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101.
基于遗传算法的目标分配问题研究   总被引:13,自引:2,他引:11  
通过对地空导弹部队射击指挥中目标分配问题的分析,建立了目标优化分配数学模型。在此基础上,给合遗传算法对模型进行求解。通过在具体实例中的应用表明,采用遗传算法为有效地解决这一复杂组合优化问题提供了一种新途径。  相似文献   
102.
数字水印是数字作品版权保护的重要技术手段。与噪声污染类似,数字水印的嵌入必然会损失原作品的质量。数字图像的质量直接关系其商业价值,在给定降质约束下自适应地调节嵌入深度是符合产业化标准的数字水印关键技术之一。根据DCT交流系数的拉普拉斯分布模型,推导了DCT域典型水印算法中拉伸系数与信噪比和峰值信噪比之间的理论关系。依据该理论关系,得到了在给定降质约束下一类典型图像水印算法的拉伸系数估计方法,实验结果表明该估计方法具有较高的精度。  相似文献   
103.
对地面防空战斗部署方案进行评估是防空作战中非常关键的一环,防空战斗部署主要包括防空兵器战斗部署和情报预警雷达组网部署两部分。首先分析了地面防空兵器战斗部署的评估指标体系,用数学规划的方法对其作战能力进行评估。然后运用开马尔可夫排队网络对情报预警雷达组网部署的空情预警能力进行评估。  相似文献   
104.
105.
多火力单元责任扇区的动态调整是防空导弹指挥控制系统的核心功能之一,通过引入可打击目标数和覆盖目标数的概念及计算方法,提出了一种新的多火力单元责任扇区调整方法。该方法能快速有效地确定多火力单元责任扇区调整方案。  相似文献   
106.
Central to the mainstream Sikh identity is the concept of ethically-justified force, used as a last resort. There is no place for absolute pacifism in this conception of ethical living. Fighters and martyrs occupy an important place in the Khalsa narrative, and Sikhs are constantly reminded of the sacrifices and heroism of their co-religionists of the past. This article explores how the Sikh warrior identity is manifested in the contemporary world. It examines the Sikhs who, in the 1980s and 1990s, were involved on both sides of the Punjab crisis: those militants who fought for a Sikh homeland (“Khalistan”) and those Sikhs in the Indian army who suppressed the insurgency. The article also looks beyond the militants and soldiers to Sikhs employed in modern security-related professions, the broader issue of Sikh symbols relating to the use of force, and violence within the Sikh diaspora. An examination of the Sikhs in various parts of the world reveals additional uses and consequences of ideology, whether in enlistment in the armed forces of the states in which they live, or in the support of the militancy in India, particularly in the 1980s. The conclusion is that the modern Sikh warrior is a nuanced actor behaving in various ways, some overt and some subtle: the warrior is willing to physically fight those perceived to be tyrannous, but most initiatives have shifted to pursuing justice through non-violent means, such as legal struggles for civil rights. Although armed Sikh militancy against the Indian government is in the past, there are strong residual resentments still requiring redress. All of this is of great relevance to understanding the ethics of armed force within modern Sikhism.  相似文献   
107.
强军目标是新时期军队建设的行动纲领。思想政治建设必须围绕强军目标展开。军队思想政治工作受所处环境的影响和制约。贯彻强军目标创设良好的思想政治工作环境,首先要从本单位自身做起,建设净化优美的军营“小环境”,塑造军营环境的“奋斗之关”“陶冶之美”“形象之美”,增强思想政治工作环境的推动力、感染力和约束力。  相似文献   
108.
随着舰艇编队网络中心作战模式的产生与发展,其队形配置问题必须重新给予考虑。首先介绍了网络化反导作战系统的远程数据作战能力;其后,从指挥通信、火力掩护和一次耦合杀伤区3个方面给出舰舰间距的约束条件,以远程数据作战条件下编队舰空导弹杀伤区增量最大为优化目标,建立编队舰舰间距优化模型,并在此基础上结合电子干扰的要求,给出了编队队列角的最优范围解算方法;最后,在一定的战场假设下,通过示例的方式对模型的有效性与适应性进行了验证。  相似文献   
109.
We consider the problem of assessing the value of demand sharing in a multistage supply chain in which the retailer observes stationary autoregressive moving average demand with Gaussian white noise (shocks). Similar to previous research, we assume each supply chain player constructs its best linear forecast of the leadtime demand and uses it to determine the order quantity via a periodic review myopic order‐up‐to policy. We demonstrate how a typical supply chain player can determine the extent of its available information in the presence of demand sharing by studying the properties of the moving average polynomials of adjacent supply chain players. The retailer's demand is driven by the random shocks appearing in the autoregressive moving average representation for its demand. Under the assumptions we will make in this article, to the retailer, knowing the shock information is equivalent to knowing the demand process (assuming that the model parameters are also known). Thus (in the event of sharing) the retailer's demand sequence and shock sequence would contain the same information to the retailer's supplier. We will show that, once we consider the dynamics of demand propagation further up the chain, it may be that a player's demand and shock sequences will contain different levels of information for an upstream player. Hence, we study how a player can determine its available information under demand sharing, and use this information to forecast leadtime demand. We characterize the value of demand sharing for a typical supply chain player. Furthermore, we show conditions under which (i) it is equivalent to no sharing, (ii) it is equivalent to full information shock sharing, and (iii) it is intermediate in value to the two previously described arrangements. Although it follows from existing literature that demand sharing is equivalent to full information shock sharing between a retailer and supplier, we demonstrate and characterize when this result does not generalize to upstream supply chain players. We then show that demand propagates through a supply chain where any player may share nothing, its demand, or its full information shocks (FIS) with an adjacent upstream player as quasi‐ARMA in—quasi‐ARMA out. We also provide a convenient form for the propagation of demand in a supply chain that will lend itself to future research applications. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 515–531, 2014  相似文献   
110.
Military commanders, policymakers, and analysts have recently embraced the concept of combined action as a powerful tool to improve the effectiveness of Afghan security forces in the fight against the Taliban. In doing so, they explicitly draw inspiration from the Combined Action Program employed by US Marines during the Vietnam War. This program is widely considered to have greatly improved the effectiveness of South Vietnamese government forces and contributed to increased population security in its area of operations and is considered a model worthy of emulation. This study finds that the success of the Vietnam-era Combined Action Program was more qualified than contemporary proponents argue. It argues that successes were tempered, and conditioned, by the choice of junior commanders, the level of operational control enjoyed by the US Marines, and the way the local forces were recruited and deployed. These conditions offer valuable lessons for those seeking to employ combined action not only in present-day Afghanistan, but also in future counterinsurgency campaigns.  相似文献   
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