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111.
针对多约束条件的无人机航路规划评价方法缺乏合理性和动态特性的问题,提出了基于无人机六自由度模型的飞行仿真动态评价方法。分析了无人机航路规划的约束条件和影响航路评价的因素,基于某型无人机六自由度飞行动力学模型和飞行控制系统模型建立了无人机飞行仿真系统模型,将航路规划与评价进行有机结合进而进行航路评价方法软件的设计,通过对无人机沿规划航路的仿真飞行参数进行动态特性分析,以更接近真实情况的仿真手段对多约束条件下的航路规划效果进行评价。结果表明,该方法形象直观的实现了对无人机规划航路的动态综合评价,满足工程需求。  相似文献   
112.
介绍了粒子群优化算法的基本思想和理论,阐述了基于粒子群优化算法的战时弹药输送路径决策分析的实现过程。通过实例应用,证实了粒子群优化算法对弹药输送路经决策问题是可行和有效的。  相似文献   
113.
Both topics of batch scheduling and of scheduling deteriorating jobs have been very popular among researchers in the last two decades. In this article, we study a model combining these two topics. We consider a classical batch scheduling model with unit‐jobs and batch‐independent setup times, and a model of step‐deterioration of processing times. The objective function is minimum flowtime. The optimal solution of the relaxed version (allowing non‐integer batch sizes) is shown to have a unique structure consisting of two consecutive decreasing arithmetic sequences of batch sizes. We also introduce a simple and efficient rounding procedure that guarantees integer batch sizes. The entire solution procedure requires an effort of O(n) (where nis the number of jobs.) © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012  相似文献   
114.
通过对维修调度问题进行分析,考虑到战斗力相关的多种目标因素,针对目前研究的目标单一,又未考虑武器的先进程度、配置等缺陷,就修复后的加权作战时间和装备尽可能少的延误数量双重目标加以研究,并给出了调度算法。从而弥补了这些缺陷,使调度更加合理。最后,算例表明模型的求解方法简单,计算时间较短,可有效地实现维修任务调度。  相似文献   
115.
This paper presents a branch‐and‐price algorithm for scheduling n jobs on m nonhomogeneous parallel machines with multiple time windows. An additional feature of the problem is that each job falls into one of ρ priority classes and may require two operations. The objective is to maximize the weighted number of jobs scheduled, where a job in a higher priority class has “infinitely” more weight or value than a job in a lower priority class. The methodology makes use of a greedy randomized adaptive search procedure (GRASP) to find feasible solutions during implicit enumeration and a two‐cycle elimination heuristic when solving the pricing subproblems. Extensive computational results are presented based on data from an application involving the use of communications relay satellites. Many 100‐job instances that were believed to be beyond the capability of exact methods, were solved within minutes. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
116.
以联合作战为例建立任务和作战平台资源模型,通过多维动态列表规划算法(Multidimensional Dynamic List Scheduling,MDLS)进行任务-平台分配,对平台选择提出了两种不同的优先权计算方法,通过对案例求解比较了不同方法的结果.  相似文献   
117.
A set of jobs can be processed without interruption by a flexible machine only if the set of tools required by all jobs can be loaded in the tool magazine. However, in practice the total number of tools required by a job set would exceed the tool magazine capacity. In such situations, the job set has to be carefully partitioned at the start of the production run such that each partition can be processed without interruption. During the production run, if there are unscheduled machine downtimes due to machine failure, this provides an additional opportunity to optimally retool the magazine for a smaller job set consisting of just the unprocessed jobs. In this paper, we study job sequencing rules that allow us to minimize the total expected cost of machine down time due to machine failures and magazine retooling, assuming a dynamic re‐sequencing of the unprocessed jobs after each machine failure. Using these rules, we develop a branch‐and‐bound heuristic that allows us to solve problems of reasonable size. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 79–97, 2001  相似文献   
118.
空天协同对地观测是对地观测领域的新趋势。为解决现有空天资源规划调度系统相对独立、协同困难的问题,分析总结了SWE(Sensor Web Enablement)标准,并在此基础上提出了空天资源对地观测协同任务规划服务模型。在此模型中,为实现观测资源共享,建立了空天观测资源传感器描述模型,能够描述典型空天资源的载荷平台、观测机理、定位信息、使用约束和工作特性等信息;为简化观测请求交互流程,基于SOA技术对SWE标准操作进行封装及简化,用户可以在不了解观测平台细节信息的情况下提交观测数据请求。为验证模型有效性,构建了空天资源对地观测协同任务规划实验平台,结果表明该模型具有较强的可实现性和适应性。  相似文献   
119.
Most scheduling problems are notoriously intractable, so the majority of algorithms for them are heuristic in nature. Priority rule‐based methods still constitute the most important class of these heuristics. Of these, in turn, parametrized biased random sampling methods have attracted particular interest, due to the fact that they outperform all other priority rule‐based methods known. Yet, even the “best” such algorithms are unable to relate to the full range of instances of a problem: Usually there will exist instances on which other algorithms do better. We maintain that asking for the one best algorithm for a problem may be asking too much. The recently proposed concept of control schemes, which refers to algorithmic schemes allowing to steer parametrized algorithms, opens up ways to refine existing algorithms in this regard and improve their effectiveness considerably. We extend this approach by integrating heuristics and case‐based reasoning (CBR), an approach that has been successfully used in artificial intelligence applications. Using the resource‐constrained project scheduling problem as a vehicle, we describe how to devise such a CBR system, systematically analyzing the effect of several criteria on algorithmic performance. Extensive computational results validate the efficacy of our approach and reveal a performance similar or close to state‐of‐the‐art heuristics. In addition, the analysis undertaken provides new insight into the behaviour of a wide class of scheduling heuristics. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 201–222, 2000  相似文献   
120.
Resource-constrained project scheduling problems with cash flows (RCPSPCF) are complex, combinatorial optimization problems. Many heuristics have been reported in the literature that produce reasonable schedules in limited project environments. However, the lack of a heuristic that dominates under differing project conditions can lead to a suboptimal choice of an appropriate heuristic for scheduling any given project. This may result in poor schedules and monetary losses. This paper reports on the application of the tabu search metaheuristic procedure for the RCPSPCF. Strategies for neighborhood generation and candidate selection that exploit the special features of the problem are combined with a simple multiheuristic start procedure. Extensive experimentation, with multiple data sets and comparison with an upper bound, indicates a significant improvement, both in project Net Present Value (NPV) as well as the number of projects, where the metaheuristic outperforms the best known heuristics in the literature. More specifically, this procedure produces the best schedules in over 85% of the projects tested, in contrast to the best single-pass heuristics which have been shown to dominate in at most 20% of the same cases. This iterative, general purpose heuristic is able to adapt significantly better to the complex interactions of the many critical parameters of the RCPSPCF than single-pass heuristics that use more specific information about each project environment. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 912–927, 1999  相似文献   
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