Angular momentum conservation law in light-front quantum field theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu, Kelly Yu-Ju; Brodsky, Stanley J.

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3 , the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QEDmore » and QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.« less

Bäcklund transformation, infinitely-many conservation laws, solitary and periodic waves of an extended (3 + 1)-dimensional Jimbo-Miwa equation with time-dependent coefficients

NASA Astrophysics Data System (ADS)

Deng, Gao-Fu; Gao, Yi-Tian; Gao, Xin-Yi

2018-07-01

In this paper, an extended (3+1)-dimensional Jimbo-Miwa equation with time-dependent coefficients is investigated, which comes from the second member of the Kadomtsev-Petviashvili hierarchy and is shown to be conditionally integrable. Bilinear form, Bäcklund transformation, Lax pair and infinitely-many conservation laws are derived via the binary Bell polynomials and symbolic computation. With the help of the bilinear form, one-, two- and three-soliton solutions are obtained via the Hirota method, one-periodic wave solutions are constructed via the Riemann theta function. Additionally, propagation and interaction of the solitons are investigated analytically and graphically, from which we find that the interaction between the solitons is elastic and the time-dependent coefficients can affect the soliton velocities, but the soliton amplitudes remain unchanged. One-periodic waves approach the one-solitary waves with the amplitudes vanishing and can be viewed as a superposition of the overlapping solitary waves, placed one period apart.

Asymptotic Charges at Null Infinity in Any Dimension

NASA Astrophysics Data System (ADS)

Campoleoni, Andrea; Francia, Dario; Heissenberg, Carlo

2018-03-01

We analyse the conservation laws associated with large gauge transformations of massless fields in Minkowski space. Our aim is to highlight the interplay between boundary conditions and finiteness of the asymptotically conserved charges in any space-time dimension, both even and odd, greater than or equal to three. After discussing non-linear Yang-Mills theory and revisiting linearised gravity, our investigation extends to cover the infrared behaviour of bosonic massless quanta of any spin.

Lie symmetry analysis, conservation laws, solitary and periodic waves for a coupled Burger equation

NASA Astrophysics Data System (ADS)

Xu, Mei-Juan; Tian, Shou-Fu; Tu, Jian-Min; Zhang, Tian-Tian

2017-01-01

Under investigation in this paper is a generalized (2 + 1)-dimensional coupled Burger equation with variable coefficients, which describes lots of nonlinear physical phenomena in geophysical fluid dynamics, condense matter physics and lattice dynamics. By employing the Lie group method, the symmetry reductions and exact explicit solutions are obtained, respectively. Based on a direct method, the conservations laws of the equation are also derived. Furthermore, by virtue of the Painlevé analysis, we successfully obtain the integrable condition on the variable coefficients, which plays an important role in further studying the integrability of the equation. Finally, its auto-Bäcklund transformation as well as some new analytic solutions including solitary and periodic waves are also presented via algebraic and differential manipulation.

Infinite Conservation Laws, Continuous Symmetries and Invariant Solutions of Some Discrete Integrable Equations

NASA Astrophysics Data System (ADS)

Zhang, Yu-Feng; Zhang, Xiang-Zhi; Dong, Huan-He

2017-12-01

Two new shift operators are introduced for which a few differential-difference equations are generated by applying the R-matrix method. These equations can be reduced to the standard Toda lattice equation and (1+1)-dimensional and (2+1)-dimensional Toda-type equations which have important applications in hydrodynamics, plasma physics, and so on. Based on these consequences, we deduce the Hamiltonian structures of two discrete systems. Finally, we obtain some new infinite conservation laws of two discrete equations and employ Lie-point transformation group to obtain some continuous symmetries and part of invariant solutions for the (1+1) and (2+1)-dimensional Toda-type equations. Supported by the Fundamental Research Funds for the Central University under Grant No. 2017XKZD11

Extended symmetry analysis of generalized Burgers equations

NASA Astrophysics Data System (ADS)

Pocheketa, Oleksandr A.; Popovych, Roman O.

2017-10-01

Using enhanced classification techniques, we carry out the extended symmetry analysis of the class of generalized Burgers equations of the form ut + uux + f(t, x)uxx = 0. This enhances all the previous results on symmetries of these equations and includes the description of admissible transformations, Lie symmetries, Lie and nonclassical reductions, hidden symmetries, conservation laws, potential admissible transformations, and potential symmetries. The study is based on the fact that the class is normalized, and its equivalence group is finite-dimensional.

Multi-Hamiltonian structure of the Born-Infeld equation

NASA Astrophysics Data System (ADS)

Arik, Metin; Neyzi, Fahrünisa; Nutku, Yavuz; Olver, Peter J.; Verosky, John M.

1989-06-01

The multi-Hamiltonian structure, conservation laws, and higher order symmetries for the Born-Infeld equation are exhibited. A new transformation of the Born-Infeld equation to the equations of a Chaplygin gas is presented and explored. The Born-Infeld equation is distinguished among two-dimensional hyperbolic systems by its wealth of such multi-Hamiltonian structures.

Mass Conservation and Positivity Preservation with Ensemble-type Kalman Filter Algorithms

NASA Technical Reports Server (NTRS)

Janjic, Tijana; McLaughlin, Dennis B.; Cohn, Stephen E.; Verlaan, Martin

2013-01-01

Maintaining conservative physical laws numerically has long been recognized as being important in the development of numerical weather prediction (NWP) models. In the broader context of data assimilation, concerted efforts to maintain conservation laws numerically and to understand the significance of doing so have begun only recently. In order to enforce physically based conservation laws of total mass and positivity in the ensemble Kalman filter, we incorporate constraints to ensure that the filter ensemble members and the ensemble mean conserve mass and remain nonnegative through measurement updates. We show that the analysis steps of ensemble transform Kalman filter (ETKF) algorithm and ensemble Kalman filter algorithm (EnKF) can conserve the mass integral, but do not preserve positivity. Further, if localization is applied or if negative values are simply set to zero, then the total mass is not conserved either. In order to ensure mass conservation, a projection matrix that corrects for localization effects is constructed. In order to maintain both mass conservation and positivity preservation through the analysis step, we construct a data assimilation algorithms based on quadratic programming and ensemble Kalman filtering. Mass and positivity are both preserved by formulating the filter update as a set of quadratic programming problems that incorporate constraints. Some simple numerical experiments indicate that this approach can have a significant positive impact on the posterior ensemble distribution, giving results that are more physically plausible both for individual ensemble members and for the ensemble mean. The results show clear improvements in both analyses and forecasts, particularly in the presence of localized features. Behavior of the algorithm is also tested in presence of model error.

Chaos-assisted broadband momentum transformation in optical microresonators

NASA Astrophysics Data System (ADS)

Jiang, Xuefeng; Shao, Linbo; Zhang, Shu-Xin; Yi, Xu; Wiersig, Jan; Wang, Li; Gong, Qihuang; Lončar, Marko; Yang, Lan; Xiao, Yun-Feng

2017-10-01

The law of momentum conservation rules out many desired processes in optical microresonators. We report broadband momentum transformations of light in asymmetric whispering gallery microresonators. Assisted by chaotic motions, broadband light can travel between optical modes with different angular momenta within a few picoseconds. Efficient coupling from visible to near-infrared bands is demonstrated between a nanowaveguide and whispering gallery modes with quality factors exceeding 10 million. The broadband momentum transformation enhances the device conversion efficiency of the third-harmonic generation by greater than three orders of magnitude over the conventional evanescent-wave coupling. The observed broadband and fast momentum transformation could promote applications such as multicolor lasers, broadband memories, and multiwavelength optical networks.

Keeping the Promise of the 21st Century: Bringing Classroom Teaching into the Digital Age. Policy Brief

ERIC Educational Resources Information Center

Inverness Research, 2009

2009-01-01

The digital age has transformed how work is done in science, health care, the law, journalism, international relations, education, environmental conservation, agriculture, and engineering. To prepare students to thrive in today's society, teachers need to know more about how technologies are used in disciplines and workplaces, and--most…

2011 Mississippi Curriculum Framework: Postsecondary Conservation Law Enforcement Technology. (Program CIP: 03.0208 - Natural Resources Management and Policy, Other)

ERIC Educational Resources Information Center

Jones, Luke; Myrick, Dwight

2011-01-01

As the world economy continues to evolve, businesses and industries must adopt new practices and processes in order to survive. Quality and cost control, work teams and participatory management, and an infusion of technology are transforming the way people work and do business. Employees are now expected to read, write, and communicate…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mouchet, Amaury, E-mail: mouchet@phys.univ-tours.fr

The Noether theorem connecting symmetries and conservation laws can be applied directly in a Hamiltonian framework without using any intermediate Lagrangian formulation. This requires a careful discussion about the invariance of the boundary conditions under a canonical transformation and this paper proposes to address this issue. Then, the unified treatment of Hamiltonian systems offered by Noether’s approach is illustrated on several examples, including classical field theory and quantum dynamics.

Two-Phase Model of Combustion in Explosions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhl, A L; Khasainov, B; Bell, J

2006-06-19

A two-phase model for Aluminum particle combustion in explosions is proposed. It combines the gas-dynamic conservation laws for the gas phase with the continuum mechanics laws of multi-phase media, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by the Khasainov model. Combustion is specified as material transformations in the Le Chatelier diagram which depicts the locus of thermodynamic states in the internal energy-temperature plane according to Kuhl. Numerical simulations are used to show the evolution of two-phase combustion fields generated by the explosive dissemination of a powdered Al fuel.

Transforming narratives into educational tools: the collaborative development of a transformative learning tool based on Nicaraguan adolescents' creative writing about intimate partner violence.

PubMed

Singleton, Robyn; Picado Araúz, María de la Paz; Trocin, Kathleen; Winskell, Kate

2017-01-01

The use of narrative has become increasingly popular in the public health, community development, and education fields. Via emotionally engaging plotlines with authentic, captivating characters, stories provide an opportunity for participants to be carried away imaginatively into the characters' world while connecting the story with their own lived experiences. Stories have been highlighted as valuable tools in transformative learning. However, little published literature exists demonstrating applications of stories in group-based transformative learning curricula. This paper describes the creation of a narrative-based transformative learning tool based on an analysis of Nicaraguan adolescents' meaning-making around intimate partner violence (IPV) in their creative narratives. In collaboration with a Nicaraguan organization, US researchers analyzed a sample of narratives ( n = 55; 16 male-authored, 39 female-authored) on IPV submitted to a 2014 scriptwriting competition by adolescents aged 15-19. The data were particularly timely in that they responded to a new law protecting victims of gender-based violence, Law 779, and contradicted social-conservative claims that the Law 779 destroys family unity. We incorporated results from this analysis into the creation of the transformative learning tool, separated into thematic sections. The tool's sections (which comprise one story and three corresponding activities) aim to facilitate critical reflection, interpersonal dialogue, and self- and collective efficacy for social action around the following themes derived from the analysis: IPV and social support; IPV and romantic love; masculinity; warning signs of IPV; and sexual abuse. As a collaboration between a public health research team based at a US university and a Nicaraguan community-based organization, it demonstrates the potential in the age of increasingly smooth electronic communication for novel community-university partnerships to facilitate the development of narrative-based tools to support transformative learning.

Stability: Conservation laws, Painlevé analysis and exact solutions for S-KP equation in coupled dusty plasma

NASA Astrophysics Data System (ADS)

EL-Kalaawy, O. H.; Moawad, S. M.; Wael, Shrouk

The propagation of nonlinear waves in unmagnetized strongly coupled dusty plasma with Boltzmann distributed electrons, iso-nonthermal distributed ions and negatively charged dust grains is considered. The basic set of fluid equations is reduced to the Schamel Kadomtsev-Petviashvili (S-KP) equation by using the reductive perturbation method. The variational principle and conservation laws of S-KP equation are obtained. It is shown that the S-KP equation is non-integrable using Painlevé analysis. A set of new exact solutions are obtained by auto-Bäcklund transformations. The stability analysis is discussed for the existence of dust acoustic solitary waves (DASWs) and it is found that the physical parameters have strong effects on the stability criterion. In additional to, the electric field and the true Mach number of this solution are investigated. Finally, we will study the physical meanings of solutions.

Thermodynamic instability of topological black holes in Gauss-Bonnet gravity with a generalized electrodynamics

NASA Astrophysics Data System (ADS)

Hendi, S. H.; Panahiyan, S.

2014-12-01

Motivated by the string corrections on the gravity and electrodynamics sides, we consider a quadratic Maxwell invariant term as a correction of the Maxwell Lagrangian to obtain exact solutions of higher dimensional topological black holes in Gauss-Bonnet gravity. We first investigate the asymptotically flat solutions and obtain conserved and thermodynamic quantities which satisfy the first law of thermodynamics. We also analyze thermodynamic stability of the solutions by calculating the heat capacity and the Hessian matrix. Then, we focus on horizon-flat solutions with an anti-de Sitter (AdS) asymptote and produce a rotating spacetime with a suitable transformation. In addition, we calculate the conserved and thermodynamic quantities for asymptotically AdS black branes which satisfy the first law of thermodynamics. Finally, we perform thermodynamic instability criterion to investigate the effects of nonlinear electrodynamics in canonical and grand canonical ensembles.

f(R)-gravity from Killing tensors

NASA Astrophysics Data System (ADS)

Paliathanasis, Andronikos

2016-04-01

We consider f(R)-gravity in a Friedmann-Lemaître-Robertson-Walker spacetime with zero spatial curvature. We apply the Killing tensors of the minisuperspace in order to specify the functional form of f(R) and for the field equations to be invariant under Lie-Bäcklund transformations, which are linear in momentum (contact symmetries). Consequently, the field equations to admit quadratic conservation laws given by Noether’s theorem. We find three new integrable f(R)-models, for which, with the application of the conservation laws, we reduce the field equations to a system of two first-order ordinary differential equations. For each model we study the evolution of the cosmological fluid. We find that for each integrable model the cosmological fluid has an equation of state parameter, in which there is linear behavior in terms of the scale factor which describes the Chevallier, Polarski and Linder parametric dark energy model.

Chen Ning Yang, Weak Interactions, and Parity Violation

Science.gov Websites

absolute law of parity conservation had been violated." 2 "Yang overturned Paul ... Dirac's explained that symmetry laws generate the law of conservation. The law of right-left symmetry contributed to the formulation of the law of conservation of parity in 1924. Eventually, this law of conservation was

Conservation of Mass and Preservation of Positivity with Ensemble-Type Kalman Filter Algorithms

NASA Technical Reports Server (NTRS)

Janjic, Tijana; Mclaughlin, Dennis; Cohn, Stephen E.; Verlaan, Martin

2014-01-01

This paper considers the incorporation of constraints to enforce physically based conservation laws in the ensemble Kalman filter. In particular, constraints are used to ensure that the ensemble members and the ensemble mean conserve mass and remain nonnegative through measurement updates. In certain situations filtering algorithms such as the ensemble Kalman filter (EnKF) and ensemble transform Kalman filter (ETKF) yield updated ensembles that conserve mass but are negative, even though the actual states must be nonnegative. In such situations if negative values are set to zero, or a log transform is introduced, the total mass will not be conserved. In this study, mass and positivity are both preserved by formulating the filter update as a set of quadratic programming problems that incorporate non-negativity constraints. Simple numerical experiments indicate that this approach can have a significant positive impact on the posterior ensemble distribution, giving results that are more physically plausible both for individual ensemble members and for the ensemble mean. In two examples, an update that includes a non-negativity constraint is able to properly describe the transport of a sharp feature (e.g., a triangle or cone). A number of implementation questions still need to be addressed, particularly the need to develop a computationally efficient quadratic programming update for large ensemble.

A conservation law for virus infection kinetics in vitro.

PubMed

Kakizoe, Yusuke; Morita, Satoru; Nakaoka, Shinji; Takeuchi, Yasuhiro; Sato, Kei; Miura, Tomoyuki; Beauchemin, Catherine A A; Iwami, Shingo

2015-07-07

Conservation laws are among the most important properties of a physical system, but are not commonplace in biology. We derived a conservation law from the basic model for viral infections which consists in a small set of ordinary differential equations. We challenged the conservation law experimentally for the case of a virus infection in a cell culture. We found that the derived, conserved quantity remained almost constant throughout the infection period, implying that the derived conservation law holds in this biological system. We also suggest a potential use for the conservation law in evaluating the accuracy of experimental measurements. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chaos-assisted broadband momentum transformation in optical microresonators.

PubMed

Jiang, Xuefeng; Shao, Linbo; Zhang, Shu-Xin; Yi, Xu; Wiersig, Jan; Wang, Li; Gong, Qihuang; Lončar, Marko; Yang, Lan; Xiao, Yun-Feng

2017-10-20

The law of momentum conservation rules out many desired processes in optical microresonators. We report broadband momentum transformations of light in asymmetric whispering gallery microresonators. Assisted by chaotic motions, broadband light can travel between optical modes with different angular momenta within a few picoseconds. Efficient coupling from visible to near-infrared bands is demonstrated between a nanowaveguide and whispering gallery modes with quality factors exceeding 10 million. The broadband momentum transformation enhances the device conversion efficiency of the third-harmonic generation by greater than three orders of magnitude over the conventional evanescent-wave coupling. The observed broadband and fast momentum transformation could promote applications such as multicolor lasers, broadband memories, and multiwavelength optical networks. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Surface conservation laws at microscopically diffuse interfaces.

PubMed

Chu, Kevin T; Bazant, Martin Z

2007-11-01

In studies of interfaces with dynamic chemical composition, bulk and interfacial quantities are often coupled via surface conservation laws of excess surface quantities. While this approach is easily justified for microscopically sharp interfaces, its applicability in the context of microscopically diffuse interfaces is less theoretically well-established. Furthermore, surface conservation laws (and interfacial models in general) are often derived phenomenologically rather than systematically. In this article, we first provide a mathematically rigorous justification for surface conservation laws at diffuse interfaces based on an asymptotic analysis of transport processes in the boundary layer and derive general formulae for the surface and normal fluxes that appear in surface conservation laws. Next, we use nonequilibrium thermodynamics to formulate surface conservation laws in terms of chemical potentials and provide a method for systematically deriving the structure of the interfacial layer. Finally, we derive surface conservation laws for a few examples from diffusive and electrochemical transport.

Demonstrations of the Action and Reaction Law and the Energy Conservation Law Using Fine Spherical Plastic Beads

ERIC Educational Resources Information Center

Khumaeni, A.; Tanaka, S.; Kobayashi, A.; Lee, Y. I.; Kurniawan, K. H.; Ishii, K.; Kagawa, K.

2008-01-01

Equipment for demonstrating Newton's third law and the energy conservation law in mechanics have successfully been constructed utilizing fine spherical plastic beads in place of metal ball bearings. To demonstrate Newton's third law, special magnetized Petri dishes were employed as objects, while to examine the energy conservation law, a…

A Note on Weak Solutions of Conservation Laws and Energy/Entropy Conservation

NASA Astrophysics Data System (ADS)

Gwiazda, Piotr; Michálek, Martin; Świerczewska-Gwiazda, Agnieszka

2018-03-01

A common feature of systems of conservation laws of continuum physics is that they are endowed with natural companion laws which are in such cases most often related to the second law of thermodynamics. This observation easily generalizes to any symmetrizable system of conservation laws; they are endowed with nontrivial companion conservation laws, which are immediately satisfied by classical solutions. Not surprisingly, weak solutions may fail to satisfy companion laws, which are then often relaxed from equality to inequality and overtake the role of physical admissibility conditions for weak solutions. We want to answer the question: what is a critical regularity of weak solutions to a general system of conservation laws to satisfy an associated companion law as an equality? An archetypal example of such a result was derived for the incompressible Euler system in the context of Onsager's conjecture in the early nineties. This general result can serve as a simple criterion to numerous systems of mathematical physics to prescribe the regularity of solutions needed for an appropriate companion law to be satisfied.

Conservation laws and conserved quantities for (1+1)D linearized Boussinesq equations

NASA Astrophysics Data System (ADS)

Carvalho, Cindy; Harley, Charis

2017-05-01

Conservation laws and physical conserved quantities for the (1+1)D linearized Boussinesq equations at a constant water depth are presented. These equations describe incompressible, inviscid, irrotational fluid flow in the form of a non steady solitary wave. A systematic multiplier approach is used to obtain the conservation laws of the system of third order partial differential equations (PDEs) in dimensional form. Physical conserved quantities are derived by integrating the conservation laws in the direction of wave propagation and imposing decaying boundary conditions in the horizontal direction. One of these is a newly discovered conserved quantity which relates to an energy flux density.

From Outlaw to Citizen: Police Power, Property, and the Territorial Politics of Medical Marijuana in California’s Exurbs

PubMed Central

Polson, Michael

2018-01-01

As governments worldwide justify the transformation of marijuana governance from one police power (law enforcement) to others (e.g. public health, zoning), the place of marijuana in lawful society is transforming rapidly. No venue in California is more central to this than land use regulatory bodies, which decide how marijuana rights, practices, and relations become territorial. Land use powers, as a declaration of the state’s police power, require a definitional rendering of “community.” This article analyzes an episode of outdoor marijuana cultivation policymaking and the struggles over the definition of community in a conservative exurban California county. From debates on fences, property line setbacks, rental terms, and nuisance complaints to racial and economic anxieties and the roaming stigma of crime, marijuana advocates confronted a powerful logic of private property and the moral-aesthetic propriety it implies. Despite the subordination of advocates’ claims to the terms of private property, outlaw communities sustained their own forms of territorial governance, informal regulatory and enforcement powers, and understandings of community. This episode, which illuminates territorial production across illegal/legal lines, has implications for understandings of liberal rule of law, political possibility, and the practice of citizenship. PMID:29517073

Hyperbolic conservation laws and numerical methods

NASA Technical Reports Server (NTRS)

Leveque, Randall J.

1990-01-01

The mathematical structure of hyperbolic systems and the scalar equation case of conservation laws are discussed. Linear, nonlinear systems and the Riemann problem for the Euler equations are also studied. The numerical methods for conservation laws are presented in a nonstandard manner which leads to large time steps generalizations and computations on irregular grids. The solution of conservation laws with stiff source terms is examined.

78 FR 17229 - Notice of Lodging of Proposed Consent Decree Amendment Under the Clean Air Act; the Clean Water...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-20

... Act; the Clean Water Act; the Resource Conservation and Recovery Act; the Missouri Air Conservation Law; the Missouri Clean Water Law and the Missouri Hazardous Waste Management Law On March 14, 2013..., the Missouri Air Conservation Law, the Clean Water Act, the Missouri Clean Water Law, the Resource...

Frequency modulation at a moving material interface and a conservation law for wave number. [acoustic wave reflection and transmission

NASA Technical Reports Server (NTRS)

Kleinstein, G. G.; Gunzburger, M. D.

1976-01-01

An integral conservation law for wave numbers is considered. In order to test the validity of the proposed conservation law, a complete solution for the reflection and transmission of an acoustic wave impinging normally on a material interface moving at a constant speed is derived. The agreement between the frequency condition thus deduced from the dynamic equations of motion and the frequency condition derived from the jump condition associated with the integral equation supports the proposed law as a true conservation law. Additional comparisons such as amplitude discontinuities and Snells' law in a moving media further confirm the stated proposition. Results are stated concerning frequency and wave number relations across a shock front as predicted by the proposed conservation law.

On symmetries, conservation laws and exact solutions of the nonlinear Schrödinger-Hirota equation

NASA Astrophysics Data System (ADS)

Akbulut, Arzu; Taşcan, Filiz

2018-04-01

In this paper, conservation laws and exact solution are found for nonlinear Schrödinger-Hirota equation. Conservation theorem is used for finding conservation laws. We get modified conservation laws for given equation. Modified simple equation method is used to obtain the exact solutions of the nonlinear Schrödinger-Hirota equation. It is shown that the suggested method provides a powerful mathematical instrument for solving nonlinear equations in mathematical physics and engineering.

Nonlinear dynamics and control of a vibrating rectangular plate

NASA Technical Reports Server (NTRS)

Shebalin, J. V.

1983-01-01

The von Karman equations of nonlinear elasticity are solved for the case of a vibrating rectangular plate by meams of a Fourier spectral transform method. The amplification of a particular Fourier mode by nonlinear transfer of energy is demonstrated for this conservative system. The multi-mode system is reduced to a minimal (two mode) system, retaining the qualitative features of the multi-mode system. The effect of a modal control law on the dynamics of this minimal nonlinear elastic system is examined.

Geometry of Conservation Laws for a Class of Parabolic Partial Differential Equations

NASA Astrophysics Data System (ADS)

Clelland, Jeanne Nielsen

1996-08-01

I consider the problem of computing the space of conservation laws for a second-order, parabolic partial differential equation for one function of three independent variables. The PDE is formulated as an exterior differential system {cal I} on a 12 -manifold M, and its conservation laws are identified with the vector space of closed 3-forms in the infinite prolongation of {cal I} modulo the so -called "trivial" conservation laws. I use the tools of exterior differential systems and Cartan's method of equivalence to study the structure of the space of conservation laws. My main result is:. Theorem. Any conservation law for a second-order, parabolic PDE for one function of three independent variables can be represented by a closed 3-form in the differential ideal {cal I} on the original 12-manifold M. I show that if a nontrivial conservation law exists, then {cal I} has a deprolongation to an equivalent system {cal J} on a 7-manifold N, and any conservation law for {cal I} can be expressed as a closed 3-form on N which lies in {cal J}. Furthermore, any such system in the real analytic category is locally equivalent to a system generated by a (parabolic) equation of the formA(u _{xx}u_{yy}-u_sp {xy}{2}) + B_1u_{xx }+2B_2u_{xy} +B_3u_ {yy}+C=0crwhere A, B_{i}, C are functions of x, y, t, u, u_{x}, u _{y}, u_{t}. I compute the space of conservation laws for several examples, and I begin the process of analyzing the general case using Cartan's method of equivalence. I show that the non-linearizable equation u_{t} = {1over2}e ^{-u}(u_{xx}+u_ {yy})has an infinite-dimensional space of conservation laws. This stands in contrast to the two-variable case, for which Bryant and Griffiths showed that any equation whose space of conservation laws has dimension 4 or more is locally equivalent to a linear equation, i.e., is linearizable.

Quantum reference frames and their applications to thermodynamics.

PubMed

Popescu, Sandu; Sainz, Ana Belén; Short, Anthony J; Winter, Andreas

2018-07-13

We construct a quantum reference frame, which can be used to approximately implement arbitrary unitary transformations on a system in the presence of any number of extensive conserved quantities, by absorbing any back action provided by the conservation laws. Thus, the reference frame at the same time acts as a battery for the conserved quantities. Our construction features a physically intuitive, clear and implementation-friendly realization. Indeed, the reference system is composed of the same types of subsystems as the original system and is finite for any desired accuracy. In addition, the interaction with the reference frame can be broken down into two-body terms coupling the system to one of the reference frame subsystems at a time. We apply this construction to quantum thermodynamic set-ups with multiple, possibly non-commuting conserved quantities, which allows for the definition of explicit batteries in such cases.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'. © 2018 The Author(s).

On conservation laws for a generalized Boussinesq equation

NASA Astrophysics Data System (ADS)

Anco, S.; Rosa, M.; Gandarias, M. L.

2017-07-01

In this work, we study a Boussinesq equation with a strong damping term from the point of view of the Lie theory. By using the low order conservation laws we apply the conservation laws multiplier method to the associated potential systems.

Coherence Evolution and Transfer Supplemented by Sender's Initial-State Restoring

NASA Astrophysics Data System (ADS)

Fel'dman, E. B.; Zenchuk, A. I.

2017-12-01

The evolution of quantum coherences comes with a set of conservation laws provided that the Hamiltonian governing this evolution conserves the spin-excitation number. At that, coherences do not intertwist during the evolution. Using the transmission line and the receiver in the initial ground state we can transfer the coherences to the receiver without interaction between them, although the matrix elements contributing to each particular coherence intertwist in the receiver's state. Therefore we propose a tool based on the unitary transformation at the receiver side to untwist these elements and thus restore (at least partially) the structure of the sender's initial density matrix. A communication line with two-qubit sender and receiver is considered as an example of implementation of this technique.

7 CFR 1468.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... to the State or territorial soil conservation district law, or tribal law. The subdivision may be a conservation district, soil conservation district, soil and water conservation district, resource conservation... county or area, in accordance with Sec. 8(b) of the Soil Conservation and Domestic Allotment Act, as...

7 CFR 1468.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... to the State or territorial soil conservation district law, or tribal law. The subdivision may be a conservation district, soil conservation district, soil and water conservation district, resource conservation... county or area, in accordance with Sec. 8(b) of the Soil Conservation and Domestic Allotment Act, as...

7 CFR 1468.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... to the State or territorial soil conservation district law, or tribal law. The subdivision may be a conservation district, soil conservation district, soil and water conservation district, resource conservation... county or area, in accordance with Sec. 8(b) of the Soil Conservation and Domestic Allotment Act, as...

On the energy-momentum tensor in Moyal space

DOE PAGES

Balasin, Herbert; Blaschke, Daniel N.; Gieres, François; ...

2015-06-26

We study the properties of the energy-momentum tensor of gauge fields coupled to matter in non-commutative (Moyal) space. In general, the non-commutativity affects the usual conservation law of the tensor as well as its transformation properties (gauge covariance instead of gauge invariance). It is known that the conservation of the energy-momentum tensor can be achieved by a redefinition involving another starproduct. Furthermore, for a pure gauge theory it is always possible to define a gauge invariant energy-momentum tensor by means of a Wilson line. We show that the latter two procedures are incompatible with each other if couplings of gaugemore » fields to matter fields (scalars or fermions) are considered: The gauge invariant tensor (constructed via Wilson line) does not allow for a redefinition assuring its conservation, and vice-versa the introduction of another star-product does not allow for gauge invariance by means of a Wilson line.« less

A new numerical framework for solving conservation laws: The method of space-time conservation element and solution element

NASA Technical Reports Server (NTRS)

Chang, Sin-Chung; To, Wai-Ming

1991-01-01

A new numerical framework for solving conservation laws is being developed. It employs: (1) a nontraditional formulation of the conservation laws in which space and time are treated on the same footing, and (2) a nontraditional use of discrete variables such as numerical marching can be carried out by using a set of relations that represents both local and global flux conservation.

Integrable Semi-discrete Kundu-Eckhaus Equation: Darboux Transformation, Breather, Rogue Wave and Continuous Limit Theory

NASA Astrophysics Data System (ADS)

Zhao, Hai-qiong; Yuan, Jinyun; Zhu, Zuo-nong

2018-02-01

To get more insight into the relation between discrete model and continuous counterpart, a new integrable semi-discrete Kundu-Eckhaus equation is derived from the reduction in an extended Ablowitz-Ladik hierarchy. The integrability of the semi-discrete model is confirmed by showing the existence of Lax pair and infinite number of conservation laws. The dynamic characteristics of the breather and rational solutions have been analyzed in detail for our semi-discrete Kundu-Eckhaus equation to reveal some new interesting phenomena which was not found in continuous one. It is shown that the theory of the discrete system including Lax pair, Darboux transformation and explicit solutions systematically yields their continuous counterparts in the continuous limit.

On the conservation laws of Derrida-Lebowitz-Speer-Spohn equation

NASA Astrophysics Data System (ADS)

San, Sait; Yaşar, Emrullah

2015-05-01

In this study, the nonlocal conservation theorem and multiplier approach are performed on the 1 + 1 dimensional Derrida-Lebowitz-Speer-Spohn (DLSS) equation which arises in quantum semi conductor theory. We obtain local conservation laws by using the both methods. Furthermore by utilizing the relationship between conservation laws and Lie point symmetries, the DLSS equation is reduced to third order ordinary differential equation.

Exploiting the hidden symmetry of spinning black holes: conservation laws and numerical tests

NASA Astrophysics Data System (ADS)

Witzany, Vojtěch

2018-01-01

The Kerr black hole is stationary and axisymmetric, which leads to conservation of energy and azimuthal angular momentum along the orbits of free test particles in its vicinity, but also to conservation laws for the evolution of continuum matter fields. However, the Kerr space-time possesses an additional 'hidden symmetry', which exhibits itself in an unexpected conserved quantity along geodesics known as the Carter constant. We investigate the possibility of using this hidden symmetry to obtain conservation laws and other identities that could be used to test astrophysical simulations of the evolution of matter fields near spinning black holes. After deriving such identities, we set up a simple numerical toy model on which we demonstrate how they can detect the violations of evolution equations in a numerical simulation. Even though one of the expressions we derive is in the form of a conservation law, we end up recommending an equivalent but simpler expression that is not in the form of a conservation law for practical implementation.

Misunderstandings of "Law" and "Conservation": A Study of Pupils' Meanings of these Terms.

ERIC Educational Resources Information Center

Boyes, Edward; Stanisstreet, Martin

1990-01-01

Presented is the extent to which pupils of different ages tend to confuse scientific and everyday meanings of "Law" and "Conservation." The concepts of resource economy, environmental concern, and the law of conservation of energy are discussed in terms of potential teaching difficulties. (KR)

Energy Stable Flux Formulas For The Discontinuous Galerkin Discretization Of First Order Nonlinear Conservation Laws

NASA Technical Reports Server (NTRS)

Barth, Timothy; Charrier, Pierre; Mansour, Nagi N. (Technical Monitor)

2001-01-01

We consider the discontinuous Galerkin (DG) finite element discretization of first order systems of conservation laws derivable as moments of the kinetic Boltzmann equation. This includes well known conservation law systems such as the Euler For the class of first order nonlinear conservation laws equipped with an entropy extension, an energy analysis of the DG method for the Cauchy initial value problem is developed. Using this DG energy analysis, several new variants of existing numerical flux functions are derived and shown to be energy stable.

On a new semi-discrete integrable combination of Burgers and Sharma-Tasso-Olver equation

NASA Astrophysics Data System (ADS)

Zhao, Hai-qiong

2017-02-01

In this paper, a new semi-discrete integrable combination of Burgers and Sharma-Tasso-Olver equation is investigated. The underlying integrable structures like the Lax pair, the infinite number of conservation laws, the Darboux-Bäcklund transformation, and the solutions are presented in the explicit form. The theory of the semi-discrete equation including integrable properties yields the corresponding theory of the continuous counterpart in the continuous limit. Finally, numerical experiments are provided to demonstrate the effectiveness of the developed integrable semi-discretization algorithms.

Illustrating some implications of the conservation laws in relativistic mechanics

NASA Astrophysics Data System (ADS)

Boyer, Timothy H.

2009-06-01

The conservation laws of nonrelativistic and relativistic systems are reviewed and some simple illustrations are provided for the restrictive nature of the relativistic conservation law involving the center of energy compared to the nonrelativistic conservation law for the center of mass. Extension of the nonrelativistic interaction of particles through a potential to a system that is Lorentz-invariant through order v2/c2 is found to require new velocity- and acceleration-dependent forces that are suggestive of a field theory where the no-interaction theorem of Currie, Jordan, and Sudershan does not hold.

Dark optical, singular solitons and conservation laws to the nonlinear Schrödinger’s equation with spatio-temporal dispersion

NASA Astrophysics Data System (ADS)

Inc, Mustafa; Aliyu, Aliyu Isa; Yusuf, Abdullahi

2017-05-01

This paper studies the dynamics of solitons to the nonlinear Schrödinger’s equation (NLSE) with spatio-temporal dispersion (STD). The integration algorithm that is employed in this paper is the Riccati-Bernoulli sub-ODE method. This leads to dark and singular soliton solutions that are important in the field of optoelectronics and fiber optics. The soliton solutions appear with all necessary constraint conditions that are necessary for them to exist. There are four types of nonlinear media studied in this paper. They are Kerr law, power law, parabolic law and dual law. The conservation laws (Cls) for the Kerr law and parabolic law nonlinear media are constructed using the conservation theorem presented by Ibragimov.

Lagrangian and Hamiltonian constraints for guiding-center Hamiltonian theories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tronko, Natalia; Brizard, Alain J.

A consistent guiding-center Hamiltonian theory is derived by Lie-transform perturbation method, with terms up to second order in magnetic-field nonuniformity. Consistency is demonstrated by showing that the guiding-center transformation presented here satisfies separate Jacobian and Lagrangian constraints that have not been explored before. A new first-order term appearing in the guiding-center phase-space Lagrangian is identified through a calculation of the guiding-center polarization. It is shown that this new polarization term also yields a simpler expression of the guiding-center toroidal canonical momentum, which satisfies an exact conservation law in axisymmetric magnetic geometries. Finally, an application of the guiding-center Lagrangian constraint onmore » the guiding-center Hamiltonian yields a natural interpretation for its higher-order corrections.« less

Nonlocal Symmetries, Conservation Laws and Interaction Solutions of the Generalised Dispersive Modified Benjamin-Bona-Mahony Equation

NASA Astrophysics Data System (ADS)

Yan, Xue-Wei; Tian, Shou-Fu; Dong, Min-Jie; Wang, Xiu-Bin; Zhang, Tian-Tian

2018-05-01

We consider the generalised dispersive modified Benjamin-Bona-Mahony equation, which describes an approximation status for long surface wave existed in the non-linear dispersive media. By employing the truncated Painlevé expansion method, we derive its non-local symmetry and Bäcklund transformation. The non-local symmetry is localised by a new variable, which provides the corresponding non-local symmetry group and similarity reductions. Moreover, a direct method can be provided to construct a kind of finite symmetry transformation via the classic Lie point symmetry of the normal prolonged system. Finally, we find that the equation is a consistent Riccati expansion solvable system. With the help of the Jacobi elliptic function, we get its interaction solutions between solitary waves and cnoidal periodic waves.

76 FR 11396 - Energy Conservation Standards for Distribution Transformers: Public Meeting and Availability of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-02

... Conservation Standards for Distribution Transformers: Public Meeting and Availability of the Preliminary... the amendment of energy conservation standards for distribution transformers; the analytical framework..._standards/commercial/distribution_transformers.html . [[Page 11397

Novel Principles and the Charge-Symmetric Design of Dirac's Quantum Mechanics: I. Enhanced Eriksen's Theorem and the Universal Charge-Index Formalism for Dirac's Equation in (Strong) External Static Fields

NASA Astrophysics Data System (ADS)

Kononets, Yu. V.

