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Sample records for legal problem solver

  1. Differential equations problem solver

    CERN Document Server

    Arterburn, David R

    2012-01-01

    REA's Problem Solvers is a series of useful, practical, and informative study guides. Each title in the series is complete step-by-step solution guide. The Differential Equations Problem Solver enables students to solve difficult problems by showing them step-by-step solutions to Differential Equations problems. The Problem Solvers cover material ranging from the elementary to the advanced and make excellent review books and textbook companions. They're perfect for undergraduate and graduate studies.The Differential Equations Problem Solver is the perfect resource for any class, any exam, and

  2. Users are problem solvers!

    NARCIS (Netherlands)

    Brouwer-Janse, M.D.

    1991-01-01

    Most formal problem-solving studies use verbal protocol and observational data of problem solvers working on a task. In user-centred product-design projects, observational studies of users are frequently used too. In the latter case, however, systematic control of conditions, indepth analysis and

  3. Electric circuits problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

    Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of electric circuits currently av

  4. Advanced calculus problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

    Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of advanced calculus currently av

  5. Sherlock Holmes, Master Problem Solver.

    Science.gov (United States)

    Ballew, Hunter

    1994-01-01

    Shows the connections between Sherlock Holmes's investigative methods and mathematical problem solving, including observations, characteristics of the problem solver, importance of data, questioning the obvious, learning from experience, learning from errors, and indirect proof. (MKR)

  6. Modern solvers for Helmholtz problems

    CERN Document Server

    Tang, Jok; Vuik, Kees

    2017-01-01

    This edited volume offers a state of the art overview of fast and robust solvers for the Helmholtz equation. The book consists of three parts: new developments and analysis in Helmholtz solvers, practical methods and implementations of Helmholtz solvers, and industrial applications. The Helmholtz equation appears in a wide range of science and engineering disciplines in which wave propagation is modeled. Examples are: seismic inversion, ultrasone medical imaging, sonar detection of submarines, waves in harbours and many more. The partial differential equation looks simple but is hard to solve. In order to approximate the solution of the problem numerical methods are needed. First a discretization is done. Various methods can be used: (high order) Finite Difference Method, Finite Element Method, Discontinuous Galerkin Method and Boundary Element Method. The resulting linear system is large, where the size of the problem increases with increasing frequency. Due to higher frequencies the seismic images need to b...

  7. The Complete Problem Solver.

    Science.gov (United States)

    Hayes, John R.

    This book, designed for a college course on general problem-solving skills, focuses on skills that can be used by anyone in solving problems that occur in everyday life. Part I considers theory and practice: understanding problems, search, and protocol analysis. Part II discusses memory and knowledge acquisition: the structure of human memory,…

  8. Creativity for Problem Solvers

    DEFF Research Database (Denmark)

    Vidal, Rene Victor Valqui

    2009-01-01

    This paper presents some modern and interdisciplinary concepts about creativity and creative processes specially related to problem solving. Central publications related to the theme are briefly reviewed. Creative tools and approaches suitable to support problem solving are also presented. Finally......, the paper outlines the author’s experiences using creative tools and approaches to: Facilitation of problem solving processes, strategy development in organisations, design of optimisation systems for large scale and complex logistic systems, and creative design of software optimisation for complex non...

  9. Test set for initial value problem solvers

    NARCIS (Netherlands)

    W.M. Lioen (Walter); J.J.B. de Swart (Jacques)

    1998-01-01

    textabstractThe CWI test set for IVP solvers presents a collection of Initial Value Problems to test solvers for implicit differential equations. This test set can both decrease the effort for the code developer to test his software in a reliable way, and cross the bridge between the application

  10. Problem Solvers' Conceptions about Osmosis.

    Science.gov (United States)

    Zuckerman, June T.

    1994-01-01

    Discusses the scheme and findings of a study designed to identify the conceptual knowledge used by high school students to solve a significant problem related to osmosis. Useful tips are provided to teachers to aid students in developing constructs that maximize understanding. (ZWH)

  11. From 'troublemakers' to problem solvers

    DEFF Research Database (Denmark)

    Frandsen, Martin Severin; Pfeiffer Petersen, Lene

    2012-01-01

    in a disadvantaged neighbourhood in the suburbs of Copenhagen, designed and constructed colourful and imaginative dustbins to handle problems with local littering. The project was successful in creating an increased local awareness of waste management and reducing the amount of litter. However, the more important...

  12. Fostering Creative Problem Solvers in Higher Education

    DEFF Research Database (Denmark)

    Zhou, Chunfang

    2016-01-01

    to meet such challenges. This chapter aims to illustrate how to understand: 1) complexity as the nature of professional practice; 2) creative problem solving as the core skill in professional practice; 3) creativity as interplay between persons and their environment; 4) higher education as the context......Recent studies have emphasized issues of social emergence based on thinking of societies as complex systems. The complexity of professional practice has been recognized as the root of challenges for higher education. To foster creative problem solvers is a key response of higher education in order...... of fostering creative problem solvers; and 5) some innovative strategies such as Problem-Based Learning (PBL) and building a learning environment by Information Communication Technology (ICT) as potential strategies of creativity development. Accordingly, this chapter contributes to bridge the complexity...

  13. Differences in the Processes of Solving Physics Problems between Good Physics Problem Solvers and Poor Physics Problem Solvers.

    Science.gov (United States)

    Finegold, M.; Mass, R.

    1985-01-01

    Good problem solvers and poor problem solvers in advanced physics (N=8) were significantly different in their ability in translating, planning, and physical reasoning, as well as in problem solving time; no differences in reliance on algebraic solutions and checking problems were noted. Implications for physics teaching are discussed. (DH)

  14. Aleph Field Solver Challenge Problem Results Summary

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, Russell [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Moore, Stan Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Aleph models continuum electrostatic and steady and transient thermal fields using a finite-element method. Much work has gone into expanding the core solver capability to support enriched modeling consisting of multiple interacting fields, special boundary conditions and two-way interfacial coupling with particles modeled using Aleph's complementary particle-in-cell capability. This report provides quantitative evidence for correct implementation of Aleph's field solver via order- of-convergence assessments on a collection of problems of increasing complexity. It is intended to provide Aleph with a pedigree and to establish a basis for confidence in results for more challenging problems important to Sandia's mission that Aleph was specifically designed to address.

  15. Metaheuristics progress as real problem solvers

    CERN Document Server

    Nonobe, Koji; Yagiura, Mutsunori

    2005-01-01

    Metaheuristics: Progress as Real Problem Solvers is a peer-reviewed volume of eighteen current, cutting-edge papers by leading researchers in the field. Included are an invited paper by F. Glover and G. Kochenberger, which discusses the concept of Metaheuristic agent processes, and a tutorial paper by M.G.C. Resende and C.C. Ribeiro discussing GRASP with path-relinking. Other papers discuss problem-solving approaches to timetabling, automated planograms, elevators, space allocation, shift design, cutting stock, flexible shop scheduling, colorectal cancer and cartography. A final group of methodology papers clarify various aspects of Metaheuristics from the computational view point.

  16. Experiences with linear solvers for oil reservoir simulation problems

    Energy Technology Data Exchange (ETDEWEB)

    Joubert, W.; Janardhan, R. [Los Alamos National Lab., NM (United States); Biswas, D.; Carey, G.

    1996-12-31

    This talk will focus on practical experiences with iterative linear solver algorithms used in conjunction with Amoco Production Company`s Falcon oil reservoir simulation code. The goal of this study is to determine the best linear solver algorithms for these types of problems. The results of numerical experiments will be presented.

  17. Integrating Problem Solvers from Analogous Markets in New Product Ideation

    DEFF Research Database (Denmark)

    Franke, Nikolaus; Poetz, Marion; Schreier, Martin

    2014-01-01

    Who provides better inputs to new product ideation tasks, problem solvers with expertise in the area for which new products are to be developed or problem solvers from “analogous” markets that are distant but share an analogous problem or need? Conventional wisdom appears to suggest that target...... market expertise is indispensable, which is why most managers searching for new ideas tend to stay within their own market context even when they do search outside their firms' boundaries. However, in a unique symmetric experiment that isolates the effect of market origin, we find evidence...... for the opposite: Although solutions provided by problem solvers from analogous markets show lower potential for immediate use, they demonstrate substantially higher levels of novelty. Also, compared to established novelty drivers, this effect appears highly relevant from a managerial perspective: we find...

  18. From Answer-Getters to Problem Solvers

    Science.gov (United States)

    Flynn, Mike

    2017-01-01

    In some math classrooms, students are taught to follow and memorize procedures to arrive at the correct solution to problems. In this article, author Mike Flynn suggests a way to move beyond answer-getting to true problem solving. He describes an instructional approach called three-act tasks in which students solve an engaging math problem in…

  19. How to become a good problem solver.

    Science.gov (United States)

    Gurden, Dean

    2016-09-14

    Nurses face many problems in the workplace on a daily basis, so the ability to solve or overcome them is essential to the job. If you are a nursing student and feel you lack problem-solving skills, what kind of help can you get?

  20. Menu-Driven Solver Of Linear-Programming Problems

    Science.gov (United States)

    Viterna, L. A.; Ferencz, D.

    1992-01-01

    Program assists inexperienced user in formulating linear-programming problems. A Linear Program Solver (ALPS) computer program is full-featured LP analysis program. Solves plain linear-programming problems as well as more-complicated mixed-integer and pure-integer programs. Also contains efficient technique for solution of purely binary linear-programming problems. Written entirely in IBM's APL2/PC software, Version 1.01. Packed program contains licensed material, property of IBM (copyright 1988, all rights reserved).

  1. SolveDB: Integrating Optimization Problem Solvers Into SQL Databases

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Pedersen, Torben Bach

    2016-01-01

    for optimization problems, (2) an extensible infrastructure for integrating different solvers, and (3) query optimization techniques to achieve the best execution performance and/or result quality. Extensive experiments with the PostgreSQL-based implementation show that SolveDB is a versatile tool offering much...

  2. Scalable Adaptive Multilevel Solvers for Multiphysics Problems

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jinchao [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics

    2014-11-26

    In this project, we carried out many studies on adaptive and parallel multilevel methods for numerical modeling for various applications, including Magnetohydrodynamics (MHD) and complex fluids. We have made significant efforts and advances in adaptive multilevel methods of the multiphysics problems: multigrid methods, adaptive finite element methods, and applications.

  3. Problem Solvers: Solutions--Playing Basketball

    Science.gov (United States)

    Smith, Jeffrey

    2014-01-01

    In this article, fourth grade Upper Allen Elementary School (Mechanicsburg, Pennsylvania) teacher Jeffrey Smith describes his exploration of the Playing Basketball activity. Herein he describes how he found the problem to be an effective way to review concepts associated with the measurement of elapsed time with his students. Additionally, it…

  4. The Human Mind As General Problem Solver

    Science.gov (United States)

    Gurr, Henry

    2011-10-01

    Since leaving U Cal Irvine Neutrino Research, I have been a University Physics Teacher, and an Informal Researcher Of Human Functionality. My talk will share what I discovered about the best ways to learn, many of which are regularities that are to be expected from the Neuronal Network Properties announced in the publications of physicist John Joseph Hopfield. Hopfield's Model of mammalian brain-body, provides solid instructive understanding of how best Learn, Solve Problems, Live! With it we understand many otherwise puzzling features of our intellect! Examples Why 1) Analogies and metaphors powerful in class instruction, ditto poems. 2) Best learning done in physical (Hands-On) situations with tight immediate dynamical feedback such as seen in learning to ride bike, drive car, speak language, etc. 3) Some of the best learning happens in seeming random exploration, bump around, trial and error. 4) Scientific discoveries happen, with no apparent effort, at odd moments. 5) Important discoveries DEPEND on considerable frustrating effort, then Flash of Insight AHA EURIKA.

  5. Parallel Auxiliary Space AMG Solver for $H(div)$ Problems

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, Tzanio V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2012-12-18

    We present a family of scalable preconditioners for matrices arising in the discretization of $H(div)$ problems using the lowest order Raviart--Thomas finite elements. Our approach belongs to the class of “auxiliary space''--based methods and requires only the finite element stiffness matrix plus some minimal additional discretization information about the topology and orientation of mesh entities. Also, we provide a detailed algebraic description of the theory, parallel implementation, and different variants of this parallel auxiliary space divergence solver (ADS) and discuss its relations to the Hiptmair--Xu (HX) auxiliary space decomposition of $H(div)$ [SIAM J. Numer. Anal., 45 (2007), pp. 2483--2509] and to the auxiliary space Maxwell solver AMS [J. Comput. Math., 27 (2009), pp. 604--623]. Finally, an extensive set of numerical experiments demonstrates the robustness and scalability of our implementation on large-scale $H(div)$ problems with large jumps in the material coefficients.

  6. Parallel Solver for H(div) Problems Using Hybridization and AMG

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chak S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-15

    In this paper, a scalable parallel solver is proposed for H(div) problems discretized by arbitrary order finite elements on general unstructured meshes. The solver is based on hybridization and algebraic multigrid (AMG). Unlike some previously studied H(div) solvers, the hybridization solver does not require discrete curl and gradient operators as additional input from the user. Instead, only some element information is needed in the construction of the solver. The hybridization results in a H1-equivalent symmetric positive definite system, which is then rescaled and solved by AMG solvers designed for H1 problems. Weak and strong scaling of the method are examined through several numerical tests. Our numerical results show that the proposed solver provides a promising alternative to ADS, a state-of-the-art solver [12], for H(div) problems. In fact, it outperforms ADS for higher order elements.

  7. Mathematical Tasks without Words and Word Problems: Perceptions of Reluctant Problem Solvers

    Science.gov (United States)

    Holbert, Sydney Margaret

    2013-01-01

    This qualitative research study used a multiple, holistic case study approach (Yin, 2009) to explore the perceptions of reluctant problem solvers related to mathematical tasks without words and word problems. Participants were given a choice of working a mathematical task without words or a word problem during four problem-solving sessions. Data…

  8. Teaching problem solving: Don't forget the problem solver(s)

    Science.gov (United States)

    Ranade, Saidas M.; Corrales, Angela

    2013-05-01

    The importance of intrapersonal and interpersonal intelligences has long been known but educators have debated whether to and how to incorporate those topics in an already crowded engineering curriculum. In 2010, the authors used the classroom as a laboratory to observe the usefulness of including selected case studies and exercises from the fields of neurology, artificial intelligence, cognitive sciences and social psychology in a new problem-solving course. To further validate their initial findings, in 2012, the authors conducted an online survey of engineering students and engineers. The main conclusion is that engineering students will benefit from learning more about the impact of emotions, culture, diversity and cognitive biases when solving problems. Specifically, the work shows that an augmented problem-solving curriculum needs to include lessons on labelling emotions and cognitive biases, 'evidence-based' data on the importance of culture and diversity and additional practice on estimating conditional probability.

  9. Scalable Newton-Krylov solver for very large power flow problems

    NARCIS (Netherlands)

    Idema, R.; Lahaye, D.J.P.; Vuik, C.; Van der Sluis, L.

    2010-01-01

    The power flow problem is generally solved by the Newton-Raphson method with a sparse direct solver for the linear system of equations in each iteration. While this works fine for small power flow problems, we will show that for very large problems the direct solver is very slow and we present

  10. POWERPLAY: Training an Increasingly General Problem Solver by Continually Searching for the Simplest Still Unsolvable Problem

    Directory of Open Access Journals (Sweden)

    Jürgen eSchmidhuber

    2013-06-01

    Full Text Available Most of computer science focuses on automatically solving given computational problems. I focus on automatically inventing or discovering problems in a way inspired by the playful behavior of animals and humans, to train a more and more general problem solver from scratch in an unsupervised fashion. Consider the infinite set of all computable descriptions of tasks with possibly computable solutions. The novel algorithmic framework POWERPLAY (2011 continually searches the space of possible pairs of new tasks and modifications of the current problem solver, until it finds a more powerful problem solver that provably solves all previously learned tasks plus the new one, while the unmodified predecessor does not. Wow-effects are achieved by continually making previously learned skills more efficient such that they require less time and space. New skills may (partially re-use previously learned skills. POWERPLAY's search orders candidate pairs of tasks and solver modifications by their conditional computational (time & space complexity, given the stored experience so far. The new task and its corresponding task-solving skill are those first found and validated. The computational costs of validating new tasks need not grow with task repertoire size. POWERPLAY's ongoing search for novelty keeps breaking the generalization abilities of its present solver. This is related to Goedel's sequence of increasingly powerful formal theories based on adding formerly unprovable statements to the axioms without affecting previously provable theorems. The continually increasing repertoire of problem solving procedures can be exploited by a parallel search for solutions to additional externally posed tasks. POWERPLAY may be viewed as a greedy but practical implementation of basic principles of creativity. A first experimental analysis can be found in separate papers [58, 56, 57].

  11. Parallel time domain solvers for electrically large transient scattering problems

    KAUST Repository

    Liu, Yang

    2014-09-26

    Marching on in time (MOT)-based integral equation solvers represent an increasingly appealing avenue for analyzing transient electromagnetic interactions with large and complex structures. MOT integral equation solvers for analyzing electromagnetic scattering from perfect electrically conducting objects are obtained by enforcing electric field boundary conditions and implicitly time advance electric surface current densities by iteratively solving sparse systems of equations at all time steps. Contrary to finite difference and element competitors, these solvers apply to nonlinear and multi-scale structures comprising geometrically intricate and deep sub-wavelength features residing atop electrically large platforms. Moreover, they are high-order accurate, stable in the low- and high-frequency limits, and applicable to conducting and penetrable structures represented by highly irregular meshes. This presentation reviews some recent advances in the parallel implementations of time domain integral equation solvers, specifically those that leverage multilevel plane-wave time-domain algorithm (PWTD) on modern manycore computer architectures including graphics processing units (GPUs) and distributed memory supercomputers. The GPU-based implementation achieves at least one order of magnitude speedups compared to serial implementations while the distributed parallel implementation are highly scalable to thousands of compute-nodes. A distributed parallel PWTD kernel has been adopted to solve time domain surface/volume integral equations (TDSIE/TDVIE) for analyzing transient scattering from large and complex-shaped perfectly electrically conducting (PEC)/dielectric objects involving ten million/tens of millions of spatial unknowns.

  12. VCODE, Ordinary Differential Equation Solver for Stiff and Non-Stiff Problems

    International Nuclear Information System (INIS)

    Cohen, Scott D.; Hindmarsh, Alan C.

    2001-01-01

    1 - Description of program or function: CVODE is a package written in ANSI standard C for solving initial value problems for ordinary differential equations. It solves both stiff and non stiff systems. In the stiff case, it includes a variety of options for treating the Jacobian of the system, including dense and band matrix solvers, and a preconditioned Krylov (iterative) solver. 2 - Method of solution: Integration is by Adams or BDF (Backward Differentiation Formula) methods, at user option. Corrector iteration is by functional iteration or Newton iteration. For the solution of linear systems within Newton iteration, users can select a dense solver, a band solver, a diagonal approximation, or a preconditioned Generalized Minimal Residual (GMRES) solver. In the dense and band cases, the user can supply a Jacobian approximation or let CVODE generate it internally. In the GMRES case, the pre-conditioner is user-supplied

  13. Legal problems brought about by technological progress

    International Nuclear Information System (INIS)

    1986-01-01

    In almost all sectors of public or private life, advances in the natural sciences and the progress of technology provoke changes that have to be managed by society. Our legal system is far from being left untouched by such changes, and frequently has to cope with new and complex legal problems in all fields of law. The book in hand collects eleven lectures presented within the framework of the Studium Generale at Heidelberg University, dealing with significant developments and their effects on the law, as e.g.: Risk acceptance in the wake of new technologies, in vitro fertilisation, early diagnosis of embryonic malformation, protection of animals in the context of medical research, information technologies and data protection, accidents in space and liability problems, transfrontier air pollution, protection of the environment. The legal aspects and the social aspects are discussed in detail by the lectures. Three of the contributions have been separately analysed for the database. (orig./HSCH) [de

  14. A fast direct solver for boundary value problems on locally perturbed geometries

    Science.gov (United States)

    Zhang, Yabin; Gillman, Adrianna

    2018-03-01

    Many applications including optimal design and adaptive discretization techniques involve solving several boundary value problems on geometries that are local perturbations of an original geometry. This manuscript presents a fast direct solver for boundary value problems that are recast as boundary integral equations. The idea is to write the discretized boundary integral equation on a new geometry as a low rank update to the discretized problem on the original geometry. Using the Sherman-Morrison formula, the inverse can be expressed in terms of the inverse of the original system applied to the low rank factors and the right hand side. Numerical results illustrate for problems where perturbation is localized the fast direct solver is three times faster than building a new solver from scratch.

  15. Modified and fuzzified general problem solver for the 'monkey and banana' problem, 1

    International Nuclear Information System (INIS)

    Sano, Norihide; Takahashi, Ryoichi.

    1991-01-01

    The master-and-slave control system should be extensively implemented for the in-service inspection of operating nuclear power stations or the decommission of retired plants. The performance of this system depends on the intelligent slave. In this paper the degree of intelligence is approximated by the given amount of prior knowledge or suggestions. This paper aims at improving the general problem solver (GPS) by incorporating the learning process in order to solve the puzzle of the 'monkey and banana'. The monkey in this puzzle may be a reasonable alternative to represent the intelligent slave. Also, this paper deals with fuzzified problem solving since the master's command is not always crisp to the slave. (author)

  16. Modified and fuzzified general problem solver for 'monkey and banana' problem

    International Nuclear Information System (INIS)

    Sano, Norihide; Takahashi, Ryoichi.

    1994-01-01

    Automatic operation is important for the in-service inspection of nuclear power stations of the decommission of retired plants. Master and slave control will be introduced for work-robot control. It is desirable that the slave possess problem-solving capabilities. In this paper we assume that the slave incorporates the general problem solver (GPS) algorithm. In view of having solved the 'monkey and banana' problem, the slave system is regarded as reasonable alternative which incorporates the capability of problem-solving. Basically, the GPS solves a problem by reducing the difference between the initial state and goal state, and hence the performance of GPS depends on selection of the difference to be reduced. The conventional GPS is given the order of importance of the differences in advance. In this study, the GPS was improved by making use of the rules which determine the order. When several choices are available for the given difference, a fuzzified decision to determine the necessary action is made, as demonstrated in this paper. (author)

  17. Modified and fuzzified general problem solver for 'monkey and banana' problem, 2

    International Nuclear Information System (INIS)

    Sano, Norihide; Takahashi, Ryoichi.

    1991-01-01

    The automatic operation is important for the in-service inspection of the operating nuclear power station or the decommission of retired plants. The master and slave control will be introduced for work-robot control. It is desirable that the slave involves the capability of problem solving. This paper assumed that the slave involved the general problem solver algorithm. In view of having solved the puzzle of the 'monkey and banana', the slave system is regarded as the reasonable alternative which incorporates the capability of problem solving. Basically, the GPS solves a problem by reducing the difference between an initial state and a goal state, and hence the performance of GPS depends on selecting the difference to be reduced. The usual GPS is given in advance the ordering which indicates the importance of the differences. In this paper, the GPS was improved by making use of the rules which decide the order. When several choices are found on the given difference, the fuzzified decision to determine the action is demonstrated in this paper. (author)

  18. A multilevel in space and energy solver for multigroup diffusion eigenvalue problems

    Directory of Open Access Journals (Sweden)

    Ben C. Yee

    2017-09-01

    Full Text Available In this paper, we present a new multilevel in space and energy diffusion (MSED method for solving multigroup diffusion eigenvalue problems. The MSED method can be described as a PI scheme with three additional features: (1 a grey (one-group diffusion equation used to efficiently converge the fission source and eigenvalue, (2 a space-dependent Wielandt shift technique used to reduce the number of PIs required, and (3 a multigrid-in-space linear solver for the linear solves required by each PI step. In MSED, the convergence of the solution of the multigroup diffusion eigenvalue problem is accelerated by performing work on lower-order equations with only one group and/or coarser spatial grids. Results from several Fourier analyses and a one-dimensional test code are provided to verify the efficiency of the MSED method and to justify the incorporation of the grey diffusion equation and the multigrid linear solver. These results highlight the potential efficiency of the MSED method as a solver for multidimensional multigroup diffusion eigenvalue problems, and they serve as a proof of principle for future work. Our ultimate goal is to implement the MSED method as an efficient solver for the two-dimensional/three-dimensional coarse mesh finite difference diffusion system in the Michigan parallel characteristics transport code. The work in this paper represents a necessary step towards that goal.

  19. Fourier-Accelerated Nodal Solvers (FANS) for homogenization problems

    Science.gov (United States)

    Leuschner, Matthias; Fritzen, Felix

    2017-11-01

    Fourier-based homogenization schemes are useful to analyze heterogeneous microstructures represented by 2D or 3D image data. These iterative schemes involve discrete periodic convolutions with global ansatz functions (mostly fundamental solutions). The convolutions are efficiently computed using the fast Fourier transform. FANS operates on nodal variables on regular grids and converges to finite element solutions. Compared to established Fourier-based methods, the number of convolutions is reduced by FANS. Additionally, fast iterations are possible by assembling the stiffness matrix. Due to the related memory requirement, the method is best suited for medium-sized problems. A comparative study involving established Fourier-based homogenization schemes is conducted for a thermal benchmark problem with a closed-form solution. Detailed technical and algorithmic descriptions are given for all methods considered in the comparison. Furthermore, many numerical examples focusing on convergence properties for both thermal and mechanical problems, including also plasticity, are presented.

  20. Legal problems of nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Rossnagel, A.

    1987-01-01

    The contributions in this book are intended to exemplify the legal situation in connection with the reprocessing of spent nuclear fuel from the point of view of constitutional law, administrative law, and international law. Outline solutions are presented with regard to ensuring health, personal freedom, democratic rights and other rights, and are discussed. The author Rossnagel investigates whether the principle of essential matter can guarantee a parliamentary prerogative concerning this field of large-scale technology. The author Schmidt shows that there is no legal obligation of commitment to a reprocessing technology that would exclude research for or application of a less hazardous technology. The contribution by Baumann explains the problems presented by a technology not yet developed to maturity with regard to the outline approval of the technological concept, which is a prerequisite of any partial licence to be issued. The final contribution by Guendling investigates the duties under international law, as for instance transfrontier information, consultation, and legal protection, and how these duties can be better put into practice in order to comply the seriousness of the hazards involved in nuclear fuel reprocessing. (orig./HP) [de

  1. Implicit solvers for large-scale nonlinear problems

    International Nuclear Information System (INIS)

    Keyes, David E; Reynolds, Daniel R; Woodward, Carol S

    2006-01-01

    Computational scientists are grappling with increasingly complex, multi-rate applications that couple such physical phenomena as fluid dynamics, electromagnetics, radiation transport, chemical and nuclear reactions, and wave and material propagation in inhomogeneous media. Parallel computers with large storage capacities are paving the way for high-resolution simulations of coupled problems; however, hardware improvements alone will not prove enough to enable simulations based on brute-force algorithmic approaches. To accurately capture nonlinear couplings between dynamically relevant phenomena, often while stepping over rapid adjustments to quasi-equilibria, simulation scientists are increasingly turning to implicit formulations that require a discrete nonlinear system to be solved for each time step or steady state solution. Recent advances in iterative methods have made fully implicit formulations a viable option for solution of these large-scale problems. In this paper, we overview one of the most effective iterative methods, Newton-Krylov, for nonlinear systems and point to software packages with its implementation. We illustrate the method with an example from magnetically confined plasma fusion and briefly survey other areas in which implicit methods have bestowed important advantages, such as allowing high-order temporal integration and providing a pathway to sensitivity analyses and optimization. Lastly, we overview algorithm extensions under development motivated by current SciDAC applications

  2. PowerPlay: Training an Increasingly General Problem Solver by Continually Searching for the Simplest Still Unsolvable Problem.

    Science.gov (United States)

    Schmidhuber, Jürgen

    2013-01-01

    Most of computer science focuses on automatically solving given computational problems. I focus on automatically inventing or discovering problems in a way inspired by the playful behavior of animals and humans, to train a more and more general problem solver from scratch in an unsupervised fashion. Consider the infinite set of all computable descriptions of tasks with possibly computable solutions. Given a general problem-solving architecture, at any given time, the novel algorithmic framework PowerPlay (Schmidhuber, 2011) searches the space of possible pairs of new tasks and modifications of the current problem solver, until it finds a more powerful problem solver that provably solves all previously learned tasks plus the new one, while the unmodified predecessor does not. Newly invented tasks may require to achieve a wow-effect by making previously learned skills more efficient such that they require less time and space. New skills may (partially) re-use previously learned skills. The greedy search of typical PowerPlay variants uses time-optimal program search to order candidate pairs of tasks and solver modifications by their conditional computational (time and space) complexity, given the stored experience so far. The new task and its corresponding task-solving skill are those first found and validated. This biases the search toward pairs that can be described compactly and validated quickly. The computational costs of validating new tasks need not grow with task repertoire size. Standard problem solver architectures of personal computers or neural networks tend to generalize by solving numerous tasks outside the self-invented training set; PowerPlay's ongoing search for novelty keeps breaking the generalization abilities of its present solver. This is related to Gödel's sequence of increasingly powerful formal theories based on adding formerly unprovable statements to the axioms without affecting previously provable theorems. The continually increasing

  3. Applications of an implicit HLLC-based Godunov solver for steady state hypersonic problems

    International Nuclear Information System (INIS)

    Link, R.A.; Sharman, B.

    2005-01-01

    Over the past few years, there has been considerable activity developing research vehicles for studying hypersonic propulsion. Successful launches of the Australian Hyshot and the US Hyper-X vehicles have added a significant amount of flight test data to a field that had previously been limited to numerical simulation. A number of approaches have been proposed for hypersonics propulsion, including attached detonation wave, supersonics combustion, and shock induced combustion. Due to the high cost of developing flight hardware, CFD simulations will continue to be a key tool for investigating the feasibility of these concepts. Capturing the interactions of the vehicle body with the boundary layer and chemical reactions pushes the limits of available modelling tools and computer hardware. Explicit formulations are extremely slow in converging to a steady state; therefore, the use of implicit methods are warranted. An implicit LLC-based Godunov solver has been developed at Martec in collaboration with DRDC Valcartier to solve hypersonic problems with a minimum of CPU time and RAM storage. The solver, Chinook Implicit, is based upon the implicit formulation adopted by Batten et. al. The solver is based on a point implicit Gauss-Seidel method for unstructured grids, and includes fully implicit boundary conditions. Preliminary results for small and large scale inviscid hypersonics problems will be presented. (author)

  4. Cartesian Mesh Linearized Euler Equations Solver for Aeroacoustic Problems around Full Aircraft

    Directory of Open Access Journals (Sweden)

    Yuma Fukushima

    2015-01-01

    Full Text Available The linearized Euler equations (LEEs solver for aeroacoustic problems has been developed on block-structured Cartesian mesh to address complex geometry. Taking advantage of the benefits of Cartesian mesh, we employ high-order schemes for spatial derivatives and for time integration. On the other hand, the difficulty of accommodating curved wall boundaries is addressed by the immersed boundary method. The resulting LEEs solver is robust to complex geometry and numerically efficient in a parallel environment. The accuracy and effectiveness of the present solver are validated by one-dimensional and three-dimensional test cases. Acoustic scattering around a sphere and noise propagation from the JT15D nacelle are computed. The results show good agreement with analytical, computational, and experimental results. Finally, noise propagation around fuselage-wing-nacelle configurations is computed as a practical example. The results show that the sound pressure level below the over-the-wing nacelle (OWN configuration is much lower than that of the conventional DLR-F6 aircraft configuration due to the shielding effect of the OWN configuration.

  5. Solving very large scattering problems using a parallel PWTD-enhanced surface integral equation solver

    KAUST Repository

    Liu, Yang

    2013-07-01

    The computational complexity and memory requirements of multilevel plane wave time domain (PWTD)-accelerated marching-on-in-time (MOT)-based surface integral equation (SIE) solvers scale as O(NtNs(log 2)Ns) and O(Ns 1.5); here N t and Ns denote numbers of temporal and spatial basis functions discretizing the current [Shanker et al., IEEE Trans. Antennas Propag., 51, 628-641, 2003]. In the past, serial versions of these solvers have been successfully applied to the analysis of scattering from perfect electrically conducting as well as homogeneous penetrable targets involving up to Ns ≈ 0.5 × 106 and Nt ≈ 10 3. To solve larger problems, parallel PWTD-enhanced MOT solvers are called for. Even though a simple parallelization strategy was demonstrated in the context of electromagnetic compatibility analysis [M. Lu et al., in Proc. IEEE Int. Symp. AP-S, 4, 4212-4215, 2004], by and large, progress in this area has been slow. The lack of progress can be attributed wholesale to difficulties associated with the construction of a scalable PWTD kernel. © 2013 IEEE.

  6. The Problem Solver and The Artisan Designer: Strategies for Utilizing Design Idea Archives

    DEFF Research Database (Denmark)

    Inie, Nanna; Endo, Allison; Dow, Steven

    2018-01-01

    This paper presents the results of an extensive qualitative study investigating how professional designers utilize personal idea archives. While we know that designers archive creative ideas in different formats and on different platforms, we know little about if and how designers utilize...... these idea archives in their daily practice. Through a series of interviews (n=20) and walkthroughs of design idea archives, we identified two archetypal strategies. The Problem Solver is concerned with the task at hand, keeps relevant ideas around, and discards them when the ideas have served their purpose...

  7. A fast Linear Complementarity Problem (LCP) solver for separating fluid-solid wall boundary Conditions

    DEFF Research Database (Denmark)

    Andersen, Michael; Abel, Sarah Maria Niebe; Erleben, Kenny

    2017-01-01

    We address the task of computing solutions for a separating fluid-solid wall boundary condition model. We present an embarrassingly parallel, easy to implement, fluid LCP solver.We are able to use greater domain sizes than previous works have shown, due to our new solver. The solver exploits matr...

  8. Composing problem solvers for simulation experimentation: a case study on steady state estimation.

    Science.gov (United States)

    Leye, Stefan; Ewald, Roland; Uhrmacher, Adelinde M

    2014-01-01

    Simulation experiments involve various sub-tasks, e.g., parameter optimization, simulation execution, or output data analysis. Many algorithms can be applied to such tasks, but their performance depends on the given problem. Steady state estimation in systems biology is a typical example for this: several estimators have been proposed, each with its own (dis-)advantages. Experimenters, therefore, must choose from the available options, even though they may not be aware of the consequences. To support those users, we propose a general scheme to aggregate such algorithms to so-called synthetic problem solvers, which exploit algorithm differences to improve overall performance. Our approach subsumes various aggregation mechanisms, supports automatic configuration from training data (e.g., via ensemble learning or portfolio selection), and extends the plugin system of the open source modeling and simulation framework James II. We show the benefits of our approach by applying it to steady state estimation for cell-biological models.

  9. GASPACHO: a generic automatic solver using proximal algorithms for convex huge optimization problems

    Science.gov (United States)

    Goossens, Bart; Luong, Hiêp; Philips, Wilfried

    2017-08-01

    Many inverse problems (e.g., demosaicking, deblurring, denoising, image fusion, HDR synthesis) share various similarities: degradation operators are often modeled by a specific data fitting function while image prior knowledge (e.g., sparsity) is incorporated by additional regularization terms. In this paper, we investigate automatic algorithmic techniques for evaluating proximal operators. These algorithmic techniques also enable efficient calculation of adjoints from linear operators in a general matrix-free setting. In particular, we study the simultaneous-direction method of multipliers (SDMM) and the parallel proximal algorithm (PPXA) solvers and show that the automatically derived implementations are well suited for both single-GPU and multi-GPU processing. We demonstrate this approach for an Electron Microscopy (EM) deconvolution problem.

  10. Telescopic Hybrid Fast Solver for 3D Elliptic Problems with Point Singularities

    KAUST Repository

    Paszyńska, Anna; Jopek, Konrad; Banaś, Krzysztof; Paszyński, Maciej; Gurgul, Piotr; Lenerth, Andrew; Nguyen, Donald; Pingali, Keshav; Dalcind, Lisandro; Calo, Victor M.

    2015-01-01

    This paper describes a telescopic solver for two dimensional h adaptive grids with point singularities. The input for the telescopic solver is an h refined two dimensional computational mesh with rectangular finite elements. The candidates for point singularities are first localized over the mesh by using a greedy algorithm. Having the candidates for point singularities, we execute either a direct solver, that performs multiple refinements towards selected point singularities and executes a parallel direct solver algorithm which has logarithmic cost with respect to refinement level. The direct solvers executed over each candidate for point singularity return local Schur complement matrices that can be merged together and submitted to iterative solver. In this paper we utilize a parallel multi-thread GALOIS solver as a direct solver. We use Incomplete LU Preconditioned Conjugated Gradients (ILUPCG) as an iterative solver. We also show that elimination of point singularities from the refined mesh reduces significantly the number of iterations to be performed by the ILUPCG iterative solver.

  11. Telescopic Hybrid Fast Solver for 3D Elliptic Problems with Point Singularities

    KAUST Repository

    Paszyńska, Anna

    2015-06-01

    This paper describes a telescopic solver for two dimensional h adaptive grids with point singularities. The input for the telescopic solver is an h refined two dimensional computational mesh with rectangular finite elements. The candidates for point singularities are first localized over the mesh by using a greedy algorithm. Having the candidates for point singularities, we execute either a direct solver, that performs multiple refinements towards selected point singularities and executes a parallel direct solver algorithm which has logarithmic cost with respect to refinement level. The direct solvers executed over each candidate for point singularity return local Schur complement matrices that can be merged together and submitted to iterative solver. In this paper we utilize a parallel multi-thread GALOIS solver as a direct solver. We use Incomplete LU Preconditioned Conjugated Gradients (ILUPCG) as an iterative solver. We also show that elimination of point singularities from the refined mesh reduces significantly the number of iterations to be performed by the ILUPCG iterative solver.

  12. On the computational efficiency of isogeometric methods for smooth elliptic problems using direct solvers

    KAUST Repository

    Collier, Nathan; Dalcin, Lisandro; Calo, Victor M.

    2014-01-01

    SUMMARY: We compare the computational efficiency of isogeometric Galerkin and collocation methods for partial differential equations in the asymptotic regime. We define a metric to identify when numerical experiments have reached this regime. We then apply these ideas to analyze the performance of different isogeometric discretizations, which encompass C0 finite element spaces and higher-continuous spaces. We derive convergence and cost estimates in terms of the total number of degrees of freedom and then perform an asymptotic numerical comparison of the efficiency of these methods applied to an elliptic problem. These estimates are derived assuming that the underlying solution is smooth, the full Gauss quadrature is used in each non-zero knot span and the numerical solution of the discrete system is found using a direct multi-frontal solver. We conclude that under the assumptions detailed in this paper, higher-continuous basis functions provide marginal benefits.

  13. High-resolution coupled physics solvers for analysing fine-scale nuclear reactor design problems

    Science.gov (United States)

    Mahadevan, Vijay S.; Merzari, Elia; Tautges, Timothy; Jain, Rajeev; Obabko, Aleksandr; Smith, Michael; Fischer, Paul

    2014-01-01

    An integrated multi-physics simulation capability for the design and analysis of current and future nuclear reactor models is being investigated, to tightly couple neutron transport and thermal-hydraulics physics under the SHARP framework. Over several years, high-fidelity, validated mono-physics solvers with proven scalability on petascale architectures have been developed independently. Based on a unified component-based architecture, these existing codes can be coupled with a mesh-data backplane and a flexible coupling-strategy-based driver suite to produce a viable tool for analysts. The goal of the SHARP framework is to perform fully resolved coupled physics analysis of a reactor on heterogeneous geometry, in order to reduce the overall numerical uncertainty while leveraging available computational resources. The coupling methodology and software interfaces of the framework are presented, along with verification studies on two representative fast sodium-cooled reactor demonstration problems to prove the usability of the SHARP framework. PMID:24982250

  14. On the computational efficiency of isogeometric methods for smooth elliptic problems using direct solvers

    KAUST Repository

    Collier, Nathan

    2014-09-17

    SUMMARY: We compare the computational efficiency of isogeometric Galerkin and collocation methods for partial differential equations in the asymptotic regime. We define a metric to identify when numerical experiments have reached this regime. We then apply these ideas to analyze the performance of different isogeometric discretizations, which encompass C0 finite element spaces and higher-continuous spaces. We derive convergence and cost estimates in terms of the total number of degrees of freedom and then perform an asymptotic numerical comparison of the efficiency of these methods applied to an elliptic problem. These estimates are derived assuming that the underlying solution is smooth, the full Gauss quadrature is used in each non-zero knot span and the numerical solution of the discrete system is found using a direct multi-frontal solver. We conclude that under the assumptions detailed in this paper, higher-continuous basis functions provide marginal benefits.

  15. Corporate environment protection as a legal problem

    International Nuclear Information System (INIS)

    Kloepfer, M.

    1993-01-01

    It is discussed what legal instruments companies have for integrating environment protection into their corporate policy: Industrial self-monitoring; the environmental health officer as an instrument of corporate environment protection (environmental health officer, radiation protection officer); obligations to disclose information on corporate organisation pursuant to Article 52 a of the Federal Emmission Control Act; corporate environment protection as a general obligation of the operator. Possible ways of strengthening corporate environment protection are considered de lege ferende, e.g. the additional instruments of corporate self-monitoring laid down in the General Part of the Environmental Code, audits on environment protection, corporate environment protection through quality assurance systems. (orig.) [de

  16. Making Sense of Math: How to Help Every Student become a Mathematical Thinker and Problem Solver (ASCD Arias)

    Science.gov (United States)

    Seeley, Cathy L.

    2016-01-01

    In "Making Sense of Math," Cathy L. Seeley, former president of the National Council of Teachers of Mathematics, shares her insight into how to turn your students into flexible mathematical thinkers and problem solvers. This practical volume concentrates on the following areas: (1) Making sense of math by fostering habits of mind that…

  17. Larger groups of passerines are more efficient problem solvers in the wild

    Science.gov (United States)

    Morand-Ferron, Julie; Quinn, John L.

    2011-01-01

    Group living commonly helps organisms face challenging environmental conditions. Although a known phenomenon in humans, recent findings suggest that a benefit of group living in animals generally might be increased innovative problem-solving efficiency. This benefit has never been demonstrated in a natural context, however, and the mechanisms underlying improved efficiency are largely unknown. We examined the problem-solving performance of great and blue tits at automated devices and found that efficiency increased with flock size. This relationship held when restricting the analysis to naive individuals, demonstrating that larger groups increased innovation efficiency. In addition to this effect of naive flock size, the presence of at least one experienced bird increased the frequency of solving, and larger flocks were more likely to contain experienced birds. These findings provide empirical evidence for the “pool of competence” hypothesis in nonhuman animals. The probability of success also differed consistently between individuals, a necessary condition for the pool of competence hypothesis. Solvers had a higher probability of success when foraging with a larger number of companions and when using devices located near rather than further from protective tree cover, suggesting a role for reduced predation risk on problem-solving efficiency. In contrast to traditional group living theory, individuals joining larger flocks benefited from a higher seed intake, suggesting that group living facilitated exploitation of a novel food source through improved problem-solving efficiency. Together our results suggest that both ecological and social factors, through reduced predation risk and increased pool of competence, mediate innovation in natural populations. PMID:21930936

  18. Multidimensional Riemann problem with self-similar internal structure - part III - a multidimensional analogue of the HLLI Riemann solver for conservative hyperbolic systems

    Science.gov (United States)

    Balsara, Dinshaw S.; Nkonga, Boniface

    2017-10-01

    Just as the quality of a one-dimensional approximate Riemann solver is improved by the inclusion of internal sub-structure, the quality of a multidimensional Riemann solver is also similarly improved. Such multidimensional Riemann problems arise when multiple states come together at the vertex of a mesh. The interaction of the resulting one-dimensional Riemann problems gives rise to a strongly-interacting state. We wish to endow this strongly-interacting state with physically-motivated sub-structure. The fastest way of endowing such sub-structure consists of making a multidimensional extension of the HLLI Riemann solver for hyperbolic conservation laws. Presenting such a multidimensional analogue of the HLLI Riemann solver with linear sub-structure for use on structured meshes is the goal of this work. The multidimensional MuSIC Riemann solver documented here is universal in the sense that it can be applied to any hyperbolic conservation law. The multidimensional Riemann solver is made to be consistent with constraints that emerge naturally from the Galerkin projection of the self-similar states within the wave model. When the full eigenstructure in both directions is used in the present Riemann solver, it becomes a complete Riemann solver in a multidimensional sense. I.e., all the intermediate waves are represented in the multidimensional wave model. The work also presents, for the very first time, an important analysis of the dissipation characteristics of multidimensional Riemann solvers. The present Riemann solver results in the most efficient implementation of a multidimensional Riemann solver with sub-structure. Because it preserves stationary linearly degenerate waves, it might also help with well-balancing. Implementation-related details are presented in pointwise fashion for the one-dimensional HLLI Riemann solver as well as the multidimensional MuSIC Riemann solver.

  19. North Dakota's Centennial Quilt and Problem Solvers: Solutions: The Library Problem

    Science.gov (United States)

    Small, Marian

    2010-01-01

    Quilt investigations, such as the Barn quilt problem in the December 2008/January 2009 issue of "Teaching Children Mathematics" and its solutions in last month's issue, can spark interdisciplinary pursuits for teachers and exciting connections for the full range of elementary school students. This month, North Dakota's centennial quilt…

  20. Legal problems of energy supply within the European Communities

    International Nuclear Information System (INIS)

    Tettinger, P.J.

    1993-01-01

    The report contains two articles; the first one is titled: The Directives on Transit of Gas and Electricity - Considerations regarding the juridical limits of the realisation of the Internal Market in the Energy Sector. It has basic considerations regarding the competences of the EC-legal nature of primary and secondary Community law; it analyzes the network of competences, the legality of the Commission's Proposals concerning the Internal Energy Market and further on the possibilities of legal recourse for enterprises in the Federal Republic of Germany in case the proposal directives are adopted. The second article deals with legal problems of energy supply within the EC-especially under the aspect of British coal mining. It incluses considerations regarding a proposed European Energy Charter, recent developments in EC-law regarding electricity and natural gas, third country imports: dumping, and privatisation. (HSCH)

  1. Solving very large scattering problems using a parallel PWTD-enhanced surface integral equation solver

    KAUST Repository

    Liu, Yang; Bagci, Hakan; Michielssen, Eric

    2013-01-01

    numbers of temporal and spatial basis functions discretizing the current [Shanker et al., IEEE Trans. Antennas Propag., 51, 628-641, 2003]. In the past, serial versions of these solvers have been successfully applied to the analysis of scattering from

  2. An Extension of the Lin-Kernighan-Helsgaun TSP Solver for Constrained Traveling Salesman and Vehicle Routing Problems

    DEFF Research Database (Denmark)

    Helsgaun, Keld

    This report describes the implementation of an extension of the Lin-Kernighan-Helsgaun TSP solver for solving constrained traveling salesman and vehicle routing problems. The extension, which is called LKH-3, is able to solve a variety of well-known problems, including the sequential ordering...... problem (SOP), the traveling repairman problem (TRP), variants of the multiple travel-ing salesman problem (mTSP), as well as vehicle routing problems (VRPs) with capacity, time windows, pickup-and-delivery and distance constraints. The implementation of LKH-3 builds on the idea of transforming...... the problems into standard symmetric traveling salesman problems and handling constraints by means of penalty functions. Extensive testing on benchmark instances from the literature has shown that LKH-3 is effective. Best known solutions are often obtained, and in some cases, new best solutions are found...

  3. Experimental validation of a boundary element solver for exterior acoustic radiation problems

    NARCIS (Netherlands)

    Visser, Rene; Nilsson, A.; Boden, H.

    2003-01-01

    The relation between harmonic structural vibrations and the corresponding acoustic radiation is given by the Helmholtz integral equation (HIE). To solve this integral equation a new solver (BEMSYS) based on the boundary element method (BEM) has been implemented. This numerical tool can be used for

  4. A Matlab-based finite-difference solver for the Poisson problem with mixed Dirichlet-Neumann boundary conditions

    Science.gov (United States)

    Reimer, Ashton S.; Cheviakov, Alexei F.

    2013-03-01

    A Matlab-based finite-difference numerical solver for the Poisson equation for a rectangle and a disk in two dimensions, and a spherical domain in three dimensions, is presented. The solver is optimized for handling an arbitrary combination of Dirichlet and Neumann boundary conditions, and allows for full user control of mesh refinement. The solver routines utilize effective and parallelized sparse vector and matrix operations. Computations exhibit high speeds, numerical stability with respect to mesh size and mesh refinement, and acceptable error values even on desktop computers. Catalogue identifier: AENQ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENQ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License v3.0 No. of lines in distributed program, including test data, etc.: 102793 No. of bytes in distributed program, including test data, etc.: 369378 Distribution format: tar.gz Programming language: Matlab 2010a. Computer: PC, Macintosh. Operating system: Windows, OSX, Linux. RAM: 8 GB (8, 589, 934, 592 bytes) Classification: 4.3. Nature of problem: To solve the Poisson problem in a standard domain with “patchy surface”-type (strongly heterogeneous) Neumann/Dirichlet boundary conditions. Solution method: Finite difference with mesh refinement. Restrictions: Spherical domain in 3D; rectangular domain or a disk in 2D. Unusual features: Choice between mldivide/iterative solver for the solution of large system of linear algebraic equations that arise. Full user control of Neumann/Dirichlet boundary conditions and mesh refinement. Running time: Depending on the number of points taken and the geometry of the domain, the routine may take from less than a second to several hours to execute.

  5. Legal and institutional problems facing geothermal development in Hawaii

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-01

    The problems discussed confronting future geothermal development in Hawaii include: a seemingly insoluble mismatch of resource and market; the burgeoning land claims of the Native Hawaiian community; a potential legal challenge to the State's claim to hegemony over all of Hawaii's geothermal resources, regardless of surface ownership; resistance to any sudden, large scale influx of Mainland industry, and questionable economics for the largest potential industrial users. (MHR)

  6. A high-order integral solver for scalar problems of diffraction by screens and apertures in three-dimensional space

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Oscar P., E-mail: obruno@caltech.edu; Lintner, Stéphane K.

    2013-11-01

    We present a novel methodology for the numerical solution of problems of diffraction by infinitely thin screens in three-dimensional space. Our approach relies on new integral formulations as well as associated high-order quadrature rules. The new integral formulations involve weighted versions of the classical integral operators related to the thin-screen Dirichlet and Neumann problems as well as a generalization to the open-surface problem of the classical Calderón formulae. The high-order quadrature rules we introduce for these operators, in turn, resolve the multiple Green function and edge singularities (which occur at arbitrarily close distances from each other, and which include weakly singular as well as hypersingular kernels) and thus give rise to super-algebraically fast convergence as the discretization sizes are increased. When used in conjunction with Krylov-subspace linear algebra solvers such as GMRES, the resulting solvers produce results of high accuracy in small numbers of iterations for low and high frequencies alike. We demonstrate our methodology with a variety of numerical results for screen and aperture problems at high frequencies—including simulation of classical experiments such as the diffraction by a circular disc (featuring in particular the famous Poisson spot), evaluation of interference fringes resulting from diffraction across two nearby circular apertures, as well as solution of problems of scattering by more complex geometries consisting of multiple scatterers and cavities.

  7. Efficient CUDA Polynomial Preconditioned Conjugate Gradient Solver for Finite Element Computation of Elasticity Problems

    Directory of Open Access Journals (Sweden)

    Jianfei Zhang

    2013-01-01

    Full Text Available Graphics processing unit (GPU has obtained great success in scientific computations for its tremendous computational horsepower and very high memory bandwidth. This paper discusses the efficient way to implement polynomial preconditioned conjugate gradient solver for the finite element computation of elasticity on NVIDIA GPUs using compute unified device architecture (CUDA. Sliced block ELLPACK (SBELL format is introduced to store sparse matrix arising from finite element discretization of elasticity with fewer padding zeros than traditional ELLPACK-based formats. Polynomial preconditioning methods have been investigated both in convergence and running time. From the overall performance, the least-squares (L-S polynomial method is chosen as a preconditioner in PCG solver to finite element equations derived from elasticity for its best results on different example meshes. In the PCG solver, mixed precision algorithm is used not only to reduce the overall computational, storage requirements and bandwidth but to make full use of the capacity of the GPU devices. With SBELL format and mixed precision algorithm, the GPU-based L-S preconditioned CG can get a speedup of about 7–9 to CPU-implementation.

  8. Environmental data quality problems: ''Technical'' vs. ''legal'' defensibility

    International Nuclear Information System (INIS)

    Luker, R.S.; Brooks, M.C.; Stagg, D.D.

    1995-01-01

    Two significant aspects of environmental data quality are currently being emphasized throughout the industry as critical precursors to environmental decision making: technical integrity and legal defensibility. Because audit findings and consequent perceptions by a client often pose more questions than answers--especially with respect to the ''systemic'' nature and significance of problems based on nonstatistical, ad hoc sampling of large programs--quality assurance in environmental restoration must do more than implement traditional administrative controls. A major problem persists in achieving a consensus opinion between quality assurance and technical staff on the significance of various data problems. This case study compares and contrasts ''technical integrity'' and ''legal defensibility'', and provides performance measures developed to optimize both components in a large, complex DOE environmental restoration program. Performance measures of both administrative and technical processes are being used to ensure that conclusions drawn concerning ''systematic'' problems are not premature, and are founded on thorough, representative aspects of the program. Improved methods to reach consensus opinions on environmental decision-making are imperative and environmental data quality, the cornerstone on which the decisions are built, must be not only scientifically solid, but perceived as solid, if stakeholders are to be satisfied

  9. Algebraic multigrid preconditioning within parallel finite-element solvers for 3-D electromagnetic modelling problems in geophysics

    Science.gov (United States)

    Koldan, Jelena; Puzyrev, Vladimir; de la Puente, Josep; Houzeaux, Guillaume; Cela, José María

    2014-06-01

    We present an elaborate preconditioning scheme for Krylov subspace methods which has been developed to improve the performance and reduce the execution time of parallel node-based finite-element (FE) solvers for 3-D electromagnetic (EM) numerical modelling in exploration geophysics. This new preconditioner is based on algebraic multigrid (AMG) that uses different basic relaxation methods, such as Jacobi, symmetric successive over-relaxation (SSOR) and Gauss-Seidel, as smoothers and the wave front algorithm to create groups, which are used for a coarse-level generation. We have implemented and tested this new preconditioner within our parallel nodal FE solver for 3-D forward problems in EM induction geophysics. We have performed series of experiments for several models with different conductivity structures and characteristics to test the performance of our AMG preconditioning technique when combined with biconjugate gradient stabilized method. The results have shown that, the more challenging the problem is in terms of conductivity contrasts, ratio between the sizes of grid elements and/or frequency, the more benefit is obtained by using this preconditioner. Compared to other preconditioning schemes, such as diagonal, SSOR and truncated approximate inverse, the AMG preconditioner greatly improves the convergence of the iterative solver for all tested models. Also, when it comes to cases in which other preconditioners succeed to converge to a desired precision, AMG is able to considerably reduce the total execution time of the forward-problem code-up to an order of magnitude. Furthermore, the tests have confirmed that our AMG scheme ensures grid-independent rate of convergence, as well as improvement in convergence regardless of how big local mesh refinements are. In addition, AMG is designed to be a black-box preconditioner, which makes it easy to use and combine with different iterative methods. Finally, it has proved to be very practical and efficient in the

  10. Genesis of scientific research of legal problems of reserves

    Directory of Open Access Journals (Sweden)

    Олександр Олександрович Пономаренко

    2017-12-01

    Full Text Available The problems of the legal status of nature reserves as objects of ecological and legal commandment are considered. One of the main directions of the modern strategy of Ukraine’s environmental policy should be the implementation of international standards in the organization and protection of nature reserves as objects of the state natural reserve fund, the improvement of legislation on the nature reserve fund in accordance with the recommendations of the Pan-European Biological and Landscape Diversity Strategy (1995 on the formation of the Pan-European Ecological Network as a single spatial system of territories of European countries with the EU or partially altered landscape. All this allowed to formulate the definition of a natural reserve as a state research institution with the status of a legal entity of national importance and performs the functions of preserving in a natural state typical or unique for the given landscape zone of natural complexes with all components of their components, the study of natural processes and phenomena, the developments in them, the development of scientific principles of environmental protection, the effective use of natural resources and environmental safety, the implementation of ecological education and education of the population in the conditions of full restriction of economic activity not connected with its functioning.

  11. Legal problems concerning the export of nuclear power plants

    International Nuclear Information System (INIS)

    Pierer, Heinrich von.

