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1

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

2

Evolution of the Second Law of Thermodynamics  

ERIC Educational Resources Information Center

Presents the history surrounding the evolution of the second law of thermodynamics. Discusses Sadi Carnot's contributions, but also refers to those by Clapeyron, Thomson, Joule, Clausius, and Boltzman among others. (RR)

Raman, V. V.

1970-01-01

3

Damage Evolution in Composites with a Homogenization-based Continuum  

E-print Network

Damage Evolution in Composites with a Homogenization-based Continuum Damage Mechanics Model JAYESH homogenization-based continuum damage mechanics (HCDM) model for fiber reinforced composites undergoing micro- mechanical damage. Micromechanical damage in the representative volume element (RVE) is explicitly

Ghosh, Somnath

4

Fatigue damage evolution in uni-directional metal matrix composites using a micro-mechanical damage model  

SciTech Connect

In recent years Metal Matrix Composites (MMC) have drawn wide attention as candidate materials for high temperature applications needed in aerospace and aeronautic industries. Especially the Titanium Matrix Composites (TMC) have been favored for such applications mainly due to their high strength to weight ratio and their ability to maintain their structural integrity even at elevated temperatures. Despite the increased use of these TMC`s for the last decade there is still a need for appropriate material models able to simulate the material behavior of such advanced MMC`s under severe loading conditions such as fatigue loading. Modeling fatigue behavior of MMC`s requires the prediction of material degradation during the material lifetime through the concept of damage and damage evolution. A micro-mechanical fatigue damage model is proposed here capable of modeling damage evolution at the constituent level. Damage criteria are defined for each individual constituent and appropriate damage evolution laws are derived. Furthermore damage evolution in the interface region is considered separately. The overall composite damage is obtained through the employment of a homogenization procedure such as the Mori-Tanaka averaging scheme. Numerical results are shown for high cycle fatigue with respect to a variation in various material and damage model parameters. Furthermore the damage evolution in the fiber, the matrix and the overall composite is presented for a complete fatigue simulation.

Echle, R.; Voyiadjis, G.Z. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Civil and Environmental Engineering

1997-07-01

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

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

7

A two-dimensional micromechanical model of anisotropic elastic-microplastic damage evolution  

Microsoft Academic Search

A two-dimensional micromechanically based model of anisotropic elastic-microplastic damage evolution is presented. The deterioration of the material is represented by equally oriented Dugdale microcracks. Assuming a physically plausible crack growth law a consequent homogenization gives the macroscopic nonlinear stress-strain behavior during a loading process as well as the evolution of the corresponding anisotropic damage and typical characteristics during a final

W. Becker; D. Gross

1988-01-01

8

A one-dimensional micromechanical model of elastic-microplastic damage evolution  

Microsoft Academic Search

Summary A one-dimensional micromechanically based model of elastic-microductile damage evolution is presented. The deterioration of the material is represented by Dugdale micro-cracks. Postulating a physically plausible crack growth law a consequent homogenisation predicts the macroscopic hardening and softening behavior during a loading process as well as the corresponding continuous damage evolution and typical characteristics during a final unloading process.

W. Becker; D. Gross

1987-01-01

9

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

10

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2013 CFR

...Established principles of general maritime law will apply to injury or death...federal case law. Where general maritime law provides no guidance, the general...Maritime Claims Settlement Act. Maritime law applies. (e) Damages not...

2013-07-01

11

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2010 CFR

...Established principles of general maritime law will apply to injury or death...federal case law. Where general maritime law provides no guidance, the general...Maritime Claims Settlement Act. Maritime law applies. (e) Damages not...

2010-07-01

12

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2011 CFR

...Established principles of general maritime law will apply to injury or death...federal case law. Where general maritime law provides no guidance, the general...Maritime Claims Settlement Act. Maritime law applies. (e) Damages not...

2011-07-01

13

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2012 CFR

...Established principles of general maritime law will apply to injury or death...federal case law. Where general maritime law provides no guidance, the general...Maritime Claims Settlement Act. Maritime law applies. (e) Damages not...

2012-07-01

14

32 CFR 536.50 - Determination of damages-applicable law.  

Code of Federal Regulations, 2014 CFR

...Established principles of general maritime law will apply to injury or death...federal case law. Where general maritime law provides no guidance, the general...Maritime Claims Settlement Act. Maritime law applies. (e) Damages not...

2014-07-01

15

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

Microsoft Academic Search

Motivated by mechanical analysis of bones and bone-implant systems, a 3D constitutive law describing the macroscopic mechanical\\u000a behaviour of both cortical and trabecular bone in cyclic (not fatigue) overloads is developed. The proposed model which mathematical\\u000a formulation is established within the framework of generalized standard materials accounts for three distinct material evolution\\u000a modes where elastic, plastic and damage aspects are

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

2009-01-01

16

Spall behavior and damage evolution in tantalum  

SciTech Connect

The authors conducted a number of plate impact experiments using an 80-mm launcher to study dynamic void initiation, linkup, and spall in tantalum. The tests ranged in shock pressure so that the transition from void initiation, incipient spall, and full spall could be studied. Wave profiles were measured using a velocity interferometry system (VISAR), and targets were recovered using soft recovery techniques. The authors utilized scanning electron microscopy, metallographic cross-sections, and plateau etching to obtain quantitative information concerning damage evolution in tantalum under spall conditions. The data (wave profiles and micrographs) are analyzed in terms of a new theory and model of dynamic damage cluster growth. They have developed a model of ductile damage based on void coalescence of initially nucleated voids, that leads to clusters of voids. At low loading strain rates, the biggest cluster has time to grow much more rapidly than smaller clusters to break the sample. At high loading strain rates, large clusters cannot grow any faster than smaller clusters so the sample breaks when enough clusters grow independently to form a fracture surface by random accumulation.

Zurek, A.K.; Thissell, W.R.; Tonks, D.L.

1995-09-01

17

Evolution equations: Frobenius integrability, conservation laws and travelling waves  

E-print Network

We give new results concerning the Frobenius integrability and solution of evolution equations admitting travelling wave solutions. We also discuss "local" conservations laws for evolution equations in general and demonstrate all the results for the Kortweg de Vries equation.

Geoff Prince; Naghmana Tehseen

2014-09-09

18

An Evaluation of Linear Cumulative Damage (Miner's Law) Using Kinetic Crack Growth Theory  

Microsoft Academic Search

Taking a basis set of creep failure functions as specifying the failureproperties for a class of materials, various damage laws can be used topredict failure under any type of stress history. A particularlyconvenient form is that of Miner's law also known as Linear CumulativeDamage. However, such damage laws are entirely empirical and ofuncertain value. A kinetic crack growth theory developed

Richard M. Christensen

2002-01-01

19

Entropy evolution law in a laser process  

SciTech Connect

For the first time, we obtain the entropy variation law in a laser process after finding the Kraus operator of the master equation describing the laser process with the use of the entangled state representation. The behavior of entropy is determined by the competition of the gain and damping in the laser process. The evolution formula for the number of photons is also obtained. -- Highlights: •We apply the thermo-field dynamics method to the master equation of a laser. •We find the operator-sum (Kraus) representation for the density operator. •We find both the normally ordered and compact forms of ?(t) for ?{sub 0}=|z??z|. •We find the exact expression of the laser’s entropy. •Our results reveal quantitatively how a laser beam can be generated in a laser.

Chen, Jun-hua, E-mail: cjh@ustc.edu.cn; Fan, Hong-yi

2013-07-15

20

Beyond Reductionism Twice: No Laws Entail Biosphere Evolution, Formal Cause Laws Beyond Efficient Cause Laws  

E-print Network

Newton set the stage for our view of how science should be done. We remain in what I will call the `Newtonian Paradigm' in all of physics, including Newton, Einstein, and Schrodinger. As I will show shortly, Newton invented and bequeathed to us `efficient cause entailing laws' for the entire becoming of the universe. With Laplace this became the foundation of contemporary reductionism in which all that can happen in the world is due to efficient cause entailing laws. More this framework stands as our dominant way to do science. The Newtonian Paradigm has done enormous work in science, and helped lead to the Industrial Revolution, and even our entry into Modernity. In this paper I propose to challenge the adequacy of the Newtonian Paradigm on two ground: 1) For the evolution of the biosphere beyond the watershed of life, we can formulate no efficient cause entailing laws that allow us to deduce the evolution of the biosphere. A fortiori, the same holds for the evolution of the economy, legal systems, social sy...

Kauffman, Stuart

2013-01-01

21

Quasi-Static Brittle Damage Evolution in Elastic Materials with Multiple Damaged States  

NASA Astrophysics Data System (ADS)

We present energetic and strain-threshold models for the quasi-static evolution of brutal brittle damage for geometrically-linear elastic materials. By allowing for anisotropic elastic moduli and multiple damaged states we present the issues for the first time in a truly elastic setting, and show that the threshold methods developed in (Garroni, A., Larsen, C. J., Threshold-based quasi-static brittle damage evolution, Archive for Rational Mechanics and Analysis 194 (2), 585-609, 2009) extend naturally to elastic materials with non-interacting damage. We show the existence of solutions and that energetic evolutions are also threshold evolutions.

Chenchiah, Isaac Vikram; Larsen, Christopher J.

2015-03-01

22

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

23

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

24

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

25

The evolution of the power law k-essence cosmology  

NASA Astrophysics Data System (ADS)

We investigate the evolution of the power law k-essence field in FRWL spacetime. The autonomous dynamical system and critical points are obtained. The corresponding cosmological parameters, such as ? ? and w ? , are calculated at these critical points. We find it is possible to achieve an equation of state crossing through -1 for k-essence field. The results we obtained indicate that the power law k-essence dark energy model can be compatible with observations.

Yang, Rongjia; Chen, Bohai; Li, Jun; Qi, Jingzhao

2015-04-01

26

Evolution of power law distributions in science and society  

NASA Astrophysics Data System (ADS)

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.

Jeon, Young-Pyo; McCoy, Benjamin J.

2005-09-01

27

Permeability of WIPP Salt During Damage Evolution and Healing  

SciTech Connect

The presence of damage in the form of microcracks can increase the permeability of salt. In this paper, an analytical formulation of the permeability of damaged rock salt is presented for both initially intact and porous conditions. The analysis shows that permeability is related to the connected (i.e., gas accessible) volumetric strain and porosity according to two different power-laws, which may be summed to give the overall behavior of a porous salt with damage. This relationship was incorporated into a constitutive model, known as the Multimechanism Deformation Coupled Fracture (MDCF) model, which has been formulated to describe the inelastic flow behavior of rock salt due to coupled creep, damage, and healing. The extended model was used to calculate the permeability of rock salt from the Waste Isolation Pilot Plant (WIPP) site under conditions where damage evolved with stress over a time period. Permeability changes resulting from both damage development under deviatoric stresses and damage healing under hydrostatic pressures were considered. The calculated results were compared against experimental data from the literature, which indicated that permeability in damaged intact WIPP salt depends on the magnitude of the gas accessible volumetric strain and not on the total volumetric strain. Consequently, the permeability of WIPP salt is significantly affected by the kinetics of crack closure, but shows little dependence on the kinetics of crack removal by sintering.

BODNER,SOL R.; CHAN,KWAI S.; MUNSON,DARRELL E.

1999-12-03

28

The constructal law of design and evolution in nature.  

PubMed

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

2010-05-12

29

The constructal law and the evolution of design in nature.  

PubMed

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. PMID:21683663

Bejan, Adrian; Lorente, Sylvie

2011-10-01

30

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

31

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

32

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

33

A description of crevasse formation using continuum damage mechanics  

Microsoft Academic Search

Continuum damage mechanics describes the progressive deterioration of material subjected to loading. For polycrystalline ice, a local isotropic damage evolution law coupled to Glen's flow law allows the description of creep to failure. The damage evolution law has been derived from mesoscopic tests performed in traction and shearing. Damage initiation is controlled by a size dependent stress threshold, which has

Antoine Pralong; Martin Funk; Martin P. Lüthi

2003-01-01

34

Law of genome evolution direction: Coding information quantity grows  

NASA Astrophysics Data System (ADS)

The problem of the directionality of genome evolution is studied. Based on the analysis of C-value paradox and the evolution of genome size, we propose that the function-coding information quantity of a genome always grows in the course of evolution through sequence duplication, expansion of code, and gene transfer from outside. The function-coding information quantity of a genome consists of two parts, p-coding information quantity that encodes functional protein and n-coding information quantity that encodes other functional elements. The evidences on the law of the evolutionary directionality are indicated. The needs of function are the motive force for the expansion of coding information quantity, and the information quantity expansion is the way to make functional innovation and extension for a species. Therefore, the increase of coding information quantity of a genome is a measure of the acquired new function, and it determines the directionality of genome evolution.

Luo, Liao-Fu

2009-06-01

35

Mathematical Modelling of Hydraulic Permeability Evolution in the Damage Zone Surrounding Geological Faults  

NASA Astrophysics Data System (ADS)

Geological faults are planar structures, oriented in three-dimensional space, on which shear displacement has occurred. As the rock shears, the material within and around the shear plane is damaged causing a huge variability in fluid flow properties. Faults can be barriers to flow, conduits, or combinations of the two, and their hydraulic properties vary considerably over both space and time. It is critical for the prediction of both future and historical fluid (or gas) migration through fault zones to be able to assess their spatial and temporal hydraulic evolution. This is particularly relevant, due to the large timescales involved, when modelling historic migration in oil fields, or when simulating the transport of radionuclides following the deep burial of radioactive waste. Fluid flow and structural deformation are fully coupled processes within fault zones: Small scale discontinuities, such as fractures and deformation bands of reduced permeability, are formed in the damage zone surrounding faults and have a strong influence on flow properties. Fluid flow in the subsurface is traditionally modelled using Darcy's law, and structural deformation using Navier's law. The main aim of this research is to investigate and validate our understanding of these coupled processes in the damage zone surrounding faults. In the research presented here, fault zone evolution is modelled using a finite element approach. The coupled hydro-mechanical model has been developed and validated using standard benchmark data. The model has been used to simulate deformation and fluid flow in damage zone structures mapped at the Big Hole fault, Utah. Results demonstrate propagation of the existing slip surfaces leading to increased flow. The model is now being applied to explore temporal and spatial fault evolution in the Sierra Nevada based on data sets collected by Bürgmann and Pollard. Results will validate and enhance scientific understanding of the physical processes inherent in fault development. Ultimately, the model will be extended to include chemical processes such as mineralisation, and will provide an invaluable tool for predicting the heterogeneous hydrogeological properties of faults.

Willson, J. P.; Lunn, R. J.; Cowie, P.

2004-12-01

36

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

37

Law & psychiatry: the evolution of laws regulating psychiatric commitment in France.  

PubMed

This column reviews the evolution of French laws governing psychiatric commitment, culminating in the July 2011 Act, which was opposed by most professional organizations. The 2011 Act has maintained the two traditional French approaches to involuntary treatment: at the request of a third person and upon a decision by a prefect representing the government. However, the 2011 Act introduced major innovations into French practices: systematic review by a judge, a 72-hour observation period, and the possibility of compulsory community treatment. PMID:23821167

Gourevitch, Raphaël; Brichant-Petitjean, Clara; Crocq, Marc-Antoine; Petitjean, François

2013-07-01

38

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

E-print Network

if if PREDICTION OF PROXIMAL FEMORAL FRACTURE BY USING MECHANICAL QUASI-BRITTLE DAMAGE COUPLED WITH ANISOTROPIC of proximal femur. The model was developed in term of anisotropic coupled behaviour law (strain-quasi-brittle and the dependence of damage growth to the hydrostatic pressure, a quasi-brittle damage law can be expressed by

Boyer, Edmond

39

Stochastic damage evolution modeling in laminates. Ph.D. Thesis  

SciTech Connect

A stochastic mesomechanics model has been developed for damage accumulation analysis in advanced laminated composites. The model is based on a theory of excursions of random process beyond the limiting bounds. Stochastic strains in the laminate subjected to random Gaussian in-plane loading are calculated using lamination theory and random functions theory. Probabilistic variation of stiffness and strength characteristics of plies are used in the analysis. A stochastic version of maximum strain failure criterion is applied for damage probability calculation. A mesovolume concept is utilized in modeling stiffness degradation. The model is verified experimentally based on the available data. Capabilities of the model are illustrated by predictions of damage accumulation and failure in a Kevlar/epoxy (0/ +/- 30/90){sub s} laminate under quasistationary, long-term stationary, and cyclic loading. Effects of loading rate, deviation, stationary level and cyclic amplitude on damage evolution are discussed. High-cycle fatigue behavior of laminate is calculated utilizing the observed stages in failure accumulation under the cyclic loading. Percolation type analysis of damage morphology is performed for the inhomogeneous anisotropic media. The model and computer codes developed can be incorporated into structural analysis software and used in design of laminated structures.

Dzenis, Y.A.

1994-01-01

40

Generic incubation law for laser damage and ablation thresholds  

NASA Astrophysics Data System (ADS)

In multi-pulse laser damage and ablation experiments, the laser-induced damage threshold (LIDT) usually changes with the number of pulses in the train, a phenomenon known as incubation. We introduce a general incubation model based on two physical mechanisms—pulse induced change of (i) absorption and (ii) critical energy that must be deposited to cause ablation. The model is applicable to a broad class of materials and we apply it to fit data for dielectrics and metals. It also explains observed changes of the LIDT as a function of the laser repetition rate. We discuss under which conditions the crater-size method to determine LIDTs can be applied in multi-pulse experiments.

Sun, Zhanliang; Lenzner, Matthias; Rudolph, Wolfgang

2015-02-01

41

Damage initiation and propagation modeling using Energy Partitioning Damage Evolution model for Pb-free solder materials  

Microsoft Academic Search

Thermo-mechanical fatigue and damage has always been an issue for solder joint materials used in micro-electronic devices. Accurate prediction of the damage and crack is essential in order to predict the life of these joints. This paper presents a finite element modeling approach that is used in conjunction with Energy Partitioning Damage Evolution (EPDE) model to determine the state of

Leila J. Ladani

2010-01-01

42

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

43

Chromosome damage evolution after low and high LET irradiation  

NASA Astrophysics Data System (ADS)

Ionizing radiation induces DNA and chromatin lesions which are converted to chromosome lesions detected in the first post-irradiation mitosis by classic cytogenetic techniques as chromosomal aberrations (CAs). These techniques allow to monitor also delayed aberrations observed after many cell generations post-irradiation - the manifestation of chromosomal instability phenotype (CIN). The problem discussed is how to predict time evolution from initial to delayed DNA/chromosome damage. To address this question, in the present work a mechanistic model of CIN is elaborated which integrates pathways of (*) DNA damage induction and its conversion to chromosome lesions (aberrations), (**) lesion transmission and generation through cell cycles. Delayed aberrations in subsequent cycles are formed in the model owing to two pathways, DNA damage generation de novo as well as CA transmission from previous cycles. DNA damage generation rate is assumed to consist of bystander and non-bystander components. Bystander signals impact all cells roughly equally, whereas non-bystander DSB generation rate differs for the descendants of unirradiated and irradiated cells. Monte Carlo simulation of processes underlying CIN allows to predict the time evolution of initial radiation-induced damage - kinetics curve for delayed unstable aberrations (dicentrics) together with dose response and RBE as a function of time after high vs low LET irradiation. The experimental data for radiation-induced CIN in TK6 lymphoblastoid cells and human lymphocytes irradiated with low (gamma) and high (Fe, C) LET radiation are analyzed on the basis of the proposed model. One of the conclusions is that without bystander signaling, just taking into account the initial DNA damage and non-bystander DSB generation, it is impossible to describe the available experimental data for high-LET-induced CIN. The exact contribution of bystander effects for high vs low LET remains unknown, but the relative contribution may be assessed at large times after initial acute irradiation. RBE for delayed aberrations depends on LET, time and cell line, which probably reflects a genetic background for bystander component. The proposed modeling approach creates a basis for integration of complex network of bystander/inflammatory signaling in systems-level platform for quantification of radiation induced CIN.

Andreev, Sergey; Eidelman, Yuri

44

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

45

[A case of law-evading herbs poisoning that induced shock and myocardial damage].  

PubMed

Law-evading herbs may induce poisoning symptoms, especially when they contain synthetic cannabinoids. However, their detailed pharmacological effects have not yet been clarified. Some reports have previously described symptoms of poisoning, but only a few reports have so far described shock and myocardial damage (MD). We experienced a case of shock and MD in a patient who had smoked law-evading herbs. A 61-year-old male presented at an emergency department 8 hours after smoking law-evading herbs (Rush Trip, High Men Monster) with chest pain. A vasopressor agent was administered to treat shock and antiarrhythmic drugs were administered due to ventricular arrhythmia. The contents of the law-evading herbs were unknown, so an in-hospital follow-up was conducted to treat the patient's symptoms. The follow-up blood test showed an increased level of cardiac enzymes, which thereafter demonstrated a spontaneous remission. The systemic conditions tended to improve and the patient was discharged from the hospital on the 5th hospital day. The contents of the law-evading herbs in question were thereafter,analyzed, and synthetic cannabinoids (JWH-210, JWH-081 and JWH-122) as well as caffeine were detected. The cause for the poisoning symptoms were suspected to be the presence of synthetic cannabinoids and caffeine. Such law-evading herbs may contain synthetic cannabinoids and caffeine which both may induce shock and MD. PMID:25771668

Nakamura, Yoshihiko; Nakano, Minoru; Nakamura, Mitsunobu; Miyazaki, Dai; Okamori, Satoshi; Akuzawa, Hisashi; Yuasa, Masahiro

2014-12-01

46

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

47

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

48

The Evolution of Health Care Advance Planning Law and Policy  

PubMed Central

Context: The legal tools of health care advance planning have substantially changed since their emergence in the mid-1970s. Thirty years of policy development, primarily at the state legislative level addressing surrogate decision making and advance directives, have resulted in a disjointed policy landscape, yet with important points of convergence evolving over time. An understanding of the evolution of advance care planning policy has important implications for policy at both the state and federal levels. Methods: This article is a longitudinal statutory and literature review of health care advance planning from its origins to the present. Findings: While considerable variability across the states still remains, changes in law and policy over time suggest a gradual paradigm shift from what is described as a “legal transactional approach” to a “communications approach,” the most recent extension of which is the emergence of Physician Orders for Life-Sustaining Treatment, or POLST. The communications approach helps translate patients’ goals into visible and portable medical orders. Conclusions: States are likely to continue gradually moving away from a legal transactional mode of advance planning toward a communications model, albeit with challenges to authentic and reliable communication that accurately translates patients’ wishes into the care they receive. In the meantime, the states and their health care institutions will continue to serve as the primary laboratory for advance care planning policy and practice. PMID:20579283

Sabatino, Charles P

2010-01-01

49

A revised rate- and state-dependent friction law obtained by constraining constitutive and evolution laws separately with laboratory data  

NASA Astrophysics Data System (ADS)

We propose two major revisions on the rate- and state-dependent friction (RSF) law on the basis of rigorous analysis of friction experiments. First, we find that the direct effect coefficient a, a parameter playing a central role in the RSF constitutive law, is much larger than the traditional, consensual estimate of less than about 0.01. We derive a lower bound of 0.035 for a directly from stress-velocity relations measured during carefully designed step tests, without relying on any evolution laws as traditional methods do. After correcting for state changes during the steps, inferred indirectly from observed changes in acoustic transmissivities across the interface, we obtain an estimate of a as large as 0.05. Second, we calculate values of the RSF state variable ? by feeding the measured shear stress and slip velocity values into the constitutive law. The results showed systematic deviations from predictions of the RSF evolution law of the aging type. This leads us to propose a revised evolution law, which incorporates a previously unknown weakening effect related to the shear stress. We also present additional experiment results to corroborate the presence of this new effect. Forward simulations based on our revised evolution law, combined with the larger, revised value of a, very well explain observed variations in both the shear stress and ? throughout different phases of experiments, including quasi-static hold, reloading after a hold, and steady state sliding at different velocities, as well as their mutual transitions, all with an identical set of parameter values.

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

2012-02-01

50

Constructal law of design and evolution: Physics, biology, technology, and society  

NASA Astrophysics Data System (ADS)

This is a review of the theoretical and applied progress made based on the Constructal law of design and evolution in nature, with emphasis on the last decade. The Constructal law is the law of physics that accounts for the natural tendency of all flow systems (animate and inanimate) to change into configurations that offer progressively greater flow access over time. The progress made with the Constructal law covers the broadest range of science, from heat and fluid flow and geophysics, to animal design, technology evolution, and social organization (economics, government). This review presents the state of this fast growing field, and draws attention to newly opened directions for original research. The Constructal law places the concepts of life, design, and evolution in physics.

Bejan, Adrian; Lorente, Sylvie

2013-04-01

51

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

52

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

53

A continuum theory of grain size evolution and damage and D. Bercovici2  

E-print Network

(``healing'') laws employed by these models are derived from normal grain growth or coarsening theory, which standard mass, momentum, and energy conservation, as well as entropy production, on a statistically laws for grain growth and reduction); grain size evolution thus incorporates the free energy

54

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.