2016-12-01

The presented enhanced version of Eriksen's theorem defines an universal transform of the Foldy-Wouthuysen type and in any external static electromagnetic field (ESEMF) reveals a discrete symmetry of Dirac's equation (DE), responsible for existence of a highly influential conserved quantum number—the charge index distinguishing two branches of DE spectrum. It launches the charge-index formalism (CIF) obeying the charge-index conservation law (CICL). Via its unique ability to manipulate each spectrum branch independently, the CIF creates a perfect charge-symmetric architecture of Dirac's quantum mechanics (DQM), which resolves all the riddles of the standard DE theory (SDET). Besides the abstract CIF algebra, the paper discusses: (1) the novel accurate charge-symmetric definition of the electric-current density; (2) DE in the true-particle representation, where electrons and positrons coexist on equal footing; (3) flawless "natural" scheme of second quantization; and (4) new physical grounds for the Fermi-Dirac statistics. As a fundamental quantum law, the CICL originates from the kinetic-energy sign conservation and leads to a novel single-particle physics in strong-field situations. Prohibiting Klein's tunneling (KT) in Klein's zone via the CICL, the precise CIF algebra defines a new class of weakly singular DE solutions, strictly confined in the coordinate space and experiencing the total reflection from the potential barrier.

Conserved Quantities in General Relativity: From the Quasi-Local Level to Spatial Infinity

NASA Astrophysics Data System (ADS)

Chen, Po-Ning; Wang, Mu-Tao; Yau, Shing-Tung

2015-08-01

We define quasi-local conserved quantities in general relativity by using the optimal isometric embedding in Wang and Yau (Commun Math Phys 288(3):919-942, 2009) to transplant Killing fields in the Minkowski spacetime back to the 2-surface of interest in a physical spacetime. To each optimal isometric embedding, a dual element of the Lie algebra of the Lorentz group is assigned. Quasi-local angular momentum and quasi-local center of mass correspond to pairing this element with rotation Killing fields and boost Killing fields, respectively. They obey classical transformation laws under the action of the Poincaré group. We further justify these definitions by considering their limits as the total angular momentum and the total center of mass of an isolated system. These expressions were derived from the Hamilton-Jacobi analysis of the gravitational action and thus satisfy conservation laws. As a result, we obtained an invariant total angular momentum theorem in the Kerr spacetime. For a vacuum asymptotically flat initial data set of order 1, it is shown that the limits are always finite without any extra assumptions. We also study these total conserved quantities on a family of asymptotically flat initial data sets evolving by the vacuum Einstein evolution equation. It is shown that the total angular momentum is conserved under the evolution. For the total center of mass, the classical dynamical formula relating the center of mass, energy, and linear momentum is recovered, in the nonlinear context of initial data sets evolving by the vacuum Einstein evolution equation. The definition of quasi-local angular momentum provides an answer to the second problem in classical general relativity on Penrose's list (Proc R Soc Lond Ser A 381(1780):53-63, 1982).

Geometry and symmetry in non-equilibrium thermodynamic systems

NASA Astrophysics Data System (ADS)

Sonnino, Giorgio

2017-06-01

The ultimate aim of this series of works is to establish the closure equations, valid for thermodynamic systems out from the Onsager region, and to describe the geometry and symmetry in thermodynamic systems far from equilibrium. Geometry of a non-equilibrium thermodynamic system is constructed by taking into account the second law of thermodynamics and by imposing the validity of the Glansdorff-Prigogine Universal Criterion of Evolution. These two constraints allow introducing the metrics and the affine connection of the Space of the Thermodynamic Forces, respectively. The Lie group associated to the nonlinear Thermodynamic Coordinate Transformations (TCT) leaving invariant both the entropy production σ and the Glansdorff-Prigogine dissipative quantity P, is also described. The invariance under TCT leads to the formulation of the Thermodynamic Covariance Principle (TCP): The nonlinear closure equations, i.e. the flux-force relations, must be covariant under TCT. In other terms, the fundamental laws of thermodynamics should be manifestly covariant under transformations between the admissible thermodynamic forces (i.e. under TCT). The symmetry properties of a physical system are intimately related to the conservation laws characterizing the thermodynamic system. Noether's theorem gives a precise description of this relation. The macroscopic theory for closure relations, based on this geometrical description and subject to the TCP, is referred to as the Thermodynamic Field Theory (TFT). This theory ensures the validity of the fundamental theorems for systems far from equilibrium.

The Conservation Principles and Kepler's Laws of Planetary Motion

ERIC Educational Resources Information Center

Motz, Lloyd

1975-01-01

Derives Kepler's three laws of planetary motion algebraically from conservation principles without introducing Newton's law of force explicitly. This procedure can be presented to students who have had no more than high school algebra. (Author)

Conservation laws for waves on a string from isometries and conformal isometries of the Minkowski metric

NASA Astrophysics Data System (ADS)

Miller, Brandon; Menon, Balraj

Noether's theorems describe the interplay between variational symmetries (symmetries of the action functional) and local conservation laws admitted by a physical system. In Lagrangian field theories defined on a differentiable manifold  endowed with a metric g, the variational symmetries are intimately tied to the isometries of the metric g. We highlight this connection by relating the variational symmetries of waves on a string to the isometries and conformal isometries of the Minkowski metric. The associated local conservation laws and conserved quantities for this physical system are determined and their physical significance discussed. The geometric nature of these conservation laws are further elucidated by discussing their Poisson bracket formulation in the Hamiltonian framework. This work was partially supported by the UCA Robert Noyce Scholars Program.

Conservation laws and rogue waves for a higher-order nonlinear Schrödinger equation with variable coefficients in the inhomogeneous fiber

NASA Astrophysics Data System (ADS)

Du, Zhong; Tian, Bo; Wu, Xiao-Yu; Liu, Lei; Sun, Yan

2017-07-01

Subpicosecond or femtosecond optical pulse propagation in the inhomogeneous fiber can be described by a higher-order nonlinear Schrödinger equation with variable coefficients, which is investigated in the paper. Via the Ablowitz-Kaup-Newell-Segur system and symbolic computation, the Lax pair and infinitely-many conservation laws are deduced. Based on the Lax pair and a modified Darboux transformation technique, the first- and second-order rogue wave solutions are constructed. Effects of the groupvelocity dispersion and third-order dispersion on the properties of the first- and second-order rouge waves are graphically presented and analyzed: The groupvelocity dispersion and third-order dispersion both affect the ranges and shapes of the first- and second-order rogue waves: The third-order dispersion can produce a skew angle of the first-order rogue wave and the skew angle rotates counterclockwise with the increase of the groupvelocity dispersion, when the groupvelocity dispersion and third-order dispersion are chosen as the constants; When the groupvelocity dispersion and third-order dispersion are taken as the functions of the propagation distance, the linear, X-shaped and parabolic trajectories of the rogue waves are obtained.

18 CFR 1314.4 - Law governing the rights and obligations of TVA and Reserve Banks; law governing the rights of...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Law governing the rights and obligations of TVA and Reserve Banks; law governing the rights of any Person against TVA and Reserve Banks; law governing other interests. 1314.4 Section 1314.4 Conservation of Power and Water...

Motion of gas in highly rarefied space

NASA Astrophysics Data System (ADS)

Chirkunov, Yu A.

2017-10-01

A model describing a motion of gas in a highly rarefied space received an unlucky number 13 in the list of the basic models of the motion of gas in the three-dimensional space obtained by L.V. Ovsyannikov. For a given initial pressure distribution, a special choice of mass Lagrangian variables leads to the system describing this motion for which the number of independent variables is less by one. Hence, there is a foliation of a highly rarefied gas with respect to pressure. In a strongly rarefied space for each given initial pressure distribution, all gas particles are localized on a two-dimensional surface that moves with time in this space We found some exact solutions of the obtained system that describe the processes taking place inside of the tornado. For this system we found all nontrivial conservation laws of the first order. In addition to the classical conservation laws the system has another conservation law, which generalizes the energy conservation law. With the additional condition we found another one generalized energy conservation law.

Hamiltonian structures for systems of hyperbolic conservation laws

NASA Astrophysics Data System (ADS)

Olver, Peter J.; Nutku, Yavuz

1988-07-01

The bi-Hamiltonian structure for a large class of one-dimensional hyberbolic systems of conservation laws in two field variables, including the equations of gas dynamics, shallow water waves, one-dimensional elastic media, and the Born-Infeld equation from nonlinear electrodynamics, is exhibited. For polytropic gas dynamics, these results lead to a quadri-Hamiltonian structure. New higher-order entropy-flux pairs (conservation laws) and higher-order symmetries are exhibited.

Development of a Hands-On Model Embedded with Guided Inquiry Laboratory to Enhance Students' Understanding of Law of Mechanical Energy Conservation

ERIC Educational Resources Information Center

Wangdi, Dumcho; Kanthang, Paisan; Precharattana, Monamorn

2017-01-01

This paper attempts to investigate the understanding of the law of mechanical energy conservation using a guided inquiry approach. A simple hands-on model was constructed and used to demonstrate the law of mechanical energy conservation. A total of 30 grade ten students from one of the middle secondary schools in western Bhutan participated in…

Analysis of self-similar solutions of multidimensional conservation laws

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keyfitz, Barbara Lee

2014-02-15

This project focused on analysis of multidimensional conservation laws, specifically on extensions to the study of self-siminar solutions, a project initiated by the PI. In addition, progress was made on an approach to studying conservation laws of very low regularity; in this research, the context was a novel problem in chromatography. Two graduate students in mathematics were supported during the grant period, and have almost completed their thesis research.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheviakov, Alexei F., E-mail: chevaikov@math.usask.ca

Partial differential equations of the form divN=0, N{sub t}+curl M=0 involving two vector functions in R{sup 3} depending on t, x, y, z appear in different physical contexts, including the vorticity formulation of fluid dynamics, magnetohydrodynamics (MHD) equations, and Maxwell's equations. It is shown that these equations possess an infinite family of local divergence-type conservation laws involving arbitrary functions of space and time. Moreover, it is demonstrated that the equations of interest have a rather special structure of a lower-degree (degree two) conservation law in R{sup 4}(t,x,y,z). The corresponding potential system has a clear physical meaning. For the Maxwell's equations,more » it gives rise to the scalar electric and the vector magnetic potentials; for the vorticity equations of fluid dynamics, the potentialization inverts the curl operator to yield the fluid dynamics equations in primitive variables; for MHD equations, the potential equations yield a generalization of the Galas-Bogoyavlenskij potential that describes magnetic surfaces of ideal MHD equilibria. The lower-degree conservation law is further shown to yield curl-type conservation laws and determined potential equations in certain lower-dimensional settings. Examples of new nonlocal conservation laws, including an infinite family of nonlocal material conservation laws of ideal time-dependent MHD equations in 2+1 dimensions, are presented.« less

A poroelastic medium saturated by a two-phase capillary fluid

NASA Astrophysics Data System (ADS)

Shelukhin, V. V.

2014-09-01

By Landau's approach developed for description of superfluidity of 2He, we derive a mathematical model for a poroelastic medium saturated with a two-phase capillary fluid. The model describes a three-velocity continuum with conservation laws which obey the basic principles of thermodynamics and which are consistent with the Galilean transformations. In contrast to Biot' linear theory, the equations derived allow for finite deformations. As the acoustic analysis reveals, there is one more longitudinal wave in comparison with the poroelastic medium saturated with a one-phase fluid. We prove that such a result is due to surface tension.

Statistical mechanical foundation of the peridynamic nonlocal continuum theory: energy and momentum conservation laws.

PubMed

Lehoucq, R B; Sears, Mark P

2011-09-01

The purpose of this paper is to derive the energy and momentum conservation laws of the peridynamic nonlocal continuum theory using the principles of classical statistical mechanics. The peridynamic laws allow the consideration of discontinuous motion, or deformation, by relying on integral operators. These operators sum forces and power expenditures separated by a finite distance and so represent nonlocal interaction. The integral operators replace the differential divergence operators conventionally used, thereby obviating special treatment at points of discontinuity. The derivation presented employs a general multibody interatomic potential, avoiding the standard assumption of a pairwise decomposition. The integral operators are also expressed in terms of a stress tensor and heat flux vector under the assumption that these fields are differentiable, demonstrating that the classical continuum energy and momentum conservation laws are consequences of the more general peridynamic laws. An important conclusion is that nonlocal interaction is intrinsic to continuum conservation laws when derived using the principles of statistical mechanics.

Statistical conservation law in two- and three-dimensional turbulent flows.

PubMed

Frishman, Anna; Boffetta, Guido; De Lillo, Filippo; Liberzon, Alex

2015-03-01

Particles in turbulence live complicated lives. It is nonetheless sometimes possible to find order in this complexity. It was proposed in Falkovich et al. [Phys. Rev. Lett. 110, 214502 (2013)] that pairs of Lagrangian tracers at small scales, in an incompressible isotropic turbulent flow, have a statistical conservation law. More specifically, in a d-dimensional flow the distance R(t) between two neutrally buoyant particles, raised to the power -d and averaged over velocity realizations, remains at all times equal to the initial, fixed, separation raised to the same power. In this work we present evidence from direct numerical simulations of two- and three-dimensional turbulence for this conservation. In both cases the conservation is lost when particles exit the linear flow regime. In two dimensions we show that, as an extension of the conservation law, an Evans-Cohen-Morriss or Gallavotti-Cohen type fluctuation relation exists. We also analyze data from a 3D laboratory experiment [Liberzon et al., Physica D 241, 208 (2012)], finding that although it probes small scales they are not in the smooth regime. Thus instead of 〈R-3〉, we look for a similar, power-law-in-separation conservation law. We show that the existence of an initially slowly varying function of this form can be predicted but that it does not turn into a conservation law. We suggest that the conservation of 〈R-d〉, demonstrated here, can be used as a check of isotropy, incompressibility, and flow dimensionality in numerical and laboratory experiments that focus on small scales.

Diffusion Processes Satisfying a Conservation Law Constraint

DOE PAGES

Bakosi, J.; Ristorcelli, J. R.

2014-03-04

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

Diffusion Processes Satisfying a Conservation Law Constraint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bakosi, J.; Ristorcelli, J. R.

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

Conservation law of angular momentum in helicity-dependent Raman and Rayleigh scattering

NASA Astrophysics Data System (ADS)

Tatsumi, Yuki; Kaneko, Tomoaki; Saito, Riichiro

2018-05-01

In first-order Raman scattering, helicity of circularly polarized incident light is either conserved or changed depending on the Raman modes. When the helicity of incident light changes in the scattered light, the angular momentum of a photon is transferred to the material. Here, we present the conservation law of pseudoangular momentum in the helicity-dependent Raman scattering for a N -fold (N =1 -4 ,6 ) rotational symmetry of a crystal. Furthermore, the conservation law of electron-phonon interaction is discussed by considering the vibration direction of a phonon that has the same or lower symmetry than the symmetry of the crystal, which is essential to allow the helicity change in Raman scattering in a highly symmetric material, such as graphene. We also discuss the conservation law of pseudoangular momentum in Rayleigh scattering and show that the helicity change is allowed only in the crystal with one- or twofold rotational symmetry.

Divergent conservation laws in hyperbolic thermoelasticity

NASA Astrophysics Data System (ADS)

Murashkin, E. V.; Radayev, Y. N.

2018-05-01

The present study is devoted to the problem of formulation of conservation laws in divergent form for hyperbolic thermoelastic continua. The field formalism is applied to study the problem. A natural density of thermoelastic action and the corresponding variational least action principle are formulated. A special form of the first variation of the action is employed to obtain 4-covariant divergent conservation laws. Differential field equations and constitutive laws are derived from a special form of the first variation of the action integral. The objectivity of constitutive equations is provided by the rotationally invariant forms of the Lagrangian employed.

78 FR 20291 - Fisheries of the United States; Billfish Conservation Act of 2012 Implementing Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

.... 121227743-3275-01] RIN 0648-BC86 Fisheries of the United States; Billfish Conservation Act of 2012... request public comment on potential issues related to the implementation of the Billfish Conservation Act... Conservation Act of 2012 (BCA), Public Law 112-183, 16 U.S.C. 1827a, was signed into law on October 5, 2012...

Conservation of wave action. [in discrete oscillating system

NASA Technical Reports Server (NTRS)

Hayes, W. D.

1974-01-01

It is pointed out that two basic principles appear in the theory of wave propagation, including the existence of a phase variable and a law governing the intensity, in terms of a conservation law. The concepts underlying such a conservation law are explored. The waves treated are conservative in the sense that they obey equations derivable from a variational principle applied to a Lagrangian functional. A discrete oscillating system is considered. The approach employed also permits in a natural way the definition of a local action density and flux in problems in which the waves are modal or general.

School, Government, and Energy Interactions.

ERIC Educational Resources Information Center

Canipe, Stephen L.

This document examines three major federal statutes affecting school energy conservation, describes laws and regulations enacted in North Carolina to promote school energy conservation, and touches on possible energy options open to schools. The federal laws discussed are the Energy Policy and Conservation Act of 1975, dealing with the…

Semi-discrete approximations to nonlinear systems of conservation laws; consistency and L(infinity)-stability imply convergence

NASA Technical Reports Server (NTRS)

Tadmor, Eitan

1988-01-01

A convergence theory for semi-discrete approximations to nonlinear systems of conservation laws is developed. It is shown, by a series of scalar counter-examples, that consistency with the conservation law alone does not guarantee convergence. Instead, a notion of consistency which takes into account both the conservation law and its augmenting entropy condition is introduced. In this context it is concluded that consistency and L(infinity)-stability guarantee for a relevant class of admissible entropy functions, that their entropy production rate belongs to a compact subset of H(loc)sup -1 (x,t). One can now use compensated compactness arguments in order to turn this conclusion into a convergence proof. The current state of the art for these arguments includes the scalar and a wide class of 2 x 2 systems of conservation laws. The general framework of the vanishing viscosity method is studied as an effective way to meet the consistency and L(infinity)-stability requirements. How this method is utilized to enforce consistency and stability for scalar conservation laws is shown. In this context we prove, under the appropriate assumptions, the convergence of finite difference approximations (e.g., the high resolution TVD and UNO methods), finite element approximations (e.g., the Streamline-Diffusion methods) and spectral and pseudospectral approximations (e.g., the Spectral Viscosity methods).

Semi-discrete approximations to nonlinear systems of conservation laws; consistency and L(infinity)-stability imply convergence. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tadmor, E.

1988-07-01

A convergence theory for semi-discrete approximations to nonlinear systems of conservation laws is developed. It is shown, by a series of scalar counter-examples, that consistency with the conservation law alone does not guarantee convergence. Instead, a notion of consistency which takes into account both the conservation law and its augmenting entropy condition is introduced. In this context it is concluded that consistency and L(infinity)-stability guarantee for a relevant class of admissible entropy functions, that their entropy production rate belongs to a compact subset of H(loc)sup -1 (x,t). One can now use compensated compactness arguments in order to turn this conclusionmore » into a convergence proof. The current state of the art for these arguments includes the scalar and a wide class of 2 x 2 systems of conservation laws. The general framework of the vanishing viscosity method is studied as an effective way to meet the consistency and L(infinity)-stability requirements. How this method is utilized to enforce consistency and stability for scalar conservation laws is shown. In this context we prove, under the appropriate assumptions, the convergence of finite difference approximations (e.g., the high resolution TVD and UNO methods), finite element approximations (e.g., the Streamline-Diffusion methods) and spectral and pseudospectral approximations (e.g., the Spectral Viscosity methods).« less

18 CFR 1314.4 - Law governing the rights and obligations of TVA and Reserve Banks; law governing the rights of...

Code of Federal Regulations, 2011 CFR

2011-04-01

... Reserve Banks; law governing other interests. 1314.4 Section 1314.4 Conservation of Power and Water... rights and obligations of TVA and Reserve Banks with respect to: (i) A Book-entry TVA Power Security or... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Law governing the...

The convergence of spectral methods for nonlinear conservation laws

NASA Technical Reports Server (NTRS)

Tadmor, Eitan

1987-01-01

The convergence of the Fourier method for scalar nonlinear conservation laws which exhibit spontaneous shock discontinuities is discussed. Numerical tests indicate that the convergence may (and in fact in some cases must) fail, with or without post-processing of the numerical solution. Instead, a new kind of spectrally accurate vanishing viscosity is introduced to augment the Fourier approximation of such nonlinear conservation laws. Using compensated compactness arguments, it is shown that this spectral viscosity prevents oscillations, and convergence to the unique entropy solution follows.

Identifying all moiety conservation laws in genome-scale metabolic networks.

PubMed

De Martino, Andrea; De Martino, Daniele; Mulet, Roberto; Pagnani, Andrea

2014-01-01

The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

Boundary Conditions for Infinite Conservation Laws

NASA Astrophysics Data System (ADS)

Rosenhaus, V.; Bruzón, M. S.; Gandarias, M. L.

2016-12-01

Regular soliton equations (KdV, sine-Gordon, NLS) are known to possess infinite sets of local conservation laws. Some other classes of nonlinear PDE possess infinite-dimensional symmetries parametrized by arbitrary functions of independent or dependent variables; among them are Zabolotskaya-Khokhlov, Kadomtsev-Petviashvili, Davey-Stewartson equations and Born-Infeld equation. Boundary conditions were shown to play an important role for the existence of local conservation laws associated with infinite-dimensional symmetries. In this paper, we analyze boundary conditions for the infinite conserved densities of regular soliton equations: KdV, potential KdV, Sine-Gordon equation, and nonlinear Schrödinger equation, and compare them with boundary conditions for the conserved densities obtained from infinite-dimensional symmetries with arbitrary functions of independent and dependent variables.

18 CFR 375.304 - Delegations to the Chief Administrative Law Judge.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Delegations to the Chief Administrative Law Judge. 375.304 Section 375.304 Conservation of Power and Water Resources... Law Judge to exercise the power granted to a Presiding Officer by part 385, particularly § 385.504 of...

18 CFR 375.304 - Delegations to the Chief Administrative Law Judge.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Delegations to the Chief Administrative Law Judge. 375.304 Section 375.304 Conservation of Power and Water Resources... Law Judge to exercise the power granted to a Presiding Officer by part 385, particularly § 385.504 of...

18 CFR 375.304 - Delegations to the Chief Administrative Law Judge.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Delegations to the Chief Administrative Law Judge. 375.304 Section 375.304 Conservation of Power and Water Resources... Law Judge to exercise the power granted to a Presiding Officer by part 385, particularly § 385.504 of...

18 CFR 375.304 - Delegations to the Chief Administrative Law Judge.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Delegations to the Chief Administrative Law Judge. 375.304 Section 375.304 Conservation of Power and Water Resources... Law Judge to exercise the power granted to a Presiding Officer by part 385, particularly § 385.504 of...

18 CFR 375.304 - Delegations to the Chief Administrative Law Judge.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Delegations to the Chief Administrative Law Judge. 375.304 Section 375.304 Conservation of Power and Water Resources... Law Judge to exercise the power granted to a Presiding Officer by part 385, particularly § 385.504 of...

Flux-vector splitting algorithm for chain-rule conservation-law form

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Nguyen, H. L.; Willis, E. A.; Steinthorsson, E.; Li, Z.

1991-01-01

A flux-vector splitting algorithm with Newton-Raphson iteration was developed for the 'full compressible' Navier-Stokes equations cast in chain-rule conservation-law form. The algorithm is intended for problems with deforming spatial domains and for problems whose governing equations cannot be cast in strong conservation-law form. The usefulness of the algorithm for such problems was demonstrated by applying it to analyze the unsteady, two- and three-dimensional flows inside one combustion chamber of a Wankel engine under nonfiring conditions. Solutions were obtained to examine the algorithm in terms of conservation error, robustness, and ability to handle complex flows on time-dependent grid systems.

Integrable aspects and rogue wave solution of Sasa-Satsuma equation with variable coefficients in the inhomogeneous fiber

NASA Astrophysics Data System (ADS)

Zhang, Yu-Ping; Yu, Lan; Wei, Guang-Mei

2018-02-01

Under investigation with symbolic computation in this paper, is a variable-coefficient Sasa-Satsuma equation (SSE) which can describe the ultra short pulses in optical fiber communications and propagation of deep ocean waves. By virtue of the extended Ablowitz-Kaup-Newell-Segur system, Lax pair for the model is directly constructed. Based on the obtained Lax pair, an auto-Bäcklund transformation is provided, then the explicit one-soliton solution is obtained. Meanwhile, an infinite number of conservation laws in explicit recursion forms are derived to indicate its integrability in the Liouville sense. Furthermore, exact explicit rogue wave (RW) solution is presented by use of a Darboux transformation. In addition to the double-peak structure and an analog of the Peregrine soliton, the RW can exhibit graphically an intriguing twisted rogue-wave (TRW) pair that involve four well-defined zero-amplitude points.

Composite scheme using localized relaxation with non-standard finite difference method for hyperbolic conservation laws

NASA Astrophysics Data System (ADS)

Kumar, Vivek; Raghurama Rao, S. V.

2008-04-01

Non-standard finite difference methods (NSFDM) introduced by Mickens [ Non-standard Finite Difference Models of Differential Equations, World Scientific, Singapore, 1994] are interesting alternatives to the traditional finite difference and finite volume methods. When applied to linear hyperbolic conservation laws, these methods reproduce exact solutions. In this paper, the NSFDM is first extended to hyperbolic systems of conservation laws, by a novel utilization of the decoupled equations using characteristic variables. In the second part of this paper, the NSFDM is studied for its efficacy in application to nonlinear scalar hyperbolic conservation laws. The original NSFDMs introduced by Mickens (1994) were not in conservation form, which is an important feature in capturing discontinuities at the right locations. Mickens [Construction and analysis of a non-standard finite difference scheme for the Burgers-Fisher equations, Journal of Sound and Vibration 257 (4) (2002) 791-797] recently introduced a NSFDM in conservative form. This method captures the shock waves exactly, without any numerical dissipation. In this paper, this algorithm is tested for the case of expansion waves with sonic points and is found to generate unphysical expansion shocks. As a remedy to this defect, we use the strategy of composite schemes [R. Liska, B. Wendroff, Composite schemes for conservation laws, SIAM Journal of Numerical Analysis 35 (6) (1998) 2250-2271] in which the accurate NSFDM is used as the basic scheme and localized relaxation NSFDM is used as the supporting scheme which acts like a filter. Relaxation schemes introduced by Jin and Xin [The relaxation schemes for systems of conservation laws in arbitrary space dimensions, Communications in Pure and Applied Mathematics 48 (1995) 235-276] are based on relaxation systems which replace the nonlinear hyperbolic conservation laws by a semi-linear system with a stiff relaxation term. The relaxation parameter ( λ) is chosen locally on the three point stencil of grid which makes the proposed method more efficient. This composite scheme overcomes the problem of unphysical expansion shocks and captures the shock waves with an accuracy better than the upwind relaxation scheme, as demonstrated by the test cases, together with comparisons with popular numerical methods like Roe scheme and ENO schemes.

Turing patterns in parabolic systems of conservation laws and numerically observed stability of periodic waves

NASA Astrophysics Data System (ADS)

Barker, Blake; Jung, Soyeun; Zumbrun, Kevin

2018-03-01

Turing patterns on unbounded domains have been widely studied in systems of reaction-diffusion equations. However, up to now, they have not been studied for systems of conservation laws. Here, we (i) derive conditions for Turing instability in conservation laws and (ii) use these conditions to find families of periodic solutions bifurcating from uniform states, numerically continuing these families into the large-amplitude regime. For the examples studied, numerical stability analysis suggests that stable periodic waves can emerge either from supercritical Turing bifurcations or, via secondary bifurcation as amplitude is increased, from subcritical Turing bifurcations. This answers in the affirmative a question of Oh-Zumbrun whether stable periodic solutions of conservation laws can occur. Determination of a full small-amplitude stability diagram - specifically, determination of rigorous Eckhaus-type stability conditions - remains an interesting open problem.

Flux vector splitting of the inviscid equations with application to finite difference methods

NASA Technical Reports Server (NTRS)

Steger, J. L.; Warming, R. F.

1979-01-01

The conservation-law form of the inviscid gasdynamic equations has the remarkable property that the nonlinear flux vectors are homogeneous functions of degree one. This property readily permits the splitting of flux vectors into subvectors by similarity transformations so that each subvector has associated with it a specified eigenvalue spectrum. As a consequence of flux vector splitting, new explicit and implicit dissipative finite-difference schemes are developed for first-order hyperbolic systems of equations. Appropriate one-sided spatial differences for each split flux vector are used throughout the computational field even if the flow is locally subsonic. The results of some preliminary numerical computations are included.

Biological conservation law as an emerging functionality in dynamical neuronal networks.

PubMed

Podobnik, Boris; Jusup, Marko; Tiganj, Zoran; Wang, Wen-Xu; Buldú, Javier M; Stanley, H Eugene

2017-11-07

Scientists strive to understand how functionalities, such as conservation laws, emerge in complex systems. Living complex systems in particular create high-ordered functionalities by pairing up low-ordered complementary processes, e.g., one process to build and the other to correct. We propose a network mechanism that demonstrates how collective statistical laws can emerge at a macro (i.e., whole-network) level even when they do not exist at a unit (i.e., network-node) level. Drawing inspiration from neuroscience, we model a highly stylized dynamical neuronal network in which neurons fire either randomly or in response to the firing of neighboring neurons. A synapse connecting two neighboring neurons strengthens when both of these neurons are excited and weakens otherwise. We demonstrate that during this interplay between the synaptic and neuronal dynamics, when the network is near a critical point, both recurrent spontaneous and stimulated phase transitions enable the phase-dependent processes to replace each other and spontaneously generate a statistical conservation law-the conservation of synaptic strength. This conservation law is an emerging functionality selected by evolution and is thus a form of biological self-organized criticality in which the key dynamical modes are collective.

Infinitesimal Bäcklund Transformation and Conservation Laws for Non-autonomous Systems

NASA Astrophysics Data System (ADS)

Mahato, G.; Chowdhury, A. Roy

We have observed that it is possible to extend the concept of the infinitesimal Bäcklund transformation of Steudel to the case of non-autonomous systems. We have discussed the situation with the cylindrical KdV as example. The interesting point to note is that though the B.T. for Ckdv does not possess the usual property of generating one soliton in a single operation, yet it generates an infinite number of symmetries, which corroborates with those obtained through the expansion of the resolvant of the linear operator associated with the equation.Translated AbstractInfinitesimale Bäcklund-Transformation und Erhaltungsgesetze nichtautonomer SystemeWir finden, daß es möglich ist, das Steudelsche Konzept der infinitesimalen Bäcklund-Transformation auf den Fall nichtautonomer Systeme zu übertragen. Als ein Beispiel wird die Situation bei einer zylindrischen KdV-Gleichung pehandelt. Der interessante Punkt ist dabei, daß die Bäcklund-Transformation - obwohl sie für die zylindrische KdV-Gleichung die übliche Eigenschaft, ein Soliton durch eine einzige Operation zu erzeugen, nicht besitzt - doch eine unendliche Zahl von Symmetrien erzeugt. Das bestätigt die Ergebnisse, die man durch Entwicklung der Resolvente des mit der Gleichung verknüpften linearen Operators erhält.

Travelling wave solutions and conservation laws for the Korteweg-de Vries-Bejamin-Bona-Mahony equation

NASA Astrophysics Data System (ADS)

Simbanefayi, Innocent; Khalique, Chaudry Masood

2018-03-01

In this work we study the Korteweg-de Vries-Benjamin-Bona-Mahony (KdV-BBM) equation, which describes the two-way propagation of waves. Using Lie symmetry method together with Jacobi elliptic function expansion and Kudryashov methods we construct its travelling wave solutions. Also, we derive conservation laws of the KdV-BBM equation using the variational derivative approach. In this method, we begin by computing second-order multipliers for the KdV-BBM equation followed by a derivation of the respective conservation laws for each multiplier.

Conservation laws and symmetries of a generalized Kawahara equation

NASA Astrophysics Data System (ADS)

Gandarias, Maria Luz; Rosa, Maria; Recio, Elena; Anco, Stephen

2017-06-01

The generalized Kawahara equation ut = a(t)uxxxxx + b(t)uxxx + c(t) f (u)ux appears in many physical applications. A complete classification of low-order conservation laws and point symmetries is obtained for this equation, which includes as a special case the usual Kawahara equation ut = αuux + βu2ux + γuxxx + μuxxxxx. A general connection between conservation laws and symmetries for the generalized Kawahara equation is derived through the Hamiltonian structure of this equation and its relationship to Noether's theorem using a potential formulation.

On the convergence of difference approximations to scalar conservation laws

NASA Technical Reports Server (NTRS)

Osher, Stanley; Tadmor, Eitan

1988-01-01

A unified treatment is given for time-explicit, two-level, second-order-resolution (SOR), total-variation-diminishing (TVD) approximations to scalar conservation laws. The schemes are assumed only to have conservation form and incremental form. A modified flux and a viscosity coefficient are introduced to obtain results in terms of the latter. The existence of a cell entropy inequality is discussed, and such an equality for all entropies is shown to imply that the scheme is an E scheme on monotone (actually more general) data, hence at most only first-order accurate in general. Convergence for TVD-SOR schemes approximating convex or concave conservation laws is shown by enforcing a single discrete entropy inequality.

Energetically consistent collisional gyrokinetics

DOE PAGES

Burby, J. W.; Brizard, A. J.; Qin, H.

2015-10-30

Here, we present a formulation of collisional gyrokinetic theory with exact conservation laws for energy and canonical toroidal momentum. Collisions are accounted for by a nonlinear gyrokinetic Landau operator. Gyroaveraging and linearization do not destroy the operator's conservation properties. Just as in ordinary kinetic theory, the conservation laws for collisional gyrokinetic theory are selected by the limiting collisionless gyrokinetic theory. (C) 2015 AIP Publishing LLC.

The Earth, the Moon and Conservation of Momentum

ERIC Educational Resources Information Center

Brunt, Marjorie; Brunt, Geoff

2013-01-01

We consider the application of both conservation of momentum and Newton's laws to the Moon in an assumed circular orbit about the Earth. The inadequacy of some texts in applying Newton's laws is considered.

On the convergence of difference approximations to scalar conservation laws

NASA Technical Reports Server (NTRS)

Osher, S.; Tadmor, E.

1985-01-01

A unified treatment of explicit in time, two level, second order resolution, total variation diminishing, approximations to scalar conservation laws are presented. The schemes are assumed only to have conservation form and incremental form. A modified flux and a viscosity coefficient are introduced and results in terms of the latter are obtained. The existence of a cell entropy inequality is discussed and such an equality for all entropies is shown to imply that the scheme is an E scheme on monotone (actually more general) data, hence at most only first order accurate in general. Convergence for total variation diminishing-second order resolution schemes approximating convex or concave conservation laws is shown by enforcing a single discrete entropy inequality.

Solutions and conservation laws for a Kaup-Boussinesq system

NASA Astrophysics Data System (ADS)

Motsepa, Tanki; Abudiab, Mufid; Khalique, Chaudry Masood

2017-07-01

In this work we study a Kaup-Boussinesq system, which is used in the analysis of long waves in shallow water. Travelling wave solutions are obtained by using direct integration. Secondly, conservation laws are derived by using the multiplier method.

The Impact of Transformational Leadership, Experiential Learning, and Reflective Journaling on the Conservation Ethic of Tertiary-Level Non-Science Majors

ERIC Educational Resources Information Center

Reynolds, Bradley Robert

2013-01-01

The impact of transformational leadership, experiential learning, and reflective journaling on the conservation ethic of non-science majors in a general education survey course was investigated. The main research questions were: (1) Is the Conservation of Biodiversity professor a transformational leader? (2) Is there a difference in the…

Simplified Relativistic Force Transformation Equation.

ERIC Educational Resources Information Center

Stewart, Benjamin U.

1979-01-01

A simplified relativistic force transformation equation is derived and then used to obtain the equation for the electromagnetic forces on a charged particle, calculate the electromagnetic fields due to a point charge with constant velocity, transform electromagnetic fields in general, derive the Biot-Savart law, and relate it to Coulomb's law.…

77 FR 32916 - Energy Conservation Standards for Distribution Transformers: Public Meeting and Availability of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-04

...-2010-BT-STD-0048] RIN 1904-AC04 Energy Conservation Standards for Distribution Transformers: Public... information that it is making available about the liquid-immersed distribution transformer equipment classes... equipment classes for several different types of liquid-immersed distribution transformers. In addition to...

10 CFR 431.196 - Energy conservation standards and their effective dates.

Code of Federal Regulations, 2014 CFR

2014-01-01

... CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Energy Conservation Standards § 431... Transformers. (1) The efficiency of a low-voltage, dry-type distribution transformer manufactured on or after... rating in the table below. Low-voltage dry-type distribution transformers with kVA ratings not appearing...

Higher-order jump conditions for conservation laws

NASA Astrophysics Data System (ADS)

Oksuzoglu, Hakan

2018-04-01

The hyperbolic conservation laws admit discontinuous solutions where the solution variables can have finite jumps in space and time. The jump conditions for conservation laws are expressed in terms of the speed of the discontinuity and the state variables on both sides. An example from the Gas Dynamics is the Rankine-Hugoniot conditions for the shock speed. Here, we provide an expression for the acceleration of the discontinuity in terms of the state variables and their spatial derivatives on both sides. We derive a jump condition for the shock acceleration. Using this general expression, we show how to obtain explicit shock acceleration formulas for nonlinear hyperbolic conservation laws. We start with the Burgers' equation and check the derived formula with an analytical solution. We next derive formulas for the Shallow Water Equations and the Euler Equations of Gas Dynamics. We will verify our formulas for the Euler Equations using an exact solution for the spherically symmetric blast wave problem. In addition, we discuss the potential use of these formulas for the implementation of shock fitting methods.

Progress on a Taylor weak statement finite element algorithm for high-speed aerodynamic flows

NASA Technical Reports Server (NTRS)

Baker, A. J.; Freels, J. D.

1989-01-01

A new finite element numerical Computational Fluid Dynamics (CFD) algorithm has matured to the point of efficiently solving two-dimensional high speed real-gas compressible flow problems in generalized coordinates on modern vector computer systems. The algorithm employs a Taylor Weak Statement classical Galerkin formulation, a variably implicit Newton iteration, and a tensor matrix product factorization of the linear algebra Jacobian under a generalized coordinate transformation. Allowing for a general two-dimensional conservation law system, the algorithm has been exercised on the Euler and laminar forms of the Navier-Stokes equations. Real-gas fluid properties are admitted, and numerical results verify solution accuracy, efficiency, and stability over a range of test problem parameters.

COMMENT Comment on 'Conservation laws of higher order nonlinear PDEs and the variational conservation laws in the class with mixed derivatives'

NASA Astrophysics Data System (ADS)

Sarlet, W.

