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631.
A new technique for solving large‐scale allocation problems with partially observable states and constrained action and observation resources is introduced. The technique uses a master linear program (LP) to determine allocations among a set of control policies, and uses partially observable Markov decision processes (POMDPs) to determine improving policies using dual prices from the master LP. An application is made to a military problem where aircraft attack targets in a sequence of stages, with information acquired in one stage being used to plan attacks in the next. © 2000 John Wiley & Sons, Inc., Naval Research Logistics 47: 607–619, 2000  相似文献   
632.
决策信息传输能力的大小,直接决定着防空作战行动的作战效能,进而决定了防空作战的成败。针对防空群决策信息传输问题,用Petri网建模,从时效性和可靠性两个方面,对防空群的决策信息传输能力进行了分析,得到了不同指挥方式下的信息传输能力的度量。对防空群通信能力的分析和指挥体制的优化有一定的借鉴和指导意义。  相似文献   
633.
基于多属性目标决策的威胁评估排序模型   总被引:2,自引:0,他引:2  
针对当前海战中对舰艇编队构成威胁的空中目标的特点,运用目标多属性理论探索对空中目标的威胁排序问题.提出了一种对空中目标进行威胁评估和排序的方法,并通过示例介绍了威胁评估和排序的求解过程.该方法有效地解决了目标威胁评估与排序问题,提高了舰艇编队防空作战能力.  相似文献   
634.
Gamma accelerated degradation tests (ADT) are widely used to assess timely lifetime information of highly reliable products with degradation paths that follow a gamma process. In the existing literature, there is interest in addressing the problem of deciding how to conduct an efficient, ADT that includes determinations of higher stress‐testing levels and their corresponding sample‐size allocations. The existing results mainly focused on the case of a single accelerating variable. However, this may not be practical when the quality characteristics of the product have slow degradation rates. To overcome this difficulty, we propose an analytical approach to address this decision‐making problem using the case of two accelerating variables. Specifically, based on the criterion of minimizing the asymptotic variance of the estimated q quantile of lifetime distribution of the product, we analytically show that the optimal stress levels and sample‐size allocations can be simultaneously obtained via a general equivalence theorem. In addition, we use a practical example to illustrate the proposed procedure.  相似文献   
635.
We consider the problem of optimally maintaining a stochastically degrading, single‐unit system using heterogeneous spares of varying quality. The system's failures are unannounced; therefore, it is inspected periodically to determine its status (functioning or failed). The system continues in operation until it is either preventively or correctively maintained. The available maintenance options include perfect repair, which restores the system to an as‐good‐as‐new condition, and replacement with a randomly selected unit from the supply of heterogeneous spares. The objective is to minimize the total expected discounted maintenance costs over an infinite time horizon. We formulate the problem using a mixed observability Markov decision process (MOMDP) model in which the system's age is observable but its quality must be inferred. We show, under suitable conditions, the monotonicity of the optimal value function in the belief about the system quality and establish conditions under which finite preventive maintenance thresholds exist. A detailed computational study reveals that the optimal policy encourages exploration when the system's quality is uncertain; the policy is more exploitive when the quality is highly certain. The study also demonstrates that substantial cost savings are achieved by utilizing our MOMDP‐based method as compared to more naïve methods of accounting for heterogeneous spares.  相似文献   
636.
We study an (R, s, S) inventory control policy with stochastic demand, lost sales, zero lead‐time and a target service level to be satisfied. The system is modeled as a discrete time Markov chain for which we present a novel approach to derive exact closed‐form solutions for the limiting distribution of the on‐hand inventory level at the end of a review period, given the reorder level (s) and order‐up‐to level (S). We then establish a relationship between the limiting distributions for adjacent values of the reorder point that is used in an efficient recursive algorithm to determine the optimal parameter values of the (R, s, S) replenishment policy. The algorithm is easy to implement and entails less effort than solving the steady‐state equations for the corresponding Markov model. Point‐of‐use hospital inventory systems share the essential characteristics of the inventory system we model, and a case study using real data from such a system shows that with our approach, optimal policies with significant savings in inventory management effort are easily obtained for a large family of items.  相似文献   
637.
This article provides conditions under which total‐cost and average‐cost Markov decision processes (MDPs) can be reduced to discounted ones. Results are given for transient total‐cost MDPs with transition rates whose values may be greater than one, as well as for average‐cost MDPs with transition probabilities satisfying the condition that there is a state such that the expected time to reach it is uniformly bounded for all initial states and stationary policies. In particular, these reductions imply sufficient conditions for the validity of optimality equations and the existence of stationary optimal policies for MDPs with undiscounted total cost and average‐cost criteria. When the state and action sets are finite, these reductions lead to linear programming formulations and complexity estimates for MDPs under the aforementioned criteria.© 2017 Wiley Periodicals, Inc. Naval Research Logistics 66:38–56, 2019  相似文献   
638.
针对信息作战指挥决策中大数据的运用问题,通过对大数据的海量信息检索能力、交叉复现的分析能力、“全信息”运算能力、智能决策执行能力的研究,提出了大数据为其提供按需订制的情报信息、多元多维的决策视角、动态实时的决策支持、智能自主的决策方式的观点,初步探索了大数据在信息作战指挥决策中的运用,对将大数据引入信息作战指挥决策具有十分重要的指导意义。  相似文献   
639.
为了科学合理地对装备保障方案进行权衡分析和优化筛选,从装备保障方案综合评价的具体需求出发,提出了装备保障方案综合评价系统的总体结构,基于 OU(组织单元)与 BOU(基本组织单元)的组织建模法构建了装备保障方案综合评价的组织结构模型,设计了系统的角色和各功能模块,并给出系统运作的一般流程和具体事例,验证了该系统的可行性和有效性。  相似文献   
640.
复杂系统性质决定了复杂系统管理的特殊性,而兵棋推演可以为复杂系统管理提供更加符合其特性的决策辅助支持。讨论了复杂系统的性质及其影响,研究了兵棋推演用于复杂系统管理的原因和方法,并结合战争兵棋推演,介绍了兵棋工程建设中系统研发、推演组织和工程管理方面的创新与实践问题。最后,给出了未来发展的趋势。  相似文献   
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