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991.
992.
基于Agent的卫星航天系统建模与仿真方法研究 总被引:1,自引:0,他引:1
使用基于Agent的建模与仿真(ABMS)研究卫星航天系统,以解决对其总体功能和应用效能进行评估的问题。首先,介绍了卫星航天系统的概念和组成,并对其复杂性作了分析。然后,从应用角度介绍了Agent模型所应具备的特性,并指出了ABMS在传统建模与仿真方法的基础上还需开展的额外工作。最后,以一个火灾卫星系统为例进行了实现,证明了此方法应用的可行性和有效性。 相似文献
993.
在深入研究异构数据库在模式和SQL语法等方面差异的基础上,设计了可扩展的冲突检查和处理机制,通过对潜在的冲突元素进行针对性调整避免模式冲突的不利影响.同时为了向上层应用程序屏蔽数据库移植中的模式调整,提出了在运行期间动态调整操作请求来保证数据库操作的准确性. 相似文献
994.
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
995.
Conflict analysis approaches for investigating attitudes and misperceptions in the War of 1812 总被引:1,自引:0,他引:1
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
996.
Jinwang LIU Dongmei LI Xiaosong CHEN 《系统科学与复杂性》2007,20(4):610-613
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
997.
一种改进的单纯形算法 总被引:1,自引:0,他引:1
针对无约束函数最优化问题,提出了一种能有效加快收敛速度的改进单纯形算法。在N-M单纯形算法的基础上,利用目标函数值的信息对反射中心重新定位,使反射方向更靠近目标函数最优值的方向,提高了搜索效率。函数寻优的对比测试结果表明,改进算法明显提高了单纯形算法的收敛速度和寻优质量。 相似文献
998.
UHF surface velocities radar is developed based on the successful ocean state measuring and analyzing radar system. The design method for UHF radar system is presented. It is designed to operate at UHF channel, and the transmit power is under 5W. Maximum range of field test over fresh water can be a kilometer. The field tests at Tangsun River and at Majiatan and Gaohazhou proved that USVR System can be used successfully. 相似文献
999.
Daniel S. Yeung Wing W. Y. Ng Aki P. F. Chan Patrick P. K. Chan Michael Firth Eric C. C. Tsang 《系统科学与系统工程学报(英文版)》2007,16(2):166-180
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
1000.
Penny Singh 《Systemic Practice and Action Research》2007,20(4):293-304
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