2010-11-01

In a recent paper (R Narain and A H Kara 2010 J. Phys. A: Math. Theor. 43 085205), the authors claim to be applying Noether's theorem to higher-order partial differential equations and state that in a large class of examples 'the resultant conserved flows display some previously unknown interesting 'divergence properties' owing to the presence of the mixed derivatives' (citation from their abstract). It turns out that what this obscure sentence is meant to say is that the vector whose divergence must be zero (according to Noether's theorem), turns out to have non-zero divergence and subsequently must be modified to obtain a true conservation law. Clearly this cannot be right: we explain in detail the main source of the error.

Vorticity and symplecticity in multi-symplectic, Lagrangian gas dynamics

NASA Astrophysics Data System (ADS)

Webb, G. M.; Anco, S. C.

2016-02-01

The Lagrangian, multi-dimensional, ideal, compressible gas dynamic equations are written in a multi-symplectic form, in which the Lagrangian fluid labels, m i (the Lagrangian mass coordinates) and time t are the independent variables, and in which the Eulerian position of the fluid element {x}={x}({m},t) and the entropy S=S({m},t) are the dependent variables. Constraints in the variational principle are incorporated by means of Lagrange multipliers. The constraints are: the entropy advection equation S t = 0, the Lagrangian map equation {{x}}t={u} where {u} is the fluid velocity, and the mass continuity equation which has the form J=τ where J={det}({x}{ij}) is the Jacobian of the Lagrangian map in which {x}{ij}=\\partial {x}i/\\partial {m}j and τ =1/ρ is the specific volume of the gas. The internal energy per unit volume of the gas \\varepsilon =\\varepsilon (ρ ,S) corresponds to a non-barotropic gas. The Lagrangian is used to define multi-momenta, and to develop de Donder-Weyl Hamiltonian equations. The de Donder-Weyl equations are cast in a multi-symplectic form. The pullback conservation laws and the symplecticity conservation laws are obtained. One class of symplecticity conservation laws give rise to vorticity and potential vorticity type conservation laws, and another class of symplecticity laws are related to derivatives of the Lagrangian energy conservation law with respect to the Lagrangian mass coordinates m i . We show that the vorticity-symplecticity laws can be derived by a Lie dragging method, and also by using Noether’s second theorem and a fluid relabelling symmetry which is a divergence symmetry of the action. We obtain the Cartan-Poincaré form describing the equations and we discuss a set of differential forms representing the equation system.

Sound radiated by the interaction of non-homogeneous turbulence on a transversely sheared flow with leading and trailing edges of semi-infinite flat plate

NASA Astrophysics Data System (ADS)

Afsar, Mohammed; Sassanis, Vasilis

2017-11-01

The small amplitude unsteady motion on a transversely sheared mean flow is determined by two arbitrary convected quantities with a particular choice of gauge in which the Fourier transform of the pressure is linearly-related to a scalar potential whose integral solution can be written in terms of one of these convected quantities. This formulation becomes very useful for studying Rapid-distortion theory problems involving solid surface interaction. Recent work by Goldstein et al. (JFM, 2017) has shown that the convected quantities are related to the turbulence by exact conservation laws, which allow the upstream boundary conditions for interaction of a turbulent shear flow with a solid-surface (for example) to be derived self-consistently with appropriate asymptotic separation of scales. This result requires the imposition of causality on an intermediate variable within the conservation laws that represents the local particle displacement. In this talk, we use the model derived in Goldstein et al. for trailing edge noise and compare it to leading edge noise on a semi-infinite flat plate positioned parallel to the level curves of the mean flow. Since the latter represents the leading order solution for the aerofoil interaction problem, these results are expected to be generic. M.Z.A. would also like to thank Strathclyde University for financial support from the Chancellor's Fellowship.

Gauge and integrable theories in loop spaces

NASA Astrophysics Data System (ADS)

Ferreira, L. A.; Luchini, G.

2012-05-01

We propose an integral formulation of the equations of motion of a large class of field theories which leads in a quite natural and direct way to the construction of conservation laws. The approach is based on generalized non-abelian Stokes theorems for p-form connections, and its appropriate mathematical language is that of loop spaces. The equations of motion are written as the equality of a hyper-volume ordered integral to a hyper-surface ordered integral on the border of that hyper-volume. The approach applies to integrable field theories in (1+1) dimensions, Chern-Simons theories in (2+1) dimensions, and non-abelian gauge theories in (2+1) and (3+1) dimensions. The results presented in this paper are relevant for the understanding of global properties of those theories. As a special byproduct we solve a long standing problem in (3+1)-dimensional Yang-Mills theory, namely the construction of conserved charges, valid for any solution, which are invariant under arbitrary gauge transformations.

Fechner's law: where does the log transform come from?

PubMed

Laming, Donald

2010-01-01

This paper looks at Fechner's law in the light of 150 years of subsequent study. In combination with the normal, equal variance, signal-detection model, Fechner's law provides a numerically accurate account of discriminations between two separate stimuli, essentially because the logarithmic transform delivers a model for Weber's law. But it cannot be taken to be a measure of internal sensation because an equally accurate account is provided by a chi(2) model in which stimuli are scaled by their physical magnitude. The logarithmic transform of Fechner's law arises because, for the number of degrees of freedom typically required in the chi(2) model, the logarithm of a chi(2) variable is, to a good approximation, normal. This argument is set within a general theory of sensory discrimination.

Second-order accurate nonoscillatory schemes for scalar conservation laws

NASA Technical Reports Server (NTRS)

Huynh, Hung T.

1989-01-01

Explicit finite difference schemes for the computation of weak solutions of nonlinear scalar conservation laws is presented and analyzed. These schemes are uniformly second-order accurate and nonoscillatory in the sense that the number of extrema of the discrete solution is not increasing in time.

45 CFR 673.1 - Purpose of regulations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ANTARCTIC NON... implement the Antarctic Conservation Act of 1978, Public Law 95-541, as amended by the Antarctic Science, Tourism and Conservation Act of 1996, Public Law 104-227, and Article 15 of the Protocol on Environmental...

45 CFR 673.1 - Purpose of regulations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ANTARCTIC NON... implement the Antarctic Conservation Act of 1978, Public Law 95-541, as amended by the Antarctic Science, Tourism and Conservation Act of 1996, Public Law 104-227, and Article 15 of the Protocol on Environmental...

45 CFR 673.1 - Purpose of regulations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ANTARCTIC NON... implement the Antarctic Conservation Act of 1978, Public Law 95-541, as amended by the Antarctic Science, Tourism and Conservation Act of 1996, Public Law 104-227, and Article 15 of the Protocol on Environmental...

45 CFR 673.1 - Purpose of regulations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION ANTARCTIC NON... implement the Antarctic Conservation Act of 1978, Public Law 95-541, as amended by the Antarctic Science, Tourism and Conservation Act of 1996, Public Law 104-227, and Article 15 of the Protocol on Environmental...

[Forestry Law and the conservation of natural areas and wildlife].

PubMed

Villacrés, V; Suárez, M; Tafur, V

1996-04-01

The Forest Law of Ecuador consists of 107 articles, whereas its regulations contain 269 articles. They are related to forestry resources, forestry patrimony protection, forests and vegetation, forest production and benefits, the control and mobilization of the forestry resources, research and capacitation, and the forestry industry protection; to natural areas, wild flora and fauna, their patrimony, conservation, and economic support; and to the violation of the law and its judgment.

Biological conservation law as an emerging functionality in dynamical neuronal networks

PubMed Central

Podobnik, Boris; Tiganj, Zoran; Wang, Wen-Xu; Buldú, Javier M.

2017-01-01

Scientists strive to understand how functionalities, such as conservation laws, emerge in complex systems. Living complex systems in particular create high-ordered functionalities by pairing up low-ordered complementary processes, e.g., one process to build and the other to correct. We propose a network mechanism that demonstrates how collective statistical laws can emerge at a macro (i.e., whole-network) level even when they do not exist at a unit (i.e., network-node) level. Drawing inspiration from neuroscience, we model a highly stylized dynamical neuronal network in which neurons fire either randomly or in response to the firing of neighboring neurons. A synapse connecting two neighboring neurons strengthens when both of these neurons are excited and weakens otherwise. We demonstrate that during this interplay between the synaptic and neuronal dynamics, when the network is near a critical point, both recurrent spontaneous and stimulated phase transitions enable the phase-dependent processes to replace each other and spontaneously generate a statistical conservation law—the conservation of synaptic strength. This conservation law is an emerging functionality selected by evolution and is thus a form of biological self-organized criticality in which the key dynamical modes are collective. PMID:29078286

A new flux-conserving numerical scheme for the steady, incompressible Navier-Stokes equations

NASA Technical Reports Server (NTRS)

Scott, James R.

1994-01-01

This paper is concerned with the continued development of a new numerical method, the space-time solution element (STS) method, for solving conservation laws. The present work focuses on the two-dimensional, steady, incompressible Navier-Stokes equations. Using first an integral approach, and then a differential approach, the discrete flux conservation equations presented in a recent paper are rederived. Here a simpler method for determining the flux expressions at cell interfaces is given; a systematic and rigorous derivation of the conditions used to simulate the differential form of the governing conservation law(s) is provided; necessary and sufficient conditions for a discrete approximation to satisfy a conservation law in E2 are derived; and an estimate of the local truncation error is given. A specific scheme is then constructed for the solution of the thin airfoil boundary layer problem. Numerical results are presented which demonstrate the ability of the scheme to accurately resolve the developing boundary layer and wake regions using grids which are much coarser than those employed by other numerical methods. It is shown that ten cells in the cross-stream direction are sufficient to accurately resolve the developing airfoil boundary layer.

Limitations on the Evolution of Quantum Coherences: Towards Fully Quantum Second Laws of Thermodynamics.

PubMed

Ćwikliński, Piotr; Studziński, Michał; Horodecki, Michał; Oppenheim, Jonathan

2015-11-20

The second law of thermodynamics places a limitation into which states a system can evolve into. For systems in contact with a heat bath, it can be combined with the law of energy conservation, and it says that a system can only evolve into another if the free energy goes down. Recently, it's been shown that there are actually many second laws, and that it is only for large macroscopic systems that they all become equivalent to the ordinary one. These additional second laws also hold for quantum systems, and are, in fact, often more relevant in this regime. They place a restriction on how the probabilities of energy levels can evolve. Here, we consider additional restrictions on how the coherences between energy levels can evolve. Coherences can only go down, and we provide a set of restrictions which limit the extent to which they can be maintained. We find that coherences over energy levels must decay at rates that are suitably adapted to the transition rates between energy levels. We show that the limitations are matched in the case of a single qubit, in which case we obtain the full characterization of state-to-state transformations. For higher dimensions, we conjecture that more severe constraints exist. We also introduce a new class of thermodynamical operations which allow for greater manipulation of coherences and study its power with respect to a class of operations known as thermal operations.

Illustrating dynamical symmetries in classical mechanics: The Laplace-Runge-Lenz vector revisited

NASA Astrophysics Data System (ADS)

O'Connell, Ross C.; Jagannathan, Kannan

2003-03-01

The inverse square force law admits a conserved vector that lies in the plane of motion. This vector has been associated with the names of Laplace, Runge, and Lenz, among others. Many workers have explored aspects of the symmetry and degeneracy associated with this vector and with analogous dynamical symmetries. We define a conserved dynamical variable α that characterizes the orientation of the orbit in two-dimensional configuration space for the Kepler problem and an analogous variable β for the isotropic harmonic oscillator. This orbit orientation variable is canonically conjugate to the angular momentum component normal to the plane of motion. We explore the canonical one-parameter group of transformations generated by α(β). Because we have an obvious pair of conserved canonically conjugate variables, it is desirable to use them as a coordinate-momentum pair. In terms of these phase space coordinates, the form of the Hamiltonian is nearly trivial because neither member of the pair can occur explicitly in the Hamiltonian. From these considerations we gain a simple picture of dynamics in phase space. The procedure we use is in the spirit of the Hamilton-Jacobi method.

2×2 systems of conservation laws with L data

NASA Astrophysics Data System (ADS)

Bianchini, Stefano; Colombo, Rinaldo M.; Monti, Francesca

Consider a hyperbolic system of conservation laws with genuinely nonlinear characteristic fields. We extend the classical Glimm-Lax (1970) result [13, Theorem 5.1] proving the existence of solutions for L initial datum, relaxing the assumptions taken therein on the geometry of the shock-rarefaction curves.

Simplified Discontinuous Galerkin Methods for Systems of Conservation Laws with Convex Extension

NASA Technical Reports Server (NTRS)

Barth, Timothy J.

1999-01-01

Simplified forms of the space-time discontinuous Galerkin (DG) and discontinuous Galerkin least-squares (DGLS) finite element method are developed and analyzed. The new formulations exploit simplifying properties of entropy endowed conservation law systems while retaining the favorable energy properties associated with symmetric variable formulations.

Insect sex determination: it all evolves around transformer.

PubMed

Verhulst, Eveline C; van de Zande, Louis; Beukeboom, Leo W

2010-08-01

Insects exhibit a variety of sex determining mechanisms including male or female heterogamety and haplodiploidy. The primary signal that starts sex determination is processed by a cascade of genes ending with the conserved switch doublesex that controls sexual differentiation. Transformer is the doublesex splicing regulator and has been found in all examined insects, indicating its ancestral function as a sex-determining gene. Despite this conserved function, the variation in transformer nucleotide sequence, amino acid composition and protein structure can accommodate a multitude of upstream sex determining signals. Transformer regulation of doublesex and its taxonomic distribution indicate that the doublesex-transformer axis is conserved among all insects and that transformer is the key gene around which variation in sex determining mechanisms has evolved.

Carnot cycle for interacting particles in the absence of thermal noise.

PubMed

Curado, Evaldo M F; Souza, Andre M C; Nobre, Fernando D; Andrade, Roberto F S

2014-02-01

A thermodynamic formalism is developed for a system of interacting particles under overdamped motion, which has been recently analyzed within the framework of nonextensive statistical mechanics. It amounts to expressing the interaction energy of the system in terms of a temperature θ, conjugated to a generalized entropy s(q), with q = 2. Since θ assumes much higher values than those of typical room temperatures T ≪ θ, the thermal noise can be neglected for this system (T/θ ≃ 0). This framework is now extended by the introduction of a work term δW which, together with the formerly defined heat contribution (δ Q = θ ds(q)), allows for the statement of a proper energy conservation law that is analogous to the first law of thermodynamics. These definitions lead to the derivation of an equation of state and to the characterization of s(q) adiabatic and θ isothermic transformations. On this basis, a Carnot cycle is constructed, whose efficiency is shown to be η = 1-(θ(2)/θ(1)), where θ(1) and θ(2) are the effective temperatures of the two isothermic transformations, with θ(1)>θ(2). The results for a generalized thermodynamic description of this system open the possibility for further physical consequences, like the realization of a thermal engine based on energy exchanges gauged by the temperature θ.

Integrability from point symmetries in a family of cosmological Horndeski Lagrangians

NASA Astrophysics Data System (ADS)

Dimakis, N.; Giacomini, Alex; Paliathanasis, Andronikos

2017-07-01

For a family of Horndeski theories, formulated in terms of a generalized Galileon model, we study the integrability of the field equations in a Friedmann-Lemaître-Robertson-Walker space-time. We are interested in point transformations which leave invariant the field equations. Noether's theorem is applied to determine the conservation laws for a family of models that belong to the same general class. The cosmological scenarios with or without an extra perfect fluid with constant equation of state parameter are the two important cases of our study. The de Sitter universe and ideal gas solutions are derived by using the invariant functions of the symmetry generators as a demonstration of our result. Furthermore, we discuss the connection of the different models under conformal transformations while we show that when the Horndeski theory reduces to a canonical field the same holds for the conformal equivalent theory. Finally, we discuss how singular solutions provides nonsingular universes in a different frame and vice versa.

A family of wave equations with some remarkable properties.

PubMed

da Silva, Priscila Leal; Freire, Igor Leite; Sampaio, Júlio Cesar Santos

2018-02-01

We consider a family of homogeneous nonlinear dispersive equations with two arbitrary parameters. Conservation laws are established from the point symmetries and imply that the whole family admits square integrable solutions. Recursion operators are found for two members of the family investigated. For one of them, a Lax pair is also obtained, proving its complete integrability. From the Lax pair, we construct a Miura-type transformation relating the original equation to the Korteweg-de Vries (KdV) equation. This transformation, on the other hand, enables us to obtain solutions of the equation from the kernel of a Schrödinger operator with potential parametrized by the solutions of the KdV equation. In particular, this allows us to exhibit a kink solution to the completely integrable equation from the 1-soliton solution of the KdV equation. Finally, peakon-type solutions are also found for a certain choice of the parameters, although for this particular case the equation is reduced to a homogeneous second-order nonlinear evolution equation.

A True Proteus: A history of energy conservation in German science and culture, 1847-1914

NASA Astrophysics Data System (ADS)

Wegener, F. D. A.

2009-11-01

This thesis follows the career of the law of energy conservation in German science and culture between 1847 and 1914. There is an interesting contrast between the initial reception of Hermann Helmholtz’ 1847 treatise ‘Über die Erhaltung der Kraft’, which was rejected by the editor of the Annalen der Physik, and its later status as a classic of science. ‘Energy’ was the shared concept of the disciplines. It was used by physiologists, physicists, psychologists, sociologists and philosophers. Moreover, the law of energy conservation also made a huge cultural impact. The period around 1900 has justly been called an energetic era. Why did the law of energy conservation become such a universal success? The obvious way to explain this success would be to say: because it is true, and subsequently comment upon its great scientific value. This thesis adopts a different perspective. It adopts Wittgenstein’s definition of meaning as use in language. Consequently, the meaning of the law is only referred to in relation to the way in which it was put to use in communicative practice. From this perspective it is immediately evident that the understanding of the law of energy conservation was subject to considerable change. Helmholtz initially conceptualized the law in terms of atoms and forces; Gustav Kirchhoff and Ernst Mach, rejected atoms and forces as hypothetical entities and they preferred to use the more mundane concept of work instead; Wilhelm Ostwald, finally, thought of energy as an immaterial substance. This thesis meticulously follows the changes in use and understanding to which the law was subject as it penetrated German science and culture. Communication and interests, rather than natural essences, are the central explanatory concepts of the thesis. From 1847 onwards Helmholtz and Du Bois-Reymond actively sought to spread the law of energy conservation among their colleagues and the general public. They told their fellow physiologists, for example, that the law could be invoked as an argument against vitalism. In popular scientific lectures they emphasized the law’s connection to Germany’s industrialization and its ethical value. Thus they partly shaped the reception of the law. But of course, its reception could not be completely controlled. People have interests of their own and they often appropriated the law in unexpected ways. This thesis’ stress on meaning as use, and its use of concepts like interests and appropriation may make it appear as if energy was whatever people wanted it to be. This is a misunderstanding. Obviously, within a specific community, there were limits to what one could reasonably make of energy. But these were social as much as intellectual constraints. More importantly, by the turn of the century, the law of energy conservation had acquired a certain ubiquity in German science and culture. The continuous talk about energy had a persuasive power of its own. Centerum censeo, Du Bois-Reymond said. Ultimately, the law imposed itself on everybody, even those who tried to ignore it.

The emergence of place-based conservation [Chapter 1

Treesearch

Daniel R. Williams; William P. Stewart; Linda E. Kruger

2013-01-01

Place has emerged as a significant topic within conservation research and practice. The transformative changes connected to contemporary conservation are related to recognition of multi-scaled, social-ecological dynamics; emergent, multiscaled governance structures; and rising importance of place-specific meanings and local knowledge. These transformative changes are...

A kinetic equation with kinetic entropy functions for scalar conservation laws

NASA Technical Reports Server (NTRS)

Perthame, Benoit; Tadmor, Eitan

1990-01-01

A nonlinear kinetic equation is constructed and proved to be well-adapted to describe general multidimensional scalar conservation laws. In particular, it is proved to be well-posed uniformly in epsilon - the microscopic scale. It is also shown that the proposed kinetic equation is equipped with a family of kinetic entropy functions - analogous to Boltzmann's microscopic H-function, such that they recover Krushkov-type entropy inequality on the macroscopic scale. Finally, it is proved by both - BV compactness arguments in the one-dimensional case, that the local density of kinetic particles admits a continuum limit, as it converges strongly with epsilon below 0 to the unique entropy solution of the corresponding conservation law.

Science communication and vernal pool conservation: a study of local decision maker attitudes in a knowledge-action system.

PubMed

McGreavy, Bridie; Webler, Thomas; Calhoun, Aram J K

2012-03-01

In this study, we describe local decision maker attitudes towards vernal pools to inform science communication and enhance vernal pool conservation efforts. We conducted interviews with town planning board and conservation commission members (n = 9) from two towns in the State of Maine in the northeastern United States. We then mailed a questionnaire to a stratified random sample of planning board members in August and September 2007 with a response rate of 48.4% (n = 320). The majority of survey respondents favored the protection and conservation of vernal pools in their towns. Decision makers were familiar with the term "vernal pool" and demonstrated positive attitudes to vernal pools in general. General appreciation and willingness to conserve vernal pools predicted support for the 2006 revisions to the Natural Resource Protection Act regulating Significant Vernal Pools. However, 48% of respondents were unaware of this law and neither prior knowledge of the law nor workshop attendance predicted support for the vernal pool law. Further, concerns about private property rights and development restrictions predicted disagreement with the vernal pool law. We conclude that science communication must rely on specific frames of reference, be sensitive to cultural values, and occur in an iterative system to link knowledge and action in support of vernal pool conservation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Conservation laws of wave action and potential enstrophy for Rossby waves in a stratified atmosphere

NASA Technical Reports Server (NTRS)

Straus, D. M.

1983-01-01

The evolution of wave energy, enstrophy, and wave motion for atmospheric Rossby waves in a variable mean flow are discussed from a theoretical and pedagogic standpoint. In the absence of mean flow gradients, the wave energy density satisfies a local conservation law, with the appropriate flow velocity being the group velocity. In the presence of mean flow variations, wave energy is not conserved, but wave action is, provided the mean flow is independent of longitude. Wave enstrophy is conserved for arbitrary variations of the mean flow. Connections with Eiiassen-Palm flux are also discussed.

Discontinuous Spectral Difference Method for Conservation Laws on Unstructured Grids

NASA Technical Reports Server (NTRS)

Liu, Yen; Vinokur, Marcel; Wang, Z. J.

2004-01-01

A new, high-order, conservative, and efficient method for conservation laws on unstructured grids is developed. The concept of discontinuous and high-order local representations to achieve conservation and high accuracy is utilized in a manner similar to the Discontinuous Galerkin (DG) and the Spectral Volume (SV) methods, but while these methods are based on the integrated forms of the equations, the new method is based on the differential form to attain a simpler formulation and higher efficiency. A discussion on the Discontinuous Spectral Difference (SD) Method, locations of the unknowns and flux points and numerical results are also presented.

Conservation laws of wave action and potential enstrophy for Rossby waves in a stratified atmosphere

NASA Technical Reports Server (NTRS)

Straus, D. M.

1983-01-01

The evolution of wave energy, enstrophy, and wave motion for atmospheric Rossby waves in a variable mean flow are discussed from a theoretical and pedagogic standpoint. In the absence of mean flow gradients, the wave energy density satisfies a local conservation law, with the appropriate flow velocity being the group velocity. In the presence of mean flow variations, wave energy is not conserved, but wave action is, provided the mean flow is independent of longitude. Wave enstrophy is conserved for arbitrary variations of the mean flow. Connections with Eliassen-Palm flux are also discussed.

Conservation form of the equations of fluid dynamics in general nonsteady coordinates

NASA Astrophysics Data System (ADS)

Zhang, H.; Camarero, R.; Kahawita, R.

1985-11-01

Many of the differential equations arising in fluid dynamics may be stated in conservation-law form. A number of investigations have been conducted with the aim to derive the conservation-law form of the Navier-Stokes equations in general nonsteady coordinate systems. The present note has the objective to illustrate a mathematical methodology with which such forms of the equations may be derived in an easier and more general fashion. For numerical applications, the scalar form of the equations is eventually provided. Attention is given to the conservation form of equations in curvilinear coordinates and numerical considerations.

76 FR 70749 - Information Collection Request Sent to the Office of Management and Budget (OMB) for Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... the ICR online at http://www.reginfo.gov . Follow the instructions to review Department of the... programs associated with the North American Wetlands Conservation Act (NAWCA), Public Law 101-233, and the Neotropical Migratory Bird Conservation Act (NMBCA), Public Law 106-247. Currently, information that we...

An Historical Note on the Conservation of Mass

ERIC Educational Resources Information Center

Whitaker, Robert D.

1975-01-01

Discusses the fact that although most historians of science attribute the formulation of the law of conservation of matter in chemical reactions to Antoine Lavoisier at the end of the eighteenth century, several earlier researchers had already assumed this law in their work. These researchers include Joseph Black, Henry Cavendish, M. V. Lomonosov,…

Conservation laws in the quantum Hall Liouvillian theory and its generalizations

NASA Astrophysics Data System (ADS)

Moore, Joel

2003-03-01

It is known that the localization length scaling of noninteracting electrons near the quantum Hall plateau transition can be described in a theory of the bosonic density operators, with no reference to the underlying fermions. The resulting ``Liouvillian'' theory has a U(1|1) global supersymmetry as well as a hierarchy of geometric conservation laws related to the noncommutative geometry of the lowest Landau level (LLL). Mean-field and large-N generalizations of the Liouvillian are shown to describe problems of noninteracting bosons (without any obvious pathologies, contrary to recent claims) that enlarge the U(1|1) supersymmetry to U(1|1) × SO(N) or U(1|1) × SU(N). The N>1 generalizations preserve the first two of the hierarchy of geometric conservation laws, leading to logarithmic corrections at order 1/N to the diffusive large-N limit, but do not preserve the remaining conservation laws. The emergence of nontrivial scaling at the plateau transition, in the Liouvillian approach, is shown to depend sensitively on the unusual geometry of Landau levels.

A high-order relaxation method with projective integration for solving nonlinear systems of hyperbolic conservation laws

NASA Astrophysics Data System (ADS)

Lafitte, Pauline; Melis, Ward; Samaey, Giovanni

2017-07-01

We present a general, high-order, fully explicit relaxation scheme which can be applied to any system of nonlinear hyperbolic conservation laws in multiple dimensions. The scheme consists of two steps. In a first (relaxation) step, the nonlinear hyperbolic conservation law is approximated by a kinetic equation with stiff BGK source term. Then, this kinetic equation is integrated in time using a projective integration method. After taking a few small (inner) steps with a simple, explicit method (such as direct forward Euler) to damp out the stiff components of the solution, the time derivative is estimated and used in an (outer) Runge-Kutta method of arbitrary order. We show that, with an appropriate choice of inner step size, the time step restriction on the outer time step is similar to the CFL condition for the hyperbolic conservation law. Moreover, the number of inner time steps is also independent of the stiffness of the BGK source term. We discuss stability and consistency, and illustrate with numerical results (linear advection, Burgers' equation and the shallow water and Euler equations) in one and two spatial dimensions.

Noether symmetries and stability of ideal gas solutions in Galileon cosmology

NASA Astrophysics Data System (ADS)

Dimakis, N.; Giacomini, Alex; Jamal, Sameerah; Leon, Genly; Paliathanasis, Andronikos

2017-03-01

A class of generalized Galileon cosmological models, which can be described by a pointlike Lagrangian, is considered in order to utilize Noether's theorem to determine conservation laws for the field equations. In the Friedmann-Lemaître-Robertson-Walker universe, the existence of a nontrivial conservation law indicates the integrability of the field equations. Because of the complexity of the latter, we apply the differential invariants approach in order to construct special power-law solutions and study their stability.

Conservation laws with coinciding smooth solutions but different conserved variables

NASA Astrophysics Data System (ADS)

Colombo, Rinaldo M.; Guerra, Graziano

2018-04-01

Consider two hyperbolic systems of conservation laws in one space dimension with the same eigenvalues and (right) eigenvectors. We prove that solutions to Cauchy problems with the same initial data differ at third order in the total variation of the initial datum. As a first application, relying on the classical Glimm-Lax result (Glimm and Lax in Decay of solutions of systems of nonlinear hyperbolic conservation laws. Memoirs of the American Mathematical Society, No. 101. American Mathematical Society, Providence, 1970), we obtain estimates improving those in Saint-Raymond (Arch Ration Mech Anal 155(3):171-199, 2000) on the distance between solutions to the isentropic and non-isentropic inviscid compressible Euler equations, under general equations of state. Further applications are to the general scalar case, where rather precise estimates are obtained, to an approximation by Di Perna of the p-system and to a traffic model.

Discretization and Preconditioning Algorithms for the Euler and Navier-Stokes Equations on Unstructured Meshes

NASA Technical Reports Server (NTRS)

Bart, Timothy J.; Kutler, Paul (Technical Monitor)

1998-01-01

Chapter 1 briefly reviews several related topics associated with the symmetrization of systems of conservation laws and quasi-conservation laws: (1) Basic Entropy Symmetrization Theory; (2) Symmetrization and eigenvector scaling; (3) Symmetrization of the compressible Navier-Stokes equations; and (4) Symmetrization of the quasi-conservative form of the magnetohydrodynamic (MHD) equations. Chapter 2 describes one of the best known tools employed in the study of differential equations, the maximum principle: any function f(x) which satisfies the inequality f(double prime)>0 on the interval [a,b] attains its maximum value at one of the endpoints on the interval. Chapter three examines the upwind finite volume schemes for scalar and system conservation laws. The basic tasks in the upwind finite volume approach have already been presented: reconstruction, flux evaluation, and evolution. By far, the most difficult task in this process is the reconstruction step.

Second- and third-order upwind difference schemes for hyperbolic conservation laws

NASA Technical Reports Server (NTRS)

Yang, J. Y.

1984-01-01

Second- and third-order two time-level five-point explicit upwind-difference schemes are described for the numerical solution of hyperbolic systems of conservation laws and applied to the Euler equations of inviscid gas dynamics. Nonliner smoothing techniques are used to make the schemes total variation diminishing. In the method both hyperbolicity and conservation properties of the hyperbolic conservation laws are combined in a very natural way by introducing a normalized Jacobian matrix of the hyperbolic system. Entropy satisfying shock transition operators which are consistent with the upwind differencing are locally introduced when transonic shock transition is detected. Schemes thus constructed are suitable for shockcapturing calculations. The stability and the global order of accuracy of the proposed schemes are examined. Numerical experiments for the inviscid Burgers equation and the compressible Euler equations in one and two space dimensions involving various situations of aerodynamic interest are included and compared.

50 CFR 665.2 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Relation to other laws. 665.2 Section 665.2 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... other laws. NMFS recognizes that any state law pertaining to vessels registered under the laws of that...

50 CFR 660.2 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Relation to other laws. 660.2 Section 660.2 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... other laws. (a) NMFS recognizes that any state law pertaining to vessels registered under the laws of...

Nonlinear Conservation Laws and Finite Volume Methods

NASA Astrophysics Data System (ADS)

Leveque, Randall J.

Introduction Software Notation Classification of Differential Equations Derivation of Conservation Laws The Euler Equations of Gas Dynamics Dissipative Fluxes Source Terms Radiative Transfer and Isothermal Equations Multi-dimensional Conservation Laws The Shock Tube Problem Mathematical Theory of Hyperbolic Systems Scalar Equations Linear Hyperbolic Systems Nonlinear Systems The Riemann Problem for the Euler Equations Numerical Methods in One Dimension Finite Difference Theory Finite Volume Methods Importance of Conservation Form - Incorrect Shock Speeds Numerical Flux Functions Godunov's Method Approximate Riemann Solvers High-Resolution Methods Other Approaches Boundary Conditions Source Terms and Fractional Steps Unsplit Methods Fractional Step Methods General Formulation of Fractional Step Methods Stiff Source Terms Quasi-stationary Flow and Gravity Multi-dimensional Problems Dimensional Splitting Multi-dimensional Finite Volume Methods Grids and Adaptive Refinement Computational Difficulties Low-Density Flows Discrete Shocks and Viscous Profiles Start-Up Errors Wall Heating Slow-Moving Shocks Grid Orientation Effects Grid-Aligned Shocks Magnetohydrodynamics The MHD Equations One-Dimensional MHD Solving the Riemann Problem Nonstrict Hyperbolicity Stiffness The Divergence of B Riemann Problems in Multi-dimensional MHD Staggered Grids The 8-Wave Riemann Solver Relativistic Hydrodynamics Conservation Laws in Spacetime The Continuity Equation The 4-Momentum of a Particle The Stress-Energy Tensor Finite Volume Methods Multi-dimensional Relativistic Flow Gravitation and General Relativity References

On hydrostatic flows in isentropic coordinates

NASA Astrophysics Data System (ADS)

Bokhove, Onno

2000-01-01

The hydrostatic primitive equations of motion which have been used in large-scale weather prediction and climate modelling over the last few decades are analysed with variational methods in an isentropic Eulerian framework. The use of material isentropic coordinates for the Eulerian hydrostatic equations is known to have distinct conceptual advantages since fluid motion is, under inviscid and statically stable circumstances, confined to take place on quasi-horizontal isentropic surfaces. First, an Eulerian isentropic Hamilton's principle, expressed in terms of fluid parcel variables, is therefore derived by transformation of a Lagrangian Hamilton's principle to an Eulerian one. This Eulerian principle explicitly describes the boundary dynamics of the time-dependent domain in terms of advection of boundary isentropes sB; these are the values the isentropes have at their intersection with the (lower) boundary. A partial Legendre transform for only the interior variables yields an Eulerian ‘action’ principle. Secondly, Noether's theorem is used to derive energy and potential vorticity conservation from the Eulerian Hamilton's principle. Thirdly, these conservation laws are used to derive a wave-activity invariant which is second-order in terms of small-amplitude disturbances relative to a resting or moving basic state. Linear stability criteria are derived but only for resting basic states. In mid-latitudes a time- scale separation between gravity and vortical modes occurs. Finally, this time-scale separation suggests that conservative geostrophic and ageostrophic approximations can be made to the Eulerian action principle for hydrostatic flows. Approximations to Eulerian variational principles may be more advantageous than approximations to Lagrangian ones because non-dimensionalization and scaling tend to be based on Eulerian estimates of the characteristic scales involved. These approximations to the stratified hydrostatic formulation extend previous approximations to the shallow- water equations. An explicit variational derivation is given of an isentropic version of Hoskins & Bretherton's model for atmospheric fronts.

Relaxation approximations to second-order traffic flow models by high-resolution schemes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikolos, I.K.; Delis, A.I.; Papageorgiou, M.

2015-03-10

A relaxation-type approximation of second-order non-equilibrium traffic models, written in conservation or balance law form, is considered. Using the relaxation approximation, the nonlinear equations are transformed to a semi-linear diagonilizable problem with linear characteristic variables and stiff source terms with the attractive feature that neither Riemann solvers nor characteristic decompositions are in need. In particular, it is only necessary to provide the flux and source term functions and an estimate of the characteristic speeds. To discretize the resulting relaxation system, high-resolution reconstructions in space are considered. Emphasis is given on a fifth-order WENO scheme and its performance. The computations reportedmore » demonstrate the simplicity and versatility of relaxation schemes as numerical solvers.« less

The Schwinger Model on S 1: Hamiltonian Formulation, Vacuum and Anomaly

NASA Astrophysics Data System (ADS)

Stuart, David

2014-12-01

We present a Hamiltonian formulation of the Schwinger model with spatial domain taken to be the circle. It is shown that, in Coulomb gauge, the Hamiltonian is a semi-bounded, self-adjoint operator which is invariant under the group of large gauge transformations. There is a nontrivial action of on fermionic Fock space and its vacuum. This action plays a role analogous to that played by the spectral flow in the infinite Dirac sea formalism. The formulation allows (1) a description of the anomaly and its relation to the group action, and (2) an explicit identification of the vacuum. The anomaly in the chiral conservation law appears as a consequence of insisting upon semi-boundedness and gauge invariance of the quantized Hamiltonian.

7 CFR 1470.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., tribal, or territorial law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district... practices and conservation management systems. It contains detailed information on the conservation of soil...

7 CFR 1470.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., tribal, or territorial law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district... practices and conservation management systems. It contains detailed information on the conservation of soil...

7 CFR 1470.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., tribal, or territorial law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district... practices and conservation management systems. It contains detailed information on the conservation of soil...

The Development of Knowledge and Awareness of Environmental Laws and Participation in Environmental Conservation of Probationers

ERIC Educational Resources Information Center

Wanlu, Somchai; Singseewo, Adisak; Suksringarm, Paitool

2015-01-01

This research aimed to develop knowledge and awareness about environmental laws and participation in environmental conservation of probationers in MahaSarakham Province, Thailand. This study was divided into 3 stages. Stage 1: was the development of a training manual and construction of training evaluation instruments which consisted of a…

A (2+1)-dimensional Korteweg-de Vries type equation in water waves: Lie symmetry analysis; multiple exp-function method; conservation laws

NASA Astrophysics Data System (ADS)

Adem, Abdullahi Rashid

2016-05-01

We consider a (2+1)-dimensional Korteweg-de Vries type equation which models the shallow-water waves, surface and internal waves. In the analysis, we use the Lie symmetry method and the multiple exp-function method. Furthermore, conservation laws are computed using the multiplier method.

Density Large Deviations for Multidimensional Stochastic Hyperbolic Conservation Laws

NASA Astrophysics Data System (ADS)

Barré, J.; Bernardin, C.; Chetrite, R.

2018-02-01

We investigate the density large deviation function for a multidimensional conservation law in the vanishing viscosity limit, when the probability concentrates on weak solutions of a hyperbolic conservation law. When the mobility and diffusivity matrices are proportional, i.e. an Einstein-like relation is satisfied, the problem has been solved in Bellettini and Mariani (Bull Greek Math Soc 57:31-45, 2010). When this proportionality does not hold, we compute explicitly the large deviation function for a step-like density profile, and we show that the associated optimal current has a non trivial structure. We also derive a lower bound for the large deviation function, valid for a more general weak solution, and leave the general large deviation function upper bound as a conjecture.

