs, i.e. the damage concentrates into a narrow band which has an angle of 30-45 degrees with the load direction. Inside the damage band fragments are obtained with a power law mass distribution embedded into fine powder of single particles. Analyzing the temporal evolution of the breaking process we show that local breaking events form correlated trails which are analogous to acoustic bursts of experiments. Characteristic quantities of bursts such as size (crack surface), energy, and duration, furthermore, the waiting times between consecutive events are characterized by power law distributions over a broad range. We show that the energy and duration of bursts have power law dependence on the crack surface created by bursts. As the system approaches macroscopic failure we pointed out that consecutive bursts get correlated: the average waiting time to the next event proved to be an increasing function of the burst size, furthermore, the formation of the damage band is marked by the decrease of the average distance of consecutive bursts. The simulation results are in reasonable agreement with the experimental findings on sedimentary rocks.

Kun, Ferenc; Varga, Imre; Pl, Gerg?; Lennartz-Sassinek, Sabine; Butler, Ian; Main, Ian

2013-04-01

228

Implementation of a Thermodynamic Framework for Damage Mechanics of Solder Interconnects in Microelectronics Packaging  

Microsoft Academic Search

A thermodynamic framework for damage mechanics is proposed. The damage evolution function uses entropy as a damage metric. A damage-coupled viscoplastic model with kinematic and isotropic hardening is implemented in a commercial finite element code to simulate the thermo-mechanical behavior of eutectic solder interconnectsin micro electronics packaging. The damage, asan internal state variable, is coupled witha unified viscoplastic constitutive model

Cemal Basaran; Hong Tang

2002-01-01

229

CONSTITUTIVE RELATIONSHIP OF TISSUE BEHAVIOR WITH DAMAGE ACCUMULATION OF HUMAN CORTICAL BONE  

PubMed Central

Microdamage accumulation has been identified as a major conduit for bone tissues to absorb fracture energy. Due to the poor understanding of its underlying mechanism, however, an adequate constitutive relationship between damage accumulation and the mechanical behavior of bone has not yet been established. In this study, the constitutive relationship between the damage accumulation induced by overload and the evolution of mechanical properties of bone with incremental deformation was established based on the experimental results obtained from a novel progressive loading protocol developed in our laboratory. First, a decayed exponential model was proposed to capture the damage accumulation (modulus loss) with increasing applied strain. Next, a power law function was proposed to represent the progression of plastic deformation with damage accumulation. Finally, a linear combination of the Kohlrausch-Williams-Watts (KWW) function and Debye function was used to depict the viscoelastic behavior of bone associated with damage accumulation. The results of this study may help develop a constitutive model for predicting the mechanical behavior of cortical bone tissues. PMID:20472239

Luo, Qing; Leng, Huijie; Acuna, Rae; Dong, Xuanliang; Rong, Qiguo; Wang, Xiaodu

2010-01-01

230

Property law in Jersey  

E-print Network

Jersey law, and within it Jersey property law, has received little academic attention. This thesis seeks to examine, and provide a systematic account of, the Jersey law of property. Specific aspects of substantive law ...

MacLeod, Rebecca Frances

2012-06-26

231

State Highway Safety Laws  

MedlinePLUS

State Highway Safety Laws & Funding State Laws Each state and U.S. territory has enacted laws governing various driver behaviors, ... page contains charts for a specific type of highway safety law, listing the provisions for all U.S. ...

232

15 CFR 990.24 - Compliance with other applicable laws and regulations.  

Code of Federal Regulations, 2014 CFR

...Compliance with other applicable laws and regulations. 990.24...POLLUTION ACT REGULATIONS NATURAL RESOURCE DAMAGE ASSESSMENTS...Compliance with other applicable laws and regulations. (a) Worker...for response actions. (b) Natural Resources...

2014-01-01

233

15 CFR 990.24 - Compliance with other applicable laws and regulations.  

Code of Federal Regulations, 2013 CFR

...Compliance with other applicable laws and regulations. 990.24...POLLUTION ACT REGULATIONS NATURAL RESOURCE DAMAGE ASSESSMENTS...Compliance with other applicable laws and regulations. (a) Worker...for response actions. (b) Natural Resources protection....

2013-01-01

234

15 CFR 990.24 - Compliance with other applicable laws and regulations.  

Code of Federal Regulations, 2010 CFR

...Compliance with other applicable laws and regulations. 990.24...POLLUTION ACT REGULATIONS NATURAL RESOURCE DAMAGE ASSESSMENTS...Compliance with other applicable laws and regulations. (a) Worker...for response actions. (b) Natural Resources protection....

2010-01-01

235

43 CFR 11.17 - Compliance with applicable laws and standards.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Compliance with applicable laws and standards. 11.17 Section 11...Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Introduction 11.17 Compliance with applicable laws and standards. (a) Worker health...

2013-10-01

236

43 CFR 11.17 - Compliance with applicable laws and standards.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Compliance with applicable laws and standards. 11.17 Section 11...Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Introduction 11.17 Compliance with applicable laws and standards. (a) Worker health...

2014-10-01

237

15 CFR 990.24 - Compliance with other applicable laws and regulations.  

Code of Federal Regulations, 2012 CFR

...Compliance with other applicable laws and regulations. 990.24...POLLUTION ACT REGULATIONS NATURAL RESOURCE DAMAGE ASSESSMENTS...Compliance with other applicable laws and regulations. (a) Worker...for response actions. (b) Natural Resources protection....

2012-01-01

238

43 CFR 11.17 - Compliance with applicable laws and standards.  

Code of Federal Regulations, 2012 CFR

...2011-10-01 true Compliance with applicable laws and standards. 11.17 Section 11...Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Introduction 11.17 Compliance with applicable laws and standards. (a) Worker health...

2012-10-01

239

43 CFR 11.17 - Compliance with applicable laws and standards.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Compliance with applicable laws and standards. 11.17 Section 11...Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Introduction 11.17 Compliance with applicable laws and standards. (a) Worker health...

2011-10-01

240

15 CFR 990.24 - Compliance with other applicable laws and regulations.  

Code of Federal Regulations, 2011 CFR

...Compliance with other applicable laws and regulations. 990.24...POLLUTION ACT REGULATIONS NATURAL RESOURCE DAMAGE ASSESSMENTS...Compliance with other applicable laws and regulations. (a) Worker...for response actions. (b) Natural Resources protection....

2011-01-01

241

32 CFR 750.48 - Measure of damages in injury or death cases.  

Code of Federal Regulations, 2010 CFR

...or possessions, determine the measure of damages under the law of the location where the injury arises. (b) Where...determined in accordance with general principles of American tort law. The following is provided as guidance. (1)...

2010-07-01

242

The Second Law of Thermodynamics  

NSDL National Science Digital Library

The Second Law of Thermodynamics can be stated as: Energy spontaneously tends to flow from being concentrated in one place to becoming diffused and spread out - or - disorder in a closed system will increase. This radio broadcast explains this law, its implications as to time and energy in the universe, and whether the Second Law tends to be refuted by the existence of life and the theory of evolution. The broadcast explains how the Sun-Earth system is like a steam engine where the Sun is the hot engine, the Earth is a cold sink, and the biosphere plays the part of the pistons by converting energy from the Sun into work needed to provide for life on Earth. There is discussion about the relation between the Second Law and the Big Bang, the expansion of the cosmos, and our inexorable passage through time towards the heat death of the universe; how gravity stores negative energy, which enables it to create order out of disorder; and why the Second Law may be the most fundamental law in all of science. The broadcast is 43 minutes in length.

243

Entropic Corrections to Coulomb's Law  

E-print Network

Two well-known quantum corrections to the area law have been introduced in the literatures, namely, logarithmic and power-law corrections. Logarithmic corrections, arises from loop quantum gravity due to thermal equilibrium fluctuations and quantum fluctuations, while, power-law correction appears in dealing with the entanglement of quantum fields in and out the horizon. Inspired by Verlinde's argument on the entropic force, and assuming the quantum corrected relation for the entropy, we propose the entropic origin for the Coulomb's law in this note. Also we investigate the Uehling potential as a radiative correction to Coulomb potential in 1-loop order and show that for some value of distance the entropic corrections of the Coulomb's law is compatible with the vacuum-polarization correction in QED. So, we derive modified Coulomb's law as well as the entropy corrected Poisson's equation which governing the evolution of the scalar potential $\\phi$. Our study further supports the unification of gravity and electromagnetic interactions based on the holographic principle.

S. H. Hendi; A. Sheykhi

2011-10-17

244

Reassessing Damages in Securities Fraud Class Actions  

Microsoft Academic Search

No coherent doctrinal statement exists for calculating open-market damages for securities fraud class actions. Instead, courts have tried in vain to fashion common-law deceit and misrepresentation remedies to fit open-market fraud. The result is a relatively ineffective system with a hallmark feature: unpredictable damage awards. This poses a significant fraud deterrence problem from both a practical and a theoretical standpoint.

Elizabeth Chamblee Burch

2007-01-01

245

Sexes show differential tolerance to spittlebug damage and consequences of damage for multi-species interactions  

Microsoft Academic Search

Antagonists can play a role in sexual system evolution if tolerance or resistance is sex-dependent. Our understanding of this role will be enhanced by consideration of the effects of antagonists on other plant-animal interactions. This study determined whether the sex morphs of a gynodioecious Fragaria virginiana differ in their susceptibility and response to damage by spittlebugs and whether damage altered

DENISE H. COLE; TIA-LYNN ASHMAN

2005-01-01

246

Continuum damage mechanics for sintered powder metals  

NASA Astrophysics Data System (ADS)

Sintered metals are characterized by the high porosity (? 8%) and voids/micro-cracks in microns. Inelastic behavior of the materials is coupled with micro-crack propagation and coalescence of open voids. In the present work the damage evolution of the sintered iron under multi-axial monotonic loading conditions was investigated experimentally and computationally. The tests indicated that damage of the sintered iron initiated already at a stress level much lower than the macroscopic yield stress. The damage process can be divided into the stress-dominated elastic damage and the plastic damage described by the plastic strain. Based on the uniaxial tensile tests an elastic-plastic continuum damage model was developed which predicts both elastic damage and plastic damage in the sintered iron under general multi-axial monotonic loading conditions. Computational predictions agree with experiments with different multi-axial loading paths. A phenomenological continuum damage model for the sintered metal is developed based on the experimental observations to predict the inelastic behavior and damage process to failure under multi-axial loading conditions. The proposed damage model is experimentally verified under different loading conditions.

Yuan, Huang; Ma, SongYun; Zhang, Long

2015-01-01

247

Damage evolution during creep of steels  

Microsoft Academic Search

Using high-precision constant-stress machines, normal creep curves are recorded over tensile stress ranges giving creep lives up to about 1000h or more for 0.5Cr0.5Mo0.25V ferritic steel, 1Cr1Mo0.25V bainitic steel, 316L austenitic steel and the oxide-dispersion-strengthened 14% Cr ferritic steel, Incoloy MA957. Although the curve shapes are material and test condition sensitive, a minimum rate rather than a secondary or steady-state

B. Wilshire; H. Burt

2008-01-01

248

Plant evolution The Evolution  

E-print Network

Plant evolution The Evolution of Plants by Kathy J. Willis and Jenny C. McElwain. Oxford University Press, 2002. $40.00/£22.99 pbk (378 pages) ISBN 0 19 850065 3 Developmental Genetics and Plant Evolution is observed for treatments of evolution and development. Titles of major monographs on the subject imply

Rieseberg, Loren

249

AALS Law Books Recommended  

Microsoft Academic Search

The years following World War I1 witnessed the creation of many new law schools. Standards were needed for all aspects of both law school and law library administration. The AALS, under the presidency of Professor Walter Gellhorn, sponsored the creation of a major list of titles recommended for acquisitions by academic law libraries. The list, Law Boob Recommended for Libraries,

Mark P. Bernstein

1989-01-01

250

Utah Marriage Divorce Laws  

E-print Network

Utah Marriage & Divorce Laws By Steve Averett J. Reuben Clark Law School Brigham Young University Howard W. Hunter Law Library #12;UTAH MARRIAGE AND DIVORCE LAWS By Steve Averett #12;i UTAH MARRIAGE contains a brief explanation of Utah marriage and divorce laws, as well as sample Utah divorce forms. Some

Seamons, Kent E.

251

Chinese Business Law Postgraduate  

E-print Network

development in China · Principles of Chinese law · Legal institutional framework · Dispute settlement Chinese) · Consumer protection · Due diligence · Product quality legislation · Foreign trade regulations · Entry modes law 4 2 · Customs law & Regulations · Foreign trade law Chinese environmental law 3 2 · Environmental

Einmahl, Uwe

252

Evolution Noonan Evolution 301  

E-print Network

Evolution Noonan Spring 08 Evolution 301 Instructor: Brice Noonan Office: 504 Shoemaker e-mail: bnoonan@olemiss.edu Class time: T,Th: 8:00 ­ 9:15 Office Hrs: T, Th: 9:15 ­ 10:45 Text: Evolution (Futuyma Week 3: Jan 29, 21 Chapter 3: Patterns of Evolution Week 4: Feb 5, 7 Chapter 4,5: Evolution

Goulet, Denis C.

253

What law courses are there? Law and Business  

E-print Network

Essentials What law courses are there? Law Law and Business Law (with a study abroad year) Law with American Studies Law with Business Law with International Relations Law with Politics Graduate Entry LLB other qualifications information, refer to pages 124-127) Typical A level offer range: AAA-AAB For Law

Sussex, University of

254

Kepler's Laws of Planetary Motion  

NSDL National Science Digital Library

This site discusses three of Kepler's laws of planetary motion: the law of ellipses, the equal areas law and the harmonic law. Each law is discussed in detail and includes an interactive animation that is helpful in understanding the law.

2010-04-29

255

Dynamically driven phase transformations in heterogeneous materials. II. Applications including damage  

NASA Astrophysics Data System (ADS)

A model, developed for heterogeneous materials undergoing dynamically driven phase transformations in its constituents, has been extended to include the evolution of damage. Damage is described by two mechanisms: interfacial debonding between the constituents and brittle failure micro-crack growth within the constituents. The analysis is applied to silicon carbide-titanium (SiC-Ti) unidirectional metal matrix composites that undergo the following phenomena: Ti has a yield stress of approximately 0.5 GPa and above a pressure of about 2 GPa undergoes a solid-solid phase transformation. The inelastic work from plastic dissipation contributes to the temperature and pressure rise in the Ti. SiC behaves elastically below a critical stress, above which it is damaged by microcrack growth. Finally, under tensile loading, the interface between Ti and SiC debonds according to an interfacial decohesion law. Each process is first examined independently in order to understand how its characteristic behavior is manifested in the stress-strain response of the composite. The complex interplay between loading states, viscoplasticity, damage, and solid-solid phase transformations is then studied at both the micromechanics and macromechanics levels.

Plohr, JeeYeon N.; Clements, B. E.; Addessio, F. L.

2006-12-01

256

ENVIRONMENTAL LAW NETWORK  

E-print Network

ENVIRONMENTAL LAW NETWORK INTERNATIONAL R?SEAU INTERNATIONAL DE DROIT DE L´ENVIRONNEMENT INTERNATIONALES NETZWERK UMWELTRECHT EU Enforcement Policy of Community Environmental law as presented in the Commission Communication on implementing European Community Environmental law Marta Ballesteros The direct

Paris-Sud XI, Université de

257

The Law School Studies in Law & Criminology  

E-print Network

-depth understanding of crime, justice and punishment in society, fostering a critical approach and drawing such as cyber law, hate crime, medical law, crime and deviance, criminal justice, commercial law, international have thoroughly enjoyed looking into the history of crime and criminality in addition to considering

Diggle, Peter J.

258

A two-scale damage model with material length  

NASA Astrophysics Data System (ADS)

The Note presents the formulation of a class of two-scale damage models involving a micro-structural length. A homogenization method based on asymptotic developments is employed to deduce the macroscopic damage equations. The damage model completely results from energy-based micro-crack propagation laws, without supplementary phenomenological assumptions. We show that the resulting two-scale model has the property of capturing micro-structural lengths. When damage evolves, the micro-structural length is given by the ratio of the surface density of energy dissipated during the micro-crack growth and the macroscopic damage energy release rate per unit volume of the material. The use of fracture criteria based on resistance curves or power laws for sub-critical growth of micro-cracks leads to quasi-brittle and, respectively, time-dependent damage models. To cite this article: C. Dascalu, C. R. Mecanique 337 (2009).

Dascalu, Cristian

2009-09-01

259

Permeability in Damaged Porous Rocks  

NASA Astrophysics Data System (ADS)

A new damage model is proposed to assess permeability changes in deformable cracked porous rocks. It is assumed that cracks do not interact. The damage variable may thus be defined as the spectral decomposition of the second-order crack density tensor. Cracks do not intersect but they are connected to the natural porous network. Therefore, damage increases the intrinsic permeability of the porous medium at the scale of the Representative Elementary Volume (REV). A multi-scale approach is adopted to quantify the influence of anisotropic damage on the intrinsic permeability tensor. The thermodynamic framework encompasses both saturated and unsaturated porous media. In this latter case, three stress state variables are required to fully describe the materials state. Assuming the solid phase to be incompressible makes it possible to resort to two stress state variables only. The stress/strain relationship is derived from Helmholtz free energy. The damage evolution function depends on tensile strains. The intrinsic permeability is split in a natural component and in a damaged component. This latter is first computed by assuming that the flow in cracks is laminar and oriented in the plane of the cracks. In a second stage, the permeability model is improved to account for flow occurring in the direction normal to the crack planes. Computations are presented for saturated rocks. Drained and undrained triaxial compression tests are simulated. Different materials are examined: granite, claystone and sandstone. The results are finally compared with the predictions of the THHMD model previously developed by the first author [1]. The models performance is discussed in the aim of assessing the Excavation Damaged Zone (EDZ).

Arson, C. F.; Pereira, J.

2010-12-01

260

A model of laser-induced damage of KDP based on the coupling of statistics and heat transfer  

NASA Astrophysics Data System (ADS)

By coupling statistics and heat transfer, we investigate numerically laser-induced KDP crystal damage by multi-gigawatt nanosecond pulses. Our model is based on the heating of nanometric absorbing defects that may cooperate when they are sufficiently aggregated. In such a case, they induce locally a strong increase of temperature that may lead to a subsequent damage. Statistics is used to evaluate the initial defect cluster size distribution. When the crystal is illuminated, by considering in addition heat transfer processes, this approach allows to predict damage probabilities and the evolution of the damaged sites density as a function of the laser fluence. We show that the scaling law exponent, linking the critical laser fluence to its pulse duration, takes a value close to 0.3 departing from the standard 0.5 value that is in a good agreement with recents experiments. Furthermore, these results indicate that absorbers involved in KDP damage may be associated with a collection of planar defects.

Duchateau, Guillaume; Dyan, Anthony

2008-01-01

261

Thermomechanics of damage and fatigue by a phase field model  

E-print Network

In the paper we present an isothermal model for describing damage and fatigue by the use of the Ginzburg-Landau (G-L) equation. Fatigue produces progressive damage, which is related with a variation of the internal structure of the material. The G-L equation studies the evolution of the order parameter, which describes the constitutive arrangement of the system and, in this framework, the evolution of damage. The thermodynamic coherence of the model is proved. In the last part of the work, we extend the results of the paper to a non-isothermal system, where fatigue contains thermal effects, which increase the damage of materials.

