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1.
A method is considered to solve a conditional optimization problem with a linear-fractional objective function over permutations.
The performance of sub algorithms to solve this problem is evaluated. The practical efficiency of the algorithm is analyzed
by conducting numerical experiments.
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Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 133–146, July–August 2007. 相似文献
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TIC is a timed algebraic calculus which combines ideas from asynchronous and synchronous calculi. Time is introduced by assigning explicit time restrictions to the events of an asynchronous calculus. The semantics is defined in an operational way. Interleaving of behaviours is defined in such a way that a proper merge of events in time is achieved. Weak timed bisimulation is also defined. Examples are presented to show the applicability of the calculus to the study of timed behaviours.This work was partially supported by CICYT under the TIC program (MEDAS project) 相似文献
5.
Oxide films formed by water oxidation at 360°C on ZrNb(1%)O(0.13%) for several durations (50-300 days) were studied by impedance spectroscopy (IS) in gaseous atmosphere. The electrical behavior of oxide layers was investigated as a function of the temperature (25-300°C) at constant oxygen partial pressure (0.3 Pa). Cole-Cole diagrams suggest a frequency-temperature equivalence. A simple electrical model has been derived from the as-deduced 14 decade master curve. Equivalent circuit includes a series association of two layers exhibiting different dielectric properties: a dense layer near the oxide-metal interface and a porous layer at the waterside. Electronic conductivity is predominant within the whole temperature range, but ionic contribution was proposed to increase for temperature higher than 170°C. During the parabolic oxidation step, the oxide thickness of the barrier layer increases but oxide growth would not be only a geometrical one. The kinetic modification to a constant oxidation rate was observed to be correlated to the increase of the dense layer thickness. Such a behavior suggests that the mechanism controlling oxidation rate is not a pure mechanism of oxygen diffusion through this layer. Finally, a qualitative model of activated electrons transport based on an hopping mechanism was proposed in order to take into account that the Arrhenius diagrams of both total conductivity and dispersion factor are characterized by a break point with two activation energy values. 相似文献
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带类型的λ-演算是一个逻辑系统,它可以作为程序语言的基础.Plotkin所引进的PCF就是这样一类程序语言.Plotkin构造了PCF的一个模型,然后讨论与这个模型相关的指称语义和操作语义之间的配合问题──简单配合和完全配合.本文利用Scott引进的信息系统概念构造PCF的另一种模型,并证明与这个模型对应的指称语义与操作语义是完全配合的. 相似文献
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Physical optics (PO) is an approximation method for high‐frequency scattering and diffraction problems. But PO fields are inaccurate in the shadow region where the source is screened by the scatter. Two key factors of the error for PO are (i) edge diffraction coefficients and (ii) existence of fictitious penetrating rays. The correction with respect to the former has been extensively investigated by many authors using various ray techniques such as GTD, UTD, and UAT. On the other hand, the latter was identified recently by the authors. This paper proposes novel PO‐based calculation procedures termed PO‐AF and PTD‐AF, where PO and Aperture Field Integration Method (AFIM) are merged with the help of special elementary diffraction coefficients. These can uniformly cover the whole angular region and only the error factor (ii) is removed in PO‐AF while both (i) and (ii) are removed in PTD‐AF. The theoretical backgrounds of PO currents are discussed in terms of field equivalence theorem and visualization of EM waves. Next, new methods are proposed and their validity is numerically demonstrated for 2D scattering problems of a strip, a corner reflector, and a cylinder of circular arc. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 1–10, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20037 相似文献
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16Mn连涛坯进行控轧时,按铸坯碳当量的上限和下限,分别采用两种不同的控轧制度。在邯钢中板分厂试轧的结果,轧材合格率均达到96%以上,投产后轧材合格率达到98%以上。 相似文献
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Michael G. Main 《International journal of parallel programming》1987,16(5):383-400
A basic question in the theory of communicating processes is “When should two processes be considered equivalent?”. Attempts to answer this question have led to the concepts of observation equivalence, bisimulations, testing equivalence, failure equivalence, etc. The main point of this paper is to increase the understanding and motivation for two of these equivalences, namely failure and testing equivalences. The approach starts with the idea that the equivalence of processes should be reducible to the visible sequences of actions which a process performs in various contexts. This idea is implemented by a string-based semantic order for communicating processes where divergence is catastrophic. Under some assumptions about contexts, the resulting semantics is shown to be equivalent to theimproved failure semantics of Brookes and Roscoe(1) and also to themust testing-semantics of Hennessy and DeNicola.(2–4) This characterization gives independent support for the appropriateness of failures and testing. 相似文献
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