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1.
针对指挥控制资源部署问题,引入任务复杂度来定义决策实体的工作负载,并建立以最小化决策实体工作负载的均方根为目标的优化模型。针对传统的层次聚类法容易陷入局部最优,提出了一种变邻域搜索(Variable Neighborhood Search,VNS)和模拟退火(Simulated Annealing,SA)相结合的具有全局性的求解方法,使用VNS进行全局寻优,使用SA对VNS中的邻域进行局部寻优。最后通过一个联合作战案例的平台调度方案,验证了所提方法的优越性。  相似文献   

2.
This article presents two meta‐ranking models that minimize or nearly minimize violations of past game results while predicting future game winners as well as or better than leading current systems—a combination never before offered for college football. Key to both is the development and integration of a highly predictive ensemble probability model generated from the analysis of 36 existing college football ranking systems. This ensemble model is used to determine a target ranking that is used in two versions of a hierarchical multiobjective mixed binary integer linear program (MOMBILP). When compared to 75 other systems out‐of‐sample, one MOMBILP was the leading predictive system while getting within 0.64% of the retrodictive optimum; the other MOMBILP minimized violations while achieving a prediction total that was 2.55% lower than the best mark. For bowls, prediction sums were not statistically significantly different from the leading value, while achieving optimum or near‐optimum violation counts. This performance points to these models as potential means of reconciling the contrasting perspectives of predictiveness versus the matching of past performance when it comes to ranking fairness in college football. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 61: 17–33, 2014  相似文献   

3.
为了解决传统PID控制器在电动舵机系统设计中难以满足控制要求的问题,首先设计了一种规范化前馈-反馈控制系统,然后利用混沌优化算法和共轭梯度方法相结合的混合优化算法对前馈-反馈控制器参数进行了优化.仿真结果表明:基于混合优化算法的前馈-反馈控制器具有很好的动态和静态性能,增强了系统的稳定性和鲁棒性,降低了学习参数选择的盲目性和对经验的高度依赖性.  相似文献   

4.
In this article we consider a stochastic model for two products which have a single-period inventory structure and which can be used as substitutes for each other should the need arise. Substitution will occur with probability one, but at perhaps a different revenue level. We prove that the expected profit function is concave, allowing us to find optimal stocking levels for the two products. We compare optimum inventory levels for the case of single substitution with that where there is no substitution. It is demonstrated for the case of single substitution that total optimum order quantities can actually increase or decrease with the substitution revenue.  相似文献   

5.
A new approximate method is proposed for the economic design of control charts based on an estimate of the power of the control chart at optimality. Multiple linear regression is employed for the derivation of the approximate formula expressing the power of the control chart as a function of the model parameters. A simple optimization procedure is then used to determine the economic design of the control chart for the predicted value of the chart's detection power. The application of the new approach is illustrated through Duncan's models for variables control charts for processes subject to single and multiple assignable causes. Evaluation of the performance of the approximate method indicates that the approximate control chart design is very close to the exact optimum while its implementation requirements are reduced.  相似文献   

6.
探讨管道中高次波的有源控制问题.首先,对消声条件下的次级声源强度进行了理论分析,并对误差传声器的数目与位置进行了讨论.最后,进行了控制方截面管中(0,0)次波(平面波)和(1,0)次波的实验.结果表明,对管道中的高次波实施有源控制是完全可能的.  相似文献   

7.
介绍了微机控制瓦楞纸板同步剪切控制系统的设计研制。该系统由直流电机调速系统和单片微型计算机控制系统两大部分组成。直流调速系统采用线性二次型最优调节器方法设计,计算机控制系统采用单片微机双CPU技术。它是一个大功率高精度机电控制系统,具有响应速度快,剪切精度高,可靠性好,操作方便的特点。  相似文献   

