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141.
基于多通道通信技术的高速数据采集器的研制   总被引:3,自引:1,他引:2  
主要介绍应用多通道通信技术开发研制的高速数据采集器的功能特点 ,对实际研制和使用中的几个关键技术进行了较详细的分析讨论 .应用于流场测试试验的结果表明 ,该系统速度快、稳定性好、功能齐全且自动化程度高 .该系统具有的高精度非常适合于流场测试 ,能确保测试的准确性  相似文献   
142.
We consider the problem of scheduling a set of jobs with a common due-date on a single-machine where the release time of a job is related to the amount of resource consumed. The objective is to minimize the total resource consumption and the total tardiness. While the problem is strongly NP-hard in general, we discuss two different special cases for which special properties are identified and used to develop efficient pseudo-polynomial time algorithms. © 1995 John Wiley & Sons, Inc.  相似文献   
143.
简述了创造性思维教育的意义与目的,辨析了有关概念,提出了创造性思维教育的前提,详细讨论了创造性思维教育的有关措施.  相似文献   
144.
We consider the multitasking scheduling problem on unrelated parallel machines to minimize the total weighted completion time. In this problem, each machine processes a set of jobs, while the processing of a selected job on a machine may be interrupted by other available jobs scheduled on the same machine but unfinished. To solve this problem, we propose an exact branch‐and‐price algorithm, where the master problem at each search node is solved by a novel column generation scheme, called in‐out column generation, to maintain the stability of the dual variables. We use a greedy heuristic to obtain a set of initial columns to start the in‐out column generation, and a hybrid strategy combining a genetic algorithm and an exact dynamic programming algorithm to solve the pricing subproblems approximately and exactly, respectively. Using randomly generated data, we conduct numerical studies to evaluate the performance of the proposed solution approach. We also examine the effects of multitasking on the scheduling outcomes, with which the decision maker can justify making investments to adopt or avoid multitasking.  相似文献   
145.
The quick response (QR) system that can cope with demand volatility by shortening lead time has been well studied in the literature. Much of the existing literature assumes implicitly or explicitly that the manufacturers under QR can always meet the demand because the production capacity is always sufficient. However, when the order comes with a short lead time under QR, availability of the manufacturer's production capacity is not guaranteed. This motivates us to explore QR in supply chains with stochastic production capacity. Specifically, we study QR in a two-echelon supply chain with Bayesian demand information updating. We consider the situation where the manufacturer's production capacity under QR is uncertain. We first explore how stochastic production capacity affects supply chain decisions and QR implementation. We then incorporate the manufacturer's ability to expand capacity into the model. We explore how the manufacturer determines the optimal capacity expansion decision, and the value of such an ability to the supply chain and its agents. Finally, we extend the model to the two-stage two-ordering case and derive the optimal ordering policy by dynamic programming. We compare the single-ordering and two-ordering cases to generate additional managerial insights about how ordering flexibility affects QR when production capacity is stochastic. We also explore the transparent supply chain and find that our main results still hold.  相似文献   
146.
We study the competition problem of purchase and multiretrieval of perishable seasonal produce, where wholesalers purchase and stock their products in the first period, and then retrieve and sell them in subsequent periods. We first consider the duopoly case and assume that the prices are exogenous and fluctuate. In each period, after the price realization, the wholesalers retrieve some stock from their warehouses to satisfy their demands. One wholesaler's unsatisfied customers can switch to another and be satisfied by its left retrieved products. Any unsold retrieved stock has no salvage value and any unsatisfied demand is lost. The unretrieved stock is carried to the next period at a perishable rate. The wholesalers compete for the substitute demand by determining their own purchase and retrieval quantities. We show the existence and uniqueness of a pure-strategy Nash equilibrium, and that the Nash equilibrium strategy has the simple “sell-down-to” structure. We also consider the general N-person game and show the existence of the Nash equilibrium, and characterize the structure of the equilibrium strategy for the symmetric case. In addition, we consider the case with endogenous prices, and show that the problem reduces to a repeated newsvendor game with price and inventory competition. We derive the conditions under which a unique Nash equilibrium exists and characterize the equilibrium strategy. Finally, we conduct numerical studies to examine the impacts of the model parameters on the equilibrium outcomes and to generate managerial insights.  相似文献   
147.
交互式多模型目标跟踪的研究现状及发展趋势   总被引:7,自引:1,他引:6  
系统地介绍了交互式多模型算法在机动目标跟踪领域中的发展现状、发展方向及其与数据关联相结合进行目标跟踪的发展趋势.通过分析交互式多模型算法本身存在的问题,指出了一些改进方法的可行性与不足;进一步介绍了数据关联与交互式多模型算法结合进行目标跟踪的发展情况及取得的成果,并对以后与交互式模型相关的研究方向进行了探讨.  相似文献   
148.
建立了充分考虑液压装置动力学特性的车辆半侧非线性主动悬挂模型,并提出了线性二次型最优控制与非线性逐步后退法相结合的内外环控制方案。首先根据目标需求在外环设计二次型指标下的最优控制器;然后在内环利用逐步后退法处理因液压装置引入的非线性项。仿真结果表明,使用该设计方案的主动悬挂可以获得比被动悬挂优越的车辆性能。  相似文献   
149.
根据战斗部破片和HTK拦截器命中目标的条件,建立了这两种杀伤方式下命中目标时所需允许脱靶量的模型,并对不同特性的目标进行了仿真计算和对比分析.结果表明战斗部在拦截低速、弱机动大型目标时具有较好适用性,HTK则对各种性能的小型目标具有良好的适用性,综合来看,HTK受目标特性影响较小,更适用于通用型防空反导制导武器.  相似文献   
150.
歼击机空战占位的模糊神经网络方法   总被引:1,自引:0,他引:1  
在歼击机空战中 ,首先占据有利的攻击位置 ,是夺取空战胜利的重要保证 ,不论是近距离格斗 ,还是超视距空战均如此。在未来 2 1世纪信息战环境下的空战 ,为了减轻飞机员的负担 ,必须根据战场态势 ,利用智能化方法 ,为飞行员提供正确操纵飞机达到有利攻击位置的辅助决策指示。本文研究了先敌占位的模糊神经网络方法 ,仿真证明这种方法是有效的  相似文献   
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