Giovambattista Amendola; Mauro Fabrizio

2014-10-26

262

A Damage Mechanics-Based Fatigue Life Prediction Model for Solder Joints  

Microsoft Academic Search

A thermomechanical fatigue life prediction model based on the theory of damage mechan- ics is presented. The damage evolution, corresponding to the material degradation under cyclic thermomechanical loading, is quantified thermodynamic framework. The damage, as an internal state variable, is coupled with unified viscoplastic constitutive model to characterize the response of solder alloys. The damage-coupled viscoplastic model with kinematic and

Hong Tang

2008-01-01

263

Evolution towards Symmetry Ferdinand Verhulst and Richard Huveneers  

E-print Network

Evolution towards Symmetry Ferdinand Verhulst and Richard Huveneers Mathematisch Instituut those of today and will the laws of tomorrow still be the same? Henri Poincar´e in `The evolution of the laws', Derni`eres Pens´ees. Abstract The dynamics of time-dependent evolution towards symmetry

Verhulst, Ferdinand

264

Damage analysis and fundamental studies. Quarterly progress report, October-December 1979  

SciTech Connect

Progress on each of the following topics is outlined: (1) rotating target neutron source, (2) fusion materials irradiation test facility, (3) environmental characterization, (4) damage production, and (5) damage microstructure evolution and mechanical behavior. (MOW)

None

1980-02-01

265

Darwinian Evolution and Fractals  

Microsoft Academic Search

Did nature's beauty emerge by chance or was it intelligently designed? Richard Dawkins asserts that evolution is blind aimless chance. Michael Behe believes, on the contrary, that the first cell was intelligently designed. The scientific evidence is that nature's creativity arises from the interplay between chance AND design (laws). Darwin's ``Origin of the Species,'' published 150 years ago in 1859,

Paul H. Carr

2009-01-01

266

Evolution and Friendship  

ERIC Educational Resources Information Center

In 1925, Williams Jennings Bryan, a former congressman from Nebraska and a former Secretary of State under Woodrow Wilson, spent two agonizing weeks defending his religious faith that cost him his life a month after. Bryan was a prosecutor of high school teacher John Scopes, who had violated Tennessee state law by teaching the theory of evolution.

Mena-Werth, Jose

2005-01-01

267

Utah Marriage Divorce Laws  

E-print Network

Utah Marriage & Divorce Laws By Steve Averett J. Reuben Clark Law School Brigham Young University Howard W. Hunter Law Library #12;i UTAH MARRIAGE AND DIVORCE LAWS Steve Averett 2011 Edition #12;ii For Suz and family #12;iii Introduction This manual contains a brief explanation of Utah marriage

Seamons, Kent E.

268

Innovations in Law.  

ERIC Educational Resources Information Center

This issue of "Bill of Rights in Action" looks at historical and recent innovations in law. The first article examines the code of laws developed by the ancient Hebrews which influenced Roman law, English law, and the U.S. Declaration of Independence and Constitution. The second article explores Thomas Jefferson's writing of the Declaration of

Martz, Carlton

2000-01-01

269

Maryland Law and Education.  

ERIC Educational Resources Information Center

This document analyzes the major elements of Maryland school and college law pertaining to governance. While recognizing differences between school and college law in Maryland, this study shows that there are many elements in common between the two. This study will be primarily concerned with civil law rather than criminal law. School personnel or

Dubel, Robert Y.

270

Hyperphysics: Kepler's Laws  

NSDL National Science Digital Library

This Hyperphysics page, from Georgia State University, provides detailed explanations for each of Kepler's Laws: the Law of Orbits, Law of Periods, and the Law of Areas. Each description offers appropriate formulas and equations as well as related images and graphics. Various links are provided throughout the article for related information.

Nave, Carl R.

2008-10-28

271

Tort law and medical malpractice insurance premiums.  

PubMed

This paper estimated the effects of tort law and insurer investment returns on physician malpractice insurance premiums. Data were collected on tort law from 1991 through 2004, and multivariate regression models, including fixed effects for state and year, were used to estimate the effect of changes in tort law on medical malpractice premiums. The premium consequences of national policy changes were simulated. The analysis found that the introduction of a new damage cap lowered malpractice premiums for internal medicine, general surgery, and obstetrics/gynecology by 17.3%, 20.7%, and 25.5%, respectively. Lowering damage caps by dollar 100,000 reduced premiums by 4%. Statutes of repose also resulted in lower premiums. No other tort law changes had the effect of lowering premiums. Simulation results indicate that a national cap of dollar 250,000 on awards for noneconomic damages in all states would imply premium savings of dollar 16.9 billion. Extending a dollar 250,000 cap to all states that do not currently have them would save dollar 1.4 billion annually, or about 8% of the total. A negative effect on malpractice premiums was found for the Dow Jones industrial average, but not for bond prices; effects of the Nasdaq index were not significant for internal medicine, but were marginally significant for surgery and obstetrics premiums. PMID:17176968

Kilgore, Meredith L; Morrisey, Michael A; Nelson, Leonard J

2006-01-01

272

Brittle creep, damage, and time to failure in rocks  

NASA Astrophysics Data System (ADS)

We propose a numerical model based on static fatigue laws in order to model the time-dependent damage and deformation of rocks under creep. An empirical relation between time to failure and applied stress is used to simulate the behavior of each element of our finite element model. We review available data on creep experiments in order to study how the material properties and the loading conditions control the failure time. The main parameter that controls the failure time is the applied stress. Two commonly used models, an exponential tf-exp (-b?/?0) and a power law function tf-?b' fit the data as well. These time-to-failure laws are used at the scale of each element to simulate its damage as a function of its stress history. An element is damaged by decreasing its Young's modulus to simulate the effect of increasing crack density at smaller scales. Elastic interactions between elements and heterogeneity of the mechanical properties lead to the emergence of a complex macroscopic behavior, which is richer than the elementary one. In particular, we observe primary and tertiary creep regimes associated respectively with a power law decay and increase of the rate of strain, damage event and energy release. Our model produces a power law distribution of damage event sizes, with an average size that increases with time as a power law until macroscopic failure. Damage localization emerges at the transition between primary and tertiary creep, when damage rate starts accelerating. The final state of the simulation shows highly damaged bands, similar to shear bands observed in laboratory experiments. The thickness and the orientation of these bands depend on the applied stress. This model thus reproduces many properties of rock creep, which were previously not modeled simultaneously.

Amitrano, David; Helmstetter, AgnS.

2006-11-01

273

Table of Contents Law ....................................................................................................................................................................................................................................... 2  

E-print Network

Table of Contents Law .......................................................................................................................................................................... 36 Law Library Guide ................................................................................................................................................................................................................................... 53 #12;2 Law Law WVU law students have a passion for justice, an interest in how our legal system

Mohaghegh, Shahab

274

Slip instability and state variable friction laws  

Microsoft Academic Search

The dependence of the friction on slip history is described by an experimentally motivated constitutive law where the friction is dependent on slip rate and state variables. The state variables are defined macroscopically by evolution equations for their rates of change in terms of their present values and slip rate. Experiments may strongly suggest that one state variables is adequate

Andy Ruina

1983-01-01

275

Evolution and Conservation H. Bradley Shaffer  

E-print Network

VIII.6 Evolution and Conservation H. Bradley Shaffer OUTLINE 1. Evolution, genetics one of the most pow- erful conservation laws in existence. Landscape Genetics/Genomics. The fields of species and lineages. 1. EVOLUTION, GENETICS, AND CONSERVATION Suppose that you control environmental

Shaffer, H. Bradley

276

Life as a manifestation of the second law of thermodynamics  

Microsoft Academic Search

We examine the thermodynamic evolution of various evolving systems, from primitivephysical systems to complex living systems, and conclude that they involve similar processeswhich are phenomenological manifestations of the second law of thermodynamics. We take thereformulated second law of thermodynamics of Hatsopoulos and Keenan and Kestin and extendit to nonequilibrium regions, where nonequilibrium is described in terms of gradientsmaintaining systems at

Eric D. Schneider; James J. Kay

1994-01-01

277

598 journal of law, medicine & ethics Oversight of Human  

E-print Network

598 journal of law, medicine & ethics Evaluating Oversight of Human Drugs and Medical Devices.g., economic, health, safety, and environmental impacts); (4) and the evolution of an oversight system (i describes nanotechnology in human Jordan Paradise, J.D., is an Associate Professor of Law at Seton Hall

Kokkoli, Efie

278

Adhesive Characterization and Progressive Damage Analysis of Bonded Composite Joints  

NASA Technical Reports Server (NTRS)

The results of an experimental/numerical campaign aimed to develop progressive damage analysis (PDA) tools for predicting the strength of a composite bonded joint under tensile loads are presented. The PDA is based on continuum damage mechanics (CDM) to account for intralaminar damage, and cohesive laws to account for interlaminar and adhesive damage. The adhesive response is characterized using standard fracture specimens and digital image correlation (DIC). The displacement fields measured by DIC are used to calculate the J-integrals, from which the associated cohesive laws of the structural adhesive can be derived. A finite element model of a sandwich conventional splice joint (CSJ) under tensile loads was developed. The simulations indicate that the model is capable of predicting the interactions of damage modes that lead to the failure of the joint.

Girolamo, Donato; Davila, Carlos G.; Leone, Frank A.; Lin, Shih-Yung

2014-01-01

279

Damage accumulation in quasibrittle fracture  

NASA Astrophysics Data System (ADS)

The strength of quasibrittle materials depends on the ensemble of defects inside the sample and on the way damage accumulates before failure. Using large-scale numerical simulations of the random fuse model, we investigate the evolution of the microcrack distribution as the applied load approaches the fracture point. We find that the distribution broadens mostly due to a tendency of cracks to coalesce in a way that increases with system size. We study how the observed behavior depends on the disorder present in the sample and relate the results with fracture size effects.

Manzato, Claudio; Alava, Mikko J.; Zapperi, Stefano

2014-07-01

280

Centre for Business Law & Practice School of Law  

E-print Network

Centre for Business Law & Practice School of Law University of Leeds BUSINESS LAW & PRACTICE REVIEW Law & Practice, 2005 #12;3 1. ABOUT THE CENTRE The Centre for Business Law and Practice is located in the School of Law at the University of Leeds and its aim is to promote the study of all areas of Business Law

Berzins, M.

281

[A Handling Qualities Metric for Damaged Aircraft  

NASA Technical Reports Server (NTRS)

In recent flight tests of F-15 Intelligent Flight Control System (IFCS), software simulated aircraft control surface failures were inserted to evaluate the IFCS adaptive systems. The failure commanded the left stabilator to a fixed position. The adaptive system uses a neural network that is designed to change control law gains, in the event of damage (real or simulated), that allows the aircraft to fly as it had before the damage. The performance of the adaptive system was assessed in terms of its ability to re-establish good onboard model tracking and its ability to decouple roll and pitch response.

Cogan, Bruce; Hayes, Peggy

2009-01-01

282

An Irreversible Thermodynamics Theory for Damage Mechanics of Solids  

Microsoft Academic Search

The entropy production is a non-negative quantity based on irreversible thermodynamics and thus serves as a basis for the systematic description of the irreversible processes occurring in a solid. In this paper, a thermodynamic framework has been presented for damage mechanics of solid materials, where entropy production is used as the sole measure of damage evolution in the system. As

Cemal Basaran; Shihua Nie

2004-01-01

283

A thermodynamics based damage mechanics model for particulate composites  

Microsoft Academic Search

A micro-mechanical damage model is proposed to predict the overall viscoplastic behavior and damage evolution in a particle filled polymer matrix composite. Particulate composite consists of polymer matrix, particle fillers, and an interfacial transition interphase around the filler particles. Yet the composite is treated as a two distinct phase material, namely the matrix and the equivalent particle-interface assembly. The CTE

Cemal Basaran; Shihua Nie

2007-01-01

284

Fundamental Laws of Algebra  

NSDL National Science Digital Library

This learning object from Wisc-Online covers the fundamental laws of algebra. The interactive activity includes slides which cover the following topics: the commutative, associative and distributive laws as applied to addition and multiplication.

Blohowiak, Chad; Jensen, Douglas; Reed, Allen

2005-01-01

285

Newton's 3rd Law  

NSDL National Science Digital Library

This video shows how Newton's Third Law of Motion can be demonstrated using a low-friction "sled" and two rubber bands. The video includes a brief description of Newton's third law and explains the reaction force on the sled.

Fix, Darren

2009-02-26

286

Plate tectonics, damage and inheritance  

NASA Astrophysics Data System (ADS)

The initiation of plate tectonics on Earth is a critical event in our planet's history. The time lag between the first proto-subduction (about 4 billion years ago) and global tectonics (approximately 3 billion years ago) suggests that plates and plate boundaries became widespread over a period of 1 billion years. The reason for this time lag is unknown but fundamental to understanding the origin of plate tectonics. Here we suggest that when sufficient lithospheric damage (which promotes shear localization and long-lived weak zones) combines with transient mantle flow and migrating proto-subduction, it leads to the accumulation of weak plate boundaries and eventually to fully formed tectonic plates driven by subduction alone. We simulate this process using a grain evolution and damage mechanism with a composite rheology (which is compatible with field and laboratory observations of polycrystalline rocks), coupled to an idealized model of pressure-driven lithospheric flow in which a low-pressure zone is equivalent to the suction of convective downwellings. In the simplest case, for Earth-like conditions, a few successive rotations of the driving pressure field yield relic damaged weak zones that are inherited by the lithospheric flow to form a nearly perfect plate, with passive spreading and strike-slip margins that persist and localize further, even though flow is driven only by subduction. But for hotter surface conditions, such as those on Venus, accumulation and inheritance of damage is negligible; hence only subduction zones survive and plate tectonics does not spread, which corresponds to observations. After plates have developed, continued changes in driving forces, combined with inherited damage and weak zones, promote increased tectonic complexity, such as oblique subduction, strike-slip boundaries that are subparallel to plate motion, and spalling of minor plates.

Bercovici, David; Ricard, Yanick

2014-04-01

287

Plate tectonics, damage and inheritance.  

PubMed

The initiation of plate tectonics on Earth is a critical event in our planet's history. The time lag between the first proto-subduction (about 4?billion years ago) and global tectonics (approximately 3?billion years ago) suggests that plates and plate boundaries became widespread over a period of 1?billion years. The reason for this time lag is unknown but fundamental to understanding the origin of plate tectonics. Here we suggest that when sufficient lithospheric damage (which promotes shear localization and long-lived weak zones) combines with transient mantle flow and migrating proto-subduction, it leads to the accumulation of weak plate boundaries and eventually to fully formed tectonic plates driven by subduction alone. We simulate this process using a grain evolution and damage mechanism with a composite rheology (which is compatible with field and laboratory observations of polycrystalline rocks), coupled to an idealized model of pressure-driven lithospheric flow in which a low-pressure zone is equivalent to the suction of convective downwellings. In the simplest case, for Earth-like conditions, a few successive rotations of the driving pressure field yield relic damaged weak zones that are inherited by the lithospheric flow to form a nearly perfect plate, with passive spreading and strike-slip margins that persist and localize further, even though flow is driven only by subduction. But for hotter surface conditions, such as those on Venus, accumulation and inheritance of damage is negligible; hence only subduction zones survive and plate tectonics does not spread, which corresponds to observations. After plates have developed, continued changes in driving forces, combined with inherited damage and weak zones, promote increased tectonic complexity, such as oblique subduction, strike-slip boundaries that are subparallel to plate motion, and spalling of minor plates. PMID:24717430

Bercovici, David; Ricard, Yanick

2014-04-24

288

Generalized law for aftershocks  

NSDL National Science Digital Library

A generalized law for aftershock decay rates is provided through the combination of the Gutenberg-Richter frequency magnitude relation, Bath's law, and the modified Omori's law. Several large quakes with readily identified aftershocks were studied. Results indicate that aftershock decay rates depended on several parameters specific to each seismic region. It was found that the law can be used to forecast the rate of aftershock occurrence after specific information about the main shock's magnitude and the area's land is known.

Robert Shcherbakov

289

Advertising Law Internet Site  

NSDL National Science Digital Library

The Advertising Law Internet Site houses articles about the legal aspects of marketing products, with particular emphasis on infomercials, home shopping, and direct response TV. Other articles discuss 900 Number regulations, contest laws, business opportunity laws, and additional aspects of promotion law. The site also houses copies of FTC Guides and Speeches and FTC Rules and statutes. Consumer Advisories issued by the FTC will also be made available at the site.

290

Law of Large Numbers  

NSDL National Science Digital Library

Created by Charles M. Grinstead and J. Laurie Snell of Dartmouth College, this website is part of an online statistics textbook. Topics include: (1) Law of Large Numbers for Discrete Random Variables, (2) Chebyshev Inequality, (3) Law of Averages, (4) Law of Large Numbers for Continuous Random Variables, (5) Monte Carlo Method. There are several examples and exercises that accompany the material.

Grinstead, Charles M.

291

Newton's Laws of Motion  

Microsoft Academic Search

THERE is a point in connection with Newton's laws of motion which tha text-books on dynamics, which found the science upon those laws, seem to me to leave very inconveniently and unnecessarily mysterious. The point to which I allude is the meaning of the words ``rest or uniform motion in a straight line'' in the first law. The difficult words

1887-01-01

292

On Teaching Natural Law.  

ERIC Educational Resources Information Center

A brief look at Columbia, Harvard, and Notre Dame law schools shows that the American tradition in teaching natural law has not been strong. The value of teaching natural law is discussed, a separate course or seminar is seen as the most effective option, and a selection of available sources for such a course is appended. (JMD)

Forte, David F.

1978-01-01

293

SECOND LAW OF THERMODYNAMICS  

E-print Network

SECOND LAW OF THERMODYNAMICS: STATUS AND CHALLENGES San Diego, California, USA 14 ­ 15 June 2011 The First Law of energy conservation was even known (Joule 1843) and long before Thermodynamic concepts were, including this one. The Laws of Thermodynamics have much wider, including philosophical significance

Kostic, Milivoje M.

294

Laws of Thermodynamics  

NSDL National Science Digital Library

This lesson explains the two laws of thermodynamics that govern the relationship between energy and natural systems. These are the Law of Conservation of Energy and Law of Entropy. Key terms are hyperlinked so that students can easily find definitions to unfamiliar words.

2012-06-11

295

Bicycle Law Enforcement Manual.  

ERIC Educational Resources Information Center

This manual is an attempt to draw together relevant resources and information for localities interested in developing a bicycle law enforcement operation. It is divided into five major sections. Section I explains the need for and importance of bicycle law enforcement. In section II are presented examples of past and current bicycle law

Hunter, William W.; Stutts, Jane C.

296

Kepler and his Laws  

NSDL National Science Digital Library

This lesson discusses the work of Tycho Brahe and his connection with Johannes Kepler. Students will receive an introduction to conic sections along with Kepler's laws and observe the mathematical formulation of the third law, and its explicit form for artificial Earth satellites. In addition, the student will confirm Kepler's third law by comparing orbital periods and mean distances for all major planets.