55

Effect of strain rate on damage evolution in a cast Al-Si-Mg base alloy  

Microsoft Academic Search

An important aspect of damage evolution in cast Al-Si-Mg base alloys is fracture\\/cracking of Si particles. This microstructural\\u000a damage is quantitatively characterized as a function of strain rate in the range 10?4 to 3.7 10+3, at an approximately constant uniaxial compressive strain level (20 to 25 pct). It is shown that the fraction of damaged\\u000a silicon particles, their average size,

Manish D. Dighe; Arun M. Gokhale; Mark F. Horstemeyer; D. A. Mosher

2000-01-01

56

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

57

Extension of the spectral-transform method for solving nonlinear evolution equations and related conservation laws  

Microsoft Academic Search

Summary  The spectral-transform method for solving nonlinear evolution equations is extended to certain classes of matrix equations\\u000a with linearlyx-dependent coefficients and the existence of the conservation laws for the new class of nonlinear evolution equations is investigated.\\u000a A remarkably explicit representation is, moreover, obtained for the conserved quantities of the «old» classes of nonlinear\\u000a evolution equations (withx-independent coefficients).

L. Pilloni

1980-01-01

58

A continuum model for damage evolution in laminated composites  

NASA Technical Reports Server (NTRS)

The accumulation of matrix cracking is examined using continuum damage mechanics lamination theory. A phenomenologically based damage evolutionary relationship is proposed for matrix cracking in continuous fiber reinforced laminated composites. The use of material dependent properties and damage dependent laminate averaged ply stresses in this evolutionary relationship permits its application independently of the laminate stacking sequence. Several load histories are applied to crossply laminates using this model, and the results are compared to published experimental data. The stress redistribution among the plies during the accumulation of matrix damage is also examined. It is concluded that characteristics of the stress redistribution process could assist in the analysis of the progressive failure process in laminated composites.

Lo, D. C.; Allen, D. H.; Harris, C. E.

1991-01-01

59

Computational modeling of damage evolution in unidirectional fiber reinforced ceramic matrix composites  

E-print Network

mechanical re- sponse of a ceramic matrix composite is simulated by a numerical model for a ®ber-matrix unitComputational modeling of damage evolution in unidirectional fiber reinforced ceramic matrix evolution in brittle matrix composites was developed. This modeling is based on an axisymmetric unit cell

Ortiz, Michael

60

Structural damage evolution assessment using the regularised time step integration method  

NASA Astrophysics Data System (ADS)

This paper presents an approach to identify both the location and severity evolution of damage in engineering structures directly from measured dynamic response data. A relationship between the change in structural parameters such as stiffness caused by structural damage development and the measured dynamic response data such as accelerations is proposed, on the basis of the governing equations of motion for the original and damaged structural systems. Structural damage parameters associated with time are properly chosen to reflect both the location and severity development over time of damage in a structure. Basic equations are provided to solve the chosen time-dependent damage parameters, which are constructed by using the Newmark time step integration method without requiring a modal analysis procedure. The Tikhonov regularisation method incorporating the L-curve criterion for determining the regularisation parameter is then employed to reduce the influence of measurement errors in dynamic response data and then to produce stable solutions for structural damage parameters. Results for two numerical examples with various simulated damage scenarios show that the proposed method can accurately identify the locations of structural damage and correctly assess the evolution of damage severity from information on vibration measurements with uncertainties.

Chen, Hua-Peng; Maung, Than Soe

2014-09-01

61

Evolution of damage during deformation in porous granular materials (Louis Néel 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

62

Survival of the fittest: Law of evolution or law of probability?  

Microsoft Academic Search

In a recent issue of Biology and Philosophy, Kenneth Waters argues that the principle of ”survival of the fittest” should be eliminated from the theory of natural selection, because it is an untestable law of probability, and as such, has no place in evolutionary theory. His argument is impressive, but it does not do justice to the practice of biology.

David B. Resnik

1988-01-01

63

The Evolution of the Exponent of Zipf's Law in Language Ontogeny  

PubMed Central

It is well-known that word frequencies arrange themselves according to Zipf's law. However, little is known about the dependency of the parameters of the law and the complexity of a communication system. Many models of the evolution of language assume that the exponent of the law remains constant as the complexity of a communication systems increases. Using longitudinal studies of child language, we analysed the word rank distribution for the speech of children and adults participating in conversations. The adults typically included family members (e.g., parents) or the investigators conducting the research. Our analysis of the evolution of Zipf's law yields two main unexpected results. First, in children the exponent of the law tends to decrease over time while this tendency is weaker in adults, thus suggesting this is not a mere mirror effect of adult speech. Second, although the exponent of the law is more stable in adults, their exponents fall below 1 which is the typical value of the exponent assumed in both children and adults. Our analysis also shows a tendency of the mean length of utterances (MLU), a simple estimate of syntactic complexity, to increase as the exponent decreases. The parallel evolution of the exponent and a simple indicator of syntactic complexity (MLU) supports the hypothesis that the exponent of Zipf's law and linguistic complexity are inter-related. The assumption that Zipf's law for word ranks is a power-law with a constant exponent of one in both adults and children needs to be revised. PMID:23516390

Baixeries, Jaume; Elvevåg, Brita; Ferrer-i-Cancho, Ramon

2013-01-01

64

Rheological Control of Interbedded Siliciclastic Strata on Damage Zone Evolution During Fault Growth  

NASA Astrophysics Data System (ADS)

Fault damage zones can have a major impact on fluid flow through sub-surface reservoirs. The typical resolution of seismic reflection data is such that faults with throws <15m are not imaged, and those with throws >15 m are imaged as discrete planes, revealing none of the smaller scale architecture of the fault damage zones. Previous field studies show that damage zone width scales with fault throw, which suggests that a relationship exists between fault growth and increasing damage zone width. However, this hypothesis remains largely untested and the factors controlling damage zone evolution are poorly understood. This study develops kinematic models to describe the evolution of damage zones during fault growth. The predictions of these models are tested against quantitative geometric attributes of natural fault damage zones preserved in siliciclastic sand/shale sequences from the Carboniferous Northumberland Basin, NE England. These data, obtained from faults with throws spanning 0.1-20 m, were measured from detailed (cm-resolution) digital outcrop models captured using terrestrial laser scanning techniques. Study locations include areas of active open-cast coal mining that provide good 3D exposure of faults during progressive coal extraction. The damage zones comprise complex arrays of structural elements including: fault splays and oversteps; drag folds; rotated fault-bound blocks; sub-parallel fracture sets and ductile shear zones; cataclasite lenses; and intensely deformed scaly gouge. We propose two complimentary kinematic models to explain the structural relationships observed within these damage zones. The first model predicts the development of cataclasite lenses from fault-bounded blocks in contractional oversteps with increasing fault throw. In this scenario, the damage zone width remains approximately constant, defined by the initial fault separation. The second model describes the space incompatibility that develops between discrete fault planes in coherent sandstone layers and wider damage zones in adjacent shales where throw is distributed along sub-parallel fracture sets and ductile shear zones. In this scenario, damage zone width may increase with increasing fault throw. Alternatively, the width of the damage zone may be controlled by thickness of the rheologically weaker shale. These geologically-based models highlight the importance of bed thickness and rheology - in addition to fault throw - in controlling damage zone evolution and provide a basis for predicting the likely sizes of different damage zone elements associated with seismically-imaged faults in the subsurface.

Wightman, R. H.; Imber, J.; Healy, D.; Holdsworth, R. E.; McCaffrey, K. J.; Jones, R. R.

2006-12-01

65

Radiation-induced damage and evolution of defects in Mo  

Microsoft Academic Search

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

Sergey V. Starikov; Zeke Insepov; Jeffrey Rest; Alexey Yu. Kuksin; Genri E. Norman; Vladimir V. Stegailov; Alexey V. Yanilkin

2011-01-01

66

Dynamic damage model of crevasse opening and application to glacier calving  

Microsoft Academic Search

Theory and applications of continuum damage mechanics for ice are discussed, and on this basis, an ice damage model, valid at low stresses, is proposed. The model describes the damage itself, the rheology of the damaged ice, and the damage evolution. A local damaging and healing law is considered, and its parameterization is motivated. The model parameters are inferred from

A. Pralong; M. Funk

2005-01-01

67

Damage evolution in adhesive joints subjected to impact fatigue  

NASA Astrophysics Data System (ADS)

There is increasing interest in the effects of low-velocity impacts produced in components and structures by vibrating loads. This type of loading is known as impact-fatigue. The main aim of this paper is to investigate the behaviour of adhesive joints exposed to low-velocity impacting, to study the impact-fatigue life and to compare this loading regime with standard fatigue (i.e. non-impacting, constant amplitude, sinusoidal fatigue). To this effect, bonded aluminium single lap joints have been subjected to multiple impacting tensile loads and it has been shown that this is an extremely damaging load regime compared to standard fatigue. Two modifications of the accumulated time-stress model have been proposed to characterise the impact-fatigue results presented in this paper. The first model has been termed the modified load-time model and relates the total cumulative loading time of the primary tensile load wave to the mean maximum force. The second model attempts to characterise sample damage under impact-fatigue by relating the maximum force normalised with respect to initial maximum force to the accumulated loading time normalised with respect to the total accumulated loading time. This model has been termed the normalised load-time model. It is shown that both models provide a suitable characterisation of impact-fatigue in bonded joints.

Casas-Rodriguez, J. P.; Ashcroft, I. A.; Silberschmidt, V. V.

2007-12-01

68

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

69

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

70

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

E-print Network

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

Badyaev, Alex

71

Damage evolution in Au-implanted Ho2Ti2O7 titanate pyrochlore  

SciTech Connect

Damage evolution at room temperature in Ho2Ti2O7 single crystals is studied under 1 MeV Au2+ ion irradiation by Rutherford backscattering spectroscopy along the <001> direction. For a better determination of ion-induced disorder profile, an iterative procedure and a Monte Carlo code (McChasy) were used to analyze ion channeling spectra. A disorder accumulation model, with contributions from the amorphous fraction and the crystalline disorder, is fit to the Ho damage accumulation data. The damage evolution behavior indicates that the relative disorder on the Ho sublattice follows a nonlinear dependence on dose and that defect-stimulated amorphization is the primary amorphization mechanism. Similar irradiation behavior previously was observed in Sm2Ti2O7. A slower damage accumulation rate for Ho2Ti2O7, as compared with damage evolution in Sm2Ti2O7, is mainly attributed to a lower effective cross section for defect-simulated amorphization.

Zhang, Yanwen; Jagielski, Jacek; Bae, In-Tae; Xiang, Xia; Thome, Lionel; Balakrishnan, G.; Paul, D. M.; Weber, William J.

2010-10-01

72

No entailing laws, but enablement in the evolution of the biosphere  

E-print Network

Biological evolution is a complex blend of ever changing structural stability, variability and emergence of new phenotypes, niches, ecosystems. We wish to argue that the evolution of life marks the end of a physics world view of law entailed dynamics. Our considerations depend upon discussing the variability of the very "contexts of life": the interactions between organisms, biological niches and ecosystems. These are ever changing, intrinsically indeterminate and even unprestatable: we do not know ahead of time the "niches" which constitute the boundary conditions on selection. More generally, by the mathematical unprestatability of the "phase space" (space of possibilities), no laws of motion can be formulated for evolution. We call this radical emergence, from life to life. The purpose of this paper is the integration of variation and diversity in a sound conceptual frame and situate unpredictability at a novel theoretical level, that of the very phase space. Our argument will be carried on in close compar...

Longo, Giuseppe; Kauffman, Stuart

2012-01-01

73

von Baer's law for the ages: lost and found principles of developmental evolution.  

PubMed

In 1828, Karl Ernst von Baer formulated a series of empirically defined rules, which became widely known as the 'Law of Development' or 'von Baer's law of embryology'. This was one the most significant attempts to define the principles that connected morphological complexity and embryonic development. Understanding this relation is central to both evolutionary biology and developmental genetics. Von Baer's ideas have been both a source of inspiration to generations of biologists and a target of continuous criticism over many years. With advances in multiple fields, including paleontology, cladistics, phylogenetics, genomics, and cell and developmental biology, it is now possible to examine carefully the significance of von Baer's law and its predictions. In this review, I argue that, 185 years after von Baer's law was first formulated, its main concepts after proper refurbishing remain surprisingly relevant in revealing the fundamentals of the evolution-development connection, and suggest that their explanation should become the focus of renewed research. PMID:24120296

Abzhanov, Arhat

2013-12-01

74

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

75

Numerical Simulations of Inter-laminar Damage Evolution in a Composite Wing Box  

NASA Astrophysics Data System (ADS)

In this paper, a numerical study has been carried out on skin delamination and skin-stringer debonding growth in a composite wing-box under compressive loading conditions. The adopted numerical models use the Virtual Crack Closure Technique to simulate the inter-laminar damage evolution and the numerical analyses have been performed by means of the FEM code ABAQUS and B2000++. The obtained numerical results have been assessed and compared each other in terms of delaminated area evolution, delamination growth initiation load and strain distributions. In order to investigate the effectiveness of the adopted numerical platforms in predicting the evolution of inter-laminar damages, comparisons with experimental data, in terms of load displacement curves and strains in the debonding area, have been also introduced.

Riccio, A.; Raimondo, A.; Borrelli, R.; Mercurio, U.; Tescione, D.; Scaramuzzino, F.

2014-06-01

76

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

77

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

78

Finite element prediction of proximal femur fracture pattern based on orthotropic behaviour law coupled to quasi-brittle damage.  

PubMed

The purpose of this study was to develop a finite element model based on continuum damage mechanics in order to simulate the profile of the fractured area of proximal femur and the complete force-displacement curve from the beginning until complete fracture. The model was developed in term of anisotropic behaviour law coupled to quasi-brittle damage to describe the progressive crack initiation and propagation within proximal femoral. A damage law was developed and implemented into a finite element code (Abaqus) based on experimental observations. To illustrate the potential of the current approach, the right adult human femur previously investigated by Keyak and Falkinstein (Model B: male, age 61) was simulated until complete fracture under one-legged stance load. The femur fracture profile was predicted and compared to clinical observed results. Good agreements were obtained suggesting that the proposed damage model could be used correctly to simulate the force-displacement curve, the fracture type and to simulate the progressive propagation of the crack paths. Present model can contribute towards the development of diagnostic tool that can detect osteoporotic fracture for aged patients in an early stage and predict bone strength accurately. PMID:21824797

Hambli, Ridha; Bettamer, Awad; Allaoui, Samir

2012-03-01

79

The relationship between microstructure and damage evolution in hot-rolled complex-phase steel sheet  

NASA Astrophysics Data System (ADS)

Complex-phase (CP) steels are employed in applications that require high-strength and good edge formability. These steels derive their strength from a fine-grained bainite-ferrite microstructure, and alloying to provide solid-solution and precipitation strengthening. CP steels are produced industrially through a process of controlled rolling and cooling to produce desirable microstructures. Hole-expansion tests are typically used as a measure of edge formability for applications such as stretch-flanges. It has been shown that CP microstructures are susceptible to large fluctuations in hole-expansion performance with little change in processing or resulting tensile properties. The steel's characteristics of damage evolution are critical to the hole-expansion performance. This study investigates the role of microstructure in the development of damage in CP microstructural variants. Two variant pairs of different thicknesses were produced from the leading and trailing edge of industrially produced hot-rolled sheet. Each pair consisted of a variant with poor hole-expansion performance, and a variant with good hole-expansion performance. Each variant was tested via interrupted double-notched uniaxial tension testing to induce damage. Damage evolution in each variant was quantified by X-ray micro-computed tomography (XmicroCT), and supplementary optical micrography. The damage results were correlated with microstructural characteristics. It was shown that poor hole-expansion variants failed by intergranular fracture. In these variants, void damage induced by hard martensite and retained austenite was not critical in producing failure. Purely void-damaged microstructures failed by ductile fracture, whereas cracked microstructures failed in a mixed brittle-ductile failure initiated by planar cracks. Microstructural banding of large elongated ferrite grains correlated with the existence of intergranular planar fractures.

Bell, Grant A. S.

80

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

81

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

82

The Influence of Grain Boundary Type upon Damage Evolution at Grain Boundary Interfaces  

SciTech Connect

In a prior work, it was found that grain boundary structure strongly influences damage evolution at grain boundaries in copper samples subjected to either shock compression or incipient spall. Here, several grain boundaries with different grain boundary structures, including a {Sigma}3 (10-1) boundary, are interrogated via conventional transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) to investigate the effects of atomic-scale structural differences on grain boundary strength and mobility. Boundaries are studied both before and after shock compression at a peak shock stress of 10 GPa. Results of the TEM and HRTEM work are used in conjunction with MD modeling to propose a model for shock-induced damage evolution at grain boundary interfaces that is dependent upon coincidence.

Perez-Bergquist, Alejandro G [Los Alamos National Laboratory; Brandl, Christian [Los Alamos National Laboratory; Escobedo, Juan P [Los Alamos National Laboratory; Trujillo, Carl P [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray III, George T [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory

2012-07-09

83

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

84

Materials Science and Engineering A 443 (2007) 115 Damage evolution in Ti6Al4VAl3Ti metal-intermetallic  

E-print Network

behavior; Damage evolution; Crack density 1. Introduction Intermetallics are phases or compounds formedMaterials Science and Engineering A 443 (2007) 1­15 Damage evolution in Ti6Al4V­Al3Ti metal-intermetallic May 2006; accepted 5 May 2006 Abstract The crack propagation and damage evolution in metal (Ti6Al4V)-intermetallic

Meyers, Marc A.

85

Deterministic and stochastic analysis of size effects and damage evolution in quasi-brittle materials  

Microsoft Academic Search

Summary   This study presents some recent results on damage evolution in quasi-brittle materials including stochastic imperfections.\\u000a The material strength is described as a random field and coupled to the response. The most probable configurations of imperfections\\u000a leading to failure are sought by means of an optimisation algorithm. This allows for evaluation of the significance of different\\u000a modes and of the

M. A. Gutiérrez; R. De Borst

1999-01-01

86

Damage evolution in GLARE fibre-metal laminate under repeated low-velocity impact tests  

NASA Astrophysics Data System (ADS)

An experimental study was performed on the repeated low-velocity impact behaviour of GLARE. Damage evolution in the material constituents was characterised with successive number of impacts. Records were correlated with visual inspection, ultrasound C-scan and chemical etching. The stiffness of the plate varied when cumulating the number of impacts. Damage accumulation was limited thanks to the synthesis of unidirectional composite and metal. The glass/epoxy plies with high elastic tensile strength could withstand several impacts before perforation despite delamination growth in the vicinity of the impacted area. The damage tolerant aluminium layers prevented the penetration of the projectile and avoided the expansion of delamination. This efficient mechanism preserved the structural integrity of GLARE until first aluminium cracking at the non-impacted side. Among the different failure modes, plate deformation absorbed most of the impact energy. The findings will support the development of a generic quasi-static analytical model and numerical methods.

Morinière, Freddy D.; Alderliesten, René C.; Tooski, Mehdi Yarmohammad; Benedictus, Rinze

2012-12-01

87

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

E-print Network

with reference to both Shariah and Saudi Arabia law. Consequently, legal and Shariah solutions should be provided. This dissertation is a comprehensive study of credit reporting damage and remedies. It tackles issues related to definitions, history...

Alhaidary, Mansour

2012-05-31

88

The Evolution of Law Library Support to Law School Administrative and Staff Offices: What We are Doing and Why  

Microsoft Academic Search

This article looks at what law librarians are doing to support law school administrative and staff offices. The history of academic law libraries explains why this area of public services has been slow to develop. The article then discusses the type of services currently provided, including researching alumni for the alumni development staff, developing content for law school Websites, and

Leah Sandwell-Weiss

2007-01-01

89

A modified star formation law as a solution to open problems in galaxy evolution  

NASA Astrophysics Data System (ADS)

In order to reproduce the low-mass end of the stellar mass function, most current models of galaxy evolution invoke very efficient supernova feedback. This solution seems to suffer from several shortcomings however, like predicting too little star formation (SF) in low-mass galaxies at z= 0. In this work, we explore modifications to the SF law as an alternative solution to achieve a match to the stellar mass function. This is done by applying semi-analytic models based on De Lucia & Blaizot, but with varying SF laws, to the Millennium and Millennium-II simulations, within the formalism developed by Neistein & Weinmann. Our best model includes lower SF efficiencies than predicted by the Kennicutt-Schmidt law at low stellar masses, no sharp threshold of cold gas mass for SF and an SF law that is independent of cosmic time. These simple modifications result in a model that is more successful than current standard models in reproducing various properties of galaxies less massive than 1010 M?. The improvements include a good match to the observed autocorrelation function of galaxies, an evolution of the stellar mass function from z= 3 to z= 0 similar to observations and better agreement with observed specific SF rates. However, our modifications also lead to a dramatic overprediction of the cold mass content of galaxies. This shows that finding a successful model may require fine-tuning of both SF and supernova feedback, as well as improvements on gas cooling, or perhaps the inclusion of a yet unknown process which efficiently heats or expels gas at high redshifts.

Wang, Lan; Weinmann, Simone M.; Neistein, Eyal

2012-04-01

90

Damage Evolution in GaN Under MeV Heavy Ion Implantation  

SciTech Connect

Damage evaluation processes in patterned GaN implanted by 3 MeV Au2+ ions were investigated as function of ion fluences and annealing temperatures. Surface swelling was observed by using AFM and the results showed that the swelling height depends on ion fluence and annealing temperature. A four-stage of implantatation-induced damage evolution, including point defects, defect clustering, disordering or amorphization and even decomposition, was found and was contributed to defect formation, accumulation and N bubble formation induced at different level of dpa. Crater-like holes were observed on the surface of GaN implanted at the ion fluence of 2×1016 cm-2, and it is considered as an evidence of N loss and broken bubbles formed during implantation.

Gao, Yuan; Xue, Jianming; Zhang, Dongzheng; Wang, Zilong; Lan, Chune; Yan, Sha; Wang, Yugang; Xu, Fujun; Shen, Bo; Zhang, Yanwen

2009-10-22

91

Damage evolution and residual stresses in plasma-sprayed zirconia thermal barrier coatings.  

SciTech Connect

Air-plasma-sprayed zirconia thermal barrier coatings were subjected to thermal cycling and residual stress evolution in thermally grown oxide scale was studied by micro- and macro-ruby fluorescence spectroscopy. The macro approach reveals that compressive stress in the oxide scale increases with increasing number of thermal cycles (and thus increasing scale thickness), reaching a value of 1.8 GPa at a scale thickness of 3-4 {micro}m (80 cycles). Micro-ruby fluorescence spectroscopy indicates that protrusions of the zirconia top coat into the bond coat act as localized areas of high stress concentration, leading to damage initiation during thermal cycling.

Singh, J. P.

1999-02-03

92

Procedure for tracking damage evolution and predicting remaining useful life with application to an electromechanical experiment system  

NASA Astrophysics Data System (ADS)

A general method for tracking the evolution of hidden damage processes and predicting remaining useful life is presented and applied experimentally to an electromechanical system with a failing supply battery. The fundamental theory for the method is presented. In this theory, damage processes are viewed as occurring in a hierarchical dynamical system consisting of 'fast', directly observable subsystem coupled with a 'slow', hidden subsystem describing damage evolution. In the algorithm, damage tracking is achieved using a two-time-scale modeling strategy based on phase space reconstruction. Using the reconstructed phase space of the reference (undamaged) system, short-time predictive models are constructed. Fast-time data from later stages of damage evolution of a given system are collected and used to estimate the short time reference model prediction error or a tracking metric. The tracking metric is used as an input to a nonlinear recursive filter, the output of which provides an estimate of the current damage state. Estimates of remaining useful life are obtained recursively using the current damage state estimates under the assumption of a particular battery voltage evolution model. In the experimental application, the method is shown to accurately estimate both the battery state and the time to failure throughout the whole experiment.

Chelidze, David; Cusumano, Joseph P.; Chatterjee, Anindya

2001-07-01

93

Culture and the Constructal-Law evolution of the human and machine species. Comment on “An evolutionary framework for cultural change: Selectionism versus communal exchange” by L. Gabora  

NASA Astrophysics Data System (ADS)

Culture and the evolution of culture are manifestations of the physics phenomenon of design generation and evolution. The constructal law is the law of physics of the “design” phenomena in nature, including the evolution of culture. The evolutionary phenomena of creativity, science, technology, networks, hierarchy and communal exchange are features of the constructal design of nature.

Bejan, Adrian

2013-06-01

94

An incremental-iterative method for modeling damage evolution in voxel-based microstructure models  

NASA Astrophysics Data System (ADS)

Numerical methods motivated by rapid advances in image processing techniques have been intensively developed during recent years and increasingly applied to simulate heterogeneous materials with complex microstructure. The present work aims at elaborating an incremental-iterative numerical method for voxel-based modeling of damage evolution in quasi-brittle microstructures. The iterative scheme based on the Lippmann-Schwinger equation in the real space domain (Yvonnet, in Int J Numer Methods Eng 92:178-205, 2012) is first cast into an incremental form so as to implement nonlinear material models efficiently. In the proposed scheme, local strain increments at material grid points are computed iteratively by a mapping operation through a transformation array, while local stresses are determined using a constitutive model that accounts for material degradation by damage. For validation, benchmark studies and numerical simulations using microtomographic data of concrete are performed. For each test, numerical predictions by the incremental-iterative scheme and the finite element method, respectively, are presented and compared for both global responses and local damage distributions. It is emphasized that the proposed incremental-iterative formulation can be straightforwardly applied in the framework of other Lippmann-Schwinger equation-based schemes, like the fast Fourier transform method.

