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41.
42.
N. Zaerpour M. Rabbani A. H. Gharehgozli R. Tavakkoli-Moghaddam 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(11):1035-1054
Manufacturing systems produce their products by making use of three main strategies: make-to-order, make-to-stock and hybrid
(combination of MTO and MTS strategies) systems. Hence, several products must be considered and partitioned in terms of many
different conflicting criteria, leading to a large set of subjective or ambiguous data. Thus, an effective evaluation approach
is essential to improve decision quality. In this paper a comprehensive decision, making structure is proposed to choose the
proper strategy for producing the products. It consists of a novel hybrid methodology, which combines analytical hierarchy
process (AHP) and technique for order performance by similarity to ideal solution (TOPSIS) for partitioning of products. In
this study, the rating of each alternative regarding different criteria (throughout the TOPSIS technique) is described by
means of linguistic variables. Furthermore, fuzzy AHP methodology is applied to determine the weights of evaluation criteria.
At the end, the effectiveness of the proposed model is demonstrated through a case study. 相似文献
43.
Lydie du Bousquet Masahide Nakamura Ben Yan Hiroshi Igaki 《Innovations in Systems and Software Engineering》2009,5(3):181-196
A home network system consists of multiple networked appliances, intended to provide more convenient and comfortable living
for home users. Before being deployed, one has to guarantee the correctness, the safety, and the security of the system. Here,
we present the approach chosen to validate the Java implementation of a home network system. We rely on the Java Modelling
Language to formally specify and validate an abstraction of the system.
This is a substantially revised version of our paper that appeared in the proceedings of the Workshop On Leveraging Applications
of Formal Methods, Verification and Validation (ISoLA), Poitiers-Futuroscope, France, December 2007. 相似文献
44.
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46.
Daniel Cosmin Porumbel Jin-Kao Hao Pascale Kuntz 《Computers & Operations Research》2010,37(4):769-778
We present a search space analysis and its application in improving local search algorithms for the graph coloring problem. Using a classical distance measure between colorings, we introduce the following clustering hypothesis: the high quality solutions are not randomly scattered in the search space, but rather grouped in clusters within spheres of specific diameter. We first provide intuitive evidence for this hypothesis by presenting a projection of a large set of local minima in the 3D space. An experimental confirmation is also presented: we introduce two algorithms that exploit the hypothesis by guiding an underlying Tabu Search (TS) process. The first algorithm (TS-Div) uses a learning process to guide the basic TS process toward as-yet-unvisited spheres. The second algorithm (TS-Int) makes deep investigations within a bounded region by organizing it as a tree-like structure of connected spheres. We experimentally demonstrate that if such a region contains a global optimum, TS-Int does not fail in eventually finding it. This pair of algorithms significantly outperforms the underlying basic TS algorithm; it can even improve some of the best-known solutions ever reported in the literature (e.g. for dsjc1000.9). 相似文献
47.
M. CastroAuthor Vitae B. KumarAuthor VitaeJ.F. FellerAuthor Vitae Z. HaddiAuthor VitaeA. AmariAuthor Vitae B. BouchikhiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):213-219
We report the original design of a new type of electronic nose (e-nose) consisting of only five sensors made of hierarchically structured conductive polymer nanocomposites (CPC). Each sensor benefits from both the exceptional electrical properties of carbon nanotubes (CNT) used to build the conductive architecture and the spray layer by layer (sLbL) assembly technique, which provides the transducers with a highly specific 3D surface structure. Excellent sensitivity and selectivity were obtained by optimizing the amount of CNT with five different polymer matrices: poly(caprolactone) (PCL), poly(lactic acid) (PLA), poly(carbonate) (PC), poly(methyl methacrylate) (PMMA) and a biobased polyester (BPR). The ability of the resulting e-nose to detect nine organic solvent vapours (isopropanol, tetrahydrofuran, dichloromethane, n-heptane, cyclohexane, methanol, ethanol, water and toluene), as well as biomarkers for lung cancer detection in breath analysis, has been demonstrated. Principal component analysis (PCA) proved to be an excellent pattern recognition tool to separate vapour clusters. 相似文献
48.
本文介绍了分别基于西门子S7—300PLC和S7—400PLC的两种冗余控制系统在荆门石化和鞍钢变压吸附制氢装置中的应用。概述了工艺过程和工艺对控制系统的要求,着重对上述两套系统的硬件配置和软件编程组态实施方案进行了描述。运行结果表明,上述系统稳定可靠,控制效果良好,能满足工艺要求。 相似文献
49.
本文在常规火电厂主蒸汽温度自动控制方案的基础上,对200MW乏气送粉机组的特性进行了分析,结合锅炉主要参数与主蒸汽温度自动控制的相互关系,以及相关的工艺要求,提出了一种新的优化方案。 相似文献
50.
目前音频数据库的研究相对于图象处于滞后,文中侧重音乐角度,结合MPEG标准和基于内容检索的应用,综述了音频检索的研究现状,分析了音频方面研究的特殊性和相关应用中的问题;并提出基于独立分量分析(ICA)的按调查询(QBH)的系统,较好地解决了特征提取中的鸡尾酒会效应问题。系统的查询结果置于三维声效环境中加速了查询。 相似文献