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521.
This article assesses the prospects for a strategy of incrementalism to lead to achievement of the core bargain of the Treaty on the Non-Proliferation of Nuclear Weapons: non-nuclear weapon states' nuclear nonproliferation in exchange for nuclear weapon states' nuclear disarmament to the point of “global zero.” Game theory, prospect theory, and liberal international theory are used to evaluate the potential of a strategy of incrementalism. While separately each has insights to offer, it is when all three theoretical approaches are used in tandem that meaningful explanatory gains emerge. The article concludes that incrementalism probably cannot lead to complete nonproliferation and global nuclear zero. Instead, signal events (as described by prospect theory) are needed to “punctuate” incremental processes in negotiations (best explained by liberal international theory) in order to move past hindrances such as international structural constraints (exemplified by game theory) and the conservative risk-taking propensities of state elites (described by prospect theory).  相似文献   
522.
Boko Haram terrorism has been recognized by Nigerian President Jonathan as the most threatening and complex security issue in Nigeria since independence. In response, the Federal Government of Nigeria has committed itself to different counterterrorism measures, which are largely dominated by “hard politics” and military mobilization. Spending heavily on defense to upgrade military hardware and train personnel in a counterterrorism role, Nigeria has also boosted its strategic importance in the “Global War on Terror”. However, this attempt has become unpopular as it has failed to contain Boko Haram within a short time frame and has made insufficient headway against unabated terror, with human rights costs among the host communities and amidst a surge of stakeholders' discordance. As a matter of concern, this article seeks to assess Boko Haram as an opponent in Nigeria's war on terror (WOT) and to ascertain the challenges the country faces, the alternative measures open to it, and possible ways forward.  相似文献   
523.
The rejection of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) by the U.S. Senate in October 1999 could have been avoided, and the consequences of that vote still loom in the minds of supporters of the treaty. President Barack Obama has embraced the vision of a world free of nuclear weapons, and a key element of the Obama administration's arms control agenda is delivering on U.S. CTBT ratification. In order to secure the two-thirds majority in the Senate necessary to ratify the treaty, senators that remain skeptical of nuclear disarmament must also be convinced that the entry into force of the CTBT is in the national security interest of the United States. This article provides an analysis of the issues surrounding U.S. CTBT ratification divided into three segments—verifiability of the treaty, reliability of the U.S. stockpile, and the treaty's impact on U.S. national security—and concludes that CTBT