8.
The individual and social optimum control policies for entry to an M/M//1 queue serving several classes of customers have been shown to be control-limit policies. The technique of policy iteration provides the social optimum policy for such a queue in a straightforward manner. In this article, the problem of finding the optimal control policy for the M/Ek/1 system is solved, thereby expanding the potential applicability of the solutions developed. The Markovian nature of the queueing system is preserved by considering the service as having k sequential phases, each with independent, identically distributed, exponential service times, through which a customer must pass to be serviced. The optimal policy derived by policy iteration for such a system is likely to be difficult to use because it requires knowledge of the number of phases rather than customers in the system when an arrival occurs. To circumvent this difficulty, a heuristic is used to find a good usable (implementable) solution. In addition, a mixed-integer program is developed which yields the optimal implementable solution when solved.  相似文献   

9.
A model is developed which may be used to determine the expected total cost of quality control per inspection lot under acceptance sampling by variables where several characteristics are to be simultaneously controlled. Optimization of the model is accomplished through the application of a conventional search procedure. The sensitivity of the model and the optimum solution to the shape of the underlying probability distributions is discussed and associated analyses are presented through an example.  相似文献   

10.
基于Matlab的齿轮传动可靠性优化设计   总被引:2,自引:0,他引:2  
在油料装备齿轮传动设计中,大多采用传统设计方法,存在人为误差大,计算精度低,难于找到符合需求的最优解等问题。提出了以齿轮传动可靠性为基础,将齿轮体积最小分解为中心距最小和齿宽最小双目标函数建立数学模型,利用Matlab程序实现齿轮传动的优化设计。实例证明,该方法在保证齿轮可靠度前提下可有效减小齿轮体积,并能更好适应产品要求。此方法简单、实用,易于设计人员掌握,并可应用于其它机械的优化设计。  相似文献   

11.
The purpose of this paper and the accompanying tables is to facilitate the calculation of constrained optimum order quantities and reorder points for an inventory control system where the criterion of optimality is the minimization of expected inventory holding, ordering, and time-weighted backorder costs. The tables provided in the paper allow the identification of the optimal solution when order quantities and/or reorder points are restricted to a set of values which do not include the unconstrained optimal solution.  相似文献   

12.
在工作寿命和修理时间之一服从一般的连续型分布,另一个服从指数分布的情形下讨论了单周期的备件存储问题,通过适当地划分系统的状态,利用Markov更新过程的理论进行了分析,建立了概率型模型,并由模型得到了最佳备件数的求法。  相似文献   

13.
伪谱法及其在飞行器轨迹优化设计领域的应用综述   总被引:3,自引:2,他引:1       下载免费PDF全文
采用伪谱法进行飞行器轨迹优化设计是近年来的热点研究方向,然而较全面地对各种方法进行综合分析的文献却很少。在对国内外相关文献进行系统研究的基础上,阐述了航空航天领域应用较为广泛的几种伪谱法的基本原理;归纳了伪谱法将连续最优控制问题转化为非线性规划问题的思路和具体步骤;总结了伪谱法在飞行器轨迹优化设计领域的应用情况;对伪谱法及其在飞行器轨迹优化设计领域应用的未来研究方向进行了分析。  相似文献   

14.
软件测试中的路径划分技术   总被引:1,自引:0,他引:1  
路径覆盖测试准则要优于其它已知的覆盖准则,但由于对一般的软件,路径数目太大,以至实际难以实现。路径划分是路径覆盖技术的一个折中方法。给定的程序P和给定模块的最大路径数目k,按就近原则,现给出了一种划分P的算法,使得每个划分后的模块所包含的路径数目都少于等于k。同时也给出了最佳划分的度量标准和最佳划分方法。  相似文献   