Lie Symmetry Analysis, Analytical Solutions, and Conservation Laws of the Generalised Whitham-Broer-Kaup-Like Equations

NASA Astrophysics Data System (ADS)

Wang, Xiu-Bin; Tian, Shou-Fu; Qin, Chun-Yan; Zhang, Tian-Tian

2017-03-01

In this article, a generalised Whitham-Broer-Kaup-Like (WBKL) equations is investigated, which can describe the bidirectional propagation of long waves in shallow water. The equations can be reduced to the dispersive long wave equations, variant Boussinesq equations, Whitham-Broer-Kaup-Like equations, etc. The Lie symmetry analysis method is used to consider the vector fields and optimal system of the equations. The similarity reductions are given on the basic of the optimal system. Furthermore, the power series solutions are derived by using the power series theory. Finally, based on a new theorem of conservation laws, the conservation laws associated with symmetries of this equations are constructed with a detailed derivation.

The P1-RKDG method for two-dimensional Euler equations of gas dynamics

NASA Technical Reports Server (NTRS)

Cockburn, Bernardo; Shu, Chi-Wang

1991-01-01

A class of nonlinearly stable Runge-Kutta local projection discontinuous Galerkin (RKDG) finite element methods for conservation laws is investigated. Two dimensional Euler equations for gas dynamics are solved using P1 elements. The generalization of the local projections, which for scalar nonlinear conservation laws was designed to satisfy a local maximum principle, to systems of conservation laws such as the Euler equations of gas dynamics using local characteristic decompositions is discussed. Numerical examples include the standard regular shock reflection problem, the forward facing step problem, and the double Mach reflection problem. These preliminary numerical examples are chosen to show the capacity of the approach to obtain nonlinearly stable results comparable with the modern nonoscillatory finite difference methods.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sibiryakov, B. P., E-mail: sibiryakovbp@ipgg.sbras.ru; Novosibirsk State University, Novosibirsk, 630090

This paper studies properties of a continuum with structure. The characteristic size of the structure governs the fact that difference relations are nonautomatically transformed into differential ones. It is impossible to consider an infinitesimal volume of a body, to which the major conservation laws could be applied, because the minimum representative volume of the body must contain at least a few elementary microstructures. The corresponding equations of motion are equations of infinite order, solutions of which include, along with usual sound waves, unusual waves with abnormally low velocities without a lower limit. It is shown that in such media weakmore » perturbations can increase or decrease outside the limits. The number of complex roots of the corresponding dispersion equation, which can be interpreted as the number of unstable solutions, depends on the specific surface of cracks and is an almost linear dependence on a logarithmic scale, as in the seismological Gutenberg–Richter law. If the distance between one pore (crack) to another one is a random value with some distribution, we must write another dispersion equation and examine different scenarios depending on the statistical characteristics of the random distribution. In this case, there are sufficient deviations from the Gutenberg–Richter law and this theoretical result corresponds to some field and laboratory observations.« less

Multiphase wavetrains, singular wave interactions and the emergence of the Korteweg–de Vries equation

PubMed Central

Bridges, Thomas J.

2016-01-01

Multiphase wavetrains are multiperiodic travelling waves with a set of distinct wavenumbers and distinct frequencies. In conservative systems, such families are associated with the conservation of wave action or other conservation law. At generic points (where the Jacobian of the wave action flux is non-degenerate), modulation of the wavetrain leads to the dispersionless multiphase conservation of wave action. The main result of this paper is that modulation of the multiphase wavetrain, when the Jacobian of the wave action flux vector is singular, morphs the vector-valued conservation law into the scalar Korteweg–de Vries (KdV) equation. The coefficients in the emergent KdV equation have a geometrical interpretation in terms of projection of the vector components of the conservation law. The theory herein is restricted to two phases to simplify presentation, with extensions to any finite dimension discussed in the concluding remarks. Two applications of the theory are presented: a coupled nonlinear Schrödinger equation and two-layer shallow-water hydrodynamics with a free surface. Both have two-phase solutions where criticality and the properties of the emergent KdV equation can be determined analytically. PMID:28119546

7 CFR 1465.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... law for the express purpose of developing and carrying out a local soil and water conservation program. Such district or unit of government may be referred to as a “conservation district,” “soil conservation district,” “soil and water conservation district,” “resource conservation district,” “natural resource...

A New Runge-Kutta Discontinuous Galerkin Method with Conservation Constraint to Improve CFL Condition for Solving Conservation Laws

PubMed Central

Xu, Zhiliang; Chen, Xu-Yan; Liu, Yingjie

2014-01-01

We present a new formulation of the Runge-Kutta discontinuous Galerkin (RKDG) method [9, 8, 7, 6] for solving conservation Laws with increased CFL numbers. The new formulation requires the computed RKDG solution in a cell to satisfy additional conservation constraint in adjacent cells and does not increase the complexity or change the compactness of the RKDG method. Numerical computations for solving one-dimensional and two-dimensional scalar and systems of nonlinear hyperbolic conservation laws are performed with approximate solutions represented by piecewise quadratic and cubic polynomials, respectively. The hierarchical reconstruction [17, 33] is applied as a limiter to eliminate spurious oscillations in discontinuous solutions. From both numerical experiments and the analytic estimate of the CFL number of the newly formulated method, we find that: 1) this new formulation improves the CFL number over the original RKDG formulation by at least three times or more and thus reduces the overall computational cost; and 2) the new formulation essentially does not compromise the resolution of the numerical solutions of shock wave problems compared with ones computed by the RKDG method. PMID:25414520

Different realizations of Cooper-Frye sampling with conservation laws

NASA Astrophysics Data System (ADS)

Schwarz, C.; Oliinychenko, D.; Pang, L.-G.; Ryu, S.; Petersen, H.

2018-01-01

Approaches based on viscous hydrodynamics for the hot and dense stage and hadronic transport for the final dilute rescattering stage are successfully applied to the dynamic description of heavy ion reactions at high beam energies. One crucial step in such hybrid approaches is the so-called particlization, which is the transition between the hydrodynamic description and the microscopic degrees of freedom. For this purpose, individual particles are sampled on the Cooper-Frye hypersurface. In this work, four different realizations of the sampling algorithms are compared, with three of them incorporating the global conservation laws of quantum numbers in each event. The algorithms are compared within two types of scenarios: a simple ‘box’ hypersurface consisting of only one static cell and a typical particlization hypersurface for Au+Au collisions at \\sqrt{{s}{NN}}=200 {GeV}. For all algorithms the mean multiplicities (or particle spectra) remain unaffected by global conservation laws in the case of large volumes. In contrast, the fluctuations of the particle numbers are affected considerably. The fluctuations of the newly developed SPREW algorithm based on the exponential weight, and the recently suggested SER algorithm based on ensemble rejection, are smaller than those without conservation laws and agree with the expectation from the canonical ensemble. The previously applied mode sampling algorithm produces dramatically larger fluctuations than expected in the corresponding microcanonical ensemble, and therefore should be avoided in fluctuation studies. This study might be of interest for the investigation of particle fluctuations and correlations, e.g. the suggested signatures for a phase transition or a critical endpoint, in hybrid approaches that are affected by global conservation laws.

A Practical Example Aiding Understanding Momentum in 1D: The Water Gun Experiment

ERIC Educational Resources Information Center

MacLeod, Katarin

2007-01-01

The law of conservation of momentum is one that students often have difficulties understanding. This experiment allows students to use childhood toys to examine and calculate the muzzle velocity of their favourite water gun by using an air track, a spark timer or data logger and the law of conservation of momentum in a one-dimensional case, a…

Helicity and other conservation laws in perfect fluid motion

NASA Astrophysics Data System (ADS)

Serre, Denis

2018-03-01

In this review paper, we discuss helicity from a geometrical point of view and see how it applies to the motion of a perfect fluid. We discuss its relation with the Hamiltonian structure, and then its extension to arbitrary space dimensions. We also comment about the existence of additional conservation laws for the Euler equation, and its unlikely integrability in Liouville's sense.

Iniciativa de ley federal del patrimonio cultural de la nacion (Draft of Federal Law for the Cultural Heritage of the Nation).

ERIC Educational Resources Information Center

Mexico.

This document is an English-language abstract (approximately 1,500 words) of the draft of a law for the preservation of Mexican national heritage, particularly for the protection, conservation, and recuperation of cultural objects. The document consists of twelve chapters and six articles. Chapter 1 declares the protection, conservation,…

An analysis of finite-difference and finite-volume formulations of conservation laws

NASA Technical Reports Server (NTRS)

Vinokur, Marcel

1986-01-01

Finite-difference and finite-volume formulations are analyzed in order to clear up the confusion concerning their application to the numerical solution of conservation laws. A new coordinate-free formulation of systems of conservation laws is developed, which clearly distinguishes the role of physical vectors from that of algebraic vectors which characterize the system. The analysis considers general types of equations--potential, Euler, and Navier-Stokes. Three-dimensional unsteady flows with time-varying grids are described using a single, consistent nomeclature for both formulations. Grid motion due to a non-inertial reference frame as well as flow adaptation is covered. In comparing the two formulations, it is found useful to distinguish between differences in numerical methods and differences in grid definition. The former plays a role for non-Cartesian grids, and results in only cosmetic differences in the manner in which geometric terms are handled. The differences in grid definition for the two formulations is found to be more important, since it affects the manner in which boundary conditions, zonal procedures, and grid singularities are handled at computational boundaries. The proper interpretation of strong and weak conservation-law forms for quasi-one-dimensional and axisymmetric flows is brought out.

An analysis of finite-difference and finite-volume formulations of conservation laws

NASA Technical Reports Server (NTRS)

Vinokur, Marcel

1989-01-01

Finite-difference and finite-volume formulations are analyzed in order to clear up the confusion concerning their application to the numerical solution of conservation laws. A new coordinate-free formulation of systems of conservation laws is developed, which clearly distinguishes the role of physical vectors from that of algebraic vectors which characterize the system. The analysis considers general types of equations: potential, Euler, and Navier-Stokes. Three-dimensional unsteady flows with time-varying grids are described using a single, consistent nomenclature for both formulations. Grid motion due to a non-inertial reference frame as well as flow adaptation is covered. In comparing the two formulations, it is found useful to distinguish between differences in numerical methods and differences in grid definition. The former plays a role for non-Cartesian grids, and results in only cosmetic differences in the manner in which geometric terms are handled. The differences in grid definition for the two formulations is found to be more important, since it affects the manner in which boundary conditions, zonal procedures, and grid singularities are handled at computational boundaries. The proper interpretation of strong and weak conservation-law forms for quasi-one-dimensional and axisymmetric flows is brought out.

Effects of zonal flows on correlation between energy balance and energy conservation associated with nonlinear nonviscous atmospheric dynamics in a thin rotating spherical shell

NASA Astrophysics Data System (ADS)

Ibragimov, Ranis N.

2018-03-01

The nonlinear Euler equations are used to model two-dimensional atmosphere dynamics in a thin rotating spherical shell. The energy balance is deduced on the basis of two classes of functorially independent invariant solutions associated with the model. It it shown that the energy balance is exactly the conservation law for one class of the solutions whereas the second class of invariant solutions provides and asymptotic convergence of the energy balance to the conservation law.

High-Order Entropy Stable Finite Difference Schemes for Nonlinear Conservation Laws: Finite Domains

NASA Technical Reports Server (NTRS)

Fisher, Travis C.; Carpenter, Mark H.

2013-01-01

Developing stable and robust high-order finite difference schemes requires mathematical formalism and appropriate methods of analysis. In this work, nonlinear entropy stability is used to derive provably stable high-order finite difference methods with formal boundary closures for conservation laws. Particular emphasis is placed on the entropy stability of the compressible Navier-Stokes equations. A newly derived entropy stable weighted essentially non-oscillatory finite difference method is used to simulate problems with shocks and a conservative, entropy stable, narrow-stencil finite difference approach is used to approximate viscous terms.

Zipf's Law for Word Frequencies: Word Forms versus Lemmas in Long Texts.

PubMed

Corral, Álvaro; Boleda, Gemma; Ferrer-i-Cancho, Ramon

2015-01-01

Zipf's law is a fundamental paradigm in the statistics of written and spoken natural language as well as in other communication systems. We raise the question of the elementary units for which Zipf's law should hold in the most natural way, studying its validity for plain word forms and for the corresponding lemma forms. We analyze several long literary texts comprising four languages, with different levels of morphological complexity. In all cases Zipf's law is fulfilled, in the sense that a power-law distribution of word or lemma frequencies is valid for several orders of magnitude. We investigate the extent to which the word-lemma transformation preserves two parameters of Zipf's law: the exponent and the low-frequency cut-off. We are not able to demonstrate a strict invariance of the tail, as for a few texts both exponents deviate significantly, but we conclude that the exponents are very similar, despite the remarkable transformation that going from words to lemmas represents, considerably affecting all ranges of frequencies. In contrast, the low-frequency cut-offs are less stable, tending to increase substantially after the transformation.

Lectures series in computational fluid dynamics

NASA Technical Reports Server (NTRS)

Thompson, Kevin W.

1987-01-01

The lecture notes cover the basic principles of computational fluid dynamics (CFD). They are oriented more toward practical applications than theory, and are intended to serve as a unified source for basic material in the CFD field as well as an introduction to more specialized topics in artificial viscosity and boundary conditions. Each chapter in the test is associated with a videotaped lecture. The basic properties of conservation laws, wave equations, and shock waves are described. The duality of the conservation law and wave representations is investigated, and shock waves are examined in some detail. Finite difference techniques are introduced for the solution of wave equations and conservation laws. Stability analysis for finite difference approximations are presented. A consistent description of artificial viscosity methods are provided. Finally, the problem of nonreflecting boundary conditions are treated.

78 FR 41959 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

... Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of permit modification under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National Science Foundation (NSF) is... Conservation Act of 1978. NSF has published regulations under the Antarctic Conservation Act at Title 45 Part...

Quasi-local conserved charges in the Einstein-Maxwell theory

NASA Astrophysics Data System (ADS)

Setare, M. R.; Adami, H.

2017-05-01

In this paper we consider the Einstein-Maxwell theory and define a combined transformation composed of diffeomorphism and U(1) gauge transformation. For generality, we assume that the generator χ of such transformation is field-dependent. We define the extended off-shell ADT current and then off-shell ADT charge such that they are conserved off-shell for the asymptotically field-dependent symmetry generator χ. Then, we define the conserved charge corresponding to the asymptotically field-dependent symmetry generator χ. We apply the presented method to find the conserved charges of the asymptotically AdS3 spacetimes in the context of the Einstein-Maxwell theory in three dimensions. Although the usual proposal for the quasi local charges provides divergent global charges for the Einstein-Maxwell theory with negative cosmological constant in three dimensions, here we avoid this problem by introducing proposed combined transformation χ

A Structuralist Approach to Television Criticism.

ERIC Educational Resources Information Center

Robards, Brooks

Although television is highly dependent on language and semiotic analysis, its form can best be analyzed through the structural notion of transformation. The critic's task becomes the articulation of structural laws intrinsic to television. One such law has to do with how television structures time. Television programming transforms action into…

Overcoming Challenges in Kinetic Modeling of Magnetized Plasmas and Vacuum Electronic Devices

NASA Astrophysics Data System (ADS)

Omelchenko, Yuri; Na, Dong-Yeop; Teixeira, Fernando

2017-10-01

We transform the state-of-the art of plasma modeling by taking advantage of novel computational techniques for fast and robust integration of multiscale hybrid (full particle ions, fluid electrons, no displacement current) and full-PIC models. These models are implemented in 3D HYPERS and axisymmetric full-PIC CONPIC codes. HYPERS is a massively parallel, asynchronous code. The HYPERS solver does not step fields and particles synchronously in time but instead executes local variable updates (events) at their self-adaptive rates while preserving fundamental conservation laws. The charge-conserving CONPIC code has a matrix-free explicit finite-element (FE) solver based on a sparse-approximate inverse (SPAI) algorithm. This explicit solver approximates the inverse FE system matrix (``mass'' matrix) using successive sparsity pattern orders of the original matrix. It does not reduce the set of Maxwell's equations to a vector-wave (curl-curl) equation of second order but instead utilizes the standard coupled first-order Maxwell's system. We discuss the ability of our codes to accurately and efficiently account for multiscale physical phenomena in 3D magnetized space and laboratory plasmas and axisymmetric vacuum electronic devices.

Metric Theories of Gravity: Perturbations and Conservation Laws

NASA Astrophysics Data System (ADS)

Petrov, Alexander N.; Kopeikin, Sergei M.; Lompay, Robert R.; Tekin, Bayram

2017-04-01

By focusing on the mostly used variational methods, this monograph aspires to give a unified description and comparison of various ways of constructing conserved quantities for perturbations and to study symmetries in general relativity and modified theories of gravity. The main emphasis lies on the field-theoretical covariant formulation of perturbations, the canonical Noether approach and the Belinfante procedure of symmetrisation. The general formalism is applied to build the gauge-invariant cosmological perturbation theory, conserved currents and superpotentials to describe physically important solutions of gravity theories. Meticulous attention is given to the construction of conserved quantities in asymptotically-flat spacetimes as well as in asymptotically constant curvature spacetimes such as the Anti-de Sitter space. Significant part of the book can be used in graduate courses on conservation laws in general relativity.

An optimization-based approach for high-order accurate discretization of conservation laws with discontinuous solutions

NASA Astrophysics Data System (ADS)

Zahr, M. J.; Persson, P.-O.

2018-07-01

This work introduces a novel discontinuity-tracking framework for resolving discontinuous solutions of conservation laws with high-order numerical discretizations that support inter-element solution discontinuities, such as discontinuous Galerkin or finite volume methods. The proposed method aims to align inter-element boundaries with discontinuities in the solution by deforming the computational mesh. A discontinuity-aligned mesh ensures the discontinuity is represented through inter-element jumps while smooth basis functions interior to elements are only used to approximate smooth regions of the solution, thereby avoiding Gibbs' phenomena that create well-known stability issues. Therefore, very coarse high-order discretizations accurately resolve the piecewise smooth solution throughout the domain, provided the discontinuity is tracked. Central to the proposed discontinuity-tracking framework is a discrete PDE-constrained optimization formulation that simultaneously aligns the computational mesh with discontinuities in the solution and solves the discretized conservation law on this mesh. The optimization objective is taken as a combination of the deviation of the finite-dimensional solution from its element-wise average and a mesh distortion metric to simultaneously penalize Gibbs' phenomena and distorted meshes. It will be shown that our objective function satisfies two critical properties that are required for this discontinuity-tracking framework to be practical: (1) possesses a local minima at a discontinuity-aligned mesh and (2) decreases monotonically to this minimum in a neighborhood of radius approximately h / 2, whereas other popular discontinuity indicators fail to satisfy the latter. Another important contribution of this work is the observation that traditional reduced space PDE-constrained optimization solvers that repeatedly solve the conservation law at various mesh configurations are not viable in this context since severe overshoot and undershoot in the solution, i.e., Gibbs' phenomena, may make it impossible to solve the discrete conservation law on non-aligned meshes. Therefore, we advocate a gradient-based, full space solver where the mesh and conservation law solution converge to their optimal values simultaneously and therefore never require the solution of the discrete conservation law on a non-aligned mesh. The merit of the proposed method is demonstrated on a number of one- and two-dimensional model problems including the L2 projection of discontinuous functions, Burgers' equation with a discontinuous source term, transonic flow through a nozzle, and supersonic flow around a bluff body. We demonstrate optimal O (h p + 1) convergence rates in the L1 norm for up to polynomial order p = 6 and show that accurate solutions can be obtained on extremely coarse meshes.

Power-law behaviour evaluation from foreign exchange market data using a wavelet transform method

NASA Astrophysics Data System (ADS)

Wei, H. L.; Billings, S. A.

2009-09-01

Numerous studies in the literature have shown that the dynamics of many time series including observations in foreign exchange markets exhibit scaling behaviours. A simple new statistical approach, derived from the concept of the continuous wavelet transform correlation function (WTCF), is proposed for the evaluation of power-law properties from observed data. The new method reveals that foreign exchange rates obey power-laws and thus belong to the class of self-similarity processes.

76 FR 30186 - Proposed Information Collection; Migratory Birds and Wetlands Conservation Grant Programs

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

... 7C] Proposed Information Collection; Migratory Birds and Wetlands Conservation Grant Programs AGENCY...). SUPPLEMENTARY INFORMATION: I. Abstract The Division of Bird Habitat Conservation administers grant programs... Migratory Bird Conservation Act (NMBCA), Public Law 106-247. Currently, information that we collect for...

Convergence of generalized MUSCL schemes

NASA Technical Reports Server (NTRS)

Osher, S.

1984-01-01

Semi-discrete generalizations of the second order extension of Godunov's scheme, known as the MUSCL scheme, are constructed, starting with any three point E scheme. They are used to approximate scalar conservation laws in one space dimension. For convex conservation laws, each member of a wide class is proven to be a convergent approximation to the correct physical solution. Comparison with another class of high resolution convergent schemes is made.

High-resolution schemes for hyperbolic conservation laws

NASA Technical Reports Server (NTRS)

Harten, A.

1982-01-01

A class of new explicit second order accurate finite difference schemes for the computation of weak solutions of hyperbolic conservation laws is presented. These highly nonlinear schemes are obtained by applying a nonoscillatory first order accurae scheme to an appropriately modified flux function. The so derived second order accurate schemes achieve high resolution while preserving the robustness of the original nonoscillatory first order accurate scheme.

LETTER TO THE EDITOR: Bicomplexes and conservation laws in non-Abelian Toda models

NASA Astrophysics Data System (ADS)

Gueuvoghlanian, E. P.

2001-08-01

A bicomplex structure is associated with the Leznov-Saveliev equation of integrable models. The linear problem associated with the zero-curvature condition is derived in terms of the bicomplex linear equation. The explicit example of a non-Abelian conformal affine Toda model is discussed in detail and its conservation laws are derived from the zero-curvature representation of its equation of motion.

Some observations on boundary conditions for numerical conservation laws

NASA Technical Reports Server (NTRS)

Kamowitz, David

1988-01-01

Four choices of outflow boundary conditions are considered for numerical conservation laws. All four methods are stable for linear problems, for which examples are presented where either a boundary layer forms or the numerical scheme, together with the boundary condition, is unstable due to the formation of a reflected shock. A simple heuristic argument is presented for determining the suitability of the boundary condition.

Vehicle energy conservation indicating device and process for use

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crump, J.M.

A vehicle energy conservation indicating device comprises an integrated instrument cluster functioning basically as a nomographic computing mechanism. The odometer distance traveled indicator computing mechanism is linked with the fuel indicating gauge mechanism such that a three variable equation computing mechanism is obtained. The three variables are distance traveled, quantity of fuel consumed and distance traveled per unit of fuel consumed. Energy conservation is achieved by operating the vehicle under such performance conditions as to produce the highest possible value for distance traveled per unit of fuel consumed. The instrument panel cluster brings the operator's attention to focus upon andmore » continuously stimulated to conserving energy. Furthermore, the vehicle energy conservation indicating device can be adapted for recording these performance variables on tape type print out. The speedometer advises the vehicle operator when he is obeying or breaking the speed laws which are enforced and monitored by the police with specific punishment prescribed for violations of the law. At this time there is no comparable procedure for enforcing vehicle energy conservation. Thus, this direct read out of distance traveled per unit of energy will moderate the operation in an analogous manner similar to subliminal advertising. This device becomes the focal point of the instrument panel along with the speedometer, thereby providing constant motivation to obey both the speed and energy conservation laws.« less

Nonlinear Binormal Flow of Vortex Filaments

NASA Astrophysics Data System (ADS)

Strong, Scott; Carr, Lincoln

2015-11-01

With the current advances in vortex imaging of Bose-Einstein condensates occurring at the Universities of Arizona, São Paulo and Cambridge, interest in vortex filament dynamics is experiencing a resurgence. Recent simulations, Salman (2013), depict dissipative mechanisms resulting from vortex ring emissions and Kelvin wave generation associated with vortex self-intersections. As the local induction approximation fails to capture reconnection events, it lacks a similar dissipative mechanism. On the other hand, Strong&Carr (2012) showed that the exact representation of the velocity field induced by a curved segment of vortex contains higher-order corrections expressed in powers of curvature. This nonlinear binormal flow can be transformed, Hasimoto (1972), into a fully nonlinear equation of Schrödinger type. Continued transformation, Madelung (1926), reveals that the filament's square curvature obeys a quasilinear scalar conservation law with source term. This implies a broader range of filament dynamics than is possible with the integrable linear binormal flow. In this talk we show the affect higher-order corrections have on filament dynamics and discuss physical scales for which they may be witnessed in future experiments. Partially supported by NSF.

Illusion induced overlapped optics.

PubMed

Zang, XiaoFei; Shi, Cheng; Li, Zhou; Chen, Lin; Cai, Bin; Zhu, YiMing; Zhu, HaiBin

2014-01-13

The traditional transformation-based cloak seems like it can only hide objects by bending the incident electromagnetic waves around the hidden region. In this paper, we prove that invisible cloaks can be applied to realize the overlapped optics. No matter how many in-phase point sources are located in the hidden region, all of them can overlap each other (this can be considered as illusion effect), leading to the perfect optical interference effect. In addition, a singular parameter-independent cloak is also designed to obtain quasi-overlapped optics. Even more amazing of overlapped optics is that if N identical separated in-phase point sources covered with the illusion media, the total power outside the transformation region is N2I0 (not NI0) (I0 is the power of just one point source, and N is the number point sources), which seems violating the law of conservation of energy. A theoretical model based on interference effect is proposed to interpret the total power of these two kinds of overlapped optics effects. Our investigation may have wide applications in high power coherent laser beams, and multiple laser diodes, and so on.

78 FR 28000 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-13

... Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National Science... regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the Antarctic...

77 FR 67407 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-09

... Conservation Act of 1978 AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National Science... regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the Antarctic...

41 CFR 101-25.112 - Energy conservation policy.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true Energy conservation...-General Policies § 101-25.112 Energy conservation policy. (a) Agency officials responsible for procurement..., which has been established pursuant to Public Law 94-163, Energy Policy and Conservation Act. (b) With...

41 CFR 101-25.112 - Energy conservation policy.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Energy conservation...-General Policies § 101-25.112 Energy conservation policy. (a) Agency officials responsible for procurement..., which has been established pursuant to Public Law 94-163, Energy Policy and Conservation Act. (b) With...

41 CFR 101-25.112 - Energy conservation policy.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false Energy conservation...-General Policies § 101-25.112 Energy conservation policy. (a) Agency officials responsible for procurement..., which has been established pursuant to Public Law 94-163, Energy Policy and Conservation Act. (b) With...

41 CFR 101-25.112 - Energy conservation policy.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true Energy conservation...-General Policies § 101-25.112 Energy conservation policy. (a) Agency officials responsible for procurement..., which has been established pursuant to Public Law 94-163, Energy Policy and Conservation Act. (b) With...

41 CFR 101-25.112 - Energy conservation policy.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Energy conservation...-General Policies § 101-25.112 Energy conservation policy. (a) Agency officials responsible for procurement..., which has been established pursuant to Public Law 94-163, Energy Policy and Conservation Act. (b) With...

Effects of introduction of new resources and fragmentation of existing resources on limiting wealth distribution in asset exchange models

NASA Astrophysics Data System (ADS)

Ali Saif, M.; Gade, Prashant M.

2009-03-01

Pareto law, which states that wealth distribution in societies has a power-law tail, has been the subject of intensive investigations in the statistical physics community. Several models have been employed to explain this behavior. However, most of the agent based models assume the conservation of number of agents and wealth. Both these assumptions are unrealistic. In this paper, we study the limiting wealth distribution when one or both of these assumptions are not valid. Given the universality of the law, we have tried to study the wealth distribution from the asset exchange models point of view. We consider models in which (a) new agents enter the market at a constant rate (b) richer agents fragment with higher probability introducing newer agents in the system (c) both fragmentation and entry of new agents is taking place. While models (a) and (c) do not conserve total wealth or number of agents, model (b) conserves total wealth. All these models lead to a power-law tail in the wealth distribution pointing to the possibility that more generalized asset exchange models could help us to explain the emergence of a power-law tail in wealth distribution.

50 CFR 640.3 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Relation to other laws. 640.3 Section 640.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Provisions § 640.3 Relation to other laws. (a) The relation of this part to other laws is set forth in § 600...

50 CFR 648.3 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Relation to other laws. 648.3 Section 648.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Relation to other laws. (a) The relation of this part to other laws is set forth in § 600.705. (b) Nothing...

50 CFR 648.3 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Relation to other laws. 648.3 Section 648.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Relation to other laws. (a) The relation of this part to other laws is set forth in § 600.705. (b) Nothing...

50 CFR 640.3 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Relation to other laws. 640.3 Section 640.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Provisions § 640.3 Relation to other laws. (a) The relation of this part to other laws is set forth in § 600...

50 CFR 660.403 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Relation to other laws. 660.403 Section 660.403 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 660.403 Relation to other laws. (a) The relation of this part to other laws is set forth in § 600.705...

50 CFR 654.3 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Relation to other laws. 654.3 Section 654.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... to other laws. (a) The relation of this part to other laws is set forth in § 600.705 of this chapter...

50 CFR 648.3 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Relation to other laws. 648.3 Section 648.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Relation to other laws. (a) The relation of this part to other laws is set forth in § 600.705. (b) Nothing...

A conserved post-transcriptional BMP2 switch in lung cells.

PubMed

Jiang, Shan; Fritz, David T; Rogers, Melissa B

2010-05-15

An ultra-conserved sequence in the bone morphogenetic protein 2 (BMP2) 3' untranslated region (UTR) markedly represses BMP2 expression in non-transformed lung cells. In contrast, the ultra-conserved sequence stimulates BMP2 expression in transformed lung cells. The ultra-conserved sequence functions as a post-transcriptional cis-regulatory switch. A common single-nucleotide polymorphism (SNP, rs15705, +A1123C), which has been shown to influence human morphology, disrupts a conserved element within the ultra-conserved sequence and altered reporter gene activity in non-transformed lung cells. This polymorphism changed the affinity of the BMP2 RNA for several proteins including nucleolin, which has an increased affinity for the C allele. Elevated BMP2 synthesis is associated with increased malignancy in mouse models of lung cancer and poor lung cancer patient prognosis. Understanding the cis- and trans-regulatory factors that control BMP2 synthesis is relevant to the initiation or progression of pathologies associated with abnormal BMP2 levels. (c) 2010 Wiley-Liss, Inc.

Derivation of the Lorentz force law, the magnetic field concept and the Faraday Lenz and magnetic Gauss laws using an invariant formulation of the Lorentz transformation

NASA Astrophysics Data System (ADS)

Field, J. H.

2006-06-01

It is demonstrated how the right-hand sides of the Lorentz transformation equations may be written, in a Lorentz-invariant manner, as 4-vector scalar products. This implies the existence of invariant length intervals analogous to invariant proper time intervals. An important distinction between the physical meanings of the space time and energy momentum 4-vectors is pointed out. The formalism is shown to provide a short derivation of the Lorentz force law of classical electrodynamics, and the conventional definition of the magnetic field, in terms of spatial derivatives of the 4-vector potential, as well as the Faraday Lenz law and the Gauss law for magnetic fields. The connection between the Gauss law for the electric field and the electrodynamic Ampère law, due to the 4-vector character of the electromagnetic potential, is also pointed out.

China Report, Economic Affairs, Number 243, Energy: Status and Development -- VI

DTIC Science & Technology

1982-06-29

the enterprises. 3. We should start the work of technical transformation and equipment renovation with energy conservation as the core. At present...transformation and equipment renovation for the purpose of energy conservation. The technology and many sets of equipment used for energy consumption...true that equipment renovation and technical transformation will cost money. Compared with investment in the exploitation of energy resources, however

Lie symmetry analysis, exact solutions and conservation laws for the time fractional Caudrey-Dodd-Gibbon-Sawada-Kotera equation

NASA Astrophysics Data System (ADS)

Baleanu, Dumitru; Inc, Mustafa; Yusuf, Abdullahi; Aliyu, Aliyu Isa

2018-06-01

In this work, we investigate the Lie symmetry analysis, exact solutions and conservation laws (Cls) to the time fractional Caudrey-Dodd-Gibbon-Sawada-Kotera (CDGDK) equation with Riemann-Liouville (RL) derivative. The time fractional CDGDK is reduced to nonlinear ordinary differential equation (ODE) of fractional order. New exact traveling wave solutions for the time fractional CDGDK are obtained by fractional sub-equation method. In the reduced equation, the derivative is in Erdelyi-Kober (EK) sense. Ibragimov's nonlocal conservation method is applied to construct Cls for time fractional CDGDK.

Design and Construction of Multi-Variable Vortex-Ring Bubble Generator for Use in Interactive Exhibit

DTIC Science & Technology

2013-12-01

providing the opportunity to teach complex subjects related to stable and unstable equilibrium, stochastic systems, and conservation laws. The...bubbles through adjustment of three variables. The seal pressure, actuating pressure, and cycle time of the triggering solenoid valve each contribute to...stable and unstable equilibrium, stochastic systems, and conservation laws. The diaphragm valve designed in this thesis provides the centerpiece for

On the Total Variation of High-Order Semi-Discrete Central Schemes for Conservation Laws

NASA Technical Reports Server (NTRS)

Bryson, Steve; Levy, Doron

2004-01-01

We discuss a new fifth-order, semi-discrete, central-upwind scheme for solving one-dimensional systems of conservation laws. This scheme combines a fifth-order WENO reconstruction, a semi-discrete central-upwind numerical flux, and a strong stability preserving Runge-Kutta method. We test our method with various examples, and give particular attention to the evolution of the total variation of the approximations.

Justification of Shallow-Water Theory

NASA Astrophysics Data System (ADS)

Ostapenko, V. V.

2018-01-01

The basic conservation laws of shallow-water theory are derived from multidimensional mass and momentum integral conservation laws describing the plane-parallel flow of an ideal incompressible fluid above the horizontal bottom. This conclusion is based on the concept of hydrostatic approximation, which generalizes the concept of long-wavelength approximation and is used for justifying the applicability of the shallow-water theory in the simulation of wave flows of fluid with hydraulic bores.

Conservation laws in the quantum Hall Liouvillian theory and its generalizations

NASA Astrophysics Data System (ADS)

Moore, Joel E.

2003-06-01

It is known that the localization length scaling of noninteracting electrons near the quantum Hall plateau transition can be described in a theory of the bosonic density operators, with no reference to the underlying fermions. The resulting "Liouvillian" theory has a U(1|1) global supersymmetry as well as a hierarchy of geometric conservation laws related to the noncommutative geometry of the lowest Landau level (LLL). Approximations to the Liouvillian theory contain quite different physics from standard approximations to the underlying fermionic theory. Mean-field and large- N generalizations of the Liouvillian are shown to describe problems of noninteracting bosons that enlarge the U(1|1) supersymmetry to U(1|1)× SO( N) or U(1|1)× SU( N). These noninteracting bosonic problems are studied numerically for 2⩽ N⩽8 by Monte Carlo simulation and compared to the original N=1 Liouvillian theory. The N>1 generalizations preserve the first two of the hierarchy of geometric conservation laws, leading to logarithmic corrections at order 1/ N to the diffusive large- N limit, but do not preserve the remaining conservation laws. The emergence of nontrivial scaling at the plateau transition, in the Liouvillian approach, is shown to depend sensitively on the unusual geometry of Landau levels.

Zipf’s Law for Word Frequencies: Word Forms versus Lemmas in Long Texts

PubMed Central

Corral, Álvaro; Boleda, Gemma; Ferrer-i-Cancho, Ramon

2015-01-01

Zipf’s law is a fundamental paradigm in the statistics of written and spoken natural language as well as in other communication systems. We raise the question of the elementary units for which Zipf’s law should hold in the most natural way, studying its validity for plain word forms and for the corresponding lemma forms. We analyze several long literary texts comprising four languages, with different levels of morphological complexity. In all cases Zipf’s law is fulfilled, in the sense that a power-law distribution of word or lemma frequencies is valid for several orders of magnitude. We investigate the extent to which the word-lemma transformation preserves two parameters of Zipf’s law: the exponent and the low-frequency cut-off. We are not able to demonstrate a strict invariance of the tail, as for a few texts both exponents deviate significantly, but we conclude that the exponents are very similar, despite the remarkable transformation that going from words to lemmas represents, considerably affecting all ranges of frequencies. In contrast, the low-frequency cut-offs are less stable, tending to increase substantially after the transformation. PMID:26158787

Studying Scientific Discovery by Computer Simulation.

DTIC Science & Technology

1983-03-30

Mendel’s laws of inheritance, the law of Gay- Lussac for gaseous reactions, tile law of Dulong and Petit, the derivation of atomic weights by Avogadro...neceseary mid identify by block number) scientific discovery -ittri sic properties physical laws extensive terms data-driven heuristics intensive...terms theory-driven heuristics conservation laws 20. ABSTRACT (Continue on revere. side It necessary and identify by block number) Scientific discovery

Cosmological constant is a conserved charge

NASA Astrophysics Data System (ADS)

Chernyavsky, Dmitry; Hajian, Kamal

2018-06-01

Cosmological constant can always be considered as the on-shell value of a top form in gravitational theories. The top form is the field strength of a gauge field, and the theory enjoys a gauge symmetry. We show that cosmological constant is the charge of the global part of the gauge symmetry, and is conserved irrespective of the dynamics of the metric and other fields. In addition, we introduce its conjugate chemical potential, and prove the generalized first law of thermodynamics which includes variation of cosmological constant as a conserved charge. We discuss how our new term in the first law is related to the volume–pressure term. In parallel with the seminal Wald entropy, this analysis suggests that pressure can also be considered as a conserved charge.

Environmental Designer Drugs: When Transformation May Not Eliminate Risk

PubMed Central

2015-01-01

Environmental transformation processes, including those occurring in natural and engineered systems, do not necessarily drastically alter molecular structures of bioactive organic contaminants. While the majority of generated transformation products are likely benign, substantial conservation of structure in transformation products can imply conservation or even creation of bioactivity across multiple biological end points and thus incomplete mitigation of ecological risk. Therefore, focusing solely on parent compound removal for contaminants of higher relative risk, the most common approach to fate characterization, provides no mechanistic relationship to potential biological effects and is inadequate as a comprehensive metric for reduction of ecological risks. Here, we explore these phenomena for endocrine-active steroid hormones, focusing on examples of conserved bioactivity and related implications for fate assessment, regulatory approaches, and research opportunities. PMID:25216024

Hunting, law enforcement, and African primate conservation.

