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361.
装备可计量性的理论方法研究对提高装备的计量保障水平具有重要意义。针对国内缺乏装备可计量性模型的现状,提出了可计量性分析设计的多信号模型方法。系统总结了可计量性多信号模型的基本理论,详细介绍了在单超差假设及不考虑组元可靠性、计量时间和费用影响下的超差检查用检定和超差定位用检定操作优选算法以及计量策略制定方法。建立了信号产生系统多信号模型,给出了超差-检定相关性矩阵,分析了信号产生系统的计量检定树,结论与信号产生系统实际检定方法相符,实例证明,此方法合理有效。 相似文献
362.
采用MSC.Patran参数化建模和遗传算法进行包带式星箭连接结构优化设计。首先给出了包带连接结构二维轴对称模型优化设计过程中涉及的V形卡块刚度等效、包带预紧力模拟和载荷施加方法,以及强度和刚度约束条件、优化目标等内容;然后以某直径为3m的包带连接结构为例进行了优化设计,并分析了对接框内延伸段长度和端头高度对应力及变形的影响;最后建立三维有限元模型进行静力分析。结果表明(1)该方法适用于包带连接结构的优化设计;(2)增加对接框内延伸段长度和端头高度能够提高整体连接刚度;(3)三维有限元模型与轴对称模型计算结果一致,验证了轴对称模型分析方法的正确性,以及V形卡块等效和预紧力模拟方法的有效性。 相似文献
363.
绳慧 《军械工程学院学报》2013,(5):55-62
粒子滤波在基于图像序列的目标跟踪中获得了广泛应用.针对其计算量较大的问题,提出一种迭代卡尔曼粒子滤波算法,将非线性跟踪问题分解为线性子结构的全局状态空间模型和非线性子结构的局部状态空间模型,利用粒子滤波在卡尔曼滤波估计值的局部范围内搜索目标,逼近真实目标状态.将实验结果与粒子滤波进行比较,结果表明,迭代卡尔曼粒子滤波减少了粒子数,降低了计算量,能够对高机动目标进行实时稳定的跟踪. 相似文献
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366.
针对传统动力装置设计方法中存在计算复杂、动态性能难以计算等问题,提出利用动力装置仿真系统来设计船舶动力装置的方法。首先,利用模块化建模原理建立了动力装置各组成部件的数学模型,然后利用C 语言编写了各模型的仿真程序,并建立了动力装置仿真系统。利用该仿真系统对某型船舶的全燃动力装置进行了详细设计,设计过程及结果表明,采用仿真系统来设计动力装置可以准确计算动力装置的动态性能,同时对动力装置各部件的性能参数进行优化。 相似文献
367.
靳威 《中国人民武装警察部队学院学报》2007,23(6):46-48
随着城市的发展和建筑水平的提高,对消防设计提出了越来越高的要求,防火分区的设计尤其重要。针对某高层通讯大厦的消防设计实例进行分析,运用性能化设计方法,探讨利用防火玻璃解决防火分区超大的技术办法。 相似文献
368.
In this article, we consider a multi‐product closed‐loop supply chain network design problem where we locate collection centers and remanufacturing facilities while coordinating the forward and reverse flows in the network so as to minimize the processing, transportation, and fixed location costs. The problem of interest is motivated by the practice of an original equipment manufacturer in the automotive industry that provides service parts for vehicle maintenance and repair. We provide an effective problem formulation that is amenable to efficient Benders reformulation and an exact solution approach. More specifically, we develop an efficient dual solution approach to generate strong Benders cuts, and, in addition to the classical single Benders cut approach, we propose three different approaches for adding multiple Benders cuts. These cuts are obtained via dual problem disaggregation based either on the forward and reverse flows, or the products, or both. We present computational results which illustrate the superior performance of the proposed solution methodology with multiple Benders cuts in comparison to the branch‐and‐cut approach as well as the traditional Benders decomposition approach with a single cut. In particular, we observe that the use of multiple Benders cuts generates stronger lower bounds and promotes faster convergence to optimality. We also observe that if the model parameters are such that the different costs are not balanced, but, rather, are biased towards one of the major cost categories (processing, transportation or fixed location costs), the time required to obtain the optimal solution decreases considerably when using the proposed solution methodology as well as the branch‐and‐cut approach. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
369.
A cycle time‐throughput (CT‐TH) curve, which quantifies the relationship of long‐run average cycle time to throughput rate, plays an important role in strategic planning for manufacturing systems. In this paper, a nonlinear regression metamodel supported by queueing theory is developed to represent the underlying CT‐TH curve implied by a manufacturing simulation model. To estimate the model efficiently, simulation experiments are built up sequentially using a multistage procedure. Extensive numerical experiments are presented to demonstrate the effectiveness of the proposed procedure. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
370.
The existing product line design literature devotes little attention to the effect of demand uncertainty. Due to demand uncertainty, the supply‐demand mismatch is inevitable which leads to different degrees of lost sales depending on the configuration of product lines. In this article, we adopt a stylized two‐segment setup with uncertain market sizes and illustrate the interplay between two effects: risk pooling that mitigates the impact of demand uncertainty and market segmentation that facilitates consumer differentiation. Compared to downward substitution, inducing bidirectional substitution through product line decisions including quality levels and prices can yield greater risk pooling effects. However, we show that the additional benefit from the risk pooling effect cannot compensate for the reduced market segmentation effect. We demonstrate that the presence of demand uncertainty can reduce the benefit of market segmentation and therefore the length of product lines in terms of the difference between products. We also propose three heuristics that separate product line and production decisions; each of these heuristics corresponds to one particular form of demand substitution. Our numerical studies indicate that the best of the three heuristics yields performance that is close to optimality. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 143–157, 2015 相似文献