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Contends that the ideal program of research to maximize clinical relevance combines 4 models of strategies. These are (1) convergent/convergent, (2) divergent/divergent, (3) divergent-theory/convergent-method, and (4) convergent-theory/divergent-method, and all are employed nomothetically at the level of theory and idiographically at the level of method. Model 1 serves to expand theoretical and procedural possibilities, giving clinicians the flexibility they need when working with individuals in service-delivery settings. Model 2 controls theoretical expansion. Model 3 controls procedural expansion. Model 4 may be used to provide preliminary demonstrations of feasibility that are then used to stimulate other forms of more directly relevant investigation. The products of this overall program of research will increasingly represent a useful body of tested theoretical and procedural possibilities and alternatives that clinicians can use for explaining and treating individual clients and for evaluating treatment outcomes in individually relevant terms. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Jibum Kim Thap Panitanarak Suzanne M. Shontz 《International journal for numerical methods in engineering》2013,94(1):20-42
We propose a multiobjective mesh optimization framework for mesh quality improvement and mesh untangling. Our framework combines two or more competing objective functions into a single objective function to be solved using one of various multiobjective optimization methods. Methods within our framework are able to optimize various aspects of the mesh such as the element shape, element size, associated PDE interpolation error, and number of inverted elements, but the improvement is not limited to these categories. The strength of our multiobjective mesh optimization framework lies in its ability to be extended to simultaneously optimize any aspects of the mesh and to optimize meshes with different element types. We propose the exponential sum, objective product, and equal sum multiobjective mesh optimization methods within our framework; these methods do not require articulation of preferences. However, the solutions obtained satisfy a sufficient condition of weak Pareto optimality. Experimental results show that our multiobjective mesh optimization methods are able to simultaneously optimize two or more aspects of the mesh and also are able to improve mesh qualities while eliminating inverted elements. We successfully apply our methods to real‐world applications such as hydrocephalus treatment and shape optimization. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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The development of parallel algorithms for mesh generation, untangling, and quality improvement is of high importance due to the need for large meshes with millions to billions of elements and the availability of supercomputers with hundreds to thousands of cores. There have been prior efforts in the development of parallel algorithms for mesh generation and local mesh quality improvement in which only one vertex is moved at a time. But for global mesh untangling and for global mesh quality improvement, where all vertices are simultaneously moved, parallel algorithms have not yet been developed. In our earlier work, we developed a serial global mesh optimization algorithm and used it to perform mesh untangling and mesh quality improvement. Our algorithm moved the vertices simultaneously to optimize a log-barrier objective function that was designed to untangle meshes as well as to improve the quality of the worst quality mesh elements. In this paper, we extend our work and develop a parallel log-barrier mesh untangling and mesh quality improvement algorithm for distributed-memory machines. We have used the algorithm with an edge coloring-based algorithm for synchronizing unstructured communication among the processes executing the log-barrier mesh optimization algorithm. The main contribution of this paper is a generic scheme for global mesh optimization, whereby the gradient of the objective function with respect to the position of some of the vertices is communicated among all processes in every iteration. The algorithm was implemented using the OpenMPI 2.0 parallel programming constructs and shows greater strong scaling efficiency compared to an existing parallel mesh quality improvement technique. 相似文献
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Shankar P. Sastry Emre Kultursay Suzanne M. Shontz Mahmut T. Kandemir 《Engineering with Computers》2014,30(4):535-547