PubMed

N'Goran, Paul K; Boesch, Christophe; Mundry, Roger; N'Goran, Eliezer K; Herbinger, Ilka; Yapi, Fabrice A; Kühl, Hjalmar S

2012-06-01

Primates are regularly hunted for bushmeat in tropical forests, and systematic ecological monitoring can help determine the effect hunting has on these and other hunted species. Monitoring can also be used to inform law enforcement and managers of where hunting is concentrated. We evaluated the effects of law enforcement informed by monitoring data on density and spatial distribution of 8 monkey species in Taï National Park, Côte d'Ivoire. We conducted intensive surveys of monkeys and looked for signs of human activity throughout the park. We also gathered information on the activities of law-enforcement personnel related to hunting and evaluated the relative effects of hunting, forest cover and proximity to rivers, and conservation effort on primate distribution and density. The effects of hunting on monkeys varied among species. Red colobus monkeys (Procolobus badius) were most affected and Campbell's monkeys (Cercopithecus campbelli) were least affected by hunting. Density of monkeys irrespective of species was up to 100 times higher near a research station and tourism site in the southwestern section of the park, where there is little hunting, than in the southeastern part of the park. The results of our monitoring guided law-enforcement patrols toward zones with the most hunting activity. Such systematic coordination of ecological monitoring and law enforcement may be applicable at other sites. ©2012 Society for Conservation Biology.

For the law, neuroscience changes nothing and everything.

PubMed Central

Greene, Joshua; Cohen, Jonathan

2004-01-01

The rapidly growing field of cognitive neuroscience holds the promise of explaining the operations of the mind in terms of the physical operations of the brain. Some suggest that our emerging understanding of the physical causes of human (mis)behaviour will have a transformative effect on the law. Others argue that new neuroscience will provide only new details and that existing legal doctrine can accommodate whatever new information neuroscience will provide. We argue that neuroscience will probably have a transformative effect on the law, despite the fact that existing legal doctrine can, in principle, accommodate whatever neuroscience will tell us. New neuroscience will change the law, not by undermining its current assumptions, but by transforming people's moral intuitions about free will and responsibility. This change in moral outlook will result not from the discovery of crucial new facts or clever new arguments, but from a new appreciation of old arguments, bolstered by vivid new illustrations provided by cognitive neuroscience. We foresee, and recommend, a shift away from punishment aimed at retribution in favour of a more progressive, consequentialist approach to the criminal law. PMID:15590618

Traveling waves and conservation laws for highly nonlinear wave equations modeling Hertz chains

NASA Astrophysics Data System (ADS)

Przedborski, Michelle; Anco, Stephen C.

2017-09-01

A highly nonlinear, fourth-order wave equation that models the continuum theory of long wavelength pulses in weakly compressed, homogeneous, discrete chains with a general power-law contact interaction is studied. For this wave equation, all solitary wave solutions and all nonlinear periodic wave solutions, along with all conservation laws, are derived. The solutions are explicitly parameterized in terms of the asymptotic value of the wave amplitude in the case of solitary waves and the peak of the wave amplitude in the case of nonlinear periodic waves. All cases in which the solution expressions can be stated in an explicit analytic form using elementary functions are worked out. In these cases, explicit expressions for the total energy and total momentum for all solutions are obtained as well. The derivation of the solutions uses the conservation laws combined with an energy analysis argument to reduce the wave equation directly to a separable first-order differential equation that determines the wave amplitude in terms of the traveling wave variable. This method can be applied more generally to other highly nonlinear wave equations.

7 CFR 1465.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... document that identifies the location and timing of conservation practices that the participant agrees to... Chief of NRCS, United States Department of Agriculture (USDA), or designee. Conservation district means... law for the express purpose of developing and carrying out a local soil and water conservation program...

7 CFR 1465.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... document that identifies the location and timing of conservation practices that the participant agrees to... Chief of NRCS, United States Department of Agriculture (USDA), or designee. Conservation district means... law for the express purpose of developing and carrying out a local soil and water conservation program...

7 CFR 1465.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... document that identifies the location and timing of conservation practices that the participant agrees to... Chief of NRCS, United States Department of Agriculture (USDA), or designee. Conservation district means... law for the express purpose of developing and carrying out a local soil and water conservation program...

Nonlinear evolutions of an ultra-intense ultra-short laser pulse in a rarefied plasma through a new quasi-static theory

NASA Astrophysics Data System (ADS)

Yazdanpanah, J.

2018-02-01

In this paper, we present a new description of self-consistent wake excitation by an intense short laser pulse, based on applying the quasi-static approximation (slow variations of the pulse-envelope) in the instantaneous Lorentz-boosted pulse co-moving frame (PCMF), and best verify our results through comparison with particle-in-cell simulations. According to this theory, the plasma motion can be treated perturbatively in the PCMF due to its high initial-velocity and produces a quasi-static wakefield in this frame. The pulse envelope, on the other hand, is governed by a form of the Schrödinger equation in the PCMF, in which the wakefield acts as an effective potential. In this context, pulse evolutions are characterized by local conservation laws resulted from this equation and subjected to Lorentz transformation into the laboratory frame. Using these conservation laws, precise formulas are obtained for spatiotemporal pulse evolutions and related wakefield variations at initial stages, and new equations are derived for instantaneous group velocity and carrier frequency. In addition, based on properties of the Schrödinger equation, spectral-evolutions of the pulse are described and the emergence of an anomalous dispersion branch with linear relation ω ≈ ck (c is the light speed) is predicted. Our results are carefully discussed versus previous publications and the significance of our approach is described by showing almost all suggestive definitions of group-velocity based on energy arguments fail to reproduce our formula and correctly describe the instantaneous pulse-velocity.

Lie symmetry analysis, conservation laws and exact solutions of the time-fractional generalized Hirota-Satsuma coupled KdV system

NASA Astrophysics Data System (ADS)

Saberi, Elaheh; Reza Hejazi, S.

2018-02-01

In the present paper, Lie point symmetries of the time-fractional generalized Hirota-Satsuma coupled KdV (HS-cKdV) system based on the Riemann-Liouville derivative are obtained. Using the derived Lie point symmetries, we obtain similarity reductions and conservation laws of the considered system. Finally, some analytic solutions are furnished by means of the invariant subspace method in the Caputo sense.

On the construction and application of implicit factored schemes for conservation laws. [in computational fluid dynamics

NASA Technical Reports Server (NTRS)

Warming, R. F.; Beam, R. M.

1978-01-01

Efficient, noniterative, implicit finite difference algorithms are systematically developed for nonlinear conservation laws including purely hyperbolic systems and mixed hyperbolic parabolic systems. Utilization of a rational fraction or Pade time differencing formulas, yields a direct and natural derivation of an implicit scheme in a delta form. Attention is given to advantages of the delta formation and to various properties of one- and two-dimensional algorithms.

When Is Momentum Conserved, and What About Car Crashes in Virginia?

NASA Astrophysics Data System (ADS)

Ehrlich, Robert

2005-10-01

Many years ago I consulted on the reconstruction of an automobile accident for an attorney. After writing a report on the accident, I was deposed by the other side's attorney, and my report was challenged. One key calculation in my report made use of the conservation of momentum in the crash, and the attorney notified me that arguments involving conservation of momentum are not recognized by courts in the Commonwealth of Virginia. Apparently the situation today is more mixed, according to an accident reconstructionist I recently spoke with, who noted that about half the judges (the "more open-minded ones") do admit such arguments in court. This real-world experience with a conflict between the laws of physics and the laws of man made me reflect on whether there might be some validity to the disinclination of many judges to acknowledge a law of physics in their courtrooms.

Energy and maximum norm estimates for nonlinear conservation laws

NASA Technical Reports Server (NTRS)

Olsson, Pelle; Oliger, Joseph

1994-01-01

We have devised a technique that makes it possible to obtain energy estimates for initial-boundary value problems for nonlinear conservation laws. The two major tools to achieve the energy estimates are a certain splitting of the flux vector derivative f(u)(sub x), and a structural hypothesis, referred to as a cone condition, on the flux vector f(u). These hypotheses are fulfilled for many equations that occur in practice, such as the Euler equations of gas dynamics. It should be noted that the energy estimates are obtained without any assumptions on the gradient of the solution u. The results extend to weak solutions that are obtained as point wise limits of vanishing viscosity solutions. As a byproduct we obtain explicit expressions for the entropy function and the entropy flux of symmetrizable systems of conservation laws. Under certain circumstances the proposed technique can be applied repeatedly so as to yield estimates in the maximum norm.

On the application of subcell resolution to conservation laws with stiff source terms

NASA Technical Reports Server (NTRS)

Chang, Shih-Hung

1989-01-01

LeVeque and Yee recently investigated a one-dimensional scalar conservation law with stiff source terms modeling the reacting flow problems and discovered that for the very stiff case most of the current finite difference methods developed for non-reacting flows would produce wrong solutions when there is a propagating discontinuity. A numerical scheme, essentially nonoscillatory/subcell resolution - characteristic direction (ENO/SRCD), is proposed for solving conservation laws with stiff source terms. This scheme is a modification of Harten's ENO scheme with subcell resolution, ENO/SR. The locations of the discontinuities and the characteristic directions are essential in the design. Strang's time-splitting method is used and time evolutions are done by advancing along the characteristics. Numerical experiment using this scheme shows excellent results on the model problem of LeVeque and Yee. Comparisons of the results of ENO, ENO/SR, and ENO/SRCD are also presented.

77 FR 7281 - Energy Conservation Program: Energy Conservation Standards for Distribution Transformers

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-10

... Manufacturing Transformers H. Customer Subgroup Analysis I. Manufacturer Impact Analysis 1. Overview 2... Justification and Energy Savings 1. Economic Impacts on Customers a. Life-Cycle Cost and Payback Period b. Customer Subgroup Analysis c. Rebuttable-Presumption Payback 2. Economic Impact on Manufacturers a...

A general spectral transformation simultaneously including a Fourier transformation and a Laplace transformation

NASA Technical Reports Server (NTRS)

Marko, H.

1978-01-01

A general spectral transformation is proposed and described. Its spectrum can be interpreted as a Fourier spectrum or a Laplace spectrum. The laws and functions of the method are discussed in comparison with the known transformations, and a sample application is shown.

Interpreting Recoil for Undergraduate Students

NASA Astrophysics Data System (ADS)

Elsayed, Tarek A.

2012-04-01

The phenomenon of recoil is usually explained to students in the context of Newton's third law. Typically, when a projectile is fired, the recoil of the launch mechanism is interpreted as a reaction to the ejection of the smaller projectile. The same phenomenon is also interpreted in the context of the conservation of linear momentum, which is closely related to Newton's third law. Since the actual microscopic causes of recoil differ from one problem to another, some students (and teachers) may not be satisfied with understanding recoil through the principles of conservation of linear momentum and Newton's third law. For these students, the origin of the recoil motion should be presented in more depth.

Recoverable information and emergent conservation laws in fracton stabilizer codes

NASA Astrophysics Data System (ADS)

Schmitz, A. T.; Ma, Han; Nandkishore, Rahul M.; Parameswaran, S. A.

2018-04-01

We introduce a new quantity that we term recoverable information, defined for stabilizer Hamiltonians. For such models, the recoverable information provides a measure of the topological information as well as a physical interpretation, which is complementary to topological entanglement entropy. We discuss three different ways to calculate the recoverable information and prove their equivalence. To demonstrate its utility, we compute recoverable information for fracton models using all three methods where appropriate. From the recoverable information, we deduce the existence of emergent Z2 Gauss-law-type constraints, which in turn imply emergent Z2 conservation laws for pointlike quasiparticle excitations of an underlying topologically ordered phase.

Local conservation laws in spin-\\frac{1}{2} XY chains with open boundary conditions

NASA Astrophysics Data System (ADS)

Fagotti, Maurizio

2016-06-01

We revisit the conserved quantities of the spin-\\frac{1}{2} XY model with open boundary conditions. In the absence of a transverse field, we find new families of local charges and show that half of the seeming conservation laws are conserved only if the number of sites is odd. In even chains the set of noninteracting charges is abelian, like in the periodic case when the number of sites is odd. In odd chains the set is doubled and becomes non-abelian, like in even periodic chains. The dependence of the charges on the parity of the chain’s size undermines the common belief that the thermodynamic limit of diagonal ensembles exists. We consider also the transverse-field Ising chain, where the situation is more ordinary. The generalization to the XY model in a transverse field is not straightforward and we propose a general framework to carry out similar calculations. We conjecture the form of the bulk part of the local charges and discuss the emergence of quasilocal conserved quantities. We provide evidence that in a region of the parameter space there is a reduction of the number of quasilocal conservation laws invariant under chain inversion. As a by-product, we study a class of block-Toeplitz-plus-Hankel operators and identify the conditions that their symbols satisfy in order to commute with a given block-Toeplitz.

INCINERATION OF SOLID WASTE

EPA Science Inventory

The concern over solid waste disposal and dump-site clean-up has resulted in the passage of three major U.S. environmental laws. They are the Resource Conservation and Recovery Act (RCRA) of 1976, Public Law 94-580, the Toxic Substances Control Act (TSCA) of 1976, Public Law 94-4...

Matter Scatter and Energy Anarchy. The Second Law of Thermodynamics is Simply Common Experience.

ERIC Educational Resources Information Center

Ross, Keith A.

1988-01-01

Shows that the second law of thermodynamics is in the common experience of many people and if taught first, before the law of conservation, can result in fewer misconceptions among pupils. Stresses the use of common experiences in teaching. (CW)

Discretely Conservative Finite-Difference Formulations for Nonlinear Conservation Laws in Split Form: Theory and Boundary Conditions

NASA Technical Reports Server (NTRS)

Fisher, Travis C.; Carpenter, Mark H.; Nordstroem, Jan; Yamaleev, Nail K.; Swanson, R. Charles

2011-01-01

Simulations of nonlinear conservation laws that admit discontinuous solutions are typically restricted to discretizations of equations that are explicitly written in divergence form. This restriction is, however, unnecessary. Herein, linear combinations of divergence and product rule forms that have been discretized using diagonal-norm skew-symmetric summation-by-parts (SBP) operators, are shown to satisfy the sufficient conditions of the Lax-Wendroff theorem and thus are appropriate for simulations of discontinuous physical phenomena. Furthermore, special treatments are not required at the points that are near physical boundaries (i.e., discrete conservation is achieved throughout the entire computational domain, including the boundaries). Examples are presented of a fourth-order, SBP finite-difference operator with second-order boundary closures. Sixth- and eighth-order constructions are derived, and included in E. Narrow-stencil difference operators for linear viscous terms are also derived; these guarantee the conservative form of the combined operator.

Residential energy conservation measures: a penny saved is a penny earned

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finklea, E.A.; Treiber, M.P.

The authors are not suggesting that conservation alone will end our dependence on foreign oil. The focus is on basic household energy-conservation measures because they are technically simple, inexpensive, and available compared to more advanced energy-efficiency technologies (e.g., architectural designs and passive solar devices), or to alternative production technologies (e.g., photovoltaics and synthetic fuels). The social, institutional, and economic obstacles to implementing these basic measures are analyzed, and suggestions offered for overcoming these obstacles. During the Carter Administration, Congress enacted four laws to encourage the installation of household energy conservation measures. The laws provide: (1) tax credits for energy conservationmore » expenditures; (2) conservation investment subsidies for low income homeowners; and require: (3) natural gas and electric utilities to implement residential energy conservation programs for their customers; and (4) the federal government to provide loan subsidies for household energy-conservation investments through a conservation bank. The potential effectiveness of these federal programs are analyzed. President Reagan's advisers have indicated that the new administration will place greater emphasis on energy production and less emphasis on conservation. Consequently, the effectiveness of these programs may depend on the priority given them by the Reagan administration.« less

50 CFR 679.3 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... fishing for groundfish. (1) The conservation and management of groundfish in waters of the territorial sea.... Additional regulations governing the conservation and management of halibut are set forth in subpart E of...

50 CFR 679.3 - Relation to other laws.

Code of Federal Regulations, 2011 CFR

2011-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... fishing for groundfish. (1) The conservation and management of groundfish in waters of the territorial sea.... Additional regulations governing the conservation and management of halibut are set forth in subpart E of...

ECP (Environmental Conservation Project) Report, No. 5, March 1976. Planning for Energy Conservation.

ERIC Educational Resources Information Center

Environmental Law Inst., Washington, DC.

The culmination of the Environmental Law Institute's Energy Conservation Project will be a series of handbooks addressed to state and local officials, legislators, and interested citizens setting out suggested strategies for conserving energy. This issue of the ECP Report publishes the first of a series of draft chapters from these handbooks - a…

78 FR 54685 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

76 FR 58049 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-19

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

75 FR 62892 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub .L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-13

... Conservation Act of 1978 (Pub .L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Modification Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

78 FR 52218 - Notice of permit applications received under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-22

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of permit applications received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

75 FR 62891 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-13

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

76 FR 52354 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-22

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

78 FR 9072 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-07

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

75 FR 54389 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-07

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Modification Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

75 FR 25300 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-07

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

76 FR 30397 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-25

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Modification Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

78 FR 58568 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-24

... Conservation Act of 1978 (Pub. L. 95-541) AGENCY: National Science Foundation. ACTION: Notice of Permit Applications Received under the Antarctic Conservation Act of 1978, Public Law 95-541. SUMMARY: The National... activities regulated under the Antarctic Conservation Act of 1978. NSF has published regulations under the...

Spiritual Assessment of Students at Conservative Wesleyan-Arminian Bible Colleges

ERIC Educational Resources Information Center

Cooley, Timothy L., Sr.

2011-01-01

The current study proposed to determine the level of spiritual transformation in students at conservative Wesleyan-Arminian Bible colleges and the association of spiritual transformation with selected Bible college activities. A quantitative survey was designed, validated, and implemented to measure students' self-reported levels of spiritual…

50 CFR 665.123 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Relation to other laws. 665.123 Section 665.123 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 665.123 Relation to other laws. To ensure consistency between the management regimes of different...

50 CFR 600.705 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Relation to other laws. 600.705 Section 600.705 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 600.705 Relation to other laws. (a) General. Persons affected by these regulations should be aware...

50 CFR 600.705 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Relation to other laws. 600.705 Section 600.705 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 600.705 Relation to other laws. (a) General. Persons affected by these regulations should be aware...

50 CFR 600.705 - Relation to other laws.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Relation to other laws. 600.705 Section 600.705 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 600.705 Relation to other laws. (a) General. Persons affected by these regulations should be aware...

50 CFR 600.705 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Relation to other laws. 600.705 Section 600.705 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... § 600.705 Relation to other laws. (a) General. Persons affected by these regulations should be aware...

U.S. nanotechnology policy and the decay of environmental law, 1980--2005

NASA Astrophysics Data System (ADS)

Rudd, Jeffrey D.

2009-11-01

Environmental law's authority to protect humans and the environment from pollution and resource exploitation began to deteriorate in the early 1980s. The dissertation is a modest attempt to answer the question, "What caused the gradual erosion in environmental law's normative authority?" It argues that the emergence of a neoliberal, market-centered ideology redefined the relationship between economic and environmental policies, causing environmental law's transformation into an instrument of economic discourse. This ethical transformation weakened environmental law's authority to protect humans and the environment from risks posed by unbridled economic growth policies. It also sparked the rise of an ideology to counter neoliberalism's power over environmental policy: sustainable development or "sustainability." Sustainable development reaffirms environmental law's normative authority and relies upon deliberative democratic principles similar to those that drove the enactment of environmental legislation during the 1960s and 1970s. The dissertation analyzes environmental law's transformation through two complementary case studies. First, it shows how the expansion of regulatory agencies' legislative power has combined with cost-benefit analysis mandates to undermine the goals of environmental law and limit democratic debate about environmental policy. Second, it analyzes the genesis and development of nanotechnology policy in the United States to show how neoliberalism's economic logic subtly erodes environmental law's normative authority. These case studies illuminate pragmatic differences in substance and process between neoliberalism and sustainable development. They also show that the relative balance of institutional authority over risk-related information determines the effectiveness and durability of legislative mandates intended to protect the environment.

Covariance of fluid-turbulence theory.

PubMed

Ariki, Taketo

2015-05-01

Covariance of physical quantities in fluid-turbulence theory and their governing equations under generalized coordinate transformation is discussed. It is shown that the velocity fluctuation and its governing law have a covariance under far wider group of coordinate transformation than that of conventional Euclidean invariance, and, as a natural consequence, various correlations and their governing laws are shown to be formulated in covariant manners under this wider transformation group. In addition, it is also shown that the covariance of the Reynolds stress is tightly connected to the objectivity of the mean flow.

Learning and the transformative potential of citizen science.

PubMed

Bela, Györgyi; Peltola, Taru; Young, Juliette C; Balázs, Bálint; Arpin, Isabelle; Pataki, György; Hauck, Jennifer; Kelemen, Eszter; Kopperoinen, Leena; Van Herzele, Ann; Keune, Hans; Hecker, Susanne; Suškevičs, Monika; Roy, Helen E; Itkonen, Pekka; Külvik, Mart; László, Miklós; Basnou, Corina; Pino, Joan; Bonn, Aletta

2016-10-01

The number of collaborative initiatives between scientists and volunteers (i.e., citizen science) is increasing across many research fields. The promise of societal transformation together with scientific breakthroughs contributes to the current popularity of citizen science (CS) in the policy domain. We examined the transformative capacity of citizen science in particular learning through environmental CS as conservation tool. We reviewed the CS and social-learning literature and examined 14 conservation projects across Europe that involved collaborative CS. We also developed a template that can be used to explore learning arrangements (i.e., learning events and materials) in CS projects and to explain how the desired outcomes can be achieved through CS learning. We found that recent studies aiming to define CS for analytical purposes often fail to improve the conceptual clarity of CS; CS programs may have transformative potential, especially for the development of individual skills, but such transformation is not necessarily occurring at the organizational and institutional levels; empirical evidence on simple learning outcomes, but the assertion of transformative effects of CS learning is often based on assumptions rather than empirical observation; and it is unanimous that learning in CS is considered important, but in practice it often goes unreported or unevaluated. In conclusion, we point to the need for reliable and transparent measurement of transformative effects for democratization of knowledge production. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

Asymptotic-induced numerical methods for conservation laws

NASA Technical Reports Server (NTRS)

Garbey, Marc; Scroggs, Jeffrey S.

1990-01-01

Asymptotic-induced methods are presented for the numerical solution of hyperbolic conservation laws with or without viscosity. The methods consist of multiple stages. The first stage is to obtain a first approximation by using a first-order method, such as the Godunov scheme. Subsequent stages of the method involve solving internal-layer problems identified by using techniques derived via asymptotics. Finally, a residual correction increases the accuracy of the scheme. The method is derived and justified with singular perturbation techniques.

Taxonomic and regional uncertainty in species-area relationships and the identification of richness hotspots

PubMed Central

Guilhaumon, François; Gimenez, Olivier; Gaston, Kevin J.; Mouillot, David

2008-01-01

Species-area relationships (SARs) are fundamental to the study of key and high-profile issues in conservation biology and are particularly widely used in establishing the broad patterns of biodiversity that underpin approaches to determining priority areas for biological conservation. Classically, the SAR has been argued in general to conform to a power-law relationship, and this form has been widely assumed in most applications in the field of conservation biology. Here, using nonlinear regressions within an information theoretical model selection framework, we included uncertainty regarding both model selection and parameter estimation in SAR modeling and conducted a global-scale analysis of the form of SARs for vascular plants and major vertebrate groups across 792 terrestrial ecoregions representing almost 97% of Earth's inhabited land. The results revealed a high level of uncertainty in model selection across biomes and taxa, and that the power-law model is clearly the most appropriate in only a minority of cases. Incorporating this uncertainty into a hotspots analysis using multimodel SARs led to the identification of a dramatically different set of global richness hotspots than when the power-law SAR was assumed. Our findings suggest that the results of analyses that assume a power-law model may be at severe odds with real ecological patterns, raising significant concerns for conservation priority-setting schemes and biogeographical studies. PMID:18832179

On the use of log-transformation vs. nonlinear regression for analyzing biological power laws.

PubMed

Xiao, Xiao; White, Ethan P; Hooten, Mevin B; Durham, Susan L

2011-10-01

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power laws using linear regression (LR) on log-transformed data has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations, we demonstrate that the error distribution determines which method performs better, with NLR better characterizing data with additive, homoscedastic, normal error and LR better characterizing data with multiplicative, heteroscedastic, lognormal error. Analysis of 471 biological power laws shows that both forms of error occur in nature. While previous analyses based on log-transformation appear to be generally valid, future analyses should choose methods based on a combination of biological plausibility and analysis of the error distribution. We provide detailed guidelines and associated computer code for doing so, including a model averaging approach for cases where the error structure is uncertain.

An In-Depth Tutorial on Constitutive Equations for Elastic Anisotropic Materials

NASA Technical Reports Server (NTRS)

Nemeth, Michael P.

2011-01-01

An in-depth tutorial on the constitutive equations for elastic, anisotropic materials is presented. Basic concepts are introduced that are used to characterize materials, and notions about how anisotropic material deform are presented. Hooke s law and the Duhamel-Neuman law for isotropic materials are presented and discussed. Then, the most general form of Hooke s law for elastic anisotropic materials is presented and symmetry requirements are given. A similar presentation is also given for the generalized Duhamel-Neuman law for elastic, anisotropic materials that includes thermal effects. Transformation equations for stress and strains are presented and the most general form of the transformation equations for the constitutive matrices are given. Then, specialized transformation equations are presented for dextral rotations about the coordinate axes. Next, concepts of material symmetry are introduced and criteria for material symmetries are presented. Additionally, engineering constants of fully anisotropic, elastic materials are derived from first principles and the specialized to several cases of practical importance.

77 FR 60477 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978

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7 CFR 1469.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

.... Soil quality means resource concerns and/or opportunities related to depletion of soil organic matter..., or Tribal law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district...

7 CFR 1469.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

.... Soil quality means resource concerns and/or opportunities related to depletion of soil organic matter..., or Tribal law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district...

7 CFR 1469.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

.... Soil quality means resource concerns and/or opportunities related to depletion of soil organic matter..., or Tribal law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district...

Shock induced phase transitions and current generation in ferroelectric ceramics

NASA Astrophysics Data System (ADS)

Agrawal, Vinamra; Bhattacharya, Kaushik

2017-06-01

Ferroelectric materials are used as ferroelectric generators to obtain pulsed power by subjecting them to a shock loading. The impact induces a phase transition and at high impact speeds, dielectric breakdown. Depending on the loading conditions and the electromechanical boundary conditions, the current or voltage profiles obtained vary. We explore the phenomenon of large deformation dynamic behavior and the associated electro-thermo-mechanical coupling of ferroelectric materials in adiabatic environments. Using conservation laws, Maxwell's equations and second law of thermodynamics, we obtain a set of governing equations for the material and the driving force acting on the propagating phase boundary. We also account for the possibility of surface charges on the phase boundary in case of dielectric breakdown which introduces contribution of curvature of the phase boundary in the equations. Next, the governing equations are used to solve a plate impact problem. The Helmholtz energy of the material is chosen be a combination of piecewise quadratic potential in polarization and thermo-elastic material capable of undergoing phase transformation. We obtain current profiles for short circuit boundary conditions along with strain, particle velocity and temperature maps. US AFOSR through Center of Excellence in High Rate Deformation of Heterogeneous Materials FA 9550-12-1-0091.

Multiparticle systems in κ -Poincaré inspired by (2 +1 )D gravity

NASA Astrophysics Data System (ADS)

Kowalski-Glikman, Jerzy; Rosati, Giacomo

2015-04-01

Inspired by a Chern-Simons description of 2 +1 -dimensional gravity coupled to point particles we propose a new Lagrangian of a multiparticle system living in κ -Minkowski/κ -Poincaré spacetime. We derive the dynamics of interacting particles with κ -momentum space, alternative to the one proposed in the "principle of relative locality" literature. The model that we obtain takes account of the nonlocal topological interactions between the particles, so that the effective multiparticle action is not a sum of their free actions. In this construction the locality of particle processes is naturally implemented, even for distant observers. In particular a particle process is characterized by a local deformed energy-momentum conservation law. The spacetime transformations are generated by total charges/generators for the composite particle system, and leave unaffected the locality of individual particle processes.

A numerical resolution study of high order essentially non-oscillatory schemes applied to incompressible flow

NASA Technical Reports Server (NTRS)

Weinan, E.; Shu, Chi-Wang

1994-01-01

High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth-order central differences through fast Fourier transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large scale features, such as the total circulation around the roll-up region, are adequately resolved.

A numerical resolution study of high order essentially non-oscillatory schemes applied to incompressible flow

NASA Technical Reports Server (NTRS)

Weinan, E.; Shu, Chi-Wang

1992-01-01

High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth order central differences through Fast Fourier Transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large-scale features, such as the total circulation around the roll-up region, are adequately resolved.

Exponential Boundary Observers for Pressurized Water Pipe

NASA Astrophysics Data System (ADS)

Hermine Som, Idellette Judith; Cocquempot, Vincent; Aitouche, Abdel

2015-11-01

This paper deals with state estimation on a pressurized water pipe modeled by nonlinear coupled distributed hyperbolic equations for non-conservative laws with three known boundary measures. Our objective is to estimate the fourth boundary variable, which will be useful for leakage detection. Two approaches are studied. Firstly, the distributed hyperbolic equations are discretized through a finite-difference scheme. By using the Lipschitz property of the nonlinear term and a Lyapunov function, the exponential stability of the estimation error is proven by solving Linear Matrix Inequalities (LMIs). Secondly, the distributed hyperbolic system is preserved for state estimation. After state transformations, a Luenberger-like PDE boundary observer based on backstepping mathematical tools is proposed. An exponential Lyapunov function is used to prove the stability of the resulted estimation error. The performance of the two observers are shown on a water pipe prototype simulated example.

Relativistic covariance of Ohm's law

NASA Astrophysics Data System (ADS)

Starke, R.; Schober, G. A. H.

2016-04-01

The derivation of Lorentz-covariant generalizations of Ohm's law has been a long-term issue in theoretical physics with deep implications for the study of relativistic effects in optical and atomic physics. In this article, we propose an alternative route to this problem, which is motivated by the tremendous progress in first-principles materials physics in general and ab initio electronic structure theory in particular. We start from the most general, Lorentz-covariant first-order response law, which is written in terms of the fundamental response tensor χμ ν relating induced four-currents to external four-potentials. By showing the equivalence of this description to Ohm's law, we prove the validity of Ohm's law in every inertial frame. We further use the universal relation between χμ ν and the microscopic conductivity tensor σkℓ to derive a fully relativistic transformation law for the latter, which includes all effects of anisotropy and relativistic retardation. In the special case of a constant, scalar conductivity, this transformation law can be used to rederive a standard textbook generalization of Ohm's law.

Interference and the Law of Energy Conservation

ERIC Educational Resources Information Center

Drosd, Robert; Minkin, Leonid; Shapovalov, Alexander S.

2014-01-01

Introductory physics textbooks consider interference to be a process of redistribution of energy from the wave sources in the surrounding space resulting in constructive and destructive interferences. As one can expect, the total energy flux is conserved. However, one case of apparent non-conservation energy attracts great attention. Imagine that…

Students' Misunderstandings about the Energy Conservation Principle: A General View to Studies in Literature

ERIC Educational Resources Information Center

Tatar, Erdal; Oktay, Munir

2007-01-01

This paper serves to review previously reported studies on students' misunderstandings about the energy conservation principle (the first law of thermodynamics). Generally, studies in literature highlighted students' misunderstandings about the energy conservation principle stem from preliminaries about energy concept in daily life. Since prior…

Introducing Conservation of Momentum

ERIC Educational Resources Information Center

Brunt, Marjorie; Brunt, Geoff

2013-01-01

The teaching of the principle of conservation of linear momentum is considered (ages 15 + ). From the principle, the momenta of two masses in an isolated system are considered. Sketch graphs of the momenta make Newton's laws appear obvious. Examples using different collision conditions are considered. Conservation of momentum is considered…

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Conserving Earth's Biodiversity. [CD-ROM and] Instructor's Manual.

ERIC Educational Resources Information Center

2000

This CD-ROM is designed as an interactive learning tool to support teaching in highly interdisciplinary fields such as conservation of biodiversity. Topics introduced in the software include the impact of humans on natural landscapes, threats to biodiversity, methods and theories of conservation biology, environmental laws, and relevant economic…

7 CFR 1467.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... State by annual tilling of the soil, including tilling by one-trip planters; or sugarcane planted and... or territorial law for the express purpose of developing and carrying out a local soil and water...,” “soil conservation district,” “soil and water conservation district,” “resource conservation district...

Conservation of Mechanical Energy Using Dry Ice Slider-Projectiles

ERIC Educational Resources Information Center

Gales, Jenna; Baker, Blane

2008-01-01

Energy concepts are fundamentally important for describing and analyzing systems ranging from subatomic particles to spiral galaxies. In general, students first encounter such concepts in introductory courses that typically focus on forms of energy, energy transfer, and conservation laws. Within these courses, conservation of mechanical energy is…

Fully electromagnetic nonlinear gyrokinetic equations for tokamak edge turbulence

NASA Astrophysics Data System (ADS)

Hahm, T. S.; Wang, Lu; Madsen, J.

2009-02-01

An energy conserving set of the fully electromagnetic nonlinear gyrokinetic Vlasov equation and Maxwell's equations, which is applicable to both L-mode turbulence with large amplitude and H-mode turbulence in the presence of high E ×B shear has been derived. The phase-space action variational Lie perturbation method ensures the preservation of the conservation laws of the underlying Vlasov-Maxwell system. Generalized ordering takes ρi≪ρθi˜LE˜Lp≪R [here ρi is the thermal ion Larmor radius and ρθi=B /(Bθρi)], as typically observed in the tokamak H-mode edge, with LE and Lp being the radial electric field and pressure gradient lengths. k⊥ρi˜1 is assumed for generality, and the relative fluctuation amplitudes eδϕ /Ti˜δB/B are kept up to the second order. Extending the electrostatic theory in the presence of high E ×B shear [Hahm, Phys. Plasmas 3, 4658 (1996)], contributions of electromagnetic fluctuations to the particle charge density and current are explicitly evaluated via pullback transformation from the gyrocenter distribution function in the gyrokinetic Maxwell's equation.

Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brizard, Alain J

Final Technical Report for U.S. Department of Energy Grant No. DE-FG02-09ER55005 Nonlinear FLR Effects in Reduced Fluid Models Alain J. Brizard, Saint Michael's College The above-mentioned DoE grant was used to support research activities by the PI during a sabbatical leave from Saint Michael's College in 2009. The major focus of the work was the role played by guiding-center and gyrocenter (linear and nonlinear) polarization and magnetization effects in understanding transport processes in turbulent magnetized plasmas. The theoretical tools used for this work include Lie-transform perturbation methods and Lagrangian (variational) methods developed by the PI in previous work. The presentmore » final technical report lists (I) the peer-reviewed publications that were written based on work funded by the Grant; (II) invited and contributed conference presentations during the period funded by the Grant; and (III) seminars presented during the period funded by the Grant. I. Peer-reviewed Publications A.J. Brizard and N. Tronko, 2011, Exact momentum conservation for the gyrokinetic Vlasov- Poisson equations, Physics of Plasmas 18 , 082307:1-14 [http://dx.doi.org/10.1063/1.3625554 ]. J. Decker, Y. Peysson, A.J. Brizard, and F.-X. Duthoit, 2010, Orbit-averaged guiding-center Fokker-Planck operator for numerical applications, Physics of Plasmas 17, 112513:1-12 [http://dx.doi.org/10.1063/1.3519514]. A.J. Brizard, 2010, Noether derivation of exact conservation laws for dissipationless reduced fluid models, Physics of Plasmas 17, 112503:1-8 [http://dx.doi.org/10.1063/1.3515303]. F.-X. Duthoit, A.J. Brizard, Y. Peysson, and J. Decker, 2010, Perturbation analysis of trapped particle dynamics in axisymmetric dipole geometry, Physics of Plasmas 17, 102903:1-9 [http://dx.doi.org/10.1063/1.3486554]. A.J. Brizard, 2010, Exact energy conservation laws for full and truncated nonlinear gyrokinetic equations, Physics of Plasmas 17, 042303:1-11 [http://dx.doi.org/10.1063/1.3374428]. A.J. Brizard, J. Decker, Y. Peysson, and F.-X. Duthoit, 2009, Orbit-averaged guiding-center Fokker-Planck operator, Physics of Plasmas 16, 102304:1-9[http://dx.doi.org/10.1063/1.3249627]. A.J. Brizard, 2009, Variational Principles for Reduced Plasma Physics, Journal of Physics: Conference Series 169, 012003 [http://dx.doi.org/10.1088/1742-6596/169/1/012003]. II. Invited and Contributed Conference Presentations A.J. Brizard and N. Tronko, Momentum conservation law for the gyrokinetic Vlasov-Poisson equations, 53rd Annual Meeting of the APS Division of Plasma Physics, Salt Lake City (Utah), November 14-18, 2011. A.J. Brizard, P.J. Morrison, C. Chandre, and E. Tassi, On the road to the Hamiltonian formulation of gyrokinetic theory, 52nd Annual Meeting of the APS Division of Plasma Physics, Chicago (Illinois), November 8-12, 2010. F.-X. Duthoit, A.J. Brizard, Y. Peysson, and J. Decker, Lie-transform perturbation analysis of trapped-particle dynamics in axisymmetric dipole geometry, 2010 International Sherwood Fusion Theory Conference, Seattle (Washington), April 19-21, 2010. N. Tronko and A.J. Brizard, Gyrokinetic momentum conservation law, 2010 International Sherwood Fusion Theory Conference, Seattle (Washington), April 19-21, 2010. C. Chandre and A.J. Brizard, Hamiltonian formulation of reduced Vlasov-Maxwell equations, 50th Annual Meeting of the APS Division of Plasma Physics, Dallas (Texas), November 17-21, 2008. A.J. Brizard, Nonlinear FLR effects in reduced fluid models, Invited Presentation at 11th Easter Plasma Meeting, Torino (Italy), April 15-17, 2009. III. Seminars Reduced Fokker-Planck operators for advanced plasma simulations, seminar given at CEA Cadarache (France), May 25, 2009. Ray phase-space methods in linear mode conversion, seminar given at CPT Luminy (France), April 1, 2009. Old and new methods in gyrokinetic theory, seminar given at CEA Cadarache (France), March 20, 2009. Hamiltonian theory of adiabatic motion of relativistic charged particles, seminar given at CPT Luminy (France), March 11, 2009. Noether method for fluids and plasmas, seminar given at CEA Cadarache (France), February 5, 2009. Nonlinear FLR effects in reduced fluid models, invited speaker at the Journee de la Dynamique Non Lineaire, Centre de Physique Theorique, CNRS Luminy (Marseille, France), June 3, 2008.« less

A priori error estimates for an hp-version of the discontinuous Galerkin method for hyperbolic conservation laws

NASA Technical Reports Server (NTRS)

Bey, Kim S.; Oden, J. Tinsley

1993-01-01

A priori error estimates are derived for hp-versions of the finite element method for discontinuous Galerkin approximations of a model class of linear, scalar, first-order hyperbolic conservation laws. These estimates are derived in a mesh dependent norm in which the coefficients depend upon both the local mesh size h(sub K) and a number p(sub k) which can be identified with the spectral order of the local approximations over each element.

