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991.
基于最大互信息指标的对偶控制研究 总被引:1,自引:0,他引:1
针对参数未知但恒定的随机系统, 研究了基于最大互信息指标的对偶控制. 运用了Kalman滤波器估计随机系统未知参数的方法; 研究了最大互信息指标所具有的对偶特性, 即跟踪理想的目标以及探测未知参数的不确定性; 采用了两级优化算法获得次优对偶控制律. 算例验证了此算法的有效性和可行性. 相似文献
992.
W. Hui P.J.-H. Hu † T.H.K. Clark ‡ K.Y. Tam‡ & J. Milton§ 《Journal of Computer Assisted Learning》2008,24(3):245-259
Abstract A field experiment compares the effectiveness and satisfaction associated with technology-assisted learning with that of face-to-face learning. The empirical evidence suggests that technology-assisted learning effectiveness depends on the target knowledge category. Building on Kolb's experiential learning model, we show that technology-assisted learning improves students' acquisition of knowledge that demands abstract conceptualization and reflective observation but adversely affects their ability to obtain knowledge that requires concrete experience. Technology-assisted learning better supports vocabulary learning than face-to-face learning but is comparatively less effective in developing listening comprehension skills. In addition, according to empirical tests, perceived ease of learning and learning community support significantly predict both perceived learning effectiveness and learning satisfaction. Overall, the results support our hypotheses and research model and suggest instructors should consider the target knowledge when considering technology-assisted learning options or designing a Web-based course. In addition, a supportive learning community can make technology-assisted learning easier for students and increase their learning satisfaction. 相似文献
993.
Scanning Depth of Route Panorama Based on Stationary Blur 总被引:1,自引:0,他引:1
This work achieves an efficient acquisition of scenes and their depths along long streets. A camera is mounted on a vehicle
moving along a straight or a mildly curved path and a sampling line properly set in the camera frame scans the 1D images over
scenes continuously to form a 2D route panorama. This paper proposes a method to estimate the depth from the camera path by
analyzing a phenomenon called stationary blur in the route panorama. This temporal blur is a perspective effect in parallel
projection yielded from the sampling slit with a physical width. We analyze the behavior of the stationary blur with respect
to the scene depth, vehicle path, and camera properties. Based on that, we develop an adaptive filter to evaluate the degree
of the blur for depth estimation, which avoids error-prone feature matching or tracking in capturing complex street scenes
and facilitates real time sensing. The method also uses much less data than the structure from motion approach so that it
can extend the sensing area significantly. The resulting route panorama with depth information is useful for urban visualization,
monitoring, navigation, and modeling. 相似文献
994.
Infonorma is a multi-agent system that provides its users with recommendations of legal normative instruments they might be
interested in. The Filter agent of Infonorma classifies normative instruments represented as Semantic Web documents into legal
branches and performs content-based similarity analysis. This agent, as well as the entire Infonorma system, was modeled under
the guidelines of MAAEM, a software development methodology for multi-agent application engineering. This article describes
the Infonorma requirements specification, the architectural design solution for those requirements, the detailed design of
the Filter agent and the implementation model of Infonorma, according to the guidelines of the MAAEM methodology. 相似文献
995.
首先介绍了工作流和工作流管理系统的定义,阐述了网格工作流和军事信息网格的研究现状.其次研究了网格工作流的调度模型并分析了网格工作流调度过程,通过将工作流的思想应用到军事信息网格系统中,给出了基于网格工作流的军事信息网格系统总体设计架构,并对架构中的各个组成模块进行了研究. 相似文献
996.
David K. Smith 《International Transactions in Operational Research》2008,15(2):121-150
There is considerable interest in the potential for using operational research (O.R.) in developing countries. One sign of this is the formation of new societies for O.R. scientists in countries and regions where no such society had existed. Since 2003, such societies have been formed in several parts of Africa. This paper focuses on West Africa, and presents a bibliography of papers relating to applications of O.R. in the nations of this part of the continent. The paper describes the way in which the bibliography was collated and discusses the overall picture that the list of papers presents of the state of O.R. in the 18 countries that are considered. 相似文献
997.
998.
网格应用程序执行时间预测系统 总被引:2,自引:0,他引:2
为了合理利用网格资源和改进应用程序的执行性能,需要对应用程序的执行时间进行实时预测,为任务调度系统和网格用户提供调度依据.本文工作建立了执行时间预测系统,周期性的产生预测信息并转换为统一格式注册到网格信息服务中.本文使用资源映射方法预测应用程序执行时间,并且设计一组实验测试系统性能.实验结果表明,本系统能够低开销,灵敏地预测执行时间,并且预测误差较小. 相似文献
999.
持续审计(CA)研究综述 总被引:4,自引:0,他引:4
持续审计(Continuous Auditing,CA)是目前计算机辅助审计领域中的一个研究前沿问题.本文对CA的研究进行了分析、比较和展望.首先分析了CA的内涵.然后,对CA的相关研究进行了分类:(1)技术实现方法,分成嵌入式和分离式两种;(2)理论分析;(3)应用于CA的关键技术,并根据该分类对CA的研究分别进行了分析.最后,总结了本文的工作,并对将来CA的研究做了展望. 相似文献
1000.