Stern, David

297

The Laws Are Yours.  

ERIC Educational Resources Information Center

The pamphlet briefly describes various facets of the law and legal system in Wisconsin, and defines many legal terms. The objective is to further public understanding of the law and of the legal profession, particularly in Wisconsin. No attempt is made to answer specific legal questions. Sections cover civil and criminal law; the federal court

Lawyers' Wives of Wisconsin, Racine.

298

The Law School Announcements  

E-print Network

#12;The Law School Announcements Fall 2011 #12;The University of Chicago 3 Table of Contents 7 Officers and Faculty 7 Officers of Administration 7 Officers of Instruction 10 Lecturers in Law 11 Teaching expiring in 2013­2014 15 The Law School 15 History 16 Educational Mission 17 Programs of Instruction 17

Butler, Laurie J.

299

Campus Common Law  

ERIC Educational Resources Information Center

Discusses the legal principle of common law as it applies to the personnel policies of colleges and universities in an attempt to define the parameters of campus common law and to clarify its relationship to written university policies and relevant state laws. (JG)

Bakken, Gordon Morris

1976-01-01

300

Law of Empires.  

ERIC Educational Resources Information Center

This issue of "Bill of Rights in Action" explores issues raised by empires and imperial law. The first article, "Clash of Empires: The Fight for North America," looks at the clash of empires and the fight for North America during the 18th century. The second article, "When Roman Law Ruled the Western World," examines Roman Law, which helped hold

Martz, Carlton

2001-01-01

301

Natural Resource and Environmental Law and Policy Minor (Code No. 670): 2010-11 Name: Last Update: Checksheet updated  

E-print Network

Natural Resource and Environmental Law and Policy Minor (Code No. 670): 2010-11 Name: Last Update) Evolution of U.S. Environmental and Nat. Res. Law AREC 253 (4) Environmental Law AREC 432 (4) Natural Resource Policy and Law FOR 462 (3) Select 16 credits from the list below Agricultural and Food Policy

Tullos, Desiree

302

Validity of Thermodynamical Laws in Dark Energy Filled Universe  

E-print Network

We have considered the flat FRW model of the universe which is filled with only dark energy. The general descriptions of first and second laws of thermodynamics are investigated on the apparent horizon and event horizon of the universe. We have assumed the equation of state of three different types of dark energy models. We have examined the validity of first and second laws of thermodynamics on apparent and event horizons for these dark energies. For these dark energy models, it has been found that on the apparent horizon, first and second laws are always valid. On the event horizon, the laws are break down for dark energy models 1 and 2. For model 3, first law cannot be satisfied on the event horizon, but second law may be satisfied at the late stage of the evolution of the universe and so the validity of second law on the event horizon depends on the values of the parameters only.

Samarpita Bhattacharya; Ujjal Debnath

2010-12-26

303

Is Life Law-Like?  

PubMed Central

Genes are generally assumed to be primary biological causes of biological phenotypes and their evolution. In just over a century, a research agenda that has built on Mendels experiments and on Darwins theory of natural selection as a law of nature has had unprecedented scientific success in isolating and characterizing many aspects of genetic causation. We revel in these successes, and yet the story is not quite so simple. The complex cooperative nature of genetic architecture and its evolution include teasingly tractable components, but much remains elusive. The proliferation of data generated in our omics age raises the question of whether we even have (or need) a unified theory or law of life, or even clear standards of inference by which to answer the question. If not, this not only has implications for the widely promulgated belief that we will soon be able to predict phenotypes like disease risk from genes, but also speaks to the limitations in the underlying science itself. Much of life seems to be characterized by ad hoc, ephemeral, contextual probabilism without proper underlying distributions. To the extent that this is true, causal effects are not asymptotically predictable, and new ways of understanding life may be required. PMID:21828277

Weiss, Kenneth M.; Buchanan, Anne V.

2011-01-01

304

Faculty of Law Faculty of Law  

E-print Network

Commercial Papers & Banking Transactions 0410333 04102143Real Rights0410317 04103143Private International LawHealth Promotion of Individuals and the Community 9910101 -------3Principles of First Aid9910105 -------3

305

Composite blade damaging under impact  

NASA Astrophysics Data System (ADS)

Composites materials are now being used in primary aircraft structures, and other domains because of numerous advantages. A part of a continuous in-flight operating costs, gas turbine engine manufacturers are always looking for ways to decrease engine weight. This is the case of compressor blades which have to satisfy, for example, the standard bird strike or debris in order to measure the crashworthiness. Bird strike impacts are actually among the most challenging loads that composite blades must accommodate. Thus for the further development of composite structures, it becomes important to have available predictive tools for simulating the response of composite structures under crash or impact loads, which will allow to evaluate damage state in the structure in function of time. A composites damage model, without mesh dependency, is presented, and allows to obtain agreement with impact experiment. Examples of finite element simulations for the impact response of blade based on this materials model are developped. These numerical results correspond to a bird strike on an equivalent composites blade, and insists on damage evolution in structure.

Menouillard, T.; Rthor, J.; Bung, H.; Suffis, A.

2006-08-01

306

The Law of Hazardous Waste: CERCLA, RCRA, & Common Law Claims  

E-print Network

Law 273.4 The Law of Hazardous Waste: CERCLA, RCRA, & Common Law Claims (Fall 2008) Units: 3 CCN (2, The Law of Hazardous Waste Disposal and Remediation (2d ed. 2005) Syllabus Class 1 ­ August 19 Claims on Federal Law: 1. Miller & Johnston The Law of Hazardous Waste Disposal and Remediation 2. Ch. III, Intro

Kammen, Daniel M.

307

law.wlu.edu 121School of Law  

E-print Network

120 X The School of law law.wlu.edu #12;121School of Law The School of law Kenneth Patrick Ruscio President of the University To Be Named Provost Rodney A. Smolla, J.D. Dean of the School of Law Blake Dominic Morant, J.D. Associate Dean for Academic Affairs of the School of Law Sidney S. Evans, J

Dresden, Gregory

308

Subsurface damage on ground fused silica surfaces  

NASA Astrophysics Data System (ADS)

The low surface laser damage threshold of fused silica components in high power laser systems such as NIF restricts the improvement of the output fluence of those systems. Once damage is initiated and grows under subsequent laser shots, the components will go unusable. Subsurface damage (SSD) introduced during manufacturing has been identified as a main damage initiator. A good knowledge of SSD and how manufacturing influences it is essential to optimize manufacturing processes for damage free optics. Using the magneto-rheological finishing (MRF) wedge technique of better accuracy attributed to a tip, we have characterized the subsurface damage on fused silica optical surfaces ground with loose Al2O3 abrasives of different sizes. Larger abrasives generates longer cracks and the number density of cracks decreases sharply with the depth for each size. Rogue particles account for the occurrence of trailing indent scratches. Addition of rogue abrasives into relatively small base abrasive extends SSD more deeply than that induced by rogue abrasives alone. The linear model, with the proportional coefficient 3.511, fits the relationship between SSD depth and surface roughness (SR) better than the quadratic polynomial one. We believe SSD depth relates to SR more statistically than following some specified physical law. The linear relationship between SSD depth and the abrasive size was also established. The abrasive size turned out not to be as a good indictor of SSD depth as SR.

Xu, Jiafeng; Xu, Xueke; Gao, Wenlan; Wei, Chaoyang; Yang, Minghong; Shao, Jianda

2014-08-01

309

Quantum Mechanics reconstruction from invariance of the laws of nature under tensor composition  

E-print Network

Quantum and classical mechanics are derived using four natural physical principles: (1) the laws of nature are invariant under time evolution, (2) the laws of nature are invariant under tensor composition, (3) the laws of nature are relational, and (4) positivity (the ability to define a physical state). Quantum mechanics is singled out by a fifth experimentally justified postulate: nature violates Bell's inequalities.

Florin Moldoveanu

2014-07-29

310

AN EXACTLY CONSERVATIVE PARTICLE METHOD FOR ONE DIMENSIONAL SCALAR CONSERVATION LAWS  

E-print Network

AN EXACTLY CONSERVATIVE PARTICLE METHOD FOR ONE DIMENSIONAL SCALAR CONSERVATION LAWS YOSSI FARJOUN Cambridge MA 02139, USA Abstract. A particle scheme for scalar conservation laws in one space dimension resolutions. 1. Introduction Conservation laws are important models for the evolution of continuum quantities

311

The Riemann problem for a class of resonant hyperbolic systems of balance laws  

E-print Network

of balance laws, which is motivated by the Euler system of compressible fluids in a nozzle with variable the evolution of a fluid flow in a nozzle with discontinuous cross-section. R´esum´e. Nous r´esolvons le probl conservation law, entropy solution, resonant, shock wave, balance law, Riemann problem, nozzle, fluid flow. 1

312

Helmholtz solitons in power-law optical materials  

SciTech Connect

A nonlinear Helmholtz equation for optical materials with regimes of power-law type of nonlinearity is proposed. This model captures the evolution of broad beams at any angle with respect to the reference direction in a wide range of media, including some semiconductors, doped glasses, and liquid crystals. Exact analytical soliton solutions are presented for a generic nonlinearity, within which known Kerr solitons comprise a subset. Three general conservation laws are also reported. Analysis and numerical simulations examine the stability of the Helmholtz power-law solitons. A propagation feature, associated with spatial solitons in power-law media, constituting a class of oscillatory solution, is identified.

Christian, J. M.; McDonald, G. S.; Potton, R. J.; Chamorro-Posada, P. [Joule Physics Laboratory, School of Computing, Science and Engineering, Institute for Materials Research, University of Salford, Salford M5 4WT (United Kingdom); Departamento de Teoria de la Senal y Comunicaciones e Ingenieria Telematica, Universidad de Valladolid, ETSI Telecomunicacion, Campus Miguel Delibes s/n, 47011 Valladolid (Spain)

2007-09-15

313

Conservation law of operator current in open quantum systems  

E-print Network

We derive a fundamental conservation law of operator current for master equations describing reduced quantum systems. If this law is broken, the temporal integral of the current operator of an arbitrary system observable does not yield in general the change of that observable in the evolution. We study Lindblad-type master equations as examples and prove that the application of the secular approximation during their derivation results in a violation of the conservation law. We show that generally any violation of the law leads to artificial corrections to the complete quantum dynamics, thus questioning the accuracy of the particular master equation.

J. Salmilehto; P. Solinas; M. Mttnen

2011-10-25

314

Numerical Modeling of Fatigue Damage and Fissure Propagation under Cyclic Loadings  

Microsoft Academic Search

The purpose of this work is to develop a numerical simulation procedure in order to predict the evolution of the fatigue damage and rupture in mechanical parts (such as rolling bearings and gears) under cyclic loadings. The study of the fatigue damage evolution, from the first defect appearance until the part's failure, is primordial in view of the preventive maintenance.

F. Bogard; P. Lestriez; Y. Q. Guo

2008-01-01

315

CHARACTERIZATION OF DAMAGED MATERIALS  

SciTech Connect

Thermal damage experiments were conducted on LX-04, LX-10, and LX-17 at high temperatures. Both pristine and damaged samples were characterized for their material properties. A pycnometer was used to determine sample true density and porosity. Gas permeability was measured in a newly procured system (diffusion permeameter). Burn rate was measured in the LLNL strand burner. Weight losses upon thermal exposure were insignificant. Damaged pressed parts expanded, resulting in a reduction of bulk density by up to 10%. Both gas permeabilities and burn rates of the damaged samples increased by several orders of magnitude due to higher porosity and lower density. Moduli of the damaged materials decreased significantly, an indication that the materials became weaker mechanically. Damaged materials were more sensitive to shock initiation at high temperatures. No significant sensitization was observed when the damaged samples were tested at room temperature.

Hsu, P C; Dehaven, M; McClelland, M; Chidester, S; Maienschein, J L

2006-06-23

316

[Sources of law].  

PubMed

In it first article, the Civil Code establishes that the sources of Spanish law are law, custom, and the general principles of law as well as the circumstances in which each one of them is applied. The Spanish Constitution (SC) is the Law of Laws. It gathers the fundamental rights of the person who should respect the guidelines of the lower ranking. The Law is the guideline having the maximum category below the SC, its elaboration corresponds to the General Courts although the executive power may legislate in certain circumstances (by delegation of the legislative power or by emergency). Executive power elaborates Regulations that are technical developments of the laws. The regulations of the Regional Communities have the rank of law in their geographic setting and for the material in which it has competence. The validly agreed upon international treaties form a part of the Spanish set of rules after being published in the Official State Bulletin. The Spanish legal system is hierarchical, the rules coming from community law are within the peak of the pyramidal structure, with preference on the constitution, followed by laws and rules. PMID:15719282

Gutierrez Luna, M

2004-12-01

317

Undergraduate Handbook School of Law  

E-print Network

Undergraduate Handbook School of Law Critique. LLB 2013LAW #12;Contents 1 From the Dean Welcome to the School of Law 3 Law degrees at UC 4 Double degrees at UC 5 Planning your degree 6 Specialisations & career opportunities 9 Law School staff 11 2013 course supervisors 12 Law facilities 14 Academic

Hickman, Mark

318

High-density polyethylene damage at extreme tensile conditions  

NASA Astrophysics Data System (ADS)

In-situ and postmortem observations of the dynamic tensile failure and damage evolution of high-density polyethylene (HDPE) are made during Dynamic-Tensile-Extrusion (Dyn-Ten-Ext) loading. The Dyn-Ten-Ext technique probes the tensile response of materials at large strains (>1) and high strain-rates (>105 s-1) by firing projectiles through a conical die. Postmortem sectioning elucidates a mechanism of internal damage inception and progression. X-ray computed tomography corroborates shear damage with cracks nearly aligned with the extrusion axis but separated by unfailed internal bridges of material. In-situ measurements of damage are made with the impact system for ultrafast synchrotron experiments (IMPULSE) using the advanced imaging X-ray methods available at the Advanced Photon Source. Multiple frame phase-contrast imaging (PCI) elucidates the evolution of damage features in HDPE during Dyn-Ten-Ext loading that is observed in postmortem sectioning and X-ray tomography.

Brown, E. N.; Furmanski, J.; Ramos, K. J.; Dattelbaum, D. M.; Jensen, B. J.; Iverson, A. J.; Carlson, C. A.; Fezzaa, K.; Gray, G. T., III; Patterson, B. M.; Trujillo, C. P.; Martinez, D. T.; Pierce, T. H.

2014-05-01

319

Damage control resuscitation: history, theory and technique  

PubMed Central

Damage control resuscitation (DCR) represents the natural evolution of the initial concept of damage control surgery. It currently includes early blood product transfusion, immediate arrest and/or temporization of ongoing hemorrhage (i.e., temporary intravascular shunts and/or balloon tamponade) as well as restoration of blood volume and physiologic/hematologic stability. As a result, DCR addresses the early coagulopathy of trauma, avoids massive crystalloid resuscitation and leaves the peritoneal cavity open when a patient approaches physiologic exhaustion without improvement. This concept also applies to severe injuries within anatomical transition zones as well as extremities. This review will discuss each of these concepts in detail. PMID:24461267

Ball, Chad G.

2014-01-01

320

Acid mine drainage: Common law, SMCRA, and the Clean Water Act  

SciTech Connect

Acid mine drainage is a major problem related to coal mining which, if unabated, can severely damage the aquatic environment. Damage resulting from acid mine drainage was first addressed by common law and riparian principles. As societal laws changed, common law principles alone could not effectively control this problem. Preventing and controlling pollution including acid mine drainage are important goals of the Surface Mining Control Reclamation Act (SMCRA) and the Clean Water Act (CWA). This article examines how common law, SMCRA, and the CWA address the acid mine drainage issue independently, and how improvements in the control of acid mine drainage can be achieved.

Henrich, C.

1995-12-31

321

The evolution of airplanes  

NASA Astrophysics Data System (ADS)

The prevailing view is that we cannot witness biological evolution because it occurred on a time scale immensely greater than our lifetime. Here, we show that we can witness evolution in our lifetime by watching the evolution of the flying human-and-machine species: the airplane. We document this evolution, and we also predict it based on a physics principle: the constructal law. We show that the airplanes must obey theoretical allometric rules that unite them with the birds and other animals. For example, the larger airplanes are faster, more efficient as vehicles, and have greater range. The engine mass is proportional to the body size: this scaling is analogous to animal design, where the mass of the motive organs (muscle, heart, lung) is proportional to the body size. Large or small, airplanes exhibit a proportionality between wing span and fuselage length, and between fuel load and body size. The animal-design counterparts of these features are evident. The view that emerges is that the evolution phenomenon is broader than biological evolution. The evolution of technology, river basins, and animal design is one phenomenon, and it belongs in physics.

Bejan, A.; Charles, J. D.; Lorente, S.

2014-07-01

322

A damage model for ductile crack initiation and propagation  

Microsoft Academic Search

Damage-induced ductile crack initiation and propagation is modeled using a constitutive law with asymmetrical contraction\\u000a of the yield surface and tip remeshing combined with a nonlocal strain technique. In practice, this means that the void fraction\\u000a depends on a nonlocal strain. Finite strain plasticity is used with smoothing of the complementarity condition. The prototype\\u000a constitutive laws take into account pressure

P. Areias; N. Van Goethem; E. B. Pires

2011-01-01

323

Stochastic modeling of p53-regulated apoptosis upon radiation damage  

E-print Network

We develop and study the evolution of a model of radiation induced apoptosis in cells using stochastic simulations, and identified key protein targets for effective mitigation of radiation damage. We identified several key proteins associated with cellular apoptosis using an extensive literature survey. In particular, we focus on the p53 transcription dependent and p53 transcription independent pathways for mitochondrial apoptosis. Our model reproduces known p53 oscillations following radiation damage. The key, experimentally testable hypotheses that we generate are - inhibition of PUMA is an effective strategy for mitigation of radiation damage if the treatment is administered immediately, at later stages following radiation damage, inhibition of tBid is more effective.

Bhatt, Divesh; Bahar, Ivet

2011-01-01

324

Damage monitoring of refractory wall in a generic entrained-bed slagging gasification system  

E-print Network

791 Damage monitoring of refractory wall in a generic entrained-bed slagging gasification system-bed slagging gasification systems is attributed to evolution of structural damage in the refractory walls. Early detection of such damage is necessary to avert unscheduled shutdown of a gasification plant

Ray, Asok

325

On Hack's Law  

NASA Astrophysics Data System (ADS)

Hack's law is reviewed, emphasizing its implications for the elongation of river basins as well as its connections with their fractal characteristics. The relation between Hack's law and the internal structure of river basins is investigated experimentally through digital elevation models. It is found that Hack's exponent, elongation, and some relevant fractal characters are closely related. The self-affine character of basin boundaries is shown to be connected to the power law decay of the probability of total contributing areas at any link and to Hack's law. An explanation for Hack's law is derived from scaling arguments. From the results we suggest that a statistical framework referring to the scaling invariance of the entire basin structure should be used in the interpretation of Hack's law.