A practical example aiding understanding momentum in 1D: the water gun experiment

NASA Astrophysics Data System (ADS)

MacLeod, Katarin

2007-09-01

The law of conservation of momentum is one that students often have difficulties understanding. This experiment allows students to use childhood toys to examine and calculate the muzzle velocity of their favourite water gun by using an air track, a spark timer or data logger and the law of conservation of momentum in a one-dimensional case, a modification of the standard ballistic pendulum laboratory experiment (1990 Physics 100 Lab Manual St Francis Xavier University).

Algebraic aspects of evolution partial differential equation arising in the study of constant elasticity of variance model from financial mathematics

NASA Astrophysics Data System (ADS)

Motsepa, Tanki; Aziz, Taha; Fatima, Aeeman; Khalique, Chaudry Masood

2018-03-01

The optimal investment-consumption problem under the constant elasticity of variance (CEV) model is investigated from the perspective of Lie group analysis. The Lie symmetry group of the evolution partial differential equation describing the CEV model is derived. The Lie point symmetries are then used to obtain an exact solution of the governing model satisfying a standard terminal condition. Finally, we construct conservation laws of the underlying equation using the general theorem on conservation laws.

Lenz's law in the kitchen

NASA Astrophysics Data System (ADS)

Dindorf, Wojciech

1999-05-01

A steel blade—a rather vital part of a mixer—has fallen behind a cupboard in my kitchen. The cupboard is heavy and quite permanently mounted between stove and fridge. Hopeless situation! Unless—you are an experimental physicist. This straightforward demonstration helps in appreciating the connection between Lenz's law and the law of conservation of energy.

10 CFR 490.7 - Relationship to other law.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false Relationship to other law. 490.7 Section 490.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.7 Relationship to other law. (a) Nothing in this part shall be construed to require or authorize sale of, or...

Alternative Fuels Data Center: Idle Reduction Laws and Incentives

Science.gov Websites

Conserve Fuel Printable Version Share this resource Send a link to Alternative Fuels Data Center : Idle Reduction Laws and Incentives to someone by E-mail Share Alternative Fuels Data Center: Idle Fuels Data Center: Idle Reduction Laws and Incentives on Digg Find More places to share Alternative

Traveling wave solutions and conservation laws for nonlinear evolution equation

NASA Astrophysics Data System (ADS)

Baleanu, Dumitru; Inc, Mustafa; Yusuf, Abdullahi; Aliyu, Aliyu Isa

2018-02-01

In this work, the Riccati-Bernoulli sub-ordinary differential equation and modified tanh-coth methods are used to reach soliton solutions of the nonlinear evolution equation. We acquire new types of traveling wave solutions for the governing equation. We show that the equation is nonlinear self-adjoint by obtaining suitable substitution. Therefore, we construct conservation laws for the equation using new conservation theorem. The obtained solutions in this work may be used to explain and understand the physical nature of the wave spreads in the most dispersive medium. The constraint condition for the existence of solitons is stated. Some three dimensional figures for some of the acquired results are illustrated.

7 CFR 656.1 - Purpose.

Code of Federal Regulations, 2012 CFR

2012-01-01

... of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF... ENCOUNTERED IN NRCS-ASSISTED PROGRAMS § 656.1 Purpose. This part prescribes Natural Resources Conservation... laws and appropriate executive orders for administering NRCS programs. ...

7 CFR 656.1 - Purpose.

Code of Federal Regulations, 2014 CFR

2014-01-01

... of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF... ENCOUNTERED IN NRCS-ASSISTED PROGRAMS § 656.1 Purpose. This part prescribes Natural Resources Conservation... laws and appropriate executive orders for administering NRCS programs. ...

7 CFR 656.1 - Purpose.

Code of Federal Regulations, 2011 CFR

2011-01-01

... of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF... ENCOUNTERED IN NRCS-ASSISTED PROGRAMS § 656.1 Purpose. This part prescribes Natural Resources Conservation... laws and appropriate executive orders for administering NRCS programs. ...

7 CFR 656.1 - Purpose.

Code of Federal Regulations, 2010 CFR

2010-01-01

... of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF... ENCOUNTERED IN NRCS-ASSISTED PROGRAMS § 656.1 Purpose. This part prescribes Natural Resources Conservation... laws and appropriate executive orders for administering NRCS programs. ...

7 CFR 656.1 - Purpose.

Code of Federal Regulations, 2013 CFR

2013-01-01

... of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF... ENCOUNTERED IN NRCS-ASSISTED PROGRAMS § 656.1 Purpose. This part prescribes Natural Resources Conservation... laws and appropriate executive orders for administering NRCS programs. ...

Conservation law for self-paced movements.

PubMed

Huh, Dongsung; Sejnowski, Terrence J

2016-08-02

Optimal control models of biological movements introduce external task factors to specify the pace of movements. Here, we present the dual to the principle of optimality based on a conserved quantity, called "drive," that represents the influence of internal motivation level on movement pace. Optimal control and drive conservation provide equivalent descriptions for the regularities observed within individual movements. For regularities across movements, drive conservation predicts a previously unidentified scaling law between the overall size and speed of various self-paced hand movements in the absence of any external tasks, which we confirmed with psychophysical experiments. Drive can be interpreted as a high-level control variable that sets the overall pace of movements and may be represented in the brain as the tonic levels of neuromodulators that control the level of internal motivation, thus providing insights into how internal states affect biological motor control.

Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

PubMed

Eads, David A; Biggins, Dean E

2015-08-01

Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. © 2015 Society for Conservation Biology.

A new rate law describing microbial respiration.

PubMed

Jin, Qusheng; Bethke, Craig M

2003-04-01

The rate of microbial respiration can be described by a rate law that gives the respiration rate as the product of a rate constant, biomass concentration, and three terms: one describing the kinetics of the electron-donating reaction, one for the kinetics of the electron-accepting reaction, and a thermodynamic term accounting for the energy available in the microbe's environment. The rate law, derived on the basis of chemiosmotic theory and nonlinear thermodynamics, is unique in that it accounts for both forward and reverse fluxes through the electron transport chain. Our analysis demonstrates how a microbe's respiration rate depends on the thermodynamic driving force, i.e., the net difference between the energy available from the environment and energy conserved as ATP. The rate laws commonly applied in microbiology, such as the Monod equation, are specific simplifications of the general law presented. The new rate law is significant because it affords the possibility of extrapolating in a rigorous manner from laboratory experiment to a broad range of natural conditions, including microbial growth where only limited energy is available. The rate law also provides a new explanation of threshold phenomena, which may reflect a thermodynamic equilibrium where the energy released by electron transfer balances that conserved by ADP phosphorylation.

Numerical simulation of conservation laws

NASA Technical Reports Server (NTRS)

Chang, Sin-Chung; To, Wai-Ming

1992-01-01

A new numerical framework for solving conservation laws is being developed. This new approach differs substantially from the well established methods, i.e., finite difference, finite volume, finite element and spectral methods, in both concept and methodology. The key features of the current scheme include: (1) direct discretization of the integral forms of conservation laws, (2) treating space and time on the same footing, (3) flux conservation in space and time, and (4) unified treatment of the convection and diffusion fluxes. The model equation considered in the initial study is the standard one dimensional unsteady constant-coefficient convection-diffusion equation. In a stability study, it is shown that the principal and spurious amplification factors of the current scheme, respectively, are structurally similar to those of the leapfrog/DuFort-Frankel scheme. As a result, the current scheme has no numerical diffusion in the special case of pure convection and is unconditionally stable in the special case of pure diffusion. Assuming smooth initial data, it will be shown theoretically and numerically that, by using an easily determined optimal time step, the accuracy of the current scheme may reach a level which is several orders of magnitude higher than that of the MacCormack scheme, with virtually identical operation count.

New scheme for color confinement and violation of the non-Abelian Bianchi identities

NASA Astrophysics Data System (ADS)

Suzuki, Tsuneo; Ishiguro, Katsuya; Bornyakov, Vitaly

2018-02-01

A new scheme for color confinement in QCD due to violation of the non-Abelian Bianchi identities is proposed. The violation of the non-Abelian Bianchi identities (VNABI) Jμ is equal to Abelian-like monopole currents kμ defined by the violation of the Abelian-like Bianchi identities. Although VNABI is an adjoint operator satisfying the covariant conservation law DμJμ=0 , it satisfies, at the same time, the Abelian-like conservation law ∂μJμ=0 . The Abelian-like conservation law ∂μJμ=0 is also gauge-covariant. There are N2-1 conserved magnetic charges in the case of color S U (N ). The charge of each component of VNABI is quantized à la Dirac. The color-invariant eigenvalues λμ of VNABI also satisfy the Abelian conservation law ∂μλμ=0 and the magnetic charges of the eigenvalues are also quantized à la Dirac. If the color invariant eigenvalues condense in the QCD vacuum, each color component of the non-Abelian electric field Ea is squeezed by the corresponding color component of the solenoidal current Jμa. Then only the color singlets alone can survive as a physical state and non-Abelian color confinement is realized. This confinement picture is completely new in comparison with the previously studied monopole confinement scenario based on an Abelian projection after some partial gauge-fixing, where Abelian neutral states can survive as physical. To check if the scenario is realized in nature, numerical studies are done in the framework of lattice field theory by adopting pure S U (2 ) gauge theory for simplicity. Considering Jμ(x )=kμ(x ) in the continuum formulation, we adopt an Abelian-like definition of a monopole following DeGrand-Toussaint as a lattice version of VNABI, since the Dirac quantization condition of the magnetic charge is satisfied on lattice partially. To reduce severe lattice artifacts, we introduce various techniques of smoothing the thermalized vacuum. Smooth gauge fixings such as the maximal center gauge (MCG), block-spin transformations of Abelian-like monopoles and extraction of physically important infrared long monopole loops are adopted. We also employ the tree-level tadpole improved gauge action of S U (2 ) gluodynamics. With these various improvements, we measure the density of lattice VNABI: ρ (a (β ),n )=∑ μ ,sn √{∑ a (kμa(sn))2 }/(4 √{3 }Vnb3) , where kμa(sn) is an n blocked monopole in the color direction a , n is the number of blocking steps, Vn=V /n4 (b =n a (β )) is the lattice volume (spacing) of the blocked lattice. Beautiful and convincing scaling behaviors are seen when we plot the density ρ (a (β ),n ) versus b =n a (β ). A single universal curve ρ (b ) is found from n =1 to n =12 , which suggests that ρ (a (β ),n ) is a function of b =n a (β ) alone. The universal curve seems independent of a gauge fixing procedure used to smooth the lattice vacuum since the scaling is obtained in all gauges adopted. The scaling, if it exists also for n →∞ , shows that the lattice definition of VNABI has the continuum limit and the new confinement scenario is realized.

Generalised relativistic Ohm's laws, extended gauge transformations, and magnetic linking

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pegoraro, F.

2015-11-15

Generalisations of the relativistic ideal Ohm's law are presented that include specific dynamical features of the current carrying particles in a plasma. Cases of interest for space and laboratory plasmas are identified where these generalisations allow for the definition of generalised electromagnetic fields that transform under a Lorentz boost in the same way as the real electromagnetic fields and that obey the same set of homogeneous Maxwell's equations.

On the Conservation and Convergence to Weak Solutions of Global Schemes

NASA Technical Reports Server (NTRS)

Carpenter, Mark H.; Gottlieb, David; Shu, Chi-Wang

2001-01-01

In this paper we discuss the issue of conservation and convergence to weak solutions of several global schemes, including the commonly used compact schemes and spectral collocation schemes, for solving hyperbolic conservation laws. It is shown that such schemes, if convergent boundedly almost everywhere, will converge to weak solutions. The results are extensions of the classical Lax-Wendroff theorem concerning conservative schemes.

Residual Distribution Schemes for Conservation Laws Via Adaptive Quadrature

NASA Technical Reports Server (NTRS)

Barth, Timothy; Abgrall, Remi; Biegel, Bryan (Technical Monitor)

2000-01-01

This paper considers a family of nonconservative numerical discretizations for conservation laws which retains the correct weak solution behavior in the limit of mesh refinement whenever sufficient order numerical quadrature is used. Our analysis of 2-D discretizations in nonconservative form follows the 1-D analysis of Hou and Le Floch. For a specific family of nonconservative discretizations, it is shown under mild assumptions that the error arising from non-conservation is strictly smaller than the discretization error in the scheme. In the limit of mesh refinement under the same assumptions, solutions are shown to satisfy an entropy inequality. Using results from this analysis, a variant of the "N" (Narrow) residual distribution scheme of van der Weide and Deconinck is developed for first-order systems of conservation laws. The modified form of the N-scheme supplants the usual exact single-state mean-value linearization of flux divergence, typically used for the Euler equations of gasdynamics, by an equivalent integral form on simplex interiors. This integral form is then numerically approximated using an adaptive quadrature procedure. This renders the scheme nonconservative in the sense described earlier so that correct weak solutions are still obtained in the limit of mesh refinement. Consequently, we then show that the modified form of the N-scheme can be easily applied to general (non-simplicial) element shapes and general systems of first-order conservation laws equipped with an entropy inequality where exact mean-value linearization of the flux divergence is not readily obtained, e.g. magnetohydrodynamics, the Euler equations with certain forms of chemistry, etc. Numerical examples of subsonic, transonic and supersonic flows containing discontinuities together with multi-level mesh refinement are provided to verify the analysis.

Darboux transformation of the coupled nonisospectral Gross-Pitaevskii system and its multi-component generalization

NASA Astrophysics Data System (ADS)

Xu, Tao; Chen, Yong

2018-04-01

In this paper, we extend the one-component Gross-Pitaevskii (GP) equation to the two-component coupled GP system including damping term, linear and parabolic density profiles. The Lax pair with nonisospectral parameter and infinitely-many conservation laws of this coupled GP system are presented. Actually, the Darboux transformation (DT) for this kind of nonautonomous system is essentially different from the autonomous case. Consequently, we construct the DT of the coupled GP equations, besides, nonautonomous multi-solitons, one-breather and the first-order rogue wave are also obtained. Various kinds of one-soliton solution are constructed, which include stationary one-soliton and nonautonomous one-soliton propagating along the negative (positive) direction of x-axis. The interaction of two solitons and two-soliton bound state are demonstrated respectively. We get the nonautonomous one-breather on a curved background and this background is completely controlled by the parameter β. Using a limiting process, the nonautonomous first-order rogue wave can be obtained. Furthermore, some dynamic structures of these analytical solutions are discussed in detail. In addition, the multi-component generalization of GP equations are given, then the corresponding Lax pair and DT are also constructed.

Piagetian conservation of discrete quantities in bonobos (Pan paniscus), chimpanzees (Pan troglodytes), and orangutans (Pongo pygmaeus).

PubMed

Suda, Chikako; Call, Josep

2005-10-01

This study investigated whether physical discreteness helps apes to understand the concept of Piagetian conservation (i.e. the invariance of quantities). Subjects were four bonobos, three chimpanzees, and five orangutans. Apes were tested on their ability to conserve discrete/continuous quantities in an over-conservation procedure in which two unequal quantities of edible rewards underwent various transformations in front of subjects. Subjects were examined to determine whether they could track the larger quantity of reward after the transformation. Comparison between the two types of conservation revealed that tests with bonobos supported the discreteness hypothesis. Bonobos, but neither chimpanzees nor orangutans, performed significantly better with discrete quantities than with continuous ones. The results suggest that at least bonobos could benefit from the discreteness of stimuli in their acquisition of conservation skills.

The Role of International Human Rights Norms in the Liberalization of Abortion Laws Globally.

PubMed

Fine, Johanna B; Mayall, Katherine; Sepúlveda, Lilian

2017-06-01

International and regional human rights norms have evolved significantly to recognize that the denial of abortion care in a range of circumstances violates women's and girls' fundamental human rights. These increasingly progressive standards have played a critical role in transforming national-level abortion laws by both influencing domestic high court decisions on abortion and serving as a critical resource in advancing law and policy reform. Courts in countries such as Argentina, Bolivia, Brazil, Colombia, and Nepal have directly incorporated these standards into groundbreaking cases liberalizing abortion laws and increasing women's access to safe abortion services, demonstrating the influence of these human rights standards in advancing women's reproductive freedom. These norms have also underpinned national-level abortion law and policy reform, including in countries such as Spain, Rwanda, Uruguay, and Peru. As these human rights norms further evolve and increasingly recognize abortion as a human rights imperative, these standards have the potential to bolster transformative jurisprudence and law and policy reform advancing women's and girls' full reproductive autonomy.

Finite Volume Methods: Foundation and Analysis

NASA Technical Reports Server (NTRS)

Barth, Timothy; Ohlberger, Mario

2003-01-01

Finite volume methods are a class of discretization schemes that have proven highly successful in approximating the solution of a wide variety of conservation law systems. They are extensively used in fluid mechanics, porous media flow, meteorology, electromagnetics, models of biological processes, semi-conductor device simulation and many other engineering areas governed by conservative systems that can be written in integral control volume form. This article reviews elements of the foundation and analysis of modern finite volume methods. The primary advantages of these methods are numerical robustness through the obtention of discrete maximum (minimum) principles, applicability on very general unstructured meshes, and the intrinsic local conservation properties of the resulting schemes. Throughout this article, specific attention is given to scalar nonlinear hyperbolic conservation laws and the development of high order accurate schemes for discretizing them. A key tool in the design and analysis of finite volume schemes suitable for non-oscillatory discontinuity capturing is discrete maximum principle analysis. A number of building blocks used in the development of numerical schemes possessing local discrete maximum principles are reviewed in one and several space dimensions, e.g. monotone fluxes, E-fluxes, TVD discretization, non-oscillatory reconstruction, slope limiters, positive coefficient schemes, etc. When available, theoretical results concerning a priori and a posteriori error estimates are given. Further advanced topics are then considered such as high order time integration, discretization of diffusion terms and the extension to systems of nonlinear conservation laws.

Renormalization group approach to power-law modeling of complex metabolic networks.

PubMed

Hernández-Bermejo, Benito

2010-08-07

In the modeling of complex biological systems, and especially in the framework of the description of metabolic pathways, the use of power-law models (such as S-systems and GMA systems) often provides a remarkable accuracy over several orders of magnitude in concentrations, an unusually broad range not fully understood at present. In order to provide additional insight in this sense, this article is devoted to the renormalization group analysis of reactions in fractal or self-similar media. In particular, the renormalization group methodology is applied to the investigation of how rate-laws describing such reactions are transformed when the geometric scale is changed. The precise purpose of such analysis is to investigate whether or not power-law rate-laws present some remarkable features accounting for the successes of power-law modeling. As we shall see, according to the renormalization group point of view the answer is positive, as far as power-laws are the critical solutions of the renormalization group transformation, namely power-law rate-laws are the renormalization group invariant solutions. Moreover, it is shown that these results also imply invariance under the group of concentration scalings, thus accounting for the reported power-law model accuracy over several orders of magnitude in metabolite concentrations. Copyright 2010 Elsevier Ltd. All rights reserved.

The Effectiveness of Problem-Based Learning on Teaching the First Law of Thermodynamics

ERIC Educational Resources Information Center

Tatar, Erdal; Oktay, Munir

2011-01-01

Background: Problem-based learning (PBL) is a teaching approach working in cooperation with self-learning and involving research to solve real problems. The first law of thermodynamics states that energy can neither be created nor destroyed, but that energy is conserved. Students had difficulty learning or misconceptions about this law. This study…

Impact of the Illinois Seat Belt Use Law on Accidents, Deaths, and Injuries.

ERIC Educational Resources Information Center

Rock, Steven M.

1992-01-01

The impact of the 1985 Illinois seat belt law is explored using Box-Jenkins Auto-Regressive, Integrated Moving Averages (ARIMA) techniques and monthly accident statistical data from the state department of transportation for January-July 1990. A conservative estimate is that the law provides benefits of $15 million per month in Illinois. (SLD)

Conservation of connectivity of model-space effective interactions under a class of similarity transformation.

PubMed

Duan, Chang-Kui; Gong, Yungui; Dong, Hui-Ning; Reid, Michael F

2004-09-15

Effective interaction operators usually act on a restricted model space and give the same energies (for Hamiltonian) and matrix elements (for transition operators, etc.) as those of the original operators between the corresponding true eigenstates. Various types of effective operators are possible. Those well defined effective operators have been shown to be related to each other by similarity transformation. Some of the effective operators have been shown to have connected-diagram expansions. It is shown in this paper that under a class of very general similarity transformations, the connectivity is conserved. The similarity transformation between Hermitian and non-Hermitian Rayleigh-Schrodinger perturbative effective operators is one of such transformations and hence the connectivity can be deducted from each other.

Spacecraft nonlinear control

NASA Technical Reports Server (NTRS)

Sheen, Jyh-Jong; Bishop, Robert H.

1992-01-01

The feedback linearization technique is applied to the problem of spacecraft attitude control and momentum management with control moment gyros (CMGs). The feedback linearization consists of a coordinate transformation, which transforms the system to a companion form, and a nonlinear feedback control law to cancel the nonlinear dynamics resulting in a linear equivalent model. Pole placement techniques are then used to place the closed-loop poles. The coordinate transformation proposed here evolves from three output functions of relative degree four, three, and two, respectively. The nonlinear feedback control law is presented. Stability in a neighborhood of a controllable torque equilibrium attitude (TEA) is guaranteed and this fact is demonstrated by the simulation results. An investigation of the nonlinear control law shows that singularities exist in the state space outside the neighborhood of the controllable TEA. The nonlinear control law is simplified by a standard linearization technique and it is shown that the linearized nonlinear controller provides a natural way to select control gains for the multiple-input, multiple-output system. Simulation results using the linearized nonlinear controller show good performance relative to the nonlinear controller in the neighborhood of the TEA.

On the use of log-transformation vs. nonlinear regression for analyzing biological power laws

USGS Publications Warehouse

Xiao, X.; White, E.P.; Hooten, M.B.; Durham, S.L.

2011-01-01

Power-law relationships are among the most well-studied functional relationships in biology. Recently the common practice of fitting power laws using linear regression (LR) on log-transformed data has been criticized, calling into question the conclusions of hundreds of studies. It has been suggested that nonlinear regression (NLR) is preferable, but no rigorous comparison of these two methods has been conducted. Using Monte Carlo simulations, we demonstrate that the error distribution determines which method performs better, with NLR better characterizing data with additive, homoscedastic, normal error and LR better characterizing data with multiplicative, heteroscedastic, lognormal error. Analysis of 471 biological power laws shows that both forms of error occur in nature. While previous analyses based on log-transformation appear to be generally valid, future analyses should choose methods based on a combination of biological plausibility and analysis of the error distribution. We provide detailed guidelines and associated computer code for doing so, including a model averaging approach for cases where the error structure is uncertain. ?? 2011 by the Ecological Society of America.

Menzerath-Altmann Law: Statistical Mechanical Interpretation as Applied to a Linguistic Organization

NASA Astrophysics Data System (ADS)

Eroglu, Sertac

2014-10-01

The distribution behavior described by the empirical Menzerath-Altmann law is frequently encountered during the self-organization of linguistic and non-linguistic natural organizations at various structural levels. This study presents a statistical mechanical derivation of the law based on the analogy between the classical particles of a statistical mechanical organization and the distinct words of a textual organization. The derived model, a transformed (generalized) form of the Menzerath-Altmann model, was termed as the statistical mechanical Menzerath-Altmann model. The derived model allows interpreting the model parameters in terms of physical concepts. We also propose that many organizations presenting the Menzerath-Altmann law behavior, whether linguistic or not, can be methodically examined by the transformed distribution model through the properly defined structure-dependent parameter and the energy associated states.

Phylogenetic distribution and evolutionary dynamics of the sex determination genes doublesex and transformer in insects.

PubMed

Geuverink, E; Beukeboom, L W

2014-01-01

Sex determination in insects is characterized by a gene cascade that is conserved at the bottom but contains diverse primary signals at the top. The bottom master switch gene doublesex is found in all insects. Its upstream regulator transformer is present in the orders Hymenoptera, Coleoptera and Diptera, but has thus far not been found in Lepidoptera and in the basal lineages of Diptera. transformer is presumed to be ancestral to the holometabolous insects based on its shared domains and conserved features of autoregulation and sex-specific splicing. We interpret that its absence in basal lineages of Diptera and its order-specific conserved domains indicate multiple independent losses or recruitments into the sex determination cascade. Duplications of transformer are found in derived families within the Hymenoptera, characterized by their complementary sex determination mechanism. As duplications are not found in any other insect order, they appear linked to the haplodiploid reproduction of the Hymenoptera. Further phylogenetic analyses combined with functional studies are needed to understand the evolutionary history of the transformer gene among insects. © 2013 S. Karger AG, Basel.

10 CFR 431.197 - Manufacturer's determination of efficiency for distribution transformers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... distribution transformers. 431.197 Section 431.197 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Compliance and Enforcement § 431.197 Manufacturer's determination of efficiency for distribution transformers. When a...

Physics That Textbook Writers Usually Get Wrong: II. Heat and Energy.

ERIC Educational Resources Information Center

Bauman, Robert P.

1992-01-01

Examines problems that occur with the vocabulary used in physics textbooks related to heat and energy. Discusses the concepts of thermal energy and temperature, conservation of energy laws, and the first law of thermodynamics. (MDH)

7 CFR 631.21 - Compliance with regulatory measures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 631.21 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES... the implementation and maintenance of the conservation practices in keeping with applicable laws and... others or from any failure to comply with applicable laws or regulations. ...

7 CFR 631.21 - Compliance with regulatory measures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 631.21 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES... the implementation and maintenance of the conservation practices in keeping with applicable laws and... others or from any failure to comply with applicable laws or regulations. ...

7 CFR 631.21 - Compliance with regulatory measures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 631.21 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES... the implementation and maintenance of the conservation practices in keeping with applicable laws and... others or from any failure to comply with applicable laws or regulations. ...

7 CFR 631.21 - Compliance with regulatory measures.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 631.21 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES... the implementation and maintenance of the conservation practices in keeping with applicable laws and... others or from any failure to comply with applicable laws or regulations. ...

7 CFR 631.21 - Compliance with regulatory measures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 631.21 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES... the implementation and maintenance of the conservation practices in keeping with applicable laws and... others or from any failure to comply with applicable laws or regulations. ...

Law School, University of Minnesota, Minneapolis

ERIC Educational Resources Information Center

American School and University, 1977

1977-01-01

The University of Minnesota Law School is a winner in the AS&U 1977 College & University Architectural Competition. The jury commented on the strong recognition of energy conservation and the skillful integration of the building with the existing campus. (Author/MLF)

Lie symmetry analysis, explicit solutions and conservation laws for the space-time fractional nonlinear evolution equations

NASA Astrophysics Data System (ADS)

Inc, Mustafa; Yusuf, Abdullahi; Aliyu, Aliyu Isa; Baleanu, Dumitru

2018-04-01

This paper studies the symmetry analysis, explicit solutions, convergence analysis, and conservation laws (Cls) for two different space-time fractional nonlinear evolution equations with Riemann-Liouville (RL) derivative. The governing equations are reduced to nonlinear ordinary differential equation (ODE) of fractional order using their Lie point symmetries. In the reduced equations, the derivative is in Erdelyi-Kober (EK) sense, power series technique is applied to derive an explicit solutions for the reduced fractional ODEs. The convergence of the obtained power series solutions is also presented. Moreover, the new conservation theorem and the generalization of the Noether operators are developed to construct the nonlocal Cls for the equations . Some interesting figures for the obtained explicit solutions are presented.

Scale-covariant theory of gravitation and astrophysical applications

NASA Technical Reports Server (NTRS)

Canuto, V.; Adams, P. J.; Hsieh, S.-H.; Tsiang, E.

1977-01-01

A scale-covariant theory of gravitation is presented which is characterized by a set of equations that are complete only after a choice of the scale function is made. Special attention is given to gauge conditions and units which allow gravitational phenomena to be described in atomic units. The generalized gravitational-field equations are derived by performing a direct scale transformation, by extending Riemannian geometry to Weyl geometry through the introduction of the notion of cotensors, and from a variation principle. Modified conservation laws are provided, a set of dynamical equations is obtained, and astrophysical consequences are considered. The theory is applied to examine certain homogeneous cosmological solutions, perihelion shifts, light deflections, secular variations of planetary orbital elements, stellar structure equations for a star in quasi-static equilibrium, and the past thermal history of earth. The possible relation of the scale-covariant theory to gauge field theories and their predictions of cosmological constants is discussed.

Theory of the Sea Ice Thickness Distribution

NASA Astrophysics Data System (ADS)

Toppaladoddi, Srikanth; Wettlaufer, J. S.

2015-10-01

We use concepts from statistical physics to transform the original evolution equation for the sea ice thickness distribution g (h ) from Thorndike et al. into a Fokker-Planck-like conservation law. The steady solution is g (h )=N (q )hqe-h /H, where q and H are expressible in terms of moments over the transition probabilities between thickness categories. The solution exhibits the functional form used in observational fits and shows that for h ≪1 , g (h ) is controlled by both thermodynamics and mechanics, whereas for h ≫1 only mechanics controls g (h ). Finally, we derive the underlying Langevin equation governing the dynamics of the ice thickness h , from which we predict the observed g (h ). The genericity of our approach provides a framework for studying the geophysical-scale structure of the ice pack using methods of broad relevance in statistical mechanics.

Theory of the Sea Ice Thickness Distribution.

PubMed

Toppaladoddi, Srikanth; Wettlaufer, J S

2015-10-02

We use concepts from statistical physics to transform the original evolution equation for the sea ice thickness distribution g(h) from Thorndike et al. into a Fokker-Planck-like conservation law. The steady solution is g(h)=N(q)h(q)e(-h/H), where q and H are expressible in terms of moments over the transition probabilities between thickness categories. The solution exhibits the functional form used in observational fits and shows that for h≪1, g(h) is controlled by both thermodynamics and mechanics, whereas for h≫1 only mechanics controls g(h). Finally, we derive the underlying Langevin equation governing the dynamics of the ice thickness h, from which we predict the observed g(h). The genericity of our approach provides a framework for studying the geophysical-scale structure of the ice pack using methods of broad relevance in statistical mechanics.

Dynamics and elastic interactions of the discrete multi-dark soliton solutions for the Kaup-Newell lattice equation

NASA Astrophysics Data System (ADS)

Liu, Nan; Wen, Xiao-Yong

2018-03-01

Under consideration in this paper is the Kaup-Newell (KN) lattice equation which is an integrable discretization of the KN equation. Infinitely, many conservation laws and discrete N-fold Darboux transformation (DT) for this system are constructed and established based on its Lax representation. Via the resulting N-fold DT, the discrete multi-dark soliton solutions in terms of determinants are derived from non-vanishing background. Propagation and elastic interaction structures of such solitons are shown graphically. Overtaking interaction phenomena between/among the two, three and four solitons are discussed. Numerical simulations are used to explore their dynamical behaviors of such multi-dark solitons. Numerical results show that their evolutions are stable against a small noise. Results in this paper might be helpful for understanding the propagation of nonlinear Alfvén waves in plasmas.

Fast sweeping methods for hyperbolic systems of conservation laws at steady state II

NASA Astrophysics Data System (ADS)

Engquist, Björn; Froese, Brittany D.; Tsai, Yen-Hsi Richard

2015-04-01

The idea of using fast sweeping methods for solving stationary systems of conservation laws has previously been proposed for efficiently computing solutions with sharp shocks. We further develop these methods to allow for a more challenging class of problems including problems with sonic points, shocks originating in the interior of the domain, rarefaction waves, and two-dimensional systems. We show that fast sweeping methods can produce higher-order accuracy. Computational results validate the claims of accuracy, sharp shock curves, and optimal computational efficiency.

Systems of conservation laws with third-order Hamiltonian structures

NASA Astrophysics Data System (ADS)

Ferapontov, Evgeny V.; Pavlov, Maxim V.; Vitolo, Raffaele F.

2018-06-01

We investigate n-component systems of conservation laws that possess third-order Hamiltonian structures of differential-geometric type. The classification of such systems is reduced to the projective classification of linear congruences of lines in P^{n+2} satisfying additional geometric constraints. Algebraically, the problem can be reformulated as follows: for a vector space W of dimension n+2, classify n-tuples of skew-symmetric 2-forms A^{α } \\in Λ^2(W) such that φ _{β γ }A^{β }\\wedge A^{γ }=0, for some non-degenerate symmetric φ.

Duality and symmetry lost in solid mechanics

NASA Astrophysics Data System (ADS)

Bui, Huy Duong

2008-01-01

Some conservation laws in Solids and Fracture Mechanics present a lack of symmetry between kinematic and dynamic variables. It is shown that Duality is the right tool to re-establish the symmetry between equations and variables and to provide conservation laws of the pure divergence type which provide true path independent integrals. The loss of symmetry of some energetic expressions is exploited to derive a new method for solving some inverse problems. In particular, the earthquake inverse problem is solved analytically. To cite this article: H.D. Bui, C. R. Mecanique 336 (2008).

ADER schemes for scalar non-linear hyperbolic conservation laws with source terms in three-space dimensions

NASA Astrophysics Data System (ADS)

Toro, E. F.; Titarev, V. A.

2005-01-01

In this paper we develop non-linear ADER schemes for time-dependent scalar linear and non-linear conservation laws in one-, two- and three-space dimensions. Numerical results of schemes of up to fifth order of accuracy in both time and space illustrate that the designed order of accuracy is achieved in all space dimensions for a fixed Courant number and essentially non-oscillatory results are obtained for solutions with discontinuities. We also present preliminary results for two-dimensional non-linear systems.

Carl Neumann versus Rudolf Clausius on the propagation of electrodynamic potentials

NASA Astrophysics Data System (ADS)

Archibald, Thomas

1986-09-01

In the late 1860's, German electromagnetic theorists employing W. Weber's velocity-dependent force law were forced to confront the issue of energy conservation. One attempt to formulate a conservation law for such forces was due to Carl Neumann, who introduced a model employing retarded potentials in 1868. Rudolf Clausius quickly pointed out certain problems with the physical interpretation of Neumann's mathematical formalism. The debate between the two men continued until the 1880's and illustrates the strictures facing mathematical approaches to physical problems during this prerelativistic, pre-Maxwellian period.

High order filtering methods for approximating hyperbolic systems of conservation laws

NASA Technical Reports Server (NTRS)

Lafon, F.; Osher, S.

1991-01-01

The essentially nonoscillatory (ENO) schemes, while potentially useful in the computation of discontinuous solutions of hyperbolic conservation-law systems, are computationally costly relative to simple central-difference methods. A filtering technique is presented which employs central differencing of arbitrarily high-order accuracy except where a local test detects the presence of spurious oscillations and calls upon the full ENO apparatus to remove them. A factor-of-three speedup is thus obtained over the full-ENO method for a wide range of problems, with high-order accuracy in regions of smooth flow.

The second laws of quantum thermodynamics.

PubMed

Brandão, Fernando; Horodecki, Michał; Ng, Nelly; Oppenheim, Jonathan; Wehner, Stephanie

2015-03-17

The second law of thermodynamics places constraints on state transformations. It applies to systems composed of many particles, however, we are seeing that one can formulate laws of thermodynamics when only a small number of particles are interacting with a heat bath. Is there a second law of thermodynamics in this regime? Here, we find that for processes which are approximately cyclic, the second law for microscopic systems takes on a different form compared to the macroscopic scale, imposing not just one constraint on state transformations, but an entire family of constraints. We find a family of free energies which generalize the traditional one, and show that they can never increase. The ordinary second law relates to one of these, with the remainder imposing additional constraints on thermodynamic transitions. We find three regimes which determine which family of second laws govern state transitions, depending on how cyclic the process is. In one regime one can cause an apparent violation of the usual second law, through a process of embezzling work from a large system which remains arbitrarily close to its original state. These second laws are relevant for small systems, and also apply to individual macroscopic systems interacting via long-range interactions. By making precise the definition of thermal operations, the laws of thermodynamics are unified in this framework, with the first law defining the class of operations, the zeroth law emerging as an equivalence relation between thermal states, and the remaining laws being monotonicity of our generalized free energies.

The second laws of quantum thermodynamics

PubMed Central

Brandão, Fernando; Horodecki, Michał; Ng, Nelly; Oppenheim, Jonathan; Wehner, Stephanie

2015-01-01

The second law of thermodynamics places constraints on state transformations. It applies to systems composed of many particles, however, we are seeing that one can formulate laws of thermodynamics when only a small number of particles are interacting with a heat bath. Is there a second law of thermodynamics in this regime? Here, we find that for processes which are approximately cyclic, the second law for microscopic systems takes on a different form compared to the macroscopic scale, imposing not just one constraint on state transformations, but an entire family of constraints. We find a family of free energies which generalize the traditional one, and show that they can never increase. The ordinary second law relates to one of these, with the remainder imposing additional constraints on thermodynamic transitions. We find three regimes which determine which family of second laws govern state transitions, depending on how cyclic the process is. In one regime one can cause an apparent violation of the usual second law, through a process of embezzling work from a large system which remains arbitrarily close to its original state. These second laws are relevant for small systems, and also apply to individual macroscopic systems interacting via long-range interactions. By making precise the definition of thermal operations, the laws of thermodynamics are unified in this framework, with the first law defining the class of operations, the zeroth law emerging as an equivalence relation between thermal states, and the remaining laws being monotonicity of our generalized free energies. PMID:25675476

A new network representation of the metabolism to detect chemical transformation modules.

