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971.
In the era of e-businesses, the traditional business services are greatly challenged by the ever-increasing demands from customers with various backgrounds and personalities. Large numbers of new e-businesses are driven by the needs of customers. The existing dynamics inherent in the customer needs require the corresponding dynamic management of services. Attempting to respond to customers in a rapid and intelligent way, this paper proposes a situation calculus based approach for dynamically managing e-Business services in the ubiquitous environment. By employing the formalism of the situation calculus to enable intelligence and automation, the approach can implement. the functions of service automatic composition and model verification. These functions will improve the degree of customer-orientation and enable fast responsiveness in the emerging e-service systems.  相似文献   
972.
Formal systems engineering approaches to modeling misperceptions and attitudes are employed within the framework of the graph model for conflict resolution to systematically study the War of 1812 between the United States of America and Great Britain in order to provide enhanced insights into the causes of the war. More specifically, relational definitions for preferences, movements and stability concepts are defined for describing the attitudes and associated behavior of decision makers involved in a conflict. To capture misperceptions of decision makers in the War of 1812, attitudes are studied within the structure of a hypergame. Combining attitudes and misperceptions within the paradigm of the graph model furnishes the flexible analytical tool which demonstrates that misunderstanding of attitudes by Great Britain and the United States may have contributed to the outbreak of this nasty war.  相似文献   
973.
Polynomial composition is the operation of replacing variables in a polynomial with other polynomials. λ-Grgbner basis is an especial Grobner basis. The main problem in the paper is: when does composition commute with λ-Grobner basis computation? We shall answer better the above question. This has a natural application in the computation of λ-Grobner bases.  相似文献   
974.
利用能够反映动态系统特性的Elman回归神经网络,结合传统的技术分析方法,通过对股票市场的技术指标的建模,寻求股票价格的变化规律,实现对股票价格的预测.实验结果表明,Elman网络具有较好的的逼近性能,能够实现对股票市场的预测.因此,引入技术指标的Elman神经网络用于股市预测是可行、有效的,具有很好的应用前景.  相似文献   
975.
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset.  相似文献   
976.
This study started with problems that my colleagues (and I) were experiencing with interaction and intercultural communication among students in our diverse classrooms. Educators were also experiencing difficulties in motivating students to work effectively in groups. The purpose of this paper was to seek solutions to these problems by exploring variations of the group oral assessment structure in a multilingual and multicultural context. Four phases of assessments were conducted at two tertiary institutions in South Africa using a combination of action research and a participatory approach. Not only did this study succeed in addressing the problems but it also revealed the added benefits of using an action research methodology.  相似文献   
977.
In order to tradeoff exploration/exploitation and inspired by cell genetic algorithm a cellshift crossover operator for evolutionary algorithm (EA) is proposed in this paper. The definition domain is divided into n-dimension cubic sub-domains (cell) and each individual locates at an ndimensional cube. Cell-shift crossover first exchanges the cell numbers of the crossover pair if they are in the different cells (exploration) and subsequently shift the first individual from its initial place to the other individual's cell place. If they are already in the same cell heuristic crossover (exploitation) is used. Cell-shift/heuristic crossover adaptively executes exploration/exploitation search with the vary of genetic diversity. The cell-shift EA has excellent performance in terms of efficiency and efficacy on ten usually used optimization benchmarks when comparing with the recent well-known FEP evolutionary algorithm.  相似文献   
978.
This paper studies identification of systems in which the system output is quantized, transmitted through a digital communication channel, and observed afterwards. The concept of the CR Ratio is introduced to characterize impact of communication channels on identification. The relationship between the CR Ratio and Shannon channel capacity is discussed. Identification algorithms are further developed when the channel error probability is unknown.  相似文献   
979.
Vertebrate thymosin-β4, RACK1 and HMGB are important molecules functioning in embryonic development and adult life. Here we report the expression patterns of amphioxus thymosin-β4, RACK1 and HMGB genes in tissues of adult amphioxus as revealed by RT-PCR and in situ hybridization. These three genes are all strongly expressed in the central nervous system and ovary, but differently expressed in other tissues including gut, testis, wheel organ, gill and endostyle.  相似文献   
980.
Accurate estimation of shape and motion variability of the heart has important clinical implications for heart disease diagnosis. In this paper, we describe a framework which performs simultaneous segmentation and motion analysis of the left ventricle from 3D cardiac images. The left ventricle is formulated as an anisotropic linear elastic body represented by a set of tetrahedrons constructed from sampling nodes. The elastic body is evolved by both internal force and external force, and the external force imposed on each node is an integration of edginess measure, shape coherence measure, prior distributions of the myocardial tissues and temporal driven measure. The displacement field and the segmentation result are simultaneously solved at the equilibrium state between the internal energy and the external energy. The experiment with 3D canine MR images illustrated its abilities and benefits.  相似文献   
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