Zhu, Qi-Zhi; Yvonnet, Julien

2015-02-01

95

Effect of stress triaxiality corrected plastic flow on ductile damage evolution in the framework of continuum damage mechanics  

Microsoft Academic Search

Most of the damage models derived from the theory of Lema??tre have been developed using the hypothesis based on “proportional loading” for the determination of some material parameters. This hypothesis is adopted in such a way that a material coefficient (a scale factor for damage values) can be evaluated from tensile tests on unnotched specimens, considering the triaxiality of the

G. La Rosa; G. Mirone; A. Risitano

2001-01-01

96

Tool Life Prediction for Ceramic Tools in Intermittent Turning of Hardened Steel Based on Damage Evolution Model  

NASA Astrophysics Data System (ADS)

Al2O3-based ceramic is one of the most widely used materials for tools employed in hardened steel turning applications due to its high hardness, wear resistance, heat resistance and chemical stability. The objective of this work is to predict the lives of Al2O3-(W, Ti)C ceramic tools in intermittent turning of hardened AISI 1045 steel by means of damage evolution model taking into account the mechanical loading and thermal effect in the cutting process. A damage evolution model analyzing the RVE with uniformly distributed interacting cracks is constructed based on micromechanics. The calculated results of the proposed damage evolution model are compared with the lives of two kinds of Al2O3-(W, Ti)C ceramic tools obtained through experiments. It is found that the proposed model can be used to predict the lives of the ceramic cutting tools in intermittent turning operation.

Cui, Xiaobin; Zhao, Jun; Zhou, Yonghui; Zheng, Guangming

2011-07-01

97

On potential problems in micromechanics approach to damage evolution in composite materials  

SciTech Connect

The common modes of damage in composite materials consist of multiple cracking in preferred orientations. A given family of parallel cracks tends to evolve under subjected loading by increasing its number density. Depending on the constraints imposed by the heterogeneities of the microstructure, a family of cracks may tend to an asymptotic state of saturation or bifurcate into another mode. Most micromechanics analyses adopt procedures, by assuming unit cell geometry and periodicity, that restrict the evolution to self-similar forms, thereby suppressing mode bifurcation. This inherent limitation of such micromechanics approaches will be discussed in this paper. An example of cross ply laminates with transverse cracking will be taken to illustrate the problems.

Talreja, R. [Georgia Institute of Technology, Atlanta, GA (United States)

1995-12-31

98

Relating damage evolution of concrete cooled to cryogenic temperatures to permeability  

NASA Astrophysics Data System (ADS)

Typically, 9% Ni steel is used for primary containment of liquefied natural gas (LNG). Utilization of concrete in place of 9% Ni steel for primary containment would lead to significant cost savings. Hence, this study investigates changes in the microstructure of concrete due to cryogenic freezing that would affect its relevant engineering properties for containment. The study also evaluates the effect of aggregate type on the damage potential of concrete subjected to cryogenic freezing. The aim is to investigate design methodologies to produce damage-resistant cryogenic concrete. The study employed four concrete mixture designs involving river sand as fine aggregate, and coarse aggregates with different coefficient of thermal expansion (CTE) values. Specifically, the coarse aggregates were limestone, sandstone, trap rock and lightweight aggregate. Concrete cubes were cured under water for at least 28 days and thereafter frozen from ambient (20 °C) to cryogenic temperature (-165 °C). Acoustic emission (AE) sensors were placed on the concrete cubes during freezing. X-ray computed tomography (XRCT) was employed to study the microstructure of concrete cores, before and after cryogenic freezing. The impact of the microstructural evolution thus obtained from AE and XRCT on relevant engineering properties was determined via water and chloride permeability tests. Microcrack propagation determined from AE correlated with changes in permeability. There were no observable cracks in majority of the concrete mixtures after freezing. This implies that microcracks detected via AE and increased permeability was very well distributed and smaller than the XRCT's resolution. Damage (microcracking) resistance of the concrete with different aggregates was in the order limestone ? trap rock ? lightweight aggregate ? sandstone.

Kogbara, Reginald B.; Iyengar, Srinath R.; Grasley, Zachary C.; Rahman, Syeda; Masad, Eyad A.; Zollinger, Dan G.

2014-11-01

99

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

NASA Astrophysics Data System (ADS)

Earthquake 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

100

Damage evolution in uniaxial silicon carbide fiber-reinforced titanium matrix composites  

NASA Astrophysics Data System (ADS)

Fiber fractures initiate damage zones ultimately determining the strength and lifetime of metal matrix composites (MMCs). The evolution of damage in a MMC comprising a row of unidirectional SiC fibers (32 vol.%) surrounded by a Ti matrix was examined using X-ray microdiffraction (gym beam size) and macrodiffraction (mm beam size). A comparison of high-energy X-ray diffraction (XRD) techniques including a powerful two-dimensional XRD method capable of obtaining powder averaged strains from a small number of grains is presented (HEmuXRD2). Using macrodiffraction, the bulk residual strain in the composite was determined against a true strain-free reference. In addition, the bulk in situ response of both the fiber reinforcement and the matrix to tensile stress was observed and compared to a three-dimensional finite element model. Using microdiffraction, multiple strain maps including both phases were collected in situ before, during, and after the application of tensile stress, providing an unprecedented detailed picture of the micromechanical behavior in the laminate metal matrix composite. Finally, the elastic axial strains were compared to predictions from a modified shear lag model, which unlike other shear lag models, considers the elastic response of both constituents. The strains showed excellent correlation with the model. The results confirmed, for the first time, both the need and validity of this new model specifically developed for large scale multifracture and damage evolution simulations of metal matrix composites. The results also provided unprecedented insight for the model, revealing the necessity of incorporating such factors as plasticity of the matrix, residual stress in the composite, and selection of the load sharing parameter. The irradiation of a small number of grains provided strain measurements comparable to a continuum mechanical state in the material. Along the fiber axes, thermal residual stresses of 740 MPa (fibers) and +350 MPa (matrix) were found. Local yielding was observed by 500 MPa in the bulk matrix of the composite. Plastic anisotropy was observed in the matrix. The intergranular strains in the Ti matrix varied as much as 50%. In spite of this variation, the HEmuXRD2 technique powerfully provided reliable information from the matrix as well as the fibers.

Hanan, Jay Clarke

101

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

102

An anisotropic mechanical fatigue damage evolution model for Pb-free solder materials  

Microsoft Academic Search

Evaluating state of damage in a ductile material as it experiences mechanical fatigue and cyclic loading poses much complexity, and has been the subject of many researches. This study revisits the anisotropic damage model developed by Lemaitre [Lemaitre, J. 1992. A course on damage mechanics. Springer-Verlag Publishing, Berlin] and proposes to use his model combined with two damage models, a

Leila J. Ladani; Jafar Razmi

2009-01-01

103

Concurrent multi-level model for damage evolution in microstructurally debonding composites  

E-print Network

damage model developed in a preceding paper [Raghavan, P., Ghosh, S., 2005. A continuum damage mechanics) level-0 of pure macroscopic analysis using a continuum damage mechanics (CDM) model; (b) level-1; Continuum damage mechanics 1. Introduction Analysis of composite materials with microstruc- tural

Ghosh, Somnath

104

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

105

Cosmological evolution of Einstein-Aether models with power-law-like potential  

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

106

The discrepancies in multistep damage evolution of yttria-stabilized zirconia irradiated with different ions  

SciTech Connect

This paper reports a comprehensive investigation of structural damage in yttria-stabilized zirconia irradiated with different ions over a wide fluence range. A similar multistep damage accumulation exists for the irradiations of different ions, but the critical doses for occurrence of second damage step, characterized by a faster increase in damage fraction, and the maximum elastic strain at the first damage step are varied and depend on ion mass. For irradiations of heavier ions, the second damage step occurs at a higher dose with a lower critical elastic strain. Furthermore, larger extended defects were observed in the irradiations of heavy ions at the second damage step. Associated with other experiment results and multistep damage accumulation model, the distinct discrepancies in the damage buildup under irradiations of different ions were interpreted by the effects of electronic excitation, energy of primary knock-on atom and chemistry contributions of deposited ions.

Yang, Tengfei [Peking University; Taylor, Caitlin A. [University of Tennessee, Knoxville (UTK); Kong, Shuyan [Peking University; Wang, Chenxu [Peking University; Zhang, Yanwen [ORNL; Huang, Xuejun [Peking University; Xue, Jianming [Peking University; Yan, Sha [Peking University; Wang, Yugang [Peking University

2013-01-01

107

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

108

Rheological Control of Interbedded Siliciclastic Strata on Damage Zone Evolution During Fault Growth  

Microsoft Academic Search

Fault damage zones can have a major impact on fluid flow through sub-surface reservoirs. The typical resolution of seismic reflection data is such that faults with throws 15 m are imaged as discrete planes, revealing none of the smaller scale architecture of the fault damage zones. Previous field studies show that damage zone width scales with fault throw, which suggests

R. H. Wightman; J. Imber; D. Healy; R. E. Holdsworth; K. J. McCaffrey; R. R. Jones

2006-01-01

109

Off-fault damage and acoustic emission distributions during the evolution of structurally complex faults over series of stick-slip events  

NASA Astrophysics Data System (ADS)

Variations in fault structure, for example, surface roughness and deformation zone width, influence the location and dynamics of large earthquakes as well as the distribution of small seismic events. In nature, changes in fault roughness and seismicity characteristics can rarely be studied simultaneously, so that little is known about their interaction and evolution. Here, we investigate the connection between fault structure and near-fault distributions of seismic events over series of stick-slip cycles in the laboratory. We conducted a set of experiments on rough faults that developed from incipient fracture surfaces. We monitored stress and seismic activity which occurred in the form of acoustic emissions (AEs). We determined AE density distributions as a function of fault normal distance based on high-accuracy hypocentre locations during subsequent interslip periods. The characteristics of these distributions were closely connected to different structural units of the faults, that is, the fault core, off-fault and background damage zone. The core deformation zone was characterized by consistently high seismic activity, whereas the off-fault damage zone displayed a power-law decay of seismic activity with increasing distance from the fault core. The exponents of the power-law-distributed off-fault activity increased with successive stick-slip events so that later interslip periods showed a more rapid spatial decay of seismic activity from the fault. The increase in exponents was strongest during the first one to three interslip periods and reached approximately constant values thereafter. The relatively rapid spatial decay of AE events during later interslip periods is likely an expression of decreasing fault zone complexity and roughness. Our results indicate a close relationship between fault structure, stress and seismic off-fault activity. A more extensive mapping of seismic off-fault activity-decay has the potential to significantly advance the understanding of fault zone properties including variations in fault roughness and stress.

Goebel, T. H. W.; Becker, T. W.; Sammis, C. G.; Dresen, G.; Schorlemmer, D.

2014-06-01

110

Geometric evolution law for modeling strongly anisotropic thin-film morphology.  

PubMed

The morphology of the solid-vapor interface of a nanoscale thin crystalline film is influenced by many factors including surface diffusion, attachment-detachment, deposition, and interface kinetics. Using a high-order accurate and efficient numerical method, we investigate the dynamics of two dimensional thin films when all of these effects are considered. The observed morphologies consist of facets of constant slope separated by narrow transition intervals: kinks (valleys) and antikinks (hills). The number of kinks and antikinks decreases as the system coarsens in time. Our numerical results confirm that when deposition is present, the only possible coarsening event is the kink-ternary where two kinks meet and annihilate an antikink. We characterize the total amount of coarsening, the time over which the coarsening occurs and the associated coarsening scaling laws when all effects are considered. As found in previous work that considered only attachment-detachment, or surface diffusion, there are three distinct coarsening regimes associated with increasing magnitudes of the deposition flux-fast coarsening, a regime in which periodic structures form with little or no subsequent coarsening, and a regime in which the film surface evolves chaotically. We find that the inclusion of attachment-detachment leads to additional coarsening compared to the dynamics that result from driven surface diffusion alone. When deposition and interface kinetics are both considered, the slowdown of evolution caused by the kinetic effects necessitates a decrease in the deposition flux in order to produce a nonchaotic coarsening regime. Together, these provide testable predictions for experiments of thin-film dynamics. PMID:22304101

Ograin, Christopher; Lowengrub, John

2011-12-01

111

Effect of ageing in fibre bundle models on the evolution of acoustic and silent damage in time-dependent failure  

NASA Astrophysics Data System (ADS)

The spatio-temporal evolution of damage in brittle materials is often modelled by fibre bundle models. In real fibre bundles (such as suspension bridge ropes), and in other composite materials such as rocks and ceramics, the evolution of damage as a function of stress and time can be recorded using acoustic emissions (AE), and used to asses the integrity of the sample and its lifetime. Such monitoring however tells only part of the story, since time-dependent, effectively 'silent' damage also occurs without AE, and small AE events may not be recorded below some recording threshold set by the background noise. The proportion of seismic to aseismic deformation is important for a number of applications, for example providing a strong constraint on plate boundary dynamics and estimates of earthquake hazard. Accordingly we have modified the usual fibre bundle model by introducing some additional ageing, which results in silent damage below a nominal threshold for more dynamic deformation. This enables us to model the effect of the model parameters on the ratio of acoustic to total damage, and how it evolves in time under a given stress history. We found that the silent damage dominates the process and that for a constant applied stress the ratio between acoustic and silent emissions is approximately constant over a wide range of time. The proportionality factor depends strongly on the applied stress and only weakly on the ageing parameter, while it is the other way around for the failure time which depends more on the ageing parameter than on the applied stress.

Lennartz, S.; Main, I. G.; Zaiser, M.; Kun, F.

2012-04-01

112

Constraining the stream power law: a novel approach combining a landscape evolution model and an inversion method  

NASA Astrophysics Data System (ADS)

In the past few decades, many studies have been dedicated to the understanding of the interactions between tectonics and erosion, in many instances through the use of numerical models of landscape evolution. Among the numerous parameterizations that have been developed to predict river channel evolution, the stream power law, which links erosion rate to drainage area and slope, remains the most widely used. Despite its simple formulation, its power lies in its capacity to reproduce many of the characteristic features of natural systems (the concavity of river profile, the propagation of knickpoints, etc.). However, the three main coefficients that are needed to relate erosion rate to slope and drainage area in the stream power law remain poorly constrained. In this study, we present a novel approach to constrain the stream power law coefficients under the detachment-limited mode by combining a highly efficient landscape evolution model, FastScape, which solves the stream power law under arbitrary geometries and boundary conditions and an inversion algorithm, the neighborhood algorithm. A misfit function is built by comparing topographic data of a reference landscape supposedly at steady state and the same landscape subject to both uplift and erosion over one time step. By applying the method to a synthetic landscape, we show that different landscape characteristics can be retrieved, such as the concavity of river profiles and the steepness index. When applied on a real catchment (in the Whataroa region of the South Island in New Zealand), this approach provides well-resolved constraints on the concavity of river profiles and the distribution of uplift as a function of distance to the Alpine Fault, the main active structure in the area.

Croissant, T.; Braun, J.

2014-03-01

113

Constraining the Stream Power Law: a novel approach combining a Landscape Evolution Model and an inversion method  

NASA Astrophysics Data System (ADS)

In the past few decades, many studies have been dedicated to our understanding of the interactions between tectonic and erosion and, in many instances, using numerical models of landscape evolution. Among the numerous parameterizations that have been developed to predict river channel evolution, the Stream Power Law, which links erosion rate to drainage area and slope, remains the most widely used. Despite its simple formulation, its power lies in its capacity to reproduce many of the characteristic features of natural systems (the concavity of river profile, the propagation of knickpoints, etc.). However, the three main coefficients that are needed to relate erosion rate to slope and drainage area in the Stream Power Law remain poorly constrained. In this study, we present a novel approach to constrain the Stream Power Law coefficients under the detachment limited mode by combining a highly efficient Landscape Evolution Model, FastScape, which solves the Stream Power Law under arbitrary geometries and boundary conditions and an inversion algorithm, the Neighborhood Algorithm. A misfit function is built by comparing topographic data of a reference landscape supposedly at steady state and the same landscape subject to both uplift and erosion over one time step. By applying the method to a synthetic landscape, we show that different landscape characteristics can be retrieved, such as the concavity of river profiles and the steepness index. When applied on a real catchment (in the Whataroa region of the South Island in New Zealand), this approach provide well resolved constraints on the concavity of river profiles and the distribution of uplift as a function of distance to the Alpine Fault, the main active structure in the area.

Croissant, T.; Braun, J.

2013-11-01

114

Time evolution of electric fields and currents and the generalized Ohm's law  

Microsoft Academic Search

Fundamentally, the time derivative of the electric field is given by the displacement-current term in Maxwell's generalization of Ampère's law, and the time derivative of the electric current density is given by the generalized Ohm's law. The latter is derived by summing the accelerations of all the plasma particles and can be written exactly, with no approximations, in a (relatively

V. M. Vasyliunas

2005-01-01

115

EVALUATION OF DAMAGE EVOLUTION UNDER REPEATED LOADING OF POST-TENSIONED CONCRETE BEAMS BY ACOUSTIC EMISSION  

Microsoft Academic Search

Recent collapses of bridges have demonstrated once again the need for reliable tools for an early monitoring of damage progression. Damages due to deterioration processes, overload, bad design, poor material quality, can grow subcritically until final collapse of the structure. AE method has been successful used for more than 20 years in industry for monitoring metal equipments (pipelines, pressure vessels,

Edoardo Proverbio; Giuseppe Campanella; Vincenzo Venturi

116

Host Galaxy Extinction of SNIa: Co-evolution of ISM Structure and Extinction Law with Star-Formation  

E-print Network

This paper presents a mechanism that may modify the extinction law for SNIa observed at higher redshift. Starting from the observations that (1) SNIa occur predominantly in spiral galaxies, (2) star-formation ejects ISM out of the plane of spirals, (3) star-formation alters the extinction properties of the dust in the ISM, and (4) there is substantially more star-formation at higher redshift, I propose that spiral galaxies have a dustier halo in the past than they do now. The ejected material's lower value of $R_V$ will lead to a lower average value ($\\bar{R}_V$) for SNIa observed at higher redshift. Two relations in SNIa observations indicate evolution of the average $R_V$: the relation of observed $R_V$ with inclination of the host galaxy at low redshift and the matching of the distribution of extinction values ($A_V$) for SNIa in different redshift intervals. The inclination effect does point to a halo with lower $R_V$ values. In contrast, the distributions of $A_V$ values match best for a $\\bar{R}_V(z)$ evolution that mimics the relation of SNIa dimming with redshift attributed to the cosmological constant. However, even in the worse case scenario, the evolution $\\bar{R}_V$ can not fully explain the dimming of SNIa: host galaxy extinction law evolution is not a viable alternative to account for the dimming of SNIa. Future observations of SNIa --multi-color lightcurves and spectra-- will solve separately for values of $A_V$ and $R_V$ for each SNIa . Solving for evolution of $\\bar{R}_V$ (and $A_V$) with redshift will be important for the coming generation of cosmological SNIa measurements and has the bonus science of insight into the distribution of dust-rich ISM in the host galaxies in the distant past.

B. W. Holwerda

2008-01-31

117

Evolution of a hairpin vortex in a shear-thinning fluid governed by a power-law model  

NASA Astrophysics Data System (ADS)

The effect of a shear-thinning fluid governed by a power-law model on the evolution of a hairpin vortex in a wall-bounded flow was studied by means of direct numerical simulation. With a fixed Reynolds number and hairpin vortex strength, the effect of shear-thinning on vortex evolution could be isolated. The primary observation is that very early in time shear-thinning has the effect of reducing the production of vortex kinetic energy and dramatically increasing viscous dissipation. This leads to a delay in the transition of the flow to a turbulent state. Three-dimensional flow visualizations reveal that the increased dissipation is associated with an instability in which the hairpin vortex is broken down into small-scale structures. It is suggested that the finite amplitude of the hairpin creates a lowering of viscosity near the hairpin vortex core which leads to this instability.

Zhen, Ni; Handler, Robert A.; Zhang, Qi; Oeth, Cassandra

2013-10-01

118

A model for predicting the evolution of damage in the plastic bonded explosive LX17  

E-print Network

. . . . . Figure 9: An Idealized Representative Volume of a Damaged Zone. . . . . . . . . Figure 10: Single Fibril Traction and Displacement Components . . . . . . . . . . . . . Figure 11: Defining Area Averaged Traction in a Damaged Zone RVE . . . Figure 12...-established concept. In fracture mechanics, cohesive zones refer to areas ahead of crack tips where non-zero tractions have been specified in such a manner as to inhibit crack tip advancement. Dugdale (1960) and Barenblatt (1962) were the first to propose the use...

Seidel, Gary Don

2002-01-01

119

DNA repair and the evolution of transformation in Bacillus subtilis. 3. Sex with damaged DNA  

SciTech Connect

Natural genetic transformation in the bacterium Bacillus subtilis provides an experimental system for studying the evolutionary function of sexual recombination. The repair hypothesis proposes that during transformation the exogenous DNA taken up by cells is used as template for recombinational repair of damages in the recipient cell's genome. Earlier results demonstrated that the population density of transformed cells (i.e., sexual cells) increases, relative to nontransformed cells (primarily asexual cells), with increasing dosage of ultraviolet irradiation, provided that the cells are transformed with undamaged homologous DNA after they have become damaged. In nature, however, donor DNA for transformation is likely to come from cells that are as damaged as the recipient cells. In order to better simulate the effects of transformation in natural populations we conducted similar experiments as those just described using damaged donor DNA. The authors document in this report that transformants continue to increase in relative density even if they are transformed with damaged donor DNA. These results suggest that sites of transformation are often damaged sites in the recipient cell's genome.

Hoelzer, M.A.; Michod, R.E. (Department of Ecology and Evolutionary Biology, University of Arizona, Tucson (USA))

1991-06-01

120

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

121

Comparing monofractal and multifractal analysis of corrosion damage evolution in reinforcing bars.  

PubMed

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

122

Helicopter rotor blade frequency evolution with damage growth and signal processing  

NASA Astrophysics Data System (ADS)

Structural damage in materials evolves over time due to growth of fatigue cracks in homogenous materials and a complicated process of matrix cracking, delamination, fiber breakage and fiber matrix debonding in composite materials. In this study, a finite element model of the helicopter rotor blade is used to analyze the effect of damage growth on the modal frequencies in a qualitative manner. Phenomenological models of material degradation for homogenous and composite materials are used. Results show that damage can be detected by monitoring changes in lower as well as higher mode flap (out-of-plane bending), lag (in-plane bending) and torsion rotating frequencies, especially for composite materials where the onset of the last stage of damage of fiber breakage is most critical. Curve fits are also proposed for mathematical modeling of the relationship between rotating frequencies and cycles. Finally, since operational data are noisy and also contaminated with outliers, denoising algorithms based on recursive median filters and radial basis function neural networks and wavelets are studied and compared with a moving average filter using simulated data for improved health-monitoring application. A novel recursive median filter is designed using integer programming through genetic algorithm and is found to have comparable performance to neural networks with much less complexity and is better than wavelet denoising for outlier removal. This filter is proposed as a tool for denoising time series of damage indicators.

Roy, Niranjan; Ganguli, Ranjan

2005-05-01

123

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

NASA Technical Reports Server (NTRS)

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(8), 90(8), and +/- 45(2s) line oriented 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.; Newaz, G. M.; Ellis, J. R.

1993-01-01

124

Menzerath-Altmann law in mammalian exons reflects the dynamics of gene structure evolution.  

PubMed

Genomic sequences exhibit self-organization properties at various hierarchical levels. One such is the gene structure of higher eukaryotes with its complex exon/intron arrangement. Exon sizes and exon numbers in genes have been shown to conform to a law derived from statistical linguistics and formulated by Menzerath and Altmann, according to which the mean size of the constituents of an entity is inversely related to the number of these constituents. We herein perform a detailed analysis of this property in the complete exon set of the mouse genome in correlation to the sequence conservation of each exon and the transcriptional complexity of each gene locus. We show that extensive linear fits, representative of accordance to Menzerath-Altmann law are restricted to a particular subset of genes that are formed by exons under low or intermediate sequence constraints and have a small number of alternative transcripts. Based on this observation we propose a hypothesis for the law of Menzerath-Altmann in mammalian genes being predominantly due to genes that are more versatile in function and thus, more prone to undergo changes in their structure. To this end we demonstrate one test case where gene categories of different functionality also show differences in the extent of conformity to Menzerath-Altmann law. PMID:25155263

Nikolaou, Christoforos

2014-12-01

125

The Evolution of Criminal Law and Police during the Pre-modern Era  

Microsoft Academic Search

Increased standardization was a by-product of technical innovations during the Industrial Revolution. An unfortunate side effect of standardization was enhanced opportunities for theft and embezzlement. Two significant modern institutions radically evolved during the eighteenth to mid-nineteenth centuries to control these growing problems: criminal law and public police. These institutions strongly interacted with the pace of the Industrial Revolution. Our argument

Douglas W. Allen; Yoram Barzel

2009-01-01

126

A computational model for predicting damage evolution in laminated composite plates  

E-print Network

The feasibility of producing a model capable of predicting the evolution of interface degradation, matrix cracking, and delimitation at multiple sites in laminated continuous fiber composite plates subjected to monotonic loading, while still being...

