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41.
42.
Many real-world problems are multi-objective optimization problems and evolutionary algorithms are quite successful on such problems. Since the task is to compute or approximate the Pareto front, multi-objective optimization problems are considered as more difficult than single-objective problems. One should not forget that the fitness vector with respect to more than one objective contains more information that in principle can direct the search of evolutionary algorithms. Therefore, it is possible that a single-objective problem can be solved more efficiently via a generalized multi-objective model of the problem. That this is indeed the case is proved by investigating the computation of minimum spanning trees.This work was supported by the Deutsche Forschungsgemeinschaft (DFG) as part of the Collaborative Research Center Computational Intelligence (SFB 531) and by the German-Israeli Foundation (GIF) in the project Robustness Aspects of Algorithms. 相似文献
43.
Acceptance, the willingness to experience thoughts, feelings, and physiological sensations without having to control them or let them determine one's actions, is a major individual determinant of mental health and behavioral effectiveness in a more recent theory of psychopathology. This 2-wave panel study examined the ability of acceptance also to explain mental health, job satisfaction, and performance in the work domain. The authors hypothesized that acceptance would predict these 3 outcomes 1 year later in a sample of customer service center workers in the United Kingdom (N = 412). Results indicated that acceptance predicted mental health and an objective measure of performance over and above job control, negative affectivity, and locus of control. These beneficial effects of having more job control were enhanced when people had higher levels of acceptance. The authors discuss the theoretical and practical relevance of this individual characteristic to occupational health and performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Collage grammars are context-free devices which generate picture languages consisting of collages—sets of parts, where a part is a set of points in a given space. In order to show that certain collage languages cannot be generated, the well-known pumping technique turns out to be rather useless. To circumvent this difficulty, other necessary criteria for context-freeness are established in this paper. Roughly speaking, these criteria reveal that (1) the collages in a context-free collage language can be deflated stepwise in such a manner that the difference between subsequent collages in the resulting chain is small and (2) the volume of parts can grow or shrink only exponentially. 相似文献
45.
McKenna Frank P.; Horswill Mark S.; Alexander Jane L. 《Canadian Metallurgical Quarterly》2006,12(1):1
Skill and risk taking are argued to be independent and to require different remedial programs. However, it is possible to contend that skill-based training could be associated with an increase, a decrease, or no change in risk-taking behavior. In 3 experiments, the authors examined the influence of a skill-based training program (hazard perception) on the risk-taking behavior of car drivers (using video-based driving simulations). Experiment 1 demonstrated a decrease in risk taking for novice drivers. In Experiment 2, the authors examined the possibilities that the skills training might operate through either a nonspecific reduction in risk taking or a specific improvement in hazard perception. Evidence supported the latter. These findings were replicated in a more ecological context in Experiment 3, which compared advanced and nonadvanced police drivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
目前,分布式电源架构被广泛用于通信和计算设备中,该电源架构经常采用板载电源(BMP)模块,在尽可能靠近负载点的地方进行电源变换. 相似文献
47.
Sherman Elisabeth M. S.; Strauss Esther; Spellacy Frank; Hunter Michael 《Canadian Metallurgical Quarterly》1995,7(4):440
A 3-factor solution of the Wechsler Adult Intelligence Scale—Revised (WAIS—R; Wechsler, 1981) in 260 adults with suspected head injury suggested relatively good construct validity for the factors, based on correlations with neuropsychological tests purported to measure similar abilities. The Verbal Comprehension factor was related to verbal ability, verbal memory, and executive functioning. The Perceptual Organization factor, although measuring primarily visual–spatial perception and visual constructional ability, was related to visual–spatial memory, visual attention, and executive functioning. The Freedom From Distractibility factor was correlated with two attention measures and was not associated with memory measures. Its association with executive functioning was inconsistent. The findings are discussed in terms of the multidimensional nature of neuropsychological tests and WAIS—R factors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
48.
This article reviews the steps necessary to configure and implement a complex router internetwork. This article will specifically concentrate on Cisco routers, and since they support Transmission Control Protocol/Internet Protocol (TCP/IP) natively, it will concentrate on a backbone network employing that protocol. 相似文献
49.
Matthew John M. Krane Frank P. Incropera 《Metallurgical and Materials Transactions A》1995,26(9):2329-2339
Numerical calculations based on a continuum model are used to examine the effects of solidification shrinkage on the redistribution
of solute in a Pb-19.2 pct Sn mixture which is convectively cooled at a sidewall. For each of three different cooling rates,
separate calculations are performed for shrinkage and buoyancy-induced flows, as well as for the combined influence of shrinkage
and buoyancy effects. The calculations reveal that flow and macrosegregation patterns are more strongly influenced by buoyancy
effects over a wide range of solidification rates. Although extremely large solidification rates yield small regions near
the chilled wall in which shrinkage-induced flows control the redis-tribution of solute, the overall effect on macrosegregation
is small relative to that associated with buoyancy. Scaling analysis of the governing equations produces reference shrinkage
and buoyancy velocities which can be used to extend the current numerical results to other binary systems. 相似文献
50.
Forschung im Ingenieurwesen - Der Aufsatz beschreibt eine Möglichkeit, beliebig vermaschte Wärmenetze numerisch zu simulieren. Basierend auf einer graphentheoretischen Beschreibung der... 相似文献