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71.
从劳务市场的现状入手,分析劳务合同存在的问题,寻找解决办法,有利于对建筑市场进行行政指导、行政监督和建筑业企业的健康发展。 相似文献
72.
Reviews the book, Depression in the medically ill: An integrated approach by G. Rodin, J. Craven, and C. Littlefield (see record 1991-97973-000). This book provides an in-depth coverage of current issues in the management of depression in the medically ill. The book is balanced in theoretical perspective and quite comprehensive in coverage of the empirical literature. The authors are well known to the area of depression and physical illness. The book is organized into three main sections dealing with 1) Clinical Presentation, 2) Etiology and Pathogenesis, and 3) Treatment. Numerous case examples are provided throughout to highlight different aspects of symptom presentation, diagnostic problems, and therapeutic management. Notably lacking from the review of prevalence studies is the work examining depression and chronic pain populations. In sum, Rodin et al. have drawn on a vast literature to provide a clear and coherent picture of the current state of knowledge and theory dealing with depression and medical illness. Their book joins a number of recent papers attempting to draw more attention to clinical issues in the management of depression in the medically ill. I would recommend the book to all clinicians who work with medically ill populations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Louis Esperet 《Information Processing Letters》2007,101(5):215-219
A graph G is 2-outerplanar if it has a planar embedding such that the subgraph obtained by removing the vertices of the outer face is outerplanar. The oriented chromatic number of an oriented graph H is defined as the minimum order of an oriented graph H′ such that H has a homomorphism to H′. In this paper, we prove that 2-outerplanar graphs are 4-degenerate. We also show that oriented 2-outerplanar graphs have a homomorphism to the Paley tournament QR67, which implies that their (strong) oriented chromatic number is at most 67. 相似文献
74.
Three coupling strategies in matching the Ritz-Galerkin method and the finite element method are introduced for general elliptic equations, and useful numerical techniques are provided. Numerical experiments have been carried out for solving the typical, singular Motz problem, which shows that optimal convergence rates of numerical solutions can be achieved by using the combined methods and techniques provided in this paper. 相似文献
75.
We consider an integer-subset representation problem motivated by a medical application in radiation therapy. We prove NP-completeness, derive nontrivial bounds, and report on the performance of a greedy heuristic. 相似文献
76.
In this note, we show that any distributive lattice is isomorphic to the set of reachable configurations of an Edge Firing Game. Together with the result of James Propp, saying that the set of reachable configurations of any Edge Firing Game is always a distributive lattice, this shows that the two concepts are equivalent. 相似文献
77.
78.
随着当前世界经济的快速发展,我们已经进入了信息化和数字化的时代,在这种大的背景下,做好信息的安全管理和评估尤为重要,并越来越受到人们的重视。文章就从这一问题出发,其中根据当前信息安全监管过程中出现的相关问题展开分析,并重点探讨了信息技术在安全评估当中的应用问题。 相似文献
79.
《Optimization methods & software》2012,27(4):573-585
Interior point (IP) algorithms for Min Cost Flow (MCF) problems have been shown to be competitive with combinatorial approaches, at least on some problem classes and for very large instances. This is in part due to availability of specialized crossover routines for MCF; these allow early termination of the IP approach, sparing it with the final iterations where the Karush Kuhn-Tucker (KKT) systems become more difficult to solve. As the crossover procedures are nothing but combinatorial approaches to MCF that are only allowed to perform few iterations, the IP algorithm can be seen as a complex ‘multiple crash start’ routine for the combinatorial ones. We report our experiments of allowing one primal-dual combinatorial algorithm to MCF to perform as many iterations as required to solve the problem after being warm-started by an IP approach. Our results show that the efficiency of the combined approach critically depends on the accurate selection of a set of parameters among very many possible ones, for which designing accurate guidelines appears not to be an easy task; however, they also show that the combined approach can be competitive with the original combinatorial algorithm, at least on some ‘difficult’ instances. 相似文献
80.
A comparative study between dynamic adapted PSO and VNS for the vehicle routing problem with dynamic requests 总被引:1,自引:0,他引:1
Combinatorial optimization problems are usually modeled in a static fashion. In this kind of problems, all data are known in advance, i.e. before the optimization process has started. However, in practice, many problems are dynamic, and change while the optimization is in progress. For example, in the dynamic vehicle routing problem (DVRP), new orders arrive when the working day plan is in progress. In this case, routes must be reconfigured dynamically while executing the current simulation. The DVRP is an extension of a conventional routing problem, its main interest being the connection to many real word applications (repair services, courier mail services, dial-a-ride services, etc.). In this article, a DVRP is examined, and solving methods based on particle swarm optimization and variable neighborhood search paradigms are proposed. The performance of both approaches is evaluated using a new set of benchmarks that we introduce here as well as existing benchmarks in the literature. Finally, we measure the behavior of both methods in terms of dynamic adaptation. 相似文献