    1977-01-01

    The legal problems raised by the export of nuclear power plants may be divided into three main categories: nuclear operator's liability for nuclear damage, the consequences for the supplier of the licensing requirements in the national laws of the buyer country and finally, the constraints of applying non-proliferation safeguards on export of nuclear equipment. As regards the third party liability regime in particular, the difficulties lie essentially in the insufficiency of the definition of the nuclear operator and the lack of harmonization in, or even the absence of national laws in this field. (NEA) [fr

  12. An evaluation of parallel multigrid as a solver and a preconditioner for singular perturbed problems

    Energy Technology Data Exchange (ETDEWEB)

    Oosterlee, C.W. [Inst. for Algorithms and Scientific Computing, Sankt Augustin (Germany); Washio, T. [C& C Research Lab., Sankt Augustin (Germany)

    1996-12-31

    In this paper we try to achieve h-independent convergence with preconditioned GMRES and BiCGSTAB for 2D singular perturbed equations. Three recently developed multigrid methods are adopted as a preconditioner. They are also used as solution methods in order to compare the performance of the methods as solvers and as preconditioners. Two of the multigrid methods differ only in the transfer operators. One uses standard matrix- dependent prolongation operators from. The second uses {open_quotes}upwind{close_quotes} prolongation operators, developed. Both employ the Galerkin coarse grid approximation and an alternating zebra line Gauss-Seidel smoother. The third method is based on the block LU decomposition of a matrix and on an approximate Schur complement. This multigrid variant is presented in. All three multigrid algorithms are algebraic methods.

  13. Municipal Level of Strategic Planning: Economic and Legal Problems

    Directory of Open Access Journals (Sweden)

    Evgeniy Moiseevich Bukhvald

    2016-12-01

    Full Text Available The article focuses on the need of integration of municipal government into a unified hierarchy of strategic planning in the country. The basic positions of the acting version of the Federal law no.131 “On general principles of organization of local self-government” and the Federal law no. 172 “On strategic planning” don’t provide clear legal framework for the solution of this problem. Besides, the practical integration of municipal management into a unified hierarchy of strategic planning meets serious economic obstacles, the main of which consist in the negative situation within the system of local finance, characterized by trends of deficiency, high dependence on subsidies and, as a consequence, volatility and lack of predictability in relation to any plans and programs of long-term nature. The main idea of the article is to prove the need for a systemic approach to solving tasks, related to the integration of municipal management in a unified vertical of strategic planning in the country. The essence of this approach is the combination of a number of legal innovations in the legislation on strategic planning and local government with a set of measures, aimed to strengthen the fiscal basis of Russian local self-government together with institutional ensuring of municipal planning and its interaction with the practice of strategic planning at the level of subjects of the Russian Federation.

  14. A fast algorithm for parabolic PDE-based inverse problems based on Laplace transforms and flexible Krylov solvers

    International Nuclear Information System (INIS)

    Bakhos, Tania; Saibaba, Arvind K.; Kitanidis, Peter K.

    2015-01-01

    We consider the problem of estimating parameters in large-scale weakly nonlinear inverse problems for which the underlying governing equations is a linear, time-dependent, parabolic partial differential equation. A major challenge in solving these inverse problems using Newton-type methods is the computational cost associated with solving the forward problem and with repeated construction of the Jacobian, which represents the sensitivity of the measurements to the unknown parameters. Forming the Jacobian can be prohibitively expensive because it requires repeated solutions of the forward and adjoint time-dependent parabolic partial differential equations corresponding to multiple sources and receivers. We propose an efficient method based on a Laplace transform-based exponential time integrator combined with a flexible Krylov subspace approach to solve the resulting shifted systems of equations efficiently. Our proposed solver speeds up the computation of the forward and adjoint problems, thus yielding significant speedup in total inversion time. We consider an application from Transient Hydraulic Tomography (THT), which is an imaging technique to estimate hydraulic parameters related to the subsurface from pressure measurements obtained by a series of pumping tests. The algorithms discussed are applied to a synthetic example taken from THT to demonstrate the resulting computational gains of this proposed method

  15. A fast algorithm for parabolic PDE-based inverse problems based on Laplace transforms and flexible Krylov solvers

    Energy Technology Data Exchange (ETDEWEB)

    Bakhos, Tania, E-mail: taniab@stanford.edu [Institute for Computational and Mathematical Engineering, Stanford University (United States); Saibaba, Arvind K. [Department of Electrical and Computer Engineering, Tufts University (United States); Kitanidis, Peter K. [Institute for Computational and Mathematical Engineering, Stanford University (United States); Department of Civil and Environmental Engineering, Stanford University (United States)

    2015-10-15

    We consider the problem of estimating parameters in large-scale weakly nonlinear inverse problems for which the underlying governing equations is a linear, time-dependent, parabolic partial differential equation. A major challenge in solving these inverse problems using Newton-type methods is the computational cost associated with solving the forward problem and with repeated construction of the Jacobian, which represents the sensitivity of the measurements to the unknown parameters. Forming the Jacobian can be prohibitively expensive because it requires repeated solutions of the forward and adjoint time-dependent parabolic partial differential equations corresponding to multiple sources and receivers. We propose an efficient method based on a Laplace transform-based exponential time integrator combined with a flexible Krylov subspace approach to solve the resulting shifted systems of equations efficiently. Our proposed solver speeds up the computation of the forward and adjoint problems, thus yielding significant speedup in total inversion time. We consider an application from Transient Hydraulic Tomography (THT), which is an imaging technique to estimate hydraulic parameters related to the subsurface from pressure measurements obtained by a series of pumping tests. The algorithms discussed are applied to a synthetic example taken from THT to demonstrate the resulting computational gains of this proposed method.

  16. Measuring the Level of Transfer Learning by an AP Physics Problem-Solver

    National Research Council Canada - National Science Library

    Klenk, Matthew; Forbus, Ken

    2007-01-01

    .... We approach this problem by focusing on model formulation, i.e., how to move from the unruly, broad set of concepts used in everyday life to a concise, formal vocabulary of abstractions that can be used effectively for problem solving...

  17. A Brief Study of Legal Problems in the Music Business

    Science.gov (United States)

    Shankman, Ned N.

    1977-01-01

    Individuals who go into music careers will find that they are affected and sometimes governed by particular laws and legal agreements. Provides, as an example of a legal concern of a music career, an examination of a songwriter' contract, particularly the question of sources. (Editor/RK)

  18. Problems with Legal Positivism and Tax Law

    OpenAIRE

    Bogenschneider, Bret

    2017-01-01

    This essay is a reply to the famous paper by John Gardner: Legal Positivism: 5½ Myths and the more recent paper by John Prebble: Kelsen, the Principle of Exclusion of Contradictions, and General Anti-Avoidance Rules. The reply is developed from the perspective of tax law where the respective issues are of major significance. The “5½ problems” correspond to Gardner’s arguments and are as follows: (#1) Legal Positivism centers on determining whether a tax law is “legally valid” based on its sou...

  19. Constraint-based solver for the Military unit path finding problem

    CSIR Research Space (South Africa)

    Leenen, L

    2010-04-01

    Full Text Available -based approach because it requires flexibility in modelling. The authors formulate the MUPFP as a constraint satisfaction problem and a constraint-based extension of the search algorithm. The concept demonstrator uses a provided map, for example taken from Google...

  20. 14 The Mass Media and the Problem of Understanding Legal ...

    African Journals Online (AJOL)

    User

    legal terminologies even though some are archaic or old fashioned in some ways as to .... BBC, VOA, and VON); documentary films, electronic information media, and other ..... and regulations for easy comprehension by the reading public.

  1. Community matrons as problem-solvers for people living with multi-co-morbid disease.

    Science.gov (United States)

    Randall, Sue; Thunhurst, Colin; Furze, Gill

    2016-12-02

    Working with patients in their own homes gives community matrons an advantage of seeing patients in the context of their everyday lives. This allows comprehensive assessment of need with an aim of promoting health or promoting stability for people living with chronic disease. Complex issues are resolved through problem-solving and this can result in patients being maintained in their own homes and thus in reduced unplanned hospitalisation. Data were collected from participants using semi-structured interviews and audio diaries. The sample comprised professionals: CMs (n=21), managers (n=4), former commissioners (n=2) and GPs (n=3); and patients (n=10) and their family carers (n=5). In this article, data from community matrons is discussed. Community matrons often drew on the social determinants model of health to problem solve and to create meaningful strategies that work for patients in their care. Raising awareness of the high-level skills of community matrons and promoting appreciation of the importance of a social determinants model of health is important in explaining why nurses are such a crucial element of the primary health care workforce.

  2. The problem of the legal nature of Green Certificates in the Italian legal system

    International Nuclear Information System (INIS)

    Colcelli, Valentina

    2012-01-01

    Green Certificates are usually described as negotiable instruments or commercial papers. The Italian legal system identifies Green Certificates as rights but, due to the ambiguity of the definition, their juridical nature remains uncertain. This reverberates on the functioning of the Green Certificates market and on the enforcement of the relevant norms. This paper discusses the actual legal nature of Green Certificates in Italy and concludes that they should be regarded as goods. This means that private law instruments apply in their market transactions, with consequent implications on the policy side. - Highlights: ► A definition of Green Certificates in the Italian legal system is provided. ► Green Certificates are not Credit Instruments. ► However, they may be negotiated separately from the energy they represent. ► Green Certificates are goods, which relate to new properties.

  3. [The dignity of the patient: a legal problem?].

    Science.gov (United States)

    Schultz, H

    1980-11-01

    Rules of medical ethic bid since the times of antiquity to respect the patients dignity. Today to respect the dignity of any man is a general legal rule. In the same way other rules of the traditional medical ethic became legal norms as for instance the command forbidding to do harm to someone. The law intends to limit the possibilities to exercise power. Therefore it does not compete to the doctor alone to decide that a medical treatment has to be applied. The legal base of a medical treatment lies in the consent of the patient who has been duly cleared up on his state, the necessary treatment and its risks. If it has to be decided if a doctor has given the right treatment in a special case it does not suffice to consult the general rules of the law; the circumstances of the case have to be considered as well. The doctor has to decide, according to the actual medical knowledge and the rules of his professional art what the appropriate proceeding is. Legal and medical considerations are closely connected if one judges a doctor handling a special case. If the patient consents, the doctor is not obliged to treat him, but he is entitled to do it, cases of emergency excepted. If and in what way he treats the patient has to be decided by the doctor according to medical criterias. If a patient, sound of mind, who is suffering heavily by an incurable illness asks the doctor to restrain treatment to alleviating the pains and to the absolute cares to preserve life, the doctor is bound by his patient's wish. In analogy the legal construct of "conducting business without mandate" allows the doctor to proceed in the same way if the patient who lost consciousness is not able to decide upon the treatment and whose death is inevitable and imminent if this is the only wise to respect the dignity of the patient.

  4. Legal Issues Affecting Libraries and Librarians: Employment Law, Liability and Insurance, Contracts, and Problem Patrons.

    Science.gov (United States)

    Mika, Joseph J.; Shuman, Bruce A.

    1988-01-01

    This fourth lesson in a continuing education course on legal issues affecting libraries and librarians discusses the library's rights and legal responsibilities in the areas of censorship and intellectual freedom, the Freedom of Information Act and patron privacy, problem patrons, and ethical considerations of library services. (14 references)…

  5. On the brink: how business owners experience business-related and other legal problems

    OpenAIRE

    Balmer, N. J.; Pleasence, P.

    2017-01-01

    New analysis of LAW Survey data has identified three distinct groups among business owners according to their likelihood of experiencing business-related and other types of legal problems ‒ ‘normal’, ‘highly elevated’ and ‘extreme’. As is the case with individuals, a relatively small proportion of business owners account for the bulk of problems. Targeted legal assistance services are needed for this group.

  6. Energy Security of Russia and the EU: Current Legal Problems

    Energy Technology Data Exchange (ETDEWEB)

    Seliverstov, S.

    2009-07-01

    Security of energy supply is a cornerstone of European energy policy. It receives specific mention both in the Constitution Treaty and in the Lisbon Treaty. Of course, energy and energy-generated revenues are vital for Russia as well. It is a common understanding that Russia and the EU are extremely interdependent in terms of energy. On the one hand, Russia is the strategic energy supplier to the EU as a whole; for some member states Russian supplies represent the only source of the external energy flows. On the other hand, the revenues generated from the west-bound supplies of oil and gas constitute a significant share of the overall export income and of the budget of Russian Federation. Taking the interdependency as a point of departure the present article answers the following questions: What are the differences and the similarities in the European and the Russian approaches towards security of energy supply? Is their understanding of energy security so different? What are the current legal instruments guiding interaction in this sphere? What are the actual trends that could give some indication of how the situation may develop in the future? - While the concepts of 'security of energy supplies' or of 'energy security' are theoretical in nature, the ways the concepts are understood and the legal framework for them directly influences the way they are applied in practice. (author)

  7. Energy Security of Russia and the EU: Current Legal Problems

    International Nuclear Information System (INIS)

    Seliverstov, S.

    2009-01-01

    Security of energy supply is a cornerstone of European energy policy. It receives specific mention both in the Constitution Treaty and in the Lisbon Treaty. Of course, energy and energy-generated revenues are vital for Russia as well. It is a common understanding that Russia and the EU are extremely interdependent in terms of energy. On the one hand, Russia is the strategic energy supplier to the EU as a whole; for some member states Russian supplies represent the only source of the external energy flows. On the other hand, the revenues generated from the west-bound supplies of oil and gas constitute a significant share of the overall export income and of the budget of Russian Federation. Taking the interdependency as a point of departure the present article answers the following questions: What are the differences and the similarities in the European and the Russian approaches towards security of energy supply? Is their understanding of energy security so different? What are the current legal instruments guiding interaction in this sphere? What are the actual trends that could give some indication of how the situation may develop in the future? - While the concepts of 'security of energy supplies' or of 'energy security' are theoretical in nature, the ways the concepts are understood and the legal framework for them directly influences the way they are applied in practice. (author)

  8. Risks in science and technology as a legal problem

    International Nuclear Information System (INIS)

    Wagner, H.

    1980-01-01

    The author critically examines the risk concepts and grades of risk published by other authors. In his view, scientists and engineers have primary technical competency in risk assessment. Risk evaluation as an overall process of comparing rights protected by law was reserved to the executive branch of government and to the courts of law. The residual risk to be tolerated from the legal point of view, without any provision being made for cases of damage, and the type and scope of such provisions should be limited by a comparison of rights protected by law conducted in the light of the purposes of legislation, by the principle of adequacy, and by comparative risk analyses. (HSCH) [de

  9. Legal problems of doing business with foreign energy cartels

    International Nuclear Information System (INIS)

    Sayler, R.H.

    1983-01-01

    This paper focuses on the uranium cartel - or marketing arrangement as its admitted participants styled it. The clash between US antitrust laws and cartels that fix prices is examined with particular emphasis on the uranium antitrust litigation and on a US antitrust lawsuit in which the courts rejected an attack on OPEC's price-fixing and output-limitation activities. Basic legal principles pertaining to this type of litigation are explained. Even more specialized defenses are available to complicate the litigation when foreign governments are involved with the cartel: sovereign immunity, act of state, and foreign governmental compulsion. It is concluded that antitrust litigation against a foreign cartel is not impossible, but it may be unwise in the long run if it precipitates an international reversion to protectionism. 35 references

  10. Legal problems connected with irradiated fuel reprocessing and its waste storage

    International Nuclear Information System (INIS)

    Nercy, B. de.

    1981-10-01

    In view of its nature, an irradiated nuclear fuel reprocessing operation -and the contracts implementing it between the reprocessor and the customer- raises certain difficult legal problems. This paper analyses this question from the legal viewpoint, in particular as regards nuclear fuel and material ownership and products or waste arising therefrom, as well as in the context of rules of international trade and non-proliferation standards. (NEA) [fr

  11. Legal problems inherent in the development of geopressured and geothermal resources in Louisiana. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Harrell, T.A.; Pike, R.W.; Wilkins, B.; Hill, T.M.

    1978-03-01

    The legal framework within which the geopressured resource will have to be developed in Louisiana is discussed generally. Those problems which may be created by its development within that framework are identified. Where possible, solutions are offered to those problems or at least techniques or devices are indicated which might be considered in their resolution. Finally, a compendium is assembled of those statutory or regulatory provisions which may regulate or affect the resource to the end that it might serve as a handbook for the evaluation of the legal and institutional problems which will face a prospective developer, when and if the resource development is undertaken in Louisiana. (MHR)

  12. Taking Tax Revenues Over Local Governments – Some Legal Problems

    Directory of Open Access Journals (Sweden)

    Andrzej Borodo

    2014-09-01

    Full Text Available The power of local government to take over the taxes can lead to conflicts between the local government and another local government (in whose area the property, the building, the plant, the residence and another taxable objects are located. These conflicts are not a matter of relation: the tax authority – the taxpayer. These problems concern the determination which of the local government has the power to take over the tax.

  13. High performance simplex solver

    OpenAIRE

    Huangfu, Qi

    2013-01-01

    The dual simplex method is frequently the most efficient technique for solving linear programming (LP) problems. This thesis describes an efficient implementation of the sequential dual simplex method and the design and development of two parallel dual simplex solvers. In serial, many advanced techniques for the (dual) simplex method are implemented, including sparse LU factorization, hyper-sparse linear system solution technique, efficient approaches to updating LU factors and...

  14. Politico-Legal Views of A. V. Kolchak on the Problems of the Unity of Russia

    Directory of Open Access Journals (Sweden)

    Fedor S. Sosenkov

    2017-05-01

    Full Text Available The article considers political-legal views of A. V. Kolchak on problems of ensuring state unity of Russia. Some telegrams, letters, and other documents of A.V. Kolchak and his government, other leaders of the «white movement» are analyzed.

  15. Legal and administrative problems related to the treatment and disposal of radioactive wastes

    International Nuclear Information System (INIS)

    Cornelis, J.C.

    1976-01-01

    The consequence of the rapid expansion of nuclear power programmes is that the quantity of radioactive wastes will increase in proportion. These wastes are produced during the different stages of the fuel cycle. The management of these wastes raises certain legal problems particularly regarding the methods for final storage or for sea disposal. All these management methods have an international incidence and these aspects must be studied in step with technical problems. (N.E.A.) [fr

  16. Legal problem research on surrogacy%代孕问题法律研究

    Institute of Scientific and Technical Information of China (English)

    杨晶

    2015-01-01

    Along with social progress and development, the application of surrogacy is increasingly frequent. It overturns original reproductive concept and way, at the same time through the existing legal system. Conduct legal research and legal problems of surrogacy regulation, is quite necessary.%随着社会的进步和发展,代孕这一人类辅助生殖技术在生活中的应用也日渐频繁.它颠覆了原有的生殖观念和方式,同时冲击着现有的法律制度.对代孕问题进行法律研究和法律规制,相当必要.

  17. Problems of legal regulation of credit organizations employees' work and the ways for their solution

    Directory of Open Access Journals (Sweden)

    Vereshak S.B.

    2016-09-01

    Full Text Available legal and organizational aspects of regulation of work of employees (serving banks and other credit organizations are considered. Specifics of activity of banks and other credit organizations attract need of improvement of the legislation governing the labor relations in this sphere for the purpose of reduction in compliance of established practices and standard legal support. Problems of absence of unity of terminology in the legal acts which are the cornerstone of regulation of work of employees of banks come to light; features of work of bank workers that doesn't allow to provide full protection of their labor law aren't defined; the set of shortcomings of system of compensation in the bank sphere takes place. Conclusions about need of improvement of the existing labor and banking legislation, and also local legal acts of banks for the sphere of the organization of work and its payment are drawn. Elimination of the revealed shortcomings, according to authors, will allow to strengthen legal guarantees of work of employees of banks.

  18. The problem of developing of readiness of the future legal psychologists to effective coping

    Directory of Open Access Journals (Sweden)

    Busarova O.R.

    2017-07-01

    Full Text Available The article substantiates the need to improve the readiness of the future legal psychologists to effective coping behavior in the light output at the present time in Russia professional standards governing the activities of professionals providing psychological assistance to minors, including those who are in legally relevant situations. The aim of the presented research - the identification of typical coping strategies for students of legal psychology in the educational practice and the analysis of the relationship of coping strategies with successful performance practices. Second-year students were diagnostic practice in various educational institutions, including schools and special schools for students with deviant behavior. Probationers acted as a psychologist, a holistic diagnostic problem solving - from the receipt of the request to make recommendations on the results of the survey. The method of content analysis was processed 41 report on the practice. Fixed mention of problematic situations that have caused negative emotions in the trainees, and mention of coping behavior. Revealed the typical difficulties of students and coping strategies when performing queries on psycho-diagnostics of children with behavioral problems. We found a significant positive correlation between the success of the implementation of practice tasks students with a variety mentioned in the report difficulties with the frequency of their appearance, as well as with a variety of coping strategies. The study offers methodological tools for the preparation of the future legal psychologists in diagnostic practice.

  19. Self-correcting Multigrid Solver

    International Nuclear Information System (INIS)

    Lewandowski, Jerome L.V.

    2004-01-01

    A new multigrid algorithm based on the method of self-correction for the solution of elliptic problems is described. The method exploits information contained in the residual to dynamically modify the source term (right-hand side) of the elliptic problem. It is shown that the self-correcting solver is more efficient at damping the short wavelength modes of the algebraic error than its standard equivalent. When used in conjunction with a multigrid method, the resulting solver displays an improved convergence rate with no additional computational work

  20. Does legal institutionalism rule out legal pluralism?
    Schmitt’s institutional theory and the problem of the concrete order

    Directory of Open Access Journals (Sweden)

    Mariano Croce

    2011-04-01

    Full Text Available The present paper explores the background of the institutional perspective of law that Carl Schmitt develops in On The Three Types of Juristic Thought (1934, and draws a comparison between this view and the institutional theory of Santi Romano (explicitly recalled by Schmitt. In doing so, I will shed some light on the complex relation between law and pluralism. While Schmitt portrays the law as a political means for preserving identity and excluding diversity within a homogeneous community, Romano depicts law as a form of organisation which inevitably reflects the plurality of social life.To this end, I will attend to some crucial problems of social and legal theory, such as the relation between norms and normality, the role of institutions in human life, and the way the law affects and is affected by the dynamics of its social surroundings.My final goal is to show that the law does not exclude pluralism at all, but is in itself a plural phenomenon.

  1. Training Interdisciplinary "Wicked Problem" Solvers: Applying Lessons from HERO in Community-Based Research Experiences for Undergraduates

    Science.gov (United States)

    Cantor, Alida; DeLauer, Verna; Martin, Deborah; Rogan, John

    2015-01-01

    Management of "wicked problems", messy real-world problems that defy resolution, requires thinkers who can transcend disciplinary boundaries, work collaboratively, and handle complexity and obstacles. This paper explores how educators can train undergraduates in these skills through applied community-based research, using the example of…

  2. Class and Homework Problems: The Break-Even Radius of Insulation Computed Using Excel Solver and WolframAlpha

    Science.gov (United States)

    Foley, Greg

    2014-01-01

    A problem that illustrates two ways of computing the break-even radius of insulation is outlined. The problem is suitable for students who are taking an introductory module in heat transfer or transport phenomena and who have some previous knowledge of the numerical solution of non- linear algebraic equations. The potential for computer algebra,…

  3. Legal problems surrounding the deregularisation of the power economy. Rechtliche Probleme einer Deregulierung der Elektrizitaetswirtschaft

    Energy Technology Data Exchange (ETDEWEB)

    Baur, J F; Moraing, M

    1994-01-01

    Numerous efforts, both national and international, are currently being undertaken to force competition in the power economy. Not the smallest contribution to greater competition is to come from granting third party access to the grid. The authors closely examine the different concepts that have been proposed in this controversial discussion. In doing so they place an emphasis on the implications the restructuring of the existing legal framework would have for constitutional law and here in particular for property rights. In conclusion, they find that a pool solution is hardly justifiable by constitutional law. Even an institutionalised third party access solution is considered practicable only if implemented with appropriate interim solutions. By contrast, the misuse concept already provided for by the law in force is judged to be worthy of further development. (orig.)

  4. Bargaining for Equality. A Guide to Legal and Collective Bargaining Solutions for Workplace Problems that Particularly Affect Women.

    Science.gov (United States)

    Popkin, Mary; Ross, Diane

    This is a guide to legal and collective bargaining solutions for workplace problems that particularly affect women. The first section of the guide presents a survey of legal remedies for discrimination including information on: (1) Title VII; (2) Equal Pay Act; (3) Executive Order 11246; (4) Age Discrimination in Employment Act; and (5) State Fair…

  5. A Test Set for stiff Initial Value Problem Solvers in the open source software R: Package deTestSet

    NARCIS (Netherlands)

    Mazzia, F.; Cash, J.R.; Soetaert, K.

    2012-01-01

    In this paper we present the R package deTestSet that includes challenging test problems written as ordinary differential equations (ODEs), differential algebraic equations (DAEs) of index up to 3 and implicit differential equations (IDES). In addition it includes 6 new codes to solve initial value

  6. Mental Subtraction in High- and Lower Skilled Arithmetic Problem Solvers: Verbal Report versus Operand-Recognition Paradigms

    Science.gov (United States)

    Thevenot, Catherine; Castel, Caroline; Fanget, Muriel; Fayol, Michel

    2010-01-01

    The authors used the operand-recognition paradigm (C. Thevenot, M. Fanget, & M. Fayol, 2007) in order to study the strategies used by adults to solve subtraction problems. This paradigm capitalizes on the fact that algorithmic procedures degrade the memory traces of the operands. Therefore, greater difficulty in recognizing them is expected…

  7. Treatment, alcoholics anonymous, and 16-year changes in impulsivity and legal problems among men and women with alcohol use disorders.

    Science.gov (United States)

    Blonigen, Daniel M; Timko, Christine; Moos, Bernice S; Moos, Rudolf H

    2009-09-01

    The link between impulsive personality traits and alcohol use disorders (AUDs) is well established. No studies, however, have investigated whether receipt of help for AUDs predicts change in impulsivity or whether such change is associated with relevant outcomes such as legal problems. The present study examined predictive associations between the duration of help for AUDs (Alcoholics Anonymous [AA], professional treatment) and impulsivity and legal problems over 16 years in men and women with AUDs. Participants who were initially untreated for their AUDs (n(men) = 332, n(women) = 296) completed follow-up telephone interviews at 1 and 16 years after their baseline assessment. Impulsivity and legal problems declined between baseline and the 1-year and 16-year follow-ups among both women and men. A longer duration of participation in AA predicted a decline in impulsivity at both follow-up assessments, and, in turn, a decline in impulsivity predicted a decline in legal problems at Years 1 and 16. In addition, a longer duration of participation in AA predicted fewer legal problems at Year 1, and this association was moderated by gender (significant in men) and impulsivity (significant for individuals with higher baseline scores). The results highlight the potential for AA and professional treatment to reduce the expression of impulsivity and related disinhibitory traits and legal problems in individuals with AUDs.

  8. Open problems in CEM: Porting an explicit time-domain volume-integral- equation solver on GPUs with OpenACC

    KAUST Repository

    Ergü l, Ö zgü r; Feki, Saber; Al-Jarro, Ahmed; Clo, Alain M.; Bagci, Hakan

    2014-01-01

    -level approach, utilizing the OpenACC directive-based parallel programming model, is used to minimize two often-faced challenges in GPU programming: developer productivity and code portability. The MOT-TDVIE solver code, originally developed for CPUs

  9. Problems of linguistic discrimination in the communicative space of Tajikistan: legal, sociolinguistic and educational aspects

    Directory of Open Access Journals (Sweden)

    Diloro Iskandarova

    2017-11-01

    Full Text Available Although it is disregarded and banned, a person can be discriminated in the society according to various attributes – due to the person's language, religion, nationality, social background. The problem touches upon not only individuals but minorities as well. Almost all states have one or several groups – minorities – that differ from the main population in ethnic, linguistic or religious lines. Most international treaties on human rights contain anti-discriminatory provisions. In addition to the main rights of the freedom of conscience, thought and associations, the principal legal guarantees for each representative of minorities consist in being treated equally by the law and courts and in equal protection of laws. The paper studies the problems of legal, sociolinguistic and educational basis of linguistic discrimination in the communicative space of Tajikistan. Linguistic discrimination and political correctness are closely connected with the language policy of the state. With exoglossic linguistic situation being characteristic for Tajikistan arises a need to study the questions related to linguistic discrimination. This will allow making certain adjustments to language building and harmonizing the ethnic and interethnic interests on the basis of a balanced and scientifically justified language policy.

  10. Biomedical waste management - problems and perspectives: legal, administrative and fiscal viewpoint

    International Nuclear Information System (INIS)

    Jayaraman, S.; Philip, P.C.; Stephens, R.

    1983-01-01

    In recent years, the costs for the disposal of low level radioactive wastes have escalated and the states in which commercial waste disposal sites are located have also been insisting on ''hold harmless'' and indemnity agreements from the users of such sites. Coupled with the above, the uncertainty associated with the sites being kept open, has created a significant problem for the generators of low level wastes, forcing them to look for alternatives such as incineration. This paper attempts to provide an insight into the problem of low level radioactive wastes disposal from the legal, administrative and fiscal viewpoint as it pertains to statesupported teaching medical institution. Some aspects of public relations are also covered

  11. Formation of ecological and legal science: resource aspect and its integration problems

    Directory of Open Access Journals (Sweden)

    А. П. Гетьман

    2016-04-01

    Full Text Available Problem setting. Social and environmental issues of waste management facing society relatively recently, but showed a tendency to expand and deepen, which in turn caused the necessity of formation of effective policy in this area. Recent research and publications analysis. Some aspects of the present stage of the formation of environmental law and its relationship to nature and resources law, structural and systemic connections was studied by various researchers in the context of environmental policy and legislation analysis, regulation of wildlife relationships, expanding the scope of regulation of resource. In particular, they can mark out V. Andreytsev, A. Getman, M. Krasnova, N. Malisheva and others. However, comprehensive studies of this policy is currently not available. Paper objective. The purpose of the article is a theoretical analysis of the current state of environmental law, the formation of the next stage of development of natural resource relationships, their expansion and transformation into a resource (ecologic and resource in order to adequately respond to the differentiation and complexity of structural and systemic linkages. Paper main body. The development and dynamics of the environmental, natural resources legislation is largely driven by global and European processes and requires constant updating in order to overcome gaps, timely and adequate response to contemporary challenges, changes in value paradigms and so forth. One of these problems is the development of traditional branches of law and directions research that, in turn, raises the question of substantive content, structural and systemic links of these areas of law. Any delay in the establishment of the theoretical and methodological and scientific and legal framework for a new legal phenomena in the framework of ecological and legal science creates the preconditions for the expansion of research not only to them but also in relation to the already well

  12. International legal problems of topical interest concerning the peaceful navigation of nuclear ships

    International Nuclear Information System (INIS)

    Bernhardt, R.; Rudolf, W.

    1975-01-01

    The lack of internationally accepted laws on the operation of nuclear ships has proved so far perhaps a more serious obstacle to further development than the problems of a technical-economic kind, although international law by no means that inadequate that it could not, at least basically, do justice to the peaceful navigation of nuclear ships. The unsatisfactory legal situation has been caused in the first place by the conduct of the majority of states which, out of fear of the risks of nuclear ships, also questioned those articles of international maritime law which had been undisputed up to then. This goes in particular for the SOLAS convention, the principles of the peaceful crossing of territorial waters and of calling at ports. On the other hand, it ought to be pointed out, too, that the states obviously do not assume that the operation of nuclear ships is using the sea inadmissably under international law. One could see this as a continuation of the strict Trail-Smelter-doctrine which forbids states to allow activities which might have harmful effects on other national territories. There is no doubt, that the uses of nuclear energy belong to these dangerous activites. At the same time, they are accepted under international law, provided that they are supervised legally and provided that appropriate liability arrangments under civil law are at hand. This is the starting point for over coming the legal difficulties in the peaceful navigation of nuclear ships: it is to be treated as a matter of urgency to elaborate and to put into force comprehensive international conventions for the licensing and supervision of nuclear ships and concerning liablilty under civil law of the operators of nuclear ships. The required freedom in the navigation of nuclaer ships can only be achieved by further reglementation under maritime law. (orig./LN) [de

  13. Problems and Tendencies of Development of Political and Legal Environment of Public-private Partnership in Russia

    Directory of Open Access Journals (Sweden)

    Альберт Илдусович Абдрахманов

    2013-12-01

    Full Text Available The article is dedicated to the study o/f political and legal terms for Public-Private Partnerships (PPP development while PPP becomes the issue of today for Russian political and social-economic life. The article covers particularly the analysis of the effective legislation of PPP at the federal and regional levels and appraisal of the current political trends regarding the development of legal partnership between the government and companies in the connection with the legislation. The author provides research especially of the prospects of the PPP federal Draft Law and reveals key specifics and problems of the legal environment of PPP in districts of the Russian Federation.

  14. Investigating the Difficulties and Problems Faced by the English Language Students of Al Quds Open University in Legal Translation Process

    Directory of Open Access Journals (Sweden)

    Ahmed Maher Mahmoud Al-Nakhalah

    2013-12-01

    Full Text Available Following experimental descriptive method, the paper explores the difficulties and problems faced by the English language students of Al Quds Open University in legal translation process; that is, while translating legal terms/documents from Arabic to English and from English to Arabic. A test was designed by the researcher in order to explore and investigate the difficulties and problems faced by the students. The test included four questions: 1 Translating English legal paragraph, 2 Translating Arabic legal paragraph, 3 Translating ten Arabic legal terms and 4 Translating ten English legal terms. The test was applied on the English language students of Al Quds Open University in Gaza Region in Palestine during the second course of the academic year 2010/2011. The samples of the study were chosen and selected randomly. Following suitable statistical methods, the paper offers the obtained results with critical discussion. Possible solutions, recommendations and suggestions to overcome these difficulties and problems also form important parts of the discussion in the paper.

  15. Parallel Symmetric Eigenvalue Problem Solvers

    Science.gov (United States)

    2015-05-01

    Research” and the use of copyright material. Approved by Major Professor(s): Approved by: Head of the Departmental Graduate Program Date Alicia Marie... matrix . . . . . . . . . . . . . . . . . 106 8.15 Sparsity patterns for the Nastran benchmark of order 1.5 million . . . . 108 8.16 Sparsity patterns...magnitude eigenvalues of a given matrix pencil (A,B) along with their associated eigenvectors. Computing the smallest eigenvalues is more difficult

  16. The Russian oil industry and foreign investments: legal aspects and the problem of business risk

    International Nuclear Information System (INIS)

    Konoplyanik, A.A.

    1994-01-01

    Despite the considerable potential oil resources in Russia, oil production is currently falling to the extent where, if present trends continue, imports will be necessary in the next few years in order to meet domestic demand. Foreign investment could make an effective contribution to stabilizing the Russian oil industry. The large resource base, favourable production costs, highly skilled workers and the conversion potential of the former defence industries to oil and gas equipment, are considerable attractions for foreign investors. However, for the time being there are many obstacles and uncertainties for oil and gas investment. Among these are political instability, high taxation, export tariffs, the legal environment, bureaucratic difficulties over new project negotiation, and problems related to oil and gas transportation. Current legislative activities which may lead to a better investment environment are described. (UK)

  17. Main Tendencies in the Problem of the Legal Collisions Study in Modern Science of the Law Theory

    Directory of Open Access Journals (Sweden)

    Kristina V. Ahmetjanova

    2015-06-01

    Full Text Available In the article the main tendencies within studying of problems of legal collisions in modern jurisprudence are considered. The main attention is paid to a question of consideration of the specified problem from a position of various types of law understanding. By results of the conducted research, author comes to a conclusion that the most part of researches on problems of collisions in law is sustained in the spirit of legal positivism, however there is a number of works in which attempt of consideration of legal collisions from a position of sociological type of understanding of the right is traced. Tendency, according to the author, is the most significant and the specified subject having a certain potential to carrying out further actual researches on.

  18. LEGAL CONSCIOUSNESS OF YOUTH IN CONDITIONS OF VOCATIONAL EDUCATION: PROBLEMS AND SOLUTIONS

    Directory of Open Access Journals (Sweden)

    R. R. Kalinina

    2014-10-01

    Full Text Available Goal: to study peculiarities of legal consciousness among youth in conditions of vocational education in legal and non-legal fields.Methods and practices: empirical (Assessing moral development: dilemmas by L. Kohlberg, Practice of self-analysis diagnostics by A.V. Karpov, Test on legal and civic consciousness by L.A. Yasyukova, “Level of Subjective Control” methodology by E.F. Bazhin et al. and mathematical and statistical methods (descriptive, comparative, and cluster analyses.Result: Peculiarities of contents in legal consciousness and its regulatory function in students of legal and non-legal programs were identified. Three types of students were determined: those with non-formed legal consciousness, with formed legal consciousness and with formal legal consciousness; main directions for psychological and pedagogical work in the university to develop adequate legal consciousness in students of various fields were set.Applicability of results: results of the research can be applied when developing elective courses, extracurricular activities, strategy for character-building work of the university, both in training lawyers and other professionals.

  19. Protection of children's rights in the health care: problems and legal issues.

    Science.gov (United States)

    Pashkov, Vitaliy; Olefir, Andrii

    Introduction: Among all categories of patients children (minors) must be protected first. It is caused so by the specificity of the treatment, their vulnerability, the need of further protection and supervision. Providing of medical care services for children are often connected with the risks of the process of treatment, and of the drug usage. The aim: To identify the problems associated with the protection of the rights of minors and, on the basis of this, the basic guarantees of their rights, as well as mark the trends in the practice of ECHR. Materials and Methods: The study is based on its own theoretical and empirical basis. The theoretical basis include scientific articles, expert reviews of legislation and communications of non-governmental organisations, and empirical - decisions of the ECHR, international legal acts and directives of the EU. Results: The main violations of the rights of minor children include the following: - legal representatives of children do not take to the account their interests (refusal of medical intervention or the choice of certain method of interference); - medical intervention under the influence of coercion; - providing of unwarranted medical care without the corresponding testimony; - providing of inadequate medical care: when the patient was only examined and ineffective treatment was prescribed, and others. As for mentally ill children, the following rights are usually violated: for life, for a fair trial. It has been proved that defects in the provision of health care are often predetermined by the poor state logistics of hospitals, lack of financing and appropriate pediatric medicines, outdated methods of treatment, and incompetence of some doctors. Conclusions: From the point of view of protecting the rights of minors, the rights of children in medicine can be classified into universal and special. The rights correspond not only to the corresponding duties of medical staff, but also of their parents (legal

  20. PROBLEM ASPECTS OF FORMATION OF THE LEGAL INSTITUTE OF CONSOLIDATED TAXPAYERS’ GROUPS IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Irina Glazunova

    2017-01-01

    Full Text Available The subject. The article is devoted to the prerequisites of the emergence and essential characteristics of the institution of consolidated taxpayers’ groups in Russia and abroad, revealing of advantages and disadvantages of the legal regulation of the creation and operation of consolidated groups of payers of corporate profits tax, analyzing results and directions of the development of tax consolidation in Russian Federation.The purpose of the article is to identify positive and negative aspects of the functioning of the institution of consolidated taxpayers’ groups in Russia with the establishment of prospects of tax consolidation and the likely directions of its development.The description of the problem field. The development of the world economic system stimulates the emergence of new forms of management, characterized by the enlargement of busi-ness, the pooling of resources of individual enterprises into a single system in order to optimize entrepreneurial activity. These trends are reflected in the development of tax systems of various countries, that is expressed in the formation of institutions of consolidated taxpayers’ groups. Tax consolidation in Russia is a relatively new phenomenon, and it seems necessary to examine this institution from the law enforcement point of view, to evaluate its effectiveness.Methods and methodology. The authors used methods of analysis, synthesis, as well as formal-legal, comparative-legal, historical methods of investigation.Results and the scope of its application. The authors note that the institution of tax consolidation today is presented in the tax systems of most modern countries.The practice of applying the institution of consolidated taxpayers’ groups testifies to the existence of a significant number of advantages and disadvantages of tax consolidation in Russia. The moratorium on the creation of consolidated taxpayers’ groups, due to the contradictory nature of their influence on the

  1. Comparing direct and iterative equation solvers in a large structural analysis software system

    Science.gov (United States)

    Poole, E. L.

    1991-01-01

    Two direct Choleski equation solvers and two iterative preconditioned conjugate gradient (PCG) equation solvers used in a large structural analysis software system are described. The two direct solvers are implementations of the Choleski method for variable-band matrix storage and sparse matrix storage. The two iterative PCG solvers include the Jacobi conjugate gradient method and an incomplete Choleski conjugate gradient method. The performance of the direct and iterative solvers is compared by solving several representative structural analysis problems. Some key factors affecting the performance of the iterative solvers relative to the direct solvers are identified.

  2. A Novel Interactive MINLP Solver for CAPE Applications

    DEFF Research Database (Denmark)

    Henriksen, Jens Peter; Støy, S.; Russel, Boris Mariboe

    2000-01-01

    This paper presents an interactive MINLP solver that is particularly suitable for solution of process synthesis, design and analysis problems. The interactive MINLP solver is based on the decomposition based MINLP algorithms, where a NLP sub-problem is solved in the innerloop and a MILP master pr...

  3. Legal problems in the concretisation of the fundamental requirements on radiation protection. 1. paper

    International Nuclear Information System (INIS)

    Bartholdy, V.

    1980-01-01

    The author deals with questions of radioecological regulations based on Sect. 45 p. 2 of the Radiation Protection Ordinance, emphasizing its significance for the transparency of decision-making processes under the Atomic Energy Law - which is not only a legally relevant aspect in the interest of debunking the discussion on nuclear energy utilization, but also under constitutional criteria of legal clarity. (HP) [de

  4. Investigation on legal problems encountered by emergency medicine physicians in Turkey.

    Science.gov (United States)

    Kayipmaz, Afsin Emre; Kavalci, Cemil; Gulalp, Betul; Kocalar, Ummu Gulsum; Giray, Tufan Akin; Yesilagac, Hasan; Ozel, Betul Akbuga; Celikel, Elif; Karagun, Ozlem

    2015-01-01

    Medicine is a profession that carries certain risks. One risky area of practice is the emergency department. Emergency physicians diagnose and treat a high volume of patients, and are also responsible for preparing reports for forensic cases. In this study, we aim to investigate emergency physicians' legal-administrative problems and reveal their level of understanding on forensic cases. An electronic questionnaire form was prepared after the approval of an ethical committee. This form was sent to the residents, specialists and academicians of emergency medicine by e-mail. The physicians were asked to fill out the form online. All the gathered data was analyzed. Descriptive statistics were presented as frequency percentages with mean and standard deviation. Chi-square tests were used to compare the groups. Correlation between number of complaint cases and age, sex, career, institution, and duration of service in emergency department were investigated. pmedicine and age. There was a significant difference between number of complaint reports and career (p<0.05). The physicians' level of awareness on forensic cases was found to be insufficient. Lack of legislation knowledge may be an important cause of complaint reports concerning emergency physicians, who have a high load of patients. Thus, we think that increasing the frequency of post-graduate education sessions and periodical reviews might be beneficial.

  5. LEGAL PROTECTION OF AVIATION IN THE CONTEXT OF GLOBALIZATION, RISKS AND SOCIAL ENTROPY AS A SCIENTIFIC PROBLEM: APPROACHES AND SOLUTIONS

    Directory of Open Access Journals (Sweden)

    O. O. Chernaya

    2015-01-01

    Full Text Available The article considers the issue concerning the international legal problem of using armed forces to counter the threats posed by the misuse of civil aircraft, in particular, the use of civil aircraft as a weapon to kill people and destroy objects on the territory of States (the events of 11th September 2001 in the USA. It proves the need for universal international legal norms regulating the actions of States to prevent and suppress acts of the misuse of civil aircraft.

  6. Open problems in CEM: Porting an explicit time-domain volume-integral- equation solver on GPUs with OpenACC

    KAUST Repository

    Ergül, Özgür

    2014-04-01

    Graphics processing units (GPUs) are gradually becoming mainstream in high-performance computing, as their capabilities for enhancing performance of a large spectrum of scientific applications to many fold when compared to multi-core CPUs have been clearly identified and proven. In this paper, implementation and performance-tuning details for porting an explicit marching-on-in-time (MOT)-based time-domain volume-integral-equation (TDVIE) solver onto GPUs are described in detail. To this end, a high-level approach, utilizing the OpenACC directive-based parallel programming model, is used to minimize two often-faced challenges in GPU programming: developer productivity and code portability. The MOT-TDVIE solver code, originally developed for CPUs, is annotated with compiler directives to port it to GPUs in a fashion similar to how OpenMP targets multi-core CPUs. In contrast to CUDA and OpenCL, where significant modifications to CPU-based codes are required, this high-level approach therefore requires minimal changes to the codes. In this work, we make use of two available OpenACC compilers, CAPS and PGI. Our experience reveals that different annotations of the code are required for each of the compilers, due to different interpretations of the fairly new standard by the compiler developers. Both versions of the OpenACC accelerated code achieved significant performance improvements, with up to 30× speedup against the sequential CPU code using recent hardware technology. Moreover, we demonstrated that the GPU-accelerated fully explicit MOT-TDVIE solver leveraged energy-consumption gains of the order of 3× against its CPU counterpart. © 2014 IEEE.

  7. Investigation on legal problems encountered by emergency medicine physicians in Turkey.

    Directory of Open Access Journals (Sweden)

    Afsin Emre Kayipmaz

    Full Text Available Medicine is a profession that carries certain risks. One risky area of practice is the emergency department. Emergency physicians diagnose and treat a high volume of patients, and are also responsible for preparing reports for forensic cases. In this study, we aim to investigate emergency physicians' legal-administrative problems and reveal their level of understanding on forensic cases.An electronic questionnaire form was prepared after the approval of an ethical committee. This form was sent to the residents, specialists and academicians of emergency medicine by e-mail. The physicians were asked to fill out the form online. All the gathered data was analyzed. Descriptive statistics were presented as frequency percentages with mean and standard deviation. Chi-square tests were used to compare the groups. Correlation between number of complaint cases and age, sex, career, institution, and duration of service in emergency department were investigated. p<0.05 was considered statistically significant.294 physicians participated in the questionnaire. According to the questionnaire, 170 of the physicians were reported to the patient communication units due to medical malpractice. Mean number of compliant reports was 3.20±3.5. 29 of the physicians received administrative penalties. 42 of the physicians were judged in the court for medical malpractice. 1 physician was fined 5000 Turkish Liras as a result of these judgments.We found that the number of complaint reports is negatively correlated with duration of service in emergency medicine and age. There was a significant difference between number of complaint reports and career (p<0.05. The physicians' level of awareness on forensic cases was found to be insufficient. Lack of legislation knowledge may be an important cause of complaint reports concerning emergency physicians, who have a high load of patients. Thus, we think that increasing the frequency of post-graduate education sessions and

  8. e-Learning strategies in occupational legal medicine based on problem solving through "CASUS" system.

    Science.gov (United States)

    Martínez-Jarreta, B; Monsó, E; Gascón, S; Casalod, Y; Abecia, E; Kolb, S; Reichert, J; Radon, K

    2009-04-01

    The use of online teaching tools facilitate the incorporation of self-learning methods. With a view to encouraging convergence in teaching tools and methods in Occupational Legal Medicine, an initiative was set up within the classes of Legal and Forensic Medicine at Saragossa University, as part of the EU funded NetWoRM project, which has been led since 1999 by Ludwig-Maximilians-Universität in Munich (Germany). The interest of medical students in Occupational Legal Medicine has so far been low and in addition different aspects complicate the teaching of Occupational Legal Medicine at medical schools: One reason for the low interest is the limited availability of bedside teaching, one of the students' most favourite and effective way to learn. The reason for that is that most medical schools with occupational departments only have outpatient clinics. "Interesting" patients who be need for educational purposes are therefore only available for a limited part of the day. However, in order to recognize and prevent occupational disorders each medical student and physician needs profound clinical knowledge in Occupational Legal Medicine. This project has proven to be highly efficient in permitting the creation and validation of teaching tools which cover and improve the traditional training of the Occupational Legal Medicine programme imparted in the degree of Medicine.

  9. Legal problems raised in Italy by the ratification of the Convention in Physical Protection - implications in Europe

    International Nuclear Information System (INIS)

    Albano, R.; Crocenzi, G.

    1983-01-01

    This paper examines the legal problems which arose in Italy when the Convention on the Physical Protection of Nuclear Material, opened for signature in 1980, was ratified by that country in 1982. The purpose and background of the Convention and its relationship with other international regulations, in particular in the field of transport, are analysed in detail. Finally, the paper reviews the main European laws (French, German and British) on physical protection of nuclear material. (NEA) [fr

  10. Problems of applying legal liability for offenses in the sphere of long-term temporary usage of forests in Ukraine

    Directory of Open Access Journals (Sweden)

    Д. М. Мікулин

    2015-11-01

    Full Text Available Problem setting. Today the institute of legal responsibility functionates inefficiently, which can be explained by a weak theoretical development problems of this institution in particular legal sciences (including the environmental law; legislative gaps; low level of skills of the executive officers in the field of environmental protection, rational use, restoration and protection of natural resources. These provisions completely relate as well to the problems of applying legal responsibility for violations in the field of long-term temporary use of forests. Recent research and publications analysis. Issues of legal responsibility for offenses in the sphere of forest usage were considered in the scientific works of B. Boreiko, S. Kravchenko, O. Shumilo, O. Storchous etc. Anyhow, the legal precedents in the scope of offenses in the sphere of long-term temporary usage of forests in Ukraine remains not studied. Paper objective is the analysis of the most typical recent legal cases in the scope of long-term temporary usage of forests that demonstrate the roots for conflicts between the forest users, local public authorities and the public. Paper main body. Based the an analysis of cited precedents, it can be unequivocally concluded that the forest legislation doesn’t regulate efficiently the liability for violations in the field of long-term temporary usage of forests in Ukraine. Forest users often fail to comply with the contract terms of using forests in the part of veto on business activity, as well as constructing fences, that impedes the access of local residents to natural resources. The procedure for receiving forest lands in temporary usage is extremely corrupt, and citizens have to go to court to bring regional administrations to administrative responsibility for unjustified refusal to provide forest lands in the long-term temporary usage. Conclusions of the research. Author believes that the effective solution of modern problems is not

  11. To the problem of improving normative legal basis of organization of local self-government in Russia

    Directory of Open Access Journals (Sweden)

    Olga Bazhenova

    2017-01-01

    Full Text Available The subject. The crisis of local self-government actualizes the problem of effectiveness oflegal regulation of the issues of its organization.The purpose of the paper is evaluation of the effectiveness of the regulatory framework forthe organization of local government.The methodology of research includes systematic analysis, formal legal method, interpretationof legislation.The results and scope of application. The crisis of local self-government actualizes the problemof effectiveness of legal regulation of the issues of its organization. Evaluation of theeffectiveness of the regulatory framework for the organization of local government is reducedto two questions: what are the limits of state legal regulation and what are the beginningof the division of powers on the organization of local government between the RussianFederation and the subjects of the Russian Federation.Recognizing the optimal legislative approach to the definition of the limits of state regulation,which assumes the creation at the federal level of a full-fledged legal mechanism for the implementationof local self-government, subject to its combination with the beginning of municipalself-regulation, the author criticizes the legislative approach to delineating the powersto organize local self-government between the Federation and the subjects of the Federation.Conclusions. Due to the legislative formula, according to which the scope of regional powersdepends on the discretion of the federal legislator, the local self-government turned out tobe "hostage" to the emerging federal relations.

  12. Benchmarking optimization solvers for structural topology optimization

    DEFF Research Database (Denmark)

    Rojas Labanda, Susana; Stolpe, Mathias

    2015-01-01

    solvers in IPOPT and FMINCON, and the sequential quadratic programming method in SNOPT, are benchmarked on the library using performance profiles. Whenever possible the methods are applied to both the nested and the Simultaneous Analysis and Design (SAND) formulations of the problem. The performance...

  13. On a construction of fast direct solvers

    Czech Academy of Sciences Publication Activity Database

    Práger, Milan

    2003-01-01

    Roč. 48, č. 3 (2003), s. 225-236 ISSN 0862-7940 Institutional research plan: CEZ:AV0Z1019905; CEZ:AV0Z1019905 Keywords : Poisson equation * boundary value problem * fast direct solver Subject RIV: BA - General Mathematics

  14. vZ - An Optimizing SMT Solver

    DEFF Research Database (Denmark)

    Bjørner, Nikolaj; Dung, Phan Anh; Fleckenstein, Lars

    2015-01-01

    vZ is a part of the SMT solver Z3. It allows users to pose and solve optimization problems modulo theories. Many SMT applications use models to provide satisfying assignments, and a growing number of these build on top of Z3 to get optimal assignments with respect to objective functions. vZ provi...

  15. Two-dimensional time dependent Riemann solvers for neutron transport

    International Nuclear Information System (INIS)

    Brunner, Thomas A.; Holloway, James Paul

    2005-01-01

    A two-dimensional Riemann solver is developed for the spherical harmonics approximation to the time dependent neutron transport equation. The eigenstructure of the resulting equations is explored, giving insight into both the spherical harmonics approximation and the Riemann solver. The classic Roe-type Riemann solver used here was developed for one-dimensional problems, but can be used in multidimensional problems by treating each face of a two-dimensional computation cell in a locally one-dimensional way. Several test problems are used to explore the capabilities of both the Riemann solver and the spherical harmonics approximation. The numerical solution for a simple line source problem is compared to the analytic solution to both the P 1 equation and the full transport solution. A lattice problem is used to test the method on a more challenging problem

  16. Social Reform Groups and the Legal System: Enforcement Problems. Discussion Paper No. 209-74.

    Science.gov (United States)

    Handler, Joel F.

    During the last two decades, there has been a great increase in the use of litigation by social reform groups. This activity has been stimulated by the hospitality of the courts to the demands of social reform groups and the availability of subsidized young, activist lawyers. The paper examines the uses of the legal system by social reform groups…

  17. Stalking. Part II: Victims' problems with the legal system and therapeutic considerations.

    Science.gov (United States)

    Abrams, K M; Robinson, G E

    1998-06-01

    This paper is the second of 2 parts reviewing the topic of stalking. It focuses on victims difficulties with the legal system and the psychotherapeutic tasks for victims and therapists. Computerized literature searches were used to identify relevant papers from psychiatric and legal journals. Publications by victims' and women's organizations provided additional information. Victims suffer emotional consequences from being stalked. Additional stress is caused by the legal system's lack of understanding of the causes and consequences of stalking and inadequate and unenforced laws. The treatment of victims requires a comprehensive approach, including education, supportive psychotherapy, and discussion of practical measures. Therapists may overidentify with the patient's powerlessness or hesitate to take on a case out of fear of the stalker. Female therapists may protect themselves against the realization of their own vulnerability by blaming the victim, while male therapists may feel defensive or overprotective. Stalking is a crime with major mental health consequences which is often poorly understood by society. Therapists need to be aware of the victim's emotional reactions, the types of legal and practical supports available, and the possible biases of society. Further education and research should be encouraged.

  18. Scientific-practical and legal problems of implementation of the personalized medicine.

    Science.gov (United States)

    Bezdieniezhnykh, N O; Reznikova, V V; Rossylna, O V

    2017-09-01

    The article is devoted to the comprehensive analysis of scientific, practical and legal issues of personalized medicine that is a rapidly developing science-driven approach to healthcare. It is concluded that there is lack of general legal framework for the encouragement of scientific researches and practical implementation in this field. The article shows foreign experience and prospects for the introduction of personalized medicine as a key concept of healthcare system, which is based on a selection of diagnostic, therapeutic and preventive measures that would be the most effective for a particular person in view of individual characteristics. The conclusions and proposals to improve the current legislation and development of personalized medicine in Ukraine are suggested.

  19. Parallel sparse direct solver for integrated circuit simulation

    CERN Document Server

    Chen, Xiaoming; Yang, Huazhong

    2017-01-01

    This book describes algorithmic methods and parallelization techniques to design a parallel sparse direct solver which is specifically targeted at integrated circuit simulation problems. The authors describe a complete flow and detailed parallel algorithms of the sparse direct solver. They also show how to improve the performance by simple but effective numerical techniques. The sparse direct solver techniques described can be applied to any SPICE-like integrated circuit simulator and have been proven to be high-performance in actual circuit simulation. Readers will benefit from the state-of-the-art parallel integrated circuit simulation techniques described in this book, especially the latest parallel sparse matrix solution techniques. · Introduces complicated algorithms of sparse linear solvers, using concise principles and simple examples, without complex theory or lengthy derivations; · Describes a parallel sparse direct solver that can be adopted to accelerate any SPICE-like integrated circuit simulato...

  20. The legal, moral and ethical aspects and problems of perception of information

    Directory of Open Access Journals (Sweden)

    Алла Борисовна Денисова

    2012-12-01

    Full Text Available At the present time, when the profits from crimes by means of computer technologies, according to Interpol, in third place after the income of drugs traffickers and illegal arms suppliers, the company is aware that professionals in the field of information technology alone are not enough professional knowledge and skills. In order to prevent deviant behavior in cyberspace, and the correct address ethical issues that arise in their professional activities, legal and ethical regulation of social relations in the sphere of information technologies.

  1. ALPS: A Linear Program Solver

    Science.gov (United States)

    Ferencz, Donald C.; Viterna, Larry A.

    1991-01-01

    ALPS is a computer program which can be used to solve general linear program (optimization) problems. ALPS was designed for those who have minimal linear programming (LP) knowledge and features a menu-driven scheme to guide the user through the process of creating and solving LP formulations. Once created, the problems can be edited and stored in standard DOS ASCII files to provide portability to various word processors or even other linear programming packages. Unlike many math-oriented LP solvers, ALPS contains an LP parser that reads through the LP formulation and reports several types of errors to the user. ALPS provides a large amount of solution data which is often useful in problem solving. In addition to pure linear programs, ALPS can solve for integer, mixed integer, and binary type problems. Pure linear programs are solved with the revised simplex method. Integer or mixed integer programs are solved initially with the revised simplex, and the completed using the branch-and-bound technique. Binary programs are solved with the method of implicit enumeration. This manual describes how to use ALPS to create, edit, and solve linear programming problems. Instructions for installing ALPS on a PC compatible computer are included in the appendices along with a general introduction to linear programming. A programmers guide is also included for assistance in modifying and maintaining the program.

