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31.
Mickaël Duval Jean-Charles Passieux Michel Salaün Stéphane Guinard 《Archives of Computational Methods in Engineering》2016,23(1):17-38
This paper provides a detailed review of the global/local non-intrusive coupling algorithm. Such method allows to alter a global finite element model, without actually modifying its corresponding numerical operator. We also look into improvements of the initial algorithm (Quasi-Newton and dynamic relaxation), and provide comparisons based on several relevant test cases. Innovative examples and advanced applications of the non-intrusive coupling algorithm are provided, granting a handy framework for both researchers and engineers willing to make use of such process. Finally, a novel nonlinear domain decomposition method is derived from the global/local non-intrusive coupling strategy, without the need to use a parallel code or software. Such method being intended to large scale analysis, we show its scalability. Jointly, an efficient high level Message Passing Interface coupling framework is also proposed, granting an universal and flexible way for easy software coupling. A sample code is also given. 相似文献
32.
Geographic applications are often over-constrained because of the stakeholders’ multiple requirements and the various spatial, alphanumeric and temporal constraints to be satisfied. In most cases, solving over-constrained problems is based on the relaxation of some constraints according to values of preferences. This article proposes the modelling and the management of constraints in order to provide a framework to integrate stakeholders in the expression and the relaxation of their constraints. Three families of constraints are defined: static vs. dynamic, intra-entity vs. inter-entities and intra-instance vs. inter-instances. Constraints are modelled from two points of view: system with the complexity in time of the different involved operators and user with stakeholders’ preferences. The methodology of constraints relaxation is based on primitive, complex and derived operations. These operations allow a modification of the constraints in order to provide a relevant solution to a simulation. The developed system was applied to reduce the streaming/floods risks in the territory of Pays de Caux (Seine Maritime, France). 相似文献
33.
Hrachya Astsatryan Vladimir Sahakyan Yuri Shoukouryan Michel Daydé Aurelie Hurault Ronan Guivarch Harutyun Terzyan Levon Hovhannisyan 《Journal of Grid Computing》2013,11(2):239-248
Scientific research is becoming increasingly dependent on the large-scale analysis of data using distributed computing infrastructures (Grid, cloud, GPU, etc.). Scientific computing (Petitet et al. 1999) aims at constructing mathematical models and numerical solution techniques for solving problems arising in science and engineering. In this paper, we describe the services of an integrated portal based on the P-Grade (Parallel Grid Run-time and Application Development Environment) portal (http://www.p-grade.hu) that enables the solution of large-scale linear systems of equations using direct solvers, makes easier the use of parallel block iterative algorithm and provides an interface for parallel decision making algorithms. The ultimate goal is to develop a single sign on integrated multi-service environment providing an easy access to different kind of mathematical calculations and algorithms to be performed on hybrid distributed computing infrastructures combining the benefits of large clusters, Grid or cloud, when needed. 相似文献
34.
Let A be a set and let G be a group, and equip AG with its prodiscrete uniform structure. Let τ:AG→AG be a map. We prove that τ is a cellular automaton if and only if τ is uniformly continuous and G-equivariant. We also give an example showing that a continuous and G-equivariant map τ:AG→AG may fail to be a cellular automaton when the alphabet set A is infinite. 相似文献
35.
Mixtures of probabilistic principal component analyzers model high-dimensional nonlinear data by combining local linear models. Each mixture component is specifically designed to extract the local principal orientations in the data. An important issue with this generative model is its sensitivity to data lying off the low-dimensional manifold. In order to address this problem, the mixtures of robust probabilistic principal component analyzers are introduced. They take care of atypical points by means of a long tail distribution, the Student-t. It is shown that the resulting mixture model is an extension of the mixture of Gaussians, suitable for both robust clustering and dimensionality reduction. Finally, we briefly discuss how to construct a robust version of the closely related mixture of factor analyzers. 相似文献
36.
37.
