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251.
室内装饰织物因其容易点燃、燃烧速度快、蔓延迅速等燃烧特性,对室内火灾的发展蔓延及火灾危害都有重要影响。运用锥形量热仪对棉麻、涤纶、帆布、泡纱、条绒等5种室内装饰织物的燃烧性能进行了实验研究,测量了室内装饰织物在不同热辐射条件下的燃烧特性,并对实验数据进行图像拟合,通过具体的实验数据和图像分析比较了5种室内装饰织物在不同热辐射条件下的点燃时间、热释放速率、质量损失速率、比消光面积及CO生成量。最后得出了各种织物的火灾危险性相对大小。  相似文献   
252.
伴随着“认知域”作战概念被引入军事领域,现代战场已经形成了物理域、信息域、认知域三大作战维度。认知域已经成为美国战略空间拓展的主要战场之一。按照习主席关于要打好意识形态领域“制脑权”战争的思想,更需要重视认知域的攻防,研究相关技术,才能在没有硝烟的战场上不落下风。  相似文献   
253.
Within a reasonable life‐testing time, how to improve the reliability of highly reliable products is one of the great challenges to today's manufacturers. By using a resolution III experiment together with degradation test, Tseng, Hamada, and Chiao (1995) presented an interesting case study of improving the reliability of fluorescent lamps. However, in conducting such an experiment, they did not address the problem of how to choose the optimal settings of variables, such as sample size, inspection frequency, and termination time for each run, which are influential to the correct identification of significant factors and the experimental cost. Assuming that the product's degradation paths satisfy Wiener processes, this paper proposes a systematic approach to the aforementioned problem. First, an intuitively appealing identification rule is proposed. Next, under the constraints of a minimum probability of correct decision and a maximum probability of incorrect decision of the proposed identification rule, the optimum test plan (including the determinations of inspection frequency, sample size, and termination time for each run) can be obtained by minimizing the total experimental cost. An example is provided to illustrate the proposed method. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 514–526, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10024  相似文献   
254.
In this paper, a single‐machine scheduling problem with weighted earliness and tardiness penalties is considered. Idle time between two adjacent jobs is permitted and due dates of jobs could be unequal. The dominance rules are utilized to develop a relationship matrix, which allows a branch‐and‐bound algorithm to eliminate a high percentage of infeasible solutions. After combining this matrix with a branching strategy, a procedure to solve the problem is proposed. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 760–780, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10039  相似文献   
255.
提出一种基于信息融合的分布式多舰纯方位跟踪算法 ,该算法采用时变采样间隔的修正增益推广卡尔曼滤波器 ,用多条舰艇的舰载电子侦察设备对海上多个运动辐射源目标进行分布式纯方位跟踪融合。计算机模拟结果表明 ,该算法能满足工程应用的要求  相似文献   
256.
燃气轮机的实时仿真及数据预处理   总被引:4,自引:2,他引:2  
讨论了燃气轮机实时仿真及相应的数据预处理方法 ,利用容积惯性法建立了某型燃气轮机的实时仿真模型 ,在 5 86PC实现了超实时仿真 ,仿真结果和试验数据相符  相似文献   
257.
从信息管理系统的模式出发,分析了系统的结构模式,并对由此产生的并发控制问题,应用时间戳法进行了分析处理,用触发器存储过程解决了对数据的随时更新问题。本系统以Sybase作为数据库,设计并实现了药库管理系统。  相似文献   
258.
数字化部队指挥网络系统效能评价模型   总被引:5,自引:0,他引:5  
以结构熵理论为基础,分析数字化部队作战指挥信息网络系统组织结构对系统内信息流的影响,从信息的角度对系统组织结构的有序度进行评价,引入信息流的时效和质量的概念,建立定量评价系统结构有序度计算的时效质量模型,结合系统数据传输业务效能的评价方法,形成作战指挥信息网络系统整体综合效能的评价模型。最后辅以实例。  相似文献   
259.
Discrete‐time queues with D‐MAP arrival process are more useful in modeling and performance analysis of telecommunication networks based on the ATM environment. This paper analyzes a finite‐buffer discrete‐time queue with general bulk‐service rule, wherein the arrival process is D‐MAP and service times are arbitrarily and independently distributed. The distributions of buffer contents at various epochs (departure, random, and prearrival) have been obtained using imbedded Markov chain and supplementary variable methods. Finally, some performance measures such as loss probability and average delay are discussed. Numerical results are also presented in some cases. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 345–363, 2003.  相似文献   
260.
We study the problems of scheduling a set of nonpreemptive jobs on a single or multiple machines without idle times where the processing time of a job is a piecewise linear nonincreasing function of its start time. The objectives are the minimization of makespan and minimization of total job completion time. The single machine problems are proved to be NP‐hard, and some properties of their optimal solutions are established. A pseudopolynomial time algorithm is constructed for makespan minimization. Several heuristics are derived for both total completion time and makespan minimization. Computational experiments are conducted to evaluate their efficiency. NP‐hardness proofs and polynomial time algorithms are presented for some special cases of the parallel machine problems. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 531–554, 2003  相似文献   
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