  2. Crossing the line: the legal and ethical problems of foreign surrogacy.

    Science.gov (United States)

    Gamble, Natalie

    2009-08-01

    UK law has for many years taken a careful approach to surrogacy, neither banning it nor allowing it to develop unrestrictedly. This careful middle approach seeks to balance permitting what may be a last hope for infertile couples against a wider public policy that bars commercialized reproduction: surrogacy is allowed in the UK, provided it is consensual and involves the payment of no more than reasonable expenses. But in an increasingly globalized world, patients are crossing borders for treatment, often to places where such restrictions on the commerciality or enforceability of surrogacy arrangements do not apply. The resulting conflicts of law can be a minefield, and this makes the maintenance of the UK's careful legal balance increasingly untenable.

  3. Comparison of open-source linear programming solvers.

    Energy Technology Data Exchange (ETDEWEB)

    Gearhart, Jared Lee; Adair, Kristin Lynn; Durfee, Justin David.; Jones, Katherine A.; Martin, Nathaniel; Detry, Richard Joseph

    2013-10-01

    When developing linear programming models, issues such as budget limitations, customer requirements, or licensing may preclude the use of commercial linear programming solvers. In such cases, one option is to use an open-source linear programming solver. A survey of linear programming tools was conducted to identify potential open-source solvers. From this survey, four open-source solvers were tested using a collection of linear programming test problems and the results were compared to IBM ILOG CPLEX Optimizer (CPLEX) [1], an industry standard. The solvers considered were: COIN-OR Linear Programming (CLP) [2], [3], GNU Linear Programming Kit (GLPK) [4], lp_solve [5] and Modular In-core Nonlinear Optimization System (MINOS) [6]. As no open-source solver outperforms CPLEX, this study demonstrates the power of commercial linear programming software. CLP was found to be the top performing open-source solver considered in terms of capability and speed. GLPK also performed well but cannot match the speed of CLP or CPLEX. lp_solve and MINOS were considerably slower and encountered issues when solving several test problems.

  4. The consistency effect depends on markedness in less succesful but not succesful problem solvers: An eye movement study in primary school children

    NARCIS (Netherlands)

    van der Schoot, M.; Bakker Arkema, A.H.; Horsley, T.M.; van Lieshout, E.C.D.M.

    2009-01-01

    This study examined the effects of consistency (relational term consistent vs. inconsistent with required arithmetic operation) and markedness (relational term unmarked ['more than'] vs. marked ['less than']) on word problem solving in 10-12 years old children differing in problem-solving skill. The

  5. Mathematical programming solver based on local search

    CERN Document Server

    Gardi, Frédéric; Darlay, Julien; Estellon, Bertrand; Megel, Romain

    2014-01-01

    This book covers local search for combinatorial optimization and its extension to mixed-variable optimization. Although not yet understood from the theoretical point of view, local search is the paradigm of choice for tackling large-scale real-life optimization problems. Today's end-users demand interactivity with decision support systems. For optimization software, this means obtaining good-quality solutions quickly. Fast iterative improvement methods, like local search, are suited to satisfying such needs. Here the authors show local search in a new light, in particular presenting a new kind of mathematical programming solver, namely LocalSolver, based on neighborhood search. First, an iconoclast methodology is presented to design and engineer local search algorithms. The authors' concern about industrializing local search approaches is of particular interest for practitioners. This methodology is applied to solve two industrial problems with high economic stakes. Software based on local search induces ex...

  6. Use of Tabu Search in a Solver to Map Complex Networks onto Emulab Testbeds

    National Research Council Canada - National Science Library

    MacDonald, Jason E

    2007-01-01

    The University of Utah's solver for the testbed mapping problem uses a simulated annealing metaheuristic algorithm to map a researcher's experimental network topology onto available testbed resources...

  7. Legal problems in the concretisation of the fundamental requirements on radiation protection. 2. paper

    International Nuclear Information System (INIS)

    Schattke, H.

    1980-01-01

    In contrast to justice administered by the Higher Administrative Court of Lueneburg, the author is of the opinion that the individual third party complaing within the framework of the rule to minimize radiation exposure laid down in the Radiation Protection Ordinance cannot refer to risks the population might be exposed to. This is the imperative consequence of the legal system which protects the individual. The fact that - contrary to the position held by the Higher Administrative Court of Lueneburg - Sections 45 and 46 of the Radiation Protection Ordinance include emissions caused by accidents is demonstrated by giving a word-for-word, systematical and teleological interpretation, using painstaking methods. The same goes for the importance of accident doses planned in Sect. 28 of the Radiation Protection Ordinance. To the extent to which it examines the import the basis of authorization would have for a radioecological ordinance, this contribution helps to understand the principles that govern radiation protection and the importance they have for licensing procedures under the Atomic Energy Law in general. (HP) [de

  8. Evolving effective incremental SAT solvers with GP

    OpenAIRE

    Bader, Mohamed; Poli, R.

    2008-01-01

    Hyper-Heuristics could simply be defined as heuristics to choose other heuristics, and it is a way of combining existing heuristics to generate new ones. In a Hyper-Heuristic framework, the framework is used for evolving effective incremental (Inc*) solvers for SAT. We test the evolved heuristics (IncHH) against other known local search heuristics on a variety of benchmark SAT problems.

  9. A 3D finite-difference BiCG iterative solver with the Fourier-Jacobi preconditioner for the anisotropic EIT/EEG forward problem.

    Science.gov (United States)

    Turovets, Sergei; Volkov, Vasily; Zherdetsky, Aleksej; Prakonina, Alena; Malony, Allen D

    2014-01-01

    The Electrical Impedance Tomography (EIT) and electroencephalography (EEG) forward problems in anisotropic inhomogeneous media like the human head belongs to the class of the three-dimensional boundary value problems for elliptic equations with mixed derivatives. We introduce and explore the performance of several new promising numerical techniques, which seem to be more suitable for solving these problems. The proposed numerical schemes combine the fictitious domain approach together with the finite-difference method and the optimally preconditioned Conjugate Gradient- (CG-) type iterative method for treatment of the discrete model. The numerical scheme includes the standard operations of summation and multiplication of sparse matrices and vector, as well as FFT, making it easy to implement and eligible for the effective parallel implementation. Some typical use cases for the EIT/EEG problems are considered demonstrating high efficiency of the proposed numerical technique.

  10. The Legal Problems about Surrogacy Contract%代孕合同之法律问题探讨

    Institute of Scientific and Technical Information of China (English)

    余艳清

    2012-01-01

    我国法律时代孕采取禁止态度。从而使日渐增多的代孕现象呈现无法可依的状态。妊娠代孕具有合法的权利基础。符合公序良俗。能稳定婚姻家庭,应承认其合法性。要从根本上解决代孕所带来的一系列法律问题,在我国未来立法中代孕合同不应只限定在无偿代孕中。还应该明确承认部分商业代孕合同的法律地位。在未来立法中,我国应对代孕合同的主体资格、基本原则、记我事项、代孕母的堕胎权、违约责任等进行全面、系统的规定。%The law is to prohibit surrogacy in our country. Thereby the increasing surrogate phenomenon appears no laws to abide by. The pregnancy surrogacy has the basis of legal right, which is consistent with the public order and the good custom, and is also beneficial to the stability of marriage household; therefore, it should be acknowledged in its legal status. To radically solve a series of legal problems that the surrogate has brought about, in the future legislation, the contracts about surrogacy should not be limited within that of no payment, but also clearly acknowledge the legal status about part of commercial surrogacy contract. In the future legislation, the surrogacy contract about main qualification, basic principle, record items, the pregnant women's rights of abortion, and responsibility of breaking a contract and so on should be stipulated comprehensively and systematically.

  11. NESTLE: Few-group neutron diffusion equation solver utilizing the nodal expansion method for eigenvalue, adjoint, fixed-source steady-state and transient problems

    International Nuclear Information System (INIS)

    Turinsky, P.J.; Al-Chalabi, R.M.K.; Engrand, P.; Sarsour, H.N.; Faure, F.X.; Guo, W.

    1994-06-01

    NESTLE is a FORTRAN77 code that solves the few-group neutron diffusion equation utilizing the Nodal Expansion Method (NEM). NESTLE can solve the eigenvalue (criticality); eigenvalue adjoint; external fixed-source steady-state; or external fixed-source. or eigenvalue initiated transient problems. The code name NESTLE originates from the multi-problem solution capability, abbreviating Nodal Eigenvalue, Steady-state, Transient, Le core Evaluator. The eigenvalue problem allows criticality searches to be completed, and the external fixed-source steady-state problem can search to achieve a specified power level. Transient problems model delayed neutrons via precursor groups. Several core properties can be input as time dependent. Two or four energy groups can be utilized, with all energy groups being thermal groups (i.e. upscatter exits) if desired. Core geometries modelled include Cartesian and Hexagonal. Three, two and one dimensional models can be utilized with various symmetries. The non-linear iterative strategy associated with the NEM method is employed. An advantage of the non-linear iterative strategy is that NSTLE can be utilized to solve either the nodal or Finite Difference Method representation of the few-group neutron diffusion equation

  12. Historians and the Problem of Rights: From the Perspective of Comparative Studies of Legal History

    Institute of Scientific and Technical Information of China (English)

    ChenYing,; ZhaoBaohua; DavidKelly

    2004-01-01

    Selecting the right angle to approach a question is critical for any branch of learning, and it is no accident that today's Chinese historians take the problem of rights as a starting point for their research. When the method chosen answers the question, the research is capable of satisfying practical social development needs.

  13. Problems of Linguistic Discrimination in the Communicative Space of Tajikistan: Legal, Sociolinguistic and Educational Aspects

    Science.gov (United States)

    Iskandarova, Diloro; Ladygina, Olga; Shambezoda, Khusrav; Zolotukhin, Alexey; Abdukhamitov, Valijon

    2017-01-01

    Although it is disregarded and banned, a person can be discriminated in the society according to various attributes--due to the person's language, religion, nationality, social background. The problem touches upon not only individuals but minorities as well. Almost all states have one or several groups--minorities--that differ from the main…

  14. Legal and administrative problems in regulating public participation in licensing of nuclear installations

    International Nuclear Information System (INIS)

    Cornelis, J.C.

    1981-10-01

    This general analysis of the question of public acceptance of nuclear activities focuses on the problems met by all governmental authorities in implementing their nuclear programmes. The author highlights the need for more specific regulations aimed at guaranteeing fuller information of the public and ensuring closer participation by it. (NEA) [fr

  15. Solution of problems with material nonlinearities with a coupled finite element/boundary element scheme using an iterative solver. Yucca Mountain Site Characterization Project

    International Nuclear Information System (INIS)

    Koteras, J.R.

    1996-01-01

    The prediction of stresses and displacements around tunnels buried deep within the earth is an important class of geomechanics problems. The material behavior immediately surrounding the tunnel is typically nonlinear. The surrounding mass, even if it is nonlinear, can usually be characterized by a simple linear elastic model. The finite element method is best suited for modeling nonlinear materials of limited volume, while the boundary element method is well suited for modeling large volumes of linear elastic material. A computational scheme that couples the finite element and boundary element methods would seem particularly useful for geomechanics problems. A variety of coupling schemes have been proposed, but they rely on direct solution methods. Direct solution techniques have large storage requirements that become cumbersome for large-scale three-dimensional problems. An alternative to direct solution methods is iterative solution techniques. A scheme has been developed for coupling the finite element and boundary element methods that uses an iterative solution method. This report shows that this coupling scheme is valid for problems where nonlinear material behavior occurs in the finite element region

  16. RESEARCH ON THE LEGAL PROBLEMS OF THE PORT MANAGEMENT SYSTEM IN JAPAN

    OpenAIRE

    TAKAHASHI, Koji; KASUGAI, Yasuo; FUKUDA, Isao

    2014-01-01

    Across the world, port management is increasingly adopting a scheme of separatinginfrastructure and operations. In the midst of this global trend, Japan experienced the Great Hanshin andAwaji Earthquake in 1995 and the Great East Japan Earthquake in 2011, both of which devastated majorports, forcing Japan to face challenges related to its port management system. In addition, with majorearthquakes expected to strike again in the future, it is urgent for Japan to solve the current problems. Jap...

  17. Parallel iterative solvers and preconditioners using approximate hierarchical methods

    Energy Technology Data Exchange (ETDEWEB)

    Grama, A.; Kumar, V.; Sameh, A. [Univ. of Minnesota, Minneapolis, MN (United States)

    1996-12-31

    In this paper, we report results of the performance, convergence, and accuracy of a parallel GMRES solver for Boundary Element Methods. The solver uses a hierarchical approximate matrix-vector product based on a hybrid Barnes-Hut / Fast Multipole Method. We study the impact of various accuracy parameters on the convergence and show that with minimal loss in accuracy, our solver yields significant speedups. We demonstrate the excellent parallel efficiency and scalability of our solver. The combined speedups from approximation and parallelism represent an improvement of several orders in solution time. We also develop fast and paralellizable preconditioners for this problem. We report on the performance of an inner-outer scheme and a preconditioner based on truncated Green`s function. Experimental results on a 256 processor Cray T3D are presented.

  18. Modelling of natural convection flows with large temperature differences: a benchmark problem for low Mach number solvers. Part. 1 reference solutions

    International Nuclear Information System (INIS)

    Le Quere, P.; Weisman, C.; Paillere, H.; Vierendeels, J.; Dick, E.; Becker, R.; Braack, M.; Locke, J.

    2005-01-01

    Heat transfer by natural convection and conduction in enclosures occurs in numerous practical situations including the cooling of nuclear reactors. For large temperature difference, the flow becomes compressible with a strong coupling between the continuity, the momentum and the energy equations through the equation of state, and its properties (viscosity, heat conductivity) also vary with the temperature, making the Boussinesq flow approximation inappropriate and inaccurate. There are very few reference solutions in the literature on non-Boussinesq natural convection flows. We propose here a test case problem which extends the well-known De Vahl Davis differentially heated square cavity problem to the case of large temperature differences for which the Boussinesq approximation is no longer valid. The paper is split in two parts: in this first part, we propose as yet unpublished reference solutions for cases characterized by a non-dimensional temperature difference of 0.6, Ra 10 6 (constant property and variable property cases) and Ra = 10 7 (variable property case). These reference solutions were produced after a first international workshop organized by Cea and LIMSI in January 2000, in which the above authors volunteered to produce accurate numerical solutions from which the present reference solutions could be established. (authors)

  19. Osteoporosis: A Future Public Health Problem for Israel? Medical and Legal Obligations.

    Science.gov (United States)

    Weisz, George M

    2017-04-01

    Starvation in early life can lead to premature metabolic syndrome and bone demineralization. Osteoporosis in the Jewish population may not yet be a recognized syndrome, but the harsh conditions to which Holocaust survivors were exposed may have increased the incidence of the condition. Immigrants and refugees who came to Israel from East Africa and Yemen - whether decades ago or more recently - may have been at increased risk of under-nutrition during pregnancy, affecting both the mother and consequently the offspring. This malnutrition may be further exacerbated by rapid overfeeding in the adopted developed country. This problem was also recognized at the turn of the 21st century in poor and underdeveloped countries and is becoming a global public health issue. In this review, the risks for premature metabolic syndrome and bone demineralization are enumerated and preventive measures outlined.

  20. Russian law: the legal framework for foreign investment in the Russian petroleum industry - problems and progress

    International Nuclear Information System (INIS)

    Barmin, A.; Doeh, D.

    1994-01-01

    Recent developments in Russian law relating to foreign investment in the petroleum industry are reviewed. The central piece of legislation regulating foreign investment is the Law on Foreign Investments of 1991. Its significance is that it is opened up to foreign investment that had been a closed society but it did not set out how and or what conditions investors' rights were to be acquired and exercised. The main problems that have had to be dealt with include: determining which government authorities (federal, republic, regional etc.) have the power to grant petroleum exploration and production rights; determining the methods by which these rights may be obtained and on what terms; determining export rights; establishing the basis for taxation; establishing the general framework for foreign investment in Russia. The extent to which these issues have been resolved is discussed and remaining areas of concern considered. (UK)

  1. RELATIVISTIC MAGNETOHYDRODYNAMICS: RENORMALIZED EIGENVECTORS AND FULL WAVE DECOMPOSITION RIEMANN SOLVER

    International Nuclear Information System (INIS)

    Anton, Luis; MartI, Jose M; Ibanez, Jose M; Aloy, Miguel A.; Mimica, Petar; Miralles, Juan A.

    2010-01-01

    We obtain renormalized sets of right and left eigenvectors of the flux vector Jacobians of the relativistic MHD equations, which are regular and span a complete basis in any physical state including degenerate ones. The renormalization procedure relies on the characterization of the degeneracy types in terms of the normal and tangential components of the magnetic field to the wave front in the fluid rest frame. Proper expressions of the renormalized eigenvectors in conserved variables are obtained through the corresponding matrix transformations. Our work completes previous analysis that present different sets of right eigenvectors for non-degenerate and degenerate states, and can be seen as a relativistic generalization of earlier work performed in classical MHD. Based on the full wave decomposition (FWD) provided by the renormalized set of eigenvectors in conserved variables, we have also developed a linearized (Roe-type) Riemann solver. Extensive testing against one- and two-dimensional standard numerical problems allows us to conclude that our solver is very robust. When compared with a family of simpler solvers that avoid the knowledge of the full characteristic structure of the equations in the computation of the numerical fluxes, our solver turns out to be less diffusive than HLL and HLLC, and comparable in accuracy to the HLLD solver. The amount of operations needed by the FWD solver makes it less efficient computationally than those of the HLL family in one-dimensional problems. However, its relative efficiency increases in multidimensional simulations.

  2. Legal Sentience and the Problem of the Instant: A Critical Assessment of the Temporal Structure of Precedent and its Implications for Legal Authority

    OpenAIRE

    Wargan, Pawel

    2015-01-01

    This paper assesses the authority of precedent from a phenomenological standpoint. Phenomenology distinguishes between two temporal models. One describes time in an idealised form, as a divisible chain of instants or events. The other looks at lived temporality as fluid and indivisible duration. In the system of precedent, we witness an interaction of both models. The legal order is constructed from slices in time that become the building blocks of future judgments. Precedents are binding for...

  3. ALPS - A LINEAR PROGRAM SOLVER

    Science.gov (United States)

    Viterna, L. A.

    1994-01-01

    Linear programming is a widely-used engineering and management tool. Scheduling, resource allocation, and production planning are all well-known applications of linear programs (LP's). Most LP's are too large to be solved by hand, so over the decades many computer codes for solving LP's have been developed. ALPS, A Linear Program Solver, is a full-featured LP analysis program. ALPS can solve plain linear programs as well as more complicated mixed integer and pure integer programs. ALPS also contains an efficient solution technique for pure binary (0-1 integer) programs. One of the many weaknesses of LP solvers is the lack of interaction with the user. ALPS is a menu-driven program with no special commands or keywords to learn. In addition, ALPS contains a full-screen editor to enter and maintain the LP formulation. These formulations can be written to and read from plain ASCII files for portability. For those less experienced in LP formulation, ALPS contains a problem "parser" which checks the formulation for errors. ALPS creates fully formatted, readable reports that can be sent to a printer or output file. ALPS is written entirely in IBM's APL2/PC product, Version 1.01. The APL2 workspace containing all the ALPS code can be run on any APL2/PC system (AT or 386). On a 32-bit system, this configuration can take advantage of all extended memory. The user can also examine and modify the ALPS code. The APL2 workspace has also been "packed" to be run on any DOS system (without APL2) as a stand-alone "EXE" file, but has limited memory capacity on a 640K system. A numeric coprocessor (80X87) is optional but recommended. The standard distribution medium for ALPS is a 5.25 inch 360K MS-DOS format diskette. IBM, IBM PC and IBM APL2 are registered trademarks of International Business Machines Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

  4. Study of the legal problems raised by the siting of nuclear power stations in artificial islands

    International Nuclear Information System (INIS)

    Hebert, J.; Guieze, J.L.

    1975-01-01

    The creation and operation of a nuclear power station on an artificial island in French waters are governed by domestic law and are subject to two types of procedure: the first concerns erection of the artificial island and the second the control of the public authorities over creation and operation of the nuclear power station. At administrative level, the setting up of an artificial island requires that it be attached to a commune as well as permission for occupancy from the maritime authorities. Furthermore, setting up of a nuclear power station on an artificial island is subject to the licensing procedure for large nuclear installations and to delivery of the licenses required for release of gaseous and liquid radioactive effluents. Given the proximity of the high seas and eventually, the borders of other States, siting of a nuclear power station on an artificial island imposes obligations at international level. These requirements, which concern prevention of transfrontier pollution, stem from the London (1972) and Paris (1974) Conventions on marine pollution. The third party liability regime for a nuclear incident caused by an installation sited in territorial seas is that of the 1960 Paris Convention on third party liability in the nuclear field and the 1963 Brussels Supplementary Convention. Another problem likely to be raised is that of the right of innocent passage of ships near such installations [fr

  5. Problems of Russian construction education in an age of innovation: socio-cultural and legal aspects

    Directory of Open Access Journals (Sweden)

    Pryadko Igor

    2017-01-01

    Full Text Available In this paper we estimate changes of Russian higher education, aimed to incorporate In this paper we estimate changes of Russian higher education, aimed to incorporate the latter in the Bologna process. The analysis of the reforms is given in terms of need in training specialists of the construction industry. The article analyzes the conclusions reached on the issue by some teachers of Russian universities of civil engineering. Among the reasons for concern from the part of the Russian education community, it is called the low level of knowledge about the tasks of re-forms and lack of information regarding measures to improve the educa-tion system. The investigation, in particular, points out that today the main issue of reforming is seen in creation of a single European intellectual space. At the same time, the questionnaire showed that the achievement of the stated purpose is prevented by the following factors: low level of stu-dent-builders in foreign languages and insufficient income. These circums-tances make education abroad almost impossible for most students from Russia and reduce the competitiveness of graduates from Russian universi-ties in labor market of the countries that joined to the Bologna system. The authors of the article pay special attention to the needs of executives of construction firms in qualified specialists. Most of the experts note the iso-lation of universities from solving problems of building practice, a notice-able lag of the national educational system from the western ones in train-ing specialists in construction logistics and organization of construction sites.

  6. Nuclear energy as a 'golden bridge'? Constitutional legal problems of the negotiation of the prolongation of the running time against skimming of profits

    International Nuclear Information System (INIS)

    Waldhoff, Christian; Aswege, Hanka von

    2010-01-01

    The coalition agreement of Christian Demographic Union (CDU), Christian Social Union (CSU) and Free Democratic Party (FDP) from 26th October, 2009 characterizes the nuclear energy as a bridge technology. The coalition parties explain to prolong the running times of German nuclear power stations up to a reliable replacement by renewable energies. The conditions for the prolongation of the running times are to be regulated in agreement with energy supply companies. In the contribution under consideration, the authors report on the fiscal legal problems of the skimming of profits. Constitutional legal problems of the earmaking of a skimming of profits as well as a consensual agreement are discussed in this contribution. In the result, a financial constitutionally reliable way for the skimming of added profits due to prolongation of the running time is not evident. The legal earmaking of the duty advent for the promotion of renewable energies increases the constitutional doubts.

  7. Engaging Ocean Grads As Interdisciplinary Professional Problem Solvers: Why Preparing Our Future Ocean Leaders Means Inspiring Them to Look Beyond Their Academic Learning.

    Science.gov (United States)

    Good, L. H.; Erickson, A.

    2016-02-01

    Academic learning and research experiences alone cannot prepare our emerging ocean leaders to take on the challenges facing our oceans. Developing solutions that incorporate environmental and ocean sciences necessitates an interdisciplinary approach, requiring emerging leaders to be able to work in collaborative knowledge to action systems, rather than on micro-discipline islands. Professional and informal learning experiences can enhance graduate marine education by helping learners gain the communication, collaboration, and innovative problem-solving skills necessary for them to interact with peers at the interface of science and policy. These rich experiences can also provide case-based and hands-on opportunities for graduate learners to explore real-world examples of ocean science, policy, and management in action. However, academic programs are often limited in their capacity to offer such experiences as a part of a traditional curriculum. Rather than expecting learners to rely on their academic training, one approach is to encourage and support graduates to seek professional development beyond their university's walls, and think more holistically about their learning as it relates to their career interests. During this session we discuss current thinking around the professional learning needs of emerging ocean leaders, what this means for academic epistemologies, and examine initial evaluation outcomes from activities in our cross-campus consortium model in Monterey Bay, California. This innovative model includes seven regional academic institutions working together to develop an interdisciplinary ocean community and increase access to professional development opportunities to better prepare regional ocean-interested graduate students and early career researchers as future leaders.

  8. PCX, Interior-Point Linear Programming Solver

    International Nuclear Information System (INIS)

    Czyzyk, J.

    2004-01-01

    1 - Description of program or function: PCX solves linear programming problems using the Mehrota predictor-corrector interior-point algorithm. PCX can be called as a subroutine or used in stand-alone mode, with data supplied from an MPS file. The software incorporates modules that can be used separately from the linear programming solver, including a pre-solve routine and data structure definitions. 2 - Methods: The Mehrota predictor-corrector method is a primal-dual interior-point method for linear programming. The starting point is determined from a modified least squares heuristic. Linear systems of equations are solved at each interior-point iteration via a sparse Cholesky algorithm native to the code. A pre-solver is incorporated in the code to eliminate inefficiencies in the user's formulation of the problem. 3 - Restriction on the complexity of the problem: There are no size limitations built into the program. The size of problem solved is limited by RAM and swap space on the user's computer

  9. Parallel linear solvers for simulations of reactor thermal hydraulics

    International Nuclear Information System (INIS)

    Yan, Y.; Antal, S.P.; Edge, B.; Keyes, D.E.; Shaver, D.; Bolotnov, I.A.; Podowski, M.Z.

    2011-01-01

    The state-of-the-art multiphase fluid dynamics code, NPHASE-CMFD, performs multiphase flow simulations in complex domains using implicit nonlinear treatment of the governing equations and in parallel, which is a very challenging environment for the linear solver. The present work illustrates how the Portable, Extensible Toolkit for Scientific Computation (PETSc) and scalable Algebraic Multigrid (AMG) preconditioner from Hypre can be utilized to construct robust and scalable linear solvers for the Newton correction equation obtained from the discretized system of governing conservation equations in NPHASE-CMFD. The overall long-tem objective of this work is to extend the NPHASE-CMFD code into a fully-scalable solver of multiphase flow and heat transfer problems, applicable to both steady-state and stiff time-dependent phenomena in complete fuel assemblies of nuclear reactors and, eventually, the entire reactor core (such as the Virtual Reactor concept envisioned by CASL). This campaign appropriately begins with the linear algebraic equation solver, which is traditionally a bottleneck to scalability in PDE-based codes. The computational complexity of the solver is usually superlinear in problem size, whereas the rest of the code, the “physics” portion, usually has its complexity linear in the problem size. (author)

  10. Microbes: uranium miners, money makers, problem solvers

    International Nuclear Information System (INIS)

    Williamson, A.L.; Payne, R.; Kerr, F.; Hall, S.; Spiers, G.A.

    2010-01-01

    Bioleaching, the microbial dissolution of minerals, is potentially useful in exploiting a variety of ore deposits, including the lower-grade uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario. The metabolism of chemolithotropic bacterium Acidithiobacillus ferrooxidans is dependent on its ability to derive energy and reducing power from the oxidation of ferrous iron. The characteristics of this bacterium, in particular the ability to oxidize both iron and sulphur with an associated high tolerance of low acidity, allow the organism to contribute significantly to bioleaching processes. Under ideal conditions, A. ferrooxidans promotes the oxidation of iron-containing sulphide ore materials, breaking their crystal structure and promoting the dissolution of iron, base metals, as well as uranium, rare earth elements and associated elements of toxicological interest such as arsenic and selenium. The current study documents an overview of the recovery of uranium and rare earth elements to solution, plus investigates the acid generating potential of the solid residues from a series of environmentally controlled, biologically-mediated uranium ore extraction experiments. The findings will be used in the design of larger scale bioleaching experiments to further assess the potential for success of bioleaching as a metallurgical extraction technique potentially leading to minimum maintenance decommissioning strategies for the ore deposits of the Quirke Syncline. (author)

  11. Equipping the Enterprise Interoperability Problem Solver

    NARCIS (Netherlands)

    Oude Luttighuis, Paul; Folmer, Erwin Johan Albert; Charalabidis, Yannis

    2010-01-01

    The maturity of the enterprise interoperability field does not match the importance attached to it by many, both in the public as well as the private community. A host of models, paradigms, designs, standards, methods, and instruments seems to be available, but many of them are only used in rather

  12. Microbes: uranium miners, money makers, problem solvers

    Energy Technology Data Exchange (ETDEWEB)

    Williamson, A.L., E-mail: awilliamson@mirarco.org [MIRARCO, Sudbury, ON (Canada); Laurentian Univ., Sudbury, ON (Canada); Payne, R.; Kerr, F. [Pele Mountain Resources Inc., Toronto, ON (Canada); Hall, S. [Laurentian Univ., Sudbury, ON (Canada); Spiers, G.A. [MIRARCO, Sudbury, ON (Canada); Laurentian Univ., Sudbury, ON (Canada)

    2010-07-01

    Bioleaching, the microbial dissolution of minerals, is potentially useful in exploiting a variety of ore deposits, including the lower-grade uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario. The metabolism of chemolithotropic bacterium Acidithiobacillus ferrooxidans is dependent on its ability to derive energy and reducing power from the oxidation of ferrous iron. The characteristics of this bacterium, in particular the ability to oxidize both iron and sulphur with an associated high tolerance of low acidity, allow the organism to contribute significantly to bioleaching processes. Under ideal conditions, A. ferrooxidans promotes the oxidation of iron-containing sulphide ore materials, breaking their crystal structure and promoting the dissolution of iron, base metals, as well as uranium, rare earth elements and associated elements of toxicological interest such as arsenic and selenium. The current study documents an overview of the recovery of uranium and rare earth elements to solution, plus investigates the acid generating potential of the solid residues from a series of environmentally controlled, biologically-mediated uranium ore extraction experiments. The findings will be used in the design of larger scale bioleaching experiments to further assess the potential for success of bioleaching as a metallurgical extraction technique potentially leading to minimum maintenance decommissioning strategies for the ore deposits of the Quirke Syncline. (author)

  13. Molecular biology problem solver: a laboratory guide

    National Research Council Canada - National Science Library

    Gerstein, Alan S

    2001-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi Chapter 1. Preparing for Success in the Laboratory Phillip P. Franciskovich . . . . . . . . . . . . . . . . . . . . . . . . 1 Chapter 2. Getting What You Need...

  14. Refined isogeometric analysis for a preconditioned conjugate gradient solver

    KAUST Repository

    Garcia, Daniel

    2018-02-12

    Starting from a highly continuous Isogeometric Analysis (IGA) discretization, refined Isogeometric Analysis (rIGA) introduces C0 hyperplanes that act as separators for the direct LU factorization solver. As a result, the total computational cost required to solve the corresponding system of equations using a direct LU factorization solver dramatically reduces (up to a factor of 55) Garcia et al. (2017). At the same time, rIGA enriches the IGA spaces, thus improving the best approximation error. In this work, we extend the complexity analysis of rIGA to the case of iterative solvers. We build an iterative solver as follows: we first construct the Schur complements using a direct solver over small subdomains (macro-elements). We then assemble those Schur complements into a global skeleton system. Subsequently, we solve this system iteratively using Conjugate Gradients (CG) with an incomplete LU (ILU) preconditioner. For a 2D Poisson model problem with a structured mesh and a uniform polynomial degree of approximation, rIGA achieves moderate savings with respect to IGA in terms of the number of Floating Point Operations (FLOPs) and computational time (in seconds) required to solve the resulting system of linear equations. For instance, for a mesh with four million elements and polynomial degree p=3, the iterative solver is approximately 2.6 times faster (in time) when applied to the rIGA system than to the IGA one. These savings occur because the skeleton rIGA system contains fewer non-zero entries than the IGA one. The opposite situation occurs for 3D problems, and as a result, 3D rIGA discretizations provide no gains with respect to their IGA counterparts when considering iterative solvers.

  15. T2CG1, a package of preconditioned conjugate gradient solvers for TOUGH2

    International Nuclear Information System (INIS)

    Moridis, G.; Pruess, K.; Antunez, E.

    1994-03-01

    Most of the computational work in the numerical simulation of fluid and heat flows in permeable media arises in the solution of large systems of linear equations. The simplest technique for solving such equations is by direct methods. However, because of large storage requirements and accumulation of roundoff errors, the application of direct solution techniques is limited, depending on matrix bandwidth, to systems of a few hundred to at most a few thousand simultaneous equations. T2CG1, a package of preconditioned conjugate gradient solvers, has been added to TOUGH2 to complement its direct solver and significantly increase the size of problems tractable on PCs. T2CG1 includes three different solvers: a Bi-Conjugate Gradient (BCG) solver, a Bi-Conjugate Gradient Squared (BCGS) solver, and a Generalized Minimum Residual (GMRES) solver. Results from six test problems with up to 30,000 equations show that T2CG1 (1) is significantly (and invariably) faster and requires far less memory than the MA28 direct solver, (2) it makes possible the solution of very large three-dimensional problems on PCs, and (3) that the BCGS solver is the fastest of the three in the tested problems. Sample problems are presented related to heat and fluid flow at Yucca Mountain and WIPP, environmental remediation by the Thermal Enhanced Vapor Extraction System, and geothermal resources

  16. Analysis of surveying and legal problems in granting right-of-way and expropriation for the purpose of locating technical infrastructure

    Science.gov (United States)

    Trembecka, Anna

    2016-06-01

    A condition which determines the location of technical infrastructure is an entrepreneur holding the right to use the property for construction purposes. Currently, there are parallel separate legal forms allowing the use of a real property for the purpose of locating transmission lines, i.e. transmission easement (right-of-way) established under the civil law and expropriation by limiting the rights to a property under the administrative law. The aim of the study is to compare these forms conferring the right to use real properties and to analyze the related surveying and legal problems occurring in practice. The research thesis of the article is ascertainment that the current legal provisions for establishing legal titles to a property in order to locate transmission lines need to be amended. The conducted study regarded legal conditions, extent of expropriation and granting right-of-way in the city of Krakow, as well as the problems associated with the ambiguous wording of the legal regulations. Part of the research was devoted to the form of rights to land in order to carry out similar projects in some European countries (France, Czech Republic, Germany, Sweden). The justification for the analysis of these issues is dictated by the scale of practical use of the aforementioned forms of rights to land in order to locate technical infrastructure. Over the period of 2011-2014, 651 agreements were concluded on granting transmission right-of-way for 967 cadastral parcels owned by the city of Krakow, and 105 expropriation decisions were issued, limiting the use of real properties in Krakow.

  17. Problems of Legal Regulation of Criminal Responsibility for Illegal Plunder and Circulation of Especially Valuable Strains of Cattle

    Directory of Open Access Journals (Sweden)

    Bavsun M. V.

    2014-10-01

    Full Text Available The article deals with the disputable issues in legal regulation of criminal responsibility for plunder and circulation of especially valuable strains of wild cattle, acting as a subject of legal and criminal protection, Art. 258.1 of the RF CC (Criminal Code of the Russian Federation. As a conclusion the author offers the variant of proposals for improvement of legislative construction of the norm considered on the ground of the analysis conducted

  18. High-Performance Small-Scale Solvers for Moving Horizon Estimation

    DEFF Research Database (Denmark)

    Frison, Gianluca; Vukov, Milan; Poulsen, Niels Kjølstad

    2015-01-01

    implementation techniques focusing on small-scale problems. The proposed MHE solver is implemented using custom linear algebra routines and is compared against implementations using BLAS libraries. Additionally, the MHE solver is interfaced to a code generation tool for nonlinear model predictive control (NMPC...

  19. Investigation on the Use of a Multiphase Eulerian CFD solver to simulate breaking waves

    DEFF Research Database (Denmark)

    Tomaselli, Pietro D.; Christensen, Erik Damgaard

    2015-01-01

    investigation on a CFD model capable of handling this problem. The model is based on a solver, available in the open-source CFD toolkit OpenFOAM, which combines the Eulerian multi-fluid approach for dispersed flows with a numerical interface sharpening method. The solver, enhanced with additional formulations...

  20. Optimising a parallel conjugate gradient solver

    Energy Technology Data Exchange (ETDEWEB)

    Field, M.R. [O`Reilly Institute, Dublin (Ireland)

    1996-12-31

    This work arises from the introduction of a parallel iterative solver to a large structural analysis finite element code. The code is called FEX and it was developed at Hitachi`s Mechanical Engineering Laboratory. The FEX package can deal with a large range of structural analysis problems using a large number of finite element techniques. FEX can solve either stress or thermal analysis problems of a range of different types from plane stress to a full three-dimensional model. These problems can consist of a number of different materials which can be modelled by a range of material models. The structure being modelled can have the load applied at either a point or a surface, or by a pressure, a centrifugal force or just gravity. Alternatively a thermal load can be applied with a given initial temperature. The displacement of the structure can be constrained by having a fixed boundary or by prescribing the displacement at a boundary.

  1. Iterative solvers in forming process simulations

    NARCIS (Netherlands)

    van den Boogaard, Antonius H.; Rietman, Bert; Huetink, Han

    1998-01-01

    The use of iterative solvers in implicit forming process simulations is studied. The time and memory requirements are compared with direct solvers and assessed in relation with the rest of the Newton-Raphson iteration process. It is shown that conjugate gradient{like solvers with a proper

  2. Fast Multipole-Based Elliptic PDE Solver and Preconditioner

    KAUST Repository

    Ibeid, Huda

    2016-01-01

    extrapolated scalability. Fast multipole methods (FMM) were originally developed for accelerating N-body problems for particle-based methods in astrophysics and molecular dynamics. FMM is more than an N-body solver, however. Recent efforts to view the FMM

  3. LAPACKrc: Fast linear algebra kernels/solvers for FPGA accelerators

    International Nuclear Information System (INIS)

    Gonzalez, Juan; Nunez, Rafael C

    2009-01-01

    We present LAPACKrc, a family of FPGA-based linear algebra solvers able to achieve more than 100x speedup per commodity processor on certain problems. LAPACKrc subsumes some of the LAPACK and ScaLAPACK functionalities, and it also incorporates sparse direct and iterative matrix solvers. Current LAPACKrc prototypes demonstrate between 40x-150x speedup compared against top-of-the-line hardware/software systems. A technology roadmap is in place to validate current performance of LAPACKrc in HPC applications, and to increase the computational throughput by factors of hundreds within the next few years.

  4. Fast Laplace solver approach to pore-scale permeability

    Science.gov (United States)

    Arns, C. H.; Adler, P. M.

    2018-02-01

    We introduce a powerful and easily implemented method to calculate the permeability of porous media at the pore scale using an approximation based on the Poiseulle equation to calculate permeability to fluid flow with a Laplace solver. The method consists of calculating the Euclidean distance map of the fluid phase to assign local conductivities and lends itself naturally to the treatment of multiscale problems. We compare with analytical solutions as well as experimental measurements and lattice Boltzmann calculations of permeability for Fontainebleau sandstone. The solver is significantly more stable than the lattice Boltzmann approach, uses less memory, and is significantly faster. Permeabilities are in excellent agreement over a wide range of porosities.

  5. Advanced Algebraic Multigrid Solvers for Subsurface Flow Simulation

    KAUST Repository

    Chen, Meng-Huo

    2015-09-13

    In this research we are particularly interested in extending the robustness of multigrid solvers to encounter complex systems related to subsurface reservoir applications for flow problems in porous media. In many cases, the step for solving the pressure filed in subsurface flow simulation becomes a bottleneck for the performance of the simulator. For solving large sparse linear system arising from MPFA discretization, we choose multigrid methods as the linear solver. The possible difficulties and issues will be addressed and the corresponding remedies will be studied. As the multigrid methods are used as the linear solver, the simulator can be parallelized (although not trivial) and the high-resolution simulation become feasible, the ultimately goal which we desire to achieve.

  6. An efficient spectral crystal plasticity solver for GPU architectures

    Science.gov (United States)

    Malahe, Michael

    2018-03-01

    We present a spectral crystal plasticity (CP) solver for graphics processing unit (GPU) architectures that achieves a tenfold increase in efficiency over prior GPU solvers. The approach makes use of a database containing a spectral decomposition of CP simulations performed using a conventional iterative solver over a parameter space of crystal orientations and applied velocity gradients. The key improvements in efficiency come from reducing global memory transactions, exposing more instruction-level parallelism, reducing integer instructions and performing fast range reductions on trigonometric arguments. The scheme also makes more efficient use of memory than prior work, allowing for larger problems to be solved on a single GPU. We illustrate these improvements with a simulation of 390 million crystal grains on a consumer-grade GPU, which executes at a rate of 2.72 s per strain step.

  7. A generalized gyrokinetic Poisson solver

    International Nuclear Information System (INIS)

    Lin, Z.; Lee, W.W.

    1995-03-01

    A generalized gyrokinetic Poisson solver has been developed, which employs local operations in the configuration space to compute the polarization density response. The new technique is based on the actual physical process of gyrophase-averaging. It is useful for nonlocal simulations using general geometry equilibrium. Since it utilizes local operations rather than the global ones such as FFT, the new method is most amenable to massively parallel algorithms

  8. Innovative Use of the Law to Address Complex Global Health Problems Comment on "The Legal Strength of International Health Instruments - What It Brings toGlobal Health Governance?"

    Science.gov (United States)

    Walls, Helen L; Ooms, Gorik

    2017-05-20

    Addressing the increasingly globalised determinants of many important problems affecting human health is a complex task requiring collective action. We suggest that part of the solution to addressing intractable global health issues indeed lies with the role of new legal instruments in the form of globally binding treaties, as described in the recent article of Nikogosian and Kickbusch. However, in addition to the use of international law to develop new treaties, another part of the solution may lie in innovative use of existing legal instruments. A 2015 court ruling in The Hague, which ordered the Dutch government to cut greenhouse gas emissions by at least 25% within five years, complements this perspective, suggesting a way forward for addressing global health problems that critically involves civil society and innovative use of existing domestic legal instruments. © 2017 The Author(s); Published by Kerman University of Medical Sciences. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  9. A General Symbolic PDE Solver Generator: Explicit Schemes

    Directory of Open Access Journals (Sweden)

    K. Sheshadri

    2003-01-01

    Full Text Available A symbolic solver generator to deal with a system of partial differential equations (PDEs in functions of an arbitrary number of variables is presented; it can also handle arbitrary domains (geometries of the independent variables. Given a system of PDEs, the solver generates a set of explicit finite-difference methods to any specified order, and a Fourier stability criterion for each method. For a method that is stable, an iteration function is generated symbolically using the PDE and its initial and boundary conditions. This iteration function is dynamically generated for every PDE problem, and its evaluation provides a solution to the PDE problem. A C++/Fortran 90 code for the iteration function is generated using the MathCode system, which results in a performance gain of the order of a thousand over Mathematica, the language that has been used to code the solver generator. Examples of stability criteria are presented that agree with known criteria; examples that demonstrate the generality of the solver and the speed enhancement of the generated C++ and Fortran 90 codes are also presented.

  10. Implementation and testing of a multivariate inverse radiation transport solver

    International Nuclear Information System (INIS)

    Mattingly, John; Mitchell, Dean J.

    2012-01-01

    Detection, identification, and characterization of special nuclear materials (SNM) all face the same basic challenge: to varying degrees, each must infer the presence, composition, and configuration of the SNM by analyzing a set of measured radiation signatures. Solutions to this problem implement inverse radiation transport methods. Given a set of measured radiation signatures, inverse radiation transport estimates properties of the source terms and transport media that are consistent with those signatures. This paper describes one implementation of a multivariate inverse radiation transport solver. The solver simultaneously analyzes gamma spectrometry and neutron multiplicity measurements to fit a one-dimensional radiation transport model with variable layer thicknesses using nonlinear regression. The solver's essential components are described, and its performance is illustrated by application to benchmark experiments conducted with plutonium metal. - Highlights: ► Inverse problems, specifically applied to identifying and characterizing radiation sources . ► Radiation transport. ► Analysis of gamma spectroscopy and neutron multiplicity counting measurements. ► Experimental testing of the inverse solver against measurements of plutonium.

  11. Graph Grammar-Based Multi-Frontal Parallel Direct Solver for Two-Dimensional Isogeometric Analysis

    KAUST Repository

    Kuźnik, Krzysztof; Paszyński, Maciej; Calo, Victor M.

    2012-01-01

    at parent nodes and eliminates rows corresponding to fully assembled degrees of freedom. Finally, there are graph grammar productions responsible for root problem solution and recursive backward substitutions. Expressing the solver algorithm by graph grammar

  12. High order Poisson Solver for unbounded flows

    DEFF Research Database (Denmark)

    Hejlesen, Mads Mølholm; Rasmussen, Johannes Tophøj; Chatelain, Philippe

    2015-01-01

    This paper presents a high order method for solving the unbounded Poisson equation on a regular mesh using a Green’s function solution. The high order convergence was achieved by formulating mollified integration kernels, that were derived from a filter regularisation of the solution field....... The method was implemented on a rectangular domain using fast Fourier transforms (FFT) to increase computational efficiency. The Poisson solver was extended to directly solve the derivatives of the solution. This is achieved either by including the differential operator in the integration kernel...... the equations of fluid mechanics as an example, but can be used in many physical problems to solve the Poisson equation on a rectangular unbounded domain. For the two-dimensional case we propose an infinitely smooth test function which allows for arbitrary high order convergence. Using Gaussian smoothing...

  13. Actual legal questions and problems of the free access to information, especially in the environmental protection; Aktuelle Rechtsfragen und Probleme des freien Informationszugangs, insbesondere im Umweltschutz

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Meinhard (ed.)

    2010-07-01

    Within the 26th Trier colloquium on the law governing environmental protection and technology at 5th to 7th September, 2010 in Trier (Federal Republic of Germany), the following lectures were held: (1) The environmental law in the light of federalism and Europeanization (Hans-Juergen Papier); (2) Information rights in the EU (Astrid Epiney); (3) Environmental policy by freedom of information (Friedrich Schoch); (4) The legal framework for the opening of the access to information as well as the appearance of accessible information under special consideration of the environmental information Directive 2003/4/EG and its implementation in the German Law (Joern Axel Kaemmerer); (5) The utilization of electronic media: REACh data bases, publication of authorizing procedures in the Internet and geo data mediation such as google maps (Indra Spiecker); (6) Protection position of companies in the right of access to information. The protection of business secrets and commercial confidentialities as well as application dossiers in the European and German law (Matthias Rossi); (7) Limited protection of business secrets and commercial confidentialities as a part of genetic engineering legal approval procedures (Hartwig Stiebler); (8) The NRW pipeline cadastre (Alexander Schink); (9) Legal protection by European and national courts under consideration of the European Ombudsman in his function in securing the access of information (Sabine Schlacke).

  14. Motivation, Challenge, and Opportunity of Successful Solvers on an Innovation Platform

    DEFF Research Database (Denmark)

    Hossain, Mokter

    2017-01-01

    . The main motivational factors of successful solvers engaged in problem solving are money, learning, fun, sense of achievement, passion, and networking. Major challenges solvers face include unclear or insufficient problem description, lack of option for communication, language barrier, time zone...... other experts, the ability to work in a diverse environment, options of work after retirement and from distant locations, and a new source of income....

  15. Motivations, Challenges, and Opportunities of Successful Solvers on an Innovation Intermediary Platform

    DEFF Research Database (Denmark)

    Hossain, Mokter

    2018-01-01

    . The main motivational factors of successful solvers engaged in problem solving are money, learning, fun, sense of achievement, passion, and networking. Major challenges solvers face include unclear or insufficient problem description, lack of option for communication, language barrier, time zone...... other experts, the ability to work in a diverse environment, options of work after retirement and from distant locations, and a new source of income....

  16. An Investigation of the Performance of the Colored Gauss-Seidel Solver on CPU and GPU

    International Nuclear Information System (INIS)

    Yoon, Jong Seon; Choi, Hyoung Gwon; Jeon, Byoung Jin

    2017-01-01

    The performance of the colored Gauss–Seidel solver on CPU and GPU was investigated for the two- and three-dimensional heat conduction problems by using different mesh sizes. The heat conduction equation was discretized by the finite difference method and finite element method. The CPU yielded good performance for small problems but deteriorated when the total memory required for computing was larger than the cache memory for large problems. In contrast, the GPU performed better as the mesh size increased because of the latency hiding technique. Further, GPU computation by the colored Gauss–Siedel solver was approximately 7 times that by the single CPU. Furthermore, the colored Gauss–Seidel solver was found to be approximately twice that of the Jacobi solver when parallel computing was conducted on the GPU.

  17. An Investigation of the Performance of the Colored Gauss-Seidel Solver on CPU and GPU

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jong Seon; Choi, Hyoung Gwon [Seoul Nat’l Univ. of Science and Technology, Seoul (Korea, Republic of); Jeon, Byoung Jin [Yonsei Univ., Seoul (Korea, Republic of)

    2017-02-15

    The performance of the colored Gauss–Seidel solver on CPU and GPU was investigated for the two- and three-dimensional heat conduction problems by using different mesh sizes. The heat conduction equation was discretized by the finite difference method and finite element method. The CPU yielded good performance for small problems but deteriorated when the total memory required for computing was larger than the cache memory for large problems. In contrast, the GPU performed better as the mesh size increased because of the latency hiding technique. Further, GPU computation by the colored Gauss–Siedel solver was approximately 7 times that by the single CPU. Furthermore, the colored Gauss–Seidel solver was found to be approximately twice that of the Jacobi solver when parallel computing was conducted on the GPU.

  18. Migration of vectorized iterative solvers to distributed memory architectures

    Energy Technology Data Exchange (ETDEWEB)

    Pommerell, C. [AT& T Bell Labs., Murray Hill, NJ (United States); Ruehl, R. [CSCS-ETH, Manno (Switzerland)

    1994-12-31

    Both necessity and opportunity motivate the use of high-performance computers for iterative linear solvers. Necessity results from the size of the problems being solved-smaller problems are often better handled by direct methods. Opportunity arises from the formulation of the iterative methods in terms of simple linear algebra operations, even if this {open_quote}natural{close_quotes} parallelism is not easy to exploit in irregularly structured sparse matrices and with good preconditioners. As a result, high-performance implementations of iterative solvers have attracted a lot of interest in recent years. Most efforts are geared to vectorize or parallelize the dominating operation-structured or unstructured sparse matrix-vector multiplication, or to increase locality and parallelism by reformulating the algorithm-reducing global synchronization in inner products or local data exchange in preconditioners. Target architectures for iterative solvers currently include mostly vector supercomputers and architectures with one or few optimized (e.g., super-scalar and/or super-pipelined RISC) processors and hierarchical memory systems. More recently, parallel computers with physically distributed memory and a better price/performance ratio have been offered by vendors as a very interesting alternative to vector supercomputers. However, programming comfort on such distributed memory parallel processors (DMPPs) still lags behind. Here the authors are concerned with iterative solvers and their changing computing environment. In particular, they are considering migration from traditional vector supercomputers to DMPPs. Application requirements force one to use flexible and portable libraries. They want to extend the portability of iterative solvers rather than reimplementing everything for each new machine, or even for each new architecture.

  19. Approximate Riemann solver for the two-fluid plasma model

    International Nuclear Information System (INIS)

    Shumlak, U.; Loverich, J.

    2003-01-01

    An algorithm is presented for the simulation of plasma dynamics using the two-fluid plasma model. The two-fluid plasma model is more general than the magnetohydrodynamic (MHD) model often used for plasma dynamic simulations. The two-fluid equations are derived in divergence form and an approximate Riemann solver is developed to compute the fluxes of the electron and ion fluids at the computational cell interfaces and an upwind characteristic-based solver to compute the electromagnetic fields. The source terms that couple the fluids and fields are treated implicitly to relax the stiffness. The algorithm is validated with the coplanar Riemann problem, Langmuir plasma oscillations, and the electromagnetic shock problem that has been simulated with the MHD plasma model. A numerical dispersion relation is also presented that demonstrates agreement with analytical plasma waves

  20. Nonlinear Multigrid solver exploiting AMGe Coarse Spaces with Approximation Properties

    DEFF Research Database (Denmark)

    Christensen, Max la Cour; Villa, Umberto; Engsig-Karup, Allan Peter

    The paper introduces a nonlinear multigrid solver for mixed finite element discretizations based on the Full Approximation Scheme (FAS) and element-based Algebraic Multigrid (AMGe). The main motivation to use FAS for unstructured problems is the guaranteed approximation property of the AMGe coarse...... properties of the coarse spaces. With coarse spaces with approximation properties, our FAS approach on unstructured meshes has the ability to be as powerful/successful as FAS on geometrically refined meshes. For comparison, Newton’s method and Picard iterations with an inner state-of-the-art linear solver...... are compared to FAS on a nonlinear saddle point problem with applications to porous media flow. It is demonstrated that FAS is faster than Newton’s method and Picard iterations for the experiments considered here. Due to the guaranteed approximation properties of our AMGe, the coarse spaces are very accurate...

  1. Jump as Far as You Can [Problem Solvers: Problem

    Science.gov (United States)

    Bofferding, Laura; Yigit, Melike

    2013-01-01

    The standing long jump was an Olympic event until 1912. In 1904, Ray Ewry set the world record for the longest standing long jump, which was about 11.5 feet, or 138 inches. Although the standing long jump is no longer an Olympic event, the Norwegians still include it in their National Competition, and Arne Tvervaag set a new world record at about…

  2. DEMOCRATIZAÇÃO DA JUSTIÇA: A APRENDIZAGEM BASEADA EM PROBLEMAS APLICADA À PRÁTICA JURÍDICA CURRICULAR | JUSTICE DEMOCRATIZATION: THE PROBLEM BASED LEARNING APPLIED TO THE LEGAL PRACTICE IN LAW COURSES

    Directory of Open Access Journals (Sweden)

    Roberto Muhájir Rahnemay Rabbani

    2016-08-01

    Full Text Available This study reports an experience on legal services brought by the Federal University of Rio Grande do Norte, Brazil, Caicó Campus, approaching this institution to the region community. Through real case studies, the students were motivated to conduct a legal and juridical analysis, and had to present the results to the consultants and the professors. The students were entrusted to give legal opinion and explain the procedural stages on the cases presented by the community. The methodology used was the empirical research through qualitative and quantitative methods, by applying questionnaires to users of the legal practice and the students of the Legal Assistance courses on the service and the use of Problem-Based Learning. The results demonstrate a high level of satisfaction by users and students, that ensured that the used methodology enabled their best qualification for the labor market.

  3. Multiscale Universal Interface: A concurrent framework for coupling heterogeneous solvers

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yu-Hang, E-mail: yuhang_tang@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI (United States); Kudo, Shuhei, E-mail: shuhei-kudo@outlook.jp [Graduate School of System Informatics, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501 (Japan); Bian, Xin, E-mail: xin_bian@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI (United States); Li, Zhen, E-mail: zhen_li@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI (United States); Karniadakis, George Em, E-mail: george_karniadakis@brown.edu [Division of Applied Mathematics, Brown University, Providence, RI (United States); Collaboratory on Mathematics for Mesoscopic Modeling of Materials, Pacific Northwest National Laboratory, Richland, WA 99354 (United States)

    2015-09-15

    Graphical abstract: - Abstract: Concurrently coupled numerical simulations using heterogeneous solvers are powerful tools for modeling multiscale phenomena. However, major modifications to existing codes are often required to enable such simulations, posing significant difficulties in practice. In this paper we present a C++ library, i.e. the Multiscale Universal Interface (MUI), which is capable of facilitating the coupling effort for a wide range of multiscale simulations. The library adopts a header-only form with minimal external dependency and hence can be easily dropped into existing codes. A data sampler concept is introduced, combined with a hybrid dynamic/static typing mechanism, to create an easily customizable framework for solver-independent data interpretation. The library integrates MPI MPMD support and an asynchronous communication protocol to handle inter-solver information exchange irrespective of the solvers' own MPI awareness. Template metaprogramming is heavily employed to simultaneously improve runtime performance and code flexibility. We validated the library by solving three different multiscale problems, which also serve to demonstrate the flexibility of the framework in handling heterogeneous models and solvers. In the first example, a Couette flow was simulated using two concurrently coupled Smoothed Particle Hydrodynamics (SPH) simulations of different spatial resolutions. In the second example, we coupled the deterministic SPH method with the stochastic Dissipative Particle Dynamics (DPD) method to study the effect of surface grafting on the hydrodynamics properties on the surface. In the third example, we consider conjugate heat transfer between a solid domain and a fluid domain by coupling the particle-based energy-conserving DPD (eDPD) method with the Finite Element Method (FEM)

  4. Decision Engines for Software Analysis Using Satisfiability Modulo Theories Solvers

    Science.gov (United States)

    Bjorner, Nikolaj

    2010-01-01

    The area of software analysis, testing and verification is now undergoing a revolution thanks to the use of automated and scalable support for logical methods. A well-recognized premise is that at the core of software analysis engines is invariably a component using logical formulas for describing states and transformations between system states. The process of using this information for discovering and checking program properties (including such important properties as safety and security) amounts to automatic theorem proving. In particular, theorem provers that directly support common software constructs offer a compelling basis. Such provers are commonly called satisfiability modulo theories (SMT) solvers. Z3 is a state-of-the-art SMT solver. It is developed at Microsoft Research. It can be used to check the satisfiability of logical formulas over one or more theories such as arithmetic, bit-vectors, lists, records and arrays. The talk describes some of the technology behind modern SMT solvers, including the solver Z3. Z3 is currently mainly targeted at solving problems that arise in software analysis and verification. It has been applied to various contexts, such as systems for dynamic symbolic simulation (Pex, SAGE, Vigilante), for program verification and extended static checking (Spec#/Boggie, VCC, HAVOC), for software model checking (Yogi, SLAM), model-based design (FORMULA), security protocol code (F7), program run-time analysis and invariant generation (VS3). We will describe how it integrates support for a variety of theories that arise naturally in the context of the applications. There are several new promising avenues and the talk will touch on some of these and the challenges related to SMT solvers. Proceedings

  5. Legal protection of the right to work and employment for persons with mental health problems: a review of legislation across the world.