Rigon, Riccardo; Rodriguez-Iturbe, Ignacio; Maritan, Amos; Giacometti, Achille; Tarboton, David G.; Rinaldo, Andrea

1996-11-01

326

Statistical laws in linguistics  

E-print Network

Zipf's law is just one out of many universal laws proposed to describe statistical regularities in language. Here we review and critically discuss how these laws can be statistically interpreted, fitted, and tested (falsified). The modern availability of large databases of written text allows for tests with an unprecedent statistical accuracy and also a characterization of the fluctuations around the typical behavior. We find that fluctuations are usually much larger than expected based on simplifying statistical assumptions (e.g., independence and lack of correlations between observations).These simplifications appear also in usual statistical tests so that the large fluctuations can be erroneously interpreted as a falsification of the law. Instead, here we argue that linguistic laws are only meaningful (falsifiable) if accompanied by a model for which the fluctuations can be computed (e.g., a generative model of the text). The large fluctuations we report show that the constraints imposed by linguistic laws...

Altmann, Eduardo G

2015-01-01

327

Darwinian Evolution and Fractals  

NASA Astrophysics Data System (ADS)

Did nature's beauty emerge by chance or was it intelligently designed? Richard Dawkins asserts that evolution is blind aimless chance. Michael Behe believes, on the contrary, that the first cell was intelligently designed. The scientific evidence is that nature's creativity arises from the interplay between chance AND design (laws). Darwin's ``Origin of the Species,'' published 150 years ago in 1859, characterized evolution as the interplay between variations (symbolized by dice) and the natural selection law (design). This is evident in recent discoveries in DNA, Madelbrot's Fractal Geometry of Nature, and the success of the genetic design algorithm. Algorithms for generating fractals have the same interplay between randomness and law as evolution. Fractal statistics, which are not completely random, characterize such phenomena such as fluctuations in the stock market, the Nile River, rainfall, and tree rings. As chaos theorist Joseph Ford put it: God plays dice, but the dice are loaded. Thus Darwin, in discovering the evolutionary interplay between variations and natural selection, was throwing God's dice!

Carr, Paul H.

2009-05-01

328

Newton's Second Law  

NSDL National Science Digital Library

This lesson introduces students to Sir Isaac Newton's Second Law of Motion. Topics include the two ways to study the dynamics of a system in which there is motion, a brief description of Newton's work in studying and measuring the motion of objects, and a summary of his three laws of motion. The lesson includes an activity in which students test Newton's Second Law by measuring the acceleration of a cart which is being pulled by increasingly larger masses.

Pratte, John

329

Law and Finance  

Microsoft Academic Search

This paper examines legal rules covering protection of corporate shareholders and creditors, the origin of these rules, and the quality of their enforcement in 49 countries. The results show that commonlaw countries generally have the strongest, and french civil law countries the weakest, legal protections of investors, with German-and Scandinavian-civillaw countries located in the middle. We also find that concentration

Rafael La Porta; Florencio Lopez-de-Silanes; Andrei Shleifer; Robert W. Vishny

1998-01-01

330

Sexes show differential tolerance to spittlebug damage and consequences of damage for multi-species interactions.  

PubMed

Antagonists can play a role in sexual system evolution if tolerance or resistance is sex-dependent. Our understanding of this role will be enhanced by consideration of the effects of antagonists on other plant-animal interactions. This study determined whether the sex morphs of a gynodioecious Fragaria virginiana differ in their susceptibility and response to damage by spittlebugs and whether damage altered pollinator attraction traits or interactions with other antagonists. Tolerance, but not resistance, to spittlebugs differed between the sexes. Generally, spittlebugs were more damaging to hermaphrodites than females, a finding in accord with the hypothesis that the pollen-bearing morph is less tolerant of source-damage than the pollen-sterile morph when damage is incurred during flowering. In both sex morphs, spittlebugs reduced inflorescence height, increased petal size, but did not affect the number of open flowers per day, suggesting that the net effect of damage may be to increase pollinator attraction. Spittlebug infestation modified interactions with other antagonists in a sex-dependent manner: spittlebugs reduced attack by bud-clipping weevils in hermaphrodites but increased infection by leaf fungi in females. The complex interactions between plant sex, antagonists, and pollinator attraction documented here emphasize the importance of considering sex-differential multi-species interactions in plant sexual evolution. PMID:21646088

Cole, Denise H; Ashman, Tia-Lynn

2005-10-01

331

Zipf's law, power laws and maximum entropy  

NASA Astrophysics Data System (ADS)

Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplinesfrom astronomy to demographics to software structure to economics to linguistics to zoology, and even warfare. A recent model of random group formation (RGF) attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present paper I argue that the specific cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified.

Visser, Matt

2013-04-01

332

Law.com  

NSDL National Science Digital Library

Describing itself as "a single, comprehensive destination for legal information, e-law services and legal products on the Web," this Website offers law students, legal professionals, business firms, and the general public news and information on the law. Lawyers will find here such items as the complete text of the latest edition of the American Lawyer with its listing of the top 100 law firms in the country. Law students can take advantage of features about schools, transferring, and recruiting, as well as links to professional associations. Businesses can find news and analysis of recent issues in business law as well as updated, annotated links to business law sites. For the public, the site offers news and analysis on prominent legal issues, such as recent Supreme Court decisions and the Wisconsin suit against the EPA over formulated gasoline. In addition, an online Real Life Dictionary of the Law gives accessible definitions to over 3,000 common legal terms. The search engine for the site draws on a surprisingly extensive archive -- for instance, we received more than 350 returns for "bankruptcy" -- making this site also a manageable resource for legal research, especially for practicing lawyers, journalists, and the general public. While this is a commercial site offering to sell law books, pamphlets, multimedia materials, and various online services, there is a considerable collection of free materials for users.

333

European Environmental Law Homepage  

NSDL National Science Digital Library

The European Environmental Law Homepage provides access to the full text of treaties, legislation, case law, scholarly legal articles, and EU and NGO documents relevant to environmental law in Europe. In addition, the site has compiled a directory of important governmental Websites for most nations in Europe and maintains a list of pointers to other legal sites with environmental information. The site is edited by Wybe Th. Douma of the T.M.C. Asser Institute, and Jurgen G.J. Lefevere of both the Foundation for International Environmental Law and Development, and the METRO Institute, Maastricht University.

334

Bullying Policies and Laws  

MedlinePLUS

... Policies & Laws | Espaol Search Stopbullying.gov WHAT IS BULLYING Definition The Roles Kids Play Related Topics CYBER BULLYING What is Cyberbullying? Prevent Cyberbullying Report Cyberbullying WHO ...

335

German Law Archive  

NSDL National Science Digital Library

Maintained by Gerhard Dannemann of the Centre for the Advanced Study of European and Comparative Law at University of Oxford, this site features cases, literature, and bibliographies on German law. Documents contained in the archive are organized in four sections: Judgments and other decisions by German courts; Statues: Acts of Parliament and statutory instruments; Literature on German law; and Bibliographies on German law. Additional resources include an internal search engine and related links. Some of the sections are still under development, and information for potential contributors to the archive is provided.

336

Federal Law Enforcement Statistics  

NSDL National Science Digital Library

Supplies census statistics about federal employees with law enforcement authority. Provides additional information about the functionality, budget, expenditures, and staffing of federal crime labs and police departments.

U.S. Department of Justice

337

Optical damage in KTN  

Microsoft Academic Search

An analysis of light-induced refractive-index changes (``optical damage'') has been carried out for paraelectric electro-optic crystals. The results are compared with experimental data taken on several KTN crystals. Both the spatial extent and temporal variations of optical damage are accurately determined by the theory for all crystals tested. The rate at which optical damage occurs can be used to determine

S. R. King; T. S. Hartwick; A. B. Chase

1972-01-01

338

Damage Tolerance of Composites  

NASA Technical Reports Server (NTRS)

Fracture control requirements have been developed to address damage tolerance of composites for manned space flight hardware. The requirements provide the framework for critical and noncritical hardware assessment and testing. The need for damage threat assessments, impact damage protection plans, and nondestructive evaluation are also addressed. Hardware intended to be damage tolerant have extensive coupon, sub-element, and full-scale testing requirements in-line with the Building Block Approach concept from the MIL-HDBK-17, Department of Defense Composite Materials Handbook.

Hodge, Andy

2007-01-01

339

The End of Negotiable Instruments: Bringing Payments Systems Law Out of the Past  

Microsoft Academic Search

In The End of Negotiable Instruments: Bringing Payments Systems Law Out of the Past, author James Rogers challenges the basic assumptions of the law of checks and notes and its history, and provides a well-reasoned account of how the law could be changed to better suit the evolution of new payment technologies.\\u000aThe modern American law of payment systems is

James S Rogers

2011-01-01

340

A damage mechanics based approach to structural deterioration and reliability  

SciTech Connect

Structural deterioration often occurs without perceptible manifestation. Continuum damage mechanics defines structural damage in terms of the material microstructure, and relates the damage variable to the macroscopic strength or stiffness of the structure. This enables one to predict the state of damage prior to the initiation of a macroscopic flaw, and allows one to estimate residual strength/service life of an existing structure. The accumulation of damage is a dissipative process that is governed by the laws of thermodynamics. Partial differential equations for damage growth in terms of the Helmholtz free energy are derived from fundamental thermodynamical conditions. Closed-form solutions to the equations are obtained under uniaxial loading for ductile deformation damage as a function of plastic strain, for creep damage as a function of time, and for fatigue damage as function of number of cycles. The proposed damage growth model is extended into the stochastic domain by considering fluctuations in the free energy, and closed-form solutions of the resulting stochastic differential equation are obtained in each of the three cases mentioned above. A reliability analysis of a ring-stiffened cylindrical steel shell subjected to corrosion, accidental pressure, and temperature is performed.

Bhattcharya, B.; Ellingwood, B. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

1998-02-01

341

THE LAW AND POLICY OF EARTHQUAKE HAZARD IN THE CENTRAL UNITED STATES  

E-print Network

1 THE LAW AND POLICY OF EARTHQUAKE HAZARD IN THE CENTRAL UNITED STATES Thomas B. Ginsburg Timothy D .................................................................................................................. 1 II. EARTHQUAKE RISK IN THE MIDWEST.............................................................. 6 C. Probability of Future Damaging Earthquakes

342

School Law Update...Preventive School Law.  

ERIC Educational Resources Information Center

A wide variety of contemporary legal issues are addressed in the 15 separate papers that make up this volume. The introductory chapter by William C. Bednar, Jr. provides a broad-based rationale for "Preventive School Law." Chapters 2 and 3, both by Gerald A. Caplan, review "Current Issues in Reduction-in-Force" and "First Amendment Claims by

Jones, Thomas N., Ed.; Semler, Darel P., Ed.

343

19 CFR 133.51 - Relief from forfeiture or liquidated damages.  

Code of Federal Regulations, 2010 CFR

... TRADEMARKS, TRADE NAMES, AND COPYRIGHTS Procedure Following Forfeiture...for violation of the trademark or copyright laws, or a claim for liquidated damages...manufacturing clause of the Copyright Act of 1976 (17 U.S.C....

2010-04-01

344

19 CFR 133.51 - Relief from forfeiture or liquidated damages.  

Code of Federal Regulations, 2011 CFR

... TRADEMARKS, TRADE NAMES, AND COPYRIGHTS Procedure Following Forfeiture...for violation of the trademark or copyright laws, or a claim for liquidated damages...manufacturing clause of the Copyright Act of 1976 (17 U.S.C....

2011-04-01

345

Modeling of glass fracture damage using continuum damage mechanics - Static spherical indentation  

SciTech Connect

Continuum damage mechanics based constitutive model is used to study the stone-impact resistance of automotive windshields. An axisymmetric finite element model is created to simulate the transient dynamic response and impact induced damge tensors for laminated glass layers subject to stone-impact loading. The windshield glass consists of two glass outer layers laminated by a thin poly-vinyl butyral (PVB) layer. The constitutive behavior of the glass layers is simulated suing continuum damage mechanics model with linear damage evolution. The PVB layer is modeled with linear viscoelastic solid. The model is used to predict and examine damage patterns on different glass surfaces for different windshield designs including variations in ply thickness and curvatures.

Sun, Xin; Khaleel, Mohammad A.

2004-07-01

346

College of Law LLM in Oil and Gas Law  

E-print Network

remains one of the most fundamental aspects of global commerce and natural resources law in the modern eraCollege of Law LLM in Oil and Gas Law New LLM in Oil and Gas Law launched to complement our other Law. The new LLM Degree in this field is a very exciting development at Swansea and I am sure

Martin, Ralph R.

347

Law 275 sec. 1 The Environmental Law Workshop  

E-print Network

Law 275 sec. 1 The Environmental Law Workshop (Spring 2005) Instructor: Daniel A. Farber Email: dfarber@law.berkeley.edu Location: 123 Boalt Time: Mondays 4:20-6:10 Syllabus Class 1 ­ January 10 Lecturer: Daniel Farber, Sho Sato Professor of Law, Director of Environmental Law Program (Boalt School

Kammen, Daniel M.

348

Centre for Business Law and Practice School of Law  

E-print Network

1 Centre for Business Law and Practice School of Law University of Leeds ANNUAL REPORT 2012 ­ 2013 AND THE CITY 1.1 THE CENTRE The Centre for Business Law and Practice (the `Centre') is located in the School of Law (part of the Faculty of Social Sciences, Education and Law) at the University of Leeds. The School

Berzins, M.

349

Kepler's Law of Refraction  

Microsoft Academic Search

In his review of the second volume of the new edition of Kepler's works in Nature of August 19, p. 306, Prof. H. C. Plummer states that Kepler's formula for the law of refraction is alpha - beta = kappaalpha sec beta, where alpha is the angle of incidence and beta the angle of refraction. This reduces to the law

R. A. Houstoun

1939-01-01

350

LawGuru.com  

NSDL National Science Digital Library

LawGuru.com is an exhaustive resource for free legal information. The site provides access to more than 430 legal search engines and databases, including a feature that allows parallel searching of multiple databases. The site also maintains the LawGuru.com BBS, a searchable database of legal questions posted by users accompanied by responses from one of the more than 320 practicing attorneys in the LawGuru.com network. Currently the BBS database contains over 4,000 legal questions divided into more than 25 categories. In addition, LawGuru.com provides a collection of fifteen FAQs written on various legal issues, links to over 500 legal Internet resources, and information on over 600 associated electronic mailing lists. Recently, LawGuru.com began hosting the Internet Law Library (see the May 3, 1996 Scout Report), a comprehensive resource formerly maintained by the US House of Representatives. LawGuru.com is operated by The Law Offices of Eslamboly & Barlavi (California).

351

The law and neuroscience.  

PubMed

Some of the implications for law of recent discoveries in neuroscience are considered in a new program established by the MacArthur Foundation. A group of neuroscientists, lawyers, philosophers, and jurists are examining issues in criminal law and, in particular, problems in responsibility and prediction and problems in legal decision making. PMID:18995814

Gazzaniga, Michael S

2008-11-01

352

California Library Laws, 2009  

ERIC Educational Resources Information Center

California Library Laws 2009 is a selective guide to state laws and related materials that most directly affect the everyday operations of public libraries and organizations that work with public libraries. It is intended as a convenient reference, not as a replacement for the annotated codes or for legal advice. The guide is organized as follows.

Smith, Paul G., Ed.

2009-01-01

353

Teaching Information Technology Law  

ERIC Educational Resources Information Center

In this paper we discuss an approach to the teaching of information technology law to higher education computing students that attempts to prepare them for professional computing practice. As information technology has become ubiquitous its interactions with the law have become more numerous. Information technology practitioners, and in particular

Taylor, M. J.; Jones, R. P.; Haggerty, J.; Gresty, D.

2009-01-01

354

Social Studies: Law Education.  

ERIC Educational Resources Information Center

Reviews 11 series, texts, supplements, kits, and professional references for law instruction, including civil and criminal law, the Bill of Rights, and controversial legal issues: arson, gun control, capital punishment, and euthanasia. While all grade levels are covered, the emphasis is on secondary-level materials. (SJL)

Curriculum Review, 1979

1979-01-01

355

School Law Update, 1986.  

ERIC Educational Resources Information Center

A wide variety of contemporary legal issues, involving all levels of public and private education, are addressed in the 20 separate chapters comprising this volume. The titles and authors of the chapters are as follows: (1) Due Process of Law: Loudermill v. Cleveland Board of Education (Hooker); (2) Schools, Technology and the Law (Helm); (3)

Jones, Thomas N., Ed.; Semler, Darel P., Ed.

356

California Library Laws, 2008  

ERIC Educational Resources Information Center

"California Library Laws 2008" is a selective guide to state laws and related materials that most directly affect the everyday operations of public libraries and organizations that work with public libraries. It is intended as a convenient reference, not as a replacement for the annotated codes or for legal advice. The guide is organized as

Smith, Paul G., Ed.

2008-01-01

357

Laws for Young Mountaineers.  

ERIC Educational Resources Information Center

This booklet introduces secondary grade students to the criminal laws of West Virginia. It can easily be adapted and used by educators in other states. The authors believe that young people must recognize and understand these laws and the mechanisms which society uses to implement and enforce them if they are to function as an integral, important,

Kanawha County Board of Education, Charleston, WV.

358

Seattle University Law Review  

NSDL National Science Digital Library

Originally published as the University of Puget Sound Law Review, this particular legal institution became part of Seattle University in 1994. The Seattle University Law Review "strives to publish articles that will be useful research tools for students, attorneys, judges, and legal scholars," with articles on a range of legal topics, including family law, copyright law, and other topics. On the homepage, visitors can read over the Aims & Scope to learn about the main mission, sign up for Facebook updates, and also review the editorial board. Visitors can use the drop-down menu to browse past issues, or use the search engine to find specific topics or phrases of interest. There are a number of special issues here, including "Symposium on Racial Bias and the Criminal Justice System" and "A Symposium Celebrating the Launch of the Adolf A. Berle, Jr. Center on Corporations, Law & Society."

2012-09-21

359

Duke Law & Technology Review  

NSDL National Science Digital Library

Law school students are well known for trying to "do good" whether it be through aiding wrongly accused persons, or by providing legal advice at any number of free clinics. This academic and policy-oriented online publication from the people at Duke University's Law School is another such endeavor, and one that is worth a closer look. The publication's general area of interest is in the intersection of law and technology, and as such it draws on the knowledge base of specialties that include business law and intellectual property. The school's Law & Technology Review consists primarily of short issues briefs that provide insight into a wide range of issues for both the legal community and professionals working in these areas more broadly. Visitors to the site can browse the different briefs through a listing of general thematic areas or merely scroll through the site's homepage.

360

Florida Law Collections  

NSDL National Science Digital Library

The Florida Law Collections document the laws and legal heritage of Florida through a wide range of texts digitized from the holdings of the University of Florida's Lawton Chiles Legal Information Center, the State Library, and Archives of Florida, and several other key institutions. Specifically, the collection includes issues of the Journal of the Florida House of Representatives, the Florida Historical Legal Documents collection, a Florida Water Law collection that is particularly noteworthy, as well as other general texts on Florida laws, the legislative process, and government. Given the debates over water rights and usage throughout the state, the Water Law collection is a real find, and visitors can search over 7300 documents within the collection. From the homepage, visitors can perform advanced searches and also look over recently added items. Finally, visitors can also sign up to receive their RSS feed and contact the site administrators with any additional queries they might have.

