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661.
软件测试工具很难达到通用的目标,大多数该类工具都是具体针对某一种或几种程序语言的.对于目前我军常用的程序编写语言开发相应的软件自动测试工具是十分必要的.介绍了一个面向C程序的测试用例自动生成系统,重点阐述了其系统结构的构成以及所采用的一个新的搜索寻优算法.该算法有效地改善了前有算法的一些缺陷,显示出不错的效果.  相似文献   
662.
云模型及其在指挥控制系统可靠性分析中的应用   总被引:7,自引:0,他引:7  
根据指挥控制系统的特点及作战应用的具体情况,从指挥控制系统的可靠性出发,提出了适合指控系统可靠性分析的云模型。通过拟定性能评价指标,导出各指标的云模型及其多维加权综合云的重心,应用云重心评价方法进行分析;并通过案例,运用基于PC-L INM AP的云重心评价方法,以影响指挥控制系统可靠性的两个重要性能指标为依据,分析了未来联合作战中指挥控制系统的可靠性,比较贴近作战实际,可信度较高。  相似文献   
663.
随着防空C3I系统的发展,防空作战决策的过程较以往更为自动化,用于生成各种作战辅助决策方案的计算机模型也具备随着作战环境改变所表现出一定的自适应调整的特征.影响防空作战决策结果正确性的因素众多,表现这些因素的信息有些是冲突的,为得到更为准确、有效的决策方案,各类冲突信息的处理成为防空作战的核心问题.构造了一种在冲突信息环境下基于对策理论的融合模型,以对策理论的相关算法实现了融合中心各类信息的交互决策.实践表明,这一融合模型能有效地解决防空作战决策中各类信息的综合处理问题,具有一定的实用价值.  相似文献   
664.
地地战役战术导弹火力运用中,对导弹打击目标的选取是导弹部队制定合理科学作战方案所面临的现实问题。针对给定弹量和特定作战意图对打击目标进行优化选择问题,运用0-1型整数规划,建立合理的数学模型并确定最优打击目标。通过应用实例表明,此方法简便易行,可操作性较强,具有一定的实用价值。  相似文献   
665.
This paper studies a periodic‐review pricing and inventory control problem for a retailer, which faces stochastic price‐sensitive demand, under quite general modeling assumptions. Any unsatisfied demand is lost, and any leftover inventory at the end of the finite selling horizon has a salvage value. The cost component for the retailer includes holding, shortage, and both variable and fixed ordering costs. The retailer's objective is to maximize its discounted expected profit over the selling horizon by dynamically deciding on the optimal pricing and replenishment policy for each period. We show that, under a mild assumption on the additive demand function, at the beginning of each period an (s,S) policy is optimal for replenishment, and the value of the optimal price depends on the inventory level after the replenishment decision has been done. Our numerical study also suggests that for a sufficiently long selling horizon, the optimal policy is almost stationary. Furthermore, the fixed ordering cost (K) plays a significant role in our modeling framework. Specifically, any increase in K results in lower s and higher S. On the other hand, the profit impact of dynamically changing the retail price, contrasted with a single fixed price throughout the selling horizon, also increases with K. We demonstrate that using the optimal policy values from a model with backordering of unmet demands as approximations in our model might result in significant profit penalty. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
666.
采用混合分层理论和Ressiner混合变分原理,在壳的厚度方向取二次插值函数来描述位移沿厚度方向的变化规律;采用三次和四次插值函数来描述横向应力沿厚度方向的变化,线形处理筋条的变形,推导出粘弹加筋层合圆柱壳的动力学方程和协调方程组,并采用拉普拉斯变换,得出简支粘弹加筋层合圆柱壳稳态振动的响应解。对于自由阻尼层合圆柱壳,所给出的振动频率和结构损耗因子与解析解吻合良好.结果表明,较高的层间横向正应力是引起潜艇消声瓦脱落的主要因素,而采用较高模量的粘弹性阻尼材料将降低层间横向应力的幅值.  相似文献   
667.
In rewards-based crowdfunding, entrepreneurs solicit donations from a large number of individual contributors. If total donations exceed a prespecified funding target, the entrepreneur distributes nonmonetary rewards to contributors; otherwise, their donations are refunded. We study how to design such campaigns when contributors choose not just whether to contribute, but also when to contribute. We show that strategic contribution behavior—when contributors intentionally delay until campaign success is likely—can arise from the combination of nonrefundable (potentially very small) hassle costs and the risk of campaign failure, and can explain pledging patterns commonly observed in crowdfunding. Furthermore, such delays do not hurt the entrepreneur if contributors are perfectly rational, but they do if contributors are distracted, that is, if they might fail to return to the campaign after an intentional delay. To mitigate this, we find that an entrepreneur can use a simple menu of rewards with a fixed number of units sold at a low price, and an unlimited number sold at a higher price; this segments contributors over time based on the information they observe upon arrival. We show that, despite its simplicity, such a menu performs well compared to a theoretically optimal menu consisting of an infinite number of different rewards and price levels under many conditions.  相似文献   
668.
拟带宽 Toeplitz 系统的秩 1 修正算法   总被引:2,自引:0,他引:2       下载免费PDF全文
本文以带宽Toeplitz系统的快速并行解法为基础,通过建立秩1的修正格式讨论了拟带宽Toeplitz系统的一种快速并行算法,其串行运算量为9nh+O(h).设p为处理机台数,当p≤n时,并行运算量为 ;当p=3n时,运算量为2h ̄2log2n+O(1),其中h表示拟带宽宽度。  相似文献   
669.
Possession of a brand is a sine qua non for economic success, not least because it connotes trust in delivering the value promised. Although Western arms exporters offer branded systems whose sales are influenced by price, there is a plethora of other economic variables, such as offset requirements and life-cycle support. Entrants to the international arms market will struggle without such arms “packages.” China’s entry, however, goes beyond the traditional economic paradigm. A four-stage historical model offers the backdrop for identifying the drivers that have forged its market entry into 55 countries worldwide. The strategy initially focused on sales of rudimentary military equipment for political purposes, but recently it has begun to commercialize exports, repositioning them from a low- to a high-tech sales trajectory. A Sino “brand” is thus emerging, reflecting both competitiveness and diplomatic considerations, especially non-interference in client state domestic affairs.  相似文献   
670.
Mark Erbel 《Defence Studies》2017,17(2):135-155
This article reappraises the two most-studied country cases of military outsourcing: the USA and the UK. It argues that the contemporary wave of military contracting stretches back to the beginning of the cold war and not only to the demobilisation of armies in the 1990s or the neoliberal reforms introduced since the 1980s. It traces the political, technological and ideational developments that laid the groundwork for these reforms and practices since the early cold war and account for its endurance today. Importantly, it argues that a persistent gap between strategic objectives and resources, i.e. the challenge to reconcile ends and means, is an underlying driver of military contracting in both countries. Contemporary contracting is thus most closely tied to military support functions in support of wider foreign and defence political objectives. Security services in either state may not have been outsourced so swiftly, if at all, without decades of experience in outsourcing military logistics functions and the resultant vehicles, processes and familiarities with public-private partnerships. The article thus provides a wider and deeper understanding of the drivers of contractualisation, thereby improving our understanding of both its historical trajectory and the determinants of its present and potential futures.  相似文献   
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