    Science.gov (United States)

    Nardodkar, Renuka; Pathare, Soumitra; Ventriglio, Antonio; Castaldelli-Maia, João; Javate, Kenneth R; Torales, Julio; Bhugra, Dinesh

    2016-08-01

    The right to work and employment is indispensable for social integration of persons with mental health problems. This study examined whether existing laws pose structural barriers in the realization of right to work and employment of persons with mental health problems across the world. It reviewed disability-specific, human rights legislation, and labour laws of all UN Member States in the context of Article 27 of the UN Convention on the Rights of Persons with Disabilities (CRPD). It wes found that laws in 62% of countries explicitly mention mental disability/impairment/illness in the definition of disability. In 64% of countries, laws prohibit discrimination against persons with mental health during recruitment; in one-third of countries laws prohibit discontinuation of employment. More than half (56%) the countries have laws in place which offer access to reasonable accommodation in the workplace. In 59% of countries laws promote employment of persons with mental health problems through different affirmative actions. Nearly 50 years after the adoption of the International Covenant on Economic, Social, and Cultural Rights and 10 years after the adoption of CRPD by the UN General Assembly, legal discrimination against persons with mental health problems continues to exist globally. Countries and policy-makers need to implement legislative measures to ensure non-discrimination of persons with mental health problems during employment.

  6. Fast linear solver for radiative transport equation with multiple right hand sides in diffuse optical tomography

    International Nuclear Information System (INIS)

    Jia, Jingfei; Kim, Hyun K.; Hielscher, Andreas H.

    2015-01-01

    It is well known that radiative transfer equation (RTE) provides more accurate tomographic results than its diffusion approximation (DA). However, RTE-based tomographic reconstruction codes have limited applicability in practice due to their high computational cost. In this article, we propose a new efficient method for solving the RTE forward problem with multiple light sources in an all-at-once manner instead of solving it for each source separately. To this end, we introduce here a novel linear solver called block biconjugate gradient stabilized method (block BiCGStab) that makes full use of the shared information between different right hand sides to accelerate solution convergence. Two parallelized block BiCGStab methods are proposed for additional acceleration under limited threads situation. We evaluate the performance of this algorithm with numerical simulation studies involving the Delta–Eddington approximation to the scattering phase function. The results show that the single threading block RTE solver proposed here reduces computation time by a factor of 1.5–3 as compared to the traditional sequential solution method and the parallel block solver by a factor of 1.5 as compared to the traditional parallel sequential method. This block linear solver is, moreover, independent of discretization schemes and preconditioners used; thus further acceleration and higher accuracy can be expected when combined with other existing discretization schemes or preconditioners. - Highlights: • We solve the multiple-right-hand-side problem in DOT with a block BiCGStab method. • We examine the CPU times of the block solver and the traditional sequential solver. • The block solver is faster than the sequential solver by a factor of 1.5–3.0. • Multi-threading block solvers give additional speedup under limited threads situation.

  7. NONLINEAR MULTIGRID SOLVER EXPLOITING AMGe COARSE SPACES WITH APPROXIMATION PROPERTIES

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, Max La Cour [Technical Univ. of Denmark, Lyngby (Denmark); Villa, Umberto E. [Univ. of Texas, Austin, TX (United States); Engsig-Karup, Allan P. [Technical Univ. of Denmark, Lyngby (Denmark); Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-22

    The paper introduces a nonlinear multigrid solver for mixed nite element discretizations based on the Full Approximation Scheme (FAS) and element-based Algebraic Multigrid (AMGe). The main motivation to use FAS for unstruc- tured problems is the guaranteed approximation property of the AMGe coarse spaces that were developed recently at Lawrence Livermore National Laboratory. These give the ability to derive stable and accurate coarse nonlinear discretization problems. The previous attempts (including ones with the original AMGe method, [5, 11]), were less successful due to lack of such good approximation properties of the coarse spaces. With coarse spaces with approximation properties, our FAS approach on un- structured meshes should be as powerful/successful as FAS on geometrically re ned meshes. For comparison, Newton's method and Picard iterations with an inner state-of-the-art linear solver is compared to FAS on a nonlinear saddle point problem with applications to porous media ow. It is demonstrated that FAS is faster than Newton's method and Picard iterations for the experiments considered here. Due to the guaranteed approximation properties of our AMGe, the coarse spaces are very accurate, providing a solver with the potential for mesh-independent convergence on general unstructured meshes.

  8. The impact of improved sparse linear solvers on industrial engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Heroux, M. [Cray Research, Inc., Eagan, MN (United States); Baddourah, M.; Poole, E.L.; Yang, Chao Wu

    1996-12-31

    There are usually many factors that ultimately determine the quality of computer simulation for engineering applications. Some of the most important are the quality of the analytical model and approximation scheme, the accuracy of the input data and the capability of the computing resources. However, in many engineering applications the characteristics of the sparse linear solver are the key factors in determining how complex a problem a given application code can solve. Therefore, the advent of a dramatically improved solver often brings with it dramatic improvements in our ability to do accurate and cost effective computer simulations. In this presentation we discuss the current status of sparse iterative and direct solvers in several key industrial CFD and structures codes, and show the impact that recent advances in linear solvers have made on both our ability to perform challenging simulations and the cost of those simulations. We also present some of the current challenges we have and the constraints we face in trying to improve these solvers. Finally, we discuss future requirements for sparse linear solvers on high performance architectures and try to indicate the opportunities that exist if we can develop even more improvements in linear solver capabilities.

  9. The Clean Development Mechanism as a governance problem. Compensate deficits as well as Europe legal and international legal further progress of climate protection regarding to Copenhagen and Cancun; Der Clean Development Mechanism als Governance-Problem. Steuerungsdefizite sowie europarechtliche und voelkerrechtliche Weiterentwicklungen des Klimaschutzes nach Kopenhagen und Cancun

    Energy Technology Data Exchange (ETDEWEB)

    Ekardt, Felix; Exner, Anne-Katrin [Rostock Univ. (Germany). Forschungsgruppe Nachhaltigkeit und Klimapolitik

    2011-04-15

    The authors of the contribution analyze the developments in law, legal interpretation issues as well as climate political and development political effects of the Clean Development Mechanism (CDM) as an element of transnational climate change law which is associated with the states and emission trading (ETS). In the basic intention CDM shall achieve a climate-neutral reduction of costs of climate policy at the simultaneous promotion of development political goals where industrial countries may provide their global or European targets of reduction in part by means of measures in emerging or developing countries rather than by means of local climate protection. However, the specific CDM projects prove to be questionable with respect to the climate policy and development policy. This also is related to enforcement problems that represent a variant of the general environment legal problem of the latent 'interest identity of inspectors and controlled persons'. The proposed European legal and the possible international (land use related) developments of the CDM since 2013 and currently in Cancun probably will not change essentially the fundamental but intensify it even more. With all that, at the same time a kind of exemplary governance analysis arises in the context of the ETS by means of one essential part of its aspects - as well as generally in the context to the perspectives of climate policy according to Cancun.

  10. The Analysis of Prospects for Derivatives Market Development in Ukraine in View of Solving the Problems of its Normative Legal Regulation

    Directory of Open Access Journals (Sweden)

    Kolodizev Oleg M.

    2016-02-01

    Full Text Available The increased uncertainty in the country’s economy, impossibility of raising capital only by standard financial instruments substantiated the need for such financial innovations as derivatives. The relevance of the suggested topic is justified by the lack of strong legislative framework regulating the market of derivative financial instruments, as well as by significant demand for them in Ukraine. The aim of the article is to analyze the development level of the normative and legal field of trade in the derivatives market as well as the quality of the formed system of main indicators for derivatives trading in Ukraine. The paper identifies the problem, which could be neutralized through the use of derivative financial instruments. The volume and structure of the world and domestic derivatives markets have been analyzed. Based on the analysis of the legal field of regulating the market of derivative financial instruments as well as statistical analysis of its volume and structure, the reasons for the low activity in the considered market have been justified and recommendations to improve the current situation proposed.

  11. The principle of legal certainty in the practice of the European Court of Human Rights and the quality problems of the criminal legislation of Ukraine

    Directory of Open Access Journals (Sweden)

    М. І. Панов

    2015-03-01

    Full Text Available The article provides an outline of the principle of «legal certainty» in the practice of the European Court of Human Rights, shows its influence on the quality assurance of national criminal law and the principle of «rule of law» and «law» in judicial practice in criminal cases. It is noted that the category of «quality of the law on criminal responsibility» is closely connected with the principle of «legal certainty», includes a wide range of issues, the most important of which is the problem of the accuracy of criminal law. The content of this multifaceted category in terms of its various aspects: epistemological, logical, linguistic, pragmatic and on this basis are considered essential features and properties of the accuracy of criminal law, a necessary condition for ensuring the quality of the law on criminal responsibility. At the same time found out some shortcomings of the current penal legislation, proposals are being made to eliminate them.

  12. Legal Problems of Realization of the Principle of “Good Faith” in the Course of Bankruptcy

    Directory of Open Access Journals (Sweden)

    Yuliya V. Sakharova

    2017-05-01

    Full Text Available This article is about research problems of realization of the principle of conscientiousness in relation to procedures of insolvency (bankruptcy. The Author considers problems of determination of category “conscientiousness”, the questions of criteria to determine the good faith of the trustee, the criteria of “sufficiency” in his actions, good faith in complying with the statute of limitations in the procedures of bankruptcy, as well as violation of the principle of good faith with the liquidator failure to take appropriate action to challenge the debtor's contracts.​

  13. Scalable parallel prefix solvers for discrete ordinates transport

    International Nuclear Information System (INIS)

    Pautz, S.; Pandya, T.; Adams, M.

    2009-01-01

    The well-known 'sweep' algorithm for inverting the streaming-plus-collision term in first-order deterministic radiation transport calculations has some desirable numerical properties. However, it suffers from parallel scaling issues caused by a lack of concurrency. The maximum degree of concurrency, and thus the maximum parallelism, grows more slowly than the problem size for sweeps-based solvers. We investigate a new class of parallel algorithms that involves recasting the streaming-plus-collision problem in prefix form and solving via cyclic reduction. This method, although computationally more expensive at low levels of parallelism than the sweep algorithm, offers better theoretical scalability properties. Previous work has demonstrated this approach for one-dimensional calculations; we show how to extend it to multidimensional calculations. Notably, for multiple dimensions it appears that this approach is limited to long-characteristics discretizations; other discretizations cannot be cast in prefix form. We implement two variants of the algorithm within the radlib/SCEPTRE transport code library at Sandia National Laboratories and show results on two different massively parallel systems. Both the 'forward' and 'symmetric' solvers behave similarly, scaling well to larger degrees of parallelism then sweeps-based solvers. We do observe some issues at the highest levels of parallelism (relative to the system size) and discuss possible causes. We conclude that this approach shows good potential for future parallel systems, but the parallel scalability will depend heavily on the architecture of the communication networks of these systems. (authors)

  14. Newton-Krylov-BDDC solvers for nonlinear cardiac mechanics

    KAUST Repository

    Pavarino, L.F.; Scacchi, S.; Zampini, Stefano

    2015-01-01

    The aim of this work is to design and study a Balancing Domain Decomposition by Constraints (BDDC) solver for the nonlinear elasticity system modeling the mechanical deformation of cardiac tissue. The contraction–relaxation process in the myocardium is induced by the generation and spread of the bioelectrical excitation throughout the tissue and it is mathematically described by the coupling of cardiac electro-mechanical models consisting of systems of partial and ordinary differential equations. In this study, the discretization of the electro-mechanical models is performed by Q1 finite elements in space and semi-implicit finite difference schemes in time, leading to the solution of a large-scale linear system for the bioelectrical potentials and a nonlinear system for the mechanical deformation at each time step of the simulation. The parallel mechanical solver proposed in this paper consists in solving the nonlinear system with a Newton-Krylov-BDDC method, based on the parallel solution of local mechanical problems and a coarse problem for the so-called primal unknowns. Three-dimensional parallel numerical tests on different machines show that the proposed parallel solver is scalable in the number of subdomains, quasi-optimal in the ratio of subdomain to mesh sizes, and robust with respect to tissue anisotropy.

  15. Newton-Krylov-BDDC solvers for nonlinear cardiac mechanics

    KAUST Repository

    Pavarino, L.F.

    2015-07-18

    The aim of this work is to design and study a Balancing Domain Decomposition by Constraints (BDDC) solver for the nonlinear elasticity system modeling the mechanical deformation of cardiac tissue. The contraction–relaxation process in the myocardium is induced by the generation and spread of the bioelectrical excitation throughout the tissue and it is mathematically described by the coupling of cardiac electro-mechanical models consisting of systems of partial and ordinary differential equations. In this study, the discretization of the electro-mechanical models is performed by Q1 finite elements in space and semi-implicit finite difference schemes in time, leading to the solution of a large-scale linear system for the bioelectrical potentials and a nonlinear system for the mechanical deformation at each time step of the simulation. The parallel mechanical solver proposed in this paper consists in solving the nonlinear system with a Newton-Krylov-BDDC method, based on the parallel solution of local mechanical problems and a coarse problem for the so-called primal unknowns. Three-dimensional parallel numerical tests on different machines show that the proposed parallel solver is scalable in the number of subdomains, quasi-optimal in the ratio of subdomain to mesh sizes, and robust with respect to tissue anisotropy.

  16. IGA-ADS: Isogeometric analysis FEM using ADS solver

    Science.gov (United States)

    Łoś, Marcin M.; Woźniak, Maciej; Paszyński, Maciej; Lenharth, Andrew; Hassaan, Muhamm Amber; Pingali, Keshav

    2017-08-01

    In this paper we present a fast explicit solver for solution of non-stationary problems using L2 projections with isogeometric finite element method. The solver has been implemented within GALOIS framework. It enables parallel multi-core simulations of different time-dependent problems, in 1D, 2D, or 3D. We have prepared the solver framework in a way that enables direct implementation of the selected PDE and corresponding boundary conditions. In this paper we describe the installation, implementation of exemplary three PDEs, and execution of the simulations on multi-core Linux cluster nodes. We consider three case studies, including heat transfer, linear elasticity, as well as non-linear flow in heterogeneous media. The presented package generates output suitable for interfacing with Gnuplot and ParaView visualization software. The exemplary simulations show near perfect scalability on Gilbert shared-memory node with four Intel® Xeon® CPU E7-4860 processors, each possessing 10 physical cores (for a total of 40 cores).

  17. A parallel direct solver for the self-adaptive hp Finite Element Method

    KAUST Repository

    Paszyński, Maciej R.

    2010-03-01

    In this paper we present a new parallel multi-frontal direct solver, dedicated for the hp Finite Element Method (hp-FEM). The self-adaptive hp-FEM generates in a fully automatic mode, a sequence of hp-meshes delivering exponential convergence of the error with respect to the number of degrees of freedom (d.o.f.) as well as the CPU time, by performing a sequence of hp refinements starting from an arbitrary initial mesh. The solver constructs an initial elimination tree for an arbitrary initial mesh, and expands the elimination tree each time the mesh is refined. This allows us to keep track of the order of elimination for the solver. The solver also minimizes the memory usage, by de-allocating partial LU factorizations computed during the elimination stage of the solver, and recomputes them for the backward substitution stage, by utilizing only about 10% of the computational time necessary for the original computations. The solver has been tested on 3D Direct Current (DC) borehole resistivity measurement simulations problems. We measure the execution time and memory usage of the solver over a large regular mesh with 1.5 million degrees of freedom as well as on the highly non-regular mesh, generated by the self-adaptive h p-FEM, with finite elements of various sizes and polynomial orders of approximation varying from p = 1 to p = 9. From the presented experiments it follows that the parallel solver scales well up to the maximum number of utilized processors. The limit for the solver scalability is the maximum sequential part of the algorithm: the computations of the partial LU factorizations over the longest path, coming from the root of the elimination tree down to the deepest leaf. © 2009 Elsevier Inc. All rights reserved.

  18. THE PROBLEM OF LEGAL REGULATION OF THE OPERATION OF THE OVER-THE-COUNTER (OTC) CURRENCY MARKET (FOREX) IN UKRAINE AND THE EU

    OpenAIRE

    Eugene Podorozhnyi; Dmytro Sirokha; Pavlo Komirchyi

    2017-01-01

    The aim of the article is to evaluate the state of legal institutionalization of the OTC foreign exchange market in Ukraine, as well as its comparison with the foreign experience of legal regulation of OTC currency relations in Ukraine and EU countries. The subject of the study is the legal and administrative framework for the functioning of the OTC currency market (Forex) in Ukraine and in the EU countries. The methodology of the study consists of: historical and legal method, which allowed ...

  19. Legal Hybrids

    DEFF Research Database (Denmark)

    Herrmann, Janne Rothmar

    2009-01-01

    in which embryos and foetuses are placed are much more complex. These categories are identified using Danish legislation as an example and on that basis the article extracts and identifies the different parameters that play a part in the legal categorisation of the human conceptus.......The article discusses the inadequacy of traditional theory on legal personhood in relation to embryos and foetuses. To challenge the somewhat binary view of legal personhood according to which the ‘born alive' criterion is paramount the article demonstrates that the number of legal categories...

  20. [Medical surveillance in university: organizational difficulties, legal problems, scientific e technical specificities. Experience of University of Milan Bicocca].

    Science.gov (United States)

    D'Orso, M I; Giuliani, C; Assini, R; Riva, M A; Cesana, G

    2012-01-01

    Our research describes activities of Occupational Health carried out during last year in University of Milan Bicocca by Occupational Doctors. We describe results of medical surveillance in 1153 employees or students exposed to occupational risks for health and safety. We report results obtained, technical difficulties, organizational problems, and preventive actions decided to improve functionality of our activity. Students seem to be less protected and consequently seem to have higher professional safety and health risks.

  1. Relations of Parenting Quality, Interparental Conflict, and Overnights with Mental Health Problems of Children in Divorcing Families with High Legal Conflict

    Science.gov (United States)

    Sandler, Irwin N.; Wheeler, Lorey A.; Braver, Sanford L.

    2013-01-01

    The current study examined the associations between child mental health problems and the quality of maternal and paternal parenting, and how these associations were moderated by three contextual factors, quality of parenting by the other parent, interparental conflict, and the number of overnights parents had with the child. Data for the current study come from a sample of divorcing families who are in high legal conflict over developing or maintaining a parenting plan following divorce. Analyses revealed that the associations between child mental health problems and positive maternal and paternal parenting were moderated by the quality of parenting provided by the other parent and by the number of overnights children spent with parents, but not by the level of interparental conflict. When both parenting by the other parent and number of overnights were considered in the same model, only number of overnights moderated the relations between parenting and child behavior problems. The results support the proposition that the well-being of children in high conflict divorcing families is better when they spend adequate time with at least one parent who provides high quality parenting. PMID:24098960

  2. A distributed-memory hierarchical solver for general sparse linear systems

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chao [Stanford Univ., CA (United States). Inst. for Computational and Mathematical Engineering; Pouransari, Hadi [Stanford Univ., CA (United States). Dept. of Mechanical Engineering; Rajamanickam, Sivasankaran [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Computing Research; Boman, Erik G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Center for Computing Research; Darve, Eric [Stanford Univ., CA (United States). Inst. for Computational and Mathematical Engineering and Dept. of Mechanical Engineering

    2017-12-20

    We present a parallel hierarchical solver for general sparse linear systems on distributed-memory machines. For large-scale problems, this fully algebraic algorithm is faster and more memory-efficient than sparse direct solvers because it exploits the low-rank structure of fill-in blocks. Depending on the accuracy of low-rank approximations, the hierarchical solver can be used either as a direct solver or as a preconditioner. The parallel algorithm is based on data decomposition and requires only local communication for updating boundary data on every processor. Moreover, the computation-to-communication ratio of the parallel algorithm is approximately the volume-to-surface-area ratio of the subdomain owned by every processor. We also provide various numerical results to demonstrate the versatility and scalability of the parallel algorithm.

  3. Nonlinear multigrid solvers exploiting AMGe coarse spaces with approximation properties

    DEFF Research Database (Denmark)

    Christensen, Max la Cour; Vassilevski, Panayot S.; Villa, Umberto

    2017-01-01

    discretizations on general unstructured grids for a large class of nonlinear partial differential equations, including saddle point problems. The approximation properties of the coarse spaces ensure that our FAS approach for general unstructured meshes leads to optimal mesh-independent convergence rates similar...... to those achieved by geometric FAS on a nested hierarchy of refined meshes. In the numerical results, Newton’s method and Picard iterations with state-of-the-art inner linear solvers are compared to our FAS algorithm for the solution of a nonlinear saddle point problem arising from porous media flow...

  4. NITSOL: A Newton iterative solver for nonlinear systems

    Energy Technology Data Exchange (ETDEWEB)

    Pernice, M. [Univ. of Utah, Salt Lake City, UT (United States); Walker, H.F. [Utah State Univ., Logan, UT (United States)

    1996-12-31

    Newton iterative methods, also known as truncated Newton methods, are implementations of Newton`s method in which the linear systems that characterize Newton steps are solved approximately using iterative linear algebra methods. Here, we outline a well-developed Newton iterative algorithm together with a Fortran implementation called NITSOL. The basic algorithm is an inexact Newton method globalized by backtracking, in which each initial trial step is determined by applying an iterative linear solver until an inexact Newton criterion is satisfied. In the implementation, the user can specify inexact Newton criteria in several ways and select an iterative linear solver from among several popular {open_quotes}transpose-free{close_quotes} Krylov subspace methods. Jacobian-vector products used by the Krylov solver can be either evaluated analytically with a user-supplied routine or approximated using finite differences of function values. A flexible interface permits a wide variety of preconditioning strategies and allows the user to define a preconditioner and optionally update it periodically. We give details of these and other features and demonstrate the performance of the implementation on a representative set of test problems.

  5. Matlab Geochemistry: An open source geochemistry solver based on MRST

    Science.gov (United States)

    McNeece, C. J.; Raynaud, X.; Nilsen, H.; Hesse, M. A.

    2017-12-01

    The study of geological systems often requires the solution of complex geochemical relations. To address this need we present an open source geochemical solver based on the Matlab Reservoir Simulation Toolbox (MRST) developed by SINTEF. The implementation supports non-isothermal multicomponent aqueous complexation, surface complexation, ion exchange, and dissolution/precipitation reactions. The suite of tools available in MRST allows for rapid model development, in particular the incorporation of geochemical calculations into transport simulations of multiple phases, complex domain geometry and geomechanics. Different numerical schemes and additional physics can be easily incorporated into the existing tools through the object-oriented framework employed by MRST. The solver leverages the automatic differentiation tools available in MRST to solve arbitrarily complex geochemical systems with any choice of species or element concentration as input. Four mathematical approaches enable the solver to be quite robust: 1) the choice of chemical elements as the basis components makes all entries in the composition matrix positive thus preserving convexity, 2) a log variable transformation is used which transfers the nonlinearity to the convex composition matrix, 3) a priori bounds on variables are calculated from the structure of the problem, constraining Netwon's path and 4) an initial guess is calculated implicitly by sequentially adding model complexity. As a benchmark we compare the model to experimental and semi-analytic solutions of the coupled salinity-acidity transport system. Together with the reservoir simulation capabilities of MRST the solver offers a promising tool for geochemical simulations in reservoir domains for applications in a diversity of fields from enhanced oil recovery to radionuclide storage.

  6. A robust multilevel simultaneous eigenvalue solver

    Science.gov (United States)

    Costiner, Sorin; Taasan, Shlomo

    1993-01-01

    Multilevel (ML) algorithms for eigenvalue problems are often faced with several types of difficulties such as: the mixing of approximated eigenvectors by the solution process, the approximation of incomplete clusters of eigenvectors, the poor representation of solution on coarse levels, and the existence of close or equal eigenvalues. Algorithms that do not treat appropriately these difficulties usually fail, or their performance degrades when facing them. These issues motivated the development of a robust adaptive ML algorithm which treats these difficulties, for the calculation of a few eigenvectors and their corresponding eigenvalues. The main techniques used in the new algorithm include: the adaptive completion and separation of the relevant clusters on different levels, the simultaneous treatment of solutions within each cluster, and the robustness tests which monitor the algorithm's efficiency and convergence. The eigenvectors' separation efficiency is based on a new ML projection technique generalizing the Rayleigh Ritz projection, combined with a technique, the backrotations. These separation techniques, when combined with an FMG formulation, in many cases lead to algorithms of O(qN) complexity, for q eigenvectors of size N on the finest level. Previously developed ML algorithms are less focused on the mentioned difficulties. Moreover, algorithms which employ fine level separation techniques are of O(q(sub 2)N) complexity and usually do not overcome all these difficulties. Computational examples are presented where Schrodinger type eigenvalue problems in 2-D and 3-D, having equal and closely clustered eigenvalues, are solved with the efficiency of the Poisson multigrid solver. A second order approximation is obtained in O(qN) work, where the total computational work is equivalent to only a few fine level relaxations per eigenvector.

  7. Accelerated Cyclic Reduction: A Distributed-Memory Fast Solver for Structured Linear Systems

    KAUST Repository

    Chávez, Gustavo

    2017-12-15

    We present Accelerated Cyclic Reduction (ACR), a distributed-memory fast solver for rank-compressible block tridiagonal linear systems arising from the discretization of elliptic operators, developed here for three dimensions. Algorithmic synergies between Cyclic Reduction and hierarchical matrix arithmetic operations result in a solver that has O(kNlogN(logN+k2)) arithmetic complexity and O(k Nlog N) memory footprint, where N is the number of degrees of freedom and k is the rank of a block in the hierarchical approximation, and which exhibits substantial concurrency. We provide a baseline for performance and applicability by comparing with the multifrontal method with and without hierarchical semi-separable matrices, with algebraic multigrid and with the classic cyclic reduction method. Over a set of large-scale elliptic systems with features of nonsymmetry and indefiniteness, the robustness of the direct solvers extends beyond that of the multigrid solver, and relative to the multifrontal approach ACR has lower or comparable execution time and size of the factors, with substantially lower numerical ranks. ACR exhibits good strong and weak scaling in a distributed context and, as with any direct solver, is advantageous for problems that require the solution of multiple right-hand sides. Numerical experiments show that the rank k patterns are of O(1) for the Poisson equation and of O(n) for the indefinite Helmholtz equation. The solver is ideal in situations where low-accuracy solutions are sufficient, or otherwise as a preconditioner within an iterative method.

  8. Accelerated Cyclic Reduction: A Distributed-Memory Fast Solver for Structured Linear Systems

    KAUST Repository

    Chá vez, Gustavo; Turkiyyah, George; Zampini, Stefano; Ltaief, Hatem; Keyes, David E.

    2017-01-01

    We present Accelerated Cyclic Reduction (ACR), a distributed-memory fast solver for rank-compressible block tridiagonal linear systems arising from the discretization of elliptic operators, developed here for three dimensions. Algorithmic synergies between Cyclic Reduction and hierarchical matrix arithmetic operations result in a solver that has O(kNlogN(logN+k2)) arithmetic complexity and O(k Nlog N) memory footprint, where N is the number of degrees of freedom and k is the rank of a block in the hierarchical approximation, and which exhibits substantial concurrency. We provide a baseline for performance and applicability by comparing with the multifrontal method with and without hierarchical semi-separable matrices, with algebraic multigrid and with the classic cyclic reduction method. Over a set of large-scale elliptic systems with features of nonsymmetry and indefiniteness, the robustness of the direct solvers extends beyond that of the multigrid solver, and relative to the multifrontal approach ACR has lower or comparable execution time and size of the factors, with substantially lower numerical ranks. ACR exhibits good strong and weak scaling in a distributed context and, as with any direct solver, is advantageous for problems that require the solution of multiple right-hand sides. Numerical experiments show that the rank k patterns are of O(1) for the Poisson equation and of O(n) for the indefinite Helmholtz equation. The solver is ideal in situations where low-accuracy solutions are sufficient, or otherwise as a preconditioner within an iterative method.

  9. Parallelization of the preconditioned IDR solver for modern multicore computer systems

    Science.gov (United States)

    Bessonov, O. A.; Fedoseyev, A. I.

    2012-10-01

    This paper present the analysis, parallelization and optimization approach for the large sparse matrix solver CNSPACK for modern multicore microprocessors. CNSPACK is an advanced solver successfully used for coupled solution of stiff problems arising in multiphysics applications such as CFD, semiconductor transport, kinetic and quantum problems. It employs iterative IDR algorithm with ILU preconditioning (user chosen ILU preconditioning order). CNSPACK has been successfully used during last decade for solving problems in several application areas, including fluid dynamics and semiconductor device simulation. However, there was a dramatic change in processor architectures and computer system organization in recent years. Due to this, performance criteria and methods have been revisited, together with involving the parallelization of the solver and preconditioner using Open MP environment. Results of the successful implementation for efficient parallelization are presented for the most advances computer system (Intel Core i7-9xx or two-processor Xeon 55xx/56xx).

  10. Legal terminology

    DEFF Research Database (Denmark)

    Engberg, Jan

    2013-01-01

    texts disseminating legal concepts in different situations (Wikipedia article for general public, article from ministry aimed at children and adolescents) and especially investigate, to what extent the paraphrase concept is applicable also for describing dissemination strategies in such situations...

  11. Domain decomposition solvers for nonlinear multiharmonic finite element equations

    KAUST Repository

    Copeland, D. M.

    2010-01-01

    In many practical applications, for instance, in computational electromagnetics, the excitation is time-harmonic. Switching from the time domain to the frequency domain allows us to replace the expensive time-integration procedure by the solution of a simple elliptic equation for the amplitude. This is true for linear problems, but not for nonlinear problems. However, due to the periodicity of the solution, we can expand the solution in a Fourier series. Truncating this Fourier series and approximating the Fourier coefficients by finite elements, we arrive at a large-scale coupled nonlinear system for determining the finite element approximation to the Fourier coefficients. The construction of fast solvers for such systems is very crucial for the efficiency of this multiharmonic approach. In this paper we look at nonlinear, time-harmonic potential problems as simple model problems. We construct and analyze almost optimal solvers for the Jacobi systems arising from the Newton linearization of the large-scale coupled nonlinear system that one has to solve instead of performing the expensive time-integration procedure. © 2010 de Gruyter.

  12. The tightness of control procedures in the legal protection provided by jurisdiction against directives issued by the Federal Government - a problem of competence distribution between the Federal Constitutional Court and the Federal Administrative Court?

    International Nuclear Information System (INIS)

    Zimmermann, B.

    1992-01-01

    The tightness of control procedures in the legal protection provided by jurisdiction against directives issued by the Federal Government - a problem of competence distribution between the Federal Constitutional Court and the Federal Administrative Court? The article examines questions of recourse to the competent court, problems concerning the admissibility of legal proceedings before the Federal Admininstrative Court, the competence of the Laender in performing administrative acts on behalf of the Federation, the effectiveness of legal protection and the relationship between the Laender and the Federation in terms of responsibility for constitutional rights. The legal protection offered by administrative law, against a directive of the Federal Government is wholly ineffective, as there is no legal position a Land could bring into play to defened itself against a directive leading to unlawful action. Inequites which thus occur can however be met via a dispute between the Federation and the Laender as provided by the constitution, as the content of a directive becomes relevant in attempts to exert influence on the competence issue. Ultimately the rulings of the Basic Law on competence serve to protect the citizen and the community against excesses. In this connection the constitutional rights in their capacity as negative competence rulings disqualify executive acts. (orig./HSCH) [de

  13. Problemática jurídica de los estados intersexuales. El caso colombiano Legal problematic of intersexual states. The Colombian case

    Directory of Open Access Journals (Sweden)

    Sandra Patricia Duque Quintero

    2010-08-01

    Full Text Available

    En este artículo de reflexión, basado en una investigación, se describe la problemática jurídica planteada por los estados intersexuales* en los menores de edad, y cómo la misma centra su discusión en la teoría del consentimiento informado, punto nodal en el que convergen, por un lado, la existencia de un sujeto titular de derechos, y por el otro, el modo en que debe darse la autorización para ciertos tratamientos médicos o quirúrgicos, así como para algunas intervenciones preventivas. Igualmente,

    se plantea la necesidad de articular el saber jurídico con el de otros campos como la medicina y la bioética, a fin de construir un marco teórico, analítico y práctico que aporte nuevas herramientas e instrumentos para resolver esta problemática. La Corte Constitucional Colombiana, como máximo órgano jurisdiccional, estableció algunos parámetros jurídicos para adoptar decisiones en estos casos pero cada uno de ellos plantea matices y opciones diferentes, y la solución que se pretenda adoptar debe ir dirigida a optimizar el bienestar del paciente.

     

    This is a reflection article based on research. In it, we describe the legal issues raised by intersexual states in minors. Individual rights and the way in which authorization should be given for certain medical and surgical treatments are analyzed in the perspective of the informed consent theory. We emphasize on the

  14. Domain decomposed preconditioners with Krylov subspace methods as subdomain solvers

    Energy Technology Data Exchange (ETDEWEB)

    Pernice, M. [Univ. of Utah, Salt Lake City, UT (United States)

    1994-12-31

    Domain decomposed preconditioners for nonsymmetric partial differential equations typically require the solution of problems on the subdomains. Most implementations employ exact solvers to obtain these solutions. Consequently work and storage requirements for the subdomain problems grow rapidly with the size of the subdomain problems. Subdomain solves constitute the single largest computational cost of a domain decomposed preconditioner, and improving the efficiency of this phase of the computation will have a significant impact on the performance of the overall method. The small local memory available on the nodes of most message-passing multicomputers motivates consideration of the use of an iterative method for solving subdomain problems. For large-scale systems of equations that are derived from three-dimensional problems, memory considerations alone may dictate the need for using iterative methods for the subdomain problems. In addition to reduced storage requirements, use of an iterative solver on the subdomains allows flexibility in specifying the accuracy of the subdomain solutions. Substantial savings in solution time is possible if the quality of the domain decomposed preconditioner is not degraded too much by relaxing the accuracy of the subdomain solutions. While some work in this direction has been conducted for symmetric problems, similar studies for nonsymmetric problems appear not to have been pursued. This work represents a first step in this direction, and explores the effectiveness of performing subdomain solves using several transpose-free Krylov subspace methods, GMRES, transpose-free QMR, CGS, and a smoothed version of CGS. Depending on the difficulty of the subdomain problem and the convergence tolerance used, a reduction in solution time is possible in addition to the reduced memory requirements. The domain decomposed preconditioner is a Schur complement method in which the interface operators are approximated using interface probing.

  15. A high-performance Riccati based solver for tree-structured quadratic programs

    DEFF Research Database (Denmark)

    Frison, Gianluca; Kouzoupis, Dimitris; Diehl, Moritz

    2017-01-01

    the online solution of such problems challenging and the development of tailored solvers crucial. In this paper, an interior point method is presented that can solve Quadratic Programs (QPs) arising in multi-stage MPC efficiently by means of a tree-structured Riccati recursion and a high-performance linear...... algebra library. A performance comparison with code-generated and general purpose sparse QP solvers shows that the computation times can be significantly reduced for all problem sizes that are practically relevant in embedded MPC applications. The presented implementation is freely available as part...

  16. The cost of continuity: A study of the performance of isogeometric finite elements using direct solvers

    KAUST Repository

    Collier, Nathan; Pardo, David; Dalcí n, Lisandro D.; Paszyński, Maciej R.; Calo, Victor M.

    2012-01-01

    We study the performance of direct solvers on linear systems of equations resulting from isogeometric analysis. The problem of choice is the canonical Laplace equation in three dimensions. From this study we conclude that for a fixed number of unknowns and polynomial degree of approximation, a higher degree of continuity k drastically increases the CPU time and RAM needed to solve the problem when using a direct solver. This paper presents numerical results detailing the phenomenon as well as a theoretical analysis that explains the underlying cause. © 2011 Elsevier B.V.

  17. The cost of continuity: A study of the performance of isogeometric finite elements using direct solvers

    KAUST Repository

    Collier, Nathan

    2012-03-01

    We study the performance of direct solvers on linear systems of equations resulting from isogeometric analysis. The problem of choice is the canonical Laplace equation in three dimensions. From this study we conclude that for a fixed number of unknowns and polynomial degree of approximation, a higher degree of continuity k drastically increases the CPU time and RAM needed to solve the problem when using a direct solver. This paper presents numerical results detailing the phenomenon as well as a theoretical analysis that explains the underlying cause. © 2011 Elsevier B.V.

  18. A Parallel Algebraic Multigrid Solver on Graphics Processing Units

    KAUST Repository

    Haase, Gundolf

    2010-01-01

    The paper presents a multi-GPU implementation of the preconditioned conjugate gradient algorithm with an algebraic multigrid preconditioner (PCG-AMG) for an elliptic model problem on a 3D unstructured grid. An efficient parallel sparse matrix-vector multiplication scheme underlying the PCG-AMG algorithm is presented for the many-core GPU architecture. A performance comparison of the parallel solver shows that a singe Nvidia Tesla C1060 GPU board delivers the performance of a sixteen node Infiniband cluster and a multi-GPU configuration with eight GPUs is about 100 times faster than a typical server CPU core. © 2010 Springer-Verlag.

  19. Modelo de selección de cartera con Solver

    Directory of Open Access Journals (Sweden)

    P. Fogués Zornoza

    2012-04-01

    Full Text Available In this paper, we present an example of linear optimization in the context of degrees in Economics or Business Administration and Management. We show techniques that enable students to go deep and investigate in real problems that have been modelled using the Excel platform. The model shown here has been developed by a student and it consists in minimizing the absolute deviations over the average expected return of a portfolio of securities, using the solver tool that it is included in this software.

  20. Legality in multiple legal orders

    NARCIS (Netherlands)

    Besselink, L.F.M.; Pennings, F.J.L.; Prechal, A.

    2010-01-01

    This is the Introductory chapter to The Eclipse of the Legality Principle in the European Union, Edited by Leonard Besselink, Frans Pennings, Sacha Prechal [European Monographs, vol. 75], Kluwer Law International, Alphen aan den Rijn, 2011 [2010], xxv + 303 pp.

  1. Using SPARK as a Solver for Modelica

    Energy Technology Data Exchange (ETDEWEB)

    Wetter, Michael; Wetter, Michael; Haves, Philip; Moshier, Michael A.; Sowell, Edward F.

    2008-06-30

    Modelica is an object-oriented acausal modeling language that is well positioned to become a de-facto standard for expressing models of complex physical systems. To simulate a model expressed in Modelica, it needs to be translated into executable code. For generating run-time efficient code, such a translation needs to employ algebraic formula manipulations. As the SPARK solver has been shown to be competitive for generating such code but currently cannot be used with the Modelica language, we report in this paper how SPARK's symbolic and numerical algorithms can be implemented in OpenModelica, an open-source implementation of a Modelica modeling and simulation environment. We also report benchmark results that show that for our air flow network simulation benchmark, the SPARK solver is competitive with Dymola, which is believed to provide the best solver for Modelica.

  2. New iterative solvers for the NAG Libraries

    Energy Technology Data Exchange (ETDEWEB)

    Salvini, S.; Shaw, G. [Numerical Algorithms Group Ltd., Oxford (United Kingdom)

    1996-12-31

    The purpose of this paper is to introduce the work which has been carried out at NAG Ltd to update the iterative solvers for sparse systems of linear equations, both symmetric and unsymmetric, in the NAG Fortran 77 Library. Our current plans to extend this work and include it in our other numerical libraries in our range are also briefly mentioned. We have added to the Library the new Chapter F11, entirely dedicated to sparse linear algebra. At Mark 17, the F11 Chapter includes sparse iterative solvers, preconditioners, utilities and black-box routines for sparse symmetric (both positive-definite and indefinite) linear systems. Mark 18 will add solvers, preconditioners, utilities and black-boxes for sparse unsymmetric systems: the development of these has already been completed.

  3. s-Step Krylov Subspace Methods as Bottom Solvers for Geometric Multigrid

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Samuel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lijewski, Mike [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Almgren, Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Straalen, Brian Van [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Carson, Erin [Univ. of California, Berkeley, CA (United States); Knight, Nicholas [Univ. of California, Berkeley, CA (United States); Demmel, James [Univ. of California, Berkeley, CA (United States)

    2014-08-14

    Geometric multigrid solvers within adaptive mesh refinement (AMR) applications often reach a point where further coarsening of the grid becomes impractical as individual sub domain sizes approach unity. At this point the most common solution is to use a bottom solver, such as BiCGStab, to reduce the residual by a fixed factor at the coarsest level. Each iteration of BiCGStab requires multiple global reductions (MPI collectives). As the number of BiCGStab iterations required for convergence grows with problem size, and the time for each collective operation increases with machine scale, bottom solves in large-scale applications can constitute a significant fraction of the overall multigrid solve time. In this paper, we implement, evaluate, and optimize a communication-avoiding s-step formulation of BiCGStab (CABiCGStab for short) as a high-performance, distributed-memory bottom solver for geometric multigrid solvers. This is the first time s-step Krylov subspace methods have been leveraged to improve multigrid bottom solver performance. We use a synthetic benchmark for detailed analysis and integrate the best implementation into BoxLib in order to evaluate the benefit of a s-step Krylov subspace method on the multigrid solves found in the applications LMC and Nyx on up to 32,768 cores on the Cray XE6 at NERSC. Overall, we see bottom solver improvements of up to 4.2x on synthetic problems and up to 2.7x in real applications. This results in as much as a 1.5x improvement in solver performance in real applications.

  4. Legal Problems of the Principal.

    Science.gov (United States)

    Stern, Ralph D.; And Others

    The three talks included here treat aspects of the law--tort liability, student records, and the age of majority--as they relate to the principal. Specifically, the talk on torts deals with the consequences of principal negligence in the event of injuries to students. Assurance is given that a reasonable and prudent principal will have a minimum…

  5. FUZZY LOGIC IN LEGAL EDUCATION

    Directory of Open Access Journals (Sweden)

    Z. Gonul BALKIR

    2011-04-01

    Full Text Available The necessity of examination of every case within its peculiar conditions in social sciences requires different approaches complying with the spirit and nature of social sciences. Multiple realities require different and various perceptual interpretations. In modern world and social sciences, interpretation of perception of valued and multi-valued have been started to be understood by the principles of fuzziness and fuzzy logic. Having the verbally expressible degrees of truthness such as true, very true, rather true, etc. fuzzy logic provides the opportunity for the interpretation of especially complex and rather vague set of information by flexibility or equivalence of the variables’ of fuzzy limitations. The methods and principles of fuzzy logic can be benefited in examination of the methodological problems of law, especially in the applications of filling the legal loopholes arising from the ambiguities and interpretation problems in order to understand the legal rules in a more comprehensible and applicable way and the efficiency of legal implications. On the other hand, fuzzy logic can be used as a technical legal method in legal education and especially in legal case studies and legal practice applications in order to provide the perception of law as a value and the more comprehensive and more quality perception and interpretation of value of justice, which is the core value of law. In the perception of what happened as it has happened in legal relationships and formations, the understanding of social reality and sociological legal rules with multi valued sense perspective and the their applications in accordance with the fuzzy logic’s methods could create more equivalent and just results. It can be useful for the young lawyers and law students as a facilitating legal method especially in the materialization of the perception and interpretation of multi valued and variables. Using methods and principles of fuzzy logic in legal

  6. Cafesat: A modern sat solver for scala

    OpenAIRE

    Blanc Régis

    2013-01-01

    We present CafeSat a SAT solver written in the Scala programming language. CafeSat is a modern solver based on DPLL and featuring many state of the art techniques and heuristics. It uses two watched literals for Boolean constraint propagation conict driven learning along with clause deletion a restarting strategy and the VSIDS heuristics for choosing the branching literal. CafeSat is both sound and complete. In order to achieve reasonable performance low level and hand tuned data structures a...

  7. THE PROBLEM OF LEGAL REGULATION OF THE OPERATION OF THE OVER-THE-COUNTER (OTC CURRENCY MARKET (FOREX IN UKRAINE AND THE EU

    Directory of Open Access Journals (Sweden)

    Eugene Podorozhnyi

    2017-12-01

    Full Text Available The aim of the article is to evaluate the state of legal institutionalization of the OTC foreign exchange market in Ukraine, as well as its comparison with the foreign experience of legal regulation of OTC currency relations in Ukraine and EU countries. The subject of the study is the legal and administrative framework for the functioning of the OTC currency market (Forex in Ukraine and in the EU countries. The methodology of the study consists of: historical and legal method, which allowed determining the preconditions for the emergence of OTC markets in Ukraine and the world and the principles of their functioning; system and structural method, which was used to analyse the world monetary system as an institutional and functional form of organization of international monetary and financial relations; a formal legal method that allowed us to comprehensively investigate a condition of regulation of the functioning of Forex in Ukraine, to identify its shortcomings, gaps, contradictions, and miscalculations, as well as to develop recommendations aimed at their elimination; a comparative and legal method that provided a deeper study of the specifics of the legal regulation of the functioning of Forex in the EU and to define ways of implementing a positive foreign experience in the national legal system. The results of the conducted legal study have shown that in Ukraine, the Forex market operates in legal vacuum conditions that negatively affect either the protection of the rights of forex clients or the amount of tax revenues to the state budget. The most acceptable way to eliminate this shortcoming is to implement the main principles and requirements of the MiFID in the national legislation. Practical impact. The research of experience of EU countries regarding the legal regulation of Forex companies activity and also regarding the creation of legal bases for implementation by the specified companies of self-regulation – it is a necessary

  8. Fast Multipole-Based Elliptic PDE Solver and Preconditioner

    KAUST Repository

    Ibeid, Huda

    2016-12-07

    Exascale systems are predicted to have approximately one billion cores, assuming Gigahertz cores. Limitations on affordable network topologies for distributed memory systems of such massive scale bring new challenges to the currently dominant parallel programing model. Currently, there are many efforts to evaluate the hardware and software bottlenecks of exascale designs. It is therefore of interest to model application performance and to understand what changes need to be made to ensure extrapolated scalability. Fast multipole methods (FMM) were originally developed for accelerating N-body problems for particle-based methods in astrophysics and molecular dynamics. FMM is more than an N-body solver, however. Recent efforts to view the FMM as an elliptic PDE solver have opened the possibility to use it as a preconditioner for even a broader range of applications. In this thesis, we (i) discuss the challenges for FMM on current parallel computers and future exascale architectures, with a focus on inter-node communication, and develop a performance model that considers the communication patterns of the FMM for spatially quasi-uniform distributions, (ii) employ this performance model to guide performance and scaling improvement of FMM for all-atom molecular dynamics simulations of uniformly distributed particles, and (iii) demonstrate that, beyond its traditional use as a solver in problems for which explicit free-space kernel representations are available, the FMM has applicability as a preconditioner in finite domain elliptic boundary value problems, by equipping it with boundary integral capability for satisfying conditions at finite boundaries and by wrapping it in a Krylov method for extensibility to more general operators. Compared with multilevel methods, FMM is capable of comparable algebraic convergence rates down to the truncation error of the discretized PDE, and it has superior multicore and distributed memory scalability properties on commodity

  9. An Extensive Evaluation of Portfolio Approaches for Constraint Satisfaction Problems

    Directory of Open Access Journals (Sweden)

    Roberto Amadini

    2016-06-01

    Full Text Available In the context of Constraint Programming, a portfolio approach exploits the complementary strengths of a portfolio of different constraint solvers. The goal is to predict and run the best solver(s of the portfolio for solving a new, unseen problem. In this work we reproduce, simulate, and evaluate the performance of different portfolio approaches on extensive benchmarks of Constraint Satisfaction Problems. Empirical results clearly show the benefits of portfolio solvers in terms of both solved instances and solving time.

  10. Responsive Legal Approach to Law of Human Trafficking in Indonesia

    Science.gov (United States)

    Farhana

    2018-01-01

    Formation and legal changes influenced by the social and political dynamics. Law understood as the rules are rigid and too much emphasis on the legal aspects of the legal system or emphasize aspects of the legitimacy of the rules themselves, without associated with social problems. A Responsive legal approach is an approach the legal establishment…

  11. MGLab3D: An interactive environment for iterative solvers for elliptic PDEs in two and three dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Bordner, J.; Saied, F. [Univ. of Illinois, Urbana, IL (United States)

    1996-12-31

    GLab3D is an enhancement of an interactive environment (MGLab) for experimenting with iterative solvers and multigrid algorithms. It is implemented in MATLAB. The new version has built-in 3D elliptic pde`s and several iterative methods and preconditioners that were not available in the original version. A sparse direct solver option has also been included. The multigrid solvers have also been extended to 3D. The discretization and pde domains are restricted to standard finite differences on the unit square/cube. The power of this software studies in the fact that no programming is needed to solve, for example, the convection-diffusion equation in 3D with TFQMR and a customized V-cycle preconditioner, for a variety of problem sizes and mesh Reynolds, numbers. In addition to the graphical user interface, some sample drivers are included to show how experiments can be composed using the underlying suite of problems and solvers.

  12. Fast Multipole-Based Preconditioner for Sparse Iterative Solvers

    KAUST Repository

    Ibeid, Huda; Yokota, Rio; Keyes, David E.

    2014-01-01

    Among optimal hierarchical algorithms for the computational solution of elliptic problems, the Fast Multipole Method (FMM) stands out for its adaptability to emerging architectures, having high arithmetic intensity, tunable accuracy, and relaxed global synchronization requirements. We demonstrate that, beyond its traditional use as a solver in problems for which explicit free-space kernel representations are available, the FMM has applicability as a preconditioner in finite domain elliptic boundary value problems, by equipping it with boundary integral capability for finite boundaries and by wrapping it in a Krylov method for extensibility to more general operators. Compared with multilevel methods, it is capable of comparable algebraic convergence rates down to the truncation error of the discretized PDE, and it has superior multicore and distributed memory scalability properties on commodity architecture supercomputers.

  13. Fast Multipole-Based Preconditioner for Sparse Iterative Solvers

    KAUST Repository

    Ibeid, Huda

    2014-05-04

    Among optimal hierarchical algorithms for the computational solution of elliptic problems, the Fast Multipole Method (FMM) stands out for its adaptability to emerging architectures, having high arithmetic intensity, tunable accuracy, and relaxed global synchronization requirements. We demonstrate that, beyond its traditional use as a solver in problems for which explicit free-space kernel representations are available, the FMM has applicability as a preconditioner in finite domain elliptic boundary value problems, by equipping it with boundary integral capability for finite boundaries and by wrapping it in a Krylov method for extensibility to more general operators. Compared with multilevel methods, it is capable of comparable algebraic convergence rates down to the truncation error of the discretized PDE, and it has superior multicore and distributed memory scalability properties on commodity architecture supercomputers.

  14. Reforming Copyright in the Context of Exercise of the Human Right to Free Expression on the Internet: An Actual Problems of the Modern International Legal Politics

    Directory of Open Access Journals (Sweden)

    Irina V. Shugurova

    2015-12-01

    Full Text Available The authors discuss major trends in the area of reforming of copyright in the light of full exercise of internationally recognized human right to expression regarding the digital environment, especially the Internet, and demonstrate the significant situation when intellectual property rights, mainly author’s exclusive rights, build a lot of troubles for the information human rights. The article also looks at the changes in the understanding the relation between copyright and the human right to freedom of expression and information on the Internet. Much attention is paid to new moments in the modern doctrine of intellectual property that is inspired by process of digitization of author’s rights. There is conducted the approach to addressing copyright as one of the digital human rights resulted from property rights and right of creators to protection of their moral and economic interests. However, authors of the article departure from postulate that copyright is the human rights to a certain degree only. Moreover, this article examines the international legal approach to seeking the balance between the human right to freedom of expression, opinion and information, on the one hand, and copyright, especially as regards the Internet, on the other hand. There has been argued that key role in elaborating and adopting the principled standards in this sphere belongs to international law, including international law of human rights. In addition, the latter, as authors have ascertained, must correspond to international law of intellectual property rights, international information law, and international competition law. The study focus on various aspects of solving the problem of adapting copyright to the digital environment.

  15. Application of alternating decision trees in selecting sparse linear solvers

    KAUST Repository

    Bhowmick, Sanjukta; Eijkhout, Victor; Freund, Yoav; Fuentes, Erika; Keyes, David E.

    2010-01-01

    The solution of sparse linear systems, a fundamental and resource-intensive task in scientific computing, can be approached through multiple algorithms. Using an algorithm well adapted to characteristics of the task can significantly enhance the performance, such as reducing the time required for the operation, without compromising the quality of the result. However, the best solution method can vary even across linear systems generated in course of the same PDE-based simulation, thereby making solver selection a very challenging problem. In this paper, we use a machine learning technique, Alternating Decision Trees (ADT), to select efficient solvers based on the properties of sparse linear systems and runtime-dependent features, such as the stages of simulation. We demonstrate the effectiveness of this method through empirical results over linear systems drawn from computational fluid dynamics and magnetohydrodynamics applications. The results also demonstrate that using ADT can resolve the problem of over-fitting, which occurs when limited amount of data is available. © 2010 Springer Science+Business Media LLC.

  16. Decision-Making and Problem-Solving Approaches in Pharmacy Education.

    Science.gov (United States)

    Martin, Lindsay C; Donohoe, Krista L; Holdford, David A

    2016-04-25

    Domain 3 of the Center for the Advancement of Pharmacy Education (CAPE) 2013 Educational Outcomes recommends that pharmacy school curricula prepare students to be better problem solvers, but are silent on the type of problems they should be prepared to solve. We identified five basic approaches to problem solving in the curriculum at a pharmacy school: clinical, ethical, managerial, economic, and legal. These approaches were compared to determine a generic process that could be applied to all pharmacy decisions. Although there were similarities in the approaches, generic problem solving processes may not work for all problems. Successful problem solving requires identification of the problems faced and application of the right approach to the situation. We also advocate that the CAPE Outcomes make explicit the importance of different approaches to problem solving. Future pharmacists will need multiple approaches to problem solving to adapt to the complexity of health care.

  17. Iterative linear solvers in a 2D radiation-hydrodynamics code: Methods and performance

    International Nuclear Information System (INIS)

    Baldwin, C.; Brown, P.N.; Falgout, R.; Graziani, F.; Jones, J.