Phillips, Mark Lane

1999-01-01

127

The Source of Alabama’s Abundance of Arbitration Cases: Alabama’s 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

128

Finite volume evolution Galerkin method for hyperbolic conservation laws with spatially varying flux functions  

NASA Astrophysics Data System (ADS)

We present a generalization of the finite volume evolution Galerkin scheme [M. Luká?ová-Medvid'ová, J. Saibertov'a, G. Warnecke, Finite volume evolution Galerkin methods for nonlinear hyperbolic systems, J. Comp. Phys. (2002) 183 533- 562; M. Luká?ová-Medvid'ová, K.W. Morton, G. Warnecke, Finite volume evolution Galerkin (FVEG) methods for hyperbolic problems, SIAM J. Sci. Comput. (2004) 26 1-30] for hyperbolic systems with spatially varying flux functions. Our goal is to develop a genuinely multi-dimensional numerical scheme for wave propagation problems in a heterogeneous media. We illustrate our methodology for acoustic waves in a heterogeneous medium but the results can be generalized to more complex systems. The finite volume evolution Galerkin (FVEG) method is a predictor-corrector method combining the finite volume corrector step with the evolutionary predictor step. In order to evolve fluxes along the cell interfaces we use multi-dimensional approximate evolution operator. The latter is constructed using the theory of bicharacteristics under the assumption of spatially dependent wave speeds. To approximate heterogeneous medium a staggered grid approach is used. Several numerical experiments for wave propagation with continuous as well as discontinuous wave speeds confirm the robustness and reliability of the new FVEG scheme.

Arun, K. R.; Kraft, M.; Luká?ová-Medvid'ová, M.; Prasad, Phoolan

2009-02-01

129

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.

130

Patterns of evolution of myocyte damage after human heart transplantation detected by indium-111 monoclonal antimyosin  

Microsoft Academic Search

The indium-111 labeled Fab fragment of antimyosin monoclonal antibody was used to study cardiac rejection and the time course of myocyte damage after transplantation. Fifty-three studies were performed in 21 patients, 17 men and 4 women, aged 19 to 54 years (mean 37 +\\/- 8), from 7 to 40 months after transplantation. Repeat studies were available in 8, and 10

M. Ballester-Rodes; I. Carrio-Gasset; L. Abadal-Berini; D. Obrador-Mayol; L. Berna-Roqueta; J. M. Caralps-Riera

1988-01-01

131

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

132

Some New Integrable Nonlinear Evolution Equations and Their Infinitely Many Conservation Laws  

Microsoft Academic Search

A hierarchy of new nonlinear evolution equations associated with a 3×3 matrix spectral problem with two potentials is derived and its Hamiltonian structures are established with the aid of trace identity. The negative flow of the hierarchy is then discussed. A reduction of this hierarchy and its Hamiltonian structures are constructed. An infinite sequence of conserved quantities of several new

Xianguo Geng; Bo Xue

2010-01-01

133

Dictyostelium discoideum, a lower eukaryote model for the study of DNA repair: Implications for the role of DNA-damaging chemicals in the evolution of repair proficient cells  

NASA Astrophysics Data System (ADS)

The evolution of the ability of living cells to cope with stress is crucial for the maintenance of their genetic integrity. Yet low levels of mutation must remain to allow adaptation to environmental changes. The cellular slime mold D. discoideum is a good system for studying molecular aspects of the repair of lethal and mutagenic damage to DNA by radiation and chemicals. The wild-type strains of this soil microorganism are extremely resistant to DNA damaging agents. In nature the amoeboid cells in their replicative stage feed on soil bacteria and are exposed to numerous DNA-damaging chemicals produced by various soil microorganisms. It is probable that the evolution of repair systems in this organism and perhaps in others is a consequence of the necessity to cope with chemical damage which also confers resistance to radiation.

Deering, R. A.

1994-10-01

134

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

135

Contact behavior evolution induced by damage growth in radio-frequency microelectromechanical system switches  

NASA Astrophysics Data System (ADS)

This study provides a two-contact-event model to explain the evolution of the contact behavior of microelectromechanical system (MEMS) switches through their lifetime. The succession of two dynamic contact events is carefully considered during actuation inspired by experimental observations. The contact between the MEMS switch tip and the drain can be treated as an effective contact between an elastic hemisphere and a rigid plane. If the first contact event results in elastic deformation, the effective hemisphere will fully recover. Consequently, the subsequent contact event also produces elastic deformation. If, on the other hand, the first contact event induces elastoplastic or plastic deformation, a residual depth will be produced between the hemisphere and the rigid plane. The contact force of the subsequent contact event can be significantly reduced due to this additional residual depth. With the growth of residual depth during the switch cycling process, the modeling results show three possible situations of contact radius evolution: (1) The contact radius increases to a maximum value and then decreases to zero; (2) the contact radius increases to one local maximum value; then decreases to a local minimum value; subsequently increases again to another maximum value, and finally decreases to zero; and (3) the contact radius increases to one maximum value and then decreases to zero; after an intermittent response, the contact radius increases again to another maximum value and finally decreases to zero. Furthermore, the Maxwell spreading formula is applied to determine the contact resistance which is inversely proportional to the contact radius. Three situations of contact resistance evolution corresponding to the evolution of contact radius are obtained. All three situations are also observed and validated by the experimental results.

Wu, Y.; Peroulis, D.

2015-02-01

136

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

137

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 . 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

2015-03-01

138

Patterns of evolution of myocyte damage after human heart transplantation detected by indium-111 monoclonal antimyosin  

SciTech Connect

The indium-111 labeled Fab fragment of antimyosin monoclonal antibody was used to study cardiac rejection and the time course of myocyte damage after transplantation. Fifty-three studies were performed in 21 patients, 17 men and 4 women, aged 19 to 54 years (mean 37 +/- 8), from 7 to 40 months after transplantation. Repeat studies were available in 8, and 10 were studied after the first year of transplantation. A heart-to-lung ratio was used for quantitation of uptake (normal 1.46 +/- 0.04). Differences between absent (1.69 +/- 0.29) and moderate (1.90 +/- 0.36) rejection were significant (p less than 0.03). Antimyosin ratio at 1 to 3 months (1.89 +/- 0.35) differed from that at greater than 12 months (1.65 +/- 0.2) (p less than 0.01). Repeat studies revealed a decrease in antimyosin ratio in 5 patients with uneventful clinical course; 2 had persistent activity after transplantation and suffered heart failure from rejection. After 1 year of transplantation uptake was within normal limits in 7 of 10 patients, and high uptake was associated with vascular rejection in 1. Because they can define evolving patterns of myocardial lesion activity, antimyosin studies could be useful both in patient management and in concentrating resources for those patients who most require them. The heart-to-lung ratio is suggested to monitor sequentially the degree of myocyte damage after transplantation.

Ballester-Rodes, M.; Carrio-Gasset, I.; Abadal-Berini, L.; Obrador-Mayol, D.; Berna-Roqueta, L.; Caralps-Riera, J.M.

1988-09-15

139

Constraining the Stream Power Law: a novel approach combining a Landscape Evolution Model and an inversion method  

NASA Astrophysics Data System (ADS)

In the past few decades, many studies have been dedicated to our understanding of the interactions between tectonics and erosion. To predict river channel evolution, the Stream Power Law (SPL), which links erosion rate to drainage area and slope (E = KAmSn), remains the most widely used erosion model in the community. Despite its simple formulation, its power lies in its capacity to reproduce many of the characteristic features of natural systems (the concavity of river profile, the propagation of knickpoints, etc.). However, the three main coefficients that are needed to relate erosion rate to slope and drainage area in the SPL remain poorly constrained. In this study, we present a novel approach to constrain the SPL coefficients under the detachment limited mode by combining a highly efficient Landscape Evolution Model, FastScape and an inversion algorithm, the Neighborhood Algorithm. A misfit function is built by comparing topographic data of a reference landscape supposedly at steady state and the same landscape subject to both uplift and erosion over one time step. By applying the method to a synthetic landscape, we show that different landscape characteristics can be retrieved, such as the concavity of river profiles and the steepness index. When applied on a real catchment (in the Whataroa region of the South Island in New Zealand), this approach provides well resolved constraints on the concavity of river profiles and the distribution of uplift as a function of distance to the Alpine Fault, the main active structure in the area.

Croissant, Thomas; Braun, Jean

2014-05-01

140

Dynamic damage model of crevasse opening and application to glacier calving  

NASA Astrophysics Data System (ADS)

Theory and applications of continuum damage mechanics for ice are discussed, and on this basis, an ice damage model, valid at low stresses, is proposed. The model describes the damage itself, the rheology of the damaged ice, and the damage evolution. A local damaging and healing law is considered, and its parameterization is motivated. The model parameters are inferred from published data of laboratory experiments. The model is subsequently implemented in a finite element code and applied to the prediction of a calving process and to the destabilization of an ice chunk from a hanging glacier. Numerical results show good agreement with field measurements.

Pralong, A.; Funk, M.

2005-01-01

141

An explicit finite element formulation for dynamic strain localization and damage evolution in metals  

SciTech Connect

An explicit finite element formulation, used to study the behavior and failure mechanisms of metallic materials under high strain rate loading, is presented. The formulation is based on the assumed-strain approach of Fish and Belytschko [1988], which allows localization bands to be embedded within an element, thereby alleviating mesh sensitivity and reducing the required computational effort. The behavior of the material outside localization bands (and of the virgin material prior to the onset of strain localization) is represented using a Gurson-type coupled plasticity-damage model based on the work of Johnson and Addessio [1988]. Assuming adiabatic conditions, the response of the localization band material is represented by a set of constitutive equations for large elasticviscoplastic deformations in metals at high strain rates and high homologous temperatures (see Brown et al. [1989]). Computational results are compared to experimental data for different metallic alloys to illustrate the advantages of the proposed modeling strategy.

Mourad, Hashem M [Los Alamos National Laboratory; Bronkhorst, Curt A [Los Alamos National Laboratory; Addessio, Francis L [Los Alamos National Laboratory

2010-12-16

142

The spatial-temporal evolution of coherent structures in log law region of turbulent boundary layer  

NASA Astrophysics Data System (ADS)

The spatial-temporal evolution of coherent structures (CS) is significant for turbulence control and drag reduction. Among the CS, low and high speed streak structures show typical burst phenomena. The analysis was based on a time series of three-dimensional and three-component (3D-3C) velocity fields of the flat plate turbulent boundary layer (TBL) measured by a Tomographic and Time-resolved PIV (Tomo TRPIV) system. Using multi-resolution wavelet transform and conditional sampling method, we extracted the intrinsic topologies and found that the streak structures appear in bar-like patterns. Furthermore, we seized locations and velocity information of transient CS, and then calculated the propagation velocity of CS based on spatial-temporal cross-correlation scanning. This laid a foundation for further studies on relevant dynamics properties.

Zheng, Xiao-Bo; Jiang, Nan

2015-02-01

143

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

144

Law by human intent or evolution? Some remarks on the Austrian school of economics’ role in the development of law and economics  

Microsoft Academic Search

In the late nineteenth century, economic analysis of law experienced an outright rejection by the German-speaking legal community.\\u000a In the second half of the twentieth century, it became a dominant approach in American legal inquiry. We argue that this success\\u000a was partly due to the insights of Austrian economics which the second wave of law and economics has incorporated. We

Michael Litschka; Kristoffel Grechenig

2010-01-01

145

Genetic Basis of a Violation of Dollo’s Law: Re-Evolution of Rotating Sex Combs in Drosophila bipectinata  

PubMed Central

Phylogenetic analyses suggest that violations of “Dollo’s law”—that is, re-evolution of lost complex structures—do occur, albeit infrequently. However, the genetic basis of such reversals has not been examined. Here, we address this question using the Drosophila sex comb, a recently evolved, male-specific morphological structure composed of modified bristles. In some species, sex comb development involves only the modification of individual bristles, while other species have more complex “rotated” sex combs that are shaped by coordinated migration of epithelial tissues. Rotated sex combs were lost in the ananassae species subgroup and subsequently re-evolved, ?12 million years later, in Drosophila bipectinata and its sibling species. We examine the genetic basis of the differences in sex comb morphology between D. bipectinata and D. malerkotliana, a closely related species with a much simpler sex comb representing the ancestral condition. QTL mapping reveals that >50% of this difference is controlled by one chromosomal inversion that covers ?5% of the genome. Several other, larger inversions do not contribute appreciably to the phenotype. This genetic architecture suggests that rotating sex combs may have re-evolved through changes in relatively few genes. We discuss potential developmental mechanisms that may allow lost complex structures to be regained. PMID:23086218

Seher, Thaddeus D.; Ng, Chen Siang; Signor, Sarah A.; Podlaha, Ondrej; Barmina, Olga; Kopp, Artyom

2012-01-01

146

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

147

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

148

Yearly evolution of organ damage markers in diabetes or metabolic syndrome: data from the LOD-DIABETES study  

PubMed Central

Background Cardiovascular disease morbidity-mortality is greater in people with type 2 diabetes mellitus or metabolic syndrome. The purpose of this study was to evaluate the yearly evolution of organ damage markers in diabetes or metabolic syndrome, and to analyze the associated factors. Methods An observational prospective study was carried out in the primary care setting, involving 112 patients: 68 diabetics and 44 subjects with metabolic syndrome, subjected to 12 months of follow-up. Measurements: traditional cardiovascular risk factors (blood pressure, blood glucose, lipids, smoking, body mass index (BMI) and) and non-traditional risk factors (waist circumference, hsC Reactive Protein and fibrinogen); subclinical vascular (carotid intima-media thickness, pulse wave velocity and ankle/brachial index), cardiac (Cornell voltage-duration product), renal organ damage (creatinine, glomerular filtration and albumin/creatinine index), and antihypertensive and lipid-lowering drugs. Results At baseline, the diabetics presented a mean age of 59.9 years, versus 55.2 years in the subjects with metabolic syndrome (p = 0.03). Diastolic blood pressure, total cholesterol and HDL-cholesterol were lower among the patients with diabetes, while blood glucose and HbA1c, as well as antihypertensive and lipid-lowering drug use, were greater. At evaluation after one year, the diabetics showed a decrease in BMI (-0.39), diastolic blood pressure (-3.59), and an increase in fibrinogen (30.23 mg/dL), ankle/brachial index (0.07) and the number of patients with ankle/brachial index pathologic decreased in 6. In turn, the patients with metabolic syndrome showed an increase in HDL-cholesterol (1-91 mg/dL), fibrinogen (25.54 mg/dL), Cornell voltage-duration product (184.22 mm/ms), ankle/brachial index (0.05) and the use of antihypertensive and lipid-lowering drugs, and a reduction in serum glucose (3.74 mg/dL), HOMA, systolic (-6.76 mmHg), diastolic blood pressure (-3.29 mmHg), and pulse wave velocity (-0.72 m/s). The variable that best predicted a decrease in pulse wave velocity in subjects with metabolic syndrome was seen to be an increase in antihypertensive drug use. Conclusions The annual assessment of cardiovascular risk factors and the decrease in pulse wave velocity was more favorable in the patients with metabolic syndrome, probably influenced by the increased percentage of subjects treated with antihypertensive and lipid lowering drugs in this group. PMID:21999369

2011-01-01

149

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

150

Material response to shock/dynamic loading: Windows into kinetic and stress-state effects on defect generation and damage evolution  

NASA Astrophysics Data System (ADS)

While the field of shock-wave physics has provided significant insights into many of the processes related to wave propagation in materials, the exact operative micromechanisms of defect generation occurring during the shock and thereafter those controlling defect storage and damage evolution remain incompletely understood and poorly modeled. Attainment of a truly predictive capability to enable accurate simulations of dynamic impact, shock, and high-rate loading phenomena applications requires a linked experimental, modeling, and validation research program. In this talk an overview of the microstructural mechanisms affecting the strength of materials at high pressure and strain rates as well as the processes controlling damage evolution during shock loading will be reviewed. The spectrum of physical phenomena and the potential nation-wide experimental facilities poised to study them is discussed. In addition, the limitations and caveats involved in using only velocimetry, single-pass radiography, and/or shock recovery alone to elucidate the 3-D aspects of defect generation, storage, and recovery will be examined in detail. Examples of how both "real-time" and post-mortem experimental approaches are needed to quantify dislocation / defect generation, shock-induced phase transitions, and damage evolution and spallation will be discussed.

Gray, George Thompson, III

2012-03-01

151

Ankle skeletal injury predictions using anisotropic inelastic constitutive model of cortical bone taking into account damage evolution.  

PubMed

The most severe ankle skeletal injury called pilon fractures can cause long term disability and impairment. Based on previous experimental studies, the pilon fractures are regarded as caused by a high-energy compressive force in the ankle joint and affected by a muscular tension force generated by emergency braking. However, quantitative injury criteria for the pilon fractures are still unknown. More accurate prediction of bone fractures in the distal tibia using a FE model of human lower leg can help us know the quantitative injury criteria. Therefore we newly proposed an anisotropic inelastic constitutive model of cortical bone including damage evolution and then implemented it to a FE code, LS-DYNA. The proposed model successfully reproduced most of anisotropy, strain rate dependency, and asymmetry of tension and compression on material and failure properties of human femoral cortical bone. However, the simplified model using an isotropic elasto-viscoplastic material, which has been used in previous studies, did not reproduce the characteristic features of the cortical bone. Two series of validation on axial impact cadaver tests for the foot and ankle indicate that the proposed model predicts the pilon fractures more accurately than the simplified model. Parametric studies on footwell impacts and pedal impacts for the foot using the proposed model show that the severity of the pilon fractures increases when the foot sustains normal and heel impacts with the impact velocity of 5 m/s and the pedal hits the forefoot with the impact velocity of 3 m/s regardless of the muscular tension force. PMID:17096272

Iwamoto, Masami; Miki, Kazuo; Tanaka, Eiichi

2005-11-01

152

Transboundary Damage in International Law  

Microsoft Academic Search

The Chernobyl disaster, the Amoco Cadiz oil spill and the Colorado River dispute are examples of an activity conducted by one State which has serious adverse effects in the territory of another, or in global common areas. This book details the international rules and compensation procedures, and is intended for use by governmental officials, international lawyers and jurists. It discusses

Xue Hanqin

153

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

154

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 form—the celebrated “Laws of Form”—was seen as one of the major tasks

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

2002-01-01

155

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

156

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

157

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

158

Characterizing Damage Evolution and Yield in Sandstone Under Triaxial Loading as a Function of Various Effective Pressure  

E-print Network

, 20, and 30 MPa, and confining pressures of 50, 180, and 260 MPa to investigate the brittle, transitional, and ductile regimes. Measurement of sample strain and acoustic emissions are used to quantify the accumulation of damage and map equivalent...

Choens II, Robert C.

2011-02-22

159

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

160

Microstructure evolution of hot-work tool steels during tempering and definition of a kinetic law based on hardness measurements  

Microsoft Academic Search

Microstructural evolutions of the 55NiCrMoV7 steel during tempering were investigated by transmission electron microscopy, scanning electron microscopy and X-ray diffraction in order to describe the main mechanisms of softening. The softening resistance is strongly associated with evolution of obstacles to the movement of dislocations (prior austenitic grain boundary, lath boundary, secondary carbides, etc.). Only the average size of carbides was

Z Zhang; D Delagnes; G Bernhart

2004-01-01

161

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

162

A theoretical model to study the effects of cellular stiffening on the damage evolution in deep tissue injury  

Microsoft Academic Search

Pressure induced deep tissue injury (DTI) is a severe form of pressure ulcers that is hard to detect in early stages and difficult to prevent and treat. High prevalence figures are partly due to a lack of understanding of pathological pathways involved in DTI. The aim of this study was to investigate, whether changes in material properties of damaged tissue

T. Nagel; S. Loerakker; C. W. J. Oomens

2009-01-01

163

Investigation of a Novel NDE Method for Monitoring Thermomechanical Damage and Microstructure Evolution in Ferritic-Martensitic Steels for Generation IV Nuclear Energy Systems  

SciTech Connect

The main goal of the proposed project is the development of validated nondestructive evaluation (NDE) techniques for in situ monitoring of ferritic-martensitic steels like Grade 91 9Cr-1Mo, which are candidate materials for Generation IV nuclear energy structural components operating at temperatures up to ~650{degree}C and for steam-generator tubing for sodium-cooled fast reactors. Full assessment of thermomechanical damage requires a clear separation between thermally activated microstructural evolution and creep damage caused by simultaneous mechanical stress. Creep damage can be classified as "negligible" creep without significant plastic strain and "ordinary" creep of the primary, secondary, and tertiary kind that is accompanied by significant plastic deformation and/or cavity nucleation and growth. Under negligible creep conditions of interest in this project, minimal or no plastic strain occurs, and the accumulation of creep damage does not significantly reduce the fatigue life of a structural component so that low-temperature design rules, such as the ASME Section III, Subsection NB, can be applied with confidence. The proposed research project will utilize a multifaceted approach in which the feasibility of electrical conductivity and thermo-electric monitoring methods is researched and coupled with detailed post-thermal/creep exposure characterization of microstructural changes and damage processes using state-of-the-art electron microscopy techniques, with the aim of establishing the most effective nondestructive materials evaluation technique for particular degradation modes in high-temperature alloys that are candidates for use in the Next Generation Nuclear Plant (NGNP) as well as providing the necessary mechanism-based underpinnings for relating the two. Only techniques suitable for practical application in situ will be considered. As the project evolves and results accumulate, we will also study the use of this technique for monitoring other GEN IV materials. Through the results obtained from this integrated materials behavior and NDE study, new insight will be gained into the best nondestructive creep and microstructure monitoring methods for the particular mechanisms identified in these materials. The proposed project includes collaboration with a national laboratory partner and the results will also serve as a foundation to guide the efforts of scientists in the DOE laboratory, university, and industrial communities concerned with the technological challenges of monitoring creep and microstructural evolution in materials planned to be used in Generation IV Nuclear Energy Systems.

Nagy, Peter

2013-09-30

164

Heavy-ion irradiations of Fe and Fe-Cr model alloys, part 1: damage evolution in thin-foils at lower doses.  

SciTech Connect

The evolution of radiation damage in Fe and Fe-Cr alloys under heavy-ion irradiation was investigated using transmission electron microscopy. Thin foils were irradiated with 100 or 150 keV Fe{sup +} and Xe{sup +} ions at room temperature (RT) and 300 C. Dynamic observations followed the evolution of damage and the early stages in damage development are reported. Small (2-5 nm) dislocation loops first appeared at doses between 10{sup 16} and 10{sup 17} ions m{sup -2} in all materials. Loop number densities depended strongly on the foil orientation in pure Fe but not in Fe-Cr alloys. Number densities did not depend strongly on Cr content. For a given material, defect yields were higher for Xe{sup +} ions than for Fe{sup +} ions, and were higher at RT than at 300 C. Loops with both 100 and 1/2 111 Burgers vectors were identified. The proportion of 100 loops was larger, especially in pure Fe. Dynamic observations showed that: the contrast of some new loops developed over intervals as long as 0.2 s; hopping of 1/2 111 loops was induced by the ion and electron beams and was pronounced in ultra-pure iron; and many loops were lost during and after ion irradiation by glide to the foil surface. The number of loops retained was strongly dependent on the foil orientation in Fe, but less so in Fe-Cr alloys. This is due to lower loop mobility in Fe-Cr alloys, probably due to pinning by Cr atoms. Reduced loop loss probably explains the higher loop number densities in Fe-Cr alloys compared with pure Fe.

Yao, Z.; Hernandez-Mayoral, M.; Jenkins, M. L.; Kirk, M. A.; Univ. Oxford; CIEMAT Avendia Complutense

2008-07-31

165

Laws of Physical Laws  

Microsoft Academic Search

Statements about scientific laws, called metanomological statements, are examined. The following kinds are distinguished and illustrated: (1) factual metanomological statements like ``Newton's laws of motion are invariant under time reversal`` (2) normative metanomological statements such as ``The equations of motion are not to depend on any frame of reference'' and (3) methodological metanomological statements like ``Law statements should not include

Mario Bunge

1961-01-01

166

In-Situ Monitoring of Damage Evolution in Glass Matrix Composites during Cyclic Loading using Nondestructive Techniques  

NASA Astrophysics Data System (ADS)

Infrared thermography is a powerful non-destructive testing technique which can be used for the detection of damage in advanced materials such as ceramic matrix composites. The purpose of this study is to apply a non-destructive methodology for analyzing, in real-time, the thermal effects in ceramic matrix composites caused by cyclic loading. Mechanical stresses induced by cyclic loading cause heat release in the composite due to failure of the interface, which results in increasing the material’s temperature. The heat waves, generated by the thermo-mechanical coupling, and the intrinsic energy dissipated during mechanical cyclic loading of the specimen, were detected by an infrared camera. The results were correlated with acoustic emission events that occurred during the damage accumulation process of the material.

Kordatos, E. Z.; Aggelis, D. G.; Dassios, K. G.; Matikas, T. E.

2013-10-01

167

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

168

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

169

Temperature activated absorption during laser-induced damage: The evolution of laser-supported solid-state absorption fronts  

SciTech Connect

Previously we have shown that the size of laser induced damage sites in both KDP and SiO{sub 2} is largely governed by the duration of the laser pulse which creates them. Here we present a model based on experiment and simulation that accounts for this behavior. Specifically, we show that solid-state laser-supported absorption fronts are generated during a damage event and that these fronts propagate at constant velocities for laser intensities up to 4 GW/cm{sup 2}. It is the constant absorption front velocity that leads to the dependence of laser damage site size on pulse duration. We show that these absorption fronts are driven principally by the temperature-activated deep sub band-gap optical absorptivity, free electron transport, and thermal diffusion in defect-free silica for temperatures up to 15,000K and pressures < 15GPa. In addition to the practical application of selecting an optimal laser for pre-initiation of large aperture optics, this work serves as a platform for understanding general laser-matter interactions in dielectrics under a variety of conditions.