361

Constitutive modeling of viscoplastic damage in solder material  

SciTech Connect

This paper presents a constitutive modeling of viscoplastic damage in 63Sn-37Pb solder material taking into account the effects of microstructural change in grain coarsening. Based on the theory of damage mechanics, a two-scalar damage model is developed by introducing the damage variables and the free energy equivalence principle. An inelastic potential function based on the concept of inelastic damage energy release rate is proposed and used to derive an inelastic damage evolution equation. The validation of the model is carried out for the viscoplastic material by predicting monotonic tensile behavior and tensile creep curves at different temperatures. The softening behavior of the material under monotonic tension loading can be characterized with the model. The results demonstrate adequately the validity of the proposed viscoplastic constitutive modeling for the solder material.

WEI,YONG; CHOW,C.L.; NEILSEN,MICHAEL K.; FANG,HUEI ELIOT

2000-04-17

362

Ischemia-Reperfusion Damage  

PubMed Central

Ischemia-reperfusion damage is a complex pathological process that begins with tissue anoxia and continues with the production of free oxygen radicals, expanding with the inflammatory response. The literature suggests the importance of antioxidant and anti-inflammatory treatment to treat ischemia-reperfusion-related tissue damage.

Yapca, Omer E.; Borekci, Bunyamin; Suleyman, Halis

2013-01-01

363

Evolution of cooperation in finite populations  

E-print Network

of cooperation in nature 2. Prisoner's Dilemma 3. Evolutionary dynamics in an infinite population 4. FixationEvolution of cooperation in finite populations Sabin Lessard Universit´e de Montr´eal Title probability in a finite population 5. Generalized one-third law of evolution 6. Projected average excess

Lessard, Sabin

364

LAW / DROIT Connecting students, professors  

E-print Network

LAW / DROIT AUTOMNE FALL / 2014 Faculty of Law Faculté de droit BRANCH? Connecting students, professors and alumni as they explore new horizons in legal education and practice #12;II FOCUS | LAW ­ FALL Conferences & Special Events Coordinator Alumnioffice.law@mcgill.ca Telephone: 514 398-3679 Focus Law est

Kambhampati, Patanjali

365

POSTGRADUATE GUIDE SCHOOL OF LAW  

E-print Network

POSTGRADUATE GUIDE SCHOOL OF LAW www.abdn.ac.uk/law #12;Set in the heart of Europe's Energy Capital Over 500 years of teaching and research excellence A top UK Law School Dedicated Law Library containing and the world. Law has been taught at the University since its foundation. Today, the School ranks among the UK

Levi, Ran

366

Accepting Evolution or Discarding Science  

ERIC Educational Resources Information Center

Challenging basic principles of constitutional law, advocates of intelligent design are undermining educators' ability to teach evolution in their science classrooms. Because US Supreme Court rulings now prohibit creationist accounts of the origin of life in schools, arguments favoring divine intervention, known as intelligent design, have emerged

Sharpes, Donald K.; Peramas, Mary M.

2006-01-01

367

43 CFR 9239.0-8 - Measure of damage.  

Code of Federal Regulations, 2011 CFR

...resources, coal, oil, and other trespass in accordance with the decision of the Supreme Court of the United States in the case of Mason et al. v. United States (260 U.S. 545, 67 L. ed. 396), will be the measure of damages prescribed by the laws...

2011-10-01

368

The new energy law  

SciTech Connect

Foreign companies, as well as Polish companies, have long awaited the introduction of a new environment for doing business in Poland`s energy sector. The adoption by the Sejm (lower house of the Polish Parliament) of a new Energy Law (Prawo Energetyczne) promises to move Poland into a brave new world for energy sector businesses. With this law, Poland hopes to leapfrog into the vanguard of European countries in terms of privatization and demonopolization of its energy sectors. Only the United Kingdom may be more progressive in this regard. During the past several months, a draft law was passed by the Sejm and sent to the Senate. The Senate introduced nearly 50 changes, passed the law and returned it to the Sejm. At that point, the Sejm committee responsible for this law recommended against almost all the Senate`s changes, returning the draft law to its original form. The actions by the Sejm, now awaited, will be final with only the signature of the president needed to put the law into force. Subsequently, this examination of the law is based upon the draft as originally passed by the Sejm and expected to be signed by Poland`s president. There are several key provisions of the proposed new law that make it so different from the current regulatory structure. The key terms that the Polish government likes to use are privatization and demonopolization, of which the latter is to come first. It is a leap forward from an energy sector that was owned entirely by the State, and where prices at all levels, from the coal mines to the residential consumer, were set without regard to cost.

Allen, Z.

1997-05-01

369

FindLaw Constitutional Law Center  

NSDL National Science Digital Library

This offering from FindLaw (last discussed in the January 15, 1999 Scout Report) focuses on the US Constitution. The site is composed of two primary sections. The first offers an annotated Constitution, commentary on selected topics with links to key sections of the Constitution or The Federalist Papers, a history of the Constitution, and brief biographies of notable "Founding Fathers" and delegates to the Constitutional Convention. The second section highlights the Third Branch of government, with a history of the Supreme Court, landmark decisions regarding civil rights with the full opinions, a summary and analysis of the criminal law and procedure decisions of the October 1998 Supreme Court Term, and several links for current Supreme Court news and information. Both sections also feature a search engine. Additional resources at the site include a Town Hall section that explores Hot Topics (currently flag burning) and message boards on a wide variety of Constitutional issues.

1994-01-01

370

FindLaw Constitutional Law Center  

NSDL National Science Digital Library

This latest offering from FindLaw (last discussed in the January 15, 1999 Scout Report) focuses on the US Constitution. The site is composed of two primary sections. The first offers an annotated Constitution, commentary on selected topics with links to key sections of the Constitution or The Federalist Papers, a history of the Constitution, and brief biographies of notable "Founding Fathers" and delegates to the Constitutional Convention. The second section highlights the Third Branch of government, with a history of the Supreme Court, landmark decisions regarding civil rights with the full opinions, a summary and analysis of the criminal law and procedure decisions of the October 1998 Supreme Court Term, and several links for current Supreme Court news and information. Both sections also feature a search engine. Additional resources at the site include a Town Hall section that explores Hot Topics (currently flag burning) and message boards on a wide variety of Constitutional issues.

371

Preservation Concerns for Law Libraries - Results from the Condition Survey of the University of Kansas Law Library  

E-print Network

Libraries (%) Law Library (%) In Good Condition 85.70 82.88 Remain in Stacks 8.94 12.94 Damaged Spine 5.68 3.97 Loose Joints 4.48 6.26 Damaged Inner Joints 4.40 4.38 Damaged Paper Cover 1.28 1.67 Cover off Volume 0.76 0.21 Red-Rot Leather 1.11 5.85 Title... condition 90.84 94.36 Remain in stacks 20 3.59 1.67 Broken or loose sewing or adhesive 3.40 0.42 Broken text block 1.55 0.00 Loose pages 1.90 1.67 Damaged pages (not mutilation) 2.88 0.42 Missing pages (not mutilation) 0.08 0.21 Pages damaged or curled from...

Mead, Robert A.

2003-01-01

372

Dynamics and Adaptive Control for Stability Recovery of Damaged Aircraft  

NASA Technical Reports Server (NTRS)

This paper presents a recent study of a damaged generic transport model as part of a NASA research project to investigate adaptive control methods for stability recovery of damaged aircraft operating in off-nominal flight conditions under damage and or failures. Aerodynamic modeling of damage effects is performed using an aerodynamic code to assess changes in the stability and control derivatives of a generic transport aircraft. Certain types of damage such as damage to one of the wings or horizontal stabilizers can cause the aircraft to become asymmetric, thus resulting in a coupling between the longitudinal and lateral motions. Flight dynamics for a general asymmetric aircraft is derived to account for changes in the center of gravity that can compromise the stability of the damaged aircraft. An iterative trim analysis for the translational motion is developed to refine the trim procedure by accounting for the effects of the control surface deflection. A hybrid direct-indirect neural network, adaptive flight control is proposed as an adaptive law for stabilizing the rotational motion of the damaged aircraft. The indirect adaptation is designed to estimate the plant dynamics of the damaged aircraft in conjunction with the direct adaptation that computes the control augmentation. Two approaches are presented 1) an adaptive law derived from the Lyapunov stability theory to ensure that the signals are bounded, and 2) a recursive least-square method for parameter identification. A hardware-in-the-loop simulation is conducted and demonstrates the effectiveness of the direct neural network adaptive flight control in the stability recovery of the damaged aircraft. A preliminary simulation of the hybrid adaptive flight control has been performed and initial data have shown the effectiveness of the proposed hybrid approach. Future work will include further investigations and high-fidelity simulations of the proposed hybrid adaptive Bight control approach.

Nguyen, Nhan; Krishnakumar, Kalmanje; Kaneshige, John; Nespeca, Pascal

2006-01-01

373

Benford's Law in Astronomy  

NASA Astrophysics Data System (ADS)

Benford's law predicts the occurrence of the n-th digit of numbers in datasets originating from various sources all over the world, ranging from financial data to atomic spectra. It is intriguing that although many features of Benford's law have been proven, it is still not fully understood mathematically. In this paper we investigate the distances of galaxies and stars by comparing the first, second and third significant digit probabilities with Benford's predictions. It is found that the distances of galaxies follow the first digit law reasonable well, and that the star distances agree very well with the first, second and third significant digit.

Alexopoulos, Theodoros; Leontsinis, Stefanos

2014-07-01

374

International Constitutional Law (ICL)  

NSDL National Science Digital Library

Hosted by the University of Wuerzburg (Germany), International Constitutional Law (ICL) provides English texts of constitutional documents and links to background information on over seventy countries. Documents are cross-referenced for comparison of constitutional provisions. Also featured are links to Constitutional Court sites, a Model Constitutional Code, a section on German Case Law, a comprehensive list of international organizations, and a strong collection of links to constitutional and international law and constitution sites. The material available at ICL is widely applicable to fields such as political science, international relations, or government, and could be very useful for research projects in both secondary and university classrooms.

1997-01-01

375

The LSU Law Center -- Canada Bijuralism Conference. Introduction: Global Law and the Law School Curriculum.  

ERIC Educational Resources Information Center

Introduces papers from a conference focused on the bijural programs of Louisiana State University Law Center and McGill University Faculty of Law. The programs educate all first-degree law students in both the common law and civil law traditions, preparing them for the increasing globalization of legal practice. (EV)

Costonis, John J.

2002-01-01

376

Law School Admissions Panel Law School representatives will discuss the law school admissions  

E-print Network

Law School Admissions Panel Law School representatives will discuss the law school admissions process and talk about their respective schools in a panel discussion format. Join us and learn how in Law School Admissions Panel epresentatives will discuss the law school admissions process and talk

Brinkmann, Peter

377

Law Enforcement and the Library.  

ERIC Educational Resources Information Center

Presents information on law enforcement relating to library crimes. Discusses jurisdiction, reporting a loss, law enforcement response, law enforcement's expectations, suspects, publicity, the aftermath, and testimony in court. (AEF)

Clark, Edward F.

1998-01-01

378

Laser Damage Lab  

NASA Technical Reports Server (NTRS)

Optical Damage Threshold Testing Instrumentation at NASA Langley Research Center. This work was sanctioned and funded by Code Q, R, & AE to develop a new standard for damage testing various types of optical materials and coatings. Laser Induced Damage Threshold (LIDT) testing is a destructive test procedure to determine the minimum applied laser energy level that will result in damage and is referred to as the damage threshold. The damage threshold is often the critical limitation in the section of optical materials for use in high-energy laser systems.The test station consists of diagnostic equipment, beam conditioning optical elements, an inspection microscope and three lasers: a high energy pulsed ND: Yag, which develops 650mJ at 10 hz and outputs three wavelengths which include 1.06m, 532nm and 355 nm; a Ti:sapphire laser which produces a continuum of laser output from 790nm to 900nm; and a alignment HeNe, which looks yellow when mixed with the 2nd harmonic ND:Yag laser. Laser sources are used to perform damage threshold testing at the specific wavelength of interest.

1993-01-01

379

2003 The Society for the Study of Evolution. All rights reserved. INTERNATIONAL JOURNAL OF ORGANIC EVOLUTION  

E-print Network

STEVEN A. FRANK1 Department of Ecology and Evolutionary Biology, University of California, Irvine evolution, symbiosis. Received April 23, 2002. Accepted November 27, 2002. The function of laws beneficial effects to those . . . that propose, main- tain, adjust, and enforce the laws. (Alexander 1979, p

Frank, Steven A.

380

The Child Abuse Reporting Law. Protecting Children Becomes a Broader Community Responsibility. 2d Edition.  

ERIC Educational Resources Information Center

North Carolina's Child Abuse Reporting Law makes all citizens legally responsible for reporting incidents of child abuse and neglect. Professionals, such as doctors and teachers, must also give their professional opinions as to the nature, extent, and causes of the damaged child's condition. The basic purpose of the law is to identify children at

Thomas, Mason P., Jr.

381

Non standard thermodynamics framework for robust computations with induced anisotropic damage  

E-print Network

. The elasticity law and the strain energy release rate density YYY , variable associated with DDD- tential quadratic function of YYY is most often considered, the damage law taking the form DDD = JJJ : YYY (1) with a positive multiplier and JJJ a positive fourth order tensor, eventually nonlinear

382

War Damage Assessment  

NASA Technical Reports Server (NTRS)

During and after the Persian Gulf war, hundreds of "oil lakes" were created in Kuwait by oil released from damaged wells. The lakes are a hazard to the Kuwait atmosphere, soil and ground water and must be carefully monitored. Boston University Center for Remote Sensing, assisted by other organizations, has accurately mapped the lakes using Landsat and Spot imagery. The war damage included the formation of over 300 oil lakes, oil pollution and sand dune movement. Total damage area is over 5,400 square kilometers - 30 percent of Kuwait's total surface area.

1994-01-01

383

Assessing tubal damage  

PubMed Central

The fallopian tube plays an important role in the mechanical transport and physiological sustenance of the gametes and early conceptus. Complex and coordinated neuromuscular activity, cilial action and endocrine secretions are required for successful tubal function. Compromised tubal damage can occur after external or internal injury, inhibiting the normal transport of gametes. The overall prognosis for fertility depends principally on the insult and the severity of the tissue damage; hence, assessment of tubal damage plays a major role in predicting occurrence of pregnancy and the likelihood of developing ectopic pregnancy. PMID:19562067

Patil, Madhuri

2009-01-01

384

Initiation of plate tectonics, damage and inheritance  

NASA Astrophysics Data System (ADS)

The initiation of plate tectonics on Earth is a critical event in our planet's history. The time lag between the first proto subduction about 4Ga to global tectonics by 3Ga, suggests that plates and plate boundaries became widespread over a 1Gyr period. We hypothesize that during this period, transient mantle flow and migrating proto-subductions lead to lithospheric damage and eventually fully formed tectonic plates driven by subduction alone. We demonstrate this process using a grain evolution and damage mechanism (Bercovici and Ricard, 2012) with a composite rheology, which are compatible with field and laboratory observations of polycrystalline rocks coupled to an idealized model of pressure-driven lithospheric flow (wherein a low pressure zone is equivalent to the suction of convective downwellings). In the simplest case, for Earth-like conditions, a few successive rotations of the driving pressure field yield relic damage zones that are inherited to form a nearly perfect plate, with passive spreading and strike-slip margins that persist and localize further, even as flow is only driven by subduction. For Venus hotter surface conditions, accumulation and inheritance of damage is negligible; hence only subduction zones survive and plate tectonics does not spread, which corresponds to observations. After plates are developed, continued changes in driving forces, combined with inherited damage and weak zones, promote increased tectonic complexity, such as oblique subduction, strike-slip boundaries that are subparallel to plate motion, and spalling of minor plates.

Ricard, Yanick; Bercovici, David

2014-05-01

385

Nonlinear damage analysis: Postulate and evaluation  

NASA Technical Reports Server (NTRS)

The objective of this program is to assess the viability of a damage postulate which asserts that the fatigue resistance curve of a metal is history dependent due to inelastic action. The study focusses on OFE copper because this simple model material accentuates the inelastic action central to the damage postulate. Data relevant to damage evolution and crack initiation are developed via a study of surface topography. The effects of surface layer residual stresses are explored via comparative testing as were the effects in initial prestraining. The results of the study very clearly show the deformation history dependence of the fatigue resistance of OFE copper. Furthermore the concept of deformation history dependence is shown to qualitatively explain the fatigue resistance of all histories considered. Likewise quantitative predictions for block cycle histories are found to accurately track the observed results. In this respect the assertion that damage per cycle for a given level of the damage parameter is deformation history dependent appears to be physically justified.

Leis, B. N.; Forte, T. P.

1983-01-01

386

Laws of Motion  

NSDL National Science Digital Library

The representation depicts a truck with a ladder on its roof stopping quickly so that the ladder is thrown from the top of the truck. The representation is contained within a slide show explaining Newton's 1st Law of Motion.

387

The "Natural Law Tradition."  

ERIC Educational Resources Information Center

A discussion of natural law outlines some of the theory and tradition surrounding it and examines its relationship to the social science and legal curriculum and to the teaching of jurisprudence. (MSE)

Finnis, John

1986-01-01

388

Business Law Today  

NSDL National Science Digital Library

The American Bar Association has recently begun to provide full text of this bimonthly magazine covering various aspects of business law. In addition to feature articles, there are five small sections with snippets of legal news and features.

1995-01-01

389

Business Law Today  

NSDL National Science Digital Library

The American Bar Association has recently begun to provide full text of this bimonthly magazine covering various aspects of business law. In addition to feature articles, there are five small sections with snippets of legal news and features.

2007-04-19

390

What Is Benford's Law?  

ERIC Educational Resources Information Center

The surprising property of many data sets that their first significant digits follow Benford's Law provides examples that can pique and hold students' interest. Several ideas for student activities are presented.

Bradley, Jonathan R.; Farnsworth, David L.

2009-01-01

391

The Abortion Law Homepage  

NSDL National Science Digital Library

This privately posted page offers extensive and highly credible information on legislation and jurisprudence relating to abortion in the US. The site offers thoroughly linked discussions of constitutional law, Roe v. Wade, Planned Parenthood v. Casey, state and federal abortion laws, including partial-birth abortion laws, and much more. The hypertext links are to primary documents including court decisions, texts of legislation, court briefs, and oral argument transcripts. There is also an index to primary documents for ease of access. We found the page to have no political agenda. As the author states, "this page is being constructed to help people, regardless of their political bent, understand the background and state of abortion law in America, and access related legal material--especially that which is less available and less well known."

392

Newton's Laws of Motion  

NSDL National Science Digital Library

This series of web pages, part of From Stargazers to Starships, describes Newton's three laws of motion and the two concepts on which they are based, force and inertia. A lesson plan for instructors is also provided.

Dr. David P. Stern

2004-10-09

393

The Biogenetic Law  

ERIC Educational Resources Information Center

A criterion for development of syllabi for mathematics courses is discussed. This criterion is based on the biogenetic law that individuals develop through all the stages of the development of the species. (SD)

Kapadia, Ramesh

1975-01-01

394

Drunk Driving Laws  

MedlinePLUS

... Offense Limited Driving Privileges During Susp. Ignition Interlocks Vehicle and License Plate Sanctions Open Container Laws* Repeat ... days After 30 days Mandatory for all convictions Vehicle impoundment Yes Ariz. .15 90 days After 30 ...

