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51.
This paper investigates uncertainties in complex supply chain situations and proposes a fuzzy-based decision support model for determining the chance of meeting on-time delivery in a complex supply chain environment. It integrates fuzzy logic principles and unitary structure-based supply chain model and enables addressing uncertainties associated with key inputs of on-time delivery performance for effective decision making process. The proposed pragmatic model deals with the fuzziness of the key inputs including, variations in demand forecasting, materials shortages and distribution lead time, and combines a fuzzy reasoning approach for monitoring on-time delivery of finished products. In systematically dealing with the uncertainties of complex supply chains, this model supports the minimizing of business losses that result from penalties and customer dissatisfaction, and the consequent reduced market share. Application of the proposed model is illustrated using a textile industry case study.  相似文献   
52.
通过声音来实现故障诊断在工业领域应用比较广泛。本文的主要目标是给出故障空调在运行状态下的声音,使用Zadeh推理的方法对故障空调的声音进行识别,进而推断出空调内部具体哪个部件或零件发生故障。本文首先对声音进行快速傅里叶变换,根据三分之一倍频程对整个频率进行划分,并对生成的频率进行标准化处理;当空调内部的零部件发生损坏时,噪音峰值就会在某一段或几段频率中有升高,从而提取每个频程的峰值作为特征向量。通过“专家经验”得出一个逻辑关系R矩阵,使用matlab软件将特征向量与R矩阵进行点积运算得到故障诊断的结果,最后GUI界面呈现出结果。实验表明,本方法对空调噪音的识别诊断效果比较理想。最后给出本方法适用的一些条件。本方法的实现原理简单,在空调噪音故障诊断应用领域可以有一定的应用空间。  相似文献   
53.
应用自主研发的具有分离-富集模式的制备色谱工厂,建立了分离制备五味子木脂素有效部位及其单体化合物的方法。该方法首先以C18(250 mm×4.6 mm,5 μm)为色谱柱,水和甲醇为流动相,分离度和保留时间为考察指标,采集4个不同梯度的色谱信息,通过XTool色谱专家系统软件模拟,确定五味子木脂素第一、二维色谱条件;然后采用线性放大的方法,以C18(250 mm×30 mm,10 μm)为第一、二维分离柱,C18(80 mm×30 mm,10 μm)为富集柱,水为富集稀释液,对五味子木脂素进行二维色谱分离纯化;最后第一维分离得到9个可重复组分,第二维分离得到20个高纯度化合物,其中有6个单体化合物。结果表明该法重现性良好,可以实现五味子木脂素的系统性分离,对五味子化学成分的研究具有重要意义。  相似文献   
54.
As an extension of intuitionistic fuzzy sets, the theory of picture fuzzy sets not only deals with the degrees of rejection and acceptance but also considers the degree of refusal during a decision-making process; therefore, by incorporating this competency of picture fuzzy sets, the goal of this study is to propose a novel hybrid model called picture fuzzy soft expert sets by combining picture fuzzy sets with soft expert sets for dealing with uncertainties in different real-world group decision-making problems. The proposed hybrid model is a more generalized form of intuitionistic fuzzy soft expert sets. Some novel desirable properties of the proposed model, namely, subset, equality, complement, union and intersection, are investigated together with their corresponding examples. Two well-known operations AND and OR are also studied for the developed model. Further, a decision-making method supporting by an algorithmic format under the proposed approach is presented. Moreover, an illustrative application is provided for its better demonstration, which is subjected to the selection of a suitable company of virtual reality devices. Finally, a comparison of the initiated method is explored with some existing models, including intuitionistic fuzzy soft expert sets.  相似文献   
55.
针对大型企业供配电网随机谐振故障问题进行分析研究。建立了某企业供电网铁磁谐振非线性框图模型,仿真表明系统会产生铁磁谐振。由于谐振表现形式具有一定的模糊性,引入模糊方法,建立了故障征兆的模糊隶属度函数。提出了一种故障诊断的模糊表达式,及基于模糊产生式规则的故障  相似文献   
56.
Based on a simple outranking method of multi-attribute decision making (MADM), called Dichotomy-Cut, developed in recent years and published elsewhere, this paper describes how to reliably elicit the necessary decision knowledge for implementing various decision modes via this method and its computerized support - UNIDAS 2. The most important features of this method are outlined, namely, how to compose the preference ordered matrices and which are the basic decision rules. Special attention should be paid to specific interactive group decision behaviour of experts. Two examples plainly explain the contents discussed.  相似文献   
57.
58.
Leontief substitution systems have been studied by economists and operations researchers for many years. We show how such linear systems are naturally viewed asLeontief substitution flow problems on directed hypergraphs, and that important solution properties follow from structural characteristics of the hypergraphs. We give a strongly polynomial, non-simplex algorithm for Leontief substitution flow problems that satisfy againfree property leading to acyclic extreme solutions. Integrality conditions follow easily from this algorithm. Another structural property,support disjoint reachability, leads to necessary and sufficient conditions for extreme solutions to be binary. In a survey of applications, we show how the Leontief flow paradigm links polyhedral combinatorics, expert systems, mixed integer model formulation, and some problems in graph optimization.Dedicated to the memory of Robert G. JeroslowSee Acknowledgement section.Research supported in part by the ONR (Office of Naval Research) under URI Grant number N00014-86-K-0689, and Center for Operations Research and Econometrics, Universite Catholique de Louvain.  相似文献   
59.
A novel approach to molecular structure elucidation based on ranking chemical structures in agreement with the13C NMR chemical shift/charge density linear relationship is suggested. The structure having the lowest standard approximation error (SAE) is considered to be the correct one. Each ranked structure is additionally tested for the13C chemical shift equivalence corresponding to its constitutional symmetry (in terms of the charge densities).This paper is Part VI of the series Automatic assignment of13C NMR signals. For Part V see ref. [1].  相似文献   
60.
We first review Zadeh's theory for representing and reasoning with quantified statements of the formQ A's are B. We then suggest an equivalent representation in terms ofQ X's are (A B). We briefly look at some implications of this new representation.  相似文献   
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