Creep experiments were conducted on ice crystals in compression to investigate the effects of boundary conditions on a single-slip system deformed in plane strain. Friction at the platens of the deformation apparatus introduces a bending moment which causes a variation in the amount of lattice rotation across the specimen. This is shown to occur in mechanically constrained crystals observed through plane polarized light. Relieving the constraints and minimizing friction at the ice-platen contact leads to the widening of the sample near the specimen-platen interface and the production of tails symmetrically disposed about the longitudinal axis of the deformed crystals. This is interpreted to originate from a bending moment in the opposite sense from that obtained in the constrained crystals, resulting from a progressive increase in slip displacement towards the platens where the segments of the slip plane become shorter. When the crystal ends were constrained but allowed to move sideways, a simple shear regime was established in which lattice slip was concentrated in the centre of the crystal. 相似文献
38.
Wurster Marco Michel Marius May Marvin Carl Kuhnle Andreas Stricker Nicole Lanza Gisela 《Journal of Intelligent Manufacturing》2022,33(2):575-591
Journal of Intelligent Manufacturing - Remanufacturing includes disassembly and reassembly of used products to save natural resources and reduce emissions. While assembly is widely understood in... 相似文献
39.
We investigated whether, in rheumatoid arthritis (RA), the CD45 isoform expression of peripheral blood T-lymphocytes (T-PBL) is related to auto-immune processes (e.g. IgM rheumatoid factors) and to clinical manifestations. By three-colour flow cytometry, we quantified three subsets of CD4+ or CD8+ T-PBL: "naive" CD45RA+,RO-, "transient" CD45RA+,RO+, and "memory" CD45RA-,RO+ cells, in 102 patients with RA and in 41 age- and sex-matched controls. The serum levels of rheumatoid factors (RF) were determined--besides conventional agglutination tests--by ELISA (IgM-RF). Extensive clinical examination was performed at the time of blood sampling. In RA, age, sex and drug therapy did not constitute major influences on the CD45RA/RO patterns. In "healthy" men, higher age significantly' correlated with fewer naive and more memory CD4+ T-PBL (P < 0.01). In RA, distinct correlations between the T-PBL subsets, autoimmune and clinical manifestations became obvious when patients with low and high levels of RF against human IgG Fc fragments, as determined by ELISA, were analysed separately. RA patients with high IgM-RF had elevated proportions of CD45RO+ T-PBL (P < 0.05), that correlated with clinical parameters of disease activity (tender joint count, Ritchie index, P < 0.05) and outcome (Health Assessment Questionnaire, Larsen radiographic scores, P < 0.05). The proportions of memory CD4+ and CD8+ T-PBL correlated strongly (P < 0.001) with the IgM-RF levels. Within 1 year, only three of 34 patients (disease duration of 5-9 years) showed seroconversion from low to high levels of IgM-RF (and positive agglutination tests); this was paralleled by reductions in naive and increases in transient T-PBL (P < 0.02). Thus, in RA, the proportions of memory CD4+ and CD8+ T-PBL correlate with the level of IgM-RF and, together with transient T-PBL, with clinical parameters of disease activity and outcome. 相似文献
40.
Exploring the power of shared memory communication objects and models, and the limits of distributed computability are among the most exciting research areas of distributed computing. In that spirit, this paper focuses on a problem that has received considerable interest since its introduction in 1987, namely the renaming problem. It was the first non-trivial problem known to be solvable in an asynchronous distributed system despite process failures. Many algorithms for renaming and variants of renaming have been proposed, and sophisticated lower bounds have been proved, that have been a source of new ideas of general interest to distributed computing. It has consequently acquired a paradigm status in distributed fault-tolerant computing.In the renaming problem, processes start with unique initial names taken from a large name space, then deciding new names such that no two processes decide the same new name and the new names are from a name space that is as small as possible.This paper presents an introduction to the renaming problem in shared memory systems, for non-expert readers. It describes both algorithms and lower bounds. Also, it discusses strong connections relating renaming and other important distributed problems such as set agreement and symmetry breaking. 相似文献