Carr, C W; Bude, J D; Shen, N; Demange, P

2010-10-26

170

Evolution  

NSDL National Science Digital Library

As a companion to the seven-part, eight-hour television series, PBS's Website offers an in-depth look at the history and complexities of evolution. From Darwin's Origin of Species to the role of religion, this site explores the topic in vivid detail. All interested will discover excellent information, but K-12 teachers will find the Teachers & Students section especially valuable. Here, resources on methods of teaching and understanding evolution are provided in online courses and guides. The site features a number of multimedia elements, film clips and interactive displays, and surfers with older computers and slow modems will want to choose the low bandwidth options when they are available.

171

Low-Velocity Impact and Damage Process of Composite Laminates  

Microsoft Academic Search

Several important issues regarding damage simulation of composite laminates due to low velocity impact were investigated including contact law, damage initiation and the corresponding change of stiffness, and damping. Continuum damage mechanics was applied to account for the change of mechanical properties of damaged materials. The Hertzian contact law was modified in order to accommodate the serious damage in the

Zhidong Guan; Chihdar Yang Yang

2002-01-01

172

Mechanical Response of Stitched T300 Mat/Urethane 420 IMR Composite Laminates: Property/Orientation Dependence and Damage Evolution  

SciTech Connect

This report presents experimental and analytical results of investigations on the mechanical response of stitched T300 mat/urethane 420 IMR composite laminates with three different lay-up configurations. Tensile tests and short-term creep and recovery tests were conducted on the laminate coupons at various orientations. The X-ray photographic technique was adopted to detect the internal damage due to external loading history. The tensile data of laminates with antisymmetric and symmetric lay-ups indicated that lay- up sequences of cross-ply laminates do not have much influence on their tensile properties. However, misalignments within the stitch-bonded plies disturb the symmetry of intended quasi-isotropic laminates and thereby cause the mechanical properties to exhibit a certain amount of angular dependence. Classic lamination theory was found to be able to provide a very good prediction of tensile properties for the stitched laminates within linear range. Creep and recovery response of laminate coupons is greatly dependent on loading angles and load levels. The internal damage of laminate coupons is also directly related to loading angles and load levels as well as loading history.

Deng, S.; Weitsman, Y.J.

2000-03-01

173

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

174

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

175

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

176

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

177

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

178

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

179

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

180

An anisotropic gradient damage model for quasi-brittle materials  

Microsoft Academic Search

An anisotropic continuum damage model based on the microplane concept is elaborated. Scalar damage laws are formulated on several individual microplanes representing the planes of potential failure. These uniaxial constitutive laws can be cast into a fourth-order damage formulation such that anisotropy of the overall constitutive law is introduced in a natural fashion. Strain gradients are incorporated in the constitutive

Ellen Kuhl; Ekkehard Ramm; René de Borst

2000-01-01

181

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

182

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

E-print Network

LAW, HISTORY, &LAW, HISTORY, &LAW, HISTORY, & CULTURECULTURECULTURE The Law, History, and Culture specific legal issues through a humanistic lens. Opportunities for Students Phi Alpha Theta: This history honor society seeks to bring students, teachers, and writers of history together for intellectual

Rohs, Remo

183

Tensile fatigue damage and degradation of random short-fiber SMC composite  

SciTech Connect

Fatigue damage and degradation in a random short-fiber SMC-R50 composite were investigated experimentally and theoretically. In the study of homogeneous damage, experiments were conducted to examined fundamental mechanisms and characteristics of fatigue damage and its evolution. The statistical nature of microcracks was evaluated by the introduction of damage distribution functions. Results showed that the cumulative distribution and density of microcrack length followed the form of a three-parameter Weibull function, whereas those of orientation followed a power form of the cos(theta) function. Constitutive equations for the damaged composite are derived based on the self-consistent mechanics scheme in conjunction with a three-dimensional elastic crack theory and probabilistic functions. Agreement between theoretical predictions and experimental data is excellent. The theory and analysis are able to evaluate the tensorial nature of fatigue damage and degradation of all material elastic constants. A damage tensor is introduced to describe quantitatively the degree of homogeneous fatigue damage. Stiffness degradation is related to the rate of change of microcrack evolution and accumulation, and a power-law relationship is found between the rate of damage development and fatigue loading cycles.

Chim, E.S.M.

1985-01-01

184

Optimal dynamic law enforcement  

Microsoft Academic Search

In this paper we present an intertemporal extension of Becker's [Journal of Political Economy 76 (1968) 169] static economic approach to crime and punishment. For a dynamic supply of offenders we determine the optimal dynamic trade-off between damages caused by offenders, law enforcement expenditures and cost of imprisonment. By using Pontryagin's maximum principle we obtain interesting insight into the dynamical

Gustav Feichtinger; Waltraud Grienauer; Gernot Tragler

2002-01-01

185

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

186

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

187

Gender Law  

Microsoft Academic Search

The inauguration of the DUKE JOURNAL OF GENDER LAW & POLICY represents an exciting step in the institutionalization of a subject area in academic law formerly found only at the fringe of legal scholarship and law school curriculums. Often shunned as a political activity inappropriate to institutions committed to academic rigor, objectivity, and neutrality, gender law has begun to lay

Katharine T. Bartlett

1994-01-01

188

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

189

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

190

Law and economics in Spain  

Microsoft Academic Search

This chapter addresses the evolution and current situation of law and economics in Spain along four major dimensions: teaching, academic research, legal policy and judicial practice. A glance at trends and likely extensions is also included. Furthermore, an accompanying Spanish bibliography in law and economics provides detailed information on a wide variety of research fields and authors, following the guidelines

Santos Pastor; Jesús Pintos

1991-01-01

191

Gas Laws  

NSDL National Science Digital Library

In this activity, students study gas laws at a molecular level. They vary the volume of a container at constant temperature to see how pressure changes (Boyle's Law), change the temperature of a container at constant pressure to see how the volume changes with temperature (Charles’s Law), and experiment with heating a gas in a closed container to discover how pressure changes with temperature (Gay Lussac's Law). They also discover the relationship between the number of gas molecules and gas volume (Avogadro's Law). Finally, students use their knowledge of gas laws to model a heated soda can collapsing as it is plunged into ice water.

The Concord Consortium

2011-12-11

192

A damage model for masonry structures  

Microsoft Academic Search

In this paper a brittle damage model for masonry structures characterized by a unit cell composed of mortar, blocks and a finite number of fractures is proposed. Initially, a micromechanically consistent binary representation of the damage variable is proposed for regular heterogeneous media, and a discrete damage kinetic law is developed. Then, a typical masonry material is considered and a

R. Luciano; E. Sacco

1998-01-01

193

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

194

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

195

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 180sp°C, 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

196

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.

Department of Physics and Astronomy

197

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

198

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.

199

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

200

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

201

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,

202

Exact law of live nature  

NASA Astrophysics Data System (ADS)

Exact law of mortality dynamics in changing populations and environment is derived. It includes no explicit characteristics of animal- environment interactions (metabolism etc) which are a must for life; it is universal for all animals, from single cell yeast to humans, with their drastically different biology, evolutionary history, and complexity; it is rapidly (within few percent of life span) reversible. Such law is unique for live systems with their homeostatic self-adjustment to environment (cf. thermodynamics of liquids and glasses). The law which is valid for all live, and only live, systems is their specific natural law. Mortality is an instrument of natural selection and biological diversity. Its law, which is preserved in evolution of all species, is a conservation law of mortality, selection, evolution, biology. The law implies new kind of intrinsic mortality and adaptation which dominate in evolutionary unprecedented protected populations and, in contrast to species specific natural selection, proceed via universal stepwise rungs and reduce to universal cellular mechanism. The law demonstrates that intrinsic mortality and at least certain aspects of aging are disposable evolutionary byproducts, and directed genetic and/or biological changes may yield healthy and vital Methuselah lifespan. This is consistent with experiments. Universality implies that single cell yeast may provide a master key to the cellular mechanism of universal mortality, aging, selection, evolution, and its regulation in all animals. One may look for its manifestations in animal cells also, e.g., in their replicative senescence and cancer. Evolutionary origin and genetic nature of universality are suggested.

Azbel, Mark Ya.

2005-07-01

203

Cumulative fatigue damage models  

NASA Technical Reports Server (NTRS)

The problem of calculating expected component life under fatigue loading conditions is complicated by the fact that component loading histories contain, in many cases, cyclic loads of widely varying amplitudes. In such a case a cumulative damage model is required, in addition to a fatigue damage criterion, or life relationship, in order to compute the expected fatigue life. The traditional cumulative damage model used in design is the linear damage rule. This model, while being simple to use, can yield grossly unconservative results under certain loading conditions. Research at the NASA Lewis Research Center has led to the development of a nonlinear cumulative damage model, named the double damage curve approach (DDCA), that has greatly improved predictive capability. This model, which considers the life (or loading) level dependence of damage evolution, was applied successfully to two polycrystalline materials, 316 stainless steel and Haynes 188. The cumulative fatigue behavior of the PWA 1480 single-crystal material is currently being measured to determine the applicability of the DDCA for this material.

Mcgaw, Michael A.

1988-01-01

204

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

205

MULTI-WAVELENGTH OBSERVATIONS OF THE SPATIO-TEMPORAL EVOLUTION OF SOLAR FLARES WITH AIA/SDO. II. HYDRODYNAMIC SCALING LAWS AND THERMAL ENERGIES  

SciTech Connect

In this study we measure physical parameters of the same set of 155 M- and X-class solar flares observed with AIA/SDO as analyzed in Paper I, by performing a differential emission measure analysis to determine the flare peak emission measure EM{sub p} , peak temperature T{sub p} , electron density n{sub p} , and thermal energy E{sub th}, in addition to the spatial scales L, areas A, and volumes V measured in Paper I. The parameter ranges for M- and X-class flares are log (EM{sub p}) = 47.0-50.5, T{sub p} = 5.0-17.8 MK, n{sub p} = 4 × 10{sup 9}-9 × 10{sup 11} cm{sup –3}, and thermal energies of E{sub th} = 1.6 × 10{sup 28}-1.1 × 10{sup 32} erg. We find that these parameters obey the Rosner-Tucker-Vaiana (RTV) scaling law T{sub p}{sup 2}?n{sub p} L and H?T {sup 7/2} L {sup –2} during the peak time t{sub p} of the flare density n{sub p} , when energy balance between the heating rate H and the conductive and radiative loss rates is achieved for a short instant and thus enables the applicability of the RTV scaling law. The application of the RTV scaling law predicts power-law distributions for all physical parameters, which we demonstrate with numerical Monte Carlo simulations as well as with analytical calculations. A consequence of the RTV law is also that we can retrieve the size distribution of heating rates, for which we find N(H)?H {sup –1.8}, which is consistent with the magnetic flux distribution N(?)??{sup –1.85} observed by Parnell et al. and the heating flux scaling law F{sub H} ?HL?B/L of Schrijver et al.. The fractal-diffusive self-organized criticality model in conjunction with the RTV scaling law reproduces the observed power-law distributions and their slopes for all geometrical and physical parameters and can be used to predict the size distributions for other flare data sets, instruments, and detection algorithms.

Aschwanden, Markus J. [Lockheed Martin Advanced Technology Center, Org. ADBS, Bldg. 252, 3251 Hanover St., Palo Alto, CA 94304 (United States); Shimizu, Toshifumi, E-mail: aschwanden@lmsal.com, E-mail: shimizu.toshifumi@isas.jaxa.jp [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan)

2013-10-20

206

Humans are still evolving, scientists find Darwinian survival-of-the-fittest laws continue to shape human evolution in the modern age, research has shown.  

E-print Network

Humans are still evolving, scientists find Darwinian survival-of-the-fittest laws continue to shape: survival to adulthood, mate access, mating success, and fertility. They found that the Finns' natural-a-liar-the-hint-of-a-smile-and-raised- eyebrows.html) Differences in early survival and fertility were responsible for most of the variation

Lummaa, Virpi

207

Cumulative damage theory in multiaxial fatigue of graphite/epoxy (+/-45)s composites and weight function theory for a rectilinear anisotropic body  

SciTech Connect

The phenomenological evolution laws of damage based on residual life and residual strength were critically examined. The failure of a specimen can be defined immediately before or after fracture. The former is called failure defined by approach II and the latter failure defined by approach I. Usually at failure there is discontinuity of forcing variables and, because of this, damage at failure is discontinuous. Therefore, the values of damage at failure by two different approaches are not the same. Based on this idea the sequence effects of the phenomenological evolution law of damage were studied. A multiaxial growth law of damage was proposed based on experimental data of axial, torsional, combined axial and torsional inphase, and step-loading fatigue in thin-walled graphite epoxy tubes consisting of four layers of (+-45)/sub s/ laminates. Interlaminar normal stress effect on the fatigue behavior of a tubular specimen was studied experimentally. In the second part of this thesis, Bueckner's weight function theory is extended to rectilinear anisotropic bodies for two-dimensional loading systems

An, D.M.

1986-01-01

208

Heavy-ion irradiations of Fe and Fe-Cr model alloys part 2: damage evolution in thin-foils at higher doses.  

SciTech Connect

A study of heavy-ion damage in Fe and Fe-Cr alloys started in Part 1 1 was continued with an investigation of damage development in UHP Fe and Fe-8%Cr at higher doses up to 2 x 10{sup 19} ions m{sup -2} ({approx}13 dpa). In thin-foil irradiations with 150 keV Fe{sup +} ions at 300 C and room temperature (RT), more complex microstructures started to develop in thicker regions of the foils at doses greater than about 2 x 10{sup 18} ions m{sup -2}, apparently involving cooperative interaction, alignment and coalescence of smaller loops. First strings of loops all with the same 1/2 111 Burgers vectors formed. In UHP Fe irradiated at 300 C the damage then developed into colonies of resolvable interstitial loops with 1/2 111 Burgers vectors. By a dose of 2 x 10{sup 19} ions m{sup -2}, large (several hundred nanometer) finger-shaped loops with large shear components had developed by the growth and subsequent coalescence of smaller loops. Similar but finer-scale damage structures developed in UHP Fe irradiated at RT and in Fe-8%Cr irradiated at both RT and 300 C.

Hernandez-Mayoral, M.; Yao, Z.; Jenkins, M. L.; Kirk, M. A.; CIEMAT Avenida Complutense; Univ. Oxford

2008-07-21

209

Law's Republics  

Microsoft Academic Search

This paper was delivered as a Provocation at a Symposium in Honor of Professor Frank Michelman, hosted at Harvard Law School in February 2012. Using Professor Michelman’s extraordinary body of work in comparative constitutional law, the essay explores the importance of the oft-neglected normative dimension of comparative analysis. Far from endorsing a binary choice between legal function and legal culture,

Vlad Perju

2012-01-01

210

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 â??Articlesâ? 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-

211

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

212

Flexure with Damage  

NASA Astrophysics Data System (ADS)

Investigations in structural geology and geophysics often apply continuum mechanics to solve problems relating to the deformation of the crust and lithosphere, such as the bending of strata due to a laccolith, bending of the lithosphere under island chains, bending of the lithosphere at an ocean trench. These solutions are largely based on linear elasticity. However, many processes involve stresses that exceed the elastic limit. Thus plastic, as well as elastic, deformation occurs. The temporal and spatial changes in material rheology and the nonlinear nature of the process preclude the development of analytical solutions in these complex cases. To account for the evolving rheology, we apply continuum damage mechanics as an empirical method to solve the problem of a bending beam. We use a numerical method to obtain quasi-static solutions to the Navier equation. We use the program GeoFEST v 4.5 (Geophysical Finite Element Simulation Tool), developed by NASA Jet Propulsion Laboratory, to generate solutions for each time step. Where the Von Mises stresses exceed the critical stress, we apply damage to the elements and reduce the shear modulus of the element. Damage is calculated for each time step by a power law relationship of the ratio of the critical stress to the Von Mises stress and the critical strain to the Von Mises strain, accounting for relaxation of the material due to increasing damage. To test our method, we apply damage rheology to a 2-D simple beam deforming under its own weight. This problem can be considered an analog for folding. Where stresses exceed the critical stress, we simulate the formation of damage and observe the time-dependent relaxation of the stress and strain to levels below the plastic limit. Thus damage can be used as a proxy for irreversible deformation in the fold hinge area, representing brittle fracture and microcracking where extensional fiber stresses dominate, and material dissolution where compressional fiber stresses dominate.

Manaker, D. M.; Turcotte, D. L.; Kellogg, L. H.; Lyzenga, G. A.

2004-12-01

213

Law enforcement agencies have exploited biometrics for decades as key tools in forensic identification. With the evolution in information technology and the huge volume of  

E-print Network

identification. With the evolution in information technology and the huge volume of cases that need as withstand severe conditions usually encountered in mass disasters. Dental features are the best candidates in its strategic plan the creation of an Automated Dental Identification System (ADIS), with similar

Abaza, Ayman

214

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

215

Full-Scale Prestress Loss Monitoring of Damaged RC Structures Using Distributed Optical Fiber Sensing Technology  

PubMed Central

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

216

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

217

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

218

Chinese Business Law Postgraduate  

E-print Network

) · 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 · Financial law · Foreign exchange regulation · Government procurement law · Price fixing regulations Courses

Einmahl, Uwe

219

Flexure with damage  

NASA Astrophysics Data System (ADS)

Ductile behaviour in rocks is often associated with plasticity due to dislocation motion or diffusion under high pressures and temperatures. However, ductile behaviour can also occur in brittle materials. An example would be cataclastic flow associated with folding at shallow crustal levels. Engineers utilize damage mechanics to model the continuum deformation of brittle materials. In this paper we utilize a modified form of damage mechanics that includes a yield stress. Here, damage represents a reduction in frictional strength. We use this empirical approach to simulate bending of the lithosphere through the problem of plate flexure. We use numerical simulations to obtain quasi-static solutions to the Navier equations of elasticity. We use the program GeoFEST v. 4.5 (Geophysical Finite Element Simulation Tool), developed by NASA Jet Propulsion Laboratory, to generate solutions for each time step. When the von Mises stress exceeds the critical stress on an element we apply damage to reduce the shear modulus of the element. Damage is calculated at each time step by a power-law relationship of the ratio of the critical stress to the von Mises stress and the critical strain to the von Mises strain. This results in the relaxation of the material due to increasing damage. To test our method, we apply our damage rheology to a semi-infinite plate deforming under its own weight. Where the von Mises stress exceeds the critical stress, we simulate the formation of damage and observe the time-dependent relaxation of the stress and strain to near the yield strength. We simulate a wide range of behaviours from slow relaxation to instantaneous failure, over timescales that span six orders of magnitude. Using this method, stress relaxation produces perfectly plastic behaviour in cases where failure does not occur. For cases of failure, we observe a rapid increase in damage, analogous to the acceleration of microcrack formation and acoustic emissions prior to failure. Thus continuum damage mechanics can be used to simulate the irreversible deformation of brittle materials.

Manaker, David M.; Turcotte, Donald L.; Kellogg, Louise H.

2006-09-01

220

Lawful Inspections.  

ERIC Educational Resources Information Center

The sanitarian often spends much of his working day performing, reviewing, or supervising inspections. It is important that the sanitarian realize the legal implications of inspections and be prepared to perform them in accordance with the law. (RE)

Sikora, Vincent A.

1979-01-01

221

Ohm's Law  

NSDL National Science Digital Library

In this interactive simulation of Ohm’s law, adapted from the University of Colorado's Physics Education Technology project, adjust the voltage and resistance in a circuit, and observe how this affects the flow of current.

2007-04-19

222

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

223

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.

Lynn Cominsky

2010-01-01

224

Multi-Wavelength Observations of the Spatio-Temporal Evolution of Solar Flares with AIA/SDO: II. Hydrodynamic Scaling Laws and Thermal Energies  

E-print Network

In this study we measure physical parameters of the same set of 155 M and X-class solar flares observed with AIA/SDO as analyzed in Paper I, by performing a {\\sl differential emission measure (DEM)} analysis to determine the flare peak emission measure $EM_p$, peak temperature $T_p$, electron density $n_p$, and thermal energy $E_{th}$, in addition to the spatial scales $L$, areas $A$, and volumes $V$ measured in Paper I. The parameter ranges for M and X-class flares are: $\\log(EM_p)=47.0-50.5$, $T_p=5.0-17.8$ MK, $n_p=4 \\times 10^9-9 \\times 10^{11}$ cm$^{-3}$, and thermal energies of $E_{th}=1.6 \\times 10^{28}-1.1 \\times 10^{32}$ erg. We find that these parameters obey the Rosner-Tucker-Vaiana (RTV) scaling law $T_p^2 \\propto n_p L$ and $H \\propto T^{7/2} L^{-2}$ during the peak time $t_p$ of the flare density $n_p$, when energy balance between the heating rate $H$ and the conductive and radiative loss rates is achieved for a short instant, and thus enables the applicability of the RTV scaling law. The applic...

Aschwanden, Markus J

2013-01-01

225

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

226

Right Hemisphere Brain Damage  

MedlinePLUS

Right Hemisphere Brain Damage [ en Español ] What is right hemisphere brain damage ? What are some signs or symptoms of right hemisphere ... right hemisphere brain damage ? What is right hemisphere brain damage? Right hemisphere brain damage (RHD) is damage ...

227

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

NASA Astrophysics Data System (ADS)

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

2012-02-01

228

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

229

Sun Damage  

MedlinePLUS

... Keratosis (Solar Keratosis) Actinic keratoses, also known as solar keratoses, are small rough or scaly areas of skin due to damage from sun exposure. Some actinic keratoses can turn into squamous cell skin cancer, so it is important to perform… ...

230

A GRADIENT ENHANCEMENT WITH APPLICATION TO ANISOTROPIC CONTINUUM DAMAGE  

Microsoft Academic Search

The paper focuses on the modelling of the quasi-brittle failure of materials with a heterogeneous microstructure. Failure induced anisotropy is incorporated in terms of the microplane theory. This theory is based on scalar damage laws formulated on several individual material planes. Anisotropy of the overall constitutive law is introduced in a natural fashion by transforming the scalar valued damage operators

Ellen Kuhl; Ekkehard Ramm; Koiter Insitute Delft

1998-01-01

231

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 of Glasgow is one of the leading and most successful Law Schools in the UK. Nationally renowned to be among the top 7 Law Schools in the UK, second to none in Scotland and among the top 40 Law Schools

Guo, Zaoyang

232

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 Å) to test the wavelength dependence of scaling laws and statistical distributions. Except for the 171 and 193 Å 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 0.94±0.01} 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

233

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

234

Exact law of live nature  

NASA Astrophysics Data System (ADS)

The exact law of mortality dynamics in changing populations and environment is derived. It includes no explicit characteristics of animal-environment interactions (metabolism, etc.) which are a must for life; it is universal for all animals, from single-cell yeast to humans, with their drastically different biology, evolutionary history, and complexity; it is rapidly (within few percent of life span) reversible. Such a law is unique for live systems with their homeostatic self-adjustment to environment (cf. thermodynamics of liquids and glasses). The law which is valid for all live, and only live, systems is their specific natural law. Mortality is an instrument of natural selection and biological diversity. Its law, which is preserved in evolution of all species, is a conservation law of mortality, selection, evolution, biology. The law implies new kinds of intrinsic mortality and adaptation which dominate in evolutionary unprecedented protected populations and, in contrast to species-specific natural selection, proceed via universal stepwise rungs and reduce to universal cellular mechanism. The law demonstrates that intrinsic mortality and at least certain aspects of aging are disposable evolutionary byproducts, and directed genetic and/or biological changes may yield healthy and vital Methuselah lifespan. This is consistent with experiments. Universality implies that single-cell yeast may provide a master key to the cellular mechanism of universal mortality, aging, selection, evolution, and its regulation in all animals. One may look for its manifestations in animal cells also, e.g., in their replicative senescence and cancer. Evolutionary origin and genetic nature of universality are suggested.

Azbel?, Mark Ya.

2005-08-01

235

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.

236

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. M.

237

Faraday's Law  

NSDL National Science Digital Library

Light a light bulb by waving a magnet. This simulation of a Faraday's Law is from the Physics Education Technology website of University of Colorado. It is accessible for teachers and students alike. Included are links to related topics and additional ideas and activities for teachers to use.

