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1.
基于DS/AHP的供应商选择方法   总被引:4,自引:0,他引:4  
梁昌勇  陈增明  丁勇 《运筹与管理》2005,14(6):33-38,56
供应商选择方法有很多种,在众多的方法中层次分析法以能够将定性指标定量化而被广泛应用于供应商选择决策中。考虑到供应商选择问题中包含有很多的不确定性而证据理论在处理不确定问题又有着独特的优点,因此本文采用了一种由层次分析法和证据理论结合而产生的DS/AHP决策方法,并将其应用于供应商选择决策问题中,该方法综合了层次分析法和证据理论的优点,可以更科学的进行供应商选择决策,最后通过一个例子说明这种方法在供应商选择中的应用。  相似文献   
2.
本文用多元统计的方法 ,将物证检验中彼此相关的特征转化为不相关的新特征 ,再利用L和L 检验方法 ,大大拓广了L和L 检验方法的使用范围 ,提高了破案率。  相似文献   
3.
Weber electrodynamics predicts the Kaufmann-Bucherer experiments and the fine structure energy level splitting of the H-atom (neglecting spin) without mass change with velocity (i.e., mass ). The Weber potential for the gravitational case yields Newtonian mechanics, confirming Mach's principle. It provides a cosmological condition yielding an estimated radius of the universe of 8 × 109 light years. Despite these successes, the independent evidence for Kaufmann mechanics, where mass changes with velocity (i.e., mass ) is convincing. Perhaps a slight alteration may make the Weber theory compatible with Kaufmann mechanics.  相似文献   
4.
The significant role of the proton exchange and homoconjugation (formation of AHA and A1HA 1 complexes) equilibria in protonic hetero systems (HA+A 1 ) has been shown from analysis of published data and from my own simple experiments. It is concluded that there is a need to reconsider some basic hydrogen bond problems. One of these problems-the existence of heteroconjugates in polar solvents — has been verified and illustrated with suitable experimental evidence (IR and UV-VIS spectra). The most accepted experimental evidence for the double minimum potential in the hydrogen bridge has been questioned as being in disagreement with the equilibrium law. A simple relation between the heteroconjugation constant, the parent homoconjugation constants and the proton exchange constant is also postulated. This relation fulfills important theoretical requirements, however, it is not applicable in extreme cases.To the memory of Bogdan Przybyszewski.  相似文献   
5.
ABSTRACT

A method for combining statistical-based QSAR predictions of two or more binary classification models is presented. It was assumed that all models were independent. This facilitated the combination of positive and negative predictions using a quantitative weight of evidence (qWoE) procedure based on Bayesian statistics and the additivity of the logarithms of the likelihood ratios. Previous studies combined more than one prediction but used arbitrary strengths for positive and negative predictions. In our approach, the combined models were validated by determining the sensitivity and specificity values, which are performance metrics that are a point of departure for obtaining values that measure the weight of evidence of positive and negative predictions. The developed method was experimentally applied in the prediction of Ames mutagenicity. The method achieved a similar accuracy to that of the experimental Ames test for this endpoint when the overall prediction was determined using a combination of the individual predictions of more than one model. Calculating the qWoE value would reduce the requirement for expert knowledge and decrease the subjectivity of the prediction. This method could be applied to other endpoints such as developmental toxicity and skin sensitisation with binary classification models.  相似文献   
6.
结晶聚合物中间层理论与实验佐证   总被引:3,自引:0,他引:3  
概述了Flory和Yoon由晶格模型出发,从理论上证明了结晶聚合物中间层的存在以及近年来许多学者采用多种实验技术确认中间层存在的事实。  相似文献   
7.
It is appropriate to use Dempster's rule for combining belief functions only if the belief functions combined are based on independent items of evidence. What can be done in the case of dependent evidence? Often the answer is to reframe the problem. Three examples are given: one from everyday experience, one from probabilistic relaxation, and one from expert systems.  相似文献   
8.
提出了用联合变换相关器(JTC)来实现证据理论概率分配函数正交和的光学计算,在理论上对于如何用联合变像相关器实现证据理论分配函数正交和作了详细的讨论,并作了相应的仿真测试,结果显示该方法是可行的。与John Caulfield提出的用声光器件矢量外积实现的正交和计算相比,在该结构中由于采用二进制编码的数值计算,因此其计算精度得到了提高,同时对联合变换相关器输入端二进制编码的数值空间位置的适当调整可以直接得到所需要的证据理论正交和矢量,在处理步骤上得到了简化。  相似文献   
9.
基于红外/毫米波双模融合的目标识别方法   总被引:2,自引:1,他引:1  
在数据融合的基础上,以红外/毫米波双模传感器的智能融合结构为模型,将模糊神经网络与D-S证据理论相结合,提出了一种新的目标识别方法.该算法根据红外/毫米波传感器的性能及工作范围,构造模糊变量作为神经网络的输入,根据神经网络的不同输出判别目标的真伪,并利用D-S证据理论进行目标身份识别.仿真结果证明了该算法的可行性.  相似文献   
10.
Grafting polymer glycols onto nano-silica surface through one-step procedure was investigated. The major characteristic of this procedure is that all the materials and reagents (silica, PEG, TDI, DBTDL, solvent) required for grafting were added simultaneously into the reaction vessel. TDI and DBTDL were used as coupling agent and catalyst, respectively.The products were characterized by FTIR, TGA, elemental analyses and TEM, giving evidence for successful grafting of PEG. Possible mechanism of this grafting was studied and two grafting processes were proposed. The process through which the grafting proceeds depends on the reaction temperature. Effect of molecular weight of PEG on grafting was also investigated.  相似文献   
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