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41.
潜艇电力推进装置的动态模型辨识 总被引:1,自引:1,他引:0
将系统辨识的方法应用到潜艇电力推进系统的动态特性的分析中 ,辨识算法采用递推增广矩阵法(RELS) ,并采用变遗忘因子 ,以改善系统的跟踪性能 .研究对象为一模拟电力推进机组 ,在实验数据的基础上建立了该系统励磁控制下的动态模型 . 相似文献
42.
就IDEF0方法在军事综合电子信息系统分析设计、系统升级与集成及仿真等方面的应用进行了深入探讨。由于IDEF0模型具有简单、全面且描述能力强等优点 ,使其在多个领域尤其在制造业中得到了广泛应用。军事综合电子信息系统是以活动为支撑 ,以信息为基础的复杂大系统 ,用IDEF0模型对其进行描述可以加深指挥人员和技术人员对系统的共同理解 ,从而提高系统开发的效率并提高系统的实用性。 相似文献
43.
Allocation of scarce common components to finished product orders is central to the performance of assembly systems. Analysis of these systems is complex, however, when the product master schedule is subject to uncertainty. In this paper, we analyze the cost—service performance of a component inventory system with correlated finished product demands, where component allocation is based on a fair shares method. Such issuing policies are used commonly in practice. We quantify the impact of component stocking policies on finished product delays due to component shortages and on product order completion rates. These results are used to determine optimal base stock levels for components, subject to constraints on finished product service (order completion rates). Our methodology can help managers of assembly systems to (1) understand the impact of their inventory management decisions on customer service, (2) achieve cost reductions by optimizing their inventory investments, and (3) evaluate supplier performance and negotiate contracts by quantifying the effect of delivery lead times on costs and customer service. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48:409–429, 2001 相似文献
44.
Fangruo Chen 《海军后勤学研究》2000,47(5):422-439
Consider a distribution system with a central warehouse and multiple retailers. Customer demand arrives at each of the retailers continuously at a constant rate. The retailers replenish their inventories from the warehouse which in turn orders from an outside supplier with unlimited stock. There are economies of scale in replenishing the inventories at both the warehouse and the retail level. Stockouts at the retailers are backlogged. The system incurs holding and backorder costs. The objective is to minimize the long‐run average total cost in the system. This paper studies the cost effectiveness of (R, Q) policies in the above system. Under an (R, Q) policy, each facility orders a fixed quantity Q from its supplier every time its inventory position reaches a reorder point R. It is shown that (R, Q) policies are at least 76% effective. Numerical examples are provided to further illustrate the cost effectiveness of (R, Q) policies. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 422–439, 2000 相似文献
45.
This paper develops and applies a nonparametric bootstrap methodology for setting inventory reorder points and a simple inequality for identifying existing reorder points that are unreasonably high. We demonstrate that an empirically based bootstrap method is both feasible and calculable for large inventories by applying it to the 1st Marine Expeditionary Force General Account, an inventory consisting of $20–30 million of stock for 10–20,000 different types of items. Further, we show that the bootstrap methodology works significantly better than the existing methodology based on mean days of supply. In fact, we demonstrate performance equivalent to the existing system with a reduced inventory at one‐half to one‐third the cost; conversely, we demonstrate significant improvement in fill rates and other inventory performance measures for an inventory of the same cost. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 459–478, 2000 相似文献
46.
针对船舶推进装置中柴油主机相继增压特性的优化问题,在理论分析的基础上,建立了基于准稳态假设的增压系统能量平衡模型.对相继增压系统的稳、动态特性进行了分析,讨论了相继增压系统的特性优化问题,为主机采用相继增压技术的柴油机推进装置的性能优化、控制策略的制订提供了理论依据. 相似文献
47.
对时滞控制作用下的参数激励van der Pol-Duffing方程进行了研究,着重研究了时滞参数对该类参数激励系统的1/2亚谐共振-主参数共振分叉响应控制。首先采用摄动法从理论上推导出时滞动力系统的分叉响应方程,再采用数值模拟的方法研究了时滞参数对系统分叉响应的影响。研究结果表明,适当选取时滞参数,不仅可以改变分叉响应曲线的拓扑形态,还可以平移分叉响应曲线,即使其分叉提前或滞后,还能同时满足这两种要求。 相似文献
48.
49.
C4ISR(Command、Control、Communication、Computer、Intelligence、Surveillance and Reconnaissance)系统开发的仿真模型涉及多个应用领域,具有多粒度、阶段相关性等的特性.本文提出了C4ISR系统开发的仿真模型体系,给出了仿真模型的规范化描述.... 相似文献
50.
The laser technology has made remarkable progress over the past couple of decades.It is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military weapons.Owing to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive roles.In modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground targets.Additionally,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial applications.Moreover,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical operations.Furthermore,the developments in space sciences and laser technology have given syner-gistic potential outcomes to use laser systems in space operations.This paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in space.Additionally,a detailed analysis has been done on recent advancements of the laser technology for target indicators and range-finders.It also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and ad-vancements in the domain of high energy directed laser weapons that have revolutionized the evolving military battlefield.Besides offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains. 相似文献