15.
The traditional approach to economic design of control charts is based on the assumption that a process is monitored using only a performance variable. If, however, the performance variable is costly to measure and a less expensive surrogate variable is available, the process may be more efficiently controlled by using both performance and surrogate variables. In this article we propose a model for economic design of a two-stage control chart which uses a highly correlated surrogate variable together with a performance variable. The process is assumed to be monitored by the surrogate variable until it signals out-of-control behavior, then by the performance variable until it signals out-of-control behavior or maintains in-control signals for a prespecified amount of time, and the two variables are used in alternating fashion. An algorithm based on the direct search method of Hooke and Jeeves [6] is used to find the optimum values of design parameters. The proposed model is applied to the end-closure welding process for nuclear fuel to compute the amount of reduction in cost compared with the current control procedure. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 958–977, 1999  相似文献   

16.
A model is developed taking into consideration all the costs (namely cost of sampling, cost of not detecting a change in the process, cost of a false indication of change, and the cost of readjusting detected changes) incurred when a production process, using an unscheduled setup policy, utilizes fraction-defective control charts to control current production. The model is based on the concept of the expected time between detection of changes calling for setups. It is shown that the combination of unscheduled setups and control charts can be utilized in an optimal way if those combinations of sample size, sampling interval, and extent of control limits from process average are used that provide the minimum expected total cost per unit of time. The costs of a production process that uses unscheduled setups in conjunction with the appropriate optimal control charts are compared to the costs of a production process that uses scheduled setups at optimum intervals in conjunction with its appropriate control charts. This comparison indicates the criteria for selecting production processes with scheduled setups using optimal setup intervals over unscheduled setups. Suggestions are made to evaluate the optimal process setup strategy and the accompanying optimal decision parameters, for any specific cost data, by use of computer enumeration. A numerical example for assumed cost and process data is provided.  相似文献   

17.
使用双层组合外套的船用液压联轴节的优化设计   总被引:2,自引:1,他引:1  
针对采用单层外套的传统船用液压联轴节扭矩提高受限的问题,提出了双层组合外套的结构形式,并详细分析了双层组合外套的应力分布并对其结构尺寸进行了优化,得到了双层组合外套的最佳分层原则及最佳过盈量。实例计算显示,采用双层组合外套的液压联轴节能传递更大的扭矩。  相似文献   

18.
为了研究活塞式磁通压缩发电机(P-MFCG)电枢内部涡流及周围的磁场分布,在Maxwell方程组的基础上,对电枢附近区域的磁场模型进行理论推导,得出电枢附近区域涡流场的控制方程。采用Ansoft有限元分析软件对应用于P-MFCG的柱状电枢上感应涡流、磁感应强度以及电枢所受电磁力的分布进行仿真分析,其结果对电枢的优化设计有重要参考意义。  相似文献   

19.
This article presents an optimum simple step-stress accelerated life test for the Weibull distribution under Type I censoring. It is assumed that a log-linear relationship exists between the Weibull scale parameter and the (possibly transformed) stress and that a certain cumulative exposure model for the effect of changing stress holds. The optimum plan—low stress and stress change time—is obtained, which minimizes the asymptotic variance of the maximum likelihood estimator of a stated percentile at design stress. For selected values of the design parameters, nomographs useful for finding the optimum plan are given, and the effects of errors in preestimates of the parameters are investigated. As an alternative to the simple step-stress test, a three-level compromise plan is proposed, and its performance is studied and compared with that of the optimum simple step-stress test. © 1993 John Wiley & Sons. Inc.  相似文献   

20.
合成分队动态武器目标分配协同决策模型   总被引:1,自引:0,他引:1  
针对合成分队地面作战特点,提出了一种动态武器目标分配的协同决策模型,该模型基于一种自适应决策中心的协同决策体系结构,以战场信息共享为核心,实现动态火力协同优化分配。提出了针对战场应急目标的一种快速火力分配方法,提高火力整体打击效率的火力适度分配优化方法,适应战场态势动态变化的anytime终止控制方法。仿真实例表明,该模型能够满足合成分队火力动态分配的需求,提高动态武器目标分配决策的合理性和科学性。  相似文献   

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