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951.
针对发动机及其部件试验传感器数据证实的多源证据融合问题,描述了建立贝叶斯信度网络的方法,给出了传感器状态和检验关系式不确定性信息表达方法,发展了自动建立贝叶斯信度网络、计算可信度概率及更新网络的算法;给出了贝叶斯信度网络方法在模型发动机上的应用示例。  相似文献   
952.
被动传感器由于采用无源探测,而且制造成本低,体积小,在战场环境中将采用并配置大量的被动传感器来检测目标.不论是主动还是被动式传感器,在实际应用中均存在资源优化配置问题.针对被动传感器的具体应用模型,采取了若干合理近似,得到了在"OR"融合检测条件下,基于最大检测概率的被动传感器优化配置密度计算公式.  相似文献   
953.
This paper considers a two-agent scheduling problem with linear resource-dependent processing times, in which each agent has a set of jobs that compete with that of the other agent for the use of a common processing machine, and each agent aims to minimize the weighted number of its tardy jobs. To meet the due date requirements of the jobs of the two agents, additional amounts of a common resource, which may be in discrete or continuous quantities, can be allocated to the processing of the jobs to compress their processing durations. The actual processing time of a job is a linear function of the amount of the resource allocated to it. The objective is to determine the optimal job sequence and resource allocation strategy so as to minimize the weighted number of tardy jobs of one agent, while keeping the weighted number of tardy jobs of the other agent, and the total resource consumption cost within their respective predetermined limits. It is shown that the problem is -hard in the ordinary sense, and there does not exist a polynomial-time approximation algorithm with performance ratio unless ; however it admits a relaxed fully polynomial time approximation scheme. A proximal bundle algorithm based on Lagrangian relaxation is also presented to solve the problem approximately. To speed up convergence and produce sharp bounds, enhancement strategies including the design of a Tabu search algorithm and integration of a Lagrangian recovery heuristic into the algorithm are devised. Extensive numerical studies are conducted to assess the effectiveness and efficiency of the proposed algorithms.  相似文献   
954.
主要对电传动系统永磁同步电机进行了设计和仿真,首先对电传动和所采用永磁同步电动机进行了概述,给出了电机的基本参数要求,并在这些参数基础上对电机结构进行了初步设计,然后运用Simulink对永磁同步电机进行了建模仿真,获得了较为理想的结果。  相似文献   
955.
为解决控制系统中角度位置信号实时测量、分析手段缺乏的问题,设计基于USB技术的便携式角度位置数据采集仪。该设计采用专用轴角转换模块、高性能单片机和USB接口芯片为硬件平台,通过采集分析软件的开发,实现了多通道组合轴角数据采集、显示和存储功能。单片机模拟DMA总线时序技术有效提高数据传输速率,较好地满足了实际测量的需要。  相似文献   
956.
数据仓库技术用于C4ISR系统效能评估   总被引:2,自引:0,他引:2  
建立了C4ISR系统效能评估的指标体系,根据对整个C4ISR系统进行效能评估需要数据的海量、非结构等特点,建立了一个数据仓库系统。数据仓库系统以嵌套的数据集市为基础,采用了数据采集加工、联机分析处理、数据挖掘等技术,加快各种数据的运算速度以及提高系统效能评估的准确性。  相似文献   
957.
The reoptimization procedure within the shifting bottleneck (SB) involves reevaluation of all previously scheduled toolgroup subproblems at each iteration of the SB heuristic. A real options analysis (ROA) model is developed to value the option to reoptimize in the SB heuristic, such that reoptimization only occurs when it is most likely to lead to a schedule with a lower objective function. To date, all ROA models have sought to value options financially (i.e., in terms of monetary value). The ROA model developed in this paper is completely original in that it has absolutely no monetary basis. The ROA methodologies presented are shown to greatly outperform both full and no reoptimization approaches with respect to both computation time and total weighted tardiness. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
958.
We consider the scheduling problem in a make‐to‐stock queue with two demand classes that can be differentiated based on their variability. One class experiences Poisson arrivals and the other class experiences hyperexponential renewal arrivals. We provide an exact analysis of the case where the demand class with higher variability is given non‐preemptive priority. The results are then used to compare the inventory cost performance of three scheduling disciplines, first‐come first‐serve and priority to either class. We then build on an existing dynamic scheduling heuristic to propose a modification that works well for our system. Extensions of the heuristic to more than two classes and to the case where demand state is known are also discussed. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.  相似文献   
959.
The quay crane scheduling problem consists of determining a sequence of unloading and loading movements for cranes assigned to a vessel in order to minimize the vessel completion time as well as the crane idle times. Idle times originate from interferences between cranes since these roll on the same rails and a minimum safety distance must be maintained between them. The productivity of container terminals is often measured in terms of the time necessary to load and unload vessels by quay cranes, which are the most important and expensive equipment used in ports. We formulate the quay crane scheduling problem as a vehicle routing problem with side constraints, including precedence relationships between vertices. For small size instances our formulation can be solved by CPLEX. For larger ones we have developed a branch‐and‐cut algorithm incorporating several families of valid inequalities, which exploit the precedence constraints between vertices. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
960.
多自治空间数据源的k邻近查询处理   总被引:1,自引:0,他引:1       下载免费PDF全文
多自治空间数据源的k邻近查询处理在空间信息领域具有广泛的应用。综合分析比较现有的查询处理算法,研究并提出了多自治空间数据源环境下k邻近查询处理框架及其实现算法。实验结果表明,所提出的算法能有效地减少k邻近查询处理系统的数据传输量,减少了系统响应时间。  相似文献   
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