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821.
基于改进量子遗传算法的有源噪声控制方法 总被引:1,自引:0,他引:1
提出了一种基于改进量子遗传算法的格型IIR滤波器结构的有源噪声控制方法——改进的量子遗传算法(IQGA)。其核心是在对量子门更新过程进行改进的基础上,引入群体灾变和自适应搜索网格的策略。IQGA不仅收敛速度快,还可以改变基本遗传算法(GA)的局部搜索能力,克服基本遗传算法存在的未成熟收敛问题。仿真结果表明,该算法可以有效地实现噪声控制。 相似文献
822.
823.
PAC-3反导系统作战效能研究 总被引:3,自引:0,他引:3
为评估PAC-3反导系统的作战效能,通过分析影响该系统作战效能的因素,构建了一个评价指标体系,并利用幂函数法建立了定量评估模型。结合系统的作战性能参数,对PAC-3反导系统的作战效能进行了评估,为研究其作战提供了参考依据。 相似文献
824.
We study the problem of capacity exchange between two firms in anticipation of the mismatch between demand and capacity, and its impact on firm's capacity investment decisions. For given capacity investment levels of the two firms, we demonstrate how capacity price may be determined and how much capacity should be exchanged when either manufacturer acts as a Stackelberg leader in the capacity exchange game. By benchmarking against the centralized system, we show that a side payment may be used to coordinate the capacity exchange decisions. We then study the firms' capacity investment decisions using a biform game framework in which capacity investment decisions are made individually and exchange decisions are made as in a centralized system. We demonstrate the existence and uniqueness of the Nash equilibrium capacity investment levels and study the impact of firms' share of the capacity exchange surplus on their capacity investment levels.© 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
825.
Burn‐in is a widely used method to improve the quality of products or systems after they have been produced. In this paper, we study burn‐in procedure for a system that is maintained under periodic inspection and perfect repair policy. Assuming that the underlying lifetime distribution of a system has an initially decreasing and/or eventually increasing failure rate function, we derive upper and lower bounds for the optimal burn‐in time, which maximizes the system availability. Furthermore, adopting an age replacement policy, we derive upper and lower bounds for the optimal age parameter of the replacement policy for each fixed burn‐in time and a uniform upper bound for the optimal burn‐in time given the age replacement policy. These results can be used to reduce the numerical work for determining both optimal burn‐in time and optimal replacement policy. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
826.
We consider a mixed‐model assembly line (MMAL) comprised a set of workstations and a conveyor. The workstations are arranged in a serial configuration. The conveyor moves at a constant speed along the workstations. Initial units belonging to different models are successively fed onto the conveyor, and they are moved by the conveyor to pass through the workstations to gradually generate final products. All assembling tasks are manually performed with operation times to be stochastic. An important performance measure of MMALs is overload times that refer to uncompleted operations for operators within their work zones. This paper establishes a method to analyze the expected overload times for MMALs with stochastic operation times. The operation processes of operators form discrete time nonhomogeneous Markov processes with continuous state spaces. For a given daily production schedule, the expected overload times involve in analyzing the Markov processes for finite horizon. Based on some important properties of the performance measure, we propose an efficient approach for calculating the expected overload times. Numerical computations show that the results are very satisfactory. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
827.
研究了一种模糊控制方法 ,并用于分级燃烧循环液体火箭发动机变工况过程的反馈控制。仿真研究表明 :在抑制参数抖振方面 ,模糊控制优于一般的变结构控制 相似文献
828.
针对参考卫星运行于圆轨道的编队飞行,分析了J2项摄动的影响.在此基础上提出了一种方法,通过调整环绕卫星的半长轴,大大减小了J2项摄动对编队飞行的破坏作用.此外,基于冲量假设估计了编队保持的代价.数值结果表明,调整长半轴的卫星编队可以长期保持,节省了大量的控制燃料. 相似文献
829.
830.
虚拟现实与仿真技术在火控系统中的应用 总被引:7,自引:0,他引:7
简述了虚拟现实(VR)的概念、基本特征及其系统体系结构,探讨了虚拟现实(VR)与系统仿真的关系,介绍了其在火控系统中的应用. 相似文献