    1999-01-01

    Computer codes containing both hydrodynamics and radiation play a central role in simulating both astrophysical and inertial confinement fusion (ICF) phenomena. A crucial aspect of these codes is that they require an implicit solution of the radiation diffusion equations. The authors present in this paper the results of a comparison of five different linear solvers on a range of complex radiation and radiation-hydrodynamics problems. The linear solvers used are diagonally scaled conjugate gradient, GMRES with incomplete LU preconditioning, conjugate gradient with incomplete Cholesky preconditioning, multigrid, and multigrid-preconditioned conjugate gradient. These problems involve shock propagation, opacities varying over 5--6 orders of magnitude, tabular equations of state, and dynamic ALE (Arbitrary Lagrangian Eulerian) meshes. They perform a problem size scalability study by comparing linear solver performance over a wide range of problem sizes from 1,000 to 100,000 zones. The fundamental question they address in this paper is: Is it more efficient to invert the matrix in many inexpensive steps (like diagonally scaled conjugate gradient) or in fewer expensive steps (like multigrid)? In addition, what is the answer to this question as a function of problem size and is the answer problem dependent? They find that the diagonally scaled conjugate gradient method performs poorly with the growth of problem size, increasing in both iteration count and overall CPU time with the size of the problem and also increasing for larger time steps. For all problems considered, the multigrid algorithms scale almost perfectly (i.e., the iteration count is approximately independent of problem size and problem time step). For pure radiation flow problems (i.e., no hydrodynamics), they see speedups in CPU time of factors of ∼15--30 for the largest problems, when comparing the multigrid solvers relative to diagonal scaled conjugate gradient

  18. UN legal advisers meet

    International Nuclear Information System (INIS)

    1969-01-01

    Legal Advisers from twelve international organizations belonging to the United Nations Organization's family met at the Agency's Headquarters in Vienna on 19 and 20 May to discuss legal problems of common administrative interest. The meeting was held on the initiative of the Agency while the UN Conference on the Law of Treaties was taking place in Vienna during April and May. With Mr. Constantin A. Stavropoulos, Under-Secretary, Legal Counsel of the United Nations, as chairman, this was the second meeting of Legal Advisers since 1954. The following organizations were represented: Food and Agriculture Organization of the United Nations, International Atomic Energy Agency, International Bank for Reconstruction and Development, International Civil Aviation Organization, International Labour Organisation, Inter-Governmental Maritime Consultative Organization, International Monetary Fund, International Telecommunication Union, United Nations, United Nations Educational, Scientific and Cultural Organization, United Nations Industrial Development Organization, World Health Organization. Topics discussed included the recruitment of legal staff and possible exchange of staff between organizations; competence and procedure of internal appeals committees, experience with cases before the Administrative Tribunals and evaluation of their judgments; experience with Staff Credit Unions; privileges and immunities of international organizations; headquarters and host government agreements; and patent policies of international organizations. Consultations will continue through correspondence and further meetings. (author)

  19. Extending the Finite Domain Solver of GNU Prolog

    NARCIS (Netherlands)

    Bloemen, Vincent; Diaz, Daniel; van der Bijl, Machiel; Abreu, Salvador; Ströder, Thomas; Swift, Terrance

    This paper describes three significant extensions for the Finite Domain solver of GNU Prolog. First, the solver now supports negative integers. Second, the solver detects and prevents integer overflows from occurring. Third, the internal representation of sparse domains has been redesigned to

  20. THE LEGAL PROBLEMS OF ESTABLISHING THE ADDITIONAL GUARANTEES OF REALIZATION OF CONSTITUTIONAL HUMAN AND CIVIL RIGHTS AND FREEDOMS BY THE CONSTITUENT ENTITIES OF THE RUSSIAN FEDERATION

    Directory of Open Access Journals (Sweden)

    Alexander Chuklin

    2017-01-01

    Full Text Available The subject. The article focuses on the need to improve legislative and law enforcement activities related to the consolidation of constituent entities of the Russian Federation additional guarantees of realization of constitutional human and civil rights and freedoms.The purpose of the article is to identify main ways of improvement the legal regulation additional guarantees of realization of constitutional human and civil rights and freedoms by the constituent entities of the Russian Federation.The methodology. The author uses a dialectical method, a method of analysis and synthesis, a formal legal method.The results and scope of application. The lack of unity in understanding the essence of additional guarantees of realization of rights and freedoms requires not only theoretical analysis of this legal category, but a consistent system of the legislation, and corresponding to the system of law enforcement practice. The legal establishment of the additional guarantees of realization of constitutional human and civil rights and freedoms, due solely to the will of the legislator of a constituent entitiy of the Russian Federation aimed at the concretization of constitutional rights and freedoms as well as of the security mechanisms (legal conditions, means of the implementation of these rights. Features of development of the corresponding constituent entitiy of the Russian Federation should be taken into account.One of the main directions of improvement of legal regulation in this field is legislative recognition of additional guarantees of realization of constitutional human and civil rights and freedoms established by the constituent entities of the Russian Federation. This concept should be reflected in the Federal law of October 6, 1999 No. 184-FZ "On General principles of organization of legislative (representative and executive bodies of state power of constituent entities of the Russian Federation", as well as in the constitutions (charters

  1. High-performance small-scale solvers for linear Model Predictive Control

    DEFF Research Database (Denmark)

    Frison, Gianluca; Sørensen, Hans Henrik Brandenborg; Dammann, Bernd

    2014-01-01

    , with the two main research areas of explicit MPC and tailored on-line MPC. State-of-the-art solvers in this second class can outperform optimized linear-algebra libraries (BLAS) only for very small problems, and do not explicitly exploit the hardware capabilities, relying on compilers for that. This approach...

  2. A parallel direct solver for the self-adaptive hp Finite Element Method

    KAUST Repository

    Paszyński, Maciej R.; Pardo, David; Torres-Verdí n, Carlos; Demkowicz, Leszek F.; Calo, Victor M.

    2010-01-01

    measurement simulations problems. We measure the execution time and memory usage of the solver over a large regular mesh with 1.5 million degrees of freedom as well as on the highly non-regular mesh, generated by the self-adaptive h p-FEM, with finite elements

  3. Balancing Energy and Performance in Dense Linear System Solvers for Hybrid ARM+GPU platforms

    Directory of Open Access Journals (Sweden)

    Juan P. Silva

    2016-04-01

    Full Text Available The high performance computing community has traditionally focused uniquely on the reduction of execution time, though in the last years, the optimization of energy consumption has become a main issue. A reduction of energy usage without a degradation of performance requires the adoption of energy-efficient hardware platforms accompanied by the development of energy-aware algorithms and computational kernels. The solution of linear systems is a key operation for many scientific and engineering problems. Its relevance has motivated an important amount of work, and consequently, it is possible to find high performance solvers for a wide variety of hardware platforms. In this work, we aim to develop a high performance and energy-efficient linear system solver. In particular, we develop two solvers for a low-power CPU-GPU platform, the NVIDIA Jetson TK1. These solvers implement the Gauss-Huard algorithm yielding an efficient usage of the target hardware as well as an efficient memory access. The experimental evaluation shows that the novel proposal reports important savings in both time and energy-consumption when compared with the state-of-the-art solvers of the platform.

  4. Integrating Eye Trackers with Handwriting Tablets to Discover Difficulties of Solving Geometry Problems

    Science.gov (United States)

    Lin, John J. H.; Lin, Sunny S. J.

    2018-01-01

    To deepen our understanding of those aspects of problems that cause the most difficulty for solvers, this study integrated eye-tracking with handwriting devices to investigate problem solvers' online processes while solving geometry problems. We are interested in whether the difference between successful and unsuccessful solvers can be identified…

  5. The Use of Sparse Direct Solver in Vector Finite Element Modeling for Calculating Two Dimensional (2-D) Magnetotelluric Responses in Transverse Electric (TE) Mode

    Science.gov (United States)

    Yihaa Roodhiyah, Lisa’; Tjong, Tiffany; Nurhasan; Sutarno, D.

    2018-04-01

    The late research, linear matrices of vector finite element in two dimensional(2-D) magnetotelluric (MT) responses modeling was solved by non-sparse direct solver in TE mode. Nevertheless, there is some weakness which have to be improved especially accuracy in the low frequency (10-3 Hz-10-5 Hz) which is not achieved yet and high cost computation in dense mesh. In this work, the solver which is used is sparse direct solver instead of non-sparse direct solverto overcome the weaknesses of solving linear matrices of vector finite element metod using non-sparse direct solver. Sparse direct solver will be advantageous in solving linear matrices of vector finite element method because of the matrix properties which is symmetrical and sparse. The validation of sparse direct solver in solving linear matrices of vector finite element has been done for a homogen half-space model and vertical contact model by analytical solution. Thevalidation result of sparse direct solver in solving linear matrices of vector finite element shows that sparse direct solver is more stable than non-sparse direct solver in computing linear problem of vector finite element method especially in low frequency. In the end, the accuracy of 2D MT responses modelling in low frequency (10-3 Hz-10-5 Hz) has been reached out under the efficient allocation memory of array and less computational time consuming.

  6. A Direct Elliptic Solver Based on Hierarchically Low-Rank Schur Complements

    KAUST Repository

    Chávez, Gustavo

    2017-03-17

    A parallel fast direct solver for rank-compressible block tridiagonal linear systems is presented. Algorithmic synergies between Cyclic Reduction and Hierarchical matrix arithmetic operations result in a solver with O(Nlog2N) arithmetic complexity and O(NlogN) memory footprint. We provide a baseline for performance and applicability by comparing with well-known implementations of the $$\\\\mathcal{H}$$ -LU factorization and algebraic multigrid within a shared-memory parallel environment that leverages the concurrency features of the method. Numerical experiments reveal that this method is comparable with other fast direct solvers based on Hierarchical Matrices such as $$\\\\mathcal{H}$$ -LU and that it can tackle problems where algebraic multigrid fails to converge.

  7. Wavelet-Based Poisson Solver for Use in Particle-in-Cell Simulations

    CERN Document Server

    Terzic, Balsa; Mihalcea, Daniel; Pogorelov, Ilya V

    2005-01-01

    We report on a successful implementation of a wavelet-based Poisson solver for use in 3D particle-in-cell simulations. One new aspect of our algorithm is its ability to treat the general (inhomogeneous) Dirichlet boundary conditions. The solver harnesses advantages afforded by the wavelet formulation, such as sparsity of operators and data sets, existence of effective preconditioners, and the ability simultaneously to remove numerical noise and further compress relevant data sets. Having tested our method as a stand-alone solver on two model problems, we merged it into IMPACT-T to obtain a fully functional serial PIC code. We present and discuss preliminary results of application of the new code to the modelling of the Fermilab/NICADD and AES/JLab photoinjectors.

  8. Wavelet-based Poisson Solver for use in Particle-In-Cell Simulations

    International Nuclear Information System (INIS)

    Terzic, B.; Mihalcea, D.; Bohn, C.L.; Pogorelov, I.V.

    2005-01-01

    We report on a successful implementation of a wavelet based Poisson solver for use in 3D particle-in-cell (PIC) simulations. One new aspect of our algorithm is its ability to treat the general(inhomogeneous) Dirichlet boundary conditions (BCs). The solver harnesses advantages afforded by the wavelet formulation, such as sparsity of operators and data sets, existence of effective preconditioners, and the ability simultaneously to remove numerical noise and further compress relevant data sets. Having tested our method as a stand-alone solver on two model problems, we merged it into IMPACT-T to obtain a fully functional serial PIC code. We present and discuss preliminary results of application of the new code to the modeling of the Fermilab/NICADD and AES/JLab photoinjectors

  9. Algorithms for parallel flow solvers on message passing architectures

    Science.gov (United States)

    Vanderwijngaart, Rob F.

    1995-01-01

    The purpose of this project has been to identify and test suitable technologies for implementation of fluid flow solvers -- possibly coupled with structures and heat equation solvers -- on MIMD parallel computers. In the course of this investigation much attention has been paid to efficient domain decomposition strategies for ADI-type algorithms. Multi-partitioning derives its efficiency from the assignment of several blocks of grid points to each processor in the parallel computer. A coarse-grain parallelism is obtained, and a near-perfect load balance results. In uni-partitioning every processor receives responsibility for exactly one block of grid points instead of several. This necessitates fine-grain pipelined program execution in order to obtain a reasonable load balance. Although fine-grain parallelism is less desirable on many systems, especially high-latency networks of workstations, uni-partition methods are still in wide use in production codes for flow problems. Consequently, it remains important to achieve good efficiency with this technique that has essentially been superseded by multi-partitioning for parallel ADI-type algorithms. Another reason for the concentration on improving the performance of pipeline methods is their applicability in other types of flow solver kernels with stronger implied data dependence. Analytical expressions can be derived for the size of the dynamic load imbalance incurred in traditional pipelines. From these it can be determined what is the optimal first-processor retardation that leads to the shortest total completion time for the pipeline process. Theoretical predictions of pipeline performance with and without optimization match experimental observations on the iPSC/860 very well. Analysis of pipeline performance also highlights the effect of uncareful grid partitioning in flow solvers that employ pipeline algorithms. If grid blocks at boundaries are not at least as large in the wall-normal direction as those

  10. Diffusion of Zonal Variables Using Node-Centered Diffusion Solver

    Energy Technology Data Exchange (ETDEWEB)

    Yang, T B

    2007-08-06

    Tom Kaiser [1] has done some preliminary work to use the node-centered diffusion solver (originally developed by T. Palmer [2]) in Kull for diffusion of zonal variables such as electron temperature. To avoid numerical diffusion, Tom used a scheme developed by Shestakov et al. [3] and found their scheme could, in the vicinity of steep gradients, decouple nearest-neighbor zonal sub-meshes leading to 'alternating-zone' (red-black mode) errors. Tom extended their scheme to couple the sub-meshes with appropriate chosen artificial diffusion and thereby solved the 'alternating-zone' problem. Because the choice of the artificial diffusion coefficient could be very delicate, it is desirable to use a scheme that does not require the artificial diffusion but still able to avoid both numerical diffusion and the 'alternating-zone' problem. In this document we present such a scheme.

  11. The Human Mind As General Problem Solver, Is Observed To Find ``Best'' Solutions, That Correspond To Highest Mental Coherence: Will Discuss ``sing Glass Type Theory'' of Princeton Physicist J J Hopfield, Points To How Best Use Our Own Human Mind!!

    Science.gov (United States)

    Gurr, Henry

    2014-03-01

    Princeton Physicist J. J. Hopfield's Mathematical Model of the Mammalian Brain, (Similar To Ising Glass Model of a crystal of magnetic spin particles) says our Brain-Work for Memory, Perception, Language, Thinking, etc, (Even the AHA-EUREKA-Flash Of Insight Type Problem Solving), is achieved by our massively inter-connected CNS Neurons ... working together ... MINIMIZING an analog of physical energy ... thus yielding Optimal Solutions: These ``best'' answers, correspond to highest mental coherence, for most facets organism response, beit mental (eg: perception, memory, ideas, thinking, etc) or physical-muscular-actions (eg speaking, tool using, trail following, etc). Our brain is this way, because living creature, MUST be evolved, so they will find & use the best actions, for survival!!! Our human heritage, is to instantly compute near optimal future plans, (mental & physical-muscular), and be able to accomplish plans reliably & efficiently. If you know of book or articles in these topic areas, please email to HenryG--USCA.edu How to work well, with your own ``self'', called mind-body, will follow!! Conjectures: Who is the ``I'' that appears to make decisions? Am ``I'' the master of my domain? Is there an ``I'' or am ``I'' merely an illusion of reality.

  12. Legal highs - legal aspects and legislative solutions.

    Science.gov (United States)

    Kapka-Skrzypczak, Lucyna; Kulpa, Piotr; Sawicki, Krzysztof; Cyranka, Małgorzata; Wojtyła, Andrzej; Kruszewski, Marcin

    2011-01-01

    In recent years the attention of society, the media and politicians has focused on the negative phenomenon of the occurrence of an enormous amount of new psychoactive substances flooding the European market. In Poland and in Europe they are known under the name 'legal highs' or 'smart drugs'. In many countries these compounds present a serious social and health problem. The core of the problem is the fact that in the light of the law these substances are legal, while actually they imitate the eff ect of illegal narcotics. Smart drugs are sold allegedly as 'products not intended for human consumption', under the cover of 'collector's commodities', 'incense sticks' or 'bath salts'. Efforts undertaken by many countries, including Poland, are biased towards gaining control over this pathological phenomenon by placing the subsequent substances on the list of prohibited agents. However, the resilient chemical and pharmaceutical industry still remains one step ahead by introducing new derivatives of already banned products, practically identical in action. The presented article is an attempt to bring closer the problem of smart drugs in Poland, from the occurrence of this alarming phenomenon, through the spread of sales in shops all over Poland, to a series of changes in the Polish anti-narcotic law, drastic actions of closing the shops throughout the entire country, and transferring the sale of smart drugs to the internet.

  13. Riemann solvers and undercompressive shocks of convex FPU chains

    International Nuclear Information System (INIS)

    Herrmann, Michael; Rademacher, Jens D M

    2010-01-01

    We consider FPU-type atomic chains with general convex potentials. The naive continuum limit in the hyperbolic space–time scaling is the p-system of mass and momentum conservation. We systematically compare Riemann solutions to the p-system with numerical solutions to discrete Riemann problems in FPU chains, and argue that the latter can be described by modified p-system Riemann solvers. We allow the flux to have a turning point, and observe a third type of elementary wave (conservative shocks) in the atomistic simulations. These waves are heteroclinic travelling waves and correspond to non-classical, undercompressive shocks of the p-system. We analyse such shocks for fluxes with one or more turning points. Depending on the convexity properties of the flux we propose FPU-Riemann solvers. Our numerical simulations confirm that Lax shocks are replaced by so-called dispersive shocks. For convex–concave flux we provide numerical evidence that convex FPU chains follow the p-system in generating conservative shocks that are supersonic. For concave–convex flux, however, the conservative shocks of the p-system are subsonic and do not appear in FPU-Riemann solutions

  14. Computational cost estimates for parallel shared memory isogeometric multi-frontal solvers

    KAUST Repository

    Woźniak, Maciej

    2014-06-01

    In this paper we present computational cost estimates for parallel shared memory isogeometric multi-frontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as O( p2log(N/p)) for one dimensional problems, O(Np2) for two dimensional problems, and O(N4/3p2) for three dimensional problems, where N is the number of degrees of freedom, and p is the polynomial order of approximation. The computational costs of the shared memory parallel isogeometric direct solver are compared with those corresponding to the sequential isogeometric direct solver, being the latest equal to O(N p2) for the one dimensional case, O(N1.5p3) for the two dimensional case, and O(N2p3) for the three dimensional case. The shared memory version significantly reduces both the scalability in terms of N and p. Theoretical estimates are compared with numerical experiments performed with linear, quadratic, cubic, quartic, and quintic B-splines, in one and two spatial dimensions. © 2014 Elsevier Ltd. All rights reserved.

  15. A generalized Poisson and Poisson-Boltzmann solver for electrostatic environments

    International Nuclear Information System (INIS)

    Fisicaro, G.; Goedecker, S.; Genovese, L.; Andreussi, O.; Marzari, N.

    2016-01-01

    The computational study of chemical reactions in complex, wet environments is critical for applications in many fields. It is often essential to study chemical reactions in the presence of applied electrochemical potentials, taking into account the non-trivial electrostatic screening coming from the solvent and the electrolytes. As a consequence, the electrostatic potential has to be found by solving the generalized Poisson and the Poisson-Boltzmann equations for neutral and ionic solutions, respectively. In the present work, solvers for both problems have been developed. A preconditioned conjugate gradient method has been implemented for the solution of the generalized Poisson equation and the linear regime of the Poisson-Boltzmann, allowing to solve iteratively the minimization problem with some ten iterations of the ordinary Poisson equation solver. In addition, a self-consistent procedure enables us to solve the non-linear Poisson-Boltzmann problem. Both solvers exhibit very high accuracy and parallel efficiency and allow for the treatment of periodic, free, and slab boundary conditions. The solver has been integrated into the BigDFT and Quantum-ESPRESSO electronic-structure packages and will be released as an independent program, suitable for integration in other codes

  16. A generalized Poisson and Poisson-Boltzmann solver for electrostatic environments.

    Science.gov (United States)

    Fisicaro, G; Genovese, L; Andreussi, O; Marzari, N; Goedecker, S

    2016-01-07

    The computational study of chemical reactions in complex, wet environments is critical for applications in many fields. It is often essential to study chemical reactions in the presence of applied electrochemical potentials, taking into account the non-trivial electrostatic screening coming from the solvent and the electrolytes. As a consequence, the electrostatic potential has to be found by solving the generalized Poisson and the Poisson-Boltzmann equations for neutral and ionic solutions, respectively. In the present work, solvers for both problems have been developed. A preconditioned conjugate gradient method has been implemented for the solution of the generalized Poisson equation and the linear regime of the Poisson-Boltzmann, allowing to solve iteratively the minimization problem with some ten iterations of the ordinary Poisson equation solver. In addition, a self-consistent procedure enables us to solve the non-linear Poisson-Boltzmann problem. Both solvers exhibit very high accuracy and parallel efficiency and allow for the treatment of periodic, free, and slab boundary conditions. The solver has been integrated into the BigDFT and Quantum-ESPRESSO electronic-structure packages and will be released as an independent program, suitable for integration in other codes.

  17. Computational cost estimates for parallel shared memory isogeometric multi-frontal solvers

    KAUST Repository

    Woźniak, Maciej; Kuźnik, Krzysztof M.; Paszyński, Maciej R.; Calo, Victor M.; Pardo, D.

    2014-01-01

    In this paper we present computational cost estimates for parallel shared memory isogeometric multi-frontal solvers. The estimates show that the ideal isogeometric shared memory parallel direct solver scales as O( p2log(N/p)) for one dimensional problems, O(Np2) for two dimensional problems, and O(N4/3p2) for three dimensional problems, where N is the number of degrees of freedom, and p is the polynomial order of approximation. The computational costs of the shared memory parallel isogeometric direct solver are compared with those corresponding to the sequential isogeometric direct solver, being the latest equal to O(N p2) for the one dimensional case, O(N1.5p3) for the two dimensional case, and O(N2p3) for the three dimensional case. The shared memory version significantly reduces both the scalability in terms of N and p. Theoretical estimates are compared with numerical experiments performed with linear, quadratic, cubic, quartic, and quintic B-splines, in one and two spatial dimensions. © 2014 Elsevier Ltd. All rights reserved.

  18. A generalized Poisson and Poisson-Boltzmann solver for electrostatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Fisicaro, G., E-mail: giuseppe.fisicaro@unibas.ch; Goedecker, S. [Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel (Switzerland); Genovese, L. [University of Grenoble Alpes, CEA, INAC-SP2M, L-Sim, F-38000 Grenoble (France); Andreussi, O. [Institute of Computational Science, Università della Svizzera Italiana, Via Giuseppe Buffi 13, CH-6904 Lugano (Switzerland); Theory and Simulations of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, Station 12, CH-1015 Lausanne (Switzerland); Marzari, N. [Theory and Simulations of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, Station 12, CH-1015 Lausanne (Switzerland)

    2016-01-07

    The computational study of chemical reactions in complex, wet environments is critical for applications in many fields. It is often essential to study chemical reactions in the presence of applied electrochemical potentials, taking into account the non-trivial electrostatic screening coming from the solvent and the electrolytes. As a consequence, the electrostatic potential has to be found by solving the generalized Poisson and the Poisson-Boltzmann equations for neutral and ionic solutions, respectively. In the present work, solvers for both problems have been developed. A preconditioned conjugate gradient method has been implemented for the solution of the generalized Poisson equation and the linear regime of the Poisson-Boltzmann, allowing to solve iteratively the minimization problem with some ten iterations of the ordinary Poisson equation solver. In addition, a self-consistent procedure enables us to solve the non-linear Poisson-Boltzmann problem. Both solvers exhibit very high accuracy and parallel efficiency and allow for the treatment of periodic, free, and slab boundary conditions. The solver has been integrated into the BigDFT and Quantum-ESPRESSO electronic-structure packages and will be released as an independent program, suitable for integration in other codes.

  19. Problems arising in connection with the commissioning of experts in conflict-oriented implementation of nuclear law. The legal status of expert opinions in administrative procedures under the Atomic Energy Act

    International Nuclear Information System (INIS)

    Fiebig, T.H.

    1995-01-01

    Court decisions available so far do not primarily consider the problems linked to the commissioning of an expert and his mandate, as well as the legal status of the commissioning of an expert as an administrative act which might be legally contestable. Thus there are at present no court decisions that would create legal certainty in matters of the act of commissioning a nuclear expert opinion. The current legal situation is such that an independent order for commissioning of an expert opinion in compliance with section 19 III AtG (Atomic Energy Act), which in general is given in response to the refusal of the facility operator to do so, can be independently contested on the basis of section 44 a, sentence 2 VwGO (Rules of Administrative Courts). The current practice of conflict-oriented, or nuclear power phase-out-oriented, implementation of the nuclear law poses a threat to our constitutional state and to our democracy. The supply of energy as a common good is of essential importance and thus deserves fair and objective treatment free of emotions, including the matter of nuclear energy. In cases of nuclear licensing procedures meeting with impedimental treatment by a Land government favouring the nuclear power phase-out, this treatment however not fitting into the Land governments' overall political line, there is reason to call upon the Federal Government to take action for clarifying the situation. (orig./HP) [de

  20. Asynchronous Parallelization of a CFD Solver

    OpenAIRE

    Abdi, Daniel S.; Bitsuamlak, Girma T.

    2015-01-01

    The article of record as published may be found at http://dx.doi.org/10.1155/2015/295393 A Navier-Stokes equations solver is parallelized to run on a cluster of computers using the domain decomposition method. Two approaches of communication and computation are investigated, namely, synchronous and asynchronous methods. Asynchronous communication between subdomains is not commonly used inCFDcodes; however, it has a potential to alleviate scaling bottlenecks incurred due to process...

  1. Chemical Mechanism Solvers in Air Quality Models

    Directory of Open Access Journals (Sweden)

    John C. Linford

    2011-09-01

    Full Text Available The solution of chemical kinetics is one of the most computationally intensivetasks in atmospheric chemical transport simulations. Due to the stiff nature of the system,implicit time stepping algorithms which repeatedly solve linear systems of equations arenecessary. This paper reviews the issues and challenges associated with the construction ofefficient chemical solvers, discusses several families of algorithms, presents strategies forincreasing computational efficiency, and gives insight into implementing chemical solverson accelerated computer architectures.

  2. Nuclear energy as a 'golden bridge'? Constitutional legal problems of the negotiation of the prolongation of the running time against skimming of profits; Kernenergie als 'goldene Bruecke'? Verfassungsrechtliche Probleme der Aushandlung von Laufzeitverlaengerungen gegen Gewinnabschoepfungen

    Energy Technology Data Exchange (ETDEWEB)

    Waldhoff, Christian; Aswege, Hanka von [Bonn Univ. (Germany). Lehrstuhl fuer Oeffentliches Recht

    2010-07-15

    The coalition agreement of Christian Demographic Union (CDU), Christian Social Union (CSU) and Free Democratic Party (FDP) from 26th October, 2009 characterizes the nuclear energy as a bridge technology. The coalition parties explain to prolong the running times of German nuclear power stations up to a reliable replacement by renewable energies. The conditions for the prolongation of the running times are to be regulated in agreement with energy supply companies. In the contribution under consideration, the authors report on the fiscal legal problems of the skimming of profits. Constitutional legal problems of the earmaking of a skimming of profits as well as a consensual agreement are discussed in this contribution. In the result, a financial constitutionally reliable way for the skimming of added profits due to prolongation of the running time is not evident. The legal earmaking of the duty advent for the promotion of renewable energies increases the constitutional doubts.

  3. Abusive Legalism

    OpenAIRE

    Cheung, Alvin

    2018-01-01

    This paper suggests that one response to growing scrutiny of authoritarian tactics is to turn to sub-constitutional public law, or private law. By using “ordinary” law in ways that seem consistent with formal and procedural aspects of rule of law, autocrats can nonetheless frustrate the rule of law and consolidate power, while also avoiding drawing unfavourable attention to that consolidation. I refer to this phenomenon as “abusive legalism.” This paper makes three main contributions to the s...

  4. High accuracy electromagnetic field solvers for cylindrical waveguides and axisymmetric structures using the finite element method

    International Nuclear Information System (INIS)

    Nelson, E.M.

    1993-12-01

    Some two-dimensional finite element electromagnetic field solvers are described and tested. For TE and TM modes in homogeneous cylindrical waveguides and monopole modes in homogeneous axisymmetric structures, the solvers find approximate solutions to a weak formulation of the wave equation. Second-order isoparametric lagrangian triangular elements represent the field. For multipole modes in axisymmetric structures, the solver finds approximate solutions to a weak form of the curl-curl formulation of Maxwell's equations. Second-order triangular edge elements represent the radial (ρ) and axial (z) components of the field, while a second-order lagrangian basis represents the azimuthal (φ) component of the field weighted by the radius ρ. A reduced set of basis functions is employed for elements touching the axis. With this basis the spurious modes of the curl-curl formulation have zero frequency, so spurious modes are easily distinguished from non-static physical modes. Tests on an annular ring, a pillbox and a sphere indicate the solutions converge rapidly as the mesh is refined. Computed eigenvalues with relative errors of less than a few parts per million are obtained. Boundary conditions for symmetric, periodic and symmetric-periodic structures are discussed and included in the field solver. Boundary conditions for structures with inversion symmetry are also discussed. Special corner elements are described and employed to improve the accuracy of cylindrical waveguide and monopole modes with singular fields at sharp corners. The field solver is applied to three problems: (1) cross-field amplifier slow-wave circuits, (2) a detuned disk-loaded waveguide linear accelerator structure and (3) a 90 degrees overmoded waveguide bend. The detuned accelerator structure is a critical application of this high accuracy field solver. To maintain low long-range wakefields, tight design and manufacturing tolerances are required

  5. A wavelet-based PWTD algorithm-accelerated time domain surface integral equation solver

    KAUST Repository

    Liu, Yang

    2015-10-26

    © 2015 IEEE. The multilevel plane-wave time-domain (PWTD) algorithm allows for fast and accurate analysis of transient scattering from, and radiation by, electrically large and complex structures. When used in tandem with marching-on-in-time (MOT)-based surface integral equation (SIE) solvers, it reduces the computational and memory costs of transient analysis from equation and equation to equation and equation, respectively, where Nt and Ns denote the number of temporal and spatial unknowns (Ergin et al., IEEE Trans. Antennas Mag., 41, 39-52, 1999). In the past, PWTD-accelerated MOT-SIE solvers have been applied to transient problems involving half million spatial unknowns (Shanker et al., IEEE Trans. Antennas Propag., 51, 628-641, 2003). Recently, a scalable parallel PWTD-accelerated MOT-SIE solver that leverages a hiearchical parallelization strategy has been developed and successfully applied to the transient problems involving ten million spatial unknowns (Liu et. al., in URSI Digest, 2013). We further enhanced the capabilities of this solver by implementing a compression scheme based on local cosine wavelet bases (LCBs) that exploits the sparsity in the temporal dimension (Liu et. al., in URSI Digest, 2014). Specifically, the LCB compression scheme was used to reduce the memory requirement of the PWTD ray data and computational cost of operations in the PWTD translation stage.

  6. Performance of uncertainty quantification methodologies and linear solvers in cardiovascular simulations

    Science.gov (United States)

    Seo, Jongmin; Schiavazzi, Daniele; Marsden, Alison

    2017-11-01

    Cardiovascular simulations are increasingly used in clinical decision making, surgical planning, and disease diagnostics. Patient-specific modeling and simulation typically proceeds through a pipeline from anatomic model construction using medical image data to blood flow simulation and analysis. To provide confidence intervals on simulation predictions, we use an uncertainty quantification (UQ) framework to analyze the effects of numerous uncertainties that stem from clinical data acquisition, modeling, material properties, and boundary condition selection. However, UQ poses a computational challenge requiring multiple evaluations of the Navier-Stokes equations in complex 3-D models. To achieve efficiency in UQ problems with many function evaluations, we implement and compare a range of iterative linear solver and preconditioning techniques in our flow solver. We then discuss applications to patient-specific cardiovascular simulation and how the problem/boundary condition formulation in the solver affects the selection of the most efficient linear solver. Finally, we discuss performance improvements in the context of uncertainty propagation. Support from National Institute of Health (R01 EB018302) is greatly appreciated.

  7. Improving mathematical problem solving : A computerized approach

    NARCIS (Netherlands)

    Harskamp, EG; Suhre, CJM

    Mathematics teachers often experience difficulties in teaching students to become skilled problem solvers. This paper evaluates the effectiveness of two interactive computer programs for high school mathematics problem solving. Both programs present students with problems accompanied by instruction

  8. Legal regulation of home births

    Directory of Open Access Journals (Sweden)

    Baturan Luka O.

    2015-01-01

    Full Text Available In this paper, authors tried to find efficient legal frame for home births. The main problem is the risk of life and health of a mother and a baby. If a mother wants a home labor, there are no legal obstacles ^for her to take the risk of her own life, after consultation with health-care professionals. However, society is obligated to protect unborn child from irrational behavior of the mother, if she acts against child's best interests. Legal rules were analyzed by methods of neo-institutional economic theory, while the risks of life and health of a mother and a baby were analyzed by medical science methods.

  9. The Legal Regulation of Cybersecurity

    OpenAIRE

    Darius Štitilis

    2013-01-01

    Cybercrime has become a global phenomenon, which is causing more harm to individual citizens, organizations, society and the state. Most countries in the world compare cybercrime with offences such as terrorism and drug trafficking due to its risks and profitability. Cybersecurity is the central category to fight cybercrime in cyberspace. Therefore, the strategic legal regulation of cybersecurity is one of the most relevant problems in EU, including Lithuania. So far cybersecurity legal regul...

  10. POSSOL, 2-D Poisson Equation Solver for Nonuniform Grid

    International Nuclear Information System (INIS)

    Orvis, W.J.

    1988-01-01

    1 - Description of program or function: POSSOL is a two-dimensional Poisson equation solver for problems with arbitrary non-uniform gridding in Cartesian coordinates. It is an adaptation of the uniform grid PWSCRT routine developed by Schwarztrauber and Sweet at the National Center for Atmospheric Research (NCAR). 2 - Method of solution: POSSOL will solve the Helmholtz equation on an arbitrary, non-uniform grid on a rectangular domain allowing only one type of boundary condition on any one side. It can also be used to handle more than one type of boundary condition on a side by means of a capacitance matrix technique. There are three types of boundary conditions that can be applied: fixed, derivative, or periodic

  11. Domain Decomposition Solvers for Frequency-Domain Finite Element Equations

    KAUST Repository

    Copeland, Dylan; Kolmbauer, Michael; Langer, Ulrich

    2010-01-01

    The paper is devoted to fast iterative solvers for frequency-domain finite element equations approximating linear and nonlinear parabolic initial boundary value problems with time-harmonic excitations. Switching from the time domain to the frequency domain allows us to replace the expensive time-integration procedure by the solution of a simple linear elliptic system for the amplitudes belonging to the sine- and to the cosine-excitation or a large nonlinear elliptic system for the Fourier coefficients in the linear and nonlinear case, respectively. The fast solution of the corresponding linear and nonlinear system of finite element equations is crucial for the competitiveness of this method. © 2011 Springer-Verlag Berlin Heidelberg.

  12. Domain Decomposition Solvers for Frequency-Domain Finite Element Equations

    KAUST Repository

    Copeland, Dylan

    2010-10-05

    The paper is devoted to fast iterative solvers for frequency-domain finite element equations approximating linear and nonlinear parabolic initial boundary value problems with time-harmonic excitations. Switching from the time domain to the frequency domain allows us to replace the expensive time-integration procedure by the solution of a simple linear elliptic system for the amplitudes belonging to the sine- and to the cosine-excitation or a large nonlinear elliptic system for the Fourier coefficients in the linear and nonlinear case, respectively. The fast solution of the corresponding linear and nonlinear system of finite element equations is crucial for the competitiveness of this method. © 2011 Springer-Verlag Berlin Heidelberg.

  13. A General Symbolic PDE Solver Generator: Beyond Explicit Schemes

    Directory of Open Access Journals (Sweden)

    K. Sheshadri

    2003-01-01

    Full Text Available This paper presents an extension of our Mathematica- and MathCode-based symbolic-numeric framework for solving a variety of partial differential equation (PDE problems. The main features of our earlier work, which implemented explicit finite-difference schemes, include the ability to handle (1 arbitrary number of dependent variables, (2 arbitrary dimensionality, and (3 arbitrary geometry, as well as (4 developing finite-difference schemes to any desired order of approximation. In the present paper, extensions of this framework to implicit schemes and the method of lines are discussed. While C++ code is generated, using the MathCode system for the implicit method, Modelica code is generated for the method of lines. The latter provides a preliminary PDE support for the Modelica language. Examples illustrating the various aspects of the solver generator are presented.

  14. GPU accelerated FDTD solver and its application in MRI.

    Science.gov (United States)

    Chi, J; Liu, F; Jin, J; Mason, D G; Crozier, S

    2010-01-01

    The finite difference time domain (FDTD) method is a popular technique for computational electromagnetics (CEM). The large computational power often required, however, has been a limiting factor for its applications. In this paper, we will present a graphics processing unit (GPU)-based parallel FDTD solver and its successful application to the investigation of a novel B1 shimming scheme for high-field magnetic resonance imaging (MRI). The optimized shimming scheme exhibits considerably improved transmit B(1) profiles. The GPU implementation dramatically shortened the runtime of FDTD simulation of electromagnetic field compared with its CPU counterpart. The acceleration in runtime has made such investigation possible, and will pave the way for other studies of large-scale computational electromagnetic problems in modern MRI which were previously impractical.

  15. Jump as Far as You Can [Problem Solvers: Solutions

    Science.gov (United States)

    Yigit, Melike; Bofferding, Laura; Warnock, Miranda

    2014-01-01

    The How Far Do You Think You Can Jump? activity (see EJ1174770) was completed in three different contexts: an after-school mathematics enrichment program at Woodland and Country Schools in Weston, Massachusetts; a small-group pull-out of second graders at Wren Elementary in Piedmont, South Carolina; and a family math night in Lafayette, Indiana.…

  16. Critical Thinking and the Development of Innovative Problem Solvers

    National Research Council Canada - National Science Library

    Drew, Christopher T

    2005-01-01

    .... This capability can be trained by making Critical Thinking the focus of officer education. Critical Thinking is the general cognitive skill of developing the best solution when there is not a single correct answer...

  17. A TFETI domain decomposition solver for elastoplastic problems

    Czech Academy of Sciences Publication Activity Database

    Čermák, M.; Kozubek, T.; Sysala, Stanislav; Valdman, J.

    2014-01-01

    Roč. 231, č. 1 (2014), s. 634-653 ISSN 0096-3003 Institutional support: RVO:68145535 Keywords : elastoplasticity * Total FETI domain decomposition method * Finite element method * Semismooth Newton method Subject RIV: BA - General Mathematics Impact factor: 1.551, year: 2014 http://ac.els-cdn.com/S0096300314000253/1-s2.0-S0096300314000253-main.pdf?_tid=33a29cf4-996a-11e3-8c5a-00000aacb360&acdnat=1392816896_4584697dc26cf934dcf590c63f0dbab7

  18. Nonlinear Chance Constrained Problems: Optimality Conditions, Regularization and Solvers

    Czech Academy of Sciences Publication Activity Database

    Adam, Lukáš; Branda, Martin

    2016-01-01

    Roč. 170, č. 2 (2016), s. 419-436 ISSN 0022-3239 R&D Projects: GA ČR GA15-00735S Institutional support: RVO:67985556 Keywords : Chance constrained programming * Optimality conditions * Regularization * Algorithms * Free MATLAB codes Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 1.289, year: 2016 http://library.utia.cas.cz/separaty/2016/MTR/adam-0460909.pdf

  19. Parallel time domain solvers for electrically large transient scattering problems

    KAUST Repository

    Liu, Yang; Yucel, Abdulkadir; Bagcý , Hakan; Michielssen, Eric

    2014-01-01

    scattering from perfect electrically conducting objects are obtained by enforcing electric field boundary conditions and implicitly time advance electric surface current densities by iteratively solving sparse systems of equations at all time steps. Contrary

  20. Comparison of Integer Programming (IP) Solvers for Automated Test Assembly (ATA). Research Report. ETS RR-15-05

    Science.gov (United States)

    Donoghue, John R.

    2015-01-01

    At the heart of van der Linden's approach to automated test assembly (ATA) is a linear programming/integer programming (LP/IP) problem. A variety of IP solvers are available, ranging in cost from free to hundreds of thousands of dollars. In this paper, I compare several approaches to solving the underlying IP problem. These approaches range from…

  1. AQUASOL: An efficient solver for the dipolar Poisson-Boltzmann-Langevin equation.

    Science.gov (United States)

    Koehl, Patrice; Delarue, Marc

    2010-02-14

    The Poisson-Boltzmann (PB) formalism is among the most popular approaches to modeling the solvation of molecules. It assumes a continuum model for water, leading to a dielectric permittivity that only depends on position in space. In contrast, the dipolar Poisson-Boltzmann-Langevin (DPBL) formalism represents the solvent as a collection of orientable dipoles with nonuniform concentration; this leads to a nonlinear permittivity function that depends both on the position and on the local electric field at that position. The differences in the assumptions underlying these two models lead to significant differences in the equations they generate. The PB equation is a second order, elliptic, nonlinear partial differential equation (PDE). Its response coefficients correspond to the dielectric permittivity and are therefore constant within each subdomain of the system considered (i.e., inside and outside of the molecules considered). While the DPBL equation is also a second order, elliptic, nonlinear PDE, its response coefficients are nonlinear functions of the electrostatic potential. Many solvers have been developed for the PB equation; to our knowledge, none of these can be directly applied to the DPBL equation. The methods they use may adapt to the difference; their implementations however are PBE specific. We adapted the PBE solver originally developed by Holst and Saied [J. Comput. Chem. 16, 337 (1995)] to the problem of solving the DPBL equation. This solver uses a truncated Newton method with a multigrid preconditioner. Numerical evidences suggest that it converges for the DPBL equation and that the convergence is superlinear. It is found however to be slow and greedy in memory requirement for problems commonly encountered in computational biology and computational chemistry. To circumvent these problems, we propose two variants, a quasi-Newton solver based on a simplified, inexact Jacobian and an iterative self-consistent solver that is based directly on the PBE

  2. Death with Dignity: A Tripartite Legal Response

    Science.gov (United States)

    Leblang, Theodore Raymond

    1978-01-01

    This article provides a descriptive overview of the legal problems that attend medical treatment of the terminally ill patient as well as a careful analysis of the legal vehicles that have been offered in response to these problems--the living will, the antidysthanasia contract, and right to die legislation. (Author)

  3. Essential imposition of Neumann condition in Galerkin-Legendre elliptic solvers

    CERN Document Server

    Auteri, F; Quartapelle, L

    2003-01-01

    A new Galerkin-Legendre direct spectral solver for the Neumann problem associated with Laplace and Helmholtz operators in rectangular domains is presented. The algorithm differs from other Neumann spectral solvers by the high sparsity of the matrices, exploited in conjunction with the direct product structure of the problem. The homogeneous boundary condition is satisfied exactly by expanding the unknown variable into a polynomial basis of functions which are built upon the Legendre polynomials and have a zero slope at the interval extremes. A double diagonalization process is employed pivoting around the eigenstructure of the pentadiagonal mass matrices in both directions, instead of the full stiffness matrices encountered in the classical variational formulation of the problem with a weak natural imposition of the derivative boundary condition. Nonhomogeneous Neumann data are accounted for by means of a lifting. Numerical results are given to illustrate the performance of the proposed spectral elliptic solv...

  4. The Openpipeflow Navier–Stokes solver

    Directory of Open Access Journals (Sweden)

    Ashley P. Willis

    2017-01-01

    Full Text Available Pipelines are used in a huge range of industrial processes involving fluids, and the ability to accurately predict properties of the flow through a pipe is of fundamental engineering importance. Armed with parallel MPI, Arnoldi and Newton–Krylov solvers, the Openpipeflow code can be used in a range of settings, from large-scale simulation of highly turbulent flow, to the detailed analysis of nonlinear invariant solutions (equilibria and periodic orbits and their influence on the dynamics of the flow.

  5. New multigrid solver advances in TOPS

    International Nuclear Information System (INIS)

    Falgout, R D; Brannick, J; Brezina, M; Manteuffel, T; McCormick, S

    2005-01-01

    In this paper, we highlight new multigrid solver advances in the Terascale Optimal PDE Simulations (TOPS) project in the Scientific Discovery Through Advanced Computing (SciDAC) program. We discuss two new algebraic multigrid (AMG) developments in TOPS: the adaptive smoothed aggregation method (αSA) and a coarse-grid selection algorithm based on compatible relaxation (CR). The αSA method is showing promising results in initial studies for Quantum Chromodynamics (QCD) applications. The CR method has the potential to greatly improve the applicability of AMG

  6. A finite different field solver for dipole modes

    International Nuclear Information System (INIS)

    Nelson, E.M.

    1992-08-01

    A finite element field solver for dipole modes in axisymmetric structures has been written. The second-order elements used in this formulation yield accurate mode frequencies with no spurious modes. Quasi-periodic boundaries are included to allow travelling waves in periodic structures. The solver is useful in applications requiring precise frequency calculations such as detuned accelerator structures for linear colliders. Comparisons are made with measurements and with the popular but less accurate field solver URMEL

  7. A finite element field solver for dipole modes

    International Nuclear Information System (INIS)

    Nelson, E.M.

    1992-01-01

    A finite element field solver for dipole modes in axisymmetric structures has been written. The second-order elements used in this formulation yield accurate mode frequencies with no spurious modes. Quasi-periodic boundaries are included to allow travelling waves in periodic structures. The solver is useful in applications requiring precise frequency calculations such as detuned accelerator structures for linear colliders. Comparisons are made with measurements and with the popular but less accurate field solver URMEL. (author). 7 refs., 4 figs

  8. Three-Dimensional Inverse Transport Solver Based on Compressive Sensing Technique

    Science.gov (United States)

    Cheng, Yuxiong; Wu, Hongchun; Cao, Liangzhi; Zheng, Youqi

    2013-09-01

    According to the direct exposure measurements from flash radiographic image, a compressive sensing-based method for three-dimensional inverse transport problem is presented. The linear absorption coefficients and interface locations of objects are reconstructed directly at the same time. It is always very expensive to obtain enough measurements. With limited measurements, compressive sensing sparse reconstruction technique orthogonal matching pursuit is applied to obtain the sparse coefficients by solving an optimization problem. A three-dimensional inverse transport solver is developed based on a compressive sensing-based technique. There are three features in this solver: (1) AutoCAD is employed as a geometry preprocessor due to its powerful capacity in graphic. (2) The forward projection matrix rather than Gauss matrix is constructed by the visualization tool generator. (3) Fourier transform and Daubechies wavelet transform are adopted to convert an underdetermined system to a well-posed system in the algorithm. Simulations are performed and numerical results in pseudo-sine absorption problem, two-cube problem and two-cylinder problem when using compressive sensing-based solver agree well with the reference value.

  9. Optimización con Solver

    Directory of Open Access Journals (Sweden)

    Sánchez Álvarez , I.

    1998-01-01

    Full Text Available La relevancia de los problemas de optimización en el mundo empresarial ha generado la introducción de herramientas de optimización cada vez más sofisticadas en las últimas versiones de las hojas de cálculo de utilización generalizada. Estas utilidades, conocidas habitualmente como «solvers», constituyen una alternativa a los programas especializados de optimización cuando no se trata de problemas de gran escala, presentado la ventaja de su facilidad de uso y de comunicación con el usuario final. Frontline Systems Inc es la empresa que desarrolla el «solver» de Excel, si bien existen asimismo versiones para Lotus y Quattro Pro con ligeras diferencias de uso. En su dirección de internet (www.frontsys.com se puede obtener información técnica sobre las diferentes versiones de dicha utilidad y diversos aspectos operativos del programa, algunos de los cuales se comentan en este trabajo.

  10. A sparse-grid isogeometric solver

    KAUST Repository

    Beck, Joakim

    2018-02-28

    Isogeometric Analysis (IGA) typically adopts tensor-product splines and NURBS as a basis for the approximation of the solution of PDEs. In this work, we investigate to which extent IGA solvers can benefit from the so-called sparse-grids construction in its combination technique form, which was first introduced in the early 90’s in the context of the approximation of high-dimensional PDEs.The tests that we report show that, in accordance to the literature, a sparse-grid construction can indeed be useful if the solution of the PDE at hand is sufficiently smooth. Sparse grids can also be useful in the case of non-smooth solutions when some a-priori knowledge on the location of the singularities of the solution can be exploited to devise suitable non-equispaced meshes. Finally, we remark that sparse grids can be seen as a simple way to parallelize pre-existing serial IGA solvers in a straightforward fashion, which can be beneficial in many practical situations.

  11. A sparse version of IGA solvers

    KAUST Repository

    Beck, Joakim

    2017-07-30

    Isogeometric Analysis (IGA) typically adopts tensor-product splines and NURBS as a basis for the approximation of the solution of PDEs. In this work, we investigate to which extent IGA solvers can benefit from the so-called sparse-grids construction in its combination technique form, which was first introduced in the early 90s in the context of the approximation of high-dimensional PDEs. The tests that we report show that, in accordance to the literature, a sparse grids construction can indeed be useful if the solution of the PDE at hand is sufficiently smooth. Sparse grids can also be useful in the case of non-smooth solutions when some a-priori knowledge on the location of the singularities of the solution can be exploited to devise suitable non-equispaced meshes. Finally, we remark that sparse grids can be seen as a simple way to parallelize pre-existing serial IGA solvers in a straightforward fashion, which can be beneficial in many practical situations.

  12. A sparse-grid isogeometric solver

    KAUST Repository

    Beck, Joakim; Sangalli, Giancarlo; Tamellini, Lorenzo

    2018-01-01

    Isogeometric Analysis (IGA) typically adopts tensor-product splines and NURBS as a basis for the approximation of the solution of PDEs. In this work, we investigate to which extent IGA solvers can benefit from the so-called sparse-grids construction in its combination technique form, which was first introduced in the early 90’s in the context of the approximation of high-dimensional PDEs.The tests that we report show that, in accordance to the literature, a sparse-grid construction can indeed be useful if the solution of the PDE at hand is sufficiently smooth. Sparse grids can also be useful in the case of non-smooth solutions when some a-priori knowledge on the location of the singularities of the solution can be exploited to devise suitable non-equispaced meshes. Finally, we remark that sparse grids can be seen as a simple way to parallelize pre-existing serial IGA solvers in a straightforward fashion, which can be beneficial in many practical situations.

  13. A sparse version of IGA solvers

    KAUST Repository

    Beck, Joakim; Sangalli, Giancarlo; Tamellini, Lorenzo

    2017-01-01

    Isogeometric Analysis (IGA) typically adopts tensor-product splines and NURBS as a basis for the approximation of the solution of PDEs. In this work, we investigate to which extent IGA solvers can benefit from the so-called sparse-grids construction in its combination technique form, which was first introduced in the early 90s in the context of the approximation of high-dimensional PDEs. The tests that we report show that, in accordance to the literature, a sparse grids construction can indeed be useful if the solution of the PDE at hand is sufficiently smooth. Sparse grids can also be useful in the case of non-smooth solutions when some a-priori knowledge on the location of the singularities of the solution can be exploited to devise suitable non-equispaced meshes. Finally, we remark that sparse grids can be seen as a simple way to parallelize pre-existing serial IGA solvers in a straightforward fashion, which can be beneficial in many practical situations.

  14. A fast mass spring model solver for high-resolution elastic objects

    Science.gov (United States)

    Zheng, Mianlun; Yuan, Zhiyong; Zhu, Weixu; Zhang, Guian

    2017-03-01

    Real-time simulation of elastic objects is of great importance for computer graphics and virtual reality applications. The fast mass spring model solver can achieve visually realistic simulation in an efficient way. Unfortunately, this method suffers from resolution limitations and lack of mechanical realism for a surface geometry model, which greatly restricts its application. To tackle these problems, in this paper we propose a fast mass spring model solver for high-resolution elastic objects. First, we project the complex surface geometry model into a set of uniform grid cells as cages through *cages mean value coordinate method to reflect its internal structure and mechanics properties. Then, we replace the original Cholesky decomposition method in the fast mass spring model solver with a conjugate gradient method, which can make the fast mass spring model solver more efficient for detailed surface geometry models. Finally, we propose a graphics processing unit accelerated parallel algorithm for the conjugate gradient method. Experimental results show that our method can realize efficient deformation simulation of 3D elastic objects with visual reality and physical fidelity, which has a great potential for applications in computer animation.

  15. A Comparison of Monte Carlo and Deterministic Solvers for keff and Sensitivity Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Haeck, Wim [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parsons, Donald Kent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); White, Morgan Curtis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Saller, Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Favorite, Jeffrey A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-12

    Verification and validation of our solutions for calculating the neutron reactivity for nuclear materials is a key issue to address for many applications, including criticality safety, research reactors, power reactors, and nuclear security. Neutronics codes solve variations of the Boltzmann transport equation. The two main variants are Monte Carlo versus deterministic solutions, e.g. the MCNP [1] versus PARTISN [2] codes, respectively. There have been many studies over the decades that examined the accuracy of such solvers and the general conclusion is that when the problems are well-posed, either solver can produce accurate results. However, the devil is always in the details. The current study examines the issue of self-shielding and the stress it puts on deterministic solvers. Most Monte Carlo neutronics codes use continuous-energy descriptions of the neutron interaction data that are not subject to this effect. The issue of self-shielding occurs because of the discretisation of data used by the deterministic solutions. Multigroup data used in these solvers are the average cross section and scattering parameters over an energy range. Resonances in cross sections can occur that change the likelihood of interaction by one to three orders of magnitude over a small energy range. Self-shielding is the numerical effect that the average cross section in groups with strong resonances can be strongly affected as neutrons within that material are preferentially absorbed or scattered out of the resonance energies. This affects both the average cross section and the scattering matrix.

  16. Effects of high-frequency damping on iterative convergence of implicit viscous solver

    Science.gov (United States)

    Nishikawa, Hiroaki; Nakashima, Yoshitaka; Watanabe, Norihiko

    2017-11-01

    This paper discusses effects of high-frequency damping on iterative convergence of an implicit defect-correction solver for viscous problems. The study targets a finite-volume discretization with a one parameter family of damped viscous schemes. The parameter α controls high-frequency damping: zero damping with α = 0, and larger damping for larger α (> 0). Convergence rates are predicted for a model diffusion equation by a Fourier analysis over a practical range of α. It is shown that the convergence rate attains its minimum at α = 1 on regular quadrilateral grids, and deteriorates for larger values of α. A similar behavior is observed for regular triangular grids. In both quadrilateral and triangular grids, the solver is predicted to diverge for α smaller than approximately 0.5. Numerical results are shown for the diffusion equation and the Navier-Stokes equations on regular and irregular grids. The study suggests that α = 1 and 4/3 are suitable values for robust and efficient computations, and α = 4 / 3 is recommended for the diffusion equation, which achieves higher-order accuracy on regular quadrilateral grids. Finally, a Jacobian-Free Newton-Krylov solver with the implicit solver (a low-order Jacobian approximately inverted by a multi-color Gauss-Seidel relaxation scheme) used as a variable preconditioner is recommended for practical computations, which provides robust and efficient convergence for a wide range of α.

  17. Scalable domain decomposition solvers for stochastic PDEs in high performance computing

    International Nuclear Information System (INIS)

    Desai, Ajit; Pettit, Chris; Poirel, Dominique; Sarkar, Abhijit

    2017-01-01

    Stochastic spectral finite element models of practical engineering systems may involve solutions of linear systems or linearized systems for non-linear problems with billions of unknowns. For stochastic modeling, it is therefore essential to design robust, parallel and scalable algorithms that can efficiently utilize high-performance computing to tackle such large-scale systems. Domain decomposition based iterative solvers can handle such systems. And though these algorithms exhibit excellent scalabilities, significant algorithmic and implementational challenges exist to extend them to solve extreme-scale stochastic systems using emerging computing platforms. Intrusive polynomial chaos expansion based domain decomposition algorithms are extended here to concurrently handle high resolution in both spatial and stochastic domains using an in-house implementation. Sparse iterative solvers with efficient preconditioners are employed to solve the resulting global and subdomain level local systems through multi-level iterative solvers. We also use parallel sparse matrix–vector operations to reduce the floating-point operations and memory requirements. Numerical and parallel scalabilities of these algorithms are presented for the diffusion equation having spatially varying diffusion coefficient modeled by a non-Gaussian stochastic process. Scalability of the solvers with respect to the number of random variables is also investigated.

  18. Graph Grammar-Based Multi-Frontal Parallel Direct Solver for Two-Dimensional Isogeometric Analysis

    KAUST Repository

    Kuźnik, Krzysztof

    2012-06-02

    This paper introduces the graph grammar based model for developing multi-thread multi-frontal parallel direct solver for two dimensional isogeometric finite element method. Execution of the solver algorithm has been expressed as the sequence of graph grammar productions. At the beginning productions construct the elimination tree with leaves corresponding to finite elements. Following sequence of graph grammar productions generates element frontal matri-ces at leaf nodes, merges matrices at parent nodes and eliminates rows corresponding to fully assembled degrees of freedom. Finally, there are graph grammar productions responsible for root problem solution and recursive backward substitutions. Expressing the solver algorithm by graph grammar productions allows us to explore the concurrency of the algorithm. The graph grammar productions are grouped into sets of independent tasks that can be executed concurrently. The resulting concurrent multi-frontal solver algorithm is implemented and tested on NVIDIA GPU, providing O(NlogN) execution time complexity where N is the number of degrees of freedom. We have confirmed this complexity by solving up to 1 million of degrees of freedom with 448 cores GPU.

  19. 我国石油企业海外并购的法律问题浅析%A Simple Analysis of the Legal Problems in China’s Petroleum Enterprise Overseas Merger & Acquisition

    Institute of Scientific and Technical Information of China (English)

    王璐

    2012-01-01

    分析了我国石油企业实施海外并购战略的必然性以及目前并购的现状和趋势,重点分析了海外并购中遇到的法律问题,并提出了有关的措施和建议。%The article analyzes the necessity for China’s petroleum enterprises to implement overseas merger acquisition strategy as well as current merger acquisition status and its development trends,emphatically analyzes the legal problems encountered in overseas merger acquisition and puts forward relevant measures and suggestions.