395

Law Enforcement Technology  

NSDL National Science Digital Library

Serving as a sworn officer of the law continues to be one of the most demanding professions in the country, and those in the field will certainly appreciate the website of Law Enforcement Technology. This monthly magazine concentrates primarily on the emerging trends in the field of law enforcement technology, such as the use of computers, refined body armor designs, and of course, improvements in weaponry and forensics. On their website, visitors can read articles about new data management systems, mobile license plate readers, and innovative flashlights. Along with these feature articles, each issue contains information about funding opportunities for law enforcement technology initiatives and new developments in software technology. Finally, visitors can also sign up to receive email notifications about job opportunities and promotional offers.

396

Potential Conservation Laws  

E-print Network

We prove that potential conservation laws have characteristics depending only on local variables if and only if they are induced by local conservation laws. Therefore, characteristics of pure potential conservation laws have to essentially depend on potential variables. This statement provides a significant generalization of results of the recent paper by Bluman, Cheviakov and Ivanova [J. Math. Phys., 2006, V.47, 113505]. Moreover, we present extensions to gauged potential systems, Abelian and general coverings and general foliated systems of differential equations. An example illustrating possible applications of proved statements is considered. A special version of the Hadamard lemma for fiber bundles and the notions of weighted jet spaces are proposed as new tools for the investigation of potential conservation laws.

Michael Kunzinger; Roman O. Popovych

2008-03-07

397

Potential conservation laws  

SciTech Connect

We prove that potential conservation laws have characteristics depending only on local variables if and only if they are induced by local conservation laws. Therefore, characteristics of pure potential conservation laws have to essentially depend on potential variables. This statement provides a significant generalization of results of the recent paper by Bluman et al. [J. Math. Phys. 47, 113505 (2006)]. Moreover, we present extensions to gauged potential systems, Abelian and general coverings, and general foliated systems of differential equations. An example illustrating possible applications of these results is given. A special version of the Hadamard lemma for fiber bundles and the notions of weighted jet spaces are proposed as new tools for the investigation of potential conservation laws.

Kunzinger, Michael [Fakultaet fuer Mathematik, Universitaet Wien, Nordbergstrasse 15, A-1090 Wien (Austria); Popovych, Roman O. [Fakultaet fuer Mathematik, Universitaet Wien, Nordbergstrasse 15, A-1090 Wien (Austria); Institute of Mathematics, NAS of Ukraine, 3 Tereshchenkivska Str., Kyiv-4 (Ukraine)

2008-10-15

398

Stokes' Law Revisited  

ERIC Educational Resources Information Center

Discusses limitations and corrections to be made in physics experiments involving the investigations of drag and terminal velocity on spheres falling through a liquid in accordance with Stokes' law. (SL)

Wray, E. M.

1977-01-01

399

AJ Ohm's Law Calculator  

NSDL National Science Digital Library

The electrical relationships between resistance (R), current (I), power (P) and voltage (E) is defined by Ohm's Law. One ohm is defined as the resistance which allow the current of one ampere under a potential difference of 1 volt.

Raymond, Jimmy

400

Modeling Incipient Copper Damage Data from the Tensile Hopkinson Bar and Gas Gun  

Microsoft Academic Search

Ductile damage in copper has been created using a split tensile Hopkinson pressure bar. Precise momentum trapping has made it possible to arrest the damage after a short tensile pulse before complete fracture. This process has been modeled with a void nucleation and growth law. 2D calculations have been performed to compare with final porosity and void number density data.

D. L. Tonks; W. R. Thissell; D. S. Schwartz

2004-01-01

401

A Guide to F-Scale Damage Assessment U.S. DEPARTMENT OF COMMERCE  

E-print Network

.............................................................................................................iii I. The Fujita scale of tornado intensityA Guide to F-Scale Damage Assessment U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric of the copyright holders. Federal Law provides copyright protection of these images. #12;A Guide to F-Scale Damage

Doswell III, Charles A.

402

College of Business School of Law  

E-print Network

expertise in International Law, Natural Resource Law, Disaster Management & Criminal Law. #12;School of LawCollege of Business and Law School of Law Strategic Objectives 2013-2015 #12;School of Law: · Top 100 Law School in the world ­ QS 2013 · 2003-2006 PBRF No 1 law school in NZ (Quality Score of 5

Hickman, Mark

403

Comparison of GTN damage models for sheet metal forming  

Microsoft Academic Search

The Gurson-Tvergaard-Needleman (GTN) damage model was developed basing on anisotropic yield criterion to predict the damage\\u000a evolution for anisotropic voided ductile materials. Hills quadratic anisotropic yield criterion (1948) and Barlats 3-component\\u000a anisotropic yield criterion (1989) were used to describe the anisotropy of the matrix. User defined subroutines were developed\\u000a using the above models. Taking the benchmark of NUMISHEET93 square cup

Zhi-ying Chen; Xiang-huai Dong

2008-01-01

404

Law & Politics Internet guide  

NSDL National Science Digital Library

This metasite of law and political resources is designed for legal professionals, academics, and the general public. About two dozen lists of annotated links cover topics such as Legal Portals, Legal Resources, Foreign & International Law, and Legal Research. Equipped with language translation software (which works well on some pages but seems to cause graphics problems on other pages), the site is well designed and easy to use.

405

Power-laws and Non-Power-laws in Dark Matter Halos  

E-print Network

Simulated dark matter profiles are often modelled as a `NFW' density profile rather than a single power law. Recently, attention has turned to the rather rigorous power-law behaviour exhibited by the `pseudo phase-space density' of the dark matter halo, which is defined dimensionally in terms of the local density and velocity dispersion of the dark matter particles. The non-power-law behaviour of the density profile is generally taken to exclude simple scale-free, in-fall models; however the power-law behaviour of the `pseudo-density' is a counter indication. We argue in this paper that both behaviours may be at least qualitatively understood in terms of a dynamically evolving self-similarity, rather than the form for self-similar infall that is fixed by cosmological initial conditions. The evolution is likely due to collective relaxation such as that provided by the radial-orbit instability on large scales. We deduce, from a distribution function given by first order coarse-graining, both the NFW-type density profile and the power-law pseudo-density profile. The results are not greatly sensitive to variation about 3 in the power of the velocity dispersion used in the definition of the phase space pseudo-density. We suggest that the power 2 may create the more physical quantity, whose deviations from a power-law are a diagnostic of incomplete relaxation.

R. N. Henriksen

2006-09-05

406

Nonlocal conservation laws and related Bcklund transformations via reciprocal transformations  

E-print Network

A set of infinitely many nonlocal conservation laws are revealed for (1+1)-dimensional evolution equations. For some special known integrable systems, say, the KdV and Dym equations, it is found that different nonlocal conservation laws can lead to same new integrable systems via reciprocal transformation. On the other hand, it can be considered as one solution of the new model obtained via reciprocal transformation(s) can be changed to different solutions of the original model. The fact indicates also that two or more different (local and nonlocal) conservation laws can be used to find implicit auto-B\\"acklund transformations via reciprocal transformation to other systems.

Sen-Yue Lou

2014-06-08

407

The Evolution and Development of the Universe  

E-print Network

This document is the Special Issue of the First International Conference on the Evolution and Development of the Universe (EDU 2008). Please refer to the preface and introduction for more details on the contributions. Keywords: acceleration, artificial cosmogenesis, artificial life, Big Bang, Big History, biological evolution, biological universe, biology, causality, classical vacuum energy, complex systems, complexity, computational universe, conscious evolution, cosmological artificial selection, cosmological natural selection, cosmology, critique, cultural evolution, dark energy, dark matter, development of the universe, development, emergence, evolution of the universe evolution, exobiology, extinction, fine-tuning, fractal space-time, fractal, information, initial conditions, intentional evolution, linear expansion of the universe, log-periodic laws, macroevolution, materialism, meduso-anthropic principle, multiple worlds, natural sciences, Nature, ontology, order, origin of the universe, particle hierarchy, philosophy, physical constants, quantum darwinism, reduction, role of intelligent life, scale relativity, scientific evolution, self-organization, speciation, specification hierarchy, thermodynamics, time, universe, vagueness.

Clement Vidal; Charles Auffray; Alex H. Blin; Jean Chaline; Louis Crane; Thomas Durt; Borje Ekstig; Horace Fairlamb; Jan Greben; Rob Hengeveld; Francis Heylighen; Gerard Jagers op Akkerhuis; Giuseppe Longo; Nicolas F. Lori; Denis Noble; Laurent Nottale; Franc Rottiers; Stanley Salthe; John Stewart; Ruediger Vaas; Gertrudis Van de Vijver; Nico M. van Straalen

2010-01-04

408

Controlling Mole Damage  

E-print Network

Moles can cause much damage to crops and livestock. This leaflet explains the proper way to set shocker loop traps and harpoon traps. Cultural controls and habitat modifications are discussed. Moles also can be controlled with toxicants...

Texas Wildlife Services

2007-03-13

409

Northridge, CA Earthquake Damage  

USGS Multimedia Gallery

The person in this image was a USGS employee at the time this was taken. Collection of USGS still images taken after the January 17, 1994 Northridge earthquake highlighting the damage to buildings and infrastructure....

410

Composite heat damage assessment  

SciTech Connect

The effects of heat damage were determined on the residual mechanical, physical, and chemical properties of IM6/3501-6 laminates, and potential nondestructive techniques to detect and assess material heat damage were evaluated. About one thousand preconditioned specimens were exposed to elevated temperatures, then cooled to room temperature and tested in compression, flexure, interlaminar shear, shore-D hardness, weight loss, and change in thickness. Specimens experienced significant and irreversible reduction in their residual properties when exposed to temperatures exceeding the material upper service temperature of this material (350{degrees}F). The Diffuse Reflectance Infrared Fourier Transform and Laser-Pumped Fluorescence techniques were found to be capable of rapid, in-service, nondestructive detection and quantitation of heat damage in IM6/3501- 6. These techniques also have the potential applicability to detect and assess heat damage effects in other polymer matrix composites.

Janke, C.J.; Wachter, E.A. [Oak Ridge National Lab., TN (United States); Philpot, H.E. [Oak Ridge K-25 Site, TN (United States); Powell, G.L. [Oak Ridge Y-12 Plant, TN (United States)

1993-12-31

411

LSD and Genetic Damage  

ERIC Educational Resources Information Center

Reviews studies of the effects of lysergic acid diethylamide (LSD) on man and other organisms. Concludes that pure LSD injected in moderate doses does not cause chromosome or detectable genetic damage and is not a teratogen or carcinogen. (JM)

Dishotsky, Norman I.; And Others

1971-01-01

412

Controlling Armadillo Damage  

E-print Network

Armadillos are beneficial because they eat insects and other invertebrates, but they can damage lawns, gardens and structural foundations. They also are believed to transmit leprosy to humans. This leaflet focuses on control methods such as trapping...

Texas Wildlife Services

2007-03-13

413

Rate Tornado Damage  

NSDL National Science Digital Library

Tornadoes can produce damage that ranges from broken tree limbs to a block of houses swept from their foundations. They can inflict utter devastation across a wide swath of land or, destroy one house and leave others on either side largely untouched. In this interactive feature from NOVA Online, sudents examine a series of photos of tornado damage and assign intensity ratings (on the Fulita scale) based on what they see.

2011-02-24

414

Rate Tornado Damage  

NSDL National Science Digital Library

An interactive Flash animation that educates students about the Fujita scale for rating tornado wind speeds and the damage caused by tornados. After being presented with photographs of tornado damage, students are challenged to assign the tornado a rating on the F-scale. The interactive explains the different levels of the F-scale and provides instant feedback on whether or not the correct category was assigned to the tornado.

Lexi Krock

415

Rate Tornado Damage  

NSDL National Science Digital Library

Tornadoes can produce damage that ranges from broken tree limbs to a block of houses swept from their foundations. They can inflict utter devastation across a wide swath of land or, destroy one house and leave others on either side largely untouched. In this interactive feature from NOVA Online, sudents examine a series of photos of tornado damage and assign intensity ratings (on the Fulita scale) based on what they see.

416

Simulation of Self-Repair Process of Steels Damaged by Creep  

NASA Astrophysics Data System (ADS)

The continuum damage mechanics is extended to cover the self-repair process as well as the damage process. The repair variable and its evolution equation are newly introduced to consider the repair process. In the constitutive modeling, the equation of creep based on kinematic/isotropic hardening theory is extended to take the effect of damage into account. The evolution equation of a repair variable is proposed, based on Dyson's equation of creep cavity growth. The validity of the proposed modeling is illustrated through the simulations for the self-repair process of two kinds of steels damaged by creep.

Toi, Yutaka; Hirose, Satoshi

417

Kepler's Laws, Newton's Laws, and the Search for New Planets  

Microsoft Academic Search

Introduction. One of the high points of elementary calculus is the derivation of Ke- pler's empirically deduced laws of planetary motion from Newton's Law of Gravity and his second law of motion. However, the standard treatment of the subject in calcu- lus books is flawed for at least three reasons that I think are important. First, Newton's Laws are used

Robert Osserman

418

Rediscovering Kepler's laws using Newton's gravitation law and NASA data  

Microsoft Academic Search

Kepler's three laws of planetary motion were originally discovered by using data acquired from Tycho Brache's naked eye observations of the planets. We show how Kepler's third law can be reproduced using planetary data from NASA. We will also be using Newton's Gravitational law to explain why Kepler's three laws exist as they do.

Paul Springsteen; Jason Keith

2010-01-01

419

The Law of Hazardous Waste: CERCLA, RCRA, & Common Law Claims  

E-print Network

Law 273.4 The Law of Hazardous Waste: CERCLA, RCRA, & Common Law Claims (Fall 2006) Units: 3 CCN (2 of Hazardous Waste Disposal and Remediation (2d ed. 2005) Syllabus Class 1 ­ August 22 Claims Based on Common: 1. Miller & Johnston The Law of Hazardous Waste Disposal and Remediation 2. Ch. III, Intro to RCRA

Kammen, Daniel M.

420

Hyperbolic Conservation Laws The 1D conservation law  

E-print Network

Hyperbolic Conservation Laws The 1D conservation law wt + f(w)x = 0 (where w and f have m of linearly independent eigenvectors). Then solutions to the conservation law can be viewed in terms to form a complete linearly independent set, and the conservation law is called strictly hyperbolic

Gardner, Carl

421

BIODIVERSITY LAW PROFESSOR BIBER LAW 271.2 FALL 2009  

E-print Network

BIODIVERSITY LAW PROFESSOR BIBER LAW 271.2 FALL 2009 Handout #1 ­ 8/17/09 SYLLABUS MATERIALS The casebook for this course is David D. Goble and Eric T. Freyfogle, Wildlife Law: Cases and Materials (2002 the following sources: (a) Lexis or Westlaw (b) Hein on-line (available at http://www.law

Kammen, Daniel M.

422

[Environmental damage assessment: international regulations and revelation to China].  

PubMed

As the whole society gradually realizes the scarcity of nature resources and environmental value, countries all over the world have evolved and improved the system of environmental damage assessment through the practices of pollution prevention and ecological environmental protection. On one hand, in the research prospective, the practices of environmental damage assessment brought new challenges to environmental law, environmental economics, environmental science, environmental engineering, etc. On the other hand, they constantly promoted and developed relevant laws and regulations, techniques, working mechanism, and guidelines on procedure in practice. On the hasis of comparison and analysis of international practices and experiences from US, EU, and Japan, etc., this article identified relevant concepts, content, and scope of environmental damage assessment, and presented its scientific positioning and development direction. At present, both theory and practice of environmental damage assessment in China are in their infancy period. Considering current environmental situation and socioeconomic development features of China, learning international practices and experiences and raising the orientation of environmental damage assessment have great meaning in exploring the suitable environmental damage assessment system. PMID:23914513

Zhang, Hong-zhen; Cao, Dong; Yu, Fang; Wang, Jin-nan; Qi, Ji; Jia, Qian; Zhang, Tian-zhu; Luo, Yong-ming

2013-05-01

423

The constitutive representation of high-temperature creep damage  

NASA Technical Reports Server (NTRS)

The elastic-viscoplastic constitutive equations of Bodner-Partom were applied to modeling creep damage in a high temperature Ni-alloy, B1900 + Hf. Both tertiary creep in bulk materials and creep crack growth in flawed materials were considered. In the latter case, the energy rate line integral was used for characterizing the crack driving force, and the rate of crack extension was computed using a local damage formulation that assumed fracture was controlled by cavitation occurring within the crack-tip process zone. The results of this investigation were used to assess the evolution equation for isotropic damage utilized in the Bodner-Partom constitutive equations.

Chan, K. S.

1988-01-01

424

Infrared thermography of damage evaluation in leather products  

NASA Astrophysics Data System (ADS)

The paper aims to illustrate three advantages of infrared thermography as a non-destructive, non-contact and real-time technique (a) to observe the progressive damage processes and failure mechanisms of leather, (b) to detect the occurrence of intrinsic dissipation localization, and (b) to evaluate a threshold of acceptable damage. The parameter, investigated in this paper, is the heat generation due to intrinsic dissipation caused by anelasticity and/or inelasticity of leather. It readily describes the damage location and the failure evolution of leather for sport foot-wear.

Luong, Minh Phong

1999-05-01

425

Experimental Series on Behavior of Post-Damage Recollected Material  

NASA Astrophysics Data System (ADS)

Spallation damage, a typical method of failure for ductile materials, results from the nucleation, growth and coalescence of voids caused by high tensile stress. Specific areas of research on spallation damage include the damage initiation regime in convergent geometry, behavior of material recollected after damage, and effects of convergent geometry (shear stresses, etc.) on the material response. Currently, models of spallation phenomena are typically based on experiments using a planar configuration, where a significant body of data exists from gas gun, laser and high-explosive experiments. Planar experiments allow for one-dimensional analysis of the evolution of failure characteristics. Using a cylindrical configuration to study spallation damage, however, requires the consideration of physical effects not present in the planar configuration. Cylindrical experiments allow for a careful analysis of the effect of convergence and two-dimensional strains and shear stresses on the spallation profile of a material. These experiments challenge existing computational material models and databases and provide motivation to improve these models and increase the predictive capabilities of codes. A series of experiments (R-Damage-0, -1 and -2) previously provided data about failure initiation of a well-characterized material (aluminum) in a cylindrical geometry. This presentation will cover the theory, design and results for the next series of experiments (R-Damage-3, -4 and -5), which studied the behavior of material recollected after damage from pressures in the damage initiation regime.

