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991.
Wang Yongzhong 《国防科技大学学报》1995,17(3):95-103
ACOMPLEXOFTWOOPTIMIZATIONIDEASINOPTICALAUTOMATICDESIGNWangYongzhong(DepartmentofAppliedPhysics,NUDT,Changsha,410073)Abstract:... 相似文献
992.
本文从结构材料、结构形式、非线性分析、组合壳体和端盖强度以及结构的减振降噪等方面论述了潜艇结构强度研究的新近进展,并指出了今后的研究方向。 相似文献
993.
讨论了一个人机瞄系统的非线性分析设计。首先建立了人机瞄系统的非线性模型,然后采用反馈线性化方法,利用状态反馈,完全抵消了非线性因素对系统输出的影响,实现了系统输入-输出的严格线性关系和解耦控制,再利用线性系统方法,进行了系统的极点配置,使系统具有希望的跟踪性能,最后提出有待于深入研究的内容。 相似文献
994.
分析了目前国际上有关静电屏蔽性能测试的标准方法,针对我国目前缺少与国军标GJB2605-96配套的测试装置,作者参照美国电子工业协会标准EIA-541研制了一套静电屏蔽性能测试装置,并将此与美制静电屏蔽测试表ACL-500进行了对比实验,结果表明:在试验基板接地与不接地的两种情况下,试样内感应的峰值电压相差很大;试样的尺寸大小对测试结果影响不大;为了保证所测试的结果具有可比性,必须保持电容探头离试样袋口相等的距离。 相似文献
995.
采用普遍的方法导出了压阻法测试电路中端接电阻的计算公式,并从实验上进行了验证。 相似文献
996.
利用了谢弗-登普斯特方法讨论了两重假设下的多传感器信息融合问题。各个传磁器报告目标存在或目标不存在,所有的传感器报告都传输到信息融合中心,在这里利用了谢弗-登普斯特的组合法则,得到了信息融合中心的最终决策规则,并同多传感器信息融合的L-R试验方法进行了比较。 相似文献
997.
杨润泽 《军械工程学院学报》1994,(2)
本文提出利用增广加权范数把多目标优化问题转化为标量优化问题,证明了转化后的问题与原问题完全等价,同时给出了目标函数值与权系数的关系,建立了以目标函数值作为交互媒介的多目标优化方法,最后给出了应用该方法的一个实例。 相似文献
998.
In the past several decades, many ranking‐and‐selection (R&S) procedures have been developed to select the best simulated system with the largest (or smallest) mean performance measure from a finite number of alternatives. A major issue to address in these R&S problems is to balance the trade‐off between the effectiveness (ie, making a correct selection with a high probability) and the efficiency (ie, using a small total number of observations). In this paper, we take a frequentist's point of view by setting a predetermined probability of correct selection while trying to reduce the total sample size, that is, to improve the efficiency but also maintain the effectiveness. In particular, in order to achieve this goal, we investigate combining various variance reduction techniques into the fully sequential framework, resulting in different R&S procedures with either finite‐time or asymptotic statistical validity. Extensive numerical experiments show great improvement in the efficiency of our proposed procedures as compared with several existing procedures. 相似文献
999.
Ranking is a common task for selecting and evaluating alternatives. In the past few decades, combining rankings results from various sources into a consensus ranking has become an increasingly active research topic. In this study, we focus on the evaluation of rank aggregation methods. We first develop an experimental data generation method, which can provide ground truth ranking for alternatives based on their “inherent ability.” This experimental data generation method can generate the required individual synthetic rankings with adjustable accuracy and length. We propose characterizing the effectiveness of rank aggregation methods by calculating the Kendall tau distance between the aggregated ranking and the ground truth ranking. We then compare four classical rank aggregation methods and present some useful findings on the relative performances of the four methods. The results reveal that both the accuracy and length of individual rankings have a remarkable effect on the comparison results between rank aggregation methods. Our methods and results may be helpful to both researchers and decision‐makers. 相似文献
1000.
Satellite constellation design for forest fire monitoring via a stochastic programing approach 下载免费PDF全文
There is significant value in the data collected by satellites during and after a natural disaster. The current operating paradigm in practice is for satellites to passively collect data when they happen to fly over a disaster location. Conversely, this article considers the alternative approach of actively maneuvering satellites to fly directly overhead of the disaster site on a routine basis. Toward this end, we seek to compute a satellite constellation design that minimizes the expected maneuver costs for monitoring an unknown forest fire. In this article, we present a 2‐stage stochastic programing model for this problem as well as a accelerated L‐shaped decomposition approach. A comparison between our approach and the current operating paradigm indicates that our solution provides longer duration data collections and a greater number of data collections. Analysis also shows that our proposed solution is robust over a wide array of scenarios. 相似文献