  20. Legal Radiopathology

    International Nuclear Information System (INIS)

    Andrade Lima, L. de

    1986-01-01

    The author comments about the knowledge evolution about radioactivity and describes the most important chemical elements capable of discharging it and all the types of radioactivity according with Mendelejef's classification. He analyses the celular sensibility related to many variables, listing the biological effects that may happen depending on the quantity of radiation and exposition time to radiation. He also calls attention to procedures of dosimetry and radioprotection that must be done when anatomo-pathological examination of body fluids, discharges and tissues are carried out, stressing that protective clothing must be wear, decontamination or to make useless the material involved are important to get the job done. A description of the appropriated conditions to perform autopsy, to anoint and to cremate contaminated bodies and the procedures used by the Navy Hospital Marcilio Dias service of anatomo-pathology, Instituto de Radioprotecao e Dosimetria (IRD) and Comissao Nacional de Energia Nuclear (CNEN) is given, based on the experience gained in performing necropsy of dead patients and one anatomo-pathological examination of upper limb amputated inside the surgical room. He finishes describing the macroscopic injuries observed and listing the instrumental used, the reports made, giving details about the necropsy carried out and answering medical-legal matters. (author)

  1. An Unsplit Monte-Carlo solver for the resolution of the linear Boltzmann equation coupled to (stiff) Bateman equations

    Science.gov (United States)

    Bernede, Adrien; Poëtte, Gaël

    2018-02-01

    In this paper, we are interested in the resolution of the time-dependent problem of particle transport in a medium whose composition evolves with time due to interactions. As a constraint, we want to use of Monte-Carlo (MC) scheme for the transport phase. A common resolution strategy consists in a splitting between the MC/transport phase and the time discretization scheme/medium evolution phase. After going over and illustrating the main drawbacks of split solvers in a simplified configuration (monokinetic, scalar Bateman problem), we build a new Unsplit MC (UMC) solver improving the accuracy of the solutions, avoiding numerical instabilities, and less sensitive to time discretization. The new solver is essentially based on a Monte Carlo scheme with time dependent cross sections implying the on-the-fly resolution of a reduced model for each MC particle describing the time evolution of the matter along their flight path.

  2. Stochastic Partial Differential Equation Solver for Hydroacoustic Modeling: Improvements to Paracousti Sound Propagation Solver

    Science.gov (United States)

    Preston, L. A.

    2017-12-01

    Marine hydrokinetic (MHK) devices offer a clean, renewable alternative energy source for the future. Responsible utilization of MHK devices, however, requires that the effects of acoustic noise produced by these devices on marine life and marine-related human activities be well understood. Paracousti is a 3-D full waveform acoustic modeling suite that can accurately propagate MHK noise signals in the complex bathymetry found in the near-shore to open ocean environment and considers real properties of the seabed, water column, and air-surface interface. However, this is a deterministic simulation that assumes the environment and source are exactly known. In reality, environmental and source characteristics are often only known in a statistical sense. Thus, to fully characterize the expected noise levels within the marine environment, this uncertainty in environmental and source factors should be incorporated into the acoustic simulations. One method is to use Monte Carlo (MC) techniques where simulation results from a large number of deterministic solutions are aggregated to provide statistical properties of the output signal. However, MC methods can be computationally prohibitive since they can require tens of thousands or more simulations to build up an accurate representation of those statistical properties. An alternative method, using the technique of stochastic partial differential equations (SPDE), allows computation of the statistical properties of output signals at a small fraction of the computational cost of MC. We are developing a SPDE solver for the 3-D acoustic wave propagation problem called Paracousti-UQ to help regulators and operators assess the statistical properties of environmental noise produced by MHK devices. In this presentation, we present the SPDE method and compare statistical distributions of simulated acoustic signals in simple models to MC simulations to show the accuracy and efficiency of the SPDE method. Sandia National Laboratories

  3. GPU TECHNOLOGIES EMBODIED IN PARALLEL SOLVERS OF LINEAR ALGEBRAIC EQUATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Sidorov Alexander Vladimirovich

    2012-10-01

    Full Text Available The author reviews existing shareware solvers that are operated by graphical computer devices. The purpose of this review is to explore the opportunities and limitations of the above parallel solvers applicable for resolution of linear algebraic problems that arise at Research and Educational Centre of Computer Modeling at MSUCE, and Research and Engineering Centre STADYO. The author has explored new applications of the GPU in the PETSc suite and compared them with the results generated absent of the GPU. The research is performed within the CUSP library developed to resolve the problems of linear algebra through the application of GPU. The author has also reviewed the new MAGMA project which is analogous to LAPACK for the GPU.

  4. Domain decomposition methods for core calculations using the MINOS solver

    International Nuclear Information System (INIS)

    Guerin, P.; Baudron, A. M.; Lautard, J. J.

    2007-01-01

    Cell by cell homogenized transport calculations of an entire nuclear reactor core are currently too expensive for industrial applications, even if a simplified transport (SPn) approximation is used. In order to take advantage of parallel computers, we propose here two domain decomposition methods using the mixed dual finite element solver MINOS. The first one is a modal synthesis method on overlapping sub-domains: several Eigenmodes solutions of a local problem on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second one is an iterative method based on non-overlapping domain decomposition with Robin interface conditions. At each iteration, we solve the problem on each sub-domain with the interface conditions given by the solutions on the close sub-domains estimated at the previous iteration. For these two methods, we give numerical results which demonstrate their accuracy and their efficiency for the diffusion model on realistic 2D and 3D cores. (authors)

  5. Legal technique: approaches to section on types

    Directory of Open Access Journals (Sweden)

    І. Д. Шутак

    2015-11-01

    Full Text Available Legal technique is a branch of knowledge about the rules of doing legal work and creating in the process a variety of legal documents, which had previously been part of the theory of law. In modern conditions of the legal technique are isolated in a separate branch of legal science, focused on solving practical problems. The purpose of this article is to analyze the types of legal techniques, in particular, on the basis of theoretical propositions about legal technique to allocate substantial characteristics and types of legal technique. O. Malko and M. Matuzov consider legal technique as a set of rules, techniques, methods of preparation, creation, registration of legal documents, their classification and accounting for their excellence, efficient use. A similar meaning is investing in this concept Alekseev, determining that the legal technique is a set of tools and techniques used in accordance with accepted rules in the formulation and systematization of legal acts to ensure their perfection. So, legal technique – theoretical and applied legal science, which studies the regularities of rational legal practice in the creation, interpretation and implementation of law. In relation to the type of legal techniques in the literature proposed different classifications. For example, G. Muromtsev technique, which is used only in the field of law, divide on the technique of law-making (legislative technique, technique of law enforcement, interpretation, technique of judicial speech, interrogation, notarial activities. V. Kartashov shared legal technique on law making and enforcement (prorealtime, interpretive yourself and prevacidrebatezw, judicial or investigative, prosecutorial, and the like. Some authors clearly indicate that the criterion by which to distinguish types of legal techniques. So, S. Alekseev notes that legal technique is classified from the point of view of the legal nature of the act made on: a techniques of legal acts; b the

  6. The Quantum Mechanics Solver How to Apply Quantum Theory to Modern Physics

    CERN Document Server

    Basdevant, Jean-Louis

    2006-01-01

    The Quantum Mechanics Solver grew from topics which are part of the final examination in quantum theory at the Ecole Polytechnique at Palaiseau near Paris, France. The aim of the text is to guide the student towards applying quantum mechanics to research problems in fields such as atomic and molecular physics, condensed matter physics, and laser physics. Advanced undergraduates and graduate students will find a rich and challenging source for improving their skills in this field.

  7. A LAGRANGIAN GAUSS-NEWTON-KRYLOV SOLVER FOR MASS- AND INTENSITY-PRESERVING DIFFEOMORPHIC IMAGE REGISTRATION.

    Science.gov (United States)

    Mang, Andreas; Ruthotto, Lars

    2017-01-01

    We present an efficient solver for diffeomorphic image registration problems in the framework of Large Deformations Diffeomorphic Metric Mappings (LDDMM). We use an optimal control formulation, in which the velocity field of a hyperbolic PDE needs to be found such that the distance between the final state of the system (the transformed/transported template image) and the observation (the reference image) is minimized. Our solver supports both stationary and non-stationary (i.e., transient or time-dependent) velocity fields. As transformation models, we consider both the transport equation (assuming intensities are preserved during the deformation) and the continuity equation (assuming mass-preservation). We consider the reduced form of the optimal control problem and solve the resulting unconstrained optimization problem using a discretize-then-optimize approach. A key contribution is the elimination of the PDE constraint using a Lagrangian hyperbolic PDE solver. Lagrangian methods rely on the concept of characteristic curves. We approximate these curves using a fourth-order Runge-Kutta method. We also present an efficient algorithm for computing the derivatives of the final state of the system with respect to the velocity field. This allows us to use fast Gauss-Newton based methods. We present quickly converging iterative linear solvers using spectral preconditioners that render the overall optimization efficient and scalable. Our method is embedded into the image registration framework FAIR and, thus, supports the most commonly used similarity measures and regularization functionals. We demonstrate the potential of our new approach using several synthetic and real world test problems with up to 14.7 million degrees of freedom.

  8. The Application Strategy of Iterative Solution Methodology to Matrix Equations in Hydraulic Solver Package, SPACE

    International Nuclear Information System (INIS)

    Na, Y. W.; Park, C. E.; Lee, S. Y.

    2009-01-01

    As a part of the Ministry of Knowledge Economy (MKE) project, 'Development of safety analysis codes for nuclear power plants', KOPEC has been developing the hydraulic solver code package applicable to the safety analyses of nuclear power plants (NPP's). The matrices of the hydraulic solver are usually sparse and may be asymmetric. In the earlier stage of this project, typical direct matrix solver packages MA48 and MA28 had been tested as matrix solver for the hydraulic solver code, SPACE. The selection was based on the reasonably reliable performance experience from their former version MA18 in RELAP computer code. In the later stage of this project, the iterative methodologies have been being tested in the SPACE code. Among a few candidate iterative solution methodologies tested so far, the biconjugate gradient stabilization methodology (BICGSTAB) has shown the best performance in the applicability test and in the application to the SPACE code. Regardless of all the merits of using the direct solver packages, there are some other aspects of tackling the iterative solution methodologies. The algorithm is much simpler and easier to handle. The potential problems related to the robustness of the iterative solution methodologies have been resolved by applying pre-conditioning methods adjusted and modified as appropriate to the application in the SPACE code. The application strategy of conjugate gradient method was introduced in detail by Schewchuk, Golub and Saad in the middle of 1990's. The application of his methodology to nuclear engineering in Korea started about the same time and is still going on and there are quite a few examples of application to neutronics. Besides, Yang introduced a conjugate gradient method programmed in C++ language. The purpose of this study is to assess the performance and behavior of the iterative solution methodology compared to those of the direct solution methodology still being preferred due to its robustness and reliability. The

  9. A RADIATION TRANSFER SOLVER FOR ATHENA USING SHORT CHARACTERISTICS

    International Nuclear Information System (INIS)

    Davis, Shane W.; Stone, James M.; Jiang Yanfei

    2012-01-01

    We describe the implementation of a module for the Athena magnetohydrodynamics (MHD) code that solves the time-independent, multi-frequency radiative transfer (RT) equation on multidimensional Cartesian simulation domains, including scattering and non-local thermodynamic equilibrium (LTE) effects. The module is based on well known and well tested algorithms developed for modeling stellar atmospheres, including the method of short characteristics to solve the RT equation, accelerated Lambda iteration to handle scattering and non-LTE effects, and parallelization via domain decomposition. The module serves several purposes: it can be used to generate spectra and images, to compute a variable Eddington tensor (VET) for full radiation MHD simulations, and to calculate the heating and cooling source terms in the MHD equations in flows where radiation pressure is small compared with gas pressure. For the latter case, the module is combined with the standard MHD integrators using operator splitting: we describe this approach in detail, including a new constraint on the time step for stability due to radiation diffusion modes. Implementation of the VET method for radiation pressure dominated flows is described in a companion paper. We present results from a suite of test problems for both the RT solver itself and for dynamical problems that include radiative heating and cooling. These tests demonstrate that the radiative transfer solution is accurate and confirm that the operator split method is stable, convergent, and efficient for problems of interest. We demonstrate there is no need to adopt ad hoc assumptions of questionable accuracy to solve RT problems in concert with MHD: the computational cost for our general-purpose module for simple (e.g., LTE gray) problems can be comparable to or less than a single time step of Athena's MHD integrators, and only few times more expensive than that for more general (non-LTE) problems.

  10. An accurate, fast, and scalable solver for high-frequency wave propagation

    Science.gov (United States)

    Zepeda-Núñez, L.; Taus, M.; Hewett, R.; Demanet, L.

    2017-12-01

    In many science and engineering applications, solving time-harmonic high-frequency wave propagation problems quickly and accurately is of paramount importance. For example, in geophysics, particularly in oil exploration, such problems can be the forward problem in an iterative process for solving the inverse problem of subsurface inversion. It is important to solve these wave propagation problems accurately in order to efficiently obtain meaningful solutions of the inverse problems: low order forward modeling can hinder convergence. Additionally, due to the volume of data and the iterative nature of most optimization algorithms, the forward problem must be solved many times. Therefore, a fast solver is necessary to make solving the inverse problem feasible. For time-harmonic high-frequency wave propagation, obtaining both speed and accuracy is historically challenging. Recently, there have been many advances in the development of fast solvers for such problems, including methods which have linear complexity with respect to the number of degrees of freedom. While most methods scale optimally only in the context of low-order discretizations and smooth wave speed distributions, the method of polarized traces has been shown to retain optimal scaling for high-order discretizations, such as hybridizable discontinuous Galerkin methods and for highly heterogeneous (and even discontinuous) wave speeds. The resulting fast and accurate solver is consequently highly attractive for geophysical applications. To date, this method relies on a layered domain decomposition together with a preconditioner applied in a sweeping fashion, which has limited straight-forward parallelization. In this work, we introduce a new version of the method of polarized traces which reveals more parallel structure than previous versions while preserving all of its other advantages. We achieve this by further decomposing each layer and applying the preconditioner to these new components separately and

  11. A comparison of SuperLU solvers on the intel MIC architecture

    Science.gov (United States)

    Tuncel, Mehmet; Duran, Ahmet; Celebi, M. Serdar; Akaydin, Bora; Topkaya, Figen O.

    2016-10-01

    In many science and engineering applications, problems may result in solving a sparse linear system AX=B. For example, SuperLU_MCDT, a linear solver, was used for the large penta-diagonal matrices for 2D problems and hepta-diagonal matrices for 3D problems, coming from the incompressible blood flow simulation (see [1]). It is important to test the status and potential improvements of state-of-the-art solvers on new technologies. In this work, sequential, multithreaded and distributed versions of SuperLU solvers (see [2]) are examined on the Intel Xeon Phi coprocessors using offload programming model at the EURORA cluster of CINECA in Italy. We consider a portfolio of test matrices containing patterned matrices from UFMM ([3]) and randomly located matrices. This architecture can benefit from high parallelism and large vectors. We find that the sequential SuperLU benefited up to 45 % performance improvement from the offload programming depending on the sparse matrix type and the size of transferred and processed data.

  12. ELSI: A unified software interface for Kohn-Sham electronic structure solvers

    Science.gov (United States)

    Yu, Victor Wen-zhe; Corsetti, Fabiano; García, Alberto; Huhn, William P.; Jacquelin, Mathias; Jia, Weile; Lange, Björn; Lin, Lin; Lu, Jianfeng; Mi, Wenhui; Seifitokaldani, Ali; Vázquez-Mayagoitia, Álvaro; Yang, Chao; Yang, Haizhao; Blum, Volker

    2018-01-01

    Solving the electronic structure from a generalized or standard eigenproblem is often the bottleneck in large scale calculations based on Kohn-Sham density-functional theory. This problem must be addressed by essentially all current electronic structure codes, based on similar matrix expressions, and by high-performance computation. We here present a unified software interface, ELSI, to access different strategies that address the Kohn-Sham eigenvalue problem. Currently supported algorithms include the dense generalized eigensolver library ELPA, the orbital minimization method implemented in libOMM, and the pole expansion and selected inversion (PEXSI) approach with lower computational complexity for semilocal density functionals. The ELSI interface aims to simplify the implementation and optimal use of the different strategies, by offering (a) a unified software framework designed for the electronic structure solvers in Kohn-Sham density-functional theory; (b) reasonable default parameters for a chosen solver; (c) automatic conversion between input and internal working matrix formats, and in the future (d) recommendation of the optimal solver depending on the specific problem. Comparative benchmarks are shown for system sizes up to 11,520 atoms (172,800 basis functions) on distributed memory supercomputing architectures.

  13. Robust large-scale parallel nonlinear solvers for simulations.

    Energy Technology Data Exchange (ETDEWEB)

    Bader, Brett William; Pawlowski, Roger Patrick; Kolda, Tamara Gibson (Sandia National Laboratories, Livermore, CA)

    2005-11-01

    This report documents research to develop robust and efficient solution techniques for solving large-scale systems of nonlinear equations. The most widely used method for solving systems of nonlinear equations is Newton's method. While much research has been devoted to augmenting Newton-based solvers (usually with globalization techniques), little has been devoted to exploring the application of different models. Our research has been directed at evaluating techniques using different models than Newton's method: a lower order model, Broyden's method, and a higher order model, the tensor method. We have developed large-scale versions of each of these models and have demonstrated their use in important applications at Sandia. Broyden's method replaces the Jacobian with an approximation, allowing codes that cannot evaluate a Jacobian or have an inaccurate Jacobian to converge to a solution. Limited-memory methods, which have been successful in optimization, allow us to extend this approach to large-scale problems. We compare the robustness and efficiency of Newton's method, modified Newton's method, Jacobian-free Newton-Krylov method, and our limited-memory Broyden method. Comparisons are carried out for large-scale applications of fluid flow simulations and electronic circuit simulations. Results show that, in cases where the Jacobian was inaccurate or could not be computed, Broyden's method converged in some cases where Newton's method failed to converge. We identify conditions where Broyden's method can be more efficient than Newton's method. We also present modifications to a large-scale tensor method, originally proposed by Bouaricha, for greater efficiency, better robustness, and wider applicability. Tensor methods are an alternative to Newton-based methods and are based on computing a step based on a local quadratic model rather than a linear model. The advantage of Bouaricha's method is that it can use any

  14. Performance of the block-Krylov energy group solvers in Jaguar

    Energy Technology Data Exchange (ETDEWEB)

    Watson, A. M.; Kennedy, R. A. [Knolls Atomic Power Laboratory, Bechtel Marine Propulsion Corporation, P.O. Box 1072, Schenectady, NY 12301-1072 (United States)

    2012-07-01

    A new method of coupling the inner and outer iterations for deterministic transport problems is proposed. This method is termed the Multigroup Energy Blocking Method (MEBM) and has been implemented in the deterministic transport solver Jaguar, which is currently under development at KAPL. The method is derived for both fixed-source and eigenvalue problems. The method is then applied to a PWR pin cell model, both in fixed-source mode and eigenvalue mode. The results show that the MEBM improves the convergence of both types of problems when applied to the thermal (up-scattering) groups. (authors)

  15. Parallelization of Unsteady Adaptive Mesh Refinement for Unstructured Navier-Stokes Solvers

    Science.gov (United States)

    Schwing, Alan M.; Nompelis, Ioannis; Candler, Graham V.

    2014-01-01

    This paper explores the implementation of the MPI parallelization in a Navier-Stokes solver using adaptive mesh re nement. Viscous and inviscid test problems are considered for the purpose of benchmarking, as are implicit and explicit time advancement methods. The main test problem for comparison includes e ects from boundary layers and other viscous features and requires a large number of grid points for accurate computation. Ex- perimental validation against double cone experiments in hypersonic ow are shown. The adaptive mesh re nement shows promise for a staple test problem in the hypersonic com- munity. Extension to more advanced techniques for more complicated ows is described.

  16. Conducting Automated Test Assembly Using the Premium Solver Platform Version 7.0 with Microsoft Excel and the Large-Scale LP/QP Solver Engine Add-In

    Science.gov (United States)

    Cor, Ken; Alves, Cecilia; Gierl, Mark J.

    2008-01-01

    This review describes and evaluates a software add-in created by Frontline Systems, Inc., that can be used with Microsoft Excel 2007 to solve large, complex test assembly problems. The combination of Microsoft Excel 2007 with the Frontline Systems Premium Solver Platform is significant because Microsoft Excel is the most commonly used spreadsheet…

  17. Legal Philosophy - Five Questions

    DEFF Research Database (Denmark)

    This collection gathers together a host of the most eminent contemporary legal philosophers, who writes about their take on legal philosophy, its fundamental questions and potential.......This collection gathers together a host of the most eminent contemporary legal philosophers, who writes about their take on legal philosophy, its fundamental questions and potential....

  18. Grammar-Based Multi-Frontal Solver for One Dimensional Isogeometric Analysis with Multiple Right-Hand-Sides

    KAUST Repository

    Kuźnik, Krzysztof

    2013-06-01

    This paper introduces a grammar-based model for developing a multi-thread multi-frontal parallel direct solver for one- dimensional isogeometric finite element method. The model includes the integration of B-splines for construction of the element local matrices and the multi-frontal solver algorithm. The integration and the solver algorithm are partitioned into basic indivisible tasks, namely the grammar productions, that can be executed squentially. The partial order of execution of the basic tasks is analyzed to provide the scheduling for the execution of the concurrent integration and multi-frontal solver algo- rithm. This graph grammar analysis allows for optimal concurrent execution of all tasks. The model has been implemented and tested on NVIDIA CUDA GPU, delivering logarithmic execution time for linear, quadratic, cubic and higher order B-splines. Thus, the CUDA implementation delivers the optimal performance predicted by our graph grammar analysis. We utilize the solver for multiple right hand sides related to the solution of non-stationary or inverse problems.

  19. GENASIS Mathematics : Object-oriented manifolds, operations, and solvers for large-scale physics simulations

    Science.gov (United States)

    Cardall, Christian Y.; Budiardja, Reuben D.

    2018-01-01

    The large-scale computer simulation of a system of physical fields governed by partial differential equations requires some means of approximating the mathematical limit of continuity. For example, conservation laws are often treated with a 'finite-volume' approach in which space is partitioned into a large number of small 'cells,' with fluxes through cell faces providing an intuitive discretization modeled on the mathematical definition of the divergence operator. Here we describe and make available Fortran 2003 classes furnishing extensible object-oriented implementations of simple meshes and the evolution of generic conserved currents thereon, along with individual 'unit test' programs and larger example problems demonstrating their use. These classes inaugurate the Mathematics division of our developing astrophysics simulation code GENASIS (Gen eral A strophysical Si mulation S ystem), which will be expanded over time to include additional meshing options, mathematical operations, solver types, and solver variations appropriate for many multiphysics applications.

  20. A Massively Parallel Solver for the Mechanical Harmonic Analysis of Accelerator Cavities

    International Nuclear Information System (INIS)

    2015-01-01

    ACE3P is a 3D massively parallel simulation suite that developed at SLAC National Accelerator Laboratory that can perform coupled electromagnetic, thermal and mechanical study. Effectively utilizing supercomputer resources, ACE3P has become a key simulation tool for particle accelerator R and D. A new frequency domain solver to perform mechanical harmonic response analysis of accelerator components is developed within the existing parallel framework. This solver is designed to determine the frequency response of the mechanical system to external harmonic excitations for time-efficient accurate analysis of the large-scale problems. Coupled with the ACE3P electromagnetic modules, this capability complements a set of multi-physics tools for a comprehensive study of microphonics in superconducting accelerating cavities in order to understand the RF response and feedback requirements for the operational reliability of a particle accelerator. (auth)

  1. Constraint Solver Techniques for Implementing Precise and Scalable Static Program Analysis

    DEFF Research Database (Denmark)

    Zhang, Ye

    solver using unification we could make a program analysis easier to design and implement, much more scalable, and still as precise as expected. We present an inclusion constraint language with the explicit equality constructs for specifying program analysis problems, and a parameterized framework...... developers to build reliable software systems more quickly and with fewer bugs or security defects. While designing and implementing a program analysis remains a hard work, making it both scalable and precise is even more challenging. In this dissertation, we show that with a general inclusion constraint...... data flow analyses for C language, we demonstrate a large amount of equivalences could be detected by off-line analyses, and they could then be used by a constraint solver to significantly improve the scalability of an analysis without sacrificing any precision....

  2. Solving non-linear Horn clauses using a linear Horn clause solver

    DEFF Research Database (Denmark)

    Kafle, Bishoksan; Gallagher, John Patrick; Ganty, Pierre

    2016-01-01

    In this paper we show that checking satisfiability of a set of non-linear Horn clauses (also called a non-linear Horn clause program) can be achieved using a solver for linear Horn clauses. We achieve this by interleaving a program transformation with a satisfiability checker for linear Horn...... clauses (also called a solver for linear Horn clauses). The program transformation is based on the notion of tree dimension, which we apply to a set of non-linear clauses, yielding a set whose derivation trees have bounded dimension. Such a set of clauses can be linearised. The main algorithm...... dimension. We constructed a prototype implementation of this approach and performed some experiments on a set of verification problems, which shows some promise....

  3. Learning Domain-Specific Heuristics for Answer Set Solvers

    OpenAIRE

    Balduccini, Marcello

    2010-01-01

    In spite of the recent improvements in the performance of Answer Set Programming (ASP) solvers, when the search space is sufficiently large, it is still possible for the search algorithm to mistakenly focus on areas of the search space that contain no solutions or very few. When that happens, performance degrades substantially, even to the point that the solver may need to be terminated before returning an answer. This prospect is a concern when one is considering using such a solver in an in...

  4. A non-conforming 3D spherical harmonic transport solver

    Energy Technology Data Exchange (ETDEWEB)

    Van Criekingen, S. [Commissariat a l' Energie Atomique CEA-Saclay, DEN/DM2S/SERMA/LENR Bat 470, 91191 Gif-sur-Yvette, Cedex (France)

    2006-07-01

    A new 3D transport solver for the time-independent Boltzmann transport equation has been developed. This solver is based on the second-order even-parity form of the transport equation. The angular discretization is performed through the expansion of the angular neutron flux in spherical harmonics (PN method). The novelty of this solver is the use of non-conforming finite elements for the spatial discretization. Such elements lead to a discontinuous flux approximation. This interface continuity requirement relaxation property is shared with mixed-dual formulations such as the ones based on Raviart-Thomas finite elements. Encouraging numerical results are presented. (authors)

  5. A non-conforming 3D spherical harmonic transport solver

    International Nuclear Information System (INIS)

    Van Criekingen, S.

    2006-01-01

    A new 3D transport solver for the time-independent Boltzmann transport equation has been developed. This solver is based on the second-order even-parity form of the transport equation. The angular discretization is performed through the expansion of the angular neutron flux in spherical harmonics (PN method). The novelty of this solver is the use of non-conforming finite elements for the spatial discretization. Such elements lead to a discontinuous flux approximation. This interface continuity requirement relaxation property is shared with mixed-dual formulations such as the ones based on Raviart-Thomas finite elements. Encouraging numerical results are presented. (authors)

  6. “微信营销”存在的问题及其法律规制%The problems of "WeChat marketing" and its legal regulation

    Institute of Scientific and Technical Information of China (English)

    甫鲁西·齐美革

    2016-01-01

    In recent years,with the development and update of mobile Internet technology,and the rapid popularity of smart phones,the WeChat business,WeChat marketing also arises at the historic moment. Behind the strong mo-mentum of Wechat business development,many disadvantages exist in the WeChat marketing and trading,the legal issues and risks also gradually highlights. The paper expounds the WeChat business and WeChat marketing through the interpretation of the legal characteristics,and analyzes problems existing in the marketing and trading,such as false advertising overrun,purchasing agency of fake goods,and difficulty of rights protection. It puts forward the pro-posal from the aspects of legal regulation:using the existing legal norms,speeding up the electronic commerce legis-lation,and strengthening the administrative regulation.%近些年随着移动互联网技术的发展更新和智能手机加快普及,微商、微信营销也应运而生。微商强劲发展势头的背后,微信营销及交易存在诸多弊端,其中的法律问题和风险也逐渐凸显。文章通过对微信和微商以及微信营销的法律特征入手进行阐释,对微信营销及交易中存在的虚假广告泛滥成灾、微信诈骗和假货代购问题严重、买家维权困难等问题进行分析,从法律规制等角度提出利用现有的法律规范,并加快专门的电子商务立法、加大行政监管力度等建议。

  7. Artificial intelligence approach to legal reasoning

    International Nuclear Information System (INIS)

    Gardner, A.V.D.L.

    1984-01-01

    For artificial intelligence, understanding the forms of human reasoning is a central goal. Legal reasoning is a form that makes a new set of demands on artificial intelligence methods. Most importantly, a computer program that reasons about legal problems must be able to distinguish between questions it is competent to answer and questions that human lawyers could seriously argue either way. In addition, a program for analyzing legal problems should be able to use both general legal rules and decisions in past cases; and it should be able to work with technical concepts that are only partly defined and subject to shifts of meaning. Each of these requirements has wider applications in artificial intelligence, beyond the legal domain. This dissertation presents a computational framework for legal reasoning, within which such requirements can be accommodated. The development of the framework draws significantly on the philosophy of law, in which the elucidation of legal reasoning is an important topic. A key element of the framework is the legal distinction between hard cases and clear cases. In legal writing, this distinction has been taken for granted more often than it has been explored. Here, some initial heuristics are proposed by which a program might make the distinction

  8. libmpdata++ 1.0: a library of parallel MPDATA solvers for systems of generalised transport equations

    Science.gov (United States)

    Jaruga, A.; Arabas, S.; Jarecka, D.; Pawlowska, H.; Smolarkiewicz, P. K.; Waruszewski, M.

    2015-04-01

    This paper accompanies the first release of libmpdata++, a C++ library implementing the multi-dimensional positive-definite advection transport algorithm (MPDATA) on regular structured grid. The library offers basic numerical solvers for systems of generalised transport equations. The solvers are forward-in-time, conservative and non-linearly stable. The libmpdata++ library covers the basic second-order-accurate formulation of MPDATA, its third-order variant, the infinite-gauge option for variable-sign fields and a flux-corrected transport extension to guarantee non-oscillatory solutions. The library is equipped with a non-symmetric variational elliptic solver for implicit evaluation of pressure gradient terms. All solvers offer parallelisation through domain decomposition using shared-memory parallelisation. The paper describes the library programming interface, and serves as a user guide. Supported options are illustrated with benchmarks discussed in the MPDATA literature. Benchmark descriptions include code snippets as well as quantitative representations of simulation results. Examples of applications include homogeneous transport in one, two and three dimensions in Cartesian and spherical domains; a shallow-water system compared with analytical solution (originally derived for a 2-D case); and a buoyant convection problem in an incompressible Boussinesq fluid with interfacial instability. All the examples are implemented out of the library tree. Regardless of the differences in the problem dimensionality, right-hand-side terms, boundary conditions and parallelisation approach, all the examples use the same unmodified library, which is a key goal of libmpdata++ design. The design, based on the principle of separation of concerns, prioritises the user and developer productivity. The libmpdata++ library is implemented in C++, making use of the Blitz++ multi-dimensional array containers, and is released as free/libre and open-source software.

  9. libmpdata++ 0.1: a library of parallel MPDATA solvers for systems of generalised transport equations

    Science.gov (United States)

    Jaruga, A.; Arabas, S.; Jarecka, D.; Pawlowska, H.; Smolarkiewicz, P. K.; Waruszewski, M.

    2014-11-01

    This paper accompanies first release of libmpdata++, a C++ library implementing the Multidimensional Positive-Definite Advection Transport Algorithm (MPDATA). The library offers basic numerical solvers for systems of generalised transport equations. The solvers are forward-in-time, conservative and non-linearly stable. The libmpdata++ library covers the basic second-order-accurate formulation of MPDATA, its third-order variant, the infinite-gauge option for variable-sign fields and a flux-corrected transport extension to guarantee non-oscillatory solutions. The library is equipped with a non-symmetric variational elliptic solver for implicit evaluation of pressure gradient terms. All solvers offer parallelisation through domain decomposition using shared-memory parallelisation. The paper describes the library programming interface, and serves as a user guide. Supported options are illustrated with benchmarks discussed in the MPDATA literature. Benchmark descriptions include code snippets as well as quantitative representations of simulation results. Examples of applications include: homogeneous transport in one, two and three dimensions in Cartesian and spherical domains; shallow-water system compared with analytical solution (originally derived for a 2-D case); and a buoyant convection problem in an incompressible Boussinesq fluid with interfacial instability. All the examples are implemented out of the library tree. Regardless of the differences in the problem dimensionality, right-hand-side terms, boundary conditions and parallelisation approach, all the examples use the same unmodified library, which is a key goal of libmpdata++ design. The design, based on the principle of separation of concerns, prioritises the user and developer productivity. The libmpdata++ library is implemented in C++, making use of the Blitz++ multi-dimensional array containers, and is released as free/libre and open-source software.

  10. Defining Legal Moralism

    DEFF Research Database (Denmark)

    Thaysen, Jens Damgaard

    2015-01-01

    This paper discusses how legal moralism should be defined. It is argued that legal moralism should be defined as the position that “For any X, it is always a pro tanto reason for justifiably imposing legal regulation on X that X is morally wrong (where “morally wrong” is not conceptually equivalent...... to “harmful”)”. Furthermore, a distinction between six types of legal moralism is made. The six types are grouped according to whether they are concerned with the enforcement of positive or critical morality, and whether they are concerned with criminalising, legally restricting, or refraining from legally...... protecting morally wrong behaviour. This is interesting because not all types of legal moralism are equally vulnerable to the different critiques of legal moralism that have been put forth. Indeed, I show that some interesting types of legal moralism have not been criticised at all....

  11. Problem solving stages in the five square problem

    Directory of Open Access Journals (Sweden)

    Anna eFedor

    2015-08-01

    Full Text Available According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviourally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were in. 101 participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and 67 of them also had the possibility of reporting impasse while working on the task. We have found that 49% (19 out of 39 of the solvers and 13% (8 out of 62 of the non-solvers followed the classic four-stage model of insight. The rest of the participants had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model must be extended to explain variability on the individual level. We provide a model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviourally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behaviour to verify insight theory.

  12. Regional Legal Assistance

    Directory of Open Access Journals (Sweden)

    Abdul Fatah

    2015-06-01

    Full Text Available Legal aid policy in the area carried out on several considerations including: Implementation of the authority given to the legal aid act, granting the guarantee and protection of access to justice and equality before the law in the area, equitable distribution of justice and increase public awareness and understanding of the law, and legal implications that accompanied the emergence of the right to legal counsel without pay and the right to choose the legal settlement. How To Cite Fatah, A. (2015. Regional Legal Assistance. Rechtsidee, 2(1, 1-10. doi:http://dx.doi.org/10.21070/jihr.v2i1.7

  13. Legal terminology in African languages | Alberts | Lexikos

    African Journals Online (AJOL)

    Various aspects regarding the present project (such as financing, time-schedule, training and terminological problems encountered) are treated. Keywords: legal terminology, sociolinguistic factors, terminology development, african languages, indigenous languages, multilingualism, subject fields, terminology, translation, ...

  14. Legal Education: Critical of Contemporaneity

    Directory of Open Access Journals (Sweden)

    Patrícia Verônica Nunes Carvalho Sobral

    2016-10-01

    Full Text Available This study reflects on the Legal Education, considering the criticism of contemporaneity. To reach the goal, the text is divided into: Critical, idealization and reality of legal education; Professor  of  law  schools;  The  educational  legislation  Questions  of  legal  education methodology; Pedagogy and the law. The reading of the sources referred the thought inferences  about  the  teaching  of  law,  the  methodological  approach  and  the  didactic- pedagogic preparation, according to Associação Latino Americana de Metodologia do Ensino do Direito. Contributes to the continuity of academic debate in progress, it is a problem that concerns the professional higher education.

  15. Refined isogeometric analysis for a preconditioned conjugate gradient solver

    KAUST Repository

    Garcia, Daniel; Pardo, D.; Dalcin, Lisandro; Calo, Victor M.

    2018-01-01

    Starting from a highly continuous Isogeometric Analysis (IGA) discretization, refined Isogeometric Analysis (rIGA) introduces C0 hyperplanes that act as separators for the direct LU factorization solver. As a result, the total computational cost

  16. Resolving Neighbourhood Relations in a Parallel Fluid Dynamic Solver

    KAUST Repository

    Frisch, Jerome; Mundani, Ralf-Peter; Rank, Ernst

    2012-01-01

    solver with a special aspect on the hierarchical data structure, unique cell and grid identification, and the neighbourhood relations in-between grids on different processes. A special server concept keeps track of every grid over all processes while

  17. Advanced Algebraic Multigrid Solvers for Subsurface Flow Simulation

    KAUST Repository

    Chen, Meng-Huo; Sun, Shuyu; Salama, Amgad

    2015-01-01

    and issues will be addressed and the corresponding remedies will be studied. As the multigrid methods are used as the linear solver, the simulator can be parallelized (although not trivial) and the high-resolution simulation become feasible, the ultimately

  18. A Family of High-Performance Solvers for Linear Model Predictive Control

    DEFF Research Database (Denmark)

    Frison, Gianluca; Sokoler, Leo Emil; Jørgensen, John Bagterp

    2014-01-01

    In Model Predictive Control (MPC), an optimization problem has to be solved at each sampling time, and this has traditionally limited the use of MPC to systems with slow dynamic. In this paper, we propose an e_cient solution strategy for the unconstrained sub-problems that give the search......-direction in Interior-Point (IP) methods for MPC, and that usually are the computational bottle-neck. This strategy combines a Riccati-like solver with the use of high-performance computing techniques: in particular, in this paper we explore the performance boost given by the use of single precision computation...

  19. Shared memory parallelism for 3D cartesian discrete ordinates solver

    International Nuclear Information System (INIS)

    Moustafa, S.; Dutka-Malen, I.; Plagne, L.; Poncot, A.; Ramet, P.

    2013-01-01

    This paper describes the design and the performance of DOMINO, a 3D Cartesian SN solver that implements two nested levels of parallelism (multi-core + SIMD - Single Instruction on Multiple Data) on shared memory computation nodes. DOMINO is written in C++, a multi-paradigm programming language that enables the use of powerful and generic parallel programming tools such as Intel TBB and Eigen. These two libraries allow us to combine multi-thread parallelism with vector operations in an efficient and yet portable way. As a result, DOMINO can exploit the full power of modern multi-core processors and is able to tackle very large simulations, that usually require large HPC clusters, using a single computing node. For example, DOMINO solves a 3D full core PWR eigenvalue problem involving 26 energy groups, 288 angular directions (S16), 46*10 6 spatial cells and 1*10 12 DoFs within 11 hours on a single 32-core SMP node. This represents a sustained performance of 235 GFlops and 40.74% of the SMP node peak performance for the DOMINO sweep implementation. The very high Flops/Watt ratio of DOMINO makes it a very interesting building block for a future many-nodes nuclear simulation tool. (authors)

  20. Development and acceleration of unstructured mesh-based cfd solver

    Science.gov (United States)

    Emelyanov, V.; Karpenko, A.; Volkov, K.

    2017-06-01

    The study was undertaken as part of a larger effort to establish a common computational fluid dynamics (CFD) code for simulation of internal and external flows and involves some basic validation studies. The governing equations are solved with ¦nite volume code on unstructured meshes. The computational procedure involves reconstruction of the solution in each control volume and extrapolation of the unknowns to find the flow variables on the faces of control volume, solution of Riemann problem for each face of the control volume, and evolution of the time step. The nonlinear CFD solver works in an explicit time-marching fashion, based on a three-step Runge-Kutta stepping procedure. Convergence to a steady state is accelerated by the use of geometric technique and by the application of Jacobi preconditioning for high-speed flows, with a separate low Mach number preconditioning method for use with low-speed flows. The CFD code is implemented on graphics processing units (GPUs). Speedup of solution on GPUs with respect to solution on central processing units (CPU) is compared with the use of different meshes and different methods of distribution of input data into blocks. The results obtained provide promising perspective for designing a GPU-based software framework for applications in CFD.

  1. A generalized Poisson solver for first-principles device simulations

    Energy Technology Data Exchange (ETDEWEB)

    Bani-Hashemian, Mohammad Hossein; VandeVondele, Joost, E-mail: joost.vandevondele@mat.ethz.ch [Nanoscale Simulations, ETH Zürich, 8093 Zürich (Switzerland); Brück, Sascha; Luisier, Mathieu [Integrated Systems Laboratory, ETH Zürich, 8092 Zürich (Switzerland)

    2016-01-28

    Electronic structure calculations of atomistic systems based on density functional theory involve solving the Poisson equation. In this paper, we present a plane-wave based algorithm for solving the generalized Poisson equation subject to periodic or homogeneous Neumann conditions on the boundaries of the simulation cell and Dirichlet type conditions imposed at arbitrary subdomains. In this way, source, drain, and gate voltages can be imposed across atomistic models of electronic devices. Dirichlet conditions are enforced as constraints in a variational framework giving rise to a saddle point problem. The resulting system of equations is then solved using a stationary iterative method in which the generalized Poisson operator is preconditioned with the standard Laplace operator. The solver can make use of any sufficiently smooth function modelling the dielectric constant, including density dependent dielectric continuum models. For all the boundary conditions, consistent derivatives are available and molecular dynamics simulations can be performed. The convergence behaviour of the scheme is investigated and its capabilities are demonstrated.

  2. Parallelizable approximate solvers for recursions arising in preconditioning

    Energy Technology Data Exchange (ETDEWEB)

    Shapira, Y. [Israel Inst. of Technology, Haifa (Israel)

    1996-12-31

    For the recursions used in the Modified Incomplete LU (MILU) preconditioner, namely, the incomplete decomposition, forward elimination and back substitution processes, a parallelizable approximate solver is presented. The present analysis shows that the solutions of the recursions depend only weakly on their initial conditions and may be interpreted to indicate that the inexact solution is close, in some sense, to the exact one. The method is based on a domain decomposition approach, suitable for parallel implementations with message passing architectures. It requires a fixed number of communication steps per preconditioned iteration, independently of the number of subdomains or the size of the problem. The overlapping subdomains are either cubes (suitable for mesh-connected arrays of processors) or constructed by the data-flow rule of the recursions (suitable for line-connected arrays with possibly SIMD or vector processors). Numerical examples show that, in both cases, the overhead in the number of iterations required for convergence of the preconditioned iteration is small relatively to the speed-up gained.

  3. A Python interface to Diffpack-based classes and solvers

    OpenAIRE

    Munthe-Kaas, Heidi Vikki

    2013-01-01

    Python is a programming language that has gained a lot of popularity during the last 15 years, and as a very easy-to-learn and flexible scripting language it is very well suited for computa- tional science, both in mathematics and in physics. Diffpack is a PDE library written in C++, made for easier implementation of both smaller PDE solvers and for larger libraries of simu- lators. It contains large class hierarchies for different solvers, grids, arrays, parallel computing and almost everyth...

  4. Legal aspects of intergenerational equity issues

    International Nuclear Information System (INIS)

    Green, H.P.

    1984-01-01

    This paper examines the extent to which American law and legal institutions have addressed problems of intergenerational equities. Beginning with a definition of the issue, the paper goes on to address conservation law, public debt ceilings, property law, and eugenic laws. The research supports the conclusion that neither statutory law, the formal expression of public policy articulated by the legislature, nor common law, the case-by-case definition of private legal rights by the courts has developed a coherent set of legal principles for dealing with the difficult problems of intergenerational equity. 15 references

  5. An a(α)-stable variable order ODE-solver and its application as advancement procedure for simulations in thermo- and fluid-dynamics

    International Nuclear Information System (INIS)

    Hofer, E.

    1981-01-01

    Simulations in thermo- and fluiddynamics often require the numerical solution of large initial value problems with stiffness caused by eigenvalues close to the imaginary axis. The regions of absolute stability of the most widely used ordinary differential equation (ODE) solvers, for stiff problems, do not properly account for this. The paper introduces a general purpose ODE-solver with considerably larger stability regions. Its reliability is illustrated by test problems, with complex eigenvalues, from a well known test package. Applications in large codes, for simulations in thermo- and fluiddynamics, demonstrate its practical usability. (orig.) [de

  6. The Legal Regime of Nuclear Power Satellites-A Problem at the Cross-Roads of Nuclear Law and Space Law

    International Nuclear Information System (INIS)

    Courteix, S.

    1992-01-01

    The number of nuclear-powered satellites rises constantly and, recalling the fear generated by the crash of the Cosmos 954 satellite, the author points out that radioactive debris falling on earth could represent as great a hazard as accidental releases of radioactive material from land-based nuclear installations. Such satellites, therefore, can be governed by both space law and nuclear law. On the basis of international conventions applicable in the two fields and also with reference to the Law of the Sea and environmental law, the article analyses preventive and radiation protection measures as well as emergency plans and also raises the problem of liability and compensation for damage. (NEA)

  7. Laws of Language and Legal Language: A Study of Legal Language in Some Indonesian Regulations

    Directory of Open Access Journals (Sweden)

    Shidarta Shidarta

    2017-01-01

    Full Text Available Legal language must follow the laws of language (grammar that widely known and commonly used by the public, including groups of the scientist. Legal language on the other hand also recognizes specific terminologies. These terminologies were introduced by jurists or by legislative power holders. Accordingly, legal language became the product of legal doctrines or political decisions. The problems arose when a number of compositions and legal terms turned out to be elusive, convoluted, and ambiguous due to the pattern of writing that was once done and because of certain considerations. This article proposed reviewing the factors that result in problems. The author presented a solution to observe using hermeneutic methods of law and legal reasoning. The author argued that the text of the law was not neutral since it was trapped not only by the laws of language but also by the perspective of the interpreters as they believed such a perspective was based on the guidance of legal science. By using legal hermeneutics can be checked the depth of the meaning of the law; while over the legal reasoning can be seen its rationale according to legal science.

  8. Preliminary applications of the new Neptune two-phase CFD solver to pressurized thermal shock investigations

    International Nuclear Information System (INIS)

    Boucker, M.; Laviaville, J.; Martin, A.; Bechaud, C.; Bestion, D.; Coste, P.

    2004-01-01

    The objective of this communication is to present some preliminary applications to pressurized thermal shock (PTS) investigations of the CFD (Computational Fluid Dynamics) two-phase flow solver of the new NEPTUNE thermal-hydraulics platform. In the framework of plant life extension, the Reactor Pressure Vessel (RPV) integrity is a major concern, and an important part of RPV integrity assessment is related to PTS analysis. In the case where the cold legs are partially filled with steam, it becomes a two-phase problem and new important effects occur, such as condensation due to the Emergency Core Cooling (ECC) injections of sub-cooled water. Thus, an advanced prediction of RPV thermal loading during these transients requires sophisticated two-phase, local scale, 3-dimensional codes. In that purpose, a program has been set up to extend the capabilities of the NEPTUNE two-phase CFD solver. A simple set of turbulence and condensation model for free surface steam-water flow has been tested in simulation of an ECC high pressure injection representing facility, using a full 3-dimensional mesh and the new NEPTUNE solver. Encouraging results have been obtained but it should be noticed that several sources of error can compensate for one another. Nevertheless, the computation presented here allows to be reasonable confident in the use of two-phase CFD in order to carry out refined analysis of two-phase PTS scenarios within the next years

  9. Dementia and Legal Competency

    OpenAIRE

    Filaković, Pavo; Petek Erić, Anamarija; Mihanović, Mate; Glavina, Trpimir; Molnar, Sven

    2011-01-01

    The legal competency or capability to exercise rights is level of judgment and decision-making ability needed to manage one's own affairs and to sign official documents. With some exceptions, the person entitles this right in age of majority. It is acquired without legal procedures, however the annulment of legal capacity requires a juristic process. This resolution may not be final and could be revoked thorough the procedure of reverting legal capacity – fully or partially. Given ...

  10. 32 CFR 727.6 - Functions of legal assistance officers.

    Science.gov (United States)

    2010-07-01

    ... another party or his lawyer, and prepare all types of legal documents, including pleadings, as are... Act of 1964 and pertinent Navy instructions. (b) Nature of assistance. Legal assistance officers and... problems, business ventures, or matters that are not of a personal nature. Legal assistance duties are...

  11. The Legal Case

    NARCIS (Netherlands)

    Sartor, Giovanni; Contissa, Giuseppe; Schebesta, H.; Laukyte, Migle; Lanzi, Paola; Marti, Patrizia; Paola, Tomasello

    2013-01-01

    This paper presents the first release of the Legal Case, recently developed by the ALIAS Project and still under refinement. The Legal Case is a methodological tool intended to address liability issues of automated ATM systems: it provides for a legal risk management process that can be applied

  12. The Legal Ethical Backbone of Conscientious Refusal.

    Science.gov (United States)

    Munthe, Christian; Nielsen, Morten Ebbe Juul

    2017-01-01

    This article analyzes the idea of a legal right to conscientious refusal for healthcare professionals from a basic legal ethical standpoint, using refusal to perform tasks related to legal abortion (in cases of voluntary employment) as a case in point. The idea of a legal right to conscientious refusal is distinguished from ideas regarding moral rights or reasons related to conscientious refusal, and none of the latter are found to support the notion of a legal right. Reasons for allowing some sort of room for conscientious refusal for healthcare professionals based on the importance of cultural identity and the fostering of a critical atmosphere might provide some support, if no countervailing factors apply. One such factor is that a legal right to healthcare professionals' conscientious refusal must comply with basic legal ethical tenets regarding the rule of law and equal treatment, and this requirement is found to create serious problems for those wishing to defend the idea under consideration. We conclude that the notion of a legal right to conscientious refusal for any profession is either fundamentally incompatible with elementary legal ethical requirements, or implausible because it undermines the functioning of a related professional sector (healthcare) or even of society as a whole.

  13. The Legal Regulation of Cybersecurity

    Directory of Open Access Journals (Sweden)

    Darius Štitilis

    2013-08-01

    Full Text Available Cybercrime has become a global phenomenon, which is causing more harm to individual citizens, organizations, society and the state. Most countries in the world compare cybercrime with offences such as terrorism and drug trafficking due to its risks and profitability. Cybersecurity is the central category to fight cybercrime in cyberspace. Therefore, the strategic legal regulation of cybersecurity is one of the most relevant problems in EU, including Lithuania. So far cybersecurity legal regulation analysis in scientific literature has been rather limited. The European Commission, together with the High Representative of the Union for Foreign Affairs and Security Policy, has published a cybersecurity strategy alongside a Commission proposed directive on network and information security (NIS. The cybersecurity strategy – “An Open, Safe and Secure Cyberspace” - represents the EU’s comprehensive vision on how best to prevent and respond to cyber disruptions and attacks. The purpose of its is to further European values of freedom and democracy and ensure the digital economy can safely grow. Specific actions are aimed at enhancing cyber resilience of information systems, reducing cybercrime and strengthening EU international cyber-security policy and cyber defence. The main goal of the paper is to analyze and compare the EU cybersecurity strategy and experience of several foreign countries with the strategic legal regulation of cybersecurity in Lithuania. The article consists of four parts. The first part dealt with the EU cybersecurity strategy. The second part of the article examines the comparative aspect of foreign cybersecurity strategic legal regulation. The third part deals with attempts in Lithuania to draft cybersecurity law and the holistic approach of cybersecurity legal regulation. The fourth part examines Lithuanian cybersecurity strategy and comments on the main probleas related with the strategy. Several different approaches

  14. Towards enhanced public access to legal information : A proposal for official networked one-stop legal information websites

    NARCIS (Netherlands)

    Mitee, Leesi Ebenezer

    2018-01-01

    Abstract: This article identifies the publishing of fragments of legal information on multiple, isolated official legal information websites (OLIWs) as the major factor underlying the existing problems in locating the available official online legal information of all levels of government (national,

  15. Continuous-time quantum Monte Carlo impurity solvers

    Science.gov (United States)

    Gull, Emanuel; Werner, Philipp; Fuchs, Sebastian; Surer, Brigitte; Pruschke, Thomas; Troyer, Matthias

    2011-04-01

    Continuous-time quantum Monte Carlo impurity solvers are algorithms that sample the partition function of an impurity model using diagrammatic Monte Carlo techniques. The present paper describes codes that implement the interaction expansion algorithm originally developed by Rubtsov, Savkin, and Lichtenstein, as well as the hybridization expansion method developed by Werner, Millis, Troyer, et al. These impurity solvers are part of the ALPS-DMFT application package and are accompanied by an implementation of dynamical mean-field self-consistency equations for (single orbital single site) dynamical mean-field problems with arbitrary densities of states. Program summaryProgram title: dmft Catalogue identifier: AEIL_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIL_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: ALPS LIBRARY LICENSE version 1.1 No. of lines in distributed program, including test data, etc.: 899 806 No. of bytes in distributed program, including test data, etc.: 32 153 916 Distribution format: tar.gz Programming language: C++ Operating system: The ALPS libraries have been tested on the following platforms and compilers: Linux with GNU Compiler Collection (g++ version 3.1 and higher), and Intel C++ Compiler (icc version 7.0 and higher) MacOS X with GNU Compiler (g++ Apple-version 3.1, 3.3 and 4.0) IBM AIX with Visual Age C++ (xlC version 6.0) and GNU (g++ version 3.1 and higher) compilers Compaq Tru64 UNIX with Compq C++ Compiler (cxx) SGI IRIX with MIPSpro C++ Compiler (CC) HP-UX with HP C++ Compiler (aCC) Windows with Cygwin or coLinux platforms and GNU Compiler Collection (g++ version 3.1 and higher) RAM: 10 MB-1 GB Classification: 7.3 External routines: ALPS [1], BLAS/LAPACK, HDF5 Nature of problem: (See [2].) Quantum impurity models describe an atom or molecule embedded in a host material with which it can exchange electrons. They are basic to nanoscience as

  16. A high performance dual revised simplex solver

    OpenAIRE

    Hall, Julian; Huangfu, Qi

    2012-01-01

    When solving families of related linear programming (LP) problems and many classes of single LP problems, the simplex method is the preferred computational technique. Hitherto there has been no efficient parallel implementation of the simplex method that gives good speed-up on general, large sparse LP problems. This paper presents a variant of the dual simplex method and a prototype parallelisation scheme. The resulting implementation, ParISS, is efficient when run in serial and offers modest...

  17. Practical Problems of Legal Regulation of Customs Duties Developing an International Trade Between the Republic of Lithuania And East Asian Countries

    Directory of Open Access Journals (Sweden)

    Valantiejus Gediminas

    2016-12-01

    Full Text Available For more than ten years (since 2004 the Republic of Lithuania is a member of the EU and is realizing its economic and trade relations with other foreign countries, and regulating customs duties according to the requirements of the EU Common Commercial Policy. However, in the recent years foreign trade (in particular - exports of goods remained one of the main factors which increased an economic growth (recovery in the Republic of Lithuania after the global economic crisis of the world, which began in 2008. In this context, the search for new markets and expansion of trade relations with new trade partners in Asia became essential in order to diversify the structure of the national economy and avoid dependence on traditional trade partners, such as Russia. Taking into account this strategic goal, the article seeks to answer a question whether an existing foreign trade regulation system ensures the status of Lithuania as an attractive partner of foreign trade with East Asian countries (Taiwan, Hong Kong, South Korea and Singapore and what regulatory instruments (customs duty rules and procedures should be used on the national level to ensure cooperation with these countries. In order to answer this problematic question, the first chapter of the article overviews general tendencies in Lithuanian foreign trade with the countries of East Asia, while the second chapter is dedicated to describe regulatory regime for import customs duties on the national level (in line with the major provisions of the EU Common Commercial Policy. The practical problems and obstacles to international trade are presented in the third chapter and are illustrated by the examples of case law, which was formed in disputes relating to the decisions and actions of Lithuanian national customs authorities for the period from 1 May, 2004 (since entry to the EU.

  18. BCYCLIC: A parallel block tridiagonal matrix cyclic solver

    Science.gov (United States)

    Hirshman, S. P.; Perumalla, K. S.; Lynch, V. E.; Sanchez, R.

    2010-09-01

    A block tridiagonal matrix is factored with minimal fill-in using a cyclic reduction algorithm that is easily parallelized. Storage of the factored blocks allows the application of the inverse to multiple right-hand sides which may not be known at factorization time. Scalability with the number of block rows is achieved with cyclic reduction, while scalability with the block size is achieved using multithreaded routines (OpenMP, GotoBLAS) for block matrix manipulation. This dual scalability is a noteworthy feature of this new solver, as well as its ability to efficiently handle arbitrary (non-powers-of-2) block row and processor numbers. Comparison with a state-of-the art parallel sparse solver is presented. It is expected that this new solver will allow many physical applications to optimally use the parallel resources on current supercomputers. Example usage of the solver in magneto-hydrodynamic (MHD), three-dimensional equilibrium solvers for high-temperature fusion plasmas is cited.

  19. MINOS: A simplified Pn solver for core calculation

    International Nuclear Information System (INIS)

    Baudron, A.M.; Lautard, J.J.