PubMed

Sorokina, Maria; Medigue, Claudine; Vallenet, David

2015-11-14

Metabolism is generally modeled by directed networks where nodes represent reactions and/or metabolites. In order to explore metabolic pathway conservation and divergence among organisms, previous studies were based on graph alignment to find similar pathways. Few years ago, the concept of chemical transformation modules, also called reaction modules, was introduced and correspond to sequences of chemical transformations which are conserved in metabolism. We propose here a novel graph representation of the metabolic network where reactions sharing a same chemical transformation type are grouped in Reaction Molecular Signatures (RMS). RMS were automatically computed for all reactions and encode changes in atoms and bonds. A reaction network containing all available metabolic knowledge was then reduced by an aggregation of reaction nodes and edges to obtain a RMS network. Paths in this network were explored and a substantial number of conserved chemical transformation modules was detected. Furthermore, this graph-based formalism allows us to define several path scores reflecting different biological conservation meanings. These scores are significantly higher for paths corresponding to known metabolic pathways and were used conjointly to build association rules that should predict metabolic pathway types like biosynthesis or degradation. This representation of metabolism in a RMS network offers new insights to capture relevant metabolic contexts. Furthermore, along with genomic context methods, it should improve the detection of gene clusters corresponding to new metabolic pathways.

A System of Conservative Regridding for Ice-Atmosphere Coupling in a General Circulation Model (GCM)

NASA Technical Reports Server (NTRS)

Fischer, R.; Nowicki, S.; Kelley, M.; Schmidt, G. A.

2014-01-01

The method of elevation classes, in which the ice surface model is run at multiple elevations within each grid cell, has proven to be a useful way for a low-resolution atmosphere inside a general circulation model (GCM) to produce high-resolution downscaled surface mass balance fields for use in one-way studies coupling atmospheres and ice flow models. Past uses of elevation classes have failed to conserve mass and energy because the transformation used to regrid to the atmosphere was inconsistent with the transformation used to downscale to the ice model. This would cause problems for two-way coupling. A strategy that resolves this conservation issue has been designed and is presented here. The approach identifies three grids between which data must be regridded and five transformations between those grids required by a typical coupled atmosphere-ice flow model. This paper develops a theoretical framework for the problem and shows how each of these transformations may be achieved in a consistent, conservative manner. These transformations are implemented in Glint2, a library used to couple atmosphere models with ice models. Source code and documentation are available for download. Confounding real-world issues are discussed, including the use of projections for ice modeling, how to handle dynamically changing ice geometry, and modifications required for finite element ice models.

National Energy Conservation Policy Act. Public Law 95-619, 95th Congress.

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC.

This publication is the National Energy Conservation Policy Act (P.L. 95-619). The purposes of this act are to provide for the regulation of interstate commerce, to reduce the growth in demand for energy in the United States, and to conserve nonrenewable energy resources produced in this nation and elsewhere, without inhibiting beneficial economic…

Conservative discretization of the Landau collision integral

DOE PAGES

Hirvijoki, E.; Adams, M. F.

2017-03-28

Here we describe a density, momentum-, and energy-conserving discretization of the nonlinear Landau collision integral. The method is suitable for both the finite-element and discontinuous Galerkin methods and does not require structured meshes. The conservation laws for the discretization are proven algebraically and demonstrated numerically for an axially symmetric nonlinear relaxation problem using a finite-element implementation.

A review of conservation legislation in Nepal: Past progress and future needs

NASA Astrophysics Data System (ADS)

Heinen, Joel T.; Kattel, Bijaya

1992-11-01

Nepal is considered a leader among developing nations with regard to conservation legislation and programs; it was among the first Asian nations to develop national conservation legislation, sign CITES, and develop a national conservation strategy. We review the history of modern conservation law in Nepal from the Rana period (early 1950s) to the present. The early legislation focused mainly on strict preservation of areas and species; this phase culminated in the National Parks and Wildlife Conservation Act of 1973. Subsequent legislation has evolved more in the direction of an integrated, holistic approach to conservation and is beginning to incorporate the participation of local people; subsequent amendments to the 1973 act allowed greater rights to rural villagers, and the designation of conservation areas in addition to the more strictly defined protected areas (national parks, wildlife reserves, etc.). Our review of conservation legislation suggests that Nepal has had many successes to date; the country has a protected area system covering over 10% of its land area, and many target species are recovering in parks and reserves. There are also some causes of concern, including staff shortages, financial constraints within the Department of National Parks and Wildlife Conservation, and the fact that there is little legal infrastructure outside of protected areas to enforce conservation laws; further, some aspects of hunting regulations are in need of revision. Primary needs include a comprehensive review of these policies and a nationalized strategy to ameliorate the shortcomings.

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Test Procedures § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Test Procedures § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Test Procedures § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Test Procedures § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

10 CFR 431.193 - Test procedures for measuring energy consumption of distribution transformers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... distribution transformers. 431.193 Section 431.193 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN COMMERCIAL AND INDUSTRIAL EQUIPMENT Distribution Transformers Test Procedures § 431.193 Test procedures for measuring energy consumption of distribution transformers. The test...

Consequences of Symmetries on the Analysis and Construction of Turbulence Models

NASA Astrophysics Data System (ADS)

Razafindralandy, Dina; Hamdouni, Aziz

2006-05-01

Since they represent fundamental physical properties in turbulence (conservation laws, wall laws, Kolmogorov energy spectrum, ...), symmetries are used to analyse common turbulence models. A class of symmetry preserving turbulence models is proposed. This class is refined such that the models respect the second law of thermodynamics. Finally, an example of model belonging to the class is numerically tested.

A New Rate Law Describing Microbial Respiration

PubMed Central

Jin, Qusheng; Bethke, Craig M.

2003-01-01

The rate of microbial respiration can be described by a rate law that gives the respiration rate as the product of a rate constant, biomass concentration, and three terms: one describing the kinetics of the electron-donating reaction, one for the kinetics of the electron-accepting reaction, and a thermodynamic term accounting for the energy available in the microbe's environment. The rate law, derived on the basis of chemiosmotic theory and nonlinear thermodynamics, is unique in that it accounts for both forward and reverse fluxes through the electron transport chain. Our analysis demonstrates how a microbe's respiration rate depends on the thermodynamic driving force, i.e., the net difference between the energy available from the environment and energy conserved as ATP. The rate laws commonly applied in microbiology, such as the Monod equation, are specific simplifications of the general law presented. The new rate law is significant because it affords the possibility of extrapolating in a rigorous manner from laboratory experiment to a broad range of natural conditions, including microbial growth where only limited energy is available. The rate law also provides a new explanation of threshold phenomena, which may reflect a thermodynamic equilibrium where the energy released by electron transfer balances that conserved by ADP phosphorylation. PMID:12676718

International and European law on protected areas and climate change: need for adaptation or implementation?

PubMed

Cliquet, A

2014-10-01

The protection and management of protected areas must be adapted to the effects of climate change. An important question is if the law on protected areas is capable of dealing with the required changes. In general, both international nature conventions and European Union nature conservation law do not contain any specific provisions on climate change and protected areas. Attention has been paid to this link in non-binding decisions and policy documents. In order to adapt the law to increased dynamics from climate change, more flexibility is needed. This flexibility should not be understood as "legal" flexibility, in the sense of the weakening nature conservation provisions. Scientific uncertainties on the effects of climate change might conflict with the need for legal certainties. In order to adapt to the effects of climate change, the two crucial elements are the strengthening of core protected areas and connectivity between the core areas. At the international level, both elements can be found in non-binding documents. International law enables the required adaptation; however, it often lacks concrete obligations. A stronger legal framework can be found at the level of the European Union. The Birds and Habitats Directives contain sufficient tools to deal with the effects of climate change. The Directives have been insufficiently implemented so far. Especially the central goals of reaching a favorable conservation status and connectivity measures need to be addressed much more in the future.

Modelling of Strains During SAW Surfacing Taking into Heat of the Weld in Temperature Field Description and Phase Transformations

NASA Astrophysics Data System (ADS)

Winczek, J.; Makles, K.; Gucwa, M.; Gnatowska, R.; Hatala, M.

2017-08-01

In the paper, the model of the thermal and structural strain calculation in a steel element during single-pass SAW surfacing is presented. The temperature field is described analytically assuming a bimodal volumetric model of heat source and a semi-infinite body model of the surfaced (rebuilt) workpiece. The electric arc is treated physically as one heat source. Part of the heat is transferred by the direct impact of the electric arc, while another part of the heat is transferred to the weld by the melted material of the electrode. Kinetics of phase transformations during heating is limited by temperature values at the beginning and at the end of austenitic transformation, while the progress of phase transformations during cooling is determined on the basis of TTT-welding diagramand JMA-K law for diffusive transformations, and K-M law for martensitic transformation. Totalstrains equal to the sum ofthermaland structuralstrainsinduced by phasetransformationsin weldingcycle.

Heat Transfer Analysis for Stationary Boundary Layer Slip Flow of a Power-Law Fluid in a Darcy Porous Medium with Plate Suction/Injection

PubMed Central

Aziz, Asim; Ali, Yasir; Aziz, Taha; Siddique, J. I.

2015-01-01

In this paper, we investigate the slip effects on the boundary layer flow and heat transfer characteristics of a power-law fluid past a porous flat plate embedded in the Darcy type porous medium. The nonlinear coupled system of partial differential equations governing the flow and heat transfer of a power-law fluid is transformed into a system of nonlinear coupled ordinary differential equations by applying a suitable similarity transformation. The resulting system of ordinary differential equations is solved numerically using Matlab bvp4c solver. Numerical results are presented in the form of graphs and the effects of the power-law index, velocity and thermal slip parameters, permeability parameter, suction/injection parameter on the velocity and temperature profiles are examined. PMID:26407162

40 CFR 256.30 - Requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... law from entering into long-term contracts for the supply of solid waste to resource recovery... AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Resource Conservation and Resource Recovery... resource conservation and recovery, the State plan shall provide for a policy and strategy for...

40 CFR 256.30 - Requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... law from entering into long-term contracts for the supply of solid waste to resource recovery... AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Resource Conservation and Resource Recovery... resource conservation and recovery, the State plan shall provide for a policy and strategy for...

40 CFR 256.30 - Requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... law from entering into long-term contracts for the supply of solid waste to resource recovery... AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Resource Conservation and Resource Recovery... resource conservation and recovery, the State plan shall provide for a policy and strategy for...

40 CFR 256.30 - Requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... law from entering into long-term contracts for the supply of solid waste to resource recovery... AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Resource Conservation and Resource Recovery... resource conservation and recovery, the State plan shall provide for a policy and strategy for...

40 CFR 256.30 - Requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... law from entering into long-term contracts for the supply of solid waste to resource recovery... AND IMPLEMENTATION OF STATE SOLID WASTE MANAGEMENT PLANS Resource Conservation and Resource Recovery... resource conservation and recovery, the State plan shall provide for a policy and strategy for...

Conservation Laws in Weak Interactions

DOE R&D Accomplishments Database

Lee, T. D.

1957-03-01

Notes are presented on four lectures given at Harvard University in March 1957 on elementary particle physics, the theta-tau problem, validity of parity conservation, tests for invariance under P, C, and T, and the two-component theory of the neutrino. (W.D.M.)

Steady at the wheel: conservative sex and the benefits of bacterial transformation

PubMed Central

Ambur, Ole Herman; Engelstädter, Jan; Johnsen, Pål J.

2016-01-01

Many bacteria are highly sexual, but the reasons for their promiscuity remain obscure. Did bacterial sex evolve to maximize diversity and facilitate adaptation in a changing world, or does it instead help to retain the bacterial functions that work right now? In other words, is bacterial sex innovative or conservative? Our aim in this review is to integrate experimental, bioinformatic and theoretical studies to critically evaluate these alternatives, with a main focus on natural genetic transformation, the bacterial equivalent of eukaryotic sexual reproduction. First, we provide a general overview of several hypotheses that have been put forward to explain the evolution of transformation. Next, we synthesize a large body of evidence highlighting the numerous passive and active barriers to transformation that have evolved to protect bacteria from foreign DNA, thereby increasing the likelihood that transformation takes place among clonemates. Our critical review of the existing literature provides support for the view that bacterial transformation is maintained as a means of genomic conservation that provides direct benefits to both individual bacterial cells and to transformable bacterial populations. We examine the generality of this view across bacteria and contrast this explanation with the different evolutionary roles proposed to maintain sex in eukaryotes.  This article is part of the themed issue ‘Weird sex: the underappreciated diversity of sexual reproduction’. PMID:27619692

Steady at the wheel: conservative sex and the benefits of bacterial transformation.

PubMed

Ambur, Ole Herman; Engelstädter, Jan; Johnsen, Pål J; Miller, Eric L; Rozen, Daniel E

2016-10-19

Many bacteria are highly sexual, but the reasons for their promiscuity remain obscure. Did bacterial sex evolve to maximize diversity and facilitate adaptation in a changing world, or does it instead help to retain the bacterial functions that work right now? In other words, is bacterial sex innovative or conservative? Our aim in this review is to integrate experimental, bioinformatic and theoretical studies to critically evaluate these alternatives, with a main focus on natural genetic transformation, the bacterial equivalent of eukaryotic sexual reproduction. First, we provide a general overview of several hypotheses that have been put forward to explain the evolution of transformation. Next, we synthesize a large body of evidence highlighting the numerous passive and active barriers to transformation that have evolved to protect bacteria from foreign DNA, thereby increasing the likelihood that transformation takes place among clonemates. Our critical review of the existing literature provides support for the view that bacterial transformation is maintained as a means of genomic conservation that provides direct benefits to both individual bacterial cells and to transformable bacterial populations. We examine the generality of this view across bacteria and contrast this explanation with the different evolutionary roles proposed to maintain sex in eukaryotes. This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. © 2016 The Author(s).

An HP Adaptive Discontinuous Galerkin Method for Hyperbolic Conservation Laws. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Bey, Kim S.

1994-01-01

This dissertation addresses various issues for model classes of hyperbolic conservation laws. The basic approach developed in this work employs a new family of adaptive, hp-version, finite element methods based on a special discontinuous Galerkin formulation for hyperbolic problems. The discontinuous Galerkin formulation admits high-order local approximations on domains of quite general geometry, while providing a natural framework for finite element approximations and for theoretical developments. The use of hp-versions of the finite element method makes possible exponentially convergent schemes with very high accuracies in certain cases; the use of adaptive hp-schemes allows h-refinement in regions of low regularity and p-enrichment to deliver high accuracy, while keeping problem sizes manageable and dramatically smaller than many conventional approaches. The use of discontinuous Galerkin methods is uncommon in applications, but the methods rest on a reasonable mathematical basis for low-order cases and has local approximation features that can be exploited to produce very efficient schemes, especially in a parallel, multiprocessor environment. The place of this work is to first and primarily focus on a model class of linear hyperbolic conservation laws for which concrete mathematical results, methodologies, error estimates, convergence criteria, and parallel adaptive strategies can be developed, and to then briefly explore some extensions to more general cases. Next, we provide preliminaries to the study and a review of some aspects of the theory of hyperbolic conservation laws. We also provide a review of relevant literature on this subject and on the numerical analysis of these types of problems.

Thermodynamics of third-order Lovelock-AdS black holes in the presence of Born-Infeld type nonlinear electrodynamics

NASA Astrophysics Data System (ADS)

Hendi, S. H.; Dehghani, A.

2015-03-01

In this paper, we obtain topological black hole solutions of third-order Lovelock gravity coupled with two classes of Born-Infeld-type nonlinear electrodynamics with anti-de Sitter asymptotic structure. We investigate geometric and thermodynamics properties of the solutions and obtain conserved quantities of the black holes. We examine the first law of thermodynamics and find that the conserved and thermodynamic quantities of the black hole solutions satisfy the first law of thermodynamics. Finally, we calculate the heat capacity and determinant of the Hessian matrix to evaluate thermal stability in both canonical and grand canonical ensembles. Moreover, we consider the extended phase space thermodynamics to obtain a generalized first law of thermodynamics as well as the extended Smarr formula.

Regularized Chapman-Enskog expansion for scalar conservation laws

NASA Technical Reports Server (NTRS)

Schochet, Steven; Tadmor, Eitan

1990-01-01

Rosenau has recently proposed a regularized version of the Chapman-Enskog expansion of hydrodynamics. This regularized expansion resembles the usual Navier-Stokes viscosity terms at law wave-numbers, but unlike the latter, it has the advantage of being a bounded macroscopic approximation to the linearized collision operator. The behavior of Rosenau regularization of the Chapman-Enskog expansion (RCE) is studied in the context of scalar conservation laws. It is shown that thie RCE model retains the essential properties of the usual viscosity approximation, e.g., existence of traveling waves, monotonicity, upper-Lipschitz continuity..., and at the same time, it sharpens the standard viscous shock layers. It is proved that the regularized RCE approximation converges to the underlying inviscid entropy solution as its mean-free-path epsilon approaches 0, and the convergence rate is estimated.

Transforming Symbolic Law into Organizational Action: Hate Crime Policy and Law Enforcement Practice

ERIC Educational Resources Information Center

Grattet, Ryken; Jenness, Valerie

2008-01-01

For decades sociologists, criminologists, political scientists and socio-legal scholars alike have focused on the symbolic and instrumental dimensions of law in examinations of the effects of social reform and policy implementation. Following in this tradition, we focus on the relationship between hate crime policy and hate crime reporting to…

The Role of International Human Rights Norms in the Liberalization of Abortion Laws Globally

PubMed Central

Fine, Johanna B.; Mayall, Katherine; Sepúlveda, Lilian

2017-01-01

Abstract International and regional human rights norms have evolved significantly to recognize that the denial of abortion care in a range of circumstances violates women’s and girls’ fundamental human rights. These increasingly progressive standards have played a critical role in transforming national-level abortion laws by both influencing domestic high court decisions on abortion and serving as a critical resource in advancing law and policy reform. Courts in countries such as Argentina, Bolivia, Brazil, Colombia, and Nepal have directly incorporated these standards into groundbreaking cases liberalizing abortion laws and increasing women’s access to safe abortion services, demonstrating the influence of these human rights standards in advancing women’s reproductive freedom. These norms have also underpinned national-level abortion law and policy reform, including in countries such as Spain, Rwanda, Uruguay, and Peru. As these human rights norms further evolve and increasingly recognize abortion as a human rights imperative, these standards have the potential to bolster transformative jurisprudence and law and policy reform advancing women’s and girls’ full reproductive autonomy. PMID:28630542

Synthetic biology and conservation of nature: wicked problems and wicked solutions.

PubMed

Redford, Kent H; Adams, William; Mace, Georgina M

2013-01-01

So far, conservation scientists have paid little attention to synthetic biology; this is unfortunate as the technology is likely to transform the operating space within which conservation functions, and therefore the prospects for maintaining biodiversity into the future.

Issues and challenges of mangrove conservation in the Anthropocene - Desafios de la conservacion del mangle en el Antropoceno

Treesearch

Ariel. E. Lugo; Ernesto Medina; Kathleen McGinley

2014-01-01

This essay addresses the conservation issues facing mangroves in the Anthropocene, defined as the era of human domination over the world. We review the laws, policies, international agreements, and local actions that address the conservation of mangrove forests in the Neotropics and relate them to the Anthropocene. Collaboration between governments, non-governmental...

Advances in Energy Conservation of China Steel Industry

PubMed Central

Sun, Wenqiang; Cai, Jiuju; Ye, Zhu

2013-01-01

The course, technical progresses, and achievements of energy conservation of China steel industry (CSI) during 1980–2010 were summarized. Then, the paper adopted e-p method to analyze the variation law and influencing factors of energy consumptions of large- and medium-scale steel plants within different stages. It is pointed out that energy consumption per ton of crude steel has been almost one half lower in these thirty years, with 60% as direct energy conservation owing to the change of process energy consumption and 40% as indirect energy conservation attributed to the adjustment of production structure. Next, the latest research progress of some key common technologies in CSI was introduced. Also, the downtrend of energy consumption per ton of crude steel and the potential energy conservation for CSI during 2011–2025 were forecasted. Finally, it is indicated that the key topic of the next 15 years' research on the energy conservation of CSI is the synergistic operation of material flow and energy flow. It could be achieved by the comprehensive study on energy flow network optimization, such as production, allocation, utilization, recovery, reuse, and resource, according to the energy quantity, quality, and user demand following the first and second laws of thermodynamics. PMID:23533344

Advances in energy conservation of China steel industry.

PubMed

Sun, Wenqiang; Cai, Jiuju; Ye, Zhu

2013-01-01

The course, technical progresses, and achievements of energy conservation of China steel industry (CSI) during 1980-2010 were summarized. Then, the paper adopted e-p method to analyze the variation law and influencing factors of energy consumptions of large- and medium-scale steel plants within different stages. It is pointed out that energy consumption per ton of crude steel has been almost one half lower in these thirty years, with 60% as direct energy conservation owing to the change of process energy consumption and 40% as indirect energy conservation attributed to the adjustment of production structure. Next, the latest research progress of some key common technologies in CSI was introduced. Also, the downtrend of energy consumption per ton of crude steel and the potential energy conservation for CSI during 2011-2025 were forecasted. Finally, it is indicated that the key topic of the next 15 years' research on the energy conservation of CSI is the synergistic operation of material flow and energy flow. It could be achieved by the comprehensive study on energy flow network optimization, such as production, allocation, utilization, recovery, reuse, and resource, according to the energy quantity, quality, and user demand following the first and second laws of thermodynamics.

Steam stripping of the unsaturated zone of contaminated sub-soils: The effect of diffusion/dispersion in the start-up phase

NASA Astrophysics Data System (ADS)

Brouwers, H. J. H.; Gilding, B. H.

2006-02-01

The unsteady process of steam stripping of the unsaturated zone of soils contaminated with volatile organic compounds (VOCs) is addressed. A model is presented. It accounts for the effects of water and contaminants remaining in vapour phase, as well as diffusion and dispersion of contaminants in this phase. The model has two components. The first is a one-dimensional description of the propagation of a steam front in the start-up phase. This is based on Darcy's law and conservation laws of mass and energy. The second component describes the transport of volatile contaminants. Taking the view that non-equilibrium between liquid and vapour phases exists, it accounts for evaporation, transport, and condensation at the front. This leads to a moving-boundary problem. The moving-boundary problem is brought into a fixed domain by a suitable transformation of the governing partial differential equations, and solved numerically. For a broad range of the governing dimensionless numbers, such as the Henry, Merkel and Péclet numbers, computational results are discussed. A mathematical asymptotic analysis supports this discussion. The range of parameter values for which the model is valid is investigated. Diffusion and dispersion are shown to be of qualitative importance, but to have little quantitative effect in the start-up phase.

7 CFR 633.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... organized pursuant to applicable State law to promote and undertake actions for the conservation of soil... the United States Department of Agriculture, formerly called the Soil Conservation Service. Operator... and improvement of water quality; (3) Attenuation of water flows due to flooding; (4) The recharge of...

7 CFR 633.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... organized pursuant to applicable State law to promote and undertake actions for the conservation of soil... the United States Department of Agriculture, formerly called the Soil Conservation Service. Operator... and improvement of water quality; (3) Attenuation of water flows due to flooding; (4) The recharge of...

Introducing Environmental Law in the Undergraduate Curriculum.

ERIC Educational Resources Information Center

Centner, Terence J.; Geyer, L. Leon

1993-01-01

Discusses the development of an undergraduate environmental law course. Initial considerations in course development include the instruction unit, student needs, choice of instructor, and text. Presents materials covered under categories of pollution prevention, conservation and sustainable systems, land use and local government, and cleanup and…

Learning Physics in a Water Park

ERIC Educational Resources Information Center

Cabeza, Cecilia; Rubido, Nicolás; Martí, Arturo C.

2014-01-01

Entertaining and educational experiments that can be conducted in a water park, illustrating physics concepts, principles and fundamental laws, are described. These experiments are suitable for students ranging from senior secondary school to junior university level. Newton's laws of motion, Bernoulli's equation, based on the conservation of…

Application of Hamilton's Law of Varying Action

NASA Technical Reports Server (NTRS)

Bailey, C. D.

1973-01-01

The application of Hamilton's Law to the direct solution of nonstationary as well as stationary problems in mechanics of solids is discussed. Solutions are demonstrated for conservative and monconservative, stationary and/or nonstationary particle motion. Mathematical models are developed to establish the relationships of the parameters.

Test of Von Baer's law of the conservation of early development.

PubMed

Poe, Steven

2006-11-01

One of the oldest and most pervasive ideas in comparative embryology is the perceived evolutionary conservation of early ontogeny relative to late ontogeny. Karl Von Baer first noted the similarity of early ontogeny across taxa, and Ernst Haeckel and Charles Darwin gave evolutionary interpretation to this phenomenon. In spite of a resurgence of interest in comparative embryology and the development of mechanistic explanations for Von Baer's law, the pattern itself has been largely untested. Here, I use statistical phylogenetic approaches to show that Von Baer's law is an unnecessarily complex explanation of the patterns of ontogenetic timing in several clades of vertebrates. Von Baer's law suggests a positive correlation between ontogenetic time and amount of evolutionary change. I compare ranked position in ontogeny to frequency of evolutionary change in rank for developmental events and find that these measures are not correlated, thus failing to support Von Baer's model. An alternative model that postulates that small changes in ontogenetic rank are evolutionarily easier than large changes is tentatively supported.

Definition of (so MIScalled) ''Complexity'' as UTTER-SIMPLICITY!!! Versus Deviations From it as Complicatedness-Measure

NASA Astrophysics Data System (ADS)

Young, F.; Siegel, Edward Carl-Ludwig

2011-03-01

(so MIScalled) "complexity" with INHERENT BOTH SCALE-Invariance Symmetry-RESTORING, AND 1 / w (1.000..) "pink" Zipf-law Archimedes-HYPERBOLICITY INEVITABILITY power-spectrum power-law decay algebraicity. Their CONNECTION is via simple-calculus SCALE-Invariance Symmetry-RESTORING logarithm-function derivative: (d/ d ω) ln(ω) = 1 / ω , i.e. (d/ d ω) [SCALE-Invariance Symmetry-RESTORING](ω) = 1/ ω . Via Noether-theorem continuous-symmetries relation to conservation-laws: (d/ d ω) [inter-scale 4-current 4-div-ergence} = 0](ω) = 1 / ω . Hence (so MIScalled) "complexity" is information inter-scale conservation, in agreement with Anderson-Mandell [Fractals of Brain/Mind, G. Stamov ed.(1994)] experimental-psychology!!!], i.e. (so MIScalled) "complexity" is UTTER-SIMPLICITY!!! Versus COMPLICATEDNESS either PLUS (Additive) VS. TIMES (Multiplicative) COMPLICATIONS of various system-specifics. COMPLICATEDNESS-MEASURE DEVIATIONS FROM complexity's UTTER-SIMPLICITY!!!: EITHER [SCALE-Invariance Symmetry-BREAKING] MINUS [SCALE-Invariance Symmetry-RESTORING] via power-spectrum power-law algebraicity decays DIFFERENCES: ["red"-Pareto] MINUS ["pink"-Zipf Archimedes-HYPERBOLICITY INEVITABILITY]!!!

Energy Tracking Diagrams

NASA Astrophysics Data System (ADS)

Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

2016-02-01

Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

A convergent series expansion for hyperbolic systems of conservation laws

NASA Technical Reports Server (NTRS)

Harabetian, E.

1985-01-01

The discontinuities piecewise analytic initial value problem for a wide class of conservation laws is considered which includes the full three-dimensional Euler equations. The initial interaction at an arbitrary curved surface is resolved in time by a convergent series. Among other features the solution exhibits shock, contact, and expansion waves as well as sound waves propagating on characteristic surfaces. The expansion waves correspond to he one-dimensional rarefactions but have a more complicated structure. The sound waves are generated in place of zero strength shocks, and they are caused by mismatches in derivatives.

High resolution schemes and the entropy condition

NASA Technical Reports Server (NTRS)

Osher, S.; Chakravarthy, S.

1983-01-01

A systematic procedure for constructing semidiscrete, second order accurate, variation diminishing, five point band width, approximations to scalar conservation laws, is presented. These schemes are constructed to also satisfy a single discrete entropy inequality. Thus, in the convex flux case, convergence is proven to be the unique physically correct solution. For hyperbolic systems of conservation laws, this construction is used formally to extend the first author's first order accurate scheme, and show (under some minor technical hypotheses) that limit solutions satisfy an entropy inequality. Results concerning discrete shocks, a maximum principle, and maximal order of accuracy are obtained. Numerical applications are also presented.

On optimal control problem for conservation law modelling one class of highly re-entrant production systems

NASA Astrophysics Data System (ADS)

D'Apice, Ciro; Kogut, Peter I.

2017-07-01

We discuss the optimal control problem stated as the minimization in the L2-sense of the mismatch between the actual out-flux and a demand forecast for a hyperbolic conservation law that models a highly re-entrant production system. The output of the factory is described as a function of the work in progress and the position of the so-called push-pull point (PPP) where we separate the beginning of the factory employing a push policy from the end of the factory, which uses a pull policy.

The discrete one-sided Lipschitz condition for convex scalar conservation laws

NASA Technical Reports Server (NTRS)

Brenier, Yann; Osher, Stanley

1986-01-01

Physical solutions to convex scalar conservation laws satisfy a one-sided Lipschitz condition (OSLC) that enforces both the entropy condition and their variation boundedness. Consistency with this condition is therefore desirable for a numerical scheme and was proved for both the Godunov and the Lax-Friedrichs scheme--also, in a weakened version, for the Roe scheme, all of them being only first order accurate. A new, fully second order scheme is introduced here, which is consistent with the OSLC. The modified equation is considered and shows interesting features. Another second order scheme is then considered and numerical results are discussed.

Symmetrization of conservation laws with entropy for high-temperature hypersonic computations

NASA Technical Reports Server (NTRS)

Chalot, F.; Hughes, T. J. R.; Shakib, F.

1990-01-01

Results of Hughes, France, and Mallet are generalized to conservation law systems taking into account high-temperature effects. Symmetric forms of different equation sets are derived in terms of entropy variables. First, the case of a general divariant gas is studied; it can be specialized to the usual Navier-Stokes equations, as well as to situations where the gas is vibrationally excited, and undergoes equilibrium chemical reactions. The case of gas in thermochemical nonequilibrium is considered next. Transport phenomena, and in particular mass diffusion, are examined in the framework of symmetric advective-diffusive systems.

An unconstrained Lagrangian formulation and conservation laws for the Schrödinger map system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Paul, E-mail: smith@math.berkeley.edu

2014-05-15

We consider energy-critical Schrödinger maps from R{sup 2} into S{sup 2} and H{sup 2}. Viewing such maps with respect to orthonormal frames on the pullback bundle provides a gauge field formulation of the evolution. We show that this gauge field system is the set of Euler-Lagrange equations corresponding to an action that includes a Chern-Simons term. We also introduce the stress-energy tensor and derive conservation laws. In conclusion we offer comparisons between Schrödinger maps and the closely related Chern-Simons-Schrödinger system.

Triangle based TVD schemes for hyperbolic conservation laws

NASA Technical Reports Server (NTRS)

Durlofsky, Louis J.; Osher, Stanley; Engquist, Bjorn

1990-01-01

A triangle based total variation diminishing (TVD) scheme for the numerical approximation of hyperbolic conservation laws in two space dimensions is constructed. The novelty of the scheme lies in the nature of the preprocessing of the cell averaged data, which is accomplished via a nearest neighbor linear interpolation followed by a slope limiting procedures. Two such limiting procedures are suggested. The resulting method is considerably more simple than other triangle based non-oscillatory approximations which, like this scheme, approximate the flux up to second order accuracy. Numerical results for linear advection and Burgers' equation are presented.

Transforming conservation science and practice for a postnormal world.

PubMed

Colloff, Matthew J; Lavorel, Sandra; van Kerkhoff, Lorrae E; Wyborn, Carina A; Fazey, Ioan; Gorddard, Russell; Mace, Georgina M; Foden, Wendy B; Dunlop, Michael; Prentice, I Colin; Crowley, John; Leadley, Paul; Degeorges, Patrick

2017-10-01

We examine issues to consider when reframing conservation science and practice in the context of global change. New framings of the links between ecosystems and society are emerging that are changing peoples' values and expectations of nature, resulting in plural perspectives on conservation. Reframing conservation for global change can thus be regarded as a stage in the evolving relationship between people and nature rather than some recent trend. New models of how conservation links with transformative adaptation include how decision contexts for conservation can be reframed and integrated with an adaptation pathways approach to create new options for global-change-ready conservation. New relationships for conservation science and governance include coproduction of knowledge that supports social learning. New processes for implementing adaptation for conservation outcomes include deliberate practices used to develop new strategies, shift world views, work with conflict, address power and intergenerational equity in decisions, and build consciousness and creativity that empower agents to act. We argue that reframing conservation for global change requires scientists and practitioners to implement approaches unconstrained by discipline and sectoral boundaries, geopolitical polarities, or technical problematization. We consider a stronger focus on inclusive creation of knowledge and the interaction of this knowledge with societal values and rules is likely to result in conservation science and practice that meets the challenges of a postnormal world. © 2017 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

Non-Traditional Students and Critical Pedagogy: Transformative Practice and the Teaching of Criminal Law

ERIC Educational Resources Information Center

Menis, Susanna

2017-01-01

This article explores the practical implication of adopting critical pedagogy, and more specifically critical legal pedagogy, in the teaching of non-traditional students in higher education context. It is based on the teaching of criminal law at Birkbeck School of Law, addressing learning tasks which have been designed to enhance students'…

Child Support: The Dilemma of a Nation.

ERIC Educational Resources Information Center

Welch, Carol; And Others

This paper presents an overview of the development of child support in America. A review of the English common law from which U.S. laws evolved provides a glimpse into the ways that institutions of marriage and the family were viewed in the 19th century. The development of American law reflects the transformation of family structure by…

Optimal Control Modification for Robust Adaptation of Singularly Perturbed Systems with Slow Actuators

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.; Ishihara, Abraham; Stepanyan, Vahram; Boskovic, Jovan

2009-01-01

Recently a new optimal control modification has been introduced that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. This modification is based on an optimal control formulation to minimize the L2 norm of the tracking error. The optimal control modification adaptive law results in a stable adaptation in the presence of a large adaptive gain. This study examines the optimal control modification adaptive law in the context of a system with a time scale separation resulting from a fast plant with a slow actuator. A singular perturbation analysis is performed to derive a modification to the adaptive law by transforming the original system into a reduced-order system in slow time. The model matching conditions in the transformed time coordinate results in increase in the feedback gain and modification of the adaptive law.

Optimal Control Modification Adaptive Law for Time-Scale Separated Systems

NASA Technical Reports Server (NTRS)

Nguyen, Nhan T.

2010-01-01

Recently a new optimal control modification has been introduced that can achieve robust adaptation with a large adaptive gain without incurring high-frequency oscillations as with the standard model-reference adaptive control. This modification is based on an optimal control formulation to minimize the L2 norm of the tracking error. The optimal control modification adaptive law results in a stable adaptation in the presence of a large adaptive gain. This study examines the optimal control modification adaptive law in the context of a system with a time scale separation resulting from a fast plant with a slow actuator. A singular perturbation analysis is performed to derive a modification to the adaptive law by transforming the original system into a reduced-order system in slow time. A model matching conditions in the transformed time coordinate results in an increase in the actuator command that effectively compensate for the slow actuator dynamics. Simulations demonstrate effectiveness of the method.

25 CFR 162.231 - How can the land be used under an agricultural lease?

Code of Federal Regulations, 2010 CFR

2010-04-01

... with recognized principles of sustained yield management, integrated resource management planning, sound conservation practices, and other community goals as expressed in applicable tribal laws, leasing policies, or agricultural resource management plans. Appropriate stipulations or conservation plans must be...

Energy Alert 78-1, National Energy Act: A Special Report on the National Energy Conservation Policy Act of 1978.

ERIC Educational Resources Information Center

Association of Physical Plant Administrators of Universities and Colleges, Washington, DC.

This Energy Alert deals specifically with Public Law 95-619, the National Energy Conservation Policy Act of 1978 (NECPA). Title III, Part 1 of NECPA authorizes $900 million over a three-year period for grants to schools and hospitals for energy audits, technical assistance and energy conservation projects. This publication attempts to inform…

The Neotropical Migratory Bird Conservation Act: A Workshop to Discuss Improvements and a Brief Summary of First Year Results

Treesearch

David Mehlman; Heather Johnson; Bob Ford

2005-01-01

The Neotropical Migratory Bird Conservation Act (NMBCA; Public Law 106-247), passed by the U.S. Congress in 2000, establishes a matching grants program to fund projects that promote the conservation of migratory birds in the United States, Latin America, and the Caribbean. During its deliberations, the U.S. Congress recognized that migratory birds provide significant...

10 CFR Appendix C to Subpart C of... - Sampling Plan for Enforcement Testing of Distribution Transformers

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Sampling Plan for Enforcement Testing of Distribution Transformers C Appendix C to Subpart C of Part 429 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION... Testing of Distribution Transformers (a) When testing distribution transformers, the number of units in...

10 CFR Appendix C to Subpart C of... - Sampling Plan for Enforcement Testing of Distribution Transformers

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Sampling Plan for Enforcement Testing of Distribution Transformers C Appendix C to Subpart C of Part 429 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION... Testing of Distribution Transformers (a) When testing distribution transformers, the number of units in...

10 CFR Appendix C to Subpart C of... - Sampling Plan for Enforcement Testing of Distribution Transformers

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Sampling Plan for Enforcement Testing of Distribution Transformers C Appendix C to Subpart C of Part 429 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION... Testing of Distribution Transformers (a) When testing distribution transformers, the number of units in...

7 CFR 632.51 - Accord with environmental laws and orders.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 6 2014-01-01 2014-01-01 false Accord with environmental laws and orders. 632.51 Section 632.51 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL ABANDONED MINE PROGRAM Environment...

7 CFR 632.51 - Accord with environmental laws and orders.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 6 2012-01-01 2012-01-01 false Accord with environmental laws and orders. 632.51 Section 632.51 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL ABANDONED MINE PROGRAM Environment...

7 CFR 632.51 - Accord with environmental laws and orders.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 6 2010-01-01 2010-01-01 false Accord with environmental laws and orders. 632.51 Section 632.51 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL ABANDONED MINE PROGRAM Environment...

7 CFR 632.51 - Accord with environmental laws and orders.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 6 2011-01-01 2011-01-01 false Accord with environmental laws and orders. 632.51 Section 632.51 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL ABANDONED MINE PROGRAM Environment...