Kaul, Ann; Rodriquez, George

2007-06-01

426

Law GLOBAL PERSPECTIVE EXPERIENTIAL LEARNING  

E-print Network

FACULTY OF Law· GLOBAL PERSPECTIVE · EXPERIENTIAL LEARNING · INTERDISCIPLINARY OPPORTUNITIES OKOK 44112020 VIEWBOVIEWBO #12;WELCOME TO QUEEN'S LAW Queen's Faculty of Law is renowned for its unique setting in downtown Kingston. Most of our students live close to campus and the law school hums

Abolmaesumi, Purang

427

FACTS ABOUT ADMISSION TO LAW  

E-print Network

FACTS ABOUT ADMISSION TO LAW Law FACULTY OF · GLOBAL PERSPECTIVE · EXPERIENTIAL LEARNING · INTERDISCIPLINARY OPPORTUNITIES #12;FACTS ABOUT ADMISSION TO LAW SCHOOL WHAT POST SECONDARY EDUCATION DO I NEED TO APPLY? Queen's Faculty of Law offers the Juris Doctor (J.D.) degree. The J.D. is the credential

Graham, Nick

428

On the effect of undercutting on calving rate using continuum damage mechanics.  

NASA Astrophysics Data System (ADS)

Several studies have shown that mechanical ice loss through calving is responsible for most of ice discharge from glaciers and ice sheets. However calving processes are complex and still poorly understood. Representation of calving into ice flow models is still limited and the estimation of future ice loss of Greenland and Antarctic ice sheets is therefore inaccurate: state-of-the-art in calving modelling is the result of strong approximations or empirically-based laws. Calving is the main mechanism controlling the position of the terminus, but melting at the front below the waterline can be seen as a second order process modulating the calving rate. Observations have shown that variation of frontal melting exists in Greenland as well as in Antarctica, and is an important factor in explaining the maximal advance and the short term variations of the glacier front. Here, we used a continuum damage mechanics (CDM) framework to investigate the response of a glacier terminus to submarine perturbation. This CMD model is implemented into the Elmer/Ice full-Stokes ice-flow model. This work is initiated in a two-dimensional flowline approach. The damage evolves depending on the stress field in the ice and propagates through the media thanks to an advection equation. As a consequence, the viscosity of the ice is modified via a change of an enhancement factor. In our simulation, an initial grounded-terminated glacier is perturbed by an increase in subaqueous melting. Melting of subaqueous part of the glacier front results in the development of a bloc of ice overhanging the waterline, leading to the calving of the aerial part: this phenomenon is called undercutting. The upper surface of the glacier and the vertical front are defined as free surfaces. Sensitivity in terms of stress and damage fields evolutions through time are investigated in response to the various melting perturbations. Implications on calving rate are discussed.

Krug, Jean; Durand, Gal; Weiss, Jrme; Gagliardini, Olivier

2013-04-01

429

Understanding Evolution  

NSDL National Science Digital Library

This site provides access to basic and advanced online resources for teaching the science and history of evolutionary biology. The resources are organized by topic: the mechanisms of evolution; the relevance of evolutionary theory to everyday life; lines of scientific evidence; and the history of ideas, research, and contributors in the study of evolution. For teachers, there are searchable databases of lesson plans, activities, and conceptual frameworks on the history of life, evidence for evolution, mechanisms of evolution, and the nature of science. Other materials include links to news items and highlighted features on specific evolution topics.

2004-02-06

430

Federal Communications Law Journal  

NSDL National Science Digital Library

There's a whole lot of material to cover within the world of communications law, and within their aegis, the Federal Communications Law Journal (FCLJ) covers everything from intellectual property to cable regulation. The Journal is published by Indiana University law students, and it also serves as the official journal for the Federal Communications Bar Association. This status also means that the Journal will occasionally feature pieces by members of Congress and commissioners in the Federal Communications Commission. First-time visitors to the site can browse through the contents of the most recent issues, or they can browse through archived issues all the way back to 1993. Also, visitors can view some of their short commentaries in the "Forum" area and learn about print subscriptions and submitting manuscripts for consideration.

431

Student Press Law Center  

NSDL National Science Digital Library

Created in 1974, the Student Press Law Center (SPLC) is the ânation's only legal assistance agency devoted exclusively to educating high school and college journalists about the rights and responsibilities embodied in the First Amendment.â Based in Arlington, Virginia the Center provides free legal advice and information along with low-cost educational materials. On its homepage, visitors can make their way through sections that include Know Your Rights and Classroom Resources. In Know Your Rights, visitors can learn about the rights of high school journalists and educators, peruse an online law library, and check out an interactive map tracking the latest legal developments in student press rights nationally. Moving on, the Classroom Resources area brings together dozens of classroom handouts, presentations, and some fun short quizzes regarding libel, privacy, and other media-law issues.

432

Newton's Third Law  

NSDL National Science Digital Library

This educational wallsheet illustrating Newton's Third Law of Motion is the third of a set of four. Each image on the front of the poster illustrates Newton's Third Law, and is described on the back. The wallsheet also provides teachers with background information, pre-activity reading for the students that relates the law to the action of the fuel being expelled from the rocket and its reaction on the rocket carrying the Swift satellite into orbit, as well as Swift's turning motions once in orbit, pre-activity discussion with optional questions that relate to the Swift satellite, a classroom-ready activity and assessment, and post-activity discussions that tie the classroom activity back to the Swift satellite.

433

Reducing Radiation Damage  

SciTech Connect

This talk describes the use of a modified treatment sequence, i.e., radiation dose, geometry, dwell time, etc., to mitigate some of the deleterious effects of cancer radiotherapy by utilizing natural cell repair processes. If bad side effects can be reduced, a more aggressive therapy can be put into place. Cells contain many mechanisms that repair damage of various types. If the damage can not be repaired, cells will undergo apoptosis (cell death). Data will be reviewed that support the fact that a small dose of radiation will activate damage repair genes within a cell. Once the mechanisms are fully active, they will efficiently repair the severe damage from a much larger radiation dose. The data ranges from experiments on specific cell cultures using microarray (gene chip) techniques to experiments on complete organisms. The suggested effect and treatment is consistent with the assumption that all radiation is harmful, no matter how small the dose. Nevertheless, the harm can be reduced. These mechanisms need to be further studied and characterized. In particular, their time dependence needs to be understood before the proposed treatment can be optimized. Under certain situations it is also possible that the deleterious effects of chemotherapy can be mitigated and the damage to radiation workers can be reduced.

Blankenbecler, Richard

2006-06-05

434

Diffusion processes satisfying a conservation law constraint  

E-print Network

We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequences of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner's generalized Dirichlet processes.

J. Bakosi; J. R. Ristorcelli

2014-01-13

435

The Publishing Law Center  

NSDL National Science Digital Library

Presented by the Law Office of Lloyd L. Rich in Denver, Colorado, this site is attractively organized and provides useful information for "publishing companies, large and small" as well as anyone concerned with issues of intellectual property. Self-promotion aside, the site provides an up-to-date, online collection of articles dealing with legal issues such as copyrights, trademarks, publishing, corporate development, contracts, and Internet protection; a directory of links to publishing resources; a calendar of upcoming seminars; and subscriptions to a free email newsletter distributing articles on publishing law and the "business of running a profitable publishing company."

436

Analyses of the cell mechanical damage during microinjection.  

PubMed

The microinjection is an essential technique to introduce foreign materials into biological cells. The soft cell is inevitably ruptured by the microinjector during microinjection. We discuss the way to reduce the mechanical damage by analyzing the control parameters during microinjection. The computational model is developed with the dissipative particle dynamics to simulate the soft mechanical properties of biological cells. The cell model contains the membrane networks, the internal cytoskeleton, crosslink proteins, motors and their functions. The weak power law rheology verifies our computational model. The number of ruptured bonds is used to describe the extent of the mechanical damage that the cell experiences during microinjection. Some experiments are conducted on the Zebrafish embryos. Both the simulation works and experimental results show that the size, shape of the microinjector tip, and the injection velocity have a significant influence on the cell damage. A small, sharp microinjector with a high velocity can reduce the mechanical damage. PMID:25584666

Liu, Fei; Wu, Dan; Wu, Xiaoyong; Chen, Ken

2015-02-01

437

The processes controlling damage zone propagation induced by wellbore fluid injection  

NASA Astrophysics Data System (ADS)

Induced seismicity by wellbore fluid injection is an important tool for enhancing permeability in hydrocarbon and geothermal reservoirs. We model nucleation and propagation of damage zones and seismicity patterns for two-dimensional plane strain configuration at a depth of 5 km using novel numerical software developed in the course of this study. Simulations include the coupling of poro-elastic deformation and groundwater flow with damage evolution (weakening and healing) and its effect on the elastic and hydrologic parameters. Results show that the process occurring during fluid injection can be divided into four stages. The duration of each stage depends on the hydrological and mechanical parameters. Initially, fluid flows into the rock with no seismic events (5 to 20 hr). At this stage, damage increases from 0 to 1 creating two sets of conjugate zones (four narrow damage zones). Thereafter, the occurrence of seismic events and faulting begins and accelerates for the next 20 to 70 hr. At the initial part of this stage, two of the damage zones create stress shadows on the other two damage zones that stop progressing. The velocity of the advancing damage is limited only by the rock parameters controlling damage evolution. At the third stage, which lasts for the following 20-30 hr, damage acceleration decreases because fluid transport becomes a limiting factor as the damage zones are too long to efficiently transfer the pressure from the well to the tip of the damage zones. Finally, the damage decelerates and even stops in some cases. The propagation of damage is controlled and limited by fluid transport from the injection well to the tip of the damage zones because fluid transport does not keep up with the dilatancy of the damage zones. The time and distance of propagation depend on the damage-permeability coupling and the remote shear stress. Higher remote shear stress causes shorter initial periods of no seismicity; strong damage-permeability coupling causes longer acceleration stage.

Shalev, Eyal; Lyakhovsky, Vladimir

2013-04-01

438

Law as Economy: Convention, Corporation, Currency  

E-print Network

1015 Law as Economy: Convention, Corporation, Currency Ritu Birla* I. Law as Economy: Nomos. Law Inside/Outside Economy of an orthodox faith in economy as universal law, that is, in the free market as the law of the universe

Barrett, Jeffrey A.

439

Supersymmetry and conservation laws in the KdV system  

SciTech Connect

The role of supersymmetry in the KdV-MKdV hierarchy of conservation laws is examined. Among all the fifth order evolution equations, the Lax equation turns out to be the only one which is mapped into its modified partner through the pair of supersymmetric transformations.

Roy, P.K. (Dept. of Physics, Haldia Government College, P.O. Debhog, Midnapore 721 657, West Bengal (IN)); Lahiri, A. (Dept. of Physics, Surendranath College, Calcutta 700 009, West Bengal (IN)); Bagchi, B. (Dept. of Applied Mathematics, Vidyasagar Univ., Midnapore 721 101, West Bengal (IN))

1990-07-20

440

Long simulations of the Solar System: Brouwer's Law and Chaos  

E-print Network

Long simulations of the Solar System: Brouwer's Law and Chaos K. R. Grazier W. I. Newman James M of motion for self- gravitating systems, particularly in the context of our Solar System's evolution growth can be attained in 3-D Solar System integrations. Our integrations are such that the positions

Sharp, Philip

441

Phenylbutazone and chromosomal damage.  

PubMed Central

Investigation of 44 paired test and control patients, all suffering from rheumatoid arthritis, following exposure to phenylbutazone (PBZ) and/or oxyphenbutazone (OPB), suggests that there is no significant increase in the level of chromosomal damage in lymphocytes. The control subjects comprised two series, one previously exposed to PBZ and/or OPB, but not for at least 1-5 years, and the other never exposed to PBZ or OPB. No significant difference in the level of chromosome damage was found between patients never exposed, previously exposed, or now receiving PBZ and/or OPB. PMID:769706

Walker, S; Price Evans, A; Benn, P A; Littler, T R; Halliday, L D

1975-01-01

442

The Evolution of Complex Life  

NASA Technical Reports Server (NTRS)

In considering the probabilities that intelligent life might exist elsewhere in the Universe, it is important to ask questions about the factors governing the emergence of complex living organisms in the context of evolutionary biology, planetary environments and events in space. Two important problems arise. First, what can be learned about the general laws governing the evolution of complex life anywhere in space by studying its history on the Earth? Second, how is the evolution of complex life affected by events in space? To address these problems, a series of Science Workshops on the Evolution of Complex Life was held at the Ames Research Center. Included in this paper are highlights of those workshops, with particular emphasis on the first question, namely the evolution of complex extraterrestrial life.

Billingham, John

1989-01-01

443

The Role of Damage Cascade in the Nanocrystallization of Metallic Glass  

E-print Network

The multi-scale modeling of ion-solid interactions presented can lead to a fundamentally new approach for understanding temperature evolution and damage formation. A coupling of the Monte Carlo code, SRIM, to a C FEM heat transfer code...

Myers, Michael T.

2011-08-08

444

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

E-print Network

THRESHOLD-BASED QUASI-STATIC BRITTLE DAMAGE EVOLUTION ADRIANA GARRONI AND CHRISTOPHER J. LARSEN GARRONI AND CHRISTOPHER J. LARSEN weak form of the threshold formulation suggests the correct relaxation

Garroni, Adriana

445

Damage characterization in concrete using diffuse ultrasound  

NASA Astrophysics Data System (ADS)

Diffuse ultrasonic measurements were used to characterize the state of stress-induced damage (volumetric microcracking) in concrete specimens. The test specimens were subjected to cycles of stepwise uniaxial compression. At each step, the loading (stress- or strain-controlled) was held constant and a series of ultrasonic measurements parallel and perpendicular to the loading were obtained. Unusually long signals were recorded, so that the diffuse ultrasonic regime tailing the coherent field could be studied. In the diffuse regime, the measured ultrasonic response is a superposition of reflections from scatters within concrete and thus, very sensitive to the changes in concrete microstructure. Using Coda Wave Interferometry (CWI), the evolution of diffuse velocity with the increasing load was monitored. The rate of change in the diffusion velocities was shown to be a good indication of the state of (low to medium intensity) damage in concrete.

Shokouhi, Parisa; Niederleithinger, Ernst

2012-05-01

446

Athletics and the Law.  

ERIC Educational Resources Information Center

This book answers questions concerning athletics and the law. The chapters include trends in litigation, disruptive behavior, the changing attitude of the court toward married athletes, training rules, and good conduct codes. They include the problem of athletic travel, the changing role of state athletic associations with their diverse rules,

Appenzeller, Herb

447

Demonstrating Newton's Second Law.  

ERIC Educational Resources Information Center

Describes an apparatus for demonstrating the second law of motion. Provides sample data and discusses the merits of this method over traditional methods of supplying a constant force. The method produces empirical best-fit lines which convincingly demonstrate that for a fixed mass, acceleration is proportional to force. (DDR)

Fricker, H. S.

1994-01-01

448

A natural law  

Microsoft Academic Search

With credible assumptions, a general law is developed which appears to encompass all distributions arising from processes involving independent events. A number of familiar distributions may be obtained therefrom as well as many unusual distributions. The results suggest new methods for the analysis of experimental data and observations.

W. J. McBride

1968-01-01

449

Relativistic Kepler's third law  

Microsoft Academic Search

The authors give a post-Newtonian generalization of Kepler's third law that includes spin and quadrupole moment effects, parameterized post-Newtonian parameters gamma and beta, and the Nordtvedt effect. The time from periastron to apastron is also found, and it turns out, in general, not to be equal to half the period. The results are given in a very general coordinate system

B. M. Barker; G. G. Byrd; R. F. Oconnell

1986-01-01

450

Kepler's third law  

Microsoft Academic Search

There are slight differences in the standards of Kepler's third law in the different textbooks. The authors work out an average r, that over the arc lengths of the orbit and show that such an average is equal to the semimajor axis.(AIP)

A. Tan; W. L. Chameides

1981-01-01

451

Team Teaching School Law  

ERIC Educational Resources Information Center

Graduate students preparing themselves for a career in school administration are typically apprehensive about the legal issues they will face in their first administrative position. After teaching school law for the first time, the author believed that there had to be a more effective way to reach these students rather than the traditional methods

Vanko, John G.; Rogina, Raymond P.

2005-01-01

452

Stoke's Law Problem Set  

NSDL National Science Digital Library

This is a problem set that involves the calculation of velocities from a Reynolds number, determination of Stoke's Law applicability, and calculation of settling velocities for a variety of grain sizes and materials. This can be used in conjunction with a lab but is itself just a problem set.

Rachel Headley

453

Law, endowments, and finance  

Microsoft Academic Search

Using a sample of 70 former colonies, this paper assesses two theories regarding the historical determinants of financial development. The law and finance theory holds that legal traditions, brought by colonizers, differ in terms of protecting the rights of private investors vis--vis the state, with important implications for financial markets. The endowment theory argues that the disease environment encountered by

Thorsten Beck; Asli Demirg-Kunt; Ross Levine

2003-01-01

454

Law, Endowment, and Finance  

Microsoft Academic Search

This paper assesses two theories regarding the historical determinants of international differences in financial development. The law and finance theory holds that legal traditions differ in terms of the priority they attach to protecting the rights of private investors vis-a-vis the State and this has important implications for financial development. The endowment theory argues that the disease and geographical environment

Thorsten Beck; Asli Demirguc-Kunt; Ross Levine

2002-01-01

455

Law as Focus.  

ERIC Educational Resources Information Center

Shows how teachers can increase students' general appreciation of literature and improve students' writing skills by studying literature with legal issues and images of the law. Cites several examples of such literature, including Geoffrey Chaucer's "Canterbury Tales," William Shakespeare's "Measure for Measure," and Jonathan Swift's "Gulliver's

Blythe, Joan Heiges

1989-01-01

456

Education Law. Second Edition.  

ERIC Educational Resources Information Center

This second edition of this reference guide provides a survey of some of the major legal problems that confront policymakers and school administrators. It contains landmark cases and other cases that best illustrate major principles of education law, along with summaries, discussions, and analyses of the cases. Edited cases are integrated into

Imber, Michael; van Geel, Tyll

457

THE INVERSE CARE LAW  

Microsoft Academic Search

care tends to vary inversely with the need for it in the population served. This inverse care law operates more completely where medical care is most exposed to market forces, and less so where such exposure is reduced. The market distribution of medical care is a primitive and historically outdated social form, and any return to it would further exag-

JULIAN TUDOR HART

458

WILLIAMS COLLEGE COLLEGE LAWS  

E-print Network

1 WILLIAMS COLLEGE COLLEGE LAWS ADOPTED BY THE PRESIDENT AND TRUSTEES OF WILLIAMS COLLEGE ON APRIL, the government and direction of Williams College are vested in the President and Trustees. 2. Number of Trustees. The number of the Trustees, including the President of the College, shall be fixed from time to time

Aalberts, Daniel P.

459

WILLIAMS COLLEGE COLLEGE LAWS  

E-print Network

1 WILLIAMS COLLEGE COLLEGE LAWS ADOPTED BY THE PRESIDENT AND TRUSTEES OF WILLIAMS COLLEGE ON APRIL and direction of Williams College are vested in the President and Trustees. 2. Number of Trustees. The number of the Trustees, including the President of the College, shall be fixed from time to time by the Trustees

Cox, Rónadh

460

WILLIAMS COLLEGE COLLEGE LAWS  

E-print Network

1 WILLIAMS COLLEGE COLLEGE LAWS ADOPTED BY THE PRESIDENT AND TRUSTEES OF WILLIAMS COLLEGE ON APRIL. In accordance with the provisions of the charter, the government and direction of Williams College are vested of the College, shall be fixed from time to time by the Trustees and shall not be more than twenty-five or less

Aalberts, Daniel P.