    2007-01-01

    This paper describes a new generation of the neutronic core solver MINOS resulting from developments done in the DESCARTES project. For performance reasons, the numerical method of the existing MINOS solver in the SAPHYR system has been reused in the new system. It is based on the mixed-dual finite element approximation of the simplified transport equation. We have extended the previous method to the treatment of unstructured geometries composed by quadrilaterals, allowing us to treat geometries where fuel pins are exactly represented. For Cartesian geometries, the solver takes into account assembly discontinuity coefficients in the simplified P n context. The solver has been rewritten in C + + programming language using an object-oriented design. Its general architecture was reconsidered in order to improve its capability of evolution and its maintainability. Moreover, the performance of the previous version has been improved mainly regarding the matrix construction time; this result improves significantly the performance of the solver in the context of industrial application requiring thermal-hydraulic feedback and depletion calculations. (authors)

  20. Dementia and legal competency.

    Science.gov (United States)

    Filaković, Pavo; Erić, Anamarija Petek; Mihanović, Mate; Glavina, Trpimir; Molnar, Sven

    2011-06-01

    The legal competency or capability to exercise rights is level of judgment and decision-making ability needed to manage one's own affairs and to sign official documents. With some exceptions, the person entitles this right in age of majority. It is acquired without legal procedures, however the annulment of legal capacity requires a juristic process. This resolution may not be final and could be revoked thorough the procedure of reverting legal capacity - fully or partially. Given the increasing number of persons with dementia, they are often subjects of legal expertise concerning their legal capacity. On the other part, emphasis on the civil rights of mentally ill also demands their maximal protection. Therefore such distinctive issue is approached with particular attention. The approach in determination of legal competency is more focused on gradation of it's particular aspects instead of existing dual concept: legally capable - legally incapable. The main assumption represents how person with dementia is legally capable and should enjoy all the rights, privileges and obligations as other citizens do. The aspects of legal competency for which person with dementia is going to be deprived, due to protection of one's rights and interests, are determined in legal procedure and then passed over to the guardian decided by court. Partial annulment of legal competency is measure applied when there is even one existing aspect of preserved legal capability (pension disposition, salary or pension disposition, ability of concluding contract, making testament, concluding marriage, divorce, choosing whereabouts, independent living, right to vote, right to decide course of treatment ect.). This measure is most often in favour of the patient and rarely for protection of other persons and their interests. Physicians are expected to precisely describe early dementia symptoms which may influence assessment of specific aspects involved in legal capacity (memory loss, impaired task

  1. The analytic nodal diffusion solver ANDES in multigroups for 3D rectangular geometry: Development and performance analysis

    International Nuclear Information System (INIS)

    Lozano, Juan-Andres; Garcia-Herranz, Nuria; Ahnert, Carol; Aragones, Jose-Maria

    2008-01-01

    In this work we address the development and implementation of the analytic coarse-mesh finite-difference (ACMFD) method in a nodal neutron diffusion solver called ANDES. The first version of the solver is implemented in any number of neutron energy groups, and in 3D Cartesian geometries; thus it mainly addresses PWR and BWR core simulations. The details about the generalization to multigroups and 3D, as well as the implementation of the method are given. The transverse integration procedure is the scheme chosen to extend the ACMFD formulation to multidimensional problems. The role of the transverse leakage treatment in the accuracy of the nodal solutions is analyzed in detail: the involved assumptions, the limitations of the method in terms of nodal width, the alternative approaches to implement the transverse leakage terms in nodal methods - implicit or explicit -, and the error assessment due to transverse integration. A new approach for solving the control rod 'cusping' problem, based on the direct application of the ACMFD method, is also developed and implemented in ANDES. The solver architecture turns ANDES into an user-friendly, modular and easily linkable tool, as required to be integrated into common software platforms for multi-scale and multi-physics simulations. ANDES can be used either as a stand-alone nodal code or as a solver to accelerate the convergence of whole core pin-by-pin code systems. The verification and performance of the solver are demonstrated using both proof-of-principle test cases and well-referenced international benchmarks

  2. Final Report for 'Implimentation and Evaluation of Multigrid Linear Solvers into Extended Magnetohydrodynamic Codes for Petascale Computing'

    International Nuclear Information System (INIS)

    Vadlamani, Srinath; Kruger, Scott; Austin, Travis

    2008-01-01

    Extended magnetohydrodynamic (MHD) codes are used to model the large, slow-growing instabilities that are projected to limit the performance of International Thermonuclear Experimental Reactor (ITER). The multiscale nature of the extended MHD equations requires an implicit approach. The current linear solvers needed for the implicit algorithm scale poorly because the resultant matrices are so ill-conditioned. A new solver is needed, especially one that scales to the petascale. The most successful scalable parallel processor solvers to date are multigrid solvers. Applying multigrid techniques to a set of equations whose fundamental modes are dispersive waves is a promising solution to CEMM problems. For the Phase 1, we implemented multigrid preconditioners from the HYPRE project of the Center for Applied Scientific Computing at LLNL via PETSc of the DOE SciDAC TOPS for the real matrix systems of the extended MHD code NIMROD which is a one of the primary modeling codes of the OFES-funded Center for Extended Magnetohydrodynamic Modeling (CEMM) SciDAC. We implemented the multigrid solvers on the fusion test problem that allows for real matrix systems with success, and in the process learned about the details of NIMROD data structures and the difficulties of inverting NIMROD operators. The further success of this project will allow for efficient usage of future petascale computers at the National Leadership Facilities: Oak Ridge National Laboratory, Argonne National Laboratory, and National Energy Research Scientific Computing Center. The project will be a collaborative effort between computational plasma physicists and applied mathematicians at Tech-X Corporation, applied mathematicians Front Range Scientific Computations, Inc. (who are collaborators on the HYPRE project), and other computational plasma physicists involved with the CEMM project.

  3. Hybrid Direct and Iterative Solver with Library of Multi-criteria Optimal Orderings for h Adaptive Finite Element Method Computations

    KAUST Repository

    AbouEisha, Hassan M.

    2016-06-02

    In this paper we present a multi-criteria optimization of element partition trees and resulting orderings for multi-frontal solver algorithms executed for two dimensional h adaptive finite element method. In particular, the problem of optimal ordering of elimination of rows in the sparse matrices resulting from adaptive finite element method computations is reduced to the problem of finding of optimal element partition trees. Given a two dimensional h refined mesh, we find all optimal element partition trees by using the dynamic programming approach. An element partition tree defines a prescribed order of elimination of degrees of freedom over the mesh. We utilize three different metrics to estimate the quality of the element partition tree. As the first criterion we consider the number of floating point operations(FLOPs) performed by the multi-frontal solver. As the second criterion we consider the number of memory transfers (MEMOPS) performed by the multi-frontal solver algorithm. As the third criterion we consider memory usage (NONZEROS) of the multi-frontal direct solver. We show the optimization results for FLOPs vs MEMOPS as well as for the execution time estimated as FLOPs+100MEMOPS vs NONZEROS. We obtain Pareto fronts with multiple optimal trees, for each mesh, and for each refinement level. We generate a library of optimal elimination trees for small grids with local singularities. We also propose an algorithm that for a given large mesh with identified local sub-grids, each one with local singularity. We compute Schur complements over the sub-grids using the optimal trees from the library, and we submit the sequence of Schur complements into the iterative solver ILUPCG.

  4. An h-adaptive finite element solver for the calculations of the electronic structures

    International Nuclear Information System (INIS)

    Bao Gang; Hu Guanghui; Liu Di

    2012-01-01

    In this paper, a framework of using h-adaptive finite element method for the Kohn–Sham equation on the tetrahedron mesh is presented. The Kohn–Sham equation is discretized by the finite element method, and the h-adaptive technique is adopted to optimize the accuracy and the efficiency of the algorithm. The locally optimal block preconditioned conjugate gradient method is employed for solving the generalized eigenvalue problem, and an algebraic multigrid preconditioner is used to accelerate the solver. A variety of numerical experiments demonstrate the effectiveness of our algorithm for both the all-electron and the pseudo-potential calculations.

  5. Multilevel solvers of first-order system least-squares for Stokes equations

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Chen-Yao G. [National Chung Cheng Univ., Chia-Yi (Taiwan, Province of China)

    1996-12-31

    Recently, The use of first-order system least squares principle for the approximate solution of Stokes problems has been extensively studied by Cai, Manteuffel, and McCormick. In this paper, we study multilevel solvers of first-order system least-squares method for the generalized Stokes equations based on the velocity-vorticity-pressure formulation in three dimensions. The least-squares functionals is defined to be the sum of the L{sup 2}-norms of the residuals, which is weighted appropriately by the Reynolds number. We develop convergence analysis for additive and multiplicative multilevel methods applied to the resulting discrete equations.

  6. Description and use of LSODE, the Livermore Solver for Ordinary Differential Equations

    Science.gov (United States)

    Radhakrishnan, Krishnan; Hindmarsh, Alan C.

    1993-01-01

    LSODE, the Livermore Solver for Ordinary Differential Equations, is a package of FORTRAN subroutines designed for the numerical solution of the initial value problem for a system of ordinary differential equations. It is particularly well suited for 'stiff' differential systems, for which the backward differentiation formula method of orders 1 to 5 is provided. The code includes the Adams-Moulton method of orders 1 to 12, so it can be used for nonstiff problems as well. In addition, the user can easily switch methods to increase computational efficiency for problems that change character. For both methods a variety of corrector iteration techniques is included in the code. Also, to minimize computational work, both the step size and method order are varied dynamically. This report presents complete descriptions of the code and integration methods, including their implementation. It also provides a detailed guide to the use of the code, as well as an illustrative example problem.

  7. Control of error and convergence in ODE solvers

    International Nuclear Information System (INIS)

    Gustafsson, K.

    1992-03-01

    Feedback is a general principle that can be used in many different contexts. In this thesis it is applied to numerical integration of ordinary differential equations. An advanced integration method includes parameters and variables that should be adjusted during the execution. In addition, the integration method should be able to automatically handle situations such as: initialization, restart after failures, etc. In this thesis we regard the algorithms for parameter adjustment and supervision as a controller. The controlled measures different variable that tell the current status of the integration, and based on this information it decides how to continue. The design of the controller is vital in order to accurately and efficiently solve a large class of ordinary differential equations. The application of feedback control may appear farfetched, but numerical integration methods are in fact dynamical systems. This is often overlooked in traditional numerical analysis. We derive dynamic models that describe the behavior of the integration method as well as the standard control algorithms in use today. Using these models it is possible to analyze properties of current algorithms, and also explain some generally observed misbehaviors. Further, we use the acquired insight to derive new and improved control algorithms, both for explicit and implicit Runge-Kutta methods. In the explicit case, the new controller gives good overall performance. In particular it overcomes the problem with oscillating stepsize sequence that is often experienced when the stepsize is restricted by numerical stability. The controller for implicit methods is designed so that it tracks changes in the differential equation better than current algorithms. In addition, it includes a new strategy for the equation solver, which allows the stepsize to vary more freely. This leads to smoother error control without excessive operations on the iteration matrix. (87 refs.) (au)

  8. Legal method in danish law

    DEFF Research Database (Denmark)

    Blume, Peter Erik

    and furthermore a brief account of Danish legal history is provided. The following chapters concern: • Legal institutions, • Statute and Statutory Law • Legal Decisions • Legal Literature and Legal Knowledge • Other National Legal Sources • External Influences on Danish Law......This book describes how legal method is used within the Danish legal system. Its target group is foreign lawyers and law students who have an interest in knowing how Danish law commonly is determined and applied. In the first chapters legal method and legal sources in general are defined...

  9. Legal issues of tax rates

    OpenAIRE

    Sadílek, Jiří

    2010-01-01

    Tax rate problems The subject of the graduation thesis is legal problems of tax rate. The aim of this thesis is description and estimation of the flat tax rate and states, where is established. First of all I define the basic kinds of tax systems - the tax system with one tax rate, the progressive tax system and the flat tax system. Further I deal with the principles and elements of the flat tax rate as interpreted by American economists Robert E. Hall and Alvin Rabushka who are generally ack...

  10. Energy consumption optimization of the total-FETI solver by changing the CPU frequency

    Science.gov (United States)

    Horak, David; Riha, Lubomir; Sojka, Radim; Kruzik, Jakub; Beseda, Martin; Cermak, Martin; Schuchart, Joseph

    2017-07-01

    The energy consumption of supercomputers is one of the critical problems for the upcoming Exascale supercomputing era. The awareness of power and energy consumption is required on both software and hardware side. This paper deals with the energy consumption evaluation of the Finite Element Tearing and Interconnect (FETI) based solvers of linear systems, which is an established method for solving real-world engineering problems. We have evaluated the effect of the CPU frequency on the energy consumption of the FETI solver using a linear elasticity 3D cube synthetic benchmark. In this problem, we have evaluated the effect of frequency tuning on the energy consumption of the essential processing kernels of the FETI method. The paper provides results for two types of frequency tuning: (1) static tuning and (2) dynamic tuning. For static tuning experiments, the frequency is set before execution and kept constant during the runtime. For dynamic tuning, the frequency is changed during the program execution to adapt the system to the actual needs of the application. The paper shows that static tuning brings up 12% energy savings when compared to default CPU settings (the highest clock rate). The dynamic tuning improves this further by up to 3%.

  11. Medico legal issues.

    Science.gov (United States)

    Mackenzie, Geraldine; Carter, Hugh

    2010-01-01

    This chapter gives an educational overview of: * An awareness of the legal issues involved in health informatics * The need for the privacy and security of the patient record * The legal consequences of a breach of the security of the patient record * The concept of privacy law and what precautions ought to be taken to minimize legal liability for a breach of privacy and/or confidentiality.

  12. Legal questions concerning the licensing procedure of nuclear power plants

    International Nuclear Information System (INIS)

    Boerner, B.

    1978-01-01

    The publication contains 4 articles which deal with legal practice and problems of the licensing procedure in the Federal Republic of Germany: 1) Actions brought by joint boards from the constitutional point of view (Burmeister, J.); 2) court review of the assessment of technical and economic questions concerning the licensing of power plant construction (Ossenbuehl, F.); 3) the site plan approval procedure as a legal problem (Friauf, K.H.); 4) legal questions concerning the immediate enforceability (Papier, H.J.). (HP) [de

  13. On Cafesat: A Modern SAT Solver for Scala

    OpenAIRE

    Blanc, Régis William

    2013-01-01

    We present CafeSat, a SAT solver written in the Scala programming language. CafeSat is a modern solver based on DPLL and featuring many state-of-the-art techniques and heuristics. It uses two-watched literals for Boolean constraint propagation, conflict-driven learning along with clause deletion, a restarting strategy, and the VSIDS heuristics for choosing the branching literal. CafeSat is both sound and complete. In order to achieve reasonnable performances, low level and hand-tuned data ...

  14. MINARET: Towards a time-dependent neutron transport parallel solver

    International Nuclear Information System (INIS)

    Baudron, A.M.; Lautard, J.J.; Maday, Y.; Mula, O.

    2013-01-01

    We present the newly developed time-dependent 3D multigroup discrete ordinates neutron transport solver that has recently been implemented in the MINARET code. The solver is the support for a study about computing acceleration techniques that involve parallel architectures. In this work, we will focus on the parallelization of two of the variables involved in our equation: the angular directions and the time. This last variable has been parallelized by a (time) domain decomposition method called the para-real in time algorithm. (authors)

  15. Development of legal environment for Rosatom Corporation

    International Nuclear Information System (INIS)

    El'fimova, T.L.

    2012-01-01

    The scope of legal and regulatory work within the Corporation Rosatom is characterized with the large number of legal acts that have been developed and adopted under the initiative of the Corporation Rosatom that aim to address objectives associated with the advancement of the nuclear energy of Russia. The rapidly expanding industry requires their continuous development and improvement. The tasks and problems of legislation pertaining to use of nuclear energy and safety regulation are discussed in the paper [ru

  16. Computational cost of isogeometric multi-frontal solvers on parallel distributed memory machines

    KAUST Repository

    Woźniak, Maciej

    2015-02-01

    This paper derives theoretical estimates of the computational cost for isogeometric multi-frontal direct solver executed on parallel distributed memory machines. We show theoretically that for the Cp-1 global continuity of the isogeometric solution, both the computational cost and the communication cost of a direct solver are of order O(log(N)p2) for the one dimensional (1D) case, O(Np2) for the two dimensional (2D) case, and O(N4/3p2) for the three dimensional (3D) case, where N is the number of degrees of freedom and p is the polynomial order of the B-spline basis functions. The theoretical estimates are verified by numerical experiments performed with three parallel multi-frontal direct solvers: MUMPS, PaStiX and SuperLU, available through PETIGA toolkit built on top of PETSc. Numerical results confirm these theoretical estimates both in terms of p and N. For a given problem size, the strong efficiency rapidly decreases as the number of processors increases, becoming about 20% for 256 processors for a 3D example with 1283 unknowns and linear B-splines with C0 global continuity, and 15% for a 3D example with 643 unknowns and quartic B-splines with C3 global continuity. At the same time, one cannot arbitrarily increase the problem size, since the memory required by higher order continuity spaces is large, quickly consuming all the available memory resources even in the parallel distributed memory version. Numerical results also suggest that the use of distributed parallel machines is highly beneficial when solving higher order continuity spaces, although the number of processors that one can efficiently employ is somehow limited.

  17. Acceleration of the OpenFOAM-based MHD solver using graphics processing units

    International Nuclear Information System (INIS)

    He, Qingyun; Chen, Hongli; Feng, Jingchao

    2015-01-01

    Highlights: • A 3D PISO-MHD was implemented on Kepler-class graphics processing units (GPUs) using CUDA technology. • A consistent and conservative scheme is used in the code which was validated by three basic benchmarks in a rectangular and round ducts. • Parallelized of CPU and GPU acceleration were compared relating to single core CPU in MHD problems and non-MHD problems. • Different preconditions for solving MHD solver were compared and the results showed that AMG method is better for calculations. - Abstract: The pressure-implicit with splitting of operators (PISO) magnetohydrodynamics MHD solver of the couple of Navier–Stokes equations and Maxwell equations was implemented on Kepler-class graphics processing units (GPUs) using the CUDA technology. The solver is developed on open source code OpenFOAM based on consistent and conservative scheme which is suitable for simulating MHD flow under strong magnetic field in fusion liquid metal blanket with structured or unstructured mesh. We verified the validity of the implementation on several standard cases including the benchmark I of Shercliff and Hunt's cases, benchmark II of fully developed circular pipe MHD flow cases and benchmark III of KIT experimental case. Computational performance of the GPU implementation was examined by comparing its double precision run times with those of essentially the same algorithms and meshes. The resulted showed that a GPU (GTX 770) can outperform a server-class 4-core, 8-thread CPU (Intel Core i7-4770k) by a factor of 2 at least.

  18. Acceleration of the OpenFOAM-based MHD solver using graphics processing units

    Energy Technology Data Exchange (ETDEWEB)

    He, Qingyun; Chen, Hongli, E-mail: hlchen1@ustc.edu.cn; Feng, Jingchao

    2015-12-15

    Highlights: • A 3D PISO-MHD was implemented on Kepler-class graphics processing units (GPUs) using CUDA technology. • A consistent and conservative scheme is used in the code which was validated by three basic benchmarks in a rectangular and round ducts. • Parallelized of CPU and GPU acceleration were compared relating to single core CPU in MHD problems and non-MHD problems. • Different preconditions for solving MHD solver were compared and the results showed that AMG method is better for calculations. - Abstract: The pressure-implicit with splitting of operators (PISO) magnetohydrodynamics MHD solver of the couple of Navier–Stokes equations and Maxwell equations was implemented on Kepler-class graphics processing units (GPUs) using the CUDA technology. The solver is developed on open source code OpenFOAM based on consistent and conservative scheme which is suitable for simulating MHD flow under strong magnetic field in fusion liquid metal blanket with structured or unstructured mesh. We verified the validity of the implementation on several standard cases including the benchmark I of Shercliff and Hunt's cases, benchmark II of fully developed circular pipe MHD flow cases and benchmark III of KIT experimental case. Computational performance of the GPU implementation was examined by comparing its double precision run times with those of essentially the same algorithms and meshes. The resulted showed that a GPU (GTX 770) can outperform a server-class 4-core, 8-thread CPU (Intel Core i7-4770k) by a factor of 2 at least.

  19. Scalable multi-grid preconditioning techniques for the even-parity S_N solver in UNIC

    International Nuclear Information System (INIS)

    Mahadevan, Vijay S.; Smith, Michael A.

    2011-01-01

    The Even-parity neutron transport equation with FE-S_N discretization is solved traditionally using SOR preconditioned CG method at the lowest level of iterations in order to compute the criticality in reactor analysis problems. The use of high order isoparametric finite elements prohibits the formation of the discrete operator explicitly due to memory constraints in peta scale architectures. Hence, a h-p multi-grid preconditioner based on linear tessellation of the higher order mesh is introduced here for the space-angle system and compared against SOR and Algebraic MG black-box solvers. The performance and scalability of the multi-grid scheme was determined for two test problems and found to be competitive in terms of both computational time and memory requirements. The implementation of this preconditioner in an even-parity solver like UNIC from ANL can further enable high fidelity calculations in a scalable manner on peta flop machines. (author)

  20. A legal approach to radioactive waste management

    International Nuclear Information System (INIS)

    Derche, B.; Rocamora, P.; Salelles, A.

    1983-01-01

    The authors of this paper review the major legal problems raised by radioactive waste management. They stress the complexity of such problems by posing three main queries: surveillance or no surveillance; liability or no liability and finally internationalisation or national jurisdiction. This analysis seeks to provide food for thought on each point rather than a solution to the questions reviewed. (NEA) [fr

  1. A parallel solver for huge dense linear systems

    Science.gov (United States)

    Badia, J. M.; Movilla, J. L.; Climente, J. I.; Castillo, M.; Marqués, M.; Mayo, R.; Quintana-Ortí, E. S.; Planelles, J.

    2011-11-01

    HDSS (Huge Dense Linear System Solver) is a Fortran Application Programming Interface (API) to facilitate the parallel solution of very large dense systems to scientists and engineers. The API makes use of parallelism to yield an efficient solution of the systems on a wide range of parallel platforms, from clusters of processors to massively parallel multiprocessors. It exploits out-of-core strategies to leverage the secondary memory in order to solve huge linear systems O(100.000). The API is based on the parallel linear algebra library PLAPACK, and on its Out-Of-Core (OOC) extension POOCLAPACK. Both PLAPACK and POOCLAPACK use the Message Passing Interface (MPI) as the communication layer and BLAS to perform the local matrix operations. The API provides a friendly interface to the users, hiding almost all the technical aspects related to the parallel execution of the code and the use of the secondary memory to solve the systems. In particular, the API can automatically select the best way to store and solve the systems, depending of the dimension of the system, the number of processes and the main memory of the platform. Experimental results on several parallel platforms report high performance, reaching more than 1 TFLOP with 64 cores to solve a system with more than 200 000 equations and more than 10 000 right-hand side vectors. New version program summaryProgram title: Huge Dense System Solver (HDSS) Catalogue identifier: AEHU_v1_1 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHU_v1_1.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 87 062 No. of bytes in distributed program, including test data, etc.: 1 069 110 Distribution format: tar.gz Programming language: Fortran90, C Computer: Parallel architectures: multiprocessors, computer clusters Operating system

  2. Agency Problems, Legal Strategies, and Enforcement

    OpenAIRE

    Kraakman, Reinier H.; Armour, John; Hansmann, Henry

    2009-01-01

    This article is the second chapter of the second edition of "The Anatomy of Corporate Law: A Comparative and Functional Approach," by Reinier Kraakman, John Armour, Paul Davies, Luca Enriques, Henry Hansmann, Gerard Hertig, Klaus Hopt, Hideki Kanda and Edward Rock (Oxford University Press 2009). The book as a whole provides a functional analysis of corporate (or company) law in Europe, the U.S., and Japan. Its organization reflects the structure of corporate law across all jurisdictions, whil...

  3. Medico-legal problems in radiology

    International Nuclear Information System (INIS)

    Becker, W.

    1979-01-01

    The obligation of the pysician to inform the patient - which he has to prove in case of a suit - is based on the patient's right of selfdetermination. This self-dicision information was subject of the panel discussion. Not discussed in detail were the information concerning diagnosis and prognosis, and the instruction of the patient regarding his conduct postoperatively and during medical treatment. Not considered was the so-called malpractice and negligence respectively. Medical liability suits are increasing for various reasons and are frequently directed at a failure to inform the patient because the patient is often unable to prove a negligence of the physician ('surrogate liability'). The dimension of the duty of disclosure (complete information - no information at all) is discussed in general and with special regard to the radiological field. (orig.) [de

  4. Should Drugs Be Legalized?

    Science.gov (United States)

    Chambliss, William; Scorza, Thomas

    1989-01-01

    Presents two opposing viewpoints concerning the legalization of drugs. States that control efforts are not cost effective and suggests that legalization with efforts at education is a better course of action (W. Chambliss). The opposing argument contends that the cost in human suffering negates any savings in dollars gained through legalization…

  5. Constitutional Legal Regulation And The Reasons For The Legal Nihilism Existence In Modern Russian Society

    Directory of Open Access Journals (Sweden)

    Dmitriy E. Nekrasov

    2014-09-01

    Full Text Available In the present article questions of constitutional and legal regulation and reason for the legal nihilism existence, methods and forms of fight against legal nihilism are considered. Reasons of low legal culture in modern Russian society and ways of the population's legal literacy increase in general are allocated. These problems are extremely topical today as at the 1990th when there was a reorientation of values, ideals and the principles and legislative base was significantly changed, people were simply lost, and it was extremely difficult for them to realize and accept new, absolutely other reality. Today peculiar spiritual and valuable "reconstruct" did not pass completely and the state is obliged to help citizens to carry out it most without serious consequences and successfully. In the conclusion authors draw a conclusion that: first, the problem of legal nihilism more than ever now is particularly acute for modern Russian society. The policy of the state has to be directed by the consciousness of citizens, who understand that law is the integral and obligatory part of the order in the country and that it is one of the basic for any person. Secondly, one of the ways to overcome the legal nihilism consists in the increase of the legal culture level along with the development of effective legal policy. Thirdly, legal idealism, reevaluation of opportunities in law gains especially wide circulation in the years of changes in response to social expectations an insufficiently skilled legislator forms a belief that it is enough to adopt good laws, and all problems would be solved.

  6. Numerical solver for compressible two-fluid flow

    NARCIS (Netherlands)

    J. Naber (Jorick)

    2005-01-01

    textabstractThis report treats the development of a numerical solver for the simulation of flows of two non-mixing fluids described by the two-dimensional Euler equations. A level-set equation in conservative form describes the interface. After each time step the deformed level-set function is

  7. Using a satisfiability solver to identify deterministic finite state automata

    NARCIS (Netherlands)

    Heule, M.J.H.; Verwer, S.

    2009-01-01

    We present an exact algorithm for identification of deterministic finite automata (DFA) which is based on satisfiability (SAT) solvers. Despite the size of the low level SAT representation, our approach seems to be competitive with alternative techniques. Our contributions are threefold: First, we

  8. A High Performance QDWH-SVD Solver using Hardware Accelerators

    KAUST Repository

    Sukkari, Dalal E.; Ltaief, Hatem; Keyes, David E.

    2015-01-01

    few digits of accuracy, compared to the full double precision floating point arithmetic. We further leverage the single GPU QDWH-SVD implementation by introducing the first multi-GPU SVD solver to study the scalability of the QDWH-SVD framework.

  9. Hypersonic simulations using open-source CFD and DSMC solvers

    Science.gov (United States)

    Casseau, V.; Scanlon, T. J.; John, B.; Emerson, D. R.; Brown, R. E.

    2016-11-01

    Hypersonic hybrid hydrodynamic-molecular gas flow solvers are required to satisfy the two essential requirements of any high-speed reacting code, these being physical accuracy and computational efficiency. The James Weir Fluids Laboratory at the University of Strathclyde is currently developing an open-source hybrid code which will eventually reconcile the direct simulation Monte-Carlo method, making use of the OpenFOAM application called dsmcFoam, and the newly coded open-source two-temperature computational fluid dynamics solver named hy2Foam. In conjunction with employing the CVDV chemistry-vibration model in hy2Foam, novel use is made of the QK rates in a CFD solver. In this paper, further testing is performed, in particular with the CFD solver, to ensure its efficacy before considering more advanced test cases. The hy2Foam and dsmcFoam codes have shown to compare reasonably well, thus providing a useful basis for other codes to compare against.

  10. Implementing parallel elliptic solver on a Beowulf cluster

    Directory of Open Access Journals (Sweden)

    Marcin Paprzycki

    1999-12-01

    Full Text Available In a recent paper cite{zara} a parallel direct solver for the linear systems arising from elliptic partial differential equations has been proposed. The aim of this note is to present the initial evaluation of the performance characteristics of this algorithm on Beowulf-type cluster. In this context the performance of PVM and MPI based implementations is compared.

  11. Implementation of Generalized Adjoint Equation Solver for DeCART

    International Nuclear Information System (INIS)

    Han, Tae Young; Cho, Jin Young; Lee, Hyun Chul; Noh, Jae Man

    2013-01-01

    In this paper, the generalized adjoint solver based on the generalized perturbation theory is implemented on DeCART and the verification calculations were carried out. As the results, the adjoint flux for the general response coincides with the reference solution and it is expected that the solver could produce the parameters for the sensitivity and uncertainty analysis. Recently, MUSAD (Modules of Uncertainty and Sensitivity Analysis for DeCART) was developed for the uncertainty analysis of PMR200 core and the fundamental adjoint solver was implemented into DeCART. However, the application of the code was limited to the uncertainty to the multiplication factor, k eff , because it was based on the classical perturbation theory. For the uncertainty analysis to the general response as like the power density, it is necessary to develop the analysis module based on the generalized perturbation theory and it needs the generalized adjoint solutions from DeCART. In this paper, the generalized adjoint solver is implemented on DeCART and the calculation results are compared with the results by TSUNAMI of SCALE 6.1

  12. A Parallel Algebraic Multigrid Solver on Graphics Processing Units

    KAUST Repository

    Haase, Gundolf; Liebmann, Manfred; Douglas, Craig C.; Plank, Gernot

    2010-01-01

    -vector multiplication scheme underlying the PCG-AMG algorithm is presented for the many-core GPU architecture. A performance comparison of the parallel solver shows that a singe Nvidia Tesla C1060 GPU board delivers the performance of a sixteen node Infiniband cluster

  13. Analysis of transient plasmonic interactions using an MOT-PMCHWT integral equation solver

    KAUST Repository

    Uysal, Ismail Enes; Ulku, Huseyin Arda; Bagci, Hakan

    2014-01-01

    that discretize only on the interfaces. Additionally, IE solvers implicitly enforce the radiation condition and consequently do not need (approximate) absorbing boundary conditions. Despite these advantages, IE solvers, especially in time domain, have not been

  14. Methodology in Legal Research

    Directory of Open Access Journals (Sweden)

    Tom R. Tyler

    2017-12-01

    Full Text Available Recent legal scholarship demonstrates increased attention to empirical research in the design and evaluation of law and the policies and practices of legal authorities. The growth of evidence informed law is an exciting development and one that promises to improve the legal system. In this paper I argue for the particular value of drawing not just upon empirical research methods when evaluating existing policies and practices but upon social science theories. Theory based research provides a basis for imagining and testing different models about how the legal system might operate. I support this argument by presenting research on social science frameworks for legal authority which are alternatives to the currently prevalent instrumental model.

  15. A High Performance QDWH-SVD Solver using Hardware Accelerators

    KAUST Repository

    Sukkari, Dalal E.

    2015-04-08

    This paper describes a new high performance implementation of the QR-based Dynamically Weighted Halley Singular Value Decomposition (QDWH-SVD) solver on multicore architecture enhanced with multiple GPUs. The standard QDWH-SVD algorithm was introduced by Nakatsukasa and Higham (SIAM SISC, 2013) and combines three successive computational stages: (1) the polar decomposition calculation of the original matrix using the QDWH algorithm, (2) the symmetric eigendecomposition of the resulting polar factor to obtain the singular values and the right singular vectors and (3) the matrix-matrix multiplication to get the associated left singular vectors. A comprehensive test suite highlights the numerical robustness of the QDWH-SVD solver. Although it performs up to two times more flops when computing all singular vectors compared to the standard SVD solver algorithm, our new high performance implementation on single GPU results in up to 3.8x improvements for asymptotic matrix sizes, compared to the equivalent routines from existing state-of-the-art open-source and commercial libraries. However, when only singular values are needed, QDWH-SVD is penalized by performing up to 14 times more flops. The singular value only implementation of QDWH-SVD on single GPU can still run up to 18% faster than the best existing equivalent routines. Integrating mixed precision techniques in the solver can additionally provide up to 40% improvement at the price of losing few digits of accuracy, compared to the full double precision floating point arithmetic. We further leverage the single GPU QDWH-SVD implementation by introducing the first multi-GPU SVD solver to study the scalability of the QDWH-SVD framework.

  16. The latitude of logic in legal hermeneutics

    Directory of Open Access Journals (Sweden)

    Medar Suzana

    2014-01-01

    Full Text Available Legal hermeneutics (the interpretation of law] has always taken a highly significant place in general hermeneutics. The interpretation of laws involves an intricate task of determining the real meaning or rationale of legal norms. Considering the complexity of this goal, the most frequent classification of legal hermeneutics is based on the interpretation instruments. In traditional theory, the most widely recognized instruments for the interpretation of legal norms are language, logic, legal system, history and purpose of a legal norm. Under the influence of general analytic philosophy, the particular interest in language as the basic instrument for the interpretation of law may be found in mid-20th century. The interest in the language of law is closely related to the study of legal logic and legal argumentation. In theory, there is no dispute about the logical interpretation in a narrow sense which is based on drawing true conclusions by applying the basic rule of formal reasoning. Yet, it has given a head start to argumentation as 'a problem-based reasoning skill' which provides answers to the questions raised in contentious cases. Argumentation is closely associated with the dialectic method of reasoning (which has been widely recognized since the Ancient Greece], where conclusions are based on probable premises. One of the most significant goals of the argumentation theory is to locate the sources or common grounds for developing arguments; these basic argumentative patterns are generally known as 'topoi' or 'loci, sedes argumentorum'. On the other hand, 'topica' is part of rhetoric art dealing with the theoretical explanation of the basic argumentative patterns (topoi] and how they are structured, including the location of new topoi and arguments. The most significant proponents of the topical reasoning are Chaïm Perelman and Theodor Viehweg. Perelman relates topical reasoning to judicial reasoning and considers that specific legal topoi

  17. Memory transfer optimization for a lattice Boltzmann solver on Kepler architecture nVidia GPUs

    Science.gov (United States)

    Mawson, Mark J.; Revell, Alistair J.

    2014-10-01

    The Lattice Boltzmann method (LBM) for solving fluid flow is naturally well suited to an efficient implementation for massively parallel computing, due to the prevalence of local operations in the algorithm. This paper presents and analyses the performance of a 3D lattice Boltzmann solver, optimized for third generation nVidia GPU hardware, also known as 'Kepler'. We provide a review of previous optimization strategies and analyse data read/write times for different memory types. In LBM, the time propagation step (known as streaming), involves shifting data to adjacent locations and is central to parallel performance; here we examine three approaches which make use of different hardware options. Two of which make use of 'performance enhancing' features of the GPU; shared memory and the new shuffle instruction found in Kepler based GPUs. These are compared to a standard transfer of data which relies instead on optimized storage to increase coalesced access. It is shown that the more simple approach is most efficient; since the need for large numbers of registers per thread in LBM limits the block size and thus the efficiency of these special features is reduced. Detailed results are obtained for a D3Q19 LBM solver, which is benchmarked on nVidia K5000M and K20C GPUs. In the latter case the use of a read-only data cache is explored, and peak performance of over 1036 Million Lattice Updates Per Second (MLUPS) is achieved. The appearance of a periodic bottleneck in the solver performance is also reported, believed to be hardware related; spikes in iteration-time occur with a frequency of around 11 Hz for both GPUs, independent of the size of the problem.

  18. Riemann solvers for multi-component gas mixtures with temperature dependent heat capacities

    International Nuclear Information System (INIS)

    Beccantini, A.

    2001-01-01

    This thesis represents a contribution to the development of upwind splitting schemes for the Euler equations for ideal gaseous mixtures and their investigation in computing multidimensional flows in irregular geometries. In the preliminary part we develop and investigate the parameterization of the shock and rarefaction curves in the phase space. Then, we apply them to perform some field-by-field decompositions of the Riemann problem: the entropy-respecting one, the one which supposes that genuinely-non-linear (GNL) waves are both shocks (shock-shock one) and the one which supposes that GNL waves are both rarefactions (rarefaction-rarefaction one). We emphasize that their analysis is fundamental in Riemann solvers developing: the simpler the field-by-field decomposition, the simpler the Riemann solver based on it. As the specific heat capacities of the gases depend on the temperature, the shock-shock field-by-field decomposition is the easiest to perform. Then, in the second part of the thesis, we develop an upwind splitting scheme based on such decomposition. Afterwards, we investigate its robustness, precision and CPU-time consumption, with respect to some of the most popular upwind splitting schemes for polytropic/non-polytropic ideal gases. 1-D test-cases show that this scheme is both precise (exact capturing of stationary shock and stationary contact) and robust in dealing with strong shock and rarefaction waves. Multidimensional test-cases show that it suffers from some of the typical deficiencies which affect the upwind splitting schemes capable of exact capturing stationary contact discontinuities i.e the developing of non-physical instabilities in computing strong shock waves. In the final part, we use the high-order multidimensional solver here developed to compute fully-developed detonation flows. (author)

  19. Ethical issues in medico-legal exposures

    International Nuclear Information System (INIS)

    O'Reilly, G.; Malone, J. F.

    2008-01-01

    The Medical Exposure Directive (MED) 97/43/Euratom defines medico-legal procedures as 'procedures performed for insurance or legal purposes without a medical indication'. The term 'medico-legal exposures' covers a wide range of possible types of exposures, very different in nature, for which the only feature in common is the fact that the main reason for performing them does not relate directly to the health of the individual being exposed to ionising radiation. The key issue in medico-legal exposures is justification. Balancing the advantages and disadvantages of such exposures is complex because not only can these be difficult to quantify and hence compare, but often the advantage may be to society whereas the disadvantage is usually to an individual. This adds an additional layer of ethical complexity to the problem and one, which requires input from a number of sources beyond the established radiation protection community. Because medico-legal exposures are considered to be medical exposures, they are not subject to dose limits. In medico-legal exposures where the benefit is not necessarily to the individual undergoing the exposure, the question must be asked as to whether or not this is an appropriate framework within which to conduct such exposures. This paper looks at the current situation in Europe, highlighting some of the particular problems that have arisen, and tries to identify the areas, which require further clarification and guidance. (authors)

  20. Toward robust scalable algebraic multigrid solvers

    International Nuclear Information System (INIS)

    Waisman, Haim; Schroder, Jacob; Olson, Luke; Hiriyur, Badri; Gaidamour, Jeremie; Siefert, Christopher; Hu, Jonathan Joseph; Tuminaro, Raymond Stephen

    2010-01-01

    This talk highlights some multigrid challenges that arise from several application areas including structural dynamics, fluid flow, and electromagnetics. A general framework is presented to help introduce and understand algebraic multigrid methods based on energy minimization concepts. Connections between algebraic multigrid prolongators and finite element basis functions are made to explored. It is shown how the general algebraic multigrid framework allows one to adapt multigrid ideas to a number of different situations. Examples are given corresponding to linear elasticity and specifically in the solution of linear systems associated with extended finite elements for fracture problems.

  1. Abortion legalized: challenges ahead.

    Science.gov (United States)

    Singh, M; Jha, R

    2007-01-01

    To see whether advocacy for abortion law and comprehensive abortion care (CAC) sites after legalization of abortion in Nepal is adequate among educated people (above school leaving certificate). 150 participants were assigned randomly who agreed to be in the survey and were given structured questionnaires to find out their perception of abortion and CAC sites. Majority know abortion is legalized and majority have positive attitude about legalization of abortion, however majority are not aware of abortion service in CAC sites and none knew the cost of abortion service. Proper and adequate advocacy of the new abortion law and CAC service is essential.

  2. Efficient Parallel Kernel Solvers for Computational Fluid Dynamics Applications

    Science.gov (United States)

    Sun, Xian-He

    1997-01-01

    Distributed-memory parallel computers dominate today's parallel computing arena. These machines, such as Intel Paragon, IBM SP2, and Cray Origin2OO, have successfully delivered high performance computing power for solving some of the so-called "grand-challenge" problems. Despite initial success, parallel machines have not been widely accepted in production engineering environments due to the complexity of parallel programming. On a parallel computing system, a task has to be partitioned and distributed appropriately among processors to reduce communication cost and to attain load balance. More importantly, even with careful partitioning and mapping, the performance of an algorithm may still be unsatisfactory, since conventional sequential algorithms may be serial in nature and may not be implemented efficiently on parallel machines. In many cases, new algorithms have to be introduced to increase parallel performance. In order to achieve optimal performance, in addition to partitioning and mapping, a careful performance study should be conducted for a given application to find a good algorithm-machine combination. This process, however, is usually painful and elusive. The goal of this project is to design and develop efficient parallel algorithms for highly accurate Computational Fluid Dynamics (CFD) simulations and other engineering applications. The work plan is 1) developing highly accurate parallel numerical algorithms, 2) conduct preliminary testing to verify the effectiveness and potential of these algorithms, 3) incorporate newly developed algorithms into actual simulation packages. The work plan has well achieved. Two highly accurate, efficient Poisson solvers have been developed and tested based on two different approaches: (1) Adopting a mathematical geometry which has a better capacity to describe the fluid, (2) Using compact scheme to gain high order accuracy in numerical discretization. The previously developed Parallel Diagonal Dominant (PDD) algorithm

  3. Fast Solvers for Cahn--Hilliard Inpainting

    KAUST Repository

    Bosch, Jessica; Kay, David; Stoll, Martin; Wathen, Andrew J.

    2014-01-01

    The solution of Cahn-Hilliard variational inequalities is of interest in many applications. We discuss the use of them as a tool for binary image inpainting. This has been done before using double-well potentials but not for nonsmooth potentials as considered here. The existing bound constraints are incorporated via the Moreau-Yosida regularization technique. We develop effective preconditioners for the efficient solution of the Newton steps associated with the fast solution of the Moreau-Yosida regularized problem. Numerical results illustrate the efficiency of our approach. Moreover, precise eigenvalue intervals are given for the preconditioned system using a double-well potential. A comparison between the smooth and nonsmooth Cahn-Hilliard inpainting models shows that the latter achieves better results. © 2014 Society for Industrial and Applied Mathematics.

  4. Fast Solvers for Cahn--Hilliard Inpainting

    KAUST Repository

    Bosch, Jessica

    2014-01-02

    The solution of Cahn-Hilliard variational inequalities is of interest in many applications. We discuss the use of them as a tool for binary image inpainting. This has been done before using double-well potentials but not for nonsmooth potentials as considered here. The existing bound constraints are incorporated via the Moreau-Yosida regularization technique. We develop effective preconditioners for the efficient solution of the Newton steps associated with the fast solution of the Moreau-Yosida regularized problem. Numerical results illustrate the efficiency of our approach. Moreover, precise eigenvalue intervals are given for the preconditioned system using a double-well potential. A comparison between the smooth and nonsmooth Cahn-Hilliard inpainting models shows that the latter achieves better results. © 2014 Society for Industrial and Applied Mathematics.

  5. Periodic Poisson Solver for Particle Tracking

    International Nuclear Information System (INIS)

    Dohlus, M.; Henning, C.

    2015-05-01

    A method is described to solve the Poisson problem for a three dimensional source distribution that is periodic into one direction. Perpendicular to the direction of periodicity a free space (or open) boundary is realized. In beam physics, this approach allows to calculate the space charge field of a continualized charged particle distribution with periodic pattern. The method is based on a particle mesh approach with equidistant grid and fast convolution with a Green's function. The periodic approach uses only one period of the source distribution, but a periodic extension of the Green's function. The approach is numerically efficient and allows the investigation of periodic- and pseudo-periodic structures with period lengths that are small compared to the source dimensions, for instance of laser modulated beams or of the evolution of micro bunch structures. Applications for laser modulated beams are given.

  6. Scalability of Direct Solver for Non-stationary Cahn-Hilliard Simulations with Linearized time Integration Scheme

    KAUST Repository

    Woźniak, M.

    2016-06-02

    We study the features of a new mixed integration scheme dedicated to solving the non-stationary variational problems. The scheme is composed of the FEM approximation with respect to the space variable coupled with a 3-leveled time integration scheme with a linearized right-hand side operator. It was applied in solving the Cahn-Hilliard parabolic equation with a nonlinear, fourth-order elliptic part. The second order of the approximation along the time variable was proven. Moreover, the good scalability of the software based on this scheme was confirmed during simulations. We verify the proposed time integration scheme by monitoring the Ginzburg-Landau free energy. The numerical simulations are performed by using a parallel multi-frontal direct solver executed over STAMPEDE Linux cluster. Its scalability was compared to the results of the three direct solvers, including MUMPS, SuperLU and PaSTiX.

  7. Fast Poisson Solvers for Self-Consistent Beam-Beam and Space-Charge Field Computation in Multiparticle Tracking Simulations

    CERN Document Server

    Florio, Adrien; Pieloni, Tatiana; CERN. Geneva. ATS Department

    2015-01-01

    We present two different approaches to solve the 2-dimensional electrostatic problem with open boundary conditions to be used in fast tracking codes for beam-beam and space charge simulations in high energy accelerators. We compare a fast multipoles method with a hybrid Poisson solver based on the fast Fourier transform and finite differences in polar coordinates. We show that the latter outperforms the first in terms of execution time and precision, allowing for a reduction of the noise in the tracking simulation. Furthermore the new algorithm is shown to scale linearly on parallel architectures with shared memory. We conclude by effectively replacing the HFMM by the new Poisson solver in the COMBI code.

  8. A direct solver with reutilization of LU factorizations for h-adaptive finite element grids with point singularities

    KAUST Repository

    Paszyński, Maciej R.

    2013-04-01

    This paper describes a direct solver algorithm for a sequence of finite element meshes that are h-refined towards one or several point singularities. For such a sequence of grids, the solver delivers linear computational cost O(N) in terms of CPU time and memory with respect to the number of unknowns N. The linear computational cost is achieved by utilizing the recursive structure provided by the sequence of h-adaptive grids with a special construction of the elimination tree that allows for reutilization of previously computed partial LU (or Cholesky) factorizations over the entire unrefined part of the computational mesh. The reutilization technique reduces the computational cost of the entire sequence of h-refined grids from O(N2) down to O(N). Theoretical estimates are illustrated with numerical results on two- and three-dimensional model problems exhibiting one or several point singularities. © 2013 Elsevier Ltd. All rights reserved.

  9. A high-order finite-difference linear seakeeping solver tool for calculation of added resistance in waves

    DEFF Research Database (Denmark)

    Amini Afshar, Mostafa; Bingham, Harry B.; Read, Robert

    During recent years a computational strategy has been developed at the Technical University of Denmark for numerical simulation of water wave problems based on the high-order nite-dierence method, [2],[4]. These methods exhibit a linear scaling of the computational eort as the number of grid points...... increases. This understanding is being applied to develop a tool for predicting the added resistance (drift force) of ships in ocean waves. We expect that the optimal scaling properties of this solver will allow us to make a convincing demonstration of convergence of the added resistance calculations based...... on both near-eld and far-eld methods. The solver has been written inside a C++ library known as Overture [3], which can be used to solve partial dierential equations on overlapping grids based on the high-order nite-dierence method. The resulting code is able to solve, in the time domain, the linearised...

  10. A direct solver with reutilization of LU factorizations for h-adaptive finite element grids with point singularities

    KAUST Repository

    Paszyński, Maciej R.; Calo, Victor M.; Pardo, David

    2013-01-01

    This paper describes a direct solver algorithm for a sequence of finite element meshes that are h-refined towards one or several point singularities. For such a sequence of grids, the solver delivers linear computational cost O(N) in terms of CPU time and memory with respect to the number of unknowns N. The linear computational cost is achieved by utilizing the recursive structure provided by the sequence of h-adaptive grids with a special construction of the elimination tree that allows for reutilization of previously computed partial LU (or Cholesky) factorizations over the entire unrefined part of the computational mesh. The reutilization technique reduces the computational cost of the entire sequence of h-refined grids from O(N2) down to O(N). Theoretical estimates are illustrated with numerical results on two- and three-dimensional model problems exhibiting one or several point singularities. © 2013 Elsevier Ltd. All rights reserved.

  11. Gerenciamento de riscos na prática ortodôntica: como se proteger de eventuais problemas legais Risk management in orthodontic practice: how to avoid legal problems

    Directory of Open Access Journals (Sweden)

    Ricardo Machado Cruz

    2008-02-01

    Full Text Available INTRODUÇÃO: A relação profissional-paciente na área de Ortodontia e Ortopedia facial é bastante desgastante face à longa duração dos tratamentos e, por causa disso, muitas vezes essa relação pode se deteriorar trazendo prejuízos a ambas as partes. OBJETIVO: Este trabalho visa informar o leitor, em linguagem acessível, sobre os principais problemas jurídicos que podem envolver o ortodontista em sua prática profissional, nas esferas cíveis, criminais e trabalhistas, bem como dos Conselhos Regionais de Odontologia. METODOLOGIA: Traça um perfil da atividade profissional em Ortodontia, analisa deveres e direitos do profissional e do paciente e estabelece alguns conceitos de gerenciamento de riscos a serem incorporados à clínica diária. RESULTADO E CONCLUSÃO: Além de trabalhar bem tecnicamente e com bom embasamento científico, o ortodontista atual deve saber como se prevenir de eventuais problemas legais. Este trabalho poderá servir como ferramenta de consulta para o estabelecimento de uma nova rotina clínica, administrativa e de relacionamento que seja mais segura do ponto de vista jurídico.INTRODUCTION: The professional relationship between the orthodontist and his patient is very consuming due to the long duration of clinical treatments. Frequently this relationship can be deteriorated causing damages to both sides. AIM: This paper aims to inform the reader, in an accessible language, about the main juridical problems that can involve the orthodontist in his practice, in the field of civil, criminal and labor law. METHODOLOGY: This paper draws the outline of professional activity in orthodontics, analyses obligations and rights of both orthodontists and patients and establishes some concepts of risk management that should be incorporated to the clinical practice. RESULTS AND CONCLUSION: Besides technically good and scientifically based work, orthodontists should know how to avoid legal problems. This paper can be an

  12. A fast nonlinear conjugate gradient based method for 3D concentrated frictional contact problems

    NARCIS (Netherlands)

    J. Zhao (Jing); E.A.H. Vollebregt (Edwin); C.W. Oosterlee (Cornelis)

    2015-01-01

    htmlabstractThis paper presents a fast numerical solver for a nonlinear constrained optimization problem, arising from 3D concentrated frictional shift and rolling contact problems with dry Coulomb friction. The solver combines an active set strategy with a nonlinear conjugate gradient method. One

  13. Problem solving stages in the five square problem.

    Science.gov (United States)

    Fedor, Anna; Szathmáry, Eörs; Öllinger, Michael

    2015-01-01

    According to the restructuring hypothesis, insight problem solving typically progresses through consecutive stages of search, impasse, insight, and search again for someone, who solves the task. The order of these stages was determined through self-reports of problem solvers and has never been verified behaviorally. We asked whether individual analysis of problem solving attempts of participants revealed the same order of problem solving stages as defined by the theory and whether their subjective feelings corresponded to the problem solving stages they were in. Our participants tried to solve the Five-Square problem in an online task, while we recorded the time and trajectory of their stick movements. After the task they were asked about their feelings related to insight and some of them also had the possibility of reporting impasse while working on the task. We found that the majority of participants did not follow the classic four-stage model of insight, but had more complex sequences of problem solving stages, with search and impasse recurring several times. This means that the classic four-stage model is not sufficient to describe variability on the individual level. We revised the classic model and we provide a new model that can generate all sequences found. Solvers reported insight more often than non-solvers and non-solvers reported impasse more often than solvers, as expected; but participants did not report impasse more often during behaviorally defined impasse stages than during other stages. This shows that impasse reports might be unreliable indicators of impasse. Our study highlights the importance of individual analysis of problem solving behavior to verify insight theory.

  14. Constrained Quadratic Programming and Neurodynamics-Based Solver for Energy Optimization of Biped Walking Robots

    Directory of Open Access Journals (Sweden)

    Liyang Wang

    2017-01-01

    Full Text Available The application of biped robots is always trapped by their high energy consumption. This paper makes a contribution by optimizing the joint torques to decrease the energy consumption without changing the biped gaits. In this work, a constrained quadratic programming (QP problem for energy optimization is formulated. A neurodynamics-based solver is presented to solve the QP problem. Differing from the existing literatures, the proposed neurodynamics-based energy optimization (NEO strategy minimizes the energy consumption and guarantees the following three important constraints simultaneously: (i the force-moment equilibrium equation of biped robots, (ii frictions applied by each leg on the ground to hold the biped robot without slippage and tipping over, and (iii physical limits of the motors. Simulations demonstrate that the proposed strategy is effective for energy-efficient biped walking.

  15. Whistleblowing: a legal commentary.

    Science.gov (United States)

    Cornock, Marc

    2011-10-01

    This article examines the legal position of a nurse who believes that a colleague is performing below the level of competence required, witnesses inappropriate action by a colleague, or who believes that the care environment is putting patients at risk.

  16. Legal culture: characteristics and specifics (on the example of contemporary Kazakhstan

    Directory of Open Access Journals (Sweden)

    G R Absattarov

    2014-12-01

    Full Text Available The article considers the legal culture as an ‘ideal phenomenon’ providing value meanings for the outlook of the Kazakhs and the basis for the development of the population legal consciousness. The author focuses on the national significance of the legal, civil society and the development of new legal social ideals, norms and rules, examines key problems and contradictions in the legal culture of today’s Kazakhstan.

  17. On the obstacles and solutions in the application of Chinese criminal legal aid system

    Directory of Open Access Journals (Sweden)

    Wang Sh.

    2016-06-01

    Full Text Available the article discovers the problem of application of Chinese legal aid system, which is very low. The problem should be solved as below. The author suggests strengthening the education to investigators, changing the way of employing legal aid lawyers and clarify the content of the right informing and applying for legal aid system. These actions application might well improve the situation.

  18. Legal Aspects of Telepathology

    Directory of Open Access Journals (Sweden)

    Christian Dierks

    2000-01-01

    Full Text Available In some legal surroundings telepathology is considered a breach of registrational barriers. The recommendation of the G 8 states in Europe for required legislation in telemedicine suggests to recognise that the localization of the remote health care professional defines the site not only of licensure but also of liability. This approach must be considered helpful, since it can solve many problems brought about by the doubtful results of private international law and conventions like the European Union (EU and Lugano Convention. Under today's conditions in private international law it must be considered essential to agree upon a choice of law and stipulate a court of jurisdiction when doing telepathology. However, the opposing aims of insuring the patients claims and avoiding jurisdictions that exceed the local expectations of the medical professional must be reconciled. Data protection and data security are other crucial topics that require attention. Generally speaking, the principles of minimum data exchange, anonymity, pseudonymity and cryptography must be established as a basis for all telepathology procedures. Only when personal data is needed, its use can be legitimated. Written consent of the patient is advised. To guarantee a cross‐border security level the regulations of the EU‐Data Protection Directive need to be transformed into national law. In practise, cross‐border dataflow shall only take place where the security level can be maintained even within the other country. Finally, reimbursement questions must be answered to establish a sound economical basis for telepathology. The spatial distance between the participants may yield the question, whether the service has been rendered to an extent necessary and sufficient for reimbursement. If reimbursement takes place on a cross‐border or cross‐regional level, severe disturbances of the health systems can occur. Regulation schemes or treaties need therefore to be developed to

  19. Application of GPU to Multi-interfaces Advection and Reconstruction Solver (MARS)

    International Nuclear Information System (INIS)

    Nagatake, Taku; Takase, Kazuyuki; Kunugi, Tomoaki

    2010-01-01

    In the nuclear engineering fields, a high performance computer system is necessary to perform the large scale computations. Recently, a Graphics Processing Unit (GPU) has been developed as a rendering computational system in order to reduce a Central Processing Unit (CPU) load. In the graphics processing, the high performance computing is needed to render the high-quality 3D objects in some video games. Thus the GPU consists of many processing units and a wide memory bandwidth. In this study, the Multi-interfaces Advection and Reconstruction Solver (MARS) which is one of the interface volume tracking methods for multi-phase flows has been performed. The multi-phase flow computation is very important for the nuclear reactors and other engineering fields. The MARS consists of two computing parts: the interface tracking part and the fluid motion computing part. As for the interface tracking part, the performance of GPU (GTX280) was 6 times faster than that of the CPU (Dual-Xeon 5040), and in the fluid motion computing part the Poisson Solver by the GPU (GTX285) was 22 times faster than that by the CPU(Core i7). As for the Dam Breaking Problem, the result of GPU-MARS showed slightly different from the experimental result. Because the GPU-MARS was developed using the single-precision GPU, it can be considered that the round-off error might be accumulated. (author)

  20. Parallelization of pressure equation solver for incompressible N-S equations

    International Nuclear Information System (INIS)

    Ichihara, Kiyoshi; Yokokawa, Mitsuo; Kaburaki, Hideo.

    1996-03-01

    A pressure equation solver in a code for 3-dimensional incompressible flow analysis has been parallelized by using red-black SOR method and PCG method on Fujitsu VPP500, a vector parallel computer with distributed memory. For the comparison of scalability, the solver using the red-black SOR method has been also parallelized on the Intel Paragon, a scalar parallel computer with a distributed memory. The scalability of the red-black SOR method on both VPP500 and Paragon was lost, when number of processor elements was increased. The reason of non-scalability on both systems is increasing communication time between processor elements. In addition, the parallelization by DO-loop division makes the vectorizing efficiency lower on VPP500. For an effective implementation on VPP500, a large scale problem which holds very long vectorized DO-loops in the parallel program should be solved. PCG method with red-black SOR method applied to incomplete LU factorization (red-black PCG) has more iteration steps than normal PCG method with forward and backward substitution, in spite of same number of the floating point operations in a DO-loop of incomplete LU factorization. The parallelized red-black PCG method has less merits than the parallelized red-black SOR method when the computational region has fewer grids, because the low vectorization efficiency is obtained in red-black PCG method. (author)

  1. LSODKR, Stiff Ordinary Differential Equations (ODE) System Solver with Krylov Iteration and Root-finding

    International Nuclear Information System (INIS)

    Hindmarsh, A.D.; Brown, P.N.

