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101.
用遗传算法实现雷达网目标分配 总被引:2,自引:0,他引:2
通过对雷达网目标分配问题的深入研究,建立了数学模型.为了获得发现概率最大的目标分配方案,引入了遗传算法来对模型求解,并给出了实现的步骤和方法.最后经过验证,证明该方法应用在雷达网目标分配问题上切实可行. 相似文献
102.
A system reliability is often evaluated by individual tests of components that constitute the system. These component test plans have advantages over complete system based tests in terms of time and cost. In this paper, we consider the series system with n components, where the lifetime of the i‐th component follows exponential distribution with parameter λi. Assuming test costs for the components are different, we develop an efficient algorithm to design a two‐stage component test plan that satisfies the usual probability requirements on the system reliability and in addition minimizes the maximum expected cost. For the case of prior information in the form of upper bounds on λi's, we use the genetic algorithm to solve the associated optimization problems which are otherwise difficult to solve using mathematical programming techniques. The two‐stage component test plans are cost effective compared to single‐stage plans developed by Rajgopal and Mazumdar. We demonstrate through several numerical examples that our approach has the potential to reduce the overall testing costs significantly. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 95–116, 2002; DOI 10.1002/nav.1051 相似文献
103.
电磁干扰条件下解决断续航路预测问题对防空兵有效抗击空中目标至关重要。针对包络灰预测方法预测精度较低和Verhulst灰色预测模型计算过程复杂的情况,提出了预测航路的分形方法。在分形理论的基础上,研究了其用于目标断续航路预测的基本思路,建立了基于分形的目标航路预测模型,并对模型进行了求解。最后,利用建立的分形模型对雷达丢失目标后的目标航路进行了预测,通过实例体现了分形方法在用于航路预测时的准确性、灵活性和易实现等特点。结果表明,用该法对断续目标航路的预测具有一定的借鉴意义。 相似文献
104.
基于模糊匈牙利算法的炮兵火力单位分配问题 总被引:1,自引:0,他引:1
发挥诸火力单位的整体协调优势,寻求在给定约束条件下总的射击效果最好的分配方案,是火力单位最优分配的基本任务.匈牙利算法是求解传统的指派问题的一种较好的方法,运用模糊匈牙利算法在决策过程中将主观因素与客观因素有机地结合起来,解决火力单位分配方案决策中多指标指派问题,从而可以有效地解决炮兵火力单位分配最优化问题. 相似文献
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Anja Bettina Schmiedt;Erhard Cramer; 《海军后勤学研究》2024,71(3):389-415
The model of adaptive progressive Type-II censoring introduced by Ng et al. (2009) (referred to as Ng–Kundu–Chan model) is extended to allow switching from a given initial censoring plan R$$ mathcal{R} $$ to any arbitrary given plan S$$ mathcal{S} $$ of the same length. In this generalized model, the joint distribution of the failure times and the corresponding likelihood function is derived. It is illustrated that the computation of maximum likelihood and Bayesian estimates are along the same lines as for standard progressive Type-II censoring. However, the distributional properties of the estimators will usually be different since the censoring plan actually applied in the (generalized) Ng–Kundu–Chan model is random. As already mentioned in Cramer and Iliopoulos (2010), we directly show that the normalized spacings are independent and identically exponentially distributed. However, it turns out that the spacings themselves are generally dependent with mixtures of exponential distributions as marginals. These results are used to study linear estimators. Finally, we propose an algorithm for generating random numbers in the generalized Ng–Kundu–Chan model and present some simulation results. The results obtained also provide new findings in the original Ng–Kundu–Chan model; the corresponding implications are highlighted. 相似文献
107.
In progressive censoring, items are removed at certain times during the life test. Commonly, it is assumed that the removed items are used for further testing. In order to take into account information about these additional testing in inferential procedures, we propose a two‐step model of stage life testing with one fixed stage‐change time which incorporates information about both the removed items (further tested under different conditions) and those remaining in the current life test. We show that some marginal distributions in our model correspond either to progressive censoring with a fixed censoring time or to a simple‐step stress model. Furthermore, assuming a cumulative exposure model, we establish exact inferential results for the distribution parameters when the lifetimes are exponentially distributed. An extension to Weibull distributed lifetimes is also discussed. 相似文献
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