461

WILLIAMS COLLEGE COLLEGE LAWS  

E-print Network

WILLIAMS COLLEGE COLLEGE LAWS ADOPTED BY THE PRESIDENT AND TRUSTEES OF WILLIAMS COLLEGE ON APRIL 12 with the provisions of the charter, the government and direction of Williams College are vested in the President and Trustees. 2. Number of Trustees. The number of the Trustees, including the President of the College, shall

Aalberts, Daniel P.

462

On Proebsting's Law  

Microsoft Academic Search

In 1965 Gordon Moore observed that the capacity of semiconductor ICs doubled every 18 to 24 months. This trend, now known as Moore's Law, has held for over 25 years and is responsible for the exponential increase in microprocesso r performance over this period. In 1998 Todd Proebsting made a similar-in-spirit, but altogether less optimistic observation about optimizing compilers. His

Kevin Scott

463

Assistive Technology Laws  

MedlinePLUS

Understanding the Law & Assistive Technology There is a wide range of assistive technology (AT) services and devices to which a child may be entitled. It ... hotels, doctors offices, etc. Title IV addresses assistive technology specifically, as it requires that telephone companies provide ...

464

Torsion and conservation laws  

Microsoft Academic Search

The interaction of spinor and electromagnetic fields with the torsion of space-time is studied within the framework of the Einstein-Cartan theory. The equivalent nonlinear theory in Riemann space is obtained. The conservation laws for the vector and pseudovector currents are investigated in the nonlinear theory.

E. V. Smetanin; E. Ostgaard; V. Canute; L. D. Landau; R. L. Bowers; E. P. T. Liang; H. Heintzmann; W. Hillebrandt; V. Ureche; S. Weinberg; B. Zel; I. M. Lifshits

1986-01-01

465

School Law Update, 1985.  

ERIC Educational Resources Information Center

A wide variety of contemporary legal issues, involving all levels of public and private education, are addressed in the 20 papers in this volume. Written in law review style and including legal citations, the papers and authors included are: (1) "Who Runs the Schools" (Flygare); (2) "Copyright Issues in Computer-Assisted Instruction" (Helm); (3)

Jones, Thomas N., Ed.; Semler, Darel P., Ed.

466

Desegregation Law; An Introduction.  

ERIC Educational Resources Information Center

This booklet is comprised of the following: (i) School desegregation law: recent developments (by J. Harold Flannery), dealing with several threshold questions such as: What is illegal school segregation? What must be done about it and by whom? What will be the role of the courts after desegregation? (ii) School desegregation--the past five years,

Integrated Education Associates, Evanston, IL.

467

Laws of programming  

Microsoft Academic Search

A complete set of algebraic laws is given for Dijkstra's nondeterministic sequential programming language. Iteration and recursion are explained in terms of Scott's domain theory as fixed points of continuous functionals. A calculus analogous to weakest preconditions is suggested as an aid to deriving programs from their specifications.

C. A. R. Hoare; Ian J. Hayes; He Jifeng; Carroll Morgan; A. W. Roscoe; Jeff W. Sanders; I. H. Sorensen; J. Michael Spivey; Bernard Sufrin

1987-01-01

468

On the psychophysical law  

Microsoft Academic Search

The general psychophysical law is that equal stimulus ratios produce equal subjective ratios. A first-order approximation is a power function whose exponent varies from 0.3 (loudness) to 2.0 (visual flash rate). This holds for Class I (prothetic) or quantitative continua, distinguishable by 4 criteria: \\

S. S. Stevens

1957-01-01

469

Faraday's law paradoxes  

Microsoft Academic Search

Some unusual circuits have been devised which appear to produce a flux change without generating a corresponding induced potential difference, thus violating Faraday's law. What has been generated is a large amount of controversy and this article shows the cause of the dispute and its resolution.

A. Nussbaum

1972-01-01

470

Equal Justice Under Law.  

ERIC Educational Resources Information Center

This special theme issue of "Update on Law-Related Education""tells about the past, present, and future of equal legal representation for all in our society." It is dedicated to the history and heroes of legal aid for the poor and the need to further that cause if the United States hopes to achieve equal justice for all. In his foreword, Justice

Johnson, Earl, Jr., Ed.

1994-01-01

471

Lectures on Law Enforcement.  

ERIC Educational Resources Information Center

Three lectures on law enforcement are presented that were prepared for study purposes at Johnson County Community College. The first lecture examines the fundamental ideas of the Age of Enlightenment and discusses their influence on the American Revolution, the United States Constitution, and the Bill of Rights. Major provisions of the Bill of

Nettleship, Lois

472

Algorithms for coupled problems that preserve symmetries and the laws of thermodynamics  

E-print Network

Algorithms for coupled problems that preserve symmetries and the laws of thermodynamics Part I is that they rigorously preserve the two laws of thermodynamics as well as the symmetries of the systems they model-equilibrium thermodynamics and we follow a systematic methodology that results in discrete evolution equations which mimic

Romero, Ignacio

473

Eye for an Eye, A Survey History of Law, Social Studies: 6448.06.  

ERIC Educational Resources Information Center

This guide is one of a series in the Quinmester Program to aid high school teachers in planning instructional programs concerning the origins and evolution of our system of law. The purpose of this course of study is to help students understand the rights and responsibilities of citizens under the law; to motivate them to make judgments upon the

Henderson, Jerry W.

474

Advantage of a predictive control law for extreme adaptive optics imaging  

Microsoft Academic Search

We study the application of a predictive control law based on a Kalman filter for an extreme adaptive optics system. In particular, we discuss the minimization of temporal error and show the evolution of prediction errors with the order of the model. We also discuss the choice of the optimal temporal frequency as a function of the control law and

B. Le Roux; M. Carbillet

2006-01-01

475

Numerical modeling of mountain building: Interplay between erosion law and crustal rheology  

E-print Network

Numerical modeling of mountain building: Interplay between erosion law and crustal rheology V. Cattin, and J. Lave´ (2004), Numerical modeling of mountain building: Interplay between erosion law and the evolution of mountain belts. Few 3D simulations with full coupling between tectonics and erosion have been

Demouchy, Sylvie

476

Frictional response of a thick gouge sample: 2. Friction law and implications for faults  

E-print Network

not involve any characteristic length scale. The decrease of the gouge friction coefficient m with imposed of the friction law is to prescribe the evolution of the fault effective coefficient of friction as a function-weakening laws prescribe that the coefficient of friction essentially depends on slip displacement [e.g., Palmer

Schmittbuhl, Jean

477

Damage analysis and fundamental studies for fusion reactor materials development  

Microsoft Academic Search

The philosophy of the program at the University of California Santa Barbara has been to develop a fundamental understanding of both the basic damage processes and microstructural evolution that take place in a material during neutron irradiation and the consequent dimensional and mechanical property changes. This fundamental understanding can be used in conjunction with empirical data obtained from a variety

G. R. Odette; G. E. Lucas

1991-01-01

478

Clarifying Baker's Law  

PubMed Central

Background Baker's Law states that colonization by self-compatible organisms is more likely to be successful than colonization by self-incompatible organisms because of the ability for self-compatible organisms to produce offspring without pollination agents. This simple model has proved very successful in plant ecology and has been applied to various contexts, including colonizing or ruderal species, islands colonizers, invasive species or mating system variation across distribution ranges. Moreover, it is one of the only models in population biology linking two traits of major importance in ecology, namely dispersal and mating system. Although Baker's Law has stimulated a large number of empirical studies reporting the association of self-fertilization and colonizing ability in various contexts, the data have not established a general pattern for the association of traits. Scope In this paper, a critical position is adopted to discuss and clarify Baker's Law. From the literature referring to Baker's Law, an analysis made regarding how mating success is considered in such studies and discrepancies with population genetics theory of mating systems are highlighted. The data reporting the association of self-fertilization and colonizing ability are also briefly reviewed and the potential bias in interpretation is discussed. Lastly, a recent theoretical model analysing the link between colonizing ability and self-fertilization is considered. Conclusions Evolutionary predictions are actually more complex than Baker's intuitive arguments. It appears that Baker's Law encompasses a variety of ecological scenarios, which cannot be considered a priori as equivalent. Questioning what has been considered as self-evident for more than 50 years seems a reasonable objective to analyse in-depth dispersal and mating system traits. PMID:21685434

Cheptou, P.-O.

2012-01-01

479

Component damage analysis  

NASA Technical Reports Server (NTRS)

Semiconductor breakdown in aircraft was investigated since lightning strikes induce large current and voltage pulses which may cause failure. Work was done to determine whether or not these voltages and currents cause upset or damage to active or passive components. Failure thresholds were studied extensively and an assessment was made of the vulnerability of a system to a transient environment.

1977-01-01

480

Modifying Radiation Damage  

PubMed Central

Radiation leaves a fairly characteristic footprint in biological materials, but this is rapidly all but obliterated by the canonical biological responses to the radiation damage. The innate immune recognition systems that sense danger through direct radiation damage and through associated collateral damage set in motion a chain of events that, in a tissue compromised by radiation, often unwittingly result in oscillating waves of molecular and cellular responses as tissues attempt to heal. Understanding natures whispers that inform on these processes will lead to novel forms of intervention targeted more precisely towards modifying them in an appropriate and timely fashion so as to improve the healing process and prevent or mitigate the development of acute and late effects of normal tissue radiation damage, whether it be accidental, as a result of a terrorist incident, or of therapeutic treatment of cancer. Here we attempt to discuss some of the non-free radical scavenging mechanisms that modify radiation responses and comment on where we see them within a conceptual framework of an evolving radiation-induced lesion. PMID:20583981

Kim, Kwanghee; McBride, William H.

2011-01-01

481

Coping with brain damage  

NASA Technical Reports Server (NTRS)

Two neurological disorders, cerebral palsy, and traumatic brain damage as from an accident, are considered. The discussion covers the incidence of disabilities, their characteristics, and what is now being done to deal with them, particularly in reference to areas in which the capabilities of the engineer can be effectively applied.

Waring, W.

1974-01-01

482

Damaged Hospital Wing  

USGS Multimedia Gallery

This two story hospital wing in Cauquenes, Chile suffered severe damage to the wall of the first floor as a result of the M 8.8 earthquake on Feb. 27, 2010. This building must be torn down. All patients were successfully evacuated at 3:34 AM after the earthquake shaking started....

483

Superlattice Photocathode Damage Analysis  

NASA Astrophysics Data System (ADS)

Jefferson Lab uses 100 kV DC high voltage photoguns with high polarization strained superlattice GaAs photocathodes to achieve electron beam polarization over 80%. The photocathode is subjected to back-bombardment from ionized residual gasses during operation. We present surface analyses using transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) to characterize photocathode damage.

Stutzman, Marcy L.; Grames, Joseph

2009-08-01

484

Comparative investigation of damage performance on K9 and SiO2 under 1064-nm nanosecond laser irradiation  

NASA Astrophysics Data System (ADS)

Laser damage performance of K9 glass and fused silica glass were tested respectively at same experimental condition with 1064 nm nanosecond laser. The initial damage threshold (IDT), the damage growth threshold (DGT) and the damage growth laws of the two optics glass were investigated comparatively. The results show that the damage growth behavior of the two glasses are quite different, for example, the lower damage growth threshold and the higher damage growth coefficient for K9 glass, which can attribute to the difference of the material's damage morphology, optical absorption, residual stress near damage site between the two optics glass. The research is very important to choose transparent optical material applied in high power laser.

Liu, Hongjie; Wang, Fengrui; Zhang, Zhen; Huang, Jin; Zhou, Xinda; Jiang, Xiaodong; Wu, Weidong; Zheng, Wanguo

2011-11-01

485

Comparative investigation of damage performance on K9 and SiO2 under 1064-nm nanosecond laser irradiation  

NASA Astrophysics Data System (ADS)

Laser damage performance of K9 glass and fused silica glass were tested respectively at same experimental condition with 1064 nm nanosecond laser. The initial damage threshold (IDT), the damage growth threshold (DGT) and the damage growth laws of the two optics glass were investigated comparatively. The results show that the damage growth behavior of the two glasses are quite different, for example, the lower damage growth threshold and the higher damage growth coefficient for K9 glass, which can attribute to the difference of the material's damage morphology, optical absorption, residual stress near damage site between the two optics glass. The research is very important to choose transparent optical material applied in high power laser.

Liu, Hongjie; Wang, Fengrui; Zhang, Zhen; Huang, Jin; Zhou, Xinda; Jiang, Xiaodong; Wu, Weidong; Zheng, Wanguo

2012-01-01

486

BERKELEY LAW CERTIFICATE IN ENVIRONMENTAL LAW Berkeley Law students have the option of earning a Certification of Specialization in  

E-print Network

paper focusing on some aspect of environmental, land use or natural resource law. The paper requirement Pollution) (3 units) LAW 273.63 Public Lands and Natural Resources Law (3 units) LAW 273.71 California1 BERKELEY LAW CERTIFICATE IN ENVIRONMENTAL LAW 2010-2011 Berkeley Law students have the option

Kammen, Daniel M.

487

Numerical study of damage in unsaturated Geological and Engineered barriers  

NASA Astrophysics Data System (ADS)

The theoretical framework of a damage model dedicated to non-isothermal unsaturated porous media is presented. The damage variable is a second-order tensor, and the model is formulated in independent state variables. The behavior laws are derived from a postulated expression of Helmholtz free energy. The damaged rigidities are computed by applying the Principle of Equivalent Elastic Energy (PEEE). Internal length parameters are introduced in the expressions of liquid water and vapor conductivities, to account for cracking effects on fluid flows. The damage model has been implemented in ?-Stock Finite Element program. The mechanical aspect of the damage model is validated by simulating a triaxial compression test on a dry isothermal brittle material. Then, a sophisticated model of nuclear waste disposal, involving two non-isothermal unsaturated porous media, is reproduced. The results obtained in elasticity are in good agreement with the results presented in the corresponding reference article. A parametric study on initial damage is then performed to assess the influence of the Excavated Damaged Zone (EDZ) on the response of the nuclear waste repository during the heating phase. The trends meet the theoretical expectations.

Arson, C.; Gatmiri, B.

488

Characteristics of 355 nm Laser Damage in Bulk Materials  

NASA Astrophysics Data System (ADS)

The laser damage resistances of four crystals (CaF2, MgF2, Al2O3, and SiO2) and fused silica (JGS1) irradiated at 355 nm (8 ns, 300-on-1) are reported. The laser-induced damage threshold is measured using a tripled Nd:YAG laser system. The results obtained from the pure crystals are in accordance with their specific optical, mechanical, and thermal properties. An empirical law based on the FranzKeldysh effect can interpret the experimental results.

Yu, Zhen-Kun; He, Hong-Bo; Qi, Hong-Ji; Fang, Zhou; Li, Da-Wei

2013-06-01

489

A viscoelastic damage model for polycrystalline ice, inspired by Weibull-distributed fiber bundle models. Part I: Constitutive models  

NASA Astrophysics Data System (ADS)

We consider a constitutive model for polycrystalline ice, which contains delayed-elastic and viscous deformations, and a damage variable. The damage variable is coupled to the delayed-elastic deformation by a fiber bundle ansatz. We construct an isotropic theory, which can be calibrated with experimental data. Furthermore, we generalize the theory to a damage model in terms of rank-four tensors. This general model allows the evolution of anisotropic damage.

Keller, Arne; Hutter, Kolumban

2014-04-01

490

Thermodynamics of microstructure evolution: grain growth Victor L. Berdichevsky  

E-print Network

Thermodynamics of microstructure evolution: grain growth Victor L. Berdichevsky Mechanical thermodynamic parameters, entropy of microstructure and temperature of microstruc- ture. It was claimed that there is "one more law of thermodynamics": entropy of microstructure must decay in isolated thermodynamic stable

Berdichevsky, Victor

491

An Evolutionary Approach to Damage Recovery of robot Motion with Muscles  

Microsoft Academic Search

Robots that can recover from damage did not exist outside science fiction. Here we describe a self-adaptive snake robot that uses shape memory alloy as muscles and an evolutionary algorithm as a method of adaptive control. Experiments demonstrate that if some of the robot's muscles are deliberately damaged, evolution is able to find new sequences of muscle activations that compensate,

Siavash Haroun Mahdavi; Peter J. Bentley

2003-01-01

492

Finite element approach for modelling fatigue damage in fibre-reinforced composite materials  

Microsoft Academic Search

Today, a lot of research is dedicated to the fatigue behaviour of fibre-reinforced composite materials due to their increasing use in all sorts of applications. These materials have a quite good rating as regards to lifetime in fatigue, but the same does not apply to the number of cycles to initial damage, or to the evolution of damage. Composite materials

W. Van Paepegem; J. Degrieck; P. De Baets

2001-01-01

493

Prediction of Damage in Randomly Oriented Short-Fibre Composites by means of A Mechanistic Approach  

SciTech Connect

A micro-macro mechanistic approach to damage in short-fiber composites is developed in this paper. At the micro-scale, the damage mechanisms such as matrix cracking, fiber/matrix debonding are analyzed to define the associated damage variables. The stiffness reduction law dependent on these variables is then established using micromechanical models and average orientation distributions of fibers and microcracks. The macroscopic response is obtained by means of thermodynamics of continuous media, continuum damage mechanics and a finite element formulation.

Nguyen, Ba Nghiep; Khaleel, Mohammad A.

2004-05-01

494

Punctuated equilibrium and power law in economic dynamics  

NASA Astrophysics Data System (ADS)

This work is primarily based on a recently proposed toy model by Thurner etal. (2010) [3] on Schumpeterian economic dynamics (inspired by the idea of economist Joseph Schumpeter [9]). Interestingly, punctuated equilibrium has been shown to emerge from the dynamics. The punctuated equilibrium and Power law are known to be associated with similar kinds of biologically relevant evolutionary models proposed in the past. The occurrence of the Power law is a signature of Self-Organised Criticality (SOC). In our view, power laws can be obtained by controlling the dynamics through incorporating the idea of feedback into the algorithm in some way. The so-called 'feedback' was achieved by introducing the idea of fitness and selection processes in the biological evolutionary models. Therefore, we examine the possible emergence of a power law by invoking the concepts of 'fitness' and 'selection' in the present model of economic evolution.

Gupta, Abhijit Kar

2012-02-01

495

UNDERGRADUATE law.uts.edu.au  

E-print Network

UTS:LAW UNDERGRADUATE COURSES GUIDE 2014 law.uts.edu.au THINK.CHANGE.DO #12;CONTACT US Tel: 1300 ASK UTS (1300 275 887) Ask a Question Online: ask.uts.edu.au law.uts.edu.au Why UTS Law? 01 Facilities and Services 02 Practical Experience at UTS: Law 04 Careers in Law 05 COURSE INFORMATION 06 Bachelor of Laws

University of Technology, Sydney

496

ChemTeacher: Dalton's Law  

NSDL National Science Digital Library

ChemTeacher compiles background information, videos, articles, demonstrations, worksheets and activities for high school teachers to use in their classrooms. The Dalton's Law page includes resources for teaching students about the history and applications of Dalton's Law.

2011-01-01

497