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51.
Jing-Wei Liu Ching-Hsue Cheng Yao-Hsien Chen Tai-Liang Chen 《Expert systems with applications》2010,37(1):610-617
Business operation performance is related to corporation profitability and directly affects the choices of investment in the stock market. This paper proposes a hybrid method, which combines the ordered weighted averaging (OWA) operator and rough set theory after an attribute selection procedure to deal with multi-attribute forecasting problems with respect to revenue growth rate of the electronic industry. In the attribute selection step, four most-important attributes within 12 attributes collected from related literature are determined via five attribute selection methods as the input of the following procedure of the proposed method. The OWA operator can adjust the weight of an attribute based on the situation of a decision-maker and aggregate different attribute values into a single aggregated value of each instance, and then the single aggregated values are utilized to generate classification rules by rough set for forecasting operation performance.To verify the proposed method, this research collects the financial data of 629 electronic firms for public companies listed in the TSE (Taiwan Stock Exchange) and OTC (Over-the-Counter) market in 2004 and 2005 to forecast the revenue growth rate. The results show that the proposed method outperforms the listing methods. 相似文献
52.
针对复杂无序的实际分形生长系统,研究了环境干扰下分形生长的定方位控制模型.不同于以往对分形生长的定方位的研究仅限于对它的实验方面的讨论,本文利用范数理论得到了干扰项为广义函数时控制生长粒子凝聚到不同方位的定量方法.利用所提出的控制方法解决了干扰项为更一般函数形式的定方向生长问题,并以非线性项为二次多项式、正弦函数为例,运用所得的定量关系对该系统不同作用区域的生长粒子进行了控制,仿真结果表明了该控制方法的有效性. 相似文献
53.
Veikko Kernen 《Theoretical computer science》2009,410(38-40):3893-3900
54.
Software reliability is one of the most important quality attributes of commercial software. During software testing, software reliability growth models (SRGMs) are commonly used to describe the phenomenon of failure occurrence and/or fault removal which consequently enhancements software reliability. Large software systems are developed by integrating a number of relatively small and independent modules, which are tested independently during module testing phase. The amount of testing resource available is limited which is desired to be consumed judiciously so as to optimize the testing process. In this paper we formulate a resource allocation problem of minimizing the cost of software testing under available amount of testing resource, given a reliability constraint. We use a flexible SRGM considering testing effort which, depending upon the values of parameters, can describe either exponential or S-shaped failure pattern of software modules. A systematic and sequential Algorithm is proposed to solve the optimization problem formulated. Numerical examples are given to illustrate the formulation and solution procedures. Sensitivity analysis is performed to examine the behavior of some parameters of SRGM with most significant influence. 相似文献
55.
56.
丁红 《数字社区&智能家居》2008,3(12):1697-1699
提出一种用模板匹配来检测CT增强扫描中的小肝癌的算法,该算法先利用改进的区域生长方法提取出完整的肝部以减少模板匹配的计算量,然后简化Y Lee等人的模板匹配方法,从而达到加快计算速度的目的。 相似文献
57.
Incremental Evolution in ANNs: Neural Nets which Grow 总被引:1,自引:1,他引:0
This paper explains the optimisation of neuralnetwork topology using Incremental Evolution;that is, by allowing the network to expand byadding to its structure. This method allows anetwork to grow from a simple to a complexstructure until it is capable of fulfilling itsintended function. The approach is somewhatanalogous to the growth of an embryo or theevolution of a fossil line through time, it istherefore sometimes referred to as anembryology or embryological algorithm. Thepaper begins with a general introduction,comparing this method to other competingtechniques such as The Genetic Algorithm, otherEvolutionary Algorithms and SimulatedAnnealing. A literature survey of previous workis included, followed by an extensive newframework for application of the technique.Finally, examples of applications and a generaldiscussion are presented. 相似文献
58.
Formalized study of self-assembly has led to the definition of the tile assembly model [Erik Winfree, Algorithmic self-assembly of DNA, Ph.D. Thesis, Caltech, Pasadena, CA, June 1998; Paul Rothemund, Erik Winfree, The program-size complexity of self-assembled squares, in: ACM Symposium on Theory of Computing, STOC02, Montreal, Quebec, Canada, 2001, pp. 459–468]. Research has identified two issues at the heart of self-assembling systems: the number of steps it takes for an assembly to complete, assuming maximum parallelism, and the minimal number of tiles necessary to assemble a shape. In this paper, I define the notion of a tile assembly system that computes a function, and tackle these issues for systems that compute the sum and product of two numbers. I demonstrate constructions of such systems with optimal Θ(1) distinct tile types and prove the assembly time is linear in the size of the input. 相似文献
59.
根际环境因子对马铃薯块茎生长发育具有重要影响。马铃薯根际环境因子包括光照、温度、水分、空气、营养以及重力等,从生态学的角度综述了根际环境因子对马铃薯块茎生长发育的影响,并对存在的问题及其研究进展进行了讨论。 相似文献
60.
《Information Technology for Development》2012,18(4):iii-xxiii
ABSTRACTUsing data on major Indian states during 2001–2014, the paper analyzes the impact of AIM (Aadhaar, Inclusion and Mobile) trinity on economic growth. Using advanced panel data techniques, the evidence suggests that mobile penetration exerts a positive and statistically significant impact on economic growth. In addition, there exist strong complementarities between mobile telephony and financial inclusion. The magnitude of the complementarity is significantly higher in case of financial use as compared with financial access. In addition, the evidence points to the fact that biometric identification process (Aadhaar) is making its impact felt on financial inclusion, primarily by improving financial access. 相似文献