238

Bragg's Law  

NSDL National Science Digital Library

It may be beneficial to have students perform the Wave Interference activity prior to engaging them in this activity. The following handouts are identical, with the exception that one is in Word format, while the other is in PDF format. The students should perform the exercise in a computer laboratory. Before proceeding through the questions, they should be given an opportunity to review the material on this web page. Bragg\\'s Law Activity Sheet (Acrobat (PDF) 73kB Mar2 10) Bragg\\'s Law Activity Sheet for Word (Microsoft Word 37kB Feb25 10) The following Powerpoint presentation can be used as an introduction to Bragg's Law. Bragg\\'s Law Powerpoint Presentation (PowerPoint 974kB Feb25 10) Wave Interference Activity Prior to investigating Bragg's law through this activity, it may be helpful to explore interference of sinusoidal waveforms by following the link below. Wave Interference Activity Bragg's Law Applet Java Applet created by Konstantin Lukin with supervision by Glenn A. Richard, Project Java Webmaster Original Bragg's Law Applet page on Mineral Physics Institute web server at Stony Brook University: Project Java - Bragg's Law and Diffraction: How waves reveal the atomic structure of crystals Bragg's Law refers to the simple equation: nÎ = 2d sinÎ derived by the English physicists Sir W.H. Bragg and his son Sir W.L. Bragg in 1913 to explain why the cleavage faces of crystals appear to reflect X-ray beams at certain angles of incidence (Î, Î). The variable d is the distance between atomic layers in a crystal, and the variable lambda is the wavelength of the incident X-ray beam (see applet); n is an integer. This observation is an example of X-ray wave interference (Roentgenstrahlinterferenzen), commonly known as X-ray diffraction (XRD), and was direct evidence for the periodic atomic structure of crystals postulated for several centuries. The Braggs were awarded the Nobel Prize in physics in 1915 for their work in determining crystal structures beginning with NaCl, ZnS and diamond. Although Bragg's law was used to explain the interference pattern of X-rays scattered by crystals, diffraction has been developed to study the structure of all states of matter with any beam, e.g., ions, electrons, neutrons, and protons, with a wavelength similar to the distance between the atomic or molecular structures of interest. How to Use this Applet The applet shows two rays incident on two atomic layers of a crystal, e.g., atoms, ions, and molecules, separated by the distance d. The layers look like rows because the layers are projected onto two dimensions and your view is parallel to the layers. The applet begins with the scattered rays in phase and interferring constructively. Bragg's Law is satisfied and diffraction is occurring. The meter indicates how well the phases of the two rays match. The small light on the meter is green when Bragg's equation is satisfied and red when it is not satisfied. The meter can be observed while the three variables in Bragg's are changed by clicking on the scroll-bar arrows and by typing the values in the boxes. The d and Î variables can be changed by dragging on the arrows provided on the crystal layers and scattered beam, respectively. Bragg's Law Applet with details meter activated, but no constructive interference. Note that the peaks and troughs on the scattered beams are not aligned. Bragg's Law Applet with constructive interference and n = 2. Note that the peaks and troughs on the scattered beams are aligned. Deriving Bragg's Law by Paul Schields Bragg's Law can easily be derived by considering the conditions necessary to make the phases of the beams coincide when the incident angle equals and reflecting angle. The rays of the incident beam are always in phase and parallel up to the point at which the top beam strikes the top layer at atom z (Fig. 1). The second beam continues to the next layer where it is scattered by atom B. The second beam must travel the extra distance AB + BC if the two beams are to continue traveling adjacent and parallel. This extra distance must be an integra

Glenn Richard

239

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

240

Faraday's Law and Ampere's Law  

Microsoft Academic Search

It is suggested that the origin of the induced electromotive force in a stationary circuit, given by Faraday's law of induction, could be made clearer to a beginning student if emphasis were placed in introductory courses on the geometry of the induced electric field set up by a time-varying magnetic field instead of on the line integral of this field

Francis W. Sears

1963-01-01

241

A continuum damage model of fatigue-induced damage in laminated composites  

NASA Technical Reports Server (NTRS)

A model is presented which predicts the stress-strain behavior of continuous fiber reinforced laminated composites in the presence of microstructural damage. The model is based on the concept of continuum damage mechanics and uses internal state variables to characterize the various damage modes. The associated internal state variable growth laws are mathematical models of the loading history induced development of microstructural damage. The model is demonstrated by using it to predict the response of damaged AS-4/3502 graphite/epoxy laminate panels.

Harris, Charles E.; Allen, David H.

1988-01-01

242

Faculty of Law Faculty of Law  

E-print Network

Faculty of Law Faculty of Law (141) Credit Hours Academic Year:2012/2013 Second: Faculty Compulsory " Inheritance & Wills" 0410373 Pre-req Course Cr.Course NameCourse No. ---------3Introduction To Law0410111 04101113Sources of Obligation0410112 ----------3Principles of Commercial Law0410131 ----------3Criminal Law

243

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

244

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

245

Life Driven by Damaged Damage  

NASA Astrophysics Data System (ADS)

Although life is destined to be approximately described as aself-referential form, the self-reference is invalidated and life avoids a contradiction. Since life does not include any contradiction, it reveals a unity as a whole. Since life is not a self-circulation, it implements diversity and evolvability. Here we show life as invalidated self-reference by constructing a model cell driven by damaged damage. Since life is always close to destruction, it exhibits both of the amoebic motion and the intelligent Physarum-like behavior.

Gunji, Y.-P.; Shirakawa, T.; Niizato, T.; Haruna, T.; Balaz, I.

246

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

247

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

248

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.

2014-09-18

249

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 Green’s 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

250

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

251

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; Pál, Gerg?; Lennartz-Sassinek, Sabine; Butler, Ian; Main, Ian

2013-04-01

252

White settlers and the law in early colonial Kenya  

Microsoft Academic Search

This article examines settler attitudes toward the law and the legal system in early colonial Kenya. Settlers believed that English law was the culmination of centuries of evolution and was unsurpassed for its justice and logic. Nonetheless, they insisted English law and legal procedure were supremely ill-suited for the African context. When courts released Africans on “technicalities” it only encouraged

Brett Shadle

2010-01-01

253

TOPOGRAPHIES LAW / DROIT  

E-print Network

THE LAYERS OF LAW TOPOGRAPHIES DU DROIT Faculty of Law Faculté de droit LAW / DROIT AUTOMNE FALL/ 2011 #12;2 FOCUS | LAW ­ FALL / AUTOMNE 2011 ­ MCGILL UNIVERSITY FALL/AUTOMNE 2011 RédactRices en chef Sebastiao, Development Coordinator, alumnioffice.law@mcgill.ca Telephone: 514.398.3679 Focus Law est publié

Fabry, Frederic

254

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

255

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

256

43 CFR 11.17 - Compliance with applicable laws and standards.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 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...

2010-10-01

257

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

258

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

259

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

260

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

261

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

262

The Law School Studies in Law & Criminology  

E-print Network

The Law School Studies in Law & Criminology #12;We know that making the right choices about your studies is an essential step towards fulfilling your aspirations. As the top law school in the North from the School have some of the best employment prospects in the country, and regularly give the Law

Diggle, Peter J.

263

School of Law Canterbury Law Scholarships  

E-print Network

can be made on this form or by downloading a form from the School of Law website at wwwSchool of Law 13 Canterbury Law Scholarships School of Law #12;Application Form 1. Name: ....................................................................................................................................................................... 3. Secondary School School attended in Year 13

Hickman, Mark

264

Entropic Corrections to Coulomb's Law  

NASA Astrophysics Data System (ADS)

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 ?. Our study further supports the unification of gravity and electromagnetic interactions based on the holographic principle.

Hendi, S. H.; Sheykhi, A.

2012-04-01

265

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.

266

[Endophthalmitis and French law].  

PubMed

Endophthalmitis is the nosocomial infection occurring in ophthalmology. In 1988, the French Ministry of Health defined nosocomial infection as an illness caused by microorganisms and contracted in a care establishment. In the same year, decrees and stipulations relating to sanitary safety prescribed new duties for care establishments. Patients who have suffered nosocomial infection can claim compensation either through an administrative tribunal if they were treated in a hospital, or through an ordinary court if they were treated privately. Administrative jurisprudence does not allow for the exoneration of the hospital's responsibility, except where there is proof of an external cause. In ordinary law, where jurisprudence was for many years based on the duty of best efforts, victims were not indemnified. In 1996, the Court of Cassation decided that a clinic is presumed responsible for a nosocomial infection unless it can prove that there was no error on its part. Since 1999, private health establishments have a duty to secure results. The act of 4 March, 2002, states that care establishments, whether public or private, are responsible for damages resulting from nosocomial infections, except where they can prove the existence of an external cause. Where the infection results in permanent partial disability of more than 24%, and is not due to malpractice in the care establishment, the responsibility for damages is taken over by National Solidarity. PMID:15077473

Monestier-Carlus, D

2004-01-01

267

SIMULATION OF PROGRESSIVE DAMAGE IN BOLTED COMPOSITE JOINTS  

Microsoft Academic Search

Recently, a continuum based progressive damage model for fiber-reinforced composites became available in the commercial finite element code ABAQUS. The implemented model uses the Hashin damage initiation criteria (1,2) and damage evolution is based on the work of Matzenmiller (3) and Camanho and Davila (4). The \\

Hannes Koerber; Pedro P. Camanho

268

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 damage mechanics (CDM) is a powerful tool to model the degrada- tion of materials, the stress softening

269

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

270

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

271

77 FR 19799 - Pipeline Safety: Pipeline Damage Prevention Programs  

Federal Register 2010, 2011, 2012, 2013, 2014

...Group (EPPG) [cir] LDH Energy Pipeline, L.P. [cir] Marathon Pipeline [cir] Michigan Consolidated Gas Company [cir...responsibility for administering the damage prevention laws?'' Marathon Pipeline commented that a state agency should be...

2012-04-02

272

Continuum damage modeling of ice shelves: inversion of surface velocities for a state damage variable  

NASA Astrophysics Data System (ADS)

Continuum damage mechanics is a promising alternative to fracture mechanics for representing rifting, crevassing and calving processes in ice sheet models. The constitutive relations describing ice rheology can be modified using state variables which describe the effects of cracking and damage without explicitly seeking to resolve individual cracks. The challenge in formulating a damage model for application in a large-scale ice sheet model is in the computational cost associated with the increase in model complexity and the addition of a differential equation describing the evolution of damage. We present an investigation of the spatial distribution of damage for the Larsen C ice shelf using a scalar isotropic damage model implemented in the Ice Sheet System Model (ISSM). The representation of damage using a single scalar is a simple but numerically efficient approach to accounting for the effects of fractures on ice flow. InSAR-derived surface velocities are used to invert for the scalar damage variable, leading to a spatial map of damage analogous to that produced by inverting for the ice rigidity itself. The key distinction in inverting for the damage variable is that thermal and mechanical components of the constitutive relation are formally separated in the inversion. This spatial mapping of damage is a key first step in forward modeling of the stability of ice shelves using damage mechanics, and we discuss ongoing work to implement a transient damage model in ISSM to project the mechanical integrity of ice shelves in a warming climate.

Borstad, C.; Larour, E.; Morlighem, M.; Seroussi, H.; Rignot, E.

2012-04-01

273

The Ultimate Law of Social Evolution  

E-print Network

mind. They are s t i l l n a t u r a l products of i n d i v i d u a l hah i t hut they are f i n a l l y modi­ f i e d by the s o c i a l - s e l f , which chooses and sanct ions . Development of a s s o c i a t i o n into intimacy and, above a l l... are changed into a r t i c l e s of beauty and magnificence. T h i r d , we have that of adaptation in i t s narrow­ er sense whereby man e x e r c i s e the knowledge o f h i s existence bv wav o f shaping and a d j u s t i n g h i s circumstances...

Overlander, Jacob Alphaeus

1901-05-23

274

Demonstrating the Gas Laws.  

ERIC Educational Resources Information Center

Presents a complete computer program demonstrating the relationship between volume/pressure for Boyle's Law, volume/temperature for Charles' Law, and volume/moles of gas for Avagadro's Law. The programing reinforces students' application of gas laws and equates a simulated moving piston to theoretical values derived using the ideal gas law

Holko, David A.

1982-01-01

275

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

276

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 and divorce laws, as well as sample Utah divorce forms. Some of these forms are patterned after forms I used

Seamons, Kent E.

277

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 AND DIVORCE LAWS Steve Averett 2012 Edition #12;ii For Suz and family #12;iii Introduction This manual

Seamons, Kent E.

278

Prolegomenon to patterns in evolution.  

PubMed

Despite Darwin, we remain children of Newton and dream of a grand theory that is epistemologically complete and would allow prediction of the evolution of the biosphere. The main purpose of this article is to show that this dream is false, and bears on studying patterns of evolution. To do so, I must justify the use of the word "function" in biology, when physics has only happenings. The concept of "function" lifts biology irreducibly above physics, for as we shall see, we cannot prestate the ever new biological functions that arise and constitute the very phase space of evolution. Hence, we cannot mathematize the detailed becoming of the biosphere, nor write differential equations for functional variables we do not know ahead of time, nor integrate those equations, so no laws "entail" evolution. The dream of a grand theory fails. In place of entailing laws, I propose a post-entailing law explanatory framework in which Actuals arise in evolution that constitute new boundary conditions that are enabling constraints that create new, typically unprestatable, adjacent possible opportunities for further evolution, in which new Actuals arise, in a persistent becoming. Evolution flows into a typically unprestatable succession of adjacent possibles. Given the concept of function, the concept of functional closure of an organism making a living in its world becomes central. Implications for patterns in evolution include historical reconstruction, and statistical laws such as the distribution of extinction events, or species per genus, and the use of formal cause, not efficient cause, laws. PMID:24704211

Kauffman, Stuart A

2014-09-01

279

Damaged Skylab  

NASA Technical Reports Server (NTRS)

The Saturn V vehicle, carrying the unmarned orbital workshop for the Skylab-1 mission, lifted off successfully and all systems performed normally. Sixty-three seconds into the flight, engineers in the operation support and control center saw an unexpected telemetry indication that signalled that damages occurred on one solar array and the micrometeoroid shield during the launch. The micrometeoroid shield, a thin protective cylinder surrounding the workshop, that protected it from tiny space particles and the sun's scorching heat, ripped loose from its position around the workshop. This caused the loss of one solar wing and jammed the other. Still unoccupied, the Skylab was stricken with the loss of the heat shield and sunlight beat mercilessly on the lab's sensitive skin. Internal temperatures soared, rendering the station uninhabitable, threatening foods, medicines, films, and experiments. This image, taken during a fly-around inspection by the Skylab-2 crew, shows the exterior skin of the workshop discolored by solar radiation. The Marshall Space Flight Center (MSFC) developed, tested, rehearsed, and approved three repair options. These options included a parasol sunshade and a twin-pole sunshade to restore the temperature inside the workshop, and a set of metal cutting tools to free the jammed solar panel.

1973-01-01

280

Damaged Skylab  

NASA Technical Reports Server (NTRS)

The Saturn V vehicle, carrying the unmarned orbital workshop for the Skylab-1 mission, lifted off successfully and all systems performed normally. Sixty-three seconds into the flight, engineers in the operation support and control center saw an unexpected telemetry indication that signalled that damages occurred on one solar array and the micrometeoroid shield during the launch. The micrometeoroid shield, a thin protective cylinder surrounding the workshop protecting it from tiny space particles and the sun's scorching heat, ripped loose from its position around the workshop. This caused the loss of one solar wing and jammed the other. Still unoccupied, the Skylab was stricken with the loss of the heat shield and sunlight beat mercilessly on the lab's sensitive skin. Internal temperatures soared, rendering the station uninhabitable, threatening foods, medicines, films, and experiments. This image, taken during a fly-around inspection by the Skylab-2 crew, shows a crippled Skylab in orbit. The crew found their home in space to be in serious shape; the heat shield gone, one solar wing gone, and the other jammed. The Marshall Space Flight Center (MSFC) developed, tested, rehearsed, and approved three repair options. These options included a parasol sunshade and a twin-pole sunshade to restore the temperature inside the workshop, and a set of metal cutting tools to free the jammed solar panel.

1973-01-01

281

Toxic torts and environmental law: Recent developments  

SciTech Connect

This article describes recent developments in environmental law including the following: in Toxic tort issues: standards for expert testimony; punitive damages; preemption; failure to warn and strict liability; the unavoidably unsafe defense; in Hazardous waste issues: joint and several liability; petroleum exclusion; recoverable costs; causation; owner or operator and successor liability; contribution; commerce; RCRA land bar; criminal conviction.

Mahoney, W.F. [ed.; Murphy, J.; Cross, A. [Segal, McCambridge, Singer & Mahoney, Ltd., Chicago, IL (United States)] [and others

1994-12-31

282

Nonequilibrium statistical theory of damage fracture for quasi-brittle materials  

Microsoft Academic Search

A nonequilibrium statistical theory of damage fracture is developed on the foundation of nonequilibrium statistical theory of fracture. The evolution of microcracks is regarded as the elementary process of damage to the material structure. The failure probability of the material due to the evolution of microcracks under the action of applied load may be defined as the damage variable. By

Xing Xiusan

1997-01-01

283

Human rights and health law.  

PubMed

Important statutory and common law developments are changing the landscape of health law in Australia. Human rights considerations are formally included amongst the factors to be applied in the interpretation of statutory provisions and evaluating the lawfulness of actions on the part of government instrumentalities. The Human Rights Act 2004 (ACT) and the Charter of Human Rights and Responsibilities Act 2006 (Vic) create limited bills of rights at State/Territory level in two Australian jurisdictions. Although neither is entrenched, they have the potential to make it more difficult for government to promulgate laws that are inconsistent with human rights, as defined. They will have important repercussions for the evolution of health law in these jurisdictions. The decision of Royal Women's Hospital v Medical Practitioners Board (Vic) [2006] VSCA 85 by the Victorian Court of Appeal has also provided a legitimation for parties to incorporate human rights perspectives in submissions about the interpretation of statutory provisions where health rights are in conflict. PMID:16937776

Freckelton, Ian

2006-08-01

284

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

285

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

286

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

287

Cumulative creep damage for unidirectional composites under step loading  

NASA Astrophysics Data System (ADS)

The creep lifetime prediction of unidirectional composite materials under step loading, based on constant loading durability diagram, is analyzed for the two-step creep loading condition. For this purpose different nonlinear cumulative-damage laws are revisited and applied to predict creep lifetime. One possible approach to accounting for damage accumulation is provided by the continuum-damage mechanics (CDM). However, the CDM lifetime expression obtained for constant loading condition presents some drawbacks. Specifically, the upper stress range is not accommodated by CDM form. A modification of CDM is proposed, forcing the CDM to capture the short-term creep failure. It is proven that this modified CDM (MCDM) does not yield the same predictions as the Linear Cumulative-damage law (Miner's law). Predictions obtained from the nonlinear cumulative-damage laws are compared against synthetic lifetime generated by a micromechanical model that simulates unidirectional composites under two-step creep loading condition. Comparable deviations from Miner's law are obtained by the nonlinear cumulative-damage laws.

Guedes, Rui Miranda

2012-11-01

288

Power laws, Pareto distributions and Zipf's law  

Microsoft Academic Search

When the probability of measuring a particular value of some quantity varies inversely as a power of that value, the quantity is said to follow a power law, also known variously as Zipf's law or the Pareto distribution. Power laws appear widely in physics, biology, earth and planetary sciences, economics and finance, computer science, demography and the social sciences. For

Mej Newman

2005-01-01

289

Inelastic deformation and damage at high temperature  

Microsoft Academic Search

Combined experimental and theoretical investigations into the inelastic deformation and damage behavior of engineering alloys at elevated temperatures are being pursued. The analysis of previously performed strain rate change and relaxation tests on modified 9Cr-1Mo steel showed the need for inclusion of a recovery of state term in the growth laws for the state variables of the viscoplasticity theory based

E. Krempl

1992-01-01

290

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.

291

Multiple Equilibria in an Optimal Control Model for Law Enforcement  

Microsoft Academic Search

In this paper, Becker's (1968) economic approach to crime and punishment is extended by including intertemporal aspects. We an- alyze a one-state control model to determine the optimal dynamic trade-o between damages caused by oenders and law enforcement expenditures. By using Pontryagin's maximum principle we obtain interesting insight into the dynamical structure of optimal law en- forcement policies. It is

Gustav Feichtinger; Gernot Tragler

292

The Distinction between Civil and Criminal Law: A Lesson Plan for High School Law-Related Educators To Support "Understanding the Federal Courts."  

ERIC Educational Resources Information Center

The O. J. Simpson trials taught much of the United States a basic lesson in the difference between criminal law and civil law. Many students learn in their government classes that a person cannot be tried twice for the same crime. A person found innocent in a criminal trial, however, can be sued under civil law procedures for damages. It is…

Administrative Office of the United States Courts, Washington, DC.

293

Sea shipment of Japanese plutonium under international law  

SciTech Connect

The Japanese government`s shipment of plutonium from France to Japan raises a number of significant questions under international law. The first shipment, which began in November 1992 on the Akatsuki Maru, violated international law in several respects. This article analyzes the international law that governs these shipments, focusing on the rules that govern navigation on the high seas and exclusive economic zones, territorial seas, and international straits, and also addresses the question of liability for damage. 281 refs.

Van Dyke, J.M. [Univ. of Hawaii, Honolulu, HI (United States)

1993-10-01

294

New evolution equations for turbulent boundary layers  

Microsoft Academic Search

Perry, Marusic & Li (1994) (Phys. Fluids, vol. 6(2) part 2) initially developed a mathematical framework for computing the evolution of boundary layers using classical similarity laws such as Prandtl's law of the wall and Coles' law of the wake together with the momentum integral and differential equations. It was found that these equations show that there are 4 parameters

A. E. Perry

1998-01-01

295

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 material’s 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

296

Subsidence: an emerging area of the law  

SciTech Connect

This Note surveys various legal theories courts could employ to compensate property owners injured by subsidence caused by groundwater pumping. Many courts have clouded the subsidence issue by applying water law to determine liability. Dissatisfied with the results of applying water law to subsidence, the Texas Supreme Court held, in the landmark Friendswood decision, that negligence would be a cause of action to redress future subsidence. The best theory of liability for subsidence damage, however, is loss of subjacent support. The prevailing rule under the law of support is that the defendant is strictly liable for damage resulting from withdrawal of support. The Restatement and several cases have finally recognized that there is no valid distinction between withdrawal of solid and fluid substances for purposes of imposing strict liability under subjacent support principles. Since subsidence may result from groundwater pumping even in the absence of negligence, strict liability is superior to a negligence theory. Unlike any water law theory, the law of support recognizes that the injury is to rights in land rather than to water rights. Until legislatures respond to the problem, adherence to the law of subjacent support is the best approach to internalizing the costs of subsidence.

Morris, J.

1981-01-01

297

Loi d'évolution de l'endommagement pour la prise en compte de l'adoucissement dans les milieux élastomères chargésDamage evolution law for the study of stress-softening in reinforced rubber-like materials  

NASA Astrophysics Data System (ADS)

An experimental study on oligo-cyclic fatigue of rubber-like materials submitted to tension test in large deformation, to constant amplitude of loadings, brings to the fore that the stress during the loading, at a given cycle, is always smaller than during the previous cycle. These tests highlight that this phenomenom, called stress-softening, depends on the maximal stretch and on the number of cycles to which the materials has been submitted. A model, taking into account these two parameters is proposed and experimental validations are proposed. To cite this article: M. Brieu et al., C. R. Mecanique 332 (2004).

Brieu, Mathias; Gentot, Laëtitia; Mesmacque, Gérard

2004-01-01

298

An elastic plastic damage formulation for concrete: Application to elementary tests and comparison with an isotropic damage model  

Microsoft Academic Search

Pure elastic damage models or pure elastic plastic constitutive laws are not totally satisfactory to describe the behaviour of concrete. They indeed fail to reproduce the unloading slopes during cyclic loading which define experimentally the value of the damage in the material. When coupled effects are considered, in particular in hydro-mechanical problems, the capability of numerical models to reproduce the

Ludovic Jason; Antonio Huerta; Gilles Pijaudier-Cabot; Shahrokh Ghavamian

2006-01-01

299

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

300

A Micropillar Compression Methodology for Ductile Damage Quantification  

NASA Astrophysics Data System (ADS)

Microstructural damage evolution is reported to influence significantly the failures of new high-strength alloys. Its accurate quantification is, therefore, critical for (1) microstructure optimization and (2) continuum damage models to predict failures of these materials. As existing methodologies do not fulfill the requirements, there is an active search for an accurate damage quantification methodology. In this article, a new, micropillar, compression-based methodology is presented, whereby damage evolution can be quantified successfully through the degradation of the modulus caused by previous deformation.

Tasan, C. C.; Hoefnagels, J. P. M.; Geers, M. G. D.

2012-03-01

301

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

302

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

303

Students and the Law.  

ERIC Educational Resources Information Center

Designed as a practical approach to the study of law, this publication offers seven lesson plans focusing on legal topics that have potential significance to high school students preparing to enter the world of work. Lesson plans address the following topics: minors and the law, automobile insurance, employment law, sports and the law, computer…

South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

304

Career Goals: Law, Economics,  

E-print Network

(SPECIALISATION) EUROPEAN AND INTERNATIONAL TAX LAW (SPECIALISATION) MASTER EN DROIT EUROPÉEN ­ LL.M. 15 EUROPEAN on CIS during last semester) 4. European and International Tax Law 5. European Private Law 6. GeneralCareer Goals: Law, Economics, Finance and Innovation ­ Our Masters' Degrees #12;2 3 CONTENT

van der Torre, Leon

305

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

306

A damage model for orthotropic metals  

NASA Astrophysics Data System (ADS)

The paper describes a ductile damage model for orthotropic metals. The ductile failure of metals is an important phenomena in crashworthiness, impact and shock problems, and therefore must be considered in structural simulations. The model is based on an orthotropic damage matrix which is incorporated in the constitutive equations for stress update and provides degradation of material properties. The evolution of the damage matrix assumes the growth and coalescence of voids. The implementation of the model for both continuum and shell elements is discussed. Finally the model is demonstrated on test problems.

Campbell, J. C.; Vignjevic, R.; Mirkovic, J.

2006-08-01

307

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)

Doran, D. G.