Solving partial differential equations using finite element (FE) methods for unstructured meshes that contain billions of elements is computationally a very challenging task. While parallel implementations can deliver a solution in a reasonable amount of time, they suffer from low cache utilization due to unstructured data access patterns. In this work, we reorder the way the mesh vertices and elements are stored in memory using Hilbert space-filling curves to improve cache utilization in FE methods for unstructured meshes. This reordering technique enumerates the mesh elements such that parallel threads access shared vertices at different time intervals, reducing the time wasted waiting to acquire locks guarding atomic regions. Further, when the linear system resulting from the FE analysis is solved using the preconditioned conjugate gradient method, the performance of the block-Jacobi preconditioner also improves, as more nonzeros are present near the stiffness matrix diagonal. Our results show that our reordering reduces the L1 and L2 cache miss-rates in the stiffness matrix assembly step by about 50 and 10 %, respectively, on a single-core processor. We also reduce the number of iterations required to solve the linear system by about 5 %. Overall, our reordering reduces the time to assemble the stiffness matrix and to solve the linear system on a 4-socket, 48-core multi-processor by about 20 %. 相似文献
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Employed an experimental analog of interpersonal relationships presumed to exist in everyday life to test the ideas that alcoholics in treatment invite punishment from others by means of passive and aggressive behavior primarily when they do not have to assume responsibility. 20 alcoholics made significantly more mistakes on the prescribed task which resulted in their getting shocked more frequently than did the comparison group of 20 nonalcoholics. However, the alcoholics significantly avoided admitting mistakes when the acceptance of responsibility would eventuate in being shocked. Results have implications for the use of noxious stimuli as a method of modifying excessive drinking behavior. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Meresko Robert; Rubin Mandel; Shontz Franklin C.; Morrow William R. 《Canadian Metallurgical Quarterly》1954,49(1):89
"It was predicted that under present social conditions, urban American college students would show substantial individual consistency in the degree to which they manifest rigidity of attitudes regarding personal habits (hypothesis 1). Further, on the basis of previous research findings, it was predicted that rigidity of attitudes regarding personal habits would be significantly associated with acceptance of fascist or antidemocratic ideology (hypothesis 2)." The data are interpreted as supporting both hypotheses. 19 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We characterize the performance of gradient- and Hessian-based optimization methods for mesh quality improvement. In particular, we consider the steepest descent and Polack-Ribière conjugate gradient methods which are gradient based. In the Hessian-based category, we consider the quasi-Newton, trust region, and feasible Newton methods. These techniques are used to improve the quality of a mesh by repositioning the vertices, where the overall mesh quality is measured by the sum of the squares of individual elements according to the aspect ratio metric. The effects of the desired degree of accuracy in the improved mesh, problem size, initial mesh configuration, and heterogeneity in element volume on the performance of the optimization solvers are characterized on a series of tetrahedral meshes. 相似文献
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Reviews the book, Normality and the life cycle: A critical integration by Daniel Offer and Melvin Sabshin (1984). In 1966 and 1974, Basic Books published the first and second editions of Offer and Sabshin's Normality: Theoretical and Clinical Concepts of Mental Health. These volumes generated the proposal that a new field, called normatology, be established. It would focus on normality, normal behavior, and normal development. This still more recent volume develops the proposal and is an attempt to fill the need to "examine concepts of normality and definitions of normal behavior through time and across cultures". Both of the editors (and most of the contributors) are medically trained, and their professional orientation is apparent throughout the book. Although claims are made that the approach to normatology should be interdisciplinary, and four different concepts of normality are offered, the main concern of most of the chapters seem to be that of differentiating the healthy from the unhealthy. The editors even note that the terms "normality" and "mental health" are used interchangeably. Several chapters have a developmental orientation, but these too are typically concerned with distinguishing normal from abnormal developmental processes. Individual papers are scholarly, but in some cases seem directionless. The most seminal ideas in the book are presented by Mandell and Salk, whose chapter proposes a theory of emergent patterns that could have implications in the future both for general developmental theory and for specific theories of learning that might influence rehabilitation psychology. A previous reviewer has judged that this chapter alone is worth the price of the book, and this judgment may well be correct. Those who purchase this book should do so primarily for its reviews of the literature, which are generally complete and competent. Purchasers will probably be disappointed if they expect to find much that is of direct value to rehabilitation or that contributes in a substantive to the founding of a new science of normality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献