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161.
This paper presents a comprehensive review of the work done, during the 1968–2005, in the application of statistical and intelligent techniques to solve the bankruptcy prediction problem faced by banks and firms. The review is categorized by taking the type of technique applied to solve this problem as an important dimension. Accordingly, the papers are grouped in the following families of techniques: (i) statistical techniques, (ii) neural networks, (iii) case-based reasoning, (iv) decision trees, (iv) operational research, (v) evolutionary approaches, (vi) rough set based techniques, (vii) other techniques subsuming fuzzy logic, support vector machine and isotonic separation and (viii) soft computing subsuming seamless hybridization of all the above-mentioned techniques. Of particular significance is that in each paper, the review highlights the source of data sets, financial ratios used, country of origin, time line of study and the comparative performance of techniques in terms of prediction accuracy wherever available. The review also lists some important directions for future research. 相似文献
162.
This paper proposes an approach to critical path analysis for a project network with activity times being fuzzy numbers, in that the membership function of the fuzzy total duration time is constructed. The basic idea is based on the extension principle and linear programming formulation. A pair of linear programs parameterized by possibility level α is formulated to calculate the lower and upper bounds of the fuzzy total duration time at α. By enumerating different values of α, the membership function of the fuzzy total duration time is constructed, and the fuzzy critical paths are identified at the same time. Moreover, by applying the Yager ranking method, definitions of the most critical path and the relative degree of criticality of paths are developed; and these definitions are theoretically sound and easy to use in practice. Two examples with activity times being fuzzy numbers of L-R and L-L types discussed in previous studies are solved successfully to demonstrate the validity of the proposed approach. Since the total duration time is completely expressed by a membership function rather than by a crisp value, the fuzziness of activity times is conserved completely, and more information is provided for critical path analysis. 相似文献
163.
Decision makers (DMs)’ preferences on decision alternatives are often characterized by multiplicative or fuzzy preference relations. This paper proposes a chi-square method (CSM) for obtaining a priority vector from multiplicative and fuzzy preference relations. The proposed CSM can be used to obtain a priority vector from either a multiplicative preference relation (i.e. a pairwise comparison matrix) or a fuzzy preference relation or a group of multiplicative preference relations or a group of fuzzy preference relations or their mixtures. Theorems and algorithm about the CSM are developed. Three numerical examples are examined to illustrate the applications of the CSM and its advantages. 相似文献
164.
A method is described for obtaining conjunctive normal forms for logics using Gentzen-style rules possessing a special kind of strong invertibility. This method is then applied to a number of prominent fuzzy logics using hypersequent rules adapted from calculi defined in the literature. In particular, a normal form with simple McNaughton functions as literals is generated for ?ukasiewicz logic, and normal forms with simple implicational formulas as literals are obtained for Gödel logic, Product logic, and Cancellative hoop logic. 相似文献
165.
Arindam Roy Manas Kumar Maiti Samarjit Kar Manoranjan Maiti 《Mathematical and Computer Modelling》2007,46(11-12):1419-1433
An inventory model for a deteriorating item with stock dependent demand is developed under two storage facilities over a random planning horizon, which is assumed to follow exponential distribution with known parameter. For crisp deterioration rate, the expected profit is derived and maximized via genetic algorithm (GA). On the other hand, when deterioration rate is imprecise then optimistic/pessimistic equivalent of fuzzy objective function is obtained using possibility/necessity measure of fuzzy event. Fuzzy simulation process is proposed to maximize the optimistic/pessimistic return and finally fuzzy simulation-based GA is developed to solve the model. The models are illustrated with some numerical data. Sensitivity analyses on expected profit function with respect to distribution parameter λ and confidence levels α1 and α2 are also presented. 相似文献
166.
针对一类非仿射的不确定非线性系统,利用H∞控制技术和模糊系统,提出一种基于观测器的混合的直接自适应模糊控制方法,该方法不需要系统的状态变量完全可测,同时取消了最优逼近误差平方可积的假设条件,而且跟踪误差渐近收敛到零。仿真结果表明所提设计方法的有效性。 相似文献
167.
利用模糊信号码的代数性质给出了模糊信号码的一个充要条件:设A是字母表X上的一个模糊前缀码,那么A是模糊信号码当且仅当X*=T∪A0.∪P0.,这里P=AX-,T={u∈X*|X*uX*∩A0.=φ},满足条件T∩P0.=φ=T∩A0.,T■A0.X .同时讨论了一个模糊码满足X*A0.■A0.X*的一些等价条件,对最大模糊前缀码的性质也作了一些研究。 相似文献
168.
知识约简是机器学习,模式识别,信号处理等领域的主要问题之一。本文介绍了基于单调包含度的模糊决策信息系统的知识约简。证明了模糊决策信息系统的约简即是其对应信息系统的约简,从而为该种模糊决策信息系统的知识约简提供了简单直接的方法。 相似文献
169.
Bouchra Lamrini Marie-Vronique Le Lann Ahmed Benhammou El Khadir Lakhal 《Comptes Rendus Physique》2005,6(10):1161-1168
The present Note proposes a learning classification methodology to identify functional states on a coagulation process involved in drinking water treatment. In this work, we chose to carry out the supervised control of this process while using the LAMDA (Learning Algorithm for Multivariate Data Analysis) classification technique. The LAMDA classification technique proposes the interactive participation of the expert operator during the learning phase and in the optimisation of the classification. In this work, all information stemming from the environment process as well as expert knowledge has been aggregated and exploited. The application chosen for state identification is the Rocade drinking water treatment plant located at Marrakech, Morocco. To cite this article: B. Lamrini et al., C. R. Physique 6 (2005). 相似文献
170.