1980-02-01

308

America's Anti-Evolution Movement  

ERIC Educational Resources Information Center

Evolution is the cornerstone of biology and one of the most powerful, exciting, and well-supported laws in modern science. Evolution transforms biology from a collection of unrelated observations and definitions into a coherent discipline that, among other things, helps people understand life's history and predict answers to important research…

Moore, Randy

2002-01-01

309

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

310

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

311

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

312

Law enforcement surveillance in the network society  

Microsoft Academic Search

We study the evolution of telecommunications technology and the challenges to surveillance faced by law enforcement agencies. We focus on surveillance history in the United States. US government surveillance will have an increasing impact on the global civil society because of the globalization of packet-based communication networks-as a great deal of international traffic travels across American network wires. The bandwidth

Serena Chan; L. Jean Camp

2002-01-01

313

Anti-Corn-Law agitations in Scotland, with particular reference to the Anti-Corn-Law League   

E-print Network

The Corn Laws and the movement for their repeal were both indigenous products of Scotland, although even in the eighteenth century, less intrinsically Scottish than the polemics of the debate would suggest. The evolution of aim, attitude...

Cameron, Kenneth John

1971-01-01

314

Nottingham Law School Topics in Environmental Law  

E-print Network

on the Graduate School website Entry requirement A good UK honours degree (or equivalent) in a related subjectNottingham Law School Topics in Environmental Law Projects within the following themes contact Professor David Ong ­ david.ong@ntu.ac.uk or the School Postgraduate Research Tutor, Professor

Evans, Paul

315

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

316

Evolution Model of Scientific and Technical Innovation  

Microsoft Academic Search

Research on evolution law of scientific and technical innovation is significant for China to build innovation-oriented country. An evolution model of scientific and technical innovation is established according to the research from the perspective of system, evolution and case demonstration. This model contains innovation stage, innovation form, innovation mission, development trend of innovation and the relation among them. The essential

Wang Anyou; Liang Yang; Guo Lin

2008-01-01

317

Anisotropic damage effects in masonry walls  

NASA Astrophysics Data System (ADS)

This paper refers to the characterization of plane masonry behaviour under the assumption of plane stress. Masonry may be seen as a two-phase (bricks and mortar) periodic anisotropic material with complex macroscopic behaviour due to the possible occurrence of cracking in each of the phases. Non-linear constitutive equations have thus to be used in order to realistically represent masonry structures. Most existing macroscopic models defined for such materials are by essence phenomenological. This leads to weakly motivated frameworks and rather complex models, especially if one wants to account for material symmetry evolution due to cracking. The aim of this paper is to identify a simple set of damage mechanics variables for the constituents that could be used in homogenization procedures to infer the overall behaviour of the material from its mesostructural features (geometrical arrangement and mechanical properties of the constituents). Based on unit cell computations, it is shown that scalar damage mesomodels allow to obtain realistic damage patterns encountered in experiments. Results suggest that at the meso-scale, it is possible to use a scalar damage model for the individual phases which naturally leads to the desired anisotropy evolution into the macroscopic descriptions. This macroscopic anisotropy evolution is illustrated using a numerical homogenization procedure to identify the degraded stiffness associated to damage patterns. The influence of variations in the constituent characteristics is also correctly captured as illustrated for some of the loading schemes.

Massart, T.; Bouillard, P.; Geers, M. G. D.; Peerlings, R. H. J.

2003-03-01

318

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.

319

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

320

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

321

Women's law: methods, problems, values  

Microsoft Academic Search

The five areas of women's law that I have chosen to focus — money law, housewives' law, paid-work law, criminal law and birth law — represent different coordinating perspectives on women's legal position. These perspectives could certainly have been supplemented by others, for example, discrimination law. The feminist perspective can also be used in several traditional areas of legal science

Tove Stang Dahl; Karl Johans

1987-01-01

322

The damage mechanics of brittle solids in compression  

Microsoft Academic Search

The development of microcrack damage in brittle solids in compression is analyzed, using a simple model. The model is developed from recent detailed analysis of the initiation, propagation and linkage of microfractures from pre-existing cracks, voids, or other inhomogeneities. It describes the evolution of damage with strain and from it a criteria for failure can be established. The results are

M. F. Ashby; C. G. Sammis

1990-01-01

323

Laws, Morals and Politics  

E-print Network

in social science" of maintaining that certain "criteria of identity" are visible only after certain "basic reasons"—intrasystemic rationales—are accepted by the observer. From the position of maintaining some things as external to law, both Kelsen... across the entire legal system. And Dworkin further re­ jects the idea that the "internal criteria of law" can ever be precisely formulated, so that a singular line of demarcation can be drawn to differentiate "this as law" from "this as not law...

Burkhardt, Robert J.

324

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

325

Teaching Law and Geography.  

ERIC Educational Resources Information Center

Suggests the need for a law and geography course to prepare future geographers to contribute to implementation of the law. Proposes a course outline, including an introduction, major existing research areas, and exploration of developing new research areas combining law and geography. Stresses the importance of social and environmental data in…

Journal of Geography, 1991

1991-01-01

326

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

327

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.

328

LAW, RELIGION & EDUCATION  

E-print Network

LAW, RELIGION & EDUCATION: Religious Freedom in the Sphere of Education 8th & 9th October 2010 A two-day conference organised by The Institute of Global Law at UCL and Maison Française d. The Conference will examine the relationships between "Law, Religion and Education", addressing the accommodation

Saunders, Mark

329

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.

330

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

331

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

332

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.

David Stern

333

Characteristics of Creep Damage for 60Sn40Pb Solder Material  

Microsoft Academic Search

This paper presents a viscoplasticity model taking into account the effects of change in grain or phase size and damage on the characterization of creep damage in 60Sn-40Pb solder. Based on the theory of damage mechanics, a two-scalar damage model is developed for isotropic materials by introducing the free energy equivalence principle. The damage evolution equations are derived in terms

Y. Wei; C. L. Chow; H. E. Fang; M. K. Neilsen

1999-01-01

334

A theoretical model of grainsize evolution during deformation  

NASA Astrophysics Data System (ADS)

Lithospheric shear localization, as occurs in the formation of tectonic plate boundaries, is often associated with diminished grainsize (e.g., mylonites). Grainsize reduction is typically attributed to dynamic recrystallization; however, theoretical models of shear-localization arising from this hypothesis are problematic since (1) they require the simultaneous action of two exclusive creep mechanisms (diffusion and dislocation creep), and (2) the grain-growth ("healing") laws employed by these models are derived from static grain-growth or coarsening theory, although the shear-localization setting itself is far from static equilibrium. We present a new first-principles grained-continuum theory which accounts for both coarsening and damage-induced grainsize reduction. Damage per se is the generic process for generation of microcracks, defects, dislocations (including recrystallization), subgrains, nucleii and cataclastic breakdown of grains. The theory contains coupled statistical grain-scale and continuum macroscopic components. The grain-scale element of the theory prescribes both the evolution of the grainsize distribution, and a phenomenological grain-growth law derived from non-equilibrium thermodynamics; grain-growth thus incorporates the free energy differences between grains, including both grain-boundary surface energy (which controls coarsening) and the contribution of deformational work to these free energiesconservation and positivity of entropy production provide the phenomenological law for the statistical grain-growth law. We identify four potential mechanisms that affect the distribution of grainsize; two of them conserve the number of grains but change their relative masses and two of them change the number of grains by sticking them together or breaking them. In the limit of static equilibrium, only the two mechanisms that increase the average grainsize are allowed by the second law of thermodynamics. The first one is a diffusive mass transport from small grains to large grains that captures the essential component of normal grain-growth theories. The second one is the aggregation of grains. With the inclusion of nonstatic/nonequilibrium conditions, the theory predicts two mechanisms for which the thermodynamic requirement of entropy positivity always imposes large grains to shrink and small ones to grow. A first damage mechanism opposite to diffusion, tends to homogenize the distribution of grainsize around its initial average grainsize. A second damage mechanism favors the creation of small grains by division of larger grains. This second mechanism reduces the average grainsize with time. The competition between the two coarsening mechanisms, the damage-induced grain homogenization and the damage-induced grain reduction controls the general evolution of the grainsize population. Under uniform and constant shear, and assuming than grains cannot stick together, the average grainsize is related to the energy dissipated during the deformation (in agreement with Austin and Evans, 2007). The prediction of this theory fits satisfactorily with the available observations and we will discuss the implications of this model for large scale geodynamics.

Ricard, Y.; Bercovici, D.; Rozel, A.

2007-12-01

335

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

336

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

337

Constitutive model of micromechanical damage to predict reduction in stiffness of a fatigued SMC composite  

NASA Astrophysics Data System (ADS)

Elastic behavior of sheet molding compound (SMC) composites with a given orientational distribution of fibers under cyclic loading is investigated herein. Fatigue tests were carried out over various strain ranges. During each test, evolution of Young’s modulus was measured and the composite was analyzed using scanning electron microscopy. Observations revealed the principal form of degradation to be matrix fiber debonding. A constitutive model that takes into account the reduction of overall elastic properties, i.e., Young’s modulus, was developed. This model uses a Mori-Tanaka mean field approach coupled with a micromechanical damage law. The energetic failure criterion and the failure probability are functions of local shear and normal stresses calculated at each point of the interface of each fiber family. A procedure for identifying the most appropriate material parameters is described in detail. The proposed model agrees well with the experimental results.

Ben Cheikh Larbi, A.; Sidhom, H.; Sai, K.; Baptiste, D.

2006-10-01

338

Three Laws in Darwinian Evolutionary Theory  

NASA Astrophysics Data System (ADS)

Recent works to formulate laws in Darwinian evolutionary dynamics will be discussed. Specifically, three laws which form a consistent mathematical framework for the evolutionary dynamics in biology will be spelt out. The second law is most quantitative and is explicitly expressed in the unique form of a stochastic differential equation. Salient features of Darwinian evolutionary dynamics are captured by this law: the probabilistic nature of evolution, ascendancy, and the adaptive landscape. Four dynamical elements are introduced in this formulation: the ascendant matrix, the transverse matrix, the Wright evolutionary potential, and the stochastic drive. The first law may be regarded as a special case of the second law. It gives the reference point to discuss the evolutionary dynamics. The third law describes the relationship between the focused level of description to its lower and higher ones, and defines the dichotomy of deterministic and stochastic drives. It is an acknowledgement of the hierarchical structure in biology. A new interpretation of Fisher's fundamental theorem of natural selection is provided in terms of the F-Theorem. Ref. P. Ao, Physics of Life Reviews 2 (2005) 117-156.

Ao, Ping

2006-03-01

339

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 Mendel’s experiments and on Darwin’s 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

340

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 in Law School Admissions Panel epresentatives will discuss the law school admissions process and talk/133 Light refreshments will be served Law School Admissions Panel epresentatives will discuss the law school

Brinkmann, Peter

341

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

342

Ulnar nerve damage (image)  

MedlinePLUS

... elbow because of elbow fracture or dislocation. The ulnar nerve is near the surface of the body where it crosses the elbow, so prolonged pressure on the elbow or entrapment of the nerve may cause damage. Damage to ...

343

Biological damage to fuels  

Microsoft Academic Search

This article reports on an investigation of the damage to fuels caused by microorganisms in various climatic zones. Fuel samples were taken from aircraft, ships, and tractors. The results indicate that the most susceptible to biological damage are diesel fuels in shipboard equipment operating in regions with a warm, moist (tropical) climate. The biological damage of fuels can lead to

V. B. Skribachilin; E. A. Lapteva; L. K. Mikhailova

1984-01-01

344

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

345

Nonlocal anisotropic damage model and related computational aspects for quasi-brittle materials  

Microsoft Academic Search

A three-dimensional damage model with induced damage anisotropy is proposed for quasi-brittle materials such as concrete. The thermodynamics framework is used, considering then a single second-order tensorial damage variable whatever the intensity and the sign of the loading. The quasi-unilateral conditions of micro-cracks closure are written on the hydrostatic stress only. Altogether with the consideration of damage laws ensuring a

R. Desmorat; F. Gatuingt; F. Ragueneau

2007-01-01

346

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.; Réthoré, J.; Bung, H.; Suffis, A.

2006-08-01

347

Plasticity-damage couplings in titanium  

NASA Astrophysics Data System (ADS)

At room temperature, titanium materials display deformation and failure properties that are quite different from that of typical materials with cubic crystalline structure (aluminium, steels, etc). Rolled or extruded products exhibit a strong anisotropy and very pronounced difference in yielding and work-hardening evolution between tension and compression loadings. In this paper, a macroscopic elastic/plastic model that accounts for the key features of the plastic deformation of Ti, in particular the distortion of the yield surface induced by texture evolution is presented. Comparison with data demonstrates that the model predicts with accuracy the plastic response for a variety of loading conditions. Furthermore, it is shown that the model can be extended such as to incorporate damage. In contrast to existing approaches, the plasticity-damage couplings are deduced and not postulated. Hence, all material parameters have a clear physical significance, being related to plastic properties that can be determined from few simple mechanical tests. The new model predicts that in titanium materials damage accumulation is strongly influenced by the anisotropy and asymmetry in plastic flow. Moreover, it is shown that under uniaxial tension, the porosity evolution should be much slower than in materials with plastic flow obeying the classical von Mises criterion, and that the succession of damage events leading to failure should also be markedly different.

Cazacu, Oana; Baudard, Benoit Revil

2013-12-01

348

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

349

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

2014-09-26

350

Power-Law Entropic Corrections to Newton's Law and Friedmann Equations  

E-print Network

A possible source of black hole entropy could be the entanglement of quantum fields in and out the horizon. The entanglement entropy of the ground state obeys the area law. However, a correction term proportional to a fractional power of area results when the field is in a superposition of ground and excited states. Inspired by the power-law corrections to entropy and adopting the viewpoint that gravity emerges as an entropic force, we derive modified Newton's law of gravitation as well as the corrections to Friedmann equations. In a different approach, we obtained power-law corrected Friedmann equation by starting from the first law of thermodynamics at apparent horizon of a FRW universe, and assuming that the associated entropy with apparent horizon has a power-law corrected relation. Our study shows a consistency between the obtained results of these two approaches. We also examine the time evolution of the total entropy including the power-law corrected entropy associated with the apparent horizon together with the matter field entropy inside the apparent horizon and show that the generalized second law of thermodynamics is fulfilled in a region enclosed by the apparent horizon.

Ahmad Sheykhi; Seyed Hossein Hendi

2011-08-07

351

Madhavi Sunder Professor of Law  

E-print Network

Madhavi Sunder Professor of Law UC Davis School of Law http://www.law on intellectual property considers this law from the standpoint of law and economics. Under this conventional. In this highly original book Madhavi Sunder calls for a richer understanding of intellectual property law

352

The Puzzle of Martial Law  

Microsoft Academic Search

Martial law is thought to be not a complete absence of law, nor a special kind of law – a scheme of legal regulation – but, rather, an absence of law prescribed by law under the concept of necessity – a legal black hole, but one created, perhaps even in some sense bounded, by law. A.V. Dicey claimed that martial

David Dyzenhaus

2009-01-01

353

A Physically Based Cumulative Damage Formalism  

NASA Astrophysics Data System (ADS)

A general cumulative damage methodology is derived from the basic relation specifying crack growth rate (increment) as a power law function of the stress intensity factor. The crack is allowed to grow up to the point at which it becomes unstable, thereby determining the lifetime of the material under the prescribed stress program. The formalism applies for the case of creep to failure under variable stress history as well as for cyclic fatigue to failure under variable stress amplitude history. The formulation is calibrated by the creep rupture lifetimes at constant stress or the fatigue cycle lifetimes at constant stress amplitude. No empirical (non-physical) parameters are involved in the basic formulation;everything is specified in terms of experimentally determined quantities. Several examples are given showing the inadequacy of Linear Cumulative Damage while the present nonlinear damage accumulation method overcomes these deficiencies. The present method is extended to admit probabilistic conditions.

Christensen, Richard M.

354

Macrothermodynamics of Biological Evolution:  

NASA Astrophysics Data System (ADS)

The author sets forth general considerations pertaining to the thermodynamic theory of biological evolution and the aging of living organisms. It becomes much easier to comprehend the phenomenon of life scrutinizing the formation of structural hierarchies of biological matter applying different temporal scales. These scales are 'identified' by nature itself, and this is reflected in the law of temporal hierarchies. The author discusses some misunderstandings in thermodynamics and evolutionary biology. A simple physicochemical model of biological evolution and the development of living beings is proposed. The considered theory makes it possible to use physicochemical evaluations to develop effective anti-aging diets.

Gladyshev, Georgi P.

355

A high accuracy femto-/picosecond laser damage test facility dedicated to the study of optical thin films  

SciTech Connect

A laser damage test facility delivering pulses from 100 fs to 3 ps and designed to operate at 1030 nm is presented. The different details of its implementation and performances are given. The originality of this system relies the online damage detection system based on Nomarski microscopy and the use of a non-conventional energy detection method based on the utilization of a cooled CCD that offers the possibility to obtain the laser induced damage threshold (LIDT) with high accuracy. Applications of this instrument to study thin films under laser irradiation are presented. Particularly the deterministic behavior of the sub-picosecond damage is investigated in the case of fused silica and oxide films. It is demonstrated that the transition of 0-1 damage probability is very sharp and the LIDT is perfectly deterministic at few hundreds of femtoseconds. The damage process in dielectric materials being the results of electronic processes, specific information such as the material bandgap is needed for the interpretation of results and applications of scaling laws. A review of the different approaches for the estimation of the absorption gap of optical dielectric coatings is conducted and the results given by the different methods are compared and discussed. The LIDT and gap of several oxide materials are then measured with the presented instrument: Al{sub 2}O{sub 3}, Nb{sub 2}O{sub 5}, HfO{sub 2}, SiO{sub 2}, Ta{sub 2}O{sub 5}, and ZrO{sub 2}. The obtained relation between the LIDT and gap at 1030 nm confirms the linear evolution of the threshold with the bandgap that exists at 800 nm, and our work expands the number of tested materials.

Mangote, B.; Gallais, L.; Zerrad, M.; Lemarchand, F.; Gao, L. H.; Commandre, M.; Lequime, M. [Institut Fresnel, CNRS, Aix-Marseille Universite, Ecole Centrale Marseille, Campus de St Jerome, 13013 Marseille (France)

2012-01-15

356

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

357

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

358

Simulation of the elementary damage accumulation kinetics in loaded materials  

NASA Astrophysics Data System (ADS)

The evolution of an ensemble of elementary-damage clusters is considered using a probabilistic cellular automaton, and the characteristics of the time series of the number of elementary damages and the number of elementary-damage clusters are studied. The transition of the autocorrelation function of the time series of the number of elementary damages to a negative-correlation region is shown to correspond to the transition of the evolution of an ensemble of clusters to the stage of coalescence. The autocorrelation function of the time series of the number of elementary damages agrees qualitatively with the experimental behavior of the autocorrelation functions of the number of electromagnetic- and light-emission pulses in loaded materials.

Alekseev, D. V.; Kazunina, G. A.

2010-04-01

359

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 commonâ€law countries generally have the strongest, and french civil law countries the weakest, legal protections of investors, with Germanâ€-and Scandinavianâ€-civilâ€law 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

360

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.

John Pratte

361

Zipf's law, power laws, and maximum entropy  

E-print Network

Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines - from astronomy to demographics 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 article I argue that the 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

2012-01-01

362

Zipf's law, power laws, and maximum entropy  

E-print Network

Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines - from 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 article I argue that the 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.

Matt Visser

2013-04-07

363

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

364

Bullying Policies and Laws  

MedlinePLUS

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

365

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.

366

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.

367

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.

368

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

369

A damage mechanics model for uniaxial deformation of ice  

SciTech Connect

A one-dimensional stress-strain relationship is developed for pure polycrystalline ice subjected to uniaxial compression. The model is based on the continuous damage theories and includes the effects of elastic, plastic and brittle deformation mechanisms. A damage law for ice is established based on a statistical model for internal microfracture. Quantitative results are presented by directly relating the formation of internal cracks to published acoustic emission response of ice samples subjected to compression.

Karr, D.G.

1985-09-01

370

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

371

Good Enough V&V for Simulations: Some Possibly Helpful Thoughts from the Law & Ethics of Commercial Software  

E-print Network

rule in American maritime law for allocating damages when a barge breaks free and the bargee (a personGood Enough V&V for Simulations: Some Possibly Helpful Thoughts from the Law & Ethics of Commercial will address the intersection of modeling and simulation VV&A with civil law, suggesting a style of cost

372

RANDOM EVOLUTION IN MASSIVE GRAPHS William Aiello  

E-print Network

properties for such massive and dynamic graphs as the Internet and the World Wide Web? For example stages for the study of several massive, dynamic graphs such as the World Wide Web. The starting point the history and previous work on power law graphs. Then we give four evolution models for generating power law

Lu, Linyuan Lincoln

373

EOS Laser Atmosphere Wind Sounder (LAWS) investigation  

NASA Technical Reports Server (NTRS)

In this final report, the set of tasks that evolved from the Laser Atmosphere Wind Sounder (LAWS) Science Team are reviewed, the major accomplishments are summarized, and a complete set of resulting references provided. The tasks included preparation of a plan for the LAWS Algorithm Development and Evolution Laboratory (LADEL); participation in the preparation of a joint CNES/NASA proposal to build a space-based DWL; involvement in the Global Backscatter Experiments (GLOBE); evaluation of several DWL concepts including 'Quick-LAWS', SPNDL and several direct detection technologies; and an extensive series of system trade studies and Observing System Simulation Experiments (OSSE's). In this report, some of the key accomplishments are briefly summarized with reference to interim reports, special reports, conference/workshop presentations, and publications.

1996-01-01

374

Laws of Energy Gradient for Instabilities  

E-print Network

Transition to turbulence is due to the instability of a laminar flow subject to a disturbance. This complicated problem can be explained using a new proposed energy gradient theory in our previous study. This theory is extended to the instability of fluid material systems in this study. The instability of fluid material systems may lead to the evolution of natural environments and the occurrence of catastrophic events in the world. To better describe these phenomena and to understand the physical mechanism behind them are very important. In order to more generally describe the instability of fluid material systems, laws of energy gradient are summarized for static and motion systems, respectively. These laws could be applicable to various flow problems and material systems. Examples are shown that many events in the world could be explained using these laws.

Hua-Shu Dou

2005-06-25

375

Newton's 3 Laws of Motion  

NSDL National Science Digital Library

Learn about Sir Isaac Newton's 3 laws of motion and see how you experience these laws every day! Today you are going to be learning about Sir Isaac Newton's three laws of motion. A. Newton s 3 Laws of Motion On this first site click on the different links and learn about the following: About Sir Isaac Newton The 1st law of motion The 2nd law of motion The 3rd law of motion Make sure to write down what ...

Miss Friske

2010-04-21

376

Power Laws are Disguised Boltzmann Laws  

NASA Astrophysics Data System (ADS)

Using a previously introduced model on generalized Lotka-Volterra dynamics together with some recent results for the solution of generalized Langevin equations, we derive analytically the equilibrium mean field solution for the probability distribution of wealth and show that it has two characteristic regimes. For large values of wealth, it takes the form of a Pareto style power law. For small values of wealth, w<=wm, the distribution function tends sharply to zero. The origin of this law lies in the random multiplicative process built into the model. Whilst such results have been known since the time of Gibrat, the present framework allows for a stable power law in an arbitrary and irregular global dynamics, so long as the market is ``fair'', i.e., there is no net advantage to any particular group or individual. We further show that the dynamics of relative wealth is independent of the specific nature of the agent interactions and exhibits a universal character even though the total wealth may follow an arbitrary and complicated dynamics. In developing the theory, we draw parallels with conventional thermodynamics and derive for the system some new relations for the ``thermodynamics'' associated with the Generalized Lotka-Volterra type of stochastic dynamics. The power law that arises in the distribution function is identified with new additional logarithmic terms in the familiar Boltzmann distribution function for the system. These are a direct consequence of the multiplicative stochastic dynamics and are absent for the usual additive stochastic processes.

Richmond, Peter; Solomon, Sorin

377

New Evolution Equations for Turbulent Boundary Layers in Arbitrary Pressure Gradients  

Microsoft Academic Search

Perry, Marusic & Li (1994) initially developed a mathematical framework for computing the evolution of boundary layers using classical similarity laws such as Prandtl's law of the wall and Coles' law of the wake together with the momentum integral and differential equations. It was found that these equations show that there are 4 parameters which control the streamwise evolution of

A. E. Perry; I. Marusic; M. B. Jones

1997-01-01

378

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

379

Essentials of general average: A synoptic overview of an ancient maritime law  

Microsoft Academic Search

This article provides a synoptic overview of the concept of general average which is one of the saving acts in maritime law.\\u000a Its principles were entrenched in the Roman law which acknowledged its origins being rooted in the Sea Law of Rhodes. Its\\u000a evolution as customary law through the medieval maritime codes of the Mediterranean region is also traced in

Proshanto K. Mukherjee

2007-01-01

380

Combinatorics of Conservation Laws  

Microsoft Academic Search

Conservation laws in physics are numerical invariants of the dynamics of a system. This article concerns conservation laws in a fictitious universe of a cellular automaton. We give an overview of the subject, with particular attention to problems of combinatorial flavor.

Jarkko Kari; Siamak Taati

381

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

382

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

383

Pop Goes the Law  

ERIC Educational Resources Information Center

The Law School Admission Council recently reported that applications were heading toward a 30-year low, reflecting, as a "New York Times" article put it, "increased concern over soaring tuition, crushing student debt, and diminishing prospects of lucrative employment upon graduation." Since 2004 the number of law-school applicants has dropped from…

Harper, Steven J.