    1996-01-01

    1 - Description of program or function: LSODKR is a new initial value ODE solver for stiff and non-stiff systems. It is a variant of the LSODPK and LSODE solvers, intended mainly for large stiff systems. The main differences between LSODKR and LSODE are the following: a) for stiff systems, LSODKR uses a corrector iteration composed of Newton iteration and one of four preconditioned Krylov subspace iteration methods. The user must supply routines for the preconditioning operations, b) within the corrector iteration, LSODKR does automatic switching between functional (fix point) iteration and modified Newton iteration, c) LSODKR includes the ability to find roots of given functions of the solution during the integration. 2 - Method of solution: Integration is by Adams or BDF (Backward Differentiation Formula) methods, at user option. Corrector iteration is by Newton or fix point iteration, determined dynamically. Linear system solution is by a preconditioned Krylov iteration, selected by user from Incomplete Orthogonalization Method, Generalized Minimum Residual Method, and two variants of Preconditioned Conjugate Gradient Method. Preconditioning is to be supplied by the user. 3 - Restrictions on the complexity of the problem: None

  2. Effective high-order solver with thermally perfect gas model for hypersonic heating prediction

    International Nuclear Information System (INIS)

    Jiang, Zhenhua; Yan, Chao; Yu, Jian; Qu, Feng; Ma, Libin

    2016-01-01

    Highlights: • Design proper numerical flux for thermally perfect gas. • Line-implicit LUSGS enhances efficiency without extra memory consumption. • Develop unified framework for both second-order MUSCL and fifth-order WENO. • The designed gas model can be applied to much wider temperature range. - Abstract: Effective high-order solver based on the model of thermally perfect gas has been developed for hypersonic heat transfer computation. The technique of polynomial curve fit coupling to thermodynamics equation is suggested to establish the current model and particular attention has been paid to the design of proper numerical flux for thermally perfect gas. We present procedures that unify five-order WENO (Weighted Essentially Non-Oscillatory) scheme in the existing second-order finite volume framework and a line-implicit method that improves the computational efficiency without increasing memory consumption. A variety of hypersonic viscous flows are performed to examine the capability of the resulted high order thermally perfect gas solver. Numerical results demonstrate its superior performance compared to low-order calorically perfect gas method and indicate its potential application to hypersonic heating predictions for real-life problem.

  3. Multilayer shallow shelf approximation: Minimisation formulation, finite element solvers and applications

    Energy Technology Data Exchange (ETDEWEB)

    Jouvet, Guillaume, E-mail: jouvet@vaw.baug.ethz.ch [Institut für Mathematik, Freie Universität Berlin (Germany); Laboratory of Hydraulics, Hydrology and Glaciology, ETH Zurich (Switzerland)

    2015-04-15

    In this paper, a multilayer generalisation of the Shallow Shelf Approximation (SSA) is considered. In this recent hybrid ice flow model, the ice thickness is divided into thin layers, which can spread out, contract and slide over each other in such a way that the velocity profile is layer-wise constant. Like the SSA (1-layer model), the multilayer model can be reformulated as a minimisation problem. However, unlike the SSA, the functional to be minimised involves a new penalisation term for the interlayer jumps of the velocity, which represents the vertical shear stresses induced by interlayer sliding. Taking advantage of this reformulation, numerical solvers developed for the SSA can be naturally extended layer-wise or column-wise. Numerical results show that the column-wise extension of a Newton multigrid solver proves to be robust in the sense that its convergence is barely influenced by the number of layers and the type of ice flow. In addition, the multilayer formulation appears to be naturally better conditioned than the one of the first-order approximation to face the anisotropic conditions of the sliding-dominant ice flow of ISMIP-HOM experiments.

  4. Design of a Modular Monolithic Implicit Solver for Multi-Physics Applications

    Science.gov (United States)

    Carton De Wiart, Corentin; Diosady, Laslo T.; Garai, Anirban; Burgess, Nicholas; Blonigan, Patrick; Ekelschot, Dirk; Murman, Scott M.

    2018-01-01

    The design of a modular multi-physics high-order space-time finite-element framework is presented together with its extension to allow monolithic coupling of different physics. One of the main objectives of the framework is to perform efficient high- fidelity simulations of capsule/parachute systems. This problem requires simulating multiple physics including, but not limited to, the compressible Navier-Stokes equations, the dynamics of a moving body with mesh deformations and adaptation, the linear shell equations, non-re effective boundary conditions and wall modeling. The solver is based on high-order space-time - finite element methods. Continuous, discontinuous and C1-discontinuous Galerkin methods are implemented, allowing one to discretize various physical models. Tangent and adjoint sensitivity analysis are also targeted in order to conduct gradient-based optimization, error estimation, mesh adaptation, and flow control, adding another layer of complexity to the framework. The decisions made to tackle these challenges are presented. The discussion focuses first on the "single-physics" solver and later on its extension to the monolithic coupling of different physics. The implementation of different physics modules, relevant to the capsule/parachute system, are also presented. Finally, examples of coupled computations are presented, paving the way to the simulation of the full capsule/parachute system.

  5. How does Investors' Legal Protection affect Productivity and Growth?

    OpenAIRE

    Binyamin Berdugo; Sharon Hadad

    2009-01-01

    This paper analyzes the implications of investors' legal protection on aggregate productivity and growth. We have two main results. First, that better investors' legal protection can mitigate agency problems between investors and innovators and therefore expand the range of high-tech projects that can be financed by non-bank investors. Second, investors' legal protection shifts investment resources from less productive (medium-tech) to highly productive (high-tech) projects and therefore enha...

  6. Legal liability and claims for the hotel industry

    OpenAIRE

    Dimcho Todorov

    2017-01-01

    The paper presents a review of various aspects of legal liability and claims to hotel management arising in the hotel industry in the context of the legal framework and possible legal consequences for hotels and other types of commercial accommodation establishments. The main reasons for accidents' occurrence in the hotel industry are chronologically traced. Possible claims to the hotel management are also presented in detail. The problem with workplace discrimination, which is considered as ...

  7. Should fully autonomous artificial intelligence systems be granted legal capacity?

    OpenAIRE

    Naučius, Mindaugas

    2018-01-01

    The aim of this article is to address the issue of granting legal capacity to artificial inteligence systems. In order to approach the solution to the problem addressed, the article includes several aspects, relevant in order to achieve it. To begin with, the general concept of legal capacity is introduced. Following this aspect, the main features of both natural and juridical persons are addressed, in order to become familiar with the content of legal capacity, or in other words, to be aware...

  8. Implementation of geomechanical models for engineered clay barriers in multi-physic partial differential equation solvers

    International Nuclear Information System (INIS)

    Navarro, V.; Alonso, J.; Asensio, L.; Yustres, A.; Pintado, X.

    2012-01-01

    Document available in extended abstract form only. The use of numerical methods, especially the Finite Element Method (FEM), for solving boundary problems in Unsaturated Soil Mechanics has experienced significant progress. Several codes, both built mainly for research purposes and commercial software, are now available. In the last years, Multi-physic Partial Differentiation Equation Solvers (MPDES) have turned out to be an interesting proposal. In this family of solvers, the user defines the governing equations and the behaviour models, generally using a computer algebra environment. The code automatically assembles and solves the equation systems, saving the user having to redefine the structures of memory storage or to implement solver algorithms. The user can focus on the definition of the physics of the problem, while it is possible to couple virtually any physical or chemical process that can be described by a PDE. This can be done, for instance, in COMSOL Multiphysics (CM). Nonetheless, the versatility of CM is compromised by the impossibility to implement models with variables defined by implicit functions. Elasto-plastic models involve an implicit coupling among stress increments, plastic strains and plastic variables increments. For this reason, they cannot be implemented in CM in a straightforward way. This means a very relevant limitation for the use of this tool in the analysis of geomechanical boundary value problems. In this work, a strategy to overcome this problem using the multi-physics concept is presented. A mixed method is proposed, considering the constitutive stresses, the pre-consolidation pressure and the plastic variables as main unknowns of the model. Mixed methods usually present stability problems. However, the algorithmics present in CM include several numerical strategies to minimise this kind of problems. Besides, CM is based on the application of the FEM with Lagrange multipliers, an approach that significantly contributes stability

  9. Benchmarking ICRF Full-wave Solvers for ITER

    International Nuclear Information System (INIS)

    Budny, R.V.; Berry, L.; Bilato, R.; Bonoli, P.; Brambilla, M.; Dumont, R.J.; Fukuyama, A.; Harvey, R.; Jaeger, E.F.; Indireshkumar, K.; Lerche, E.; McCune, D.; Phillips, C.K.; Vdovin, V.; Wright, J.

    2011-01-01

    Benchmarking of full-wave solvers for ICRF simulations is performed using plasma profiles and equilibria obtained from integrated self-consistent modeling predictions of four ITER plasmas. One is for a high performance baseline (5.3 T, 15 MA) DT H-mode. The others are for half-field, half-current plasmas of interest for the pre-activation phase with bulk plasma ion species being either hydrogen or He4. The predicted profiles are used by six full-wave solver groups to simulate the ICRF electromagnetic fields and heating, and by three of these groups to simulate the current-drive. Approximate agreement is achieved for the predicted heating power for the DT and He4 cases. Factor of two disagreements are found for the cases with second harmonic He3 heating in bulk H cases. Approximate agreement is achieved simulating the ICRF current drive.

  10. Minaret, a deterministic neutron transport solver for nuclear core calculations

    International Nuclear Information System (INIS)

    Moller, J-Y.; Lautard, J-J.

    2011-01-01

    We present here MINARET a deterministic transport solver for nuclear core calculations to solve the steady state Boltzmann equation. The code follows the multi-group formalism to discretize the energy variable. It uses discrete ordinate method to deal with the angular variable and a DGFEM to solve spatially the Boltzmann equation. The mesh is unstructured in 2D and semi-unstructured in 3D (cylindrical). Curved triangles can be used to fit the exact geometry. For the curved elements, two different sets of basis functions can be used. Transport solver is accelerated with a DSA method. Diffusion and SPN calculations are made possible by skipping the transport sweep in the source iteration. The transport calculations are parallelized with respect to the angular directions. Numerical results are presented for simple geometries and for the C5G7 Benchmark, JHR reactor and the ESFR (in 2D and 3D). Straight and curved finite element results are compared. (author)

  11. Comparison of Einstein-Boltzmann solvers for testing general relativity

    Science.gov (United States)

    Bellini, E.; Barreira, A.; Frusciante, N.; Hu, B.; Peirone, S.; Raveri, M.; Zumalacárregui, M.; Avilez-Lopez, A.; Ballardini, M.; Battye, R. A.; Bolliet, B.; Calabrese, E.; Dirian, Y.; Ferreira, P. G.; Finelli, F.; Huang, Z.; Ivanov, M. M.; Lesgourgues, J.; Li, B.; Lima, N. A.; Pace, F.; Paoletti, D.; Sawicki, I.; Silvestri, A.; Skordis, C.; Umiltà, C.; Vernizzi, F.

    2018-01-01

    We compare Einstein-Boltzmann solvers that include modifications to general relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general scalar-tensor theories, three codes that model Jordan-Brans-Dicke (JBD) gravity, a code that models f (R ) gravity, a code that models covariant Galileons, a code that models Hořava-Lifschitz gravity, and two codes that model nonlocal models of gravity. Comparing predictions of the angular power spectrum of the cosmic microwave background and the power spectrum of dark matter for a suite of different models, we find agreement at the subpercent level. This means that this suite of Einstein-Boltzmann solvers is now sufficiently accurate for precision constraints on cosmological and gravitational parameters.

  12. Minaret, a deterministic neutron transport solver for nuclear core calculations

    Energy Technology Data Exchange (ETDEWEB)

    Moller, J-Y.; Lautard, J-J., E-mail: jean-yves.moller@cea.fr, E-mail: jean-jacques.lautard@cea.fr [CEA - Centre de Saclay , Gif sur Yvette (France)

    2011-07-01

    We present here MINARET a deterministic transport solver for nuclear core calculations to solve the steady state Boltzmann equation. The code follows the multi-group formalism to discretize the energy variable. It uses discrete ordinate method to deal with the angular variable and a DGFEM to solve spatially the Boltzmann equation. The mesh is unstructured in 2D and semi-unstructured in 3D (cylindrical). Curved triangles can be used to fit the exact geometry. For the curved elements, two different sets of basis functions can be used. Transport solver is accelerated with a DSA method. Diffusion and SPN calculations are made possible by skipping the transport sweep in the source iteration. The transport calculations are parallelized with respect to the angular directions. Numerical results are presented for simple geometries and for the C5G7 Benchmark, JHR reactor and the ESFR (in 2D and 3D). Straight and curved finite element results are compared. (author)

  13. An alternative solver for the nodal expansion method equations - 106

    International Nuclear Information System (INIS)

    Carvalho da Silva, F.; Carlos Marques Alvim, A.; Senra Martinez, A.

    2010-01-01

    An automated procedure for nuclear reactor core design is accomplished by using a quick and accurate 3D nodal code, aiming at solving the diffusion equation, which describes the spatial neutron distribution in the reactor. This paper deals with an alternative solver for nodal expansion method (NEM), with only two inner iterations (mesh sweeps) per outer iteration, thus having the potential to reduce the time required to calculate the power distribution in nuclear reactors, but with accuracy similar to the ones found in conventional NEM. The proposed solver was implemented into a computational system which, besides solving the diffusion equation, also solves the burnup equations governing the gradual changes in material compositions of the core due to fuel depletion. Results confirm the effectiveness of the method for practical purposes. (authors)

  14. A Nonlinear Modal Aeroelastic Solver for FUN3D

    Science.gov (United States)

    Goldman, Benjamin D.; Bartels, Robert E.; Biedron, Robert T.; Scott, Robert C.

    2016-01-01

    A nonlinear structural solver has been implemented internally within the NASA FUN3D computational fluid dynamics code, allowing for some new aeroelastic capabilities. Using a modal representation of the structure, a set of differential or differential-algebraic equations are derived for general thin structures with geometric nonlinearities. ODEPACK and LAPACK routines are linked with FUN3D, and the nonlinear equations are solved at each CFD time step. The existing predictor-corrector method is retained, whereby the structural solution is updated after mesh deformation. The nonlinear solver is validated using a test case for a flexible aeroshell at transonic, supersonic, and hypersonic flow conditions. Agreement with linear theory is seen for the static aeroelastic solutions at relatively low dynamic pressures, but structural nonlinearities limit deformation amplitudes at high dynamic pressures. No flutter was found at any of the tested trajectory points, though LCO may be possible in the transonic regime.

  15. CASTRO: A NEW COMPRESSIBLE ASTROPHYSICAL SOLVER. II. GRAY RADIATION HYDRODYNAMICS

    International Nuclear Information System (INIS)

    Zhang, W.; Almgren, A.; Bell, J.; Howell, L.; Burrows, A.

    2011-01-01

    We describe the development of a flux-limited gray radiation solver for the compressible astrophysics code, CASTRO. CASTRO uses an Eulerian grid with block-structured adaptive mesh refinement based on a nested hierarchy of logically rectangular variable-sized grids with simultaneous refinement in both space and time. The gray radiation solver is based on a mixed-frame formulation of radiation hydrodynamics. In our approach, the system is split into two parts, one part that couples the radiation and fluid in a hyperbolic subsystem, and another parabolic part that evolves radiation diffusion and source-sink terms. The hyperbolic subsystem is solved explicitly with a high-order Godunov scheme, whereas the parabolic part is solved implicitly with a first-order backward Euler method.

  16. Boltzmann Solver with Adaptive Mesh in Velocity Space

    International Nuclear Information System (INIS)

    Kolobov, Vladimir I.; Arslanbekov, Robert R.; Frolova, Anna A.

    2011-01-01

    We describe the implementation of direct Boltzmann solver with Adaptive Mesh in Velocity Space (AMVS) using quad/octree data structure. The benefits of the AMVS technique are demonstrated for the charged particle transport in weakly ionized plasmas where the collision integral is linear. We also describe the implementation of AMVS for the nonlinear Boltzmann collision integral. Test computations demonstrate both advantages and deficiencies of the current method for calculations of narrow-kernel distributions.

  17. Resolving Neighbourhood Relations in a Parallel Fluid Dynamic Solver

    KAUST Repository

    Frisch, Jerome

    2012-06-01

    Computational Fluid Dynamics simulations require an enormous computational effort if a physically reasonable accuracy should be reached. Therefore, a parallel implementation is inevitable. This paper describes the basics of our implemented fluid solver with a special aspect on the hierarchical data structure, unique cell and grid identification, and the neighbourhood relations in-between grids on different processes. A special server concept keeps track of every grid over all processes while minimising data transfer between the nodes. © 2012 IEEE.

  18. A contribution to the great Riemann solver debate

    Science.gov (United States)

    Quirk, James J.

    1992-01-01

    The aims of this paper are threefold: to increase the level of awareness within the shock capturing community to the fact that many Godunov-type methods contain subtle flaws that can cause spurious solutions to be computed; to identify one mechanism that might thwart attempts to produce very high resolution simulations; and to proffer a simple strategy for overcoming the specific failings of individual Riemann solvers.

  19. Applications of 3-D Maxwell solvers to accelerator design

    International Nuclear Information System (INIS)

    Chou, W.

    1990-01-01

    This paper gives a brief discussion on various applications of 3-D Maxwell solvers to accelerator design. The work is based on our experience gained during the design of the storage ring of the 7-GeV Advanced Photon Source (APS). It shows that 3-D codes are not replaceable in many cases, and that a lot of work remains to be done in order to establish a solid base for 3-D simulations

  20. An immersed interface vortex particle-mesh solver

    Science.gov (United States)

    Marichal, Yves; Chatelain, Philippe; Winckelmans, Gregoire

    2014-11-01

    An immersed interface-enabled vortex particle-mesh (VPM) solver is presented for the simulation of 2-D incompressible viscous flows, in the framework of external aerodynamics. Considering the simulation of free vortical flows, such as wakes and jets, vortex particle-mesh methods already provide a valuable alternative to standard CFD methods, thanks to the interesting numerical properties arising from its Lagrangian nature. Yet, accounting for solid bodies remains challenging, despite the extensive research efforts that have been made for several decades. The present immersed interface approach aims at improving the consistency and the accuracy of one very common technique (based on Lighthill's model) for the enforcement of the no-slip condition at the wall in vortex methods. Targeting a sharp treatment of the wall calls for substantial modifications at all computational levels of the VPM solver. More specifically, the solution of the underlying Poisson equation, the computation of the diffusion term and the particle-mesh interpolation are adapted accordingly and the spatial accuracy is assessed. The immersed interface VPM solver is subsequently validated on the simulation of some challenging impulsively started flows, such as the flow past a cylinder and that past an airfoil. Research Fellow (PhD student) of the F.R.S.-FNRS of Belgium.

  1. Direct solvers performance on h-adapted grids

    KAUST Repository

    Paszynski, Maciej; Pardo, David; Calo, Victor M.

    2015-01-01

    We analyse the performance of direct solvers when applied to a system of linear equations arising from an hh-adapted, C0C0 finite element space. Theoretical estimates are derived for typical hh-refinement patterns arising as a result of a point, edge, or face singularity as well as boundary layers. They are based on the elimination trees constructed specifically for the considered grids. Theoretical estimates are compared with experiments performed with MUMPS using the nested-dissection algorithm for construction of the elimination tree from METIS library. The numerical experiments provide the same performance for the cases where our trees are identical with those constructed by the nested-dissection algorithm, and worse performance for some cases where our trees are different. We also present numerical experiments for the cases with mixed singularities, where how to construct optimal elimination trees is unknown. In all analysed cases, the use of hh-adaptive grids significantly reduces the cost of the direct solver algorithm per unknown as compared to uniform grids. The theoretical estimates predict and the experimental data confirm that the computational complexity is linear for various refinement patterns. In most cases, the cost of the direct solver per unknown is lower when employing anisotropic refinements as opposed to isotropic ones.

  2. A Survey of Solver-Related Geometry and Meshing Issues

    Science.gov (United States)

    Masters, James; Daniel, Derick; Gudenkauf, Jared; Hine, David; Sideroff, Chris

    2016-01-01

    There is a concern in the computational fluid dynamics community that mesh generation is a significant bottleneck in the CFD workflow. This is one of several papers that will help set the stage for a moderated panel discussion addressing this issue. Although certain general "rules of thumb" and a priori mesh metrics can be used to ensure that some base level of mesh quality is achieved, inadequate consideration is often given to the type of solver or particular flow regime on which the mesh will be utilized. This paper explores how an analyst may want to think differently about a mesh based on considerations such as if a flow is compressible vs. incompressible or hypersonic vs. subsonic or if the solver is node-centered vs. cell-centered. This paper is a high-level investigation intended to provide general insight into how considering the nature of the solver or flow when performing mesh generation has the potential to increase the accuracy and/or robustness of the solution and drive the mesh generation process to a state where it is no longer a hindrance to the analysis process.

  3. Direct solvers performance on h-adapted grids

    KAUST Repository

    Paszynski, Maciej

    2015-05-27

    We analyse the performance of direct solvers when applied to a system of linear equations arising from an hh-adapted, C0C0 finite element space. Theoretical estimates are derived for typical hh-refinement patterns arising as a result of a point, edge, or face singularity as well as boundary layers. They are based on the elimination trees constructed specifically for the considered grids. Theoretical estimates are compared with experiments performed with MUMPS using the nested-dissection algorithm for construction of the elimination tree from METIS library. The numerical experiments provide the same performance for the cases where our trees are identical with those constructed by the nested-dissection algorithm, and worse performance for some cases where our trees are different. We also present numerical experiments for the cases with mixed singularities, where how to construct optimal elimination trees is unknown. In all analysed cases, the use of hh-adaptive grids significantly reduces the cost of the direct solver algorithm per unknown as compared to uniform grids. The theoretical estimates predict and the experimental data confirm that the computational complexity is linear for various refinement patterns. In most cases, the cost of the direct solver per unknown is lower when employing anisotropic refinements as opposed to isotropic ones.

  4. Legal nature of affatomia

    Directory of Open Access Journals (Sweden)

    Stanković Miloš

    2015-01-01

    Full Text Available In Salian and Ripuarian Code affatomia represented a bilateral legal transaction that was aimed at changing of the scoped of heirs determined by the customs, at least insofar being applied in the absence of biological descendants only. However, almost all further similarities in the field cease at this point. The form for using affatomia with Ripuarian Franks was much simpler than the one with the Salian Franks. Unlike the Salian Franks, affatomia could by all odds be used by Ripuarian Franks spouses in determining each other for a heir. Legal nature of the Salian Franks affatomia is most similar to the mancipatio familiae type of will in the Roman law (which does not mean it emerged from this law, while its form in the Ripuarian Code is much closer to testamentary adoption. As with Ripuarian Franks, affatomia seems to have definitely produced legal effects only after the death of the disposant, while its legal effects with the Salian Code performed inter vivos. Contemporary authors are trying to designate the legal nature of legal affairs from the early development of human and legal civilization through modern institutes that represent the completion of their evolutionary path. Taking the inheritance contract of the German or Swiss law, or the future assets donation of the French law, for example, and then comparing them to affatomia and thinx is an anachronism. This is evident by the fact that the legal nature of these ancient Germanic institutes can not be viewed unilaterally, but always through a combination of those institutes which we know today as adoption, gift or mixed donation with retention of different modalities for the transferor or the testator (usually usufruct. In this sense, if we are looking for a inheritance agreement in the Middle Ages, the contract in which a person determines other person for his/her universal or singular successor in the modern sense, we will certainly not find one. However, if within this institute we

  5. Adaptive multi-resolution 3D Hartree-Fock-Bogoliubov solver for nuclear structure

    Science.gov (United States)

    Pei, J. C.; Fann, G. I.; Harrison, R. J.; Nazarewicz, W.; Shi, Yue; Thornton, S.

    2014-08-01

    Background: Complex many-body systems, such as triaxial and reflection-asymmetric nuclei, weakly bound halo states, cluster configurations, nuclear fragments produced in heavy-ion fusion reactions, cold Fermi gases, and pasta phases in neutron star crust, are all characterized by large sizes and complex topologies in which many geometrical symmetries characteristic of ground-state configurations are broken. A tool of choice to study such complex forms of matter is an adaptive multi-resolution wavelet analysis. This method has generated much excitement since it provides a common framework linking many diversified methodologies across different fields, including signal processing, data compression, harmonic analysis and operator theory, fractals, and quantum field theory. Purpose: To describe complex superfluid many-fermion systems, we introduce an adaptive pseudospectral method for solving self-consistent equations of nuclear density functional theory in three dimensions, without symmetry restrictions. Methods: The numerical method is based on the multi-resolution and computational harmonic analysis techniques with a multi-wavelet basis. The application of state-of-the-art parallel programming techniques include sophisticated object-oriented templates which parse the high-level code into distributed parallel tasks with a multi-thread task queue scheduler for each multi-core node. The internode communications are asynchronous. The algorithm is variational and is capable of solving coupled complex-geometric systems of equations adaptively, with functional and boundary constraints, in a finite spatial domain of very large size, limited by existing parallel computer memory. For smooth functions, user-defined finite precision is guaranteed. Results: The new adaptive multi-resolution Hartree-Fock-Bogoliubov (HFB) solver madness-hfb is benchmarked against a two-dimensional coordinate-space solver hfb-ax that is based on the B-spline technique and a three-dimensional solver

  6. The risk to be tolerated and the limits of practical rationality - problems involved in nuclear licensing. - Are there prerogatives of the administration in decision-making. Fundamental criticism of the undefined legal concept in the law pertaining to plant licinsing

    International Nuclear Information System (INIS)

    Wolf, R.

    1986-01-01

    This chapter discusses in detail the litigation and court decisions in nuclear energy matters, with particular attention being given to the scope and distinctness of juristic interpretations of vaguely defined legal concepts, and to the definition of the 'risk to be tolerated'. Especially the court decisions on the nuclear power plant licences for the installations at Wuergassen, Wyhl, Grafenrheinfeld and Kalkar are reviewed under the following aspects: How safe is safe enough - bursting resistance - risk prevention and practical rationality - limits of scientific research into risk probability - fundamental criticism to be raised against vaguely defined legal terms and concepts in the law governing the licensing of nuclear installations. (HSCH) [de

  7. Java Based Symbolic Circuit Solver For Electrical Engineering Curriculum

    Directory of Open Access Journals (Sweden)

    Ruba Akram Amarin

    2012-11-01

    Full Text Available The interactive technical electronic book, TechEBook, currently under development at the University of Central Florida (UCF, introduces a paradigm shift by replacing the traditional electrical engineering course with topic-driven modules that provide a useful tool for engineers and scientists. The TechEBook comprises the two worlds of classical circuit books and interactive operating platforms such as iPads, laptops and desktops. The TechEBook provides an interactive applets screen that holds many modules, each of which has a specific application in the self learning process. This paper describes one of the interactive techniques in the TechEBook known as Symbolic Circuit Solver (SymCirc. The SymCirc develops a versatile symbolic based linear circuit with a switches solver. The solver works by accepting a Netlist and the element that the user wants to find the voltage across or current on, as input parameters. Then it either produces the plot or the time domain expression of the output. Frequency domain plots or Symbolic Transfer Functions are also produced. The solver gets its input from a Web-based GUI circuit drawer developed at UCF. Typical simulation tools that electrical engineers encounter are numerical in nature, that is, when presented with an input circuit they iteratively solve the circuit across a set of small time steps. The result is represented as a data set of output versus time, which can be plotted for further inspection. Such results do not help users understand the ultimate nature of circuits as Linear Time Invariant systems with a finite dimensional basis in the solution space. SymCirc provides all simulation results as time domain expressions composed of the basic functions that exclusively include exponentials, sines, cosines and/or t raised to any power. This paper explains the motivation behind SymCirc, the Graphical User Interface front end and how the solver actually works. The paper also presents some examples and

  8. An AMR capable finite element diffusion solver for ALE hydrocodes [An AMR capable diffusion solver for ALE-AMR

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, A. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bailey, D. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kaiser, T. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Eder, D. C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gunney, B. T. N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Masters, N. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Koniges, A. E. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Anderson, R. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-02-01

    Here, we present a novel method for the solution of the diffusion equation on a composite AMR mesh. This approach is suitable for including diffusion based physics modules to hydrocodes that support ALE and AMR capabilities. To illustrate, we proffer our implementations of diffusion based radiation transport and heat conduction in a hydrocode called ALE-AMR. Numerical experiments conducted with the diffusion solver and associated physics packages yield 2nd order convergence in the L2 norm.

  9. Environmental, legal and managerial aspects

    International Nuclear Information System (INIS)

    1978-09-01

    This U.S. contribution to the syllabus for Subgroup 5C treats with environmental and ecological aspects specific to fast breeder reactors, physical protection and safeguarding of the FBR cycle, fuel cycle centers (site selection problems for different degrees of collocation) and administrative and legal problems. Decommissioning of an FBR power plant, syllabus item C.1.7, is treated in separate contribution, more information on advanced safeguards for the fast breeder fyel cycle is contained in the contribution, USA WG 5C-tbd. A key conclusion of this is that with safeguards planning initiated early in the development of the FBR fuel cycle, time is available to develop, evaluate, and implement improved safeguards techniques and incorporate them into the design phase of all FBR cycle facilities

  10. The legal status of engineering companies

    International Nuclear Information System (INIS)

    1981-10-01

    It is assumed that the carrying out of research, also in the nuclear field should be entrusted to engineering companies, especially when dealing with the setting up of technological structures. This paper considers the problems of the legal status of such companies under Italian legislation. (NEA) [fr

  11. Development of an international matrix-solver prediction system on a French-Japanese international grid computing environment

    International Nuclear Information System (INIS)

    Suzuki, Yoshio; Kushida, Noriyuki; Tatekawa, Takayuki; Teshima, Naoya; Caniou, Yves; Guivarch, Ronan; Dayde, Michel; Ramet, Pierre

    2010-01-01

    The 'Research and Development of International Matrix-Solver Prediction System (REDIMPS)' project aimed at improving the TLSE sparse linear algebra expert website by establishing an international grid computing environment between Japan and France. To help users in identifying the best solver or sparse linear algebra tool for their problems, we have developed an interoperable environment between French and Japanese grid infrastructures (respectively managed by DIET and AEGIS). Two main issues were considered. The first issue is how to submit a job from DIET to AEGIS. The second issue is how to bridge the difference of security between DIET and AEGIS. To overcome these issues, we developed APIs to communicate between different grid infrastructures by improving the client API of AEGIS. By developing a server deamon program (SeD) of DIET which behaves like an AEGIS user, DIET can call functions in AEGIS: authentication, file transfer, job submission, and so on. To intensify the security, we also developed functionalities to authenticate DIET sites and DIET users in order to access AEGIS computing resources. By this study, the set of software and computers available within TLSE to find an appropriate solver is enlarged over France (DIET) and Japan (AEGIS). (author)

  12. Radiographic investigations during medico-legal autopsies

    Energy Technology Data Exchange (ETDEWEB)

    Bratzke, H.; Schneider, V.; Dietz, W.

    1982-04-01

    During the last 13 years (1968-1980), 427 radiographic examinations were carried out during the course of medico-legal autopsies at the Institute of Forensic Medicine at the Free University of Berlin. Important problems were the demonstration of retained foreign bodies resulting from shooting, stabbing or blunt trauma, bone injuries, identification, and the question of life in neonates. An historical survey is given and 12 cases with special forensic problems are illustrated and discussed, and further means of investigations are described.

  13. Discrimination of legal entities: Phenomenological characteristics and legal protection

    Directory of Open Access Journals (Sweden)

    Petrušić Nevena

    2017-01-01

    Full Text Available Their social nature encourages people to associate and jointly achieve the goals that they would not be able to achieve individually. Legal entities are created as one of the legal modalities of that association, as separate entities that have their own legal personality independent of the subjectivity of their members. Legal entities are holders of some human rights, depending on the nature of the right, including the right to non-discrimination. All mechanisms envisaged for legal protection against discrimination in the national legislation are available to legal persons. On the other hand, the situation is quite different in terms of access to international forums competent to deal with cases of discrimination. Legal entities do not have access to some international forums, while they may have access to others under the same conditions prescribed for natural persons. Legal entities may be exposed to various forms of direct and indirect discrimination both in the private and in the public sphere of social relations. Phenomenological characteristics of discrimination against legal persons are not substantially different from discrimination against individuals. There are no significant differences regarding the application of discrimination test in cases of discrimination of legal entities as compared to the use of this test in cases involving discrimination of natural persons or groups of persons. Legal entities may be discriminated against on the basis of characteristics of their legal personality, such as those which are objective elements of the legal entity and part of its legal identity. Discrimination of legal entities may be based on personal characteristics of its members (i.e. people who make a personal essence of a legal entity because their characteristics can be 'transferred' to the legal entity and become part of its identity. Legal entities should also be protected from this special form of transferred (associative discrimination.

  14. Numerical simulations of coupled problems in engineering

    CERN Document Server

    2014-01-01

    This book presents and discusses mathematical models, numerical methods and computational techniques used for solving coupled problems in science and engineering. It takes a step forward in the formulation and solution of real-life problems with a multidisciplinary vision, accounting for all of the complex couplings involved in the physical description. Simulation of multifaceted physics problems is a common task in applied research and industry. Often a suitable solver is built by connecting together several single-aspect solvers into a network. In this book, research in various fields was selected for consideration: adaptive methodology for multi-physics solvers, multi-physics phenomena and coupled-field solutions, leading to computationally intensive structural analysis. The strategies which are used to keep these problems computationally affordable are of special interest, and make this an essential book.

  15. New sparse matrix solver in the KIKO3D 3-dimensional reactor dynamics code

    International Nuclear Information System (INIS)

    Panka, I.; Kereszturi, A.; Hegedus, C.

    2005-01-01

    The goal of this paper is to present a more effective method Bi-CGSTAB for accelerating the large sparse matrix equation solution in the KIKO3D code. This equation system is obtained by using the factorization of the improved quasi static (IQS) method for the time dependent nodal kinetic equations. In the old methodology standard large sparse matrix techniques were considered, where Gauss-Seidel preconditioning and a GMRES-type solver were applied. The validation of KIKO3D using Bi-CGSTAB has been performed by solving of a VVER-1000 kinetic benchmark problem. Additionally, the convergence characteristics were investigated in given macro time steps of Control Rod Ejection transients. The results have been obtained by the old GMRES and new Bi-CGSTAB methods are compared. (author)

  16. PetClaw: A scalable parallel nonlinear wave propagation solver for Python

    KAUST Repository

    Alghamdi, Amal; Ahmadia, Aron; Ketcheson, David I.; Knepley, Matthew; Mandli, Kyle; Dalcin, Lisandro

    2011-01-01

    We present PetClaw, a scalable distributed-memory solver for time-dependent nonlinear wave propagation. PetClaw unifies two well-known scientific computing packages, Clawpack and PETSc, using Python interfaces into both. We rely on Clawpack to provide the infrastructure and kernels for time-dependent nonlinear wave propagation. Similarly, we rely on PETSc to manage distributed data arrays and the communication between them.We describe both the implementation and performance of PetClaw as well as our challenges and accomplishments in scaling a Python-based code to tens of thousands of cores on the BlueGene/P architecture. The capabilities of PetClaw are demonstrated through application to a novel problem involving elastic waves in a heterogeneous medium. Very finely resolved simulations are used to demonstrate the suppression of shock formation in this system.

  17. PyOperators: Operators and solvers for high-performance computing

    Science.gov (United States)

    Chanial, P.; Barbey, N.

    2012-12-01

    PyOperators is a publicly available library that provides basic operators and solvers for small-to-very large inverse problems ({http://pchanial.github.com/pyoperators}). It forms the backbone of the package PySimulators, which implements specific operators to construct an instrument model and means to conveniently represent a map, a timeline or a time-dependent observation ({http://pchanial.github.com/pysimulators}). Both are part of the Tamasis (Tools for Advanced Map-making, Analysis and SImulations of Submillimeter surveys) toolbox, aiming at providing versatile, reliable, easy-to-use, and optimal map-making tools for Herschel and future generation of sub-mm instruments. The project is a collaboration between 4 institutes (ESO Garching, IAS Orsay, CEA Saclay, Univ. Leiden).

  18. Highly efficient parallel direct solver for solving dense complex matrix equations from method of moments

    Directory of Open Access Journals (Sweden)

    Yan Chen

    2017-03-01

    Full Text Available Based on the vectorised and cache optimised kernel, a parallel lower upper decomposition with a novel communication avoiding pivoting scheme is developed to solve dense complex matrix equations generated by the method of moments. The fine-grain data rearrangement and assembler instructions are adopted to reduce memory accessing times and improve CPU cache utilisation, which also facilitate vectorisation of the code. Through grouping processes in a binary tree, a parallel pivoting scheme is designed to optimise the communication pattern and thus reduces the solving time of the proposed solver. Two large electromagnetic radiation problems are solved on two supercomputers, respectively, and the numerical results demonstrate that the proposed method outperforms those in open source and commercial libraries.

  19. Society as a crime victim of legal entities

    Directory of Open Access Journals (Sweden)

    Tanjević Nataša

    2011-01-01

    Full Text Available Tortious acts of legal entities have unforeseen harmful consequences in all areas. In the greedy desire to gain profit, certain legal entities do not have any regard for the most important resources of individuals and society. Damage resulting from the commission of criminal acts is very high for the whole society, especially when it comes to crimes against the environment. In order to prevent and combat corporate crime in criminal law, an increasingly wider acceptance of criminal liability of legal entities was adopted. This paper discusses the basic characteristics of corporate crime, as well as the reasons for the introduction of the criminal responsibility of legal entities. In this regard, we analyzed the law provisions regarding the liability of legal entities for criminal offenses, and concluded that despite the criminal-political need to react with more serious sanctions to the offenses of legal entities, there are certain obstacles and problems that stand in the way of introducing this responsibility.

  20. IRMHD: an implicit radiative and magnetohydrodynamical solver for self-gravitating systems

    Science.gov (United States)

    Hujeirat, A.

    1998-07-01

    The 2D implicit hydrodynamical solver developed by Hujeirat & Rannacher is now modified to include the effects of radiation, magnetic fields and self-gravity in different geometries. The underlying numerical concept is based on the operator splitting approach, and the resulting 2D matrices are inverted using different efficient preconditionings such as ADI (alternating direction implicit), the approximate factorization method and Line-Gauss-Seidel or similar iteration procedures. Second-order finite volume with third-order upwinding and second-order time discretization is used. To speed up convergence and enhance efficiency we have incorporated an adaptive time-step control and monotonic multilevel grid distributions as well as vectorizing the code. Test calculations had shown that it requires only 38 per cent more computational effort than its explicit counterpart, whereas its range of application to astrophysical problems is much larger. For example, strongly time-dependent, quasi-stationary and steady-state solutions for the set of Euler and Navier-Stokes equations can now be sought on a non-linearly distributed and strongly stretched mesh. As most of the numerical techniques used to build up this algorithm have been described by Hujeirat & Rannacher in an earlier paper, we focus in this paper on the inclusion of self-gravity, radiation and magnetic fields. Strategies for satisfying the condition ∇.B=0 in the implicit evolution of MHD flows are given. A new discretization strategy for the vector potential which allows alternating use of the direct method is prescribed. We investigate the efficiencies of several 2D solvers for a Poisson-like equation and compare their convergence rates. We provide a splitting approach for the radiative flux within the FLD (flux-limited diffusion) approximation to enhance consistency and accuracy between regions of different optical depths. The results of some test problems are presented to demonstrate the accuracy and

  1. Simplified Eigen-structure decomposition solver for the simulation of two-phase flow systems

    International Nuclear Information System (INIS)

    Kumbaro, Anela

    2012-01-01

    This paper discusses the development of a new solver for a system of first-order non-linear differential equations that model the dynamics of compressible two-phase flow. The solver presents a lower-complexity alternative to Roe-type solvers because it only makes use of a partial Eigen-structure information while maintaining its accuracy: the outcome is hence a good complexity-tractability trade-off to consider as relevant in a large number of situations in the scope of two-phase flow numerical simulation. A number of numerical and physical benchmarks are presented to assess the solver. Comparison between the computational results from the simplified Eigen-structure decomposition solver and the conventional Roe-type solver gives insight upon the issues of accuracy, robustness and efficiency. (authors)

  2. Commission on Legal Matters

    CERN Multimedia

    Staff Association

    2016-01-01

    What is a commission within the Staff Association (SA)? A commission is a working group of the CERN Staff Council, led by a staff representative. The commission is composed mainly of staff representatives, but interested members of the SA can apply to participate in the work of a commission. What is the commission on legal matters? The commission on legal matters works on texts governing the employment conditions of staff (Employed Members of Personnel and Associated Members of Personnel). This covers legal documents such as the Staff Rules and Regulations, administrative and operational circulars, as well as any other document relating to employment conditions. How is the work organised in this commission? The revision process of the text is generally done along following lines: The HR department, and its legal experts, proposes new texts or modifications to existing texts. A schedule for the study of these texts is established each year and this calendar by the commission to plan its work. The new or modi...

  3. Minimally legally invasive dentistry.

    Science.gov (United States)

    Lam, R

    2014-12-01

    One disadvantage of the rapid advances in modern dentistry is that treatment options have never been more varied or confusing. Compounded by a more educated population greatly assisted by online information in an increasingly litigious society, a major concern in recent times is increased litigation against health practitioners. The manner in which courts handle disputes is ambiguous and what is considered fair or just may not be reflected in the judicial process. Although legal decisions in Australia follow a doctrine of precedent, the law is not static and is often reflected by community sentiment. In medical litigation, this has seen the rejection of the Bolam principle with a preference towards greater patient rights. Recent court decisions may change the practice of dentistry and it is important that the clinician is not caught unaware. The aim of this article is to discuss legal issues that are pertinent to the practice of modern dentistry through an analysis of legal cases that have shaped health law. Through these discussions, the importance of continuing professional development, professional association and informed consent will be realized as a means to limit the legal complications of dental practice. © 2014 Australian Dental Association.

  4. Euthanasia: Some Legal Considerations

    Science.gov (United States)

    Koza, Pamela

    1976-01-01

    Several sections of the Criminal Code of Canada which are relevant to the issue of euthanasia are discussed. In addition, the value placed on the sanctity of life by the law, the failure to recognize motive in cases of euthanasia, and disparate legal and medical definitions of death are also considered. (Author)

  5. Defeasibility in Legal Reasoning

    OpenAIRE

    SARTOR, Giovanni

    2009-01-01

    I shall first introduce the idea of reasoning, and of defeasible reasoning in particular. I shall then argue that cognitive agents need to engage in defeasible reasoning for coping with a complex and changing environment. Consequently, defeasibility is needed in practical reasoning, and in particular in legal reasoning

  6. Documents and legal texts

    International Nuclear Information System (INIS)

    2017-01-01

    This section treats of the following documents and legal texts: 1 - Belgium 29 June 2014 - Act amending the Act of 22 July 1985 on Third-Party Liability in the Field of Nuclear Energy; 2 - Belgium, 7 December 2016. - Act amending the Act of 22 July 1985 on Third-Party Liability in the Field of Nuclear Energy

  7. Using Solver Interfaced Virtual Reality in PEACER Design Process

    International Nuclear Information System (INIS)

    Lee, Hyong Won; Nam, Won Chang; Jeong, Seung Ho; Hwang, Il Soon; Shin, Jong Gye; Kim, Chang Hyo

    2006-01-01

    The recent research progress in the area of plant design and simulation highlighted the importance of integrating design and analysis models on a unified environment. For currently developed advanced reactors, either for power production or research, this effort has embraced impressive state-of-the-art information and automation technology. The PEACER (Proliferation-resistant, Environment friendly, Accident-tolerant, Continual and Economical Reactor) is one of the conceptual fast reactor system cooled by LBE (Lead Bismuth Eutectic) for nuclear waste transmutation. This reactor system is composed of innovative combination between design process and analysis. To establish an integrated design process by coupling design, analysis, and post-processing technology while minimizing the repetitive and costly manual interactions for design changes, a solver interfaced virtual reality simulation system (SIVR) has been developed for a nuclear transmutation energy system as PEACER. The SIVR was developed using Virtual Reality Modeling Language (VRML) in order to interface a commercial 3D CAD tool with various engineering solvers and to implement virtual reality presentation of results in a neutral format. In this paper, we have shown the SIVR approach viable and effective in the life-cycle management of complex nuclear energy systems, including design, construction and operation. For instance, The HELIOS is a down scaled model of the PEACER prototype to demonstrate the operability and safety as well as preliminary test of PEACER PLM (Product Life-cycle Management) with SIVR (Solver Interfaced Virtual Reality) concepts. Most components are designed by CATIA, which is 3D CAD tool. During the construction, 3D drawing by CATIA was effective to handle and arrange the loop configuration, especially when we changed the design. Most of all, This system shows the transparency of design and operational status of an energy complex to operators and inspectors can help ensure accident

  8. Application of Nearly Linear Solvers to Electric Power System Computation

    Science.gov (United States)

    Grant, Lisa L.

    To meet the future needs of the electric power system, improvements need to be made in the areas of power system algorithms, simulation, and modeling, specifically to achieve a time frame that is useful to industry. If power system time-domain simulations could run in real-time, then system operators would have situational awareness to implement online control and avoid cascading failures, significantly improving power system reliability. Several power system applications rely on the solution of a very large linear system. As the demands on power systems continue to grow, there is a greater computational complexity involved in solving these large linear systems within reasonable time. This project expands on the current work in fast linear solvers, developed for solving symmetric and diagonally dominant linear systems, in order to produce power system specific methods that can be solved in nearly-linear run times. The work explores a new theoretical method that is based on ideas in graph theory and combinatorics. The technique builds a chain of progressively smaller approximate systems with preconditioners based on the system's low stretch spanning tree. The method is compared to traditional linear solvers and shown to reduce the time and iterations required for an accurate solution, especially as the system size increases. A simulation validation is performed, comparing the solution capabilities of the chain method to LU factorization, which is the standard linear solver for power flow. The chain method was successfully demonstrated to produce accurate solutions for power flow simulation on a number of IEEE test cases, and a discussion on how to further improve the method's speed and accuracy is included.

  9. Computational aeroelasticity using a pressure-based solver

    Science.gov (United States)

    Kamakoti, Ramji

    A computational methodology for performing fluid-structure interaction computations for three-dimensional elastic wing geometries is presented. The flow solver used is based on an unsteady Reynolds-Averaged Navier-Stokes (RANS) model. A well validated k-ε turbulence model with wall function treatment for near wall region was used to perform turbulent flow calculations. Relative merits of alternative flow solvers were investigated. The predictor-corrector-based Pressure Implicit Splitting of Operators (PISO) algorithm was found to be computationally economic for unsteady flow computations. Wing structure was modeled using Bernoulli-Euler beam theory. A fully implicit time-marching scheme (using the Newmark integration method) was used to integrate the equations of motion for structure. Bilinear interpolation and linear extrapolation techniques were used to transfer necessary information between fluid and structure solvers. Geometry deformation was accounted for by using a moving boundary module. The moving grid capability was based on a master/slave concept and transfinite interpolation techniques. Since computations were performed on a moving mesh system, the geometric conservation law must be preserved. This is achieved by appropriately evaluating the Jacobian values associated with each cell. Accurate computation of contravariant velocities for unsteady flows using the momentum interpolation method on collocated, curvilinear grids was also addressed. Flutter computations were performed for the AGARD 445.6 wing at subsonic, transonic and supersonic Mach numbers. Unsteady computations were performed at various dynamic pressures to predict the flutter boundary. Results showed favorable agreement of experiment and previous numerical results. The computational methodology exhibited capabilities to predict both qualitative and quantitative features of aeroelasticity.

  10. The Effect of Learning Environments Based on Problem Solving on Students' Achievements of Problem Solving

    Science.gov (United States)

    Karatas, Ilhan; Baki, Adnan

    2013-01-01

    Problem solving is recognized as an important life skill involving a range of processes including analyzing, interpreting, reasoning, predicting, evaluating and reflecting. For that reason educating students as efficient problem solvers is an important role of mathematics education. Problem solving skill is the centre of mathematics curriculum.…

  11. Legal and Administrative Problems of Controlling the Disposal of Nuclear Wastes in the Sea; Problemes Juridiques et Administratifs Poses par le Controle de l'Elimination des Dechets Nucleaires dans la Mer; 041f 0420 041e 0414 ; Problemas Juridicos y Administrativos que Plantea el Control de la Evacuacion de Desechos Nucleares En El Mar

    Energy Technology Data Exchange (ETDEWEB)

    Hydeman, Lee M.; Berman, William H. [Atomic Energy Research Project, University of Michigan Law School (United States)

    1960-07-01

    The basic purpose of the paper is to present some approaches to multinational control of the sea disposal of nuclear wastes, considering both the type of international .control which may be appropriate and the means for accomplishing such control. First, the authors give a brief description of the kind of control which appears to be necessary in protecting public health against the hazards of the disposal of wastes in the sea. The second part consists of a general analysis of the legal problems posed by nuclear wastes. Emphasis is placed on the authority of coastal states to impose unilateral control on the disposal of wastes by other nations if such disposal might adversely affect their interests. The authors inquire into the adequacy of legal remedies as well as the possible rule of law regarding the prevention of damage from waste disposal and the apportionment of liability in the event that such damage does occur. The third part is an analysis of how other problems of control have been handled, both unilaterally and multilaterally. The final part consists of an inquiry into various means of internationally controlling the sea disposal of nuclear wastes. The role of existing international bodies in the maintenance of continuing administrative control at the international level is mentioned. (author) [French] Le but essentiel du memoire est d'exposer diverses facons d'envisager le probleme du controle multinational de l'evacuation des dechets nucleaires dans l'eau de mer, en examinant a la fois le type de controle international approprie et les moyens de le mettre en oeuvre. La premiere partie contiendra une description succincte du genre de controle qui semble necessaire pour la protection de la sante publique contre les effets de l'evacuation des dechets dans la mer. La deuxieme partie consistera en une analyse generale des problemes juridiques poses par. l'elimination des dechets nucleaires. Les auteurs traiteront particulierement du droit des Etats riverains

  12. SCALE--A Conceptual and Transactional Method of Legal Study.

    Science.gov (United States)

    Johnson, Darrell B.

    1985-01-01

    Southwestern University School of Law's two-year, intensive, year-round program, the Southwestern Conceptual Approach to Legal Education, which emphasizes hypothetical problems as teaching tools rather than the case-book method, is described. (MSE)

  13. Modeling Microbunching from Shot Noise Using Vlasov Solvers

    International Nuclear Information System (INIS)

    Venturini, Marco; Venturini, Marco; Zholents, Alexander

    2008-01-01

    Unlike macroparticle simulations, which are sensitive to unphysical statistical fluctuations when the number of macroparticles is smaller than the bunch population, direct methods for solving the Vlasov equation are free from sampling noise and are ideally suited for studying microbunching instabilities evolving from shot noise. We review a 2D (longitudinal dynamics) Vlasov solver we have recently developed to study the microbunching instability in the beam delivery systems for x-ray FELs and present an application to FERMI(at)Elettra. We discuss, in particular, the impact of the spreader design on microbunching

  14. Parallel implementations of 2D explicit Euler solvers

    International Nuclear Information System (INIS)

    Giraud, L.; Manzini, G.

    1996-01-01

    In this work we present a subdomain partitioning strategy applied to an explicit high-resolution Euler solver. We describe the design of a portable parallel multi-domain code suitable for parallel environments. We present several implementations on a representative range of MlMD computers that include shared memory multiprocessors, distributed virtual shared memory computers, as well as networks of workstations. Computational results are given to illustrate the efficiency, the scalability, and the limitations of the different approaches. We discuss also the effect of the communication protocol on the optimal domain partitioning strategy for the distributed memory computers

  15. CHILD LABOR ABUSE: LEGAL ASPECTS

    Directory of Open Access Journals (Sweden)

    Darko Majhoshev

    2016-01-01

    Full Text Available The paper addresses the problem of child labor and ways of protection from child labor abuse. Child labor is a negative social phenomenon that is widespread throughout the world, and also in Republic of Macedonia. International and national institutions and organizations are making serious efforts to eradicate this negative phenomenon, through the adoption of numerous international legal instruments (conventions, recommendations, declarations, etc.. Child labor as a phenomenon refers to the employment of children in any work that deprives children of their childhood, interferes with their ability of education, and that is socially, mentally, physically, or morally dangerous and harmful. All international organizations define this practice as exploitative and destructive to the development of the whole society. With international legal instruments of the UN, ILO, Council of Europe and the EU child labor is strictly prohibited. There are some important differences which exist between the many kinds of work that is done by children. Some of them are demanding and difficult, others are hazardous and morally reprehensible. Children are doing a very wide range of activities and tasks when they work.

  16. Modern Questions Of The Legal Philosophy

    Directory of Open Access Journals (Sweden)

    Gennadiy A. Torgashev

    2014-06-01

    Full Text Available In the present article author considers fundamental problems of law connected with equality, justice and freedom. Author proves that philosophy and law as forms of public consciousness carry out the important closely interconnected among themselves functions of the social life judgment. In the article author noted that among other forms of public consciousness law is one of difficult objects of knowledge, because law is connected with such forms of consciousness as philosophy, morals, religion, policy. The legal philosophy is the philosophical discipline having the subject the general regularities of law functioning, taken in their historical and sociocultural development, definition and the sense of legal judgment and its fundamental concepts. Law represents a set of obligatory rules of conduct (norms established by the authorized or the state. Diverse spiritual life of the society assumes a variety in the nature of law. The typology of philosophical concepts of the law and how the legal philosophy interprets legal reality is researched, various philosophical and legal concepts which are caused by two main types of rights – natural and positive are allocated. Author gives opinions of scientists, and explains own views of the author.

  17. On the implicit density based OpenFOAM solver for turbulent compressible flows

    Science.gov (United States)

    Fürst, Jiří

    The contribution deals with the development of coupled implicit density based solver for compressible flows in the framework of open source package OpenFOAM. However the standard distribution of OpenFOAM contains several ready-made segregated solvers for compressible flows, the performance of those solvers is rather week in the case of transonic flows. Therefore we extend the work of Shen [15] and we develop an implicit semi-coupled solver. The main flow field variables are updated using lower-upper symmetric Gauss-Seidel method (LU-SGS) whereas the turbulence model variables are updated using implicit Euler method.

  18. Integrating Multimedia and Physics Problems

    Science.gov (United States)

    Titus, Aaron P.

    1997-11-01

    Although expert problem solvers typically use pictorial representations when solving problems, novices tend to proceed from the given problem statement to a mathematical solution without first developing a visual representation of the problem. For this reason, multimedia may be an effective tool to enhance students' success at solving problems. However, merely presenting a video of motion described in a problem is not necessarily the most effective method as was found in a recent study of students' responses on Web-based homework questions. Rather, multimedia-focused problems, where data relevant to solving the problem is embedded in a video or animation, may be the best use of multimedia in problem solving. Examples of multimedia-enhanced problems and multimedia-focused problems will be demonstrated, and their differences from "traditional" problems will be highlighted. Recommendations on the use of multimedia with problem solving and preliminary data on students' success at solving these problems will be discussed.

  19. The quantum mechanics solver. How to apply quantum theory to modern physics. 2. ed.

    International Nuclear Information System (INIS)

    Basdevant, J.L.; Dalibard, J.

    2006-01-01

    The Quantum Mechanics Solver uniquely illustrates the application of quantum mechanical concepts to various fields of modern physics. It aims at encouraging the reader to apply quantum mechanics to research problems in fields such as molecular physics, condensed matter physics or laser physics. Advanced undergraduates and graduate students will find a rich and challenging source of material for further exploration. This book consists of a series of problems concerning present-day experimental or theoretical questions on quantum mechanics. All of these problems are based on actual physical examples, even if sometimes the mathematical structure of the models under consideration is simplified intentionally in order to get hold of the physics more rapidly. The new edition features new themes, such as the progress in measuring neutrino oscillations, quantum boxes, the quantum thermometer etc. Secondly, it includes a brief summary on the basics of quantum mechanics and the formalism we use. Finally, the problems under three main themes: Elementary Particles, Nuclei and Atoms; Quantum Entanglement and Measurement; and Complex Systems. (orig.)

  20. A vectorized Poisson solver over a spherical shell and its application to the quasi-geostrophic omega-equation

    Science.gov (United States)

    Mullenmeister, Paul

    1988-01-01

    The quasi-geostrophic omega-equation in flux form is developed as an example of a Poisson problem over a spherical shell. Solutions of this equation are obtained by applying a two-parameter Chebyshev solver in vector layout for CDC 200 series computers. The performance of this vectorized algorithm greatly exceeds the performance of its scalar analog. The algorithm generates solutions of the omega-equation which are compared with the omega fields calculated with the aid of the mass continuity equation.