7 CFR 632.51 - Accord with environmental laws and orders.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 6 2013-01-01 2013-01-01 false Accord with environmental laws and orders. 632.51 Section 632.51 Agriculture Regulations of the Department of Agriculture (Continued) NATURAL RESOURCES CONSERVATION SERVICE, DEPARTMENT OF AGRICULTURE LONG TERM CONTRACTING RURAL ABANDONED MINE PROGRAM Environment...

44 CFR 59.4 - References.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and Water Conservation Fund Act (Pub. L. 89-578), and subsequent amendments thereto. (8) Water Resources Council, Principals and Standards for Planning, Water and Related Land Resources (38 FR 24778...), as amended Public Law 94-370. (5) Water Resources Planning Act (Pub. L. 89-90), as amended Public Law...

44 CFR 59.4 - References.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and Water Conservation Fund Act (Pub. L. 89-578), and subsequent amendments thereto. (8) Water Resources Council, Principals and Standards for Planning, Water and Related Land Resources (38 FR 24778...), as amended Public Law 94-370. (5) Water Resources Planning Act (Pub. L. 89-90), as amended Public Law...

50 CFR 648.3 - Relation to other laws.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Relation to other laws. 648.3 Section 648.3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES General Provisions § 648.3...

50 CFR 660.403 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Relation to other laws. 660.403 Section 660.403 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES West Coast Salmon Fisheries...

10 CFR 800.003 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Act, Public Law 95-91, title II, as amended by the National Energy Conservation Policy Act, Public Law 95-619, title VI, section 641. Applicant means a minority business enterprise which is seeking a loan... with a first-tier subcontractor of a DOE operating contractor in furtherance of the research...

10 CFR 800.003 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Act, Public Law 95-91, title II, as amended by the National Energy Conservation Policy Act, Public Law 95-619, title VI, section 641. Applicant means a minority business enterprise which is seeking a loan... with a first-tier subcontractor of a DOE operating contractor in furtherance of the research...

10 CFR 800.003 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Act, Public Law 95-91, title II, as amended by the National Energy Conservation Policy Act, Public Law 95-619, title VI, section 641. Applicant means a minority business enterprise which is seeking a loan... with a first-tier subcontractor of a DOE operating contractor in furtherance of the research...

10 CFR 800.003 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Act, Public Law 95-91, title II, as amended by the National Energy Conservation Policy Act, Public Law 95-619, title VI, section 641. Applicant means a minority business enterprise which is seeking a loan... with a first-tier subcontractor of a DOE operating contractor in furtherance of the research...

50 CFR 660.403 - Relation to other laws.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Relation to other laws. 660.403 Section 660.403 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES West Coast Salmon Fisheries...

Faraday's law, Lenz's law, and conservation of energy

NASA Astrophysics Data System (ADS)

Wood, Lowell T.; Rottmann, Ray M.; Barrera, Regina

2004-03-01

We describe an experiment in which the induced electromotive force in a coil caused by an accelerating magnet and the position of the moving magnet are measured as a function of the time. When the circuit is completed by adding an appropriate load resistor, a current that opposes the flux change is generated in the coil. This current causes a magnetic field in the coil which decreases the acceleration of the rising magnet, as is evident from the position versus time data. The circuit provides a direct observation of effects that are a consequence of Lenz's law. The energy dissipated by the resistance in the circuit is shown to equal the loss in mechanical energy of the system to within experimental error, thus demonstrating conservation of energy. Students in introductory physics courses have performed this experiment successfully.

The Clawpack Community of Codes

NASA Astrophysics Data System (ADS)

Mandli, K. T.; LeVeque, R. J.; Ketcheson, D.; Ahmadia, A. J.

2014-12-01

Clawpack, the Conservation Laws Package, has long been one of the standards for solving hyperbolic conservation laws but over the years has extended well beyond this role. Today a community of open-source codes have been developed that address a multitude of different needs including non-conservative balance laws, high-order accurate methods, and parallelism while remaining extensible and easy to use, largely by the judicious use of Python and the original Fortran codes that it wraps. This talk will present some of the recent developments in projects under the Clawpack umbrella, notably the GeoClaw and PyClaw projects. GeoClaw was originally developed as a tool for simulating tsunamis using adaptive mesh refinement but has since encompassed a large number of other geophysically relevant flows including storm surge and debris-flows. PyClaw originated as a Python version of the original Clawpack algorithms but has since been both a testing ground for new algorithmic advances in the Clawpack framework but also an easily extensible framework for solving hyperbolic balance laws. Some of these extensions include the addition of WENO high-order methods, massively parallel capabilities, and adaptive mesh refinement technologies, made possible largely by the flexibility of the Python language and community libraries such as NumPy and PETSc. Because of the tight integration with Python tecnologies, both packages have benefited also from the focus on reproducibility in the Python community, notably IPython notebooks.

Wildlife and wildlife management in Tanzania.

PubMed

Caro, Tim; Davenport, Tim R B

2016-08-01

Tanzania, arguably mainland Africa's most important nation for conservation, is losing habitat and natural resources rapidly. Moving away from a charcoal energy base and developing sustainable finance mechanisms for natural forests are critical to slowing persistent deforestation. Addressing governance and capacity deficits, including law enforcement, technical skills, and funding, across parts of the wildlife sector are key to effective wildlife protection. These changes could occur in tandem with bringing new models of natural resource management into play that include capacity building, corporate payment for ecosystem services, empowering nongovernmental organizations in law enforcement, greater private-sector involvement, and novel community conservation strategies. The future of Tanzania's wildlife looks uncertain-as epitomized by the current elephant crisis-unless the country confronts issues of governance, embraces innovation, and fosters greater collaboration with the international community. © 2015 Society for Conservation Biology.

Conservation laws and symmetries in stochastic thermodynamics.

PubMed

Polettini, Matteo; Bulnes-Cuetara, Gregory; Esposito, Massimiliano

2016-11-01

Phenomenological nonequilibrium thermodynamics describes how fluxes of conserved quantities, such as matter, energy, and charge, flow from outer reservoirs across a system and how they irreversibly degrade from one form to another. Stochastic thermodynamics is formulated in terms of probability fluxes circulating in the system's configuration space. The consistency of the two frameworks is granted by the condition of local detailed balance, which specifies the amount of physical quantities exchanged with the reservoirs during single transitions between configurations. We demonstrate that the topology of the configuration space crucially determines the number of independent thermodynamic affinities (forces) that the reservoirs generate across the system and provides a general algorithm that produces the fundamental affinities and their conjugate currents contributing to the total dissipation, based on the interplay between macroscopic conservations laws for the currents and microscopic symmetries of the affinities.

Energetics of oscillating lifting surfaces using integral conservation laws

NASA Technical Reports Server (NTRS)

Ahmadi, Ali R.; Widnall, Sheila E.

1987-01-01

The energetics of oscillating flexible lifting surfaces in two and three dimensions is calculated by the use of integral conservation laws in inviscid incompressible flow for general and harmonic transverse oscillations. Total thrust is calculated from the momentum theorem and energy loss rate due to vortex shedding in the wake from the principle of conservation of mechanical energy. Total power required to maintain the oscillations and hydrodynamic efficiency are also determined. In two dimensions, the results are obtained in closed form. In three dimensions, the distribution of vorticity on the lifting surface is also required as input to the calculations. Thus, unsteady lifting-surface theory must be used as well. The analysis is applicable to oscillating lifting surfaces of arbitrary planform, aspect ratio, and reduced frequency and does not require calculation of the leading-edge thrust.

Criticality in conserved dynamical systems: experimental observation vs. exact properties.

PubMed

Marković, Dimitrije; Gros, Claudius; Schuelein, André

2013-03-01

Conserved dynamical systems are generally considered to be critical. We study a class of critical routing models, equivalent to random maps, which can be solved rigorously in the thermodynamic limit. The information flow is conserved for these routing models and governed by cyclic attractors. We consider two classes of information flow, Markovian routing without memory and vertex routing involving a one-step routing memory. Investigating the respective cycle length distributions for complete graphs, we find log corrections to power-law scaling for the mean cycle length, as a function of the number of vertices, and a sub-polynomial growth for the overall number of cycles. When observing experimentally a real-world dynamical system one normally samples stochastically its phase space. The number and the length of the attractors are then weighted by the size of their respective basins of attraction. This situation is equivalent, for theory studies, to "on the fly" generation of the dynamical transition probabilities. For the case of vertex routing models, we find in this case power law scaling for the weighted average length of attractors, for both conserved routing models. These results show that the critical dynamical systems are generically not scale-invariant but may show power-law scaling when sampled stochastically. It is hence important to distinguish between intrinsic properties of a critical dynamical system and its behavior that one would observe when randomly probing its phase space.

The Space-Time Conservation Element and Solution Element Method: A New High-Resolution and Genuinely Multidimensional Paradigm for Solving Conservation Laws. 1; The Two Dimensional Time Marching Schemes

NASA Technical Reports Server (NTRS)

Chang, Sin-Chung; Wang, Xiao-Yen; Chow, Chuen-Yen

1998-01-01

A new high resolution and genuinely multidimensional numerical method for solving conservation laws is being, developed. It was designed to avoid the limitations of the traditional methods. and was built from round zero with extensive physics considerations. Nevertheless, its foundation is mathmatically simple enough that one can build from it a coherent, robust. efficient and accurate numerical framework. Two basic beliefs that set the new method apart from the established methods are at the core of its development. The first belief is that, in order to capture physics more efficiently and realistically, the modeling, focus should be placed on the original integral form of the physical conservation laws, rather than the differential form. The latter form follows from the integral form under the additional assumption that the physical solution is smooth, an assumption that is difficult to realize numerically in a region of rapid chance. such as a boundary layer or a shock. The second belief is that, with proper modeling of the integral and differential forms themselves, the resulting, numerical solution should automatically be consistent with the properties derived front the integral and differential forms, e.g., the jump conditions across a shock and the properties of characteristics. Therefore a much simpler and more robust method can be developed by not using the above derived properties explicitly.

Thermodynamics of cosmological matter creation.

PubMed

Prigogine, I; Geheniau, J; Gunzig, E; Nardone, P

1988-10-01

A type of cosmological history that includes large-scale entropy production is proposed. These cosmologies are based on reinterpretation of the matter-energy stress tensor in Einstein's equations. This modifies the usual adiabatic energy conservation laws, thereby including irreversible matter creation. This creation corresponds to an irreversible energy flow from the gravitational field to the created matter constituents. This point of view results from consideration of the thermodynamics of open systems in the framework of cosmology. It is shown that the second law of thermodynamics requires that space-time transforms into matter, while the inverse transformation is forbidden. It appears that the usual initial singularity associated with the big bang is structurally unstable with respect to irreversible matter creation. The corresponding cosmological history therefore starts from an instability of the vacuum rather than from a singularity. This is exemplified in the framework of a simple phenomenological model that leads to a three-stage cosmology: the first drives the cosmological system from the initial instability to a de Sitter regime, and the last connects with the usual matter-radiation Robertson-Walker universe. Matter as well as entropy creation occurs during the first two stages, while the third involves the traditional cosmological evolution. A remarkable fact is that the de Sitter stage appears to be an attractor independent of the initial fluctuation. This is also the case for all the physical predictions involving the present Robertson-Walker universe. Most results obtained previously, in the framework of quantum field theory, can now be obtained on a macroscopic basis. It is shown that this description leads quite naturally to the introduction of primeval black holes as the intermediate stage between the Minkowski vacuum and the present matter-radiation universe. The instability at the origin of the universe is the result of fluctuations of the vacuum in which black holes act as membranes that stabilize these fluctuations. In short, black holes will be produced by and "inverse" Hawking radiation process and, once formed, will decompose into "real" matter through the usual Hawking radiation. In this way, the irreversible transformation of space-time into matter can be described as a phase separation between matter and gravitation in which black holes play the role of "critical nuclei."

Uniqueness of Mass-Conserving Self-similar Solutions to Smoluchowski's Coagulation Equation with Inverse Power Law Kernels

NASA Astrophysics Data System (ADS)

Laurençot, Philippe

2018-03-01

Uniqueness of mass-conserving self-similar solutions to Smoluchowski's coagulation equation is shown when the coagulation kernel K is given by K(x,x_*)=2(x x_*)^{-α } , (x,x_*)\\in (0,∞)^2 , for some α >0.

Collections Care: A Basic Reference Shelflist.

ERIC Educational Resources Information Center

de Torres, Amparo R., Ed.

This is an extensive bibliography of reference sources--i.e., books and articles--that relate to the care and conservation of library, archival, and museum collections. Bibliographies are presented under the following headings: (1) General Information; (2) Basic Collections Care; (3) Architectural Conservation; (4) Collections Management: Law,…

An Easy Way to One-Dimensional Elastic Collisions

ERIC Educational Resources Information Center

Sztrajman, Jorge; Sztrajman, Alejandro

2017-01-01

The aim of this paper is to propose a method for solving head-on elastic collisions, without algebraic complications, to emphasize the use of the fundamental conservations laws. Head-on elastic collisions are treated in many physics textbooks as examples of conservation of momentum and kinetic energy.

Classicality condition on a system observable in a quantum measurement and a relative-entropy conservation law

NASA Astrophysics Data System (ADS)

Kuramochi, Yui; Ueda, Masahito

2015-03-01

We consider the information flow on a system observable X corresponding to a positive-operator-valued measure under a quantum measurement process Y described by a completely positive instrument from the viewpoint of the relative entropy. We establish a sufficient condition for the relative-entropy conservation law which states that the average decrease in the relative entropy of the system observable X equals the relative entropy of the measurement outcome of Y , i.e., the information gain due to measurement. This sufficient condition is interpreted as an assumption of classicality in the sense that there exists a sufficient statistic in a joint successive measurement of Y followed by X such that the probability distribution of the statistic coincides with that of a single measurement of X for the premeasurement state. We show that in the case when X is a discrete projection-valued measure and Y is discrete, the classicality condition is equivalent to the relative-entropy conservation for arbitrary states. The general theory on the relative-entropy conservation is applied to typical quantum measurement models, namely, quantum nondemolition measurement, destructive sharp measurements on two-level systems, a photon counting, a quantum counting, homodyne and heterodyne measurements. These examples except for the nondemolition and photon-counting measurements do not satisfy the known Shannon-entropy conservation law proposed by Ban [M. Ban, J. Phys. A: Math. Gen. 32, 1643 (1999), 10.1088/0305-4470/32/9/012], implying that our approach based on the relative entropy is applicable to a wider class of quantum measurements.

18 CFR 385.603 - Settlement of negotiations before a settlement judge (Rule 603).

Code of Federal Regulations, 2014 CFR

2014-04-01

... negotiations before a settlement judge (Rule 603). 385.603 Section 385.603 Conservation of Power and Water... PROCEDURE Conferences, Settlements, and Stipulations § 385.603 Settlement of negotiations before a... administrative law judge appointed by the Chief Administrative Law Judge to conduct settlement negotiations under...

18 CFR 385.603 - Settlement of negotiations before a settlement judge (Rule 603).

Code of Federal Regulations, 2011 CFR

2011-04-01

... negotiations before a settlement judge (Rule 603). 385.603 Section 385.603 Conservation of Power and Water... PROCEDURE Conferences, Settlements, and Stipulations § 385.603 Settlement of negotiations before a... administrative law judge appointed by the Chief Administrative Law Judge to conduct settlement negotiations under...

18 CFR 385.603 - Settlement of negotiations before a settlement judge (Rule 603).

Code of Federal Regulations, 2013 CFR

2013-04-01

... negotiations before a settlement judge (Rule 603). 385.603 Section 385.603 Conservation of Power and Water... PROCEDURE Conferences, Settlements, and Stipulations § 385.603 Settlement of negotiations before a... administrative law judge appointed by the Chief Administrative Law Judge to conduct settlement negotiations under...

18 CFR 385.603 - Settlement of negotiations before a settlement judge (Rule 603).

Code of Federal Regulations, 2010 CFR

2010-04-01

... negotiations before a settlement judge (Rule 603). 385.603 Section 385.603 Conservation of Power and Water... PROCEDURE Conferences, Settlements, and Stipulations § 385.603 Settlement of negotiations before a... administrative law judge appointed by the Chief Administrative Law Judge to conduct settlement negotiations under...

18 CFR 385.603 - Settlement of negotiations before a settlement judge (Rule 603).

Code of Federal Regulations, 2012 CFR

2012-04-01

... negotiations before a settlement judge (Rule 603). 385.603 Section 385.603 Conservation of Power and Water... PROCEDURE Conferences, Settlements, and Stipulations § 385.603 Settlement of negotiations before a... administrative law judge appointed by the Chief Administrative Law Judge to conduct settlement negotiations under...

10 CFR 490.7 - Relationship to other law.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Relationship to other law. 490.7 Section 490.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.7... conversion to, light duty alternative fueled motor vehicles in violation of applicable regulations of any...

10 CFR 490.7 - Relationship to other law.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Relationship to other law. 490.7 Section 490.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.7... conversion to, light duty alternative fueled motor vehicles in violation of applicable regulations of any...

10 CFR 490.7 - Relationship to other law.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Relationship to other law. 490.7 Section 490.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.7... conversion to, light duty alternative fueled motor vehicles in violation of applicable regulations of any...

10 CFR 490.7 - Relationship to other law.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 3 2011-01-01 2011-01-01 false Relationship to other law. 490.7 Section 490.7 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM General Provisions § 490.7... conversion to, light duty alternative fueled motor vehicles in violation of applicable regulations of any...

50 CFR 660.2 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Relation to other laws. 660.2 Section 660.2 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF WEST COAST STATES General § 660.2 Relation to...

A Solar Sailcraft Simulation Application

ERIC Educational Resources Information Center

Celeda, Tomáš

2013-01-01

An application was created to encourage students' practical knowledge of gravitational fields, the law of conservation of energy and other phenomena, such as gravitational slingshots. The educational software simulates the flight of a solar sail spacecraft between two planets of the Solar System using the laws of gravity and radiation…

25 CFR 166.213 - Must I comply with any standards of conduct if I am granted a permit?

Code of Federal Regulations, 2010 CFR

2010-04-01

... grazing operations in accordance with the principles of sustained yield management, agricultural resource management planning, sound conservation practices, and other community goals as expressed in tribal laws, agricultural resource management plans, and similar sources. (b) Comply with all applicable laws, ordinances...

25 CFR 161.308 - Must a permittee comply with standards of conduct if granted a permit?

Code of Federal Regulations, 2010 CFR

2010-04-01

... grazing operations in accordance with the principles of sustained yield management, agricultural resource management planning, sound conservation practices, and other community goals as expressed in Navajo Nation laws, agricultural resource management plans, and similar sources. (b) Comply with all applicable laws...

Project Physics Tests 3, The Triumph of Mechanics.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

Test items relating to Project Physics Unit 3 are presented in this booklet. Included are 70 multiple-choice and 20 problem-and-essay questions. Concepts of mechanics are examined on energy, momentum, kinetic theory of gases, pulse analyses, "heat death," water waves, power, conservation laws, normal distribution, thermodynamic laws, and…

76 FR 70376 - Efficiency and Renewables Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-14

...-Voltage Dry-Type Distribution Transformers. The Liquid Immersed and Medium-Voltage Dry- Type Group (MV... of distribution transformers, as authorized by the Energy Policy Conservation Act (EPCA) of 1975, as... negotiated rulemaking process to develop proposed energy efficiency standards for distribution transformers...

Different Paths to Some Fundamental Physical Laws: Relativistic Polarization of a Moving Magnetic Dipole

ERIC Educational Resources Information Center

Kholmetskii, Alexander L.; Yarman, T.

2010-01-01

In this paper we consider the relativistic polarization of a moving magnetic dipole and show that this effect can be understood via the relativistic generalization of Kirchhoff's first law to a moving closed circuit with a steady current. This approach allows us to better understand the law of relativistic transformation of four-current density…

The Unraveling of No Child Left Behind: How Negotiated Changes Transform the Law

ERIC Educational Resources Information Center

Sunderman, Gail L.

2006-01-01

Over the past two years, the U.S. Department of Education's (ED) has made such extensive compromises in implementing the No Child Left Behind Act of 2001 (NCLB)that the law's legitimacy is in serious question. In response to growing state and local opposition to the law, political and professional criticisms of its requirements, and the…

77 FR 50720 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-22

...The National Science Foundation (NSF) is required to publish a notice of requests to modify permits issued to conduct activities regulated under the Antarctic Conservation Act of 1978,, Public Law 95- 541. NSF has published regulations under the Antarctic Conservation Act at Title 45 Part 670 of the Code of Federal Regulations. This is the required notice of a requested permit modification.

Interdisciplinary Student/Teacher Materials in Energy, the Environment, and the Economy: 1, How a Bill Becomes a Law to Conserve Energy, Grades 9, 11, 12.

ERIC Educational Resources Information Center

Brock, Phyllis; And Others

This instructional unit for secondary school students is designed to integrate facts and concepts of energy, environment, and economics into the study of the process of making and applying a law (the fifty-five mile-per-hour speed limit law). The unit contains activities on the legislative process designed to fit into traditional segments of…

18 CFR 11.8 - Adjustment of annual charges.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Adjustment of annual charges. 11.8 Section 11.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... in effect as fixed unless changed as authorized by law. [51 FR 24318, July 3, 1986] ...

18 CFR 11.8 - Adjustment of annual charges.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Adjustment of annual charges. 11.8 Section 11.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... in effect as fixed unless changed as authorized by law. [51 FR 24318, July 3, 1986] ...

18 CFR 11.8 - Adjustment of annual charges.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Adjustment of annual charges. 11.8 Section 11.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... in effect as fixed unless changed as authorized by law. [51 FR 24318, July 3, 1986] ...

18 CFR 11.8 - Adjustment of annual charges.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Adjustment of annual charges. 11.8 Section 11.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... in effect as fixed unless changed as authorized by law. [51 FR 24318, July 3, 1986] ...

18 CFR 11.8 - Adjustment of annual charges.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Adjustment of annual charges. 11.8 Section 11.8 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... in effect as fixed unless changed as authorized by law. [51 FR 24318, July 3, 1986] ...

36 CFR 242.4 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Conservation Act, Public Law 96-487, 94 Stat. 2371, (codified, as amended, in scattered sections of 16 U.S.C... 808 of ANILCA. Conservation of healthy populations of fish and wildlife means the maintenance of fish... navigable and non-navigable waters in which the United States has reserved water rights. Fish and wildlife...

77 FR 45368 - Draft Environmental Assessment, Habitat Conservation Plan, and Application for an Incidental Take...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-31

... otherwise lawful activities associated with operation, maintenance, and decommissioning of a 28-turbine wind... occur due to operation, maintenance, and decommissioning of 28 wind turbines. The proposed conservation... 21 years during operations, maintenance, and decommissioning activities related to CPP's 28-turbine...

76 FR 1190 - Back Bay National Wildlife Refuge, City of Virginia Beach, VA; Final Comprehensive Conservation...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-07

... purpose of ``* * * the conservation of the wetlands of the Nation in order to maintain the public benefits... benefits our resource decisions, maintaining a proactive law enforcement program, protecting cultural...; developing new hiking trails; and developing and designing a new headquarters/visitor contact station...

50 CFR 679.3 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

... fishery and sport fishery in the East Area of the Salmon Management Area, defined at § 679.2, is delegated....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... fishing for groundfish. (1) The conservation and management of groundfish in waters of the territorial sea...

50 CFR 679.3 - Relation to other laws.

Code of Federal Regulations, 2013 CFR

2013-10-01

... fishery and sport fishery in the East Area of the Salmon Management Area, defined at § 679.2, is delegated....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... fishing for groundfish. (1) The conservation and management of groundfish in waters of the territorial sea...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2013 CFR

2013-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2011 CFR

2011-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

14 CFR 313.6 - Energy statements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Energy statements. 313.6 Section 313.6... REGULATIONS IMPLEMENTATION OF THE ENERGY POLICY AND CONSERVATION ACT § 313.6 Energy statements. (a) Each major... action taken or to be taken upon energy efficiency and conservation. The administrative law judge or the...

14 CFR 313.6 - Energy statements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Energy statements. 313.6 Section 313.6... REGULATIONS IMPLEMENTATION OF THE ENERGY POLICY AND CONSERVATION ACT § 313.6 Energy statements. (a) Each major... action taken or to be taken upon energy efficiency and conservation. The administrative law judge or the...

14 CFR 313.6 - Energy statements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Energy statements. 313.6 Section 313.6... REGULATIONS IMPLEMENTATION OF THE ENERGY POLICY AND CONSERVATION ACT § 313.6 Energy statements. (a) Each major... action taken or to be taken upon energy efficiency and conservation. The administrative law judge or the...

14 CFR 313.6 - Energy statements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Energy statements. 313.6 Section 313.6... REGULATIONS IMPLEMENTATION OF THE ENERGY POLICY AND CONSERVATION ACT § 313.6 Energy statements. (a) Each major... action taken or to be taken upon energy efficiency and conservation. The administrative law judge or the...

14 CFR 313.6 - Energy statements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Energy statements. 313.6 Section 313.6... REGULATIONS IMPLEMENTATION OF THE ENERGY POLICY AND CONSERVATION ACT § 313.6 Energy statements. (a) Each major... action taken or to be taken upon energy efficiency and conservation. The administrative law judge or the...

Project Physics Text 3, The Triumph of Mechanics.

ERIC Educational Resources Information Center

Harvard Univ., Cambridge, MA. Harvard Project Physics.

Mechanical theories are presented in this unit of the Project Physics text for senior high students. Collisions, Newton's laws, isolated systems, and Leibniz' concept are discussed, leading to conservation of mass and momentum. Energy conservation is analyzed in terms of mechanical energy, heat energy, steam engines, Watt's engine, Joule's…

Challenges in global biodiversity conservation and solutions that cross sociology, politics, economics and ecology

PubMed Central

Hoban, Sean; Vernesi, Cristiano

2012-01-01

The study and practice of conservation biology is inherently interdisciplinary, addresses short and long time-scales and occurs within complex human–natural interfaces. Zoos and aquaria, in partnership with researchers, other non-government organizations, government, industry and educators, are combining knowledge of species and ecosystems with economics, psychology and law to create solutions for conserving biodiversity. From 22 to 25 May, the Conservation Forum of the European Association of Zoos and Aquaria was a venue for discussing conservation research, education and interventions, from the scale of villages to global policy. PMID:22832128

Challenges in global biodiversity conservation and solutions that cross sociology, politics, economics and ecology.

PubMed

Hoban, Sean; Vernesi, Cristiano

2012-12-23

The study and practice of conservation biology is inherently interdisciplinary, addresses short and long time-scales and occurs within complex human-natural interfaces. Zoos and aquaria, in partnership with researchers, other non-government organizations, government, industry and educators, are combining knowledge of species and ecosystems with economics, psychology and law to create solutions for conserving biodiversity. From 22 to 25 May, the Conservation Forum of the European Association of Zoos and Aquaria was a venue for discussing conservation research, education and interventions, from the scale of villages to global policy.

Novel ecosystems: Governance and conservation in the age of the Anthropocene.

PubMed

Clement, Sarah; Standish, Rachel J

2018-02-15

Meeting conservation objectives in an era of global environmental change has precipitated debate about where and how to intervene. Ecological and social values of novel ecosystems are particularly contested. Governance has a role to play, but this role is underexplored. Here, we critically review the novel ecosystems literature to identify challenges that fall within the realm of governance. Using a conceptual framework for analysing adaptive governance, we consider how governance could help address five challenges. Specifically, we argue that reforming governance can support the re-framing of policy objectives for ecosystems where transformation is likely, and in doing so, it could highlight the tensions between the emergence of novel ecosystems on the one hand and cultural expectations about how ecosystems should look on the other. We discuss the influence of power, authority and administrative competence on conservation efforts in times of environmental change. We consider how buffering can address translational mismatch between conventional conservation policy and modern ecological reality. This review provides insights into how governance reform could enable more adaptive responses to transformative changes, such as novel ecosystems, while remaining committed to achieving conservation outcomes. Indeed, at their best, adaptive responses would encompass the reality of ecological transformation while being sympathetic to concerns about undesirable outcomes. Connections between researchers in the fields of governance, ecology and conservation could help to achieve these twin aims. We provide examples of governance and policy-making techniques that can support context-specific governance reform that supports more effective conservation in the Anthropocene. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Hierarchy of Models for Two-Phase Flows

NASA Astrophysics Data System (ADS)

Bouchut, F.; Brenier, Y.; Cortes, J.; Ripoll, J.-F.

2000-12-01

We derive a hierarchy of models for gas-liquid two-phase flows in the limit of infinite density ratio, when the liquid is assumed to be incompressible. The starting model is a system of nonconservative conservation laws with relaxation. At first order in the density ratio, we get a simplified system with viscosity, while at the limit we obtain a system of two conservation laws, the system of pressureless gases with constraint and undetermined pressure. Formal properties of this constraint model are provided, and sticky blocks solutions are introduced. We propose numerical methods for this last model, and the results are compared with the two previous models.

Numerical methods for systems of conservation laws of mixed type using flux splitting

NASA Technical Reports Server (NTRS)

Shu, Chi-Wang

1990-01-01

The essentially non-oscillatory (ENO) finite difference scheme is applied to systems of conservation laws of mixed hyperbolic-elliptic type. A flux splitting, with the corresponding Jacobi matrices having real and positive/negative eigenvalues, is used. The hyperbolic ENO operator is applied separately. The scheme is numerically tested on the van der Waals equation in fluid dynamics. Convergence was observed with good resolution to weak solutions for various Riemann problems, which are then numerically checked to be admissible as the viscosity-capillarity limits. The interesting phenomena of the shrinking of elliptic regions if they are present in the initial conditions were also observed.

Analyzing Lie symmetry and constructing conservation laws for time-fractional Benny-Lin equation

NASA Astrophysics Data System (ADS)

Rashidi, Saeede; Hejazi, S. Reza

This paper investigates the invariance properties of the time fractional Benny-Lin equation with Riemann-Liouville and Caputo derivatives. This equation can be reduced to the Kawahara equation, fifth-order Kdv equation, the Kuramoto-Sivashinsky equation and Navier-Stokes equation. By using the Lie group analysis method of fractional differential equations (FDEs), we derive Lie symmetries for the Benny-Lin equation. Conservation laws for this equation are obtained with the aid of the concept of nonlinear self-adjointness and the fractional generalization of the Noether’s operators. Furthermore, by means of the invariant subspace method, exact solutions of the equation are also constructed.

General phase transition models for vehicular traffic with point constraints on the flow

NASA Astrophysics Data System (ADS)

Dal Santo, E.; Rosini, M. D.; Dymski, N.; Benyahia, M.

2017-12-01

We generalize the phase transition model studied in [R. Colombo. Hyperbolic phase transition in traffic flow.\\ SIAM J.\\ Appl.\\ Math., 63(2):708-721, 2002], that describes the evolution of vehicular traffic along a one-lane road. Two different phases are taken into account, according to whether the traffic is low or heavy. The model is given by a scalar conservation law in the \\emph{free-flow} phase and by a system of two conservation laws in the \\emph{congested} phase. In particular, we study the resulting Riemann problems in the case a local point constraint on the flux of the solutions is enforced.

A new six-component super soliton hierarchy and its self-consistent sources and conservation laws

NASA Astrophysics Data System (ADS)

Han-yu, Wei; Tie-cheng, Xia

2016-01-01

A new six-component super soliton hierarchy is obtained based on matrix Lie super algebras. Super trace identity is used to furnish the super Hamiltonian structures for the resulting nonlinear super integrable hierarchy. After that, the self-consistent sources of the new six-component super soliton hierarchy are presented. Furthermore, we establish the infinitely many conservation laws for the integrable super soliton hierarchy. Project supported by the National Natural Science Foundation of China (Grant Nos. 11547175, 11271008 and 61072147), the First-class Discipline of University in Shanghai, China, and the Science and Technology Department of Henan Province, China (Grant No. 152300410230).

A-Posteriori Error Estimation for Hyperbolic Conservation Laws with Constraint

NASA Technical Reports Server (NTRS)

Barth, Timothy

2004-01-01

This lecture considers a-posteriori error estimates for the numerical solution of conservation laws with time invariant constraints such as those arising in magnetohydrodynamics (MHD) and gravitational physics. Using standard duality arguments, a-posteriori error estimates for the discontinuous Galerkin finite element method are then presented for MHD with solenoidal constraint. From these estimates, a procedure for adaptive discretization is outlined. A taxonomy of Green's functions for the linearized MHD operator is given which characterizes the domain of dependence for pointwise errors. The extension to other constrained systems such as the Einstein equations of gravitational physics are then considered. Finally, future directions and open problems are discussed.

Resonant behaviour of MHD waves on magnetic flux tubes. III - Effect of equilibrium flow

NASA Technical Reports Server (NTRS)

Goossens, Marcel; Hollweg, Joseph V.; Sakurai, Takashi

1992-01-01

The Hollweg et al. (1990) analysis of MHD surface waves in a stationary equilibrium is extended. The conservation laws and jump conditions at Alfven and slow resonance points obtained by Sakurai et al. (1990) are generalized to include an equilibrium flow, and the assumption that the Eulerian perturbation of total pressure is constant is recovered as the special case of the conservation law for an equilibrium with straight magnetic field lines and flow along the magnetic field lines. It is shown that the conclusions formulated by Hollweg et al. are still valid for the straight cylindrical case. The effect of curvature is examined.

The decay of the proton

NASA Astrophysics Data System (ADS)

Weinberg, S.

1981-06-01

The principal decay modes of subatomic particles are governed by fundamental conservation laws, and it is recounted how traditional views of conservation laws have been altered by the development of modern theories of elementary particle interactions. Proton decay experiments have gradually increased the empirical lower boundary on the lifetime of the proton. It is now known to have a lifetime at least 10 to the 30th times the age of the universe, but recent theoretical work is cited as an indication that this fundamental constituent of matter is not immortal. The conclusion is that all matter will eventually disintegrate if the proton indeed does not live forever.

Self-adjusting grid methods for one-dimensional hyperbolic conservation laws

NASA Technical Reports Server (NTRS)

Harten, A.; Hyman, J. M.

1983-01-01

The automatic adjustment of a grid which follows the dynamics of the numerical solution of hyperbolic conservation laws is given. The grid motion is determined by averaging the local characteristic velocities of the equations with respect to the amplitudes of the signals. The resulting algorithm is a simple extension of many currently popular Godunov-type methods. Computer codes using one of these methods can be easily modified to add the moving mesh as an option. Numerical examples are given that illustrate the improved accuracy of Godunov's and Roe's methods on a self-adjusting mesh. Previously announced in STAR as N83-15008

Local conservation laws and the structure of the many-body localized states.

PubMed

Serbyn, Maksym; Papić, Z; Abanin, Dmitry A

2013-09-20

We construct a complete set of local integrals of motion that characterize the many-body localized (MBL) phase. Our approach relies on the assumption that local perturbations act locally on the eigenstates in the MBL phase, which is supported by numerical simulations of the random-field XXZ spin chain. We describe the structure of the eigenstates in the MBL phase and discuss the implications of local conservation laws for its nonequilibrium quantum dynamics. We argue that the many-body localization can be used to protect coherence in the system by suppressing relaxation between eigenstates with different local integrals of motion.

Similarity considerations and conservation laws for magneto-static atmospheres

NASA Technical Reports Server (NTRS)

Webb, G. M.

1986-01-01

The equations of magnetohydrostatic equilibria for a plasma in a gravitational field are investigated analytically. For equilibria with one ignorable spatial coordinate, the equations reduce to a single nonlinear elliptic equation for the magnetic potential. Similarity solutions of the elliptic equation are obtained for the case of an isothermal atmosphere in a uniform gravitational field. The solutions are obtained from a consideration of the invariance group of the elliptic equation. The importance of symmetries of the elliptic equation also appears in the determination of conservation laws. It turns out that the elliptic equation can be written as a variational principle, and the symmetries of the variational functional lead (via Noether's theorem) to conservation laws for the equation. As an example of the application of the similarity solutions, a model magnetostatic atmosphere is constructed in which the current density J is proportional to the cube of the magnetic potential, and falls off exponentially with distance vertical to the base, with an 'e-folding' distance equal to the gravitational scale height. The solutions show the interplay between the gravitational force, the J x B force (B, magnetic field induction) and the gas pressure gradient.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai Ronggen; Cao Liming; Pang Dawei

Recently Gibbons et al. in [G. W. Gibbons et al. Class. Quant. Grav. 22, 1503 (2005)] defined a set of conserved quantities for Kerr-AdS black holes with the maximal number of rotation parameters in arbitrary dimension. This set of conserved quantities is defined with respect to a frame which is nonrotating at infinity. On the other hand, there is another set of conserved quantities for Kerr-AdS black holes, defined by Hawking et al. in [Hawking et al. Phys. Rev. D 59, 064005 (1999)], which is measured relative to a frame rotating at infinity. Gibbons et al. explicitly showed that themore » quantities defined by them satisfy the first law of black hole thermodynamics, while those quantities defined by Hawking et al. do not obey the first law. In this paper we discuss thermodynamics of dual CFTs to the Kerr-AdS black holes by mapping the bulk thermodynamic quantities to the boundary of the AdS space. We find that thermodynamic quantities of dual CFTs satisfy the first law of thermodynamics and Cardy-Verlinde formula only when these thermodynamic quantities result from the set of bulk quantities given by Hawking et al.. We discuss the implication of our results.« less

Pacific Northwest Electric Power Planning and Conservation Act : Legislative History of the Act to Assist the Electrical Consumers of the Pacific Northwest through use of the Federal Columbia River Power System to Achieve Cost-Effective Energy Conservation : P.L. 96-501, 94 Stat. 2697.

DOE Office of Scientific and Technical Information (OSTI.GOV)

United States. Bonneville Power Administration.

1981-01-01

The Pacific Northwest Electric Power Planning and Conservation Act became effective when it was signed into law by President Carter on December 5, 1980. This ended a four-year debate over legislation designed to plan and coordinate the region's energy future. This legislative history is an abbreviated version taken from the larger historical file maintained by the BPA Law Library. It is intended to assist BPA personnel and others who are studying the Northwest Power Act and working on its implementation. The documents included were selected for their value in determining what Congress meant in enacting the statute and to providemore » the researcher with a starting point for further investigation. These documents include: a history of the Act, a chronology of the legislative action leading to passage of the law; a section-by-section analysis of the Act; the Congressional Records of Senate and House debates on the bill and its amendments, and a list of Congressional committee hearings.« less