2013-01-01

384

School of Law Scholarships  

E-print Network

School of Law Scholarships Complete Scholarship Name Application Deadline Date Contact Name Contact This scholarship was created in March 2010 by the American College of Trial Lawyers to support programs of Admissions 803.777.6605 usclaw@law.sc.edu Andrew J. Savage Scholarship Endowment Fund The Andrew J. Savage

Almor, Amit

385

Ohm's Law 2  

NSDL National Science Digital Library

In this extension to the Ohm's Law I activity, students observe just how much time it takes to use up the "juice" in a battery, and if it is better to use batteries in series or parallel. This extension is suitable as a teacher demonstration and may be started before students begin work on the Ohm's Law I activity.

K-12 Outreach Office,

386

Law Related Education.  

ERIC Educational Resources Information Center

This journal edition focuses upon the many resources for teachers to draw upon in order to infuse law-related education (LRE) into their classrooms. Isidore Starr explains the reasons behind the LRE movement, while Mabel McKinney-Browning describes the existing American Bar Association's programs in LRE. Judith Zimmer covers the Street Law…

Maslow, R., Ed.; Kirchgaessner, R., Ed.

1989-01-01

387

Indian Law Enforcement History.  

ERIC Educational Resources Information Center

Written as a tribute to American Indian law enforcement officers and the Indian Criminal Justice System, this monographh details the history of the legislative, judicial, financial, and cultural problems associated with the development of Indian law enforcement. Citing numerous court cases, pieces of legislation, and individual and organizational…

Etheridge, David

388

The Corporate Law Curriculum  

ERIC Educational Resources Information Center

On the premise that corporate counsel must be an able diagnostician before he can focus on highly specialized and interrelated issues of business law, the author suggests an approach to corporate law curriculum in which the basic course balances the quality and quantity of material designed to create the needed sensitivity. (JT)

Mofsky, James S.

1976-01-01

389

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

390

Law and Marine Science  

ERIC Educational Resources Information Center

The University of Delaware Marine Studies has implemented courses in coastal zone law and policy and maritime law. The courses attempt to integrate the scientist's or engineer's work with public policy formation. The program emphasizes historical and current issues and the economic, cultural, and political forces operating in decision-making…

Bockrath, Joseph

1976-01-01

391

Science and the Law.  

ERIC Educational Resources Information Center

Explaines the role of the Carnegie Commission which was formed to explore the relationship between the disciplines of science, technology, and the law. Discusses concerns about the individual right of privacy in projects such as the Human Genome Project. Focuses on the panel on Science, Technology, and Law which was established in 1999. (YDS)

Kennedy, Donald; Merrill, Richard A.

2000-01-01

392

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

393

Prostitution Laws in Australia  

Microsoft Academic Search

The subject of prostitution has long vexed criminal justice authorities in Australia, as in most other countries throughout the world. Law-makers are faced with the onerous task of attempting to appease the conflicting demands of various segments of society. On the one hand law-makers in Australia wish to uphold the principles of a liberal democratic society by allowing consenting adults

Susan Pinto; Paul Wilson

394

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 (2Ls/3Ls): 49694 Instructor: Robert D. Infelise Email: rinfelise@law.berkeley.edu Location: 115 Boalt Time: M, Tues, W 2:05-3:10 Texts: (R) Class Reader (M) Jeffrey G. Miller & Craig N. Johnston, The Law

Kammen, Daniel M.

395

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 (2Ls/3Ls): 49694 Instructor: Robert D. Infelise Email: rinfelise@law.berkeley.edu Location: 115 Boalt, The Law of Hazardous Waste Disposal and Remediation (2d ed. 2005) Syllabus Class 1 ­ August 19 Claims

Kammen, Daniel M.

396

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.

397

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.

398

College of Law LLM in Oil and Gas Law  

E-print Network

College 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 it will be as successful as the other ones currently on offer. Anyone seeking to specialise in petroleum law should

Martin, Ralph R.

399

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

400

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.

401

International resources law  

SciTech Connect

This book covers: Historical origins of civil code legal systems; Modern civil law practice for mineral lawyers; Treaties and agreements for protection of international investments; Europe 1992-toward a single energy market; Dispute resolution in international agreements; Assessment of political risk; Reducing political risk; Protecting mineral investments from upheaval in developing countries; Typical world petroleum arrangements; government take in the Pacific Rim - Papua New Guinea; Mineral base of the USSR and prospects of investment; International taxation for the mining practitioner; Tax considerations - branch versus subsidiary; Doing business in the host country - nontax considerations; Impact of host-country laws on operations and profits; Mineral development and native rights - New Zealand; Designing the investment vehicle: mining; International oil and gas joint ventures; Selected U.S. laws with extraterritorial effect; U.S. tax and securities laws applied to foreign joint venturers; and Extraterritorial effect of U.S. laws.

Not Available

1991-01-01

402

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.

403

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

404

On Newton's Third Law  

E-print Network

The law of action-reaction is thoroughly used in textbooks to derive the conservation laws of linear and angular momentum, and it was considered by Ernst Mach the the cornerstone of physics. We give here a background survey of several questions raised by the action-reaction law, and in particular, the role of the physical vacuum is shown to provide an appropriate framework to clarify the occurrence of possible violations of the action-reaction law. It is also obtained an expression for the general linear momentum of a body-particle in the context of statistical mechanics. It is shown that Newton's third law is not verified in systems out of equilibrium due to an additional entropic gradient term present in the particle's momentum.

Pinheiro, Mario J

2009-01-01

405

Finite element analysis of damage accumulation for structure under impact  

NASA Astrophysics Data System (ADS)

Responses of structure under impact load are different from quasi-static process and fatigue. Especially when the impact load is cyclic loading and unloading, damage of structure is different form that of structure under single continuous load. Random impact load usually has high peak value, thus material in structure may contain plastic strain, and damage evolution is non-linear. For cyclic loading and unloading, elastic recovery process should be considered. These characteristics make it difficult to compute damage in FEA. In the paper, we use FEM and damage theories to compute cumulative damage of certain metal structure under cyclic loading and unloading, and statistic method is used in load setting. A series of experiments were carried out to verify the simulated results. It is proved that FEM can be used to acquire cumulative damage of structure under cyclic loading and unloading, and the results may be referenced in engineering design.

Hongyan, Wang; Guixiang, Hao

2011-07-01

406

Chemical Laws, Idealization and Approximation  

ERIC Educational Resources Information Center

This paper examines the notion of laws in chemistry. Vihalemm ("Found Chem" 5(1):7-22, 2003) argues that the laws of chemistry are fundamentally the same as the laws of physics they are all "ceteris paribus" laws which are true "in ideal conditions". In contrast, Scerri (2000) contends that the laws of chemistry are…

Tobin, Emma

2013-01-01

407

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

408

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

409

Philadelphia University Faculty of law  

E-print Network

/2008 Course Syllabus Course code: 410424Course Title: Maritime Law Course prerequisite (s) and/or corequisite: ( Prerequisite :Principles of Commercial Law) Module name: Maritime law Prerequisite: Introduction to commercial law Module number: 410424 Module number: 330270 This course is an introduction to maritime law insofar

410

Facing the damage together  

Microsoft Academic Search

This paper attempts to explore ideas about the nature of the attachment between a mother and her handicapped or damaged baby. I suggest that when a baby is found to be damaged, at or soon after birth, the parents' phantasy of a normal ‘beautiful’ baby dies and the mourning process is seldom adequately completed. Unbearable feelings of ‘primary disappointment’ (Emanuel,

Louise Emanuel

1997-01-01

411

Law and Economics as a Rhetorical Perspective in Law  

Microsoft Academic Search

Law and Economics as a Rhetorical Perspective in Law,\\u000aMichael D. Murray, Valparaiso University School of Law\\u000aAbstract\\u000aThis article introduces twenty-first century law and economics as a school of contemporary legal rhetoric—a rhetorical lens to test and improve general legal discourse in areas beyond the economic analysis of law. The recognition that the rhetoric of law and economics is

Michael D. Murray

2011-01-01

412

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.

413

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.

414

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

415

Love Canal: common law approaches to a modern tragedy  

Microsoft Academic Search

Love Canal is a classic example of the shortsighted approach industry has taken toward environmental damage and in the inequitable way in which social and economic costs are distributed. The elements of common law by which injured individuals take action against polluters like the Hooker Chemical Co. are examined. Several lines of defense - state of the art, assumption of

Baurer

2009-01-01

416

USACE Disaster Operations Public Law 84-99  

E-print Network

conditions (Engineering Regulation 500-1-1 provides specific details). All flood fight efforts require to prevent or reduce flood damage conditions of imminent threat of unusual flooding. · Rehabilitation: UnderUSACE Disaster Operations Public Law 84-99 - Flood Control and Coastal Emergency Act (PL 84

US Army Corps of Engineers

417

Anomalous law of cooling.  

PubMed

We analyze the temperature relaxation phenomena of systems in contact with a thermal reservoir that undergoes a non-Markovian diffusion process. From a generalized Langevin equation, we show that the temperature is governed by a law of cooling of the Newton's law type in which the relaxation time depends on the velocity autocorrelation and is then characterized by the memory function. The analysis of the temperature decay reveals the existence of an anomalous cooling in which the temperature may oscillate. Despite this anomalous behavior, we show that the variation of entropy remains always positive in accordance with the second law of thermodynamics. PMID:25770525

Lapas, Luciano C; Ferreira, Rogelma M S; Rubí, J Miguel; Oliveira, Fernando A

2015-03-14

418

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

419

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

420

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

421

PHILOSOPHY, POLITICS,PHILOSOPHY, POLITICS,PHILOSOPHY, POLITICS, & LAW& LAW& LAW  

E-print Network

PHILOSOPHY, POLITICS,PHILOSOPHY, POLITICS,PHILOSOPHY, POLITICS, & LAW& LAW& LAW theory, and elements of law. It may be of particular interest to students contemplating post-graduate work in law, those interested in a career in public service or politics, and those attracted

Krylov, Anna I.

422

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

423

New Integrable Nonlinear Evolution Equations  

Microsoft Academic Search

A new series of integrable nonlinear evolution equations is presented. The equations are novel in the sense that the nonlinear terms have saturation effects. It is shown that the equations have an infinite number of conservation laws and can be expressed in the Hamiltonian form.

Miki Wadati; Kimiaki Konno; Yoshi H. Ichikawa

1979-01-01

424

HIV-Specific Criminal Laws  

MedlinePLUS

... A-Z Topics Share Compartir HIV-Specific Criminal Laws During the early years of the HIV epidemic, ... number of states implemented HIV-specific criminal exposure laws. These laws impose criminal penalties on people living ...

425

Optical monitoring for power law fluids during spin coating.  

PubMed

Optical monitoring is applied, in situ and in real time, to non-newtonian, power law fluids in the spin coating process. An analytical exact solution is presented for thickness evolution that well fits to most measurement data. As result, typical rheological parameters are obtained for several CMC (carboximetilcelullose) concentrations and rotation speeds. Optical monitoring thus precisely indicates applicability of the model to power law fluids under spin coating. PMID:22330554

Jardim, P L G; Michels, A F; Horowitz, F

2012-01-30

426

Apparent damage accumulation in cancellous bone using neural networks.  

PubMed

In this paper, a neural network model is developed to simulate the accumulation of apparent fatigue damage of 3D trabecular bone architecture at a given bone site during cyclic loading. The method is based on five steps: (i) performing suitable numerical experiments to simulate fatigue accumulation of a 3D micro-CT trabecular bone samples taken from proximal femur for different combinations of loading conditions; (ii) averaging the sample outputs in terms of apparent damage at whole specimen level based on local tissue damage; (iii) preparation of a proper set of corresponding input-output data to train the network to identify apparent damage evolution; (iv) training the neural network based on the results of step (iii); (v) application of the neural network as a tool to estimate rapidly the apparent damage evolution at a given bone site. The proposed NN model can be incorporated into finite element codes to perform fatigue damage simulation at continuum level including some morphological factors and some bone material properties. The proposed neural network based multiscale approach is the first model, to the author's knowledge, that incorporates both finite element analysis and neural network computation to rapidly simulate multilevel fatigue of bone. This is beneficial to develop enhanced finite element models to investigate the role of damage accumulation on bone damage repair during remodelling. PMID:21616468

Hambli, Ridha

2011-08-01

427

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

428

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.

429

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."

430

Sobriety Checkpoint Laws  

MedlinePLUS

... Constitution (or interpretation of state law or Constitution). Texas prohibits them based on the its interpretation of ... a month Upheld under state and federal Constitution Texas No Illegal under Texas' interpretation of federal Constitution ...

431

What Are Newton's Laws?  

NSDL National Science Digital Library

Through a series of three lessons and one activity, students are introduced to inertia, forces and Newton's three laws of motion. For each lesson, a combination of class demonstrations and PowerPoint® presentations are used to explain, show and relate the concepts to engineering. Lesson 1 starts with inertia, forces and Newton's first law of motion. Lesson 2 builds on lesson 1 with s review and then introduces Newton's second law of motion. Lesson 3 builds on the previous two lessons with a review and then introduces Newton's third law of motion. In a culminating activity, students apply their knowledge of forces, friction, acceleration and gravity in an experiment to measure the average acceleration of a textbook pulled along a table by varying weights, and then test the effects of friction on different surfaces.

RESOURCE GK-12 Program, College of Engineering,

432

Ohm's Law I  

NSDL National Science Digital Library

Students work to increase the intensity of a light bulb by testing batteries in series and parallel circuits. They learn about Ohm's law, power, parallel and series circuits, and ways to measure voltage and current.

K-12 Outreach Office,

433

Assistive Technology Laws  

MedlinePLUS

Center on Technology and Disability Register Login Enter your keywords About CTD Events Home CTD Learning Center CTD Library CTD Cafe ... 12 » Inclusion » View Item AT Fact Sheet: Assistive Technology Laws Back to Search Results There is a ...

434

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.

435

Causal Newton Gravity Law  

E-print Network

The equations of the relativistic causal Newton gravity law for the planets of the solar system are studied in the approximation when the Sun rests at the coordinates origin and the planets do not iteract between each other.

Yury M. Zinoviev

2012-01-17

436

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

437

Symposium Issue "Law As . . ."  

E-print Network

543 The Peace: The Meaning and Production of Law in the Post-Revolutionary United States Laura F of War John Fabian Witt 895 Building an American Empire: Territorial Expansion in the Antebellum Era Paul

Barrett, Jeffrey A.

438

Teaching Criminal Law.  

ERIC Educational Resources Information Center

Presents learning activities and resources for teaching senior level criminal law courses. Topics covered include arrest, search and seizure, bail, trial procedures, sentencing, and prisons. Objective is to encourage students to address societal issues. (LS)

Levin, Sandy

1989-01-01

439

Assistive Technology Laws  

MedlinePLUS

... the Rehabilitation Act requires that all electronic and information technologies developed and used by any Federal government agency ... gov/telecom.html Federal Government Procurement of Accessible Information Technology Public Law 105-220 section 408 [29 USC ...

440

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

441

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

442

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 ...

443

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.

444

Non standard thermodynamics framework for robust computations with induced anisotropic damage  

E-print Network

-dissipation potential for the second one. The elasticity law and the strain energy release rate density YYY , variable of thermodynamics a pseudo-dissipation po- 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

445

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

446

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

447

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

448

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

449

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.

450

An elastic plastic damage formulation for concrete: application to elementary and structural tests  

Microsoft Academic Search

Pure elastic damage models or pure elastic plastic constitutive laws are not totally satisfactory to describe the behaviour of concrete. They indeed fail to reproduce the unloading slopes during cyclic loading which define experimentally the value of the damage in the material. When coupled effects are considered, in particular in hydro-mechanical problems, the capability of numerical models to reproduce the

Ludovic JASON; Antonio HUERTA; Gilles PIJAUDIER-CABOT

451

Damage in woven CFRP laminates subjected to low velocity impacts  

Microsoft Academic Search

Carbon fabric-reinforced polymer (CFRP) composites used in sports products can be exposed to different in-service conditions such as large dynamic bending deformations caused by impact loading. Composite materials subjected to such loads demonstrate various damage modes such as matrix cracking, delamination and, ultimately, fabric fracture. Damage evolution in these materials affects both their in-service properties and performance that can deteriorate

H Ullah; A A Abdel-Wahab; A R Harland; V V Silberschmidt

2012-01-01

452

Nonlocal conservation laws and related Bäcklund 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

453

Modeling of cumulative fatigue damage  

NASA Astrophysics Data System (ADS)

An investigation of cumulative fatigue damage under condition of block cyclic loading is presented. The general form of a damage function including the influence of loading history on cumulative damage is presented.

Golos, Krzysztof M.; Osinski, Zbigniew

454

The law of the leading digits and the world religions  

NASA Astrophysics Data System (ADS)

Benford's law states that the occurrence of significant digits in many data sets is not uniform but tends to follow a logarithmic distribution such that the smaller digits appear as first significant digits more frequently than the larger ones. We investigate here numerical data on the country-wise adherent distribution of seven major world religions i.e. Christianity, Islam, Buddhism, Hinduism, Sikhism, Judaism and Baha'ism to see if the proportion of the leading digits occurring in the distribution conforms to Benford's law. We find that the adherent data of all the religions, except Christianity, excellently does conform to Benford's law. Furthermore, unlike the adherent data on Christianity, the significant digit distribution of the three major Christian denominations i.e. Catholicism, Protestantism and Orthodoxy obeys the law. Thus in spite of their complexity general laws can be established for the evolution of religious groups.

Mir, T. A.

2012-02-01

455

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

456

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

457

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

458

94 University of Virginia School of Law Law School Foundation  

E-print Network

's College '63 Johns Hopkins University '64 Charles D. Fox IV, Law '80 Princeton University '75 Yale University '77 William B. Fryer, Law '74 University of Virginia '71 John W. Glynn, Jr., Law '65 University & Mary '67 William M. Slaughter, Law '66 Harvard University '61 Ex-Officio Members Paul G. Mahoney Yale

Acton, Scott

459

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.

460

APPLICATION FOR LAW 418: CLINICAL PRISON LAW INFORMATION AND INSTRUCTIONS  

E-print Network

APPLICATION FOR LAW 418: CLINICAL PRISON LAW INFORMATION AND INSTRUCTIONS LAW 418: CLINICAL PRISON advice, assistance and representation to prisoners in the seven penitentiaries in the Kingston area involved in the legal practice carried on by the Correctional Law Project. Students interview prisoner

Ellis, Randy

461

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

462

Composites Damage Tolerance Workshop  

NASA Technical Reports Server (NTRS)

The Composite Damage Tolerance Workshop included participants from NASA, academia, and private industry. The objectives of the workshop were to begin dialogue in order to establish a working group within the Agency, create awareness of damage tolerance requirements for Constellation, and discuss potential composite hardware for the Crew Launch Vehicle (CLV) Upper Stage (US) and Crew Module. It was proposed that a composites damage tolerance working group be created that acts within the framework of the existing NASA Fracture Control Methodology Panel. The working group charter would be to identify damage tolerance gaps and obstacles for implementation of composite structures into manned space flight systems and to develop strategies and recommendations to overcome these obstacles.

Gregg, Wayne

2006-01-01

463

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

464

Controlling Beaver Damage  

E-print Network

Damage Controlling BEAVER B eavers (Castor canadensis) are the largest rodents in North America. Their range includes most of North America, from the northern parts of Canada and Alaska to northern Mexico. Beavers are aquatic rodents which live...

Texas Wildlife Services

2007-03-13

465

Controlling Skunk Damage  

E-print Network

This publication discusses rabies, a diseases that skunks can transmit, and the damage that skunks can cause. Suggestions for environmental and mechanical control are given, as well as instructions on how to neutralize skunk odor....

Texas Wildlife Services

2007-03-13

466

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....

467

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.

468

Hysteretic nonlinearity analysis in damaged composite plates using guided waves.  

PubMed

Sensitivity of nonlinear acoustic methods to the presence and the evolution of micro-damage has been proven in various studies on a wide range of materials. In this contribution, a guided wave approach is proposed to characterize polymer based composite plates taken at intact as well as damaged states. The changes in the nonlinear hysteretic parameters are observed by changing the order of the excited flexural resonances. The analysis is based on the evolution of the velocity frequency dispersion of the generated guided waves, where flexural modes are considered separately and together as a function of the dynamic strain. PMID:23556688

Baccouche, Yousra; Bentahar, Mourad; Mechri, Charfeddine; El Guerjouma, Rachid; Hédi Ben Ghozlen, Mohamed

2013-04-01

469

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

470

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

471

Law and Economics as a Rhetorical Perspective in Law  

Microsoft Academic Search

Law and Economics as a Rhetorical Perspective in Law\\u000aMichael D. Murray\\u000aAbstract\\u000aThis article introduces twenty-first century law and economics as a school of contemporary legal rhetoric to test and improve general legal discourse in areas beyond the economic analysis of law. My article is the first to examine the prescriptive implications of the rhetoric of law and economics

Michael D. Murray

2011-01-01

472

Modeling process-induced cell damage in the biodispensing process.  

PubMed

Emerging biomanufacturing processes involve incorporation of living cells into various processes and systems by employing different cell manipulation techniques. Among them, biodispensing, in which the cell suspension is extruded via a fine needle under pressurized air, is a promising technique because of its high efficiency. Cells in this process are continually subjected to mechanical forces and may be damaged if the force or manipulation time exceeds certain levels. Modeling cell injury incurred in these processes is lacking in the literature. This article presents a method to quantify the force-induced cell damage in the biodispensing process. This method consists of two steps: first is to establish cell damage laws to relate cell damage to hydrostatic pressure/shear stress; and the second is to represent the process-induced forces experienced by cells during the biodispensing process and apply the established cell damage law to represent the percentage of cell damage. Schwann cells and 3T3 fibroblasts were used to validate the model and the comparisons of experimental and simulation results show the effectiveness of the method presented in this article. PMID:19715389

Li, Minggan; Tian, Xiaoyu; Zhu, Ning; Schreyer, David J; Chen, Xiongbiao

2010-06-01

473

Military Law Review  

NSDL National Science Digital Library

The Library of Congress' Research Center of Military Legal Resources contains, among other publications, the Military Law Review. The Military Law Review has been published quarterly since 1958, and is meant to be used by military attorneys in their work and "'provides a forum for those interested in military law to share the products of their experience and research.'" Visitors should also note that most of the issues from 1958 to 2008 are available for general perusal. Each issue of the journal contains both articles and book reviews. An article in the Winter 2008 issue, entitled "Crossing the Line: Reconciling the Right to Picket Military Funerals With the First Amendment", is a very accessible article about the constitutionality of state and federal funeral picketing laws. Visitors interested in learning about the school that provides military legal education, and where the Military Law Review is published, should click on the link "The Judge Advocate General's Legal Center & School (JAGS), U.S. Army, Charlottesville, Virginia", in the first paragraph on the homepage

474

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

475

Research Report faculty of law  

E-print Network

Research Report 2012 faculty of law #12;Contents Dean's message | 01 Associate Dean's message | 03 Resources Law | 12 Consumer Research Unit | 13 2011 Research publications | 15 #12;The UWA Law School has. Academics in the Law School continue to research and publish in a wide variety of legal areas as well

Tobar, Michael

476

EDUCATION LAW A Career Guide  

E-print Network

EDUCATION LAW A Career Guide Written By: Dan Ahearn, Attorney Advisor & Ross MacConnell, Summer Fellow 2009 Bernard Koteen Office of Public Interest Advising Harvard Law School Pound Hall, Room 329 Cambridge, MA 02138 (617) 495-3108 Fax: (617) 496-4944 pia@law.harvard.edu www.law

Wolfe, Patrick J.

477

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

478

COLLEGE OF LAW UNDERGRADUATE STUDIES  

E-print Network

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Martin, Ralph R.

479

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

480

[Cloning and law in Hungary].  

PubMed

Reproductive human cloning is prohibited in Hungary, as in many other countries. Therapeutic human cloning is not prohibited, just like in many other countries. Stem cell therapy is also allowed. Article III, paragraph (3) of the Hungarian basic law (constitution) strictly forbids total human cloning. Article 1 of the Additional Protocol to the Oviedo Convention, on the Prohibition of Cloning Human Beings (1998) stipulates that any intervention seeking to create a human being genetically identical to another human being, whether living or dead, is prohibited. In Hungary, according to Article 174 of the Criminal Code, total human cloning constitutes a crime. Article 180, paragraph (3) of the Hungarian Act on Health declares that embryos shall not be brought about for research purposes; research shall be conducted only on embryos brought about for reproductive purposes when this is authorized by the persons entitled to decide upon its disposal, or when the embryo is damaged. Article 180, paragraph (5) of the Hungarian Act on Health stipulates that multiple individuals who genetically conform to one another shall not be brought about. According to Article 181, paragraph (1) of the Hungarian Act on Health, an embryo used for research shall be kept alive for not longer than 14 days, not counting the time it was frozen for storage and the time period of research. Orv. Hetil., 2015, 156(11), 434-438. PMID:25749537

Julesz, Máté

2015-03-01

481

Microstructural evolution during dynamic deformation of cubic metals: copper  

SciTech Connect

Shockwave shape can influence dynamic damage evolution. Features such as rise time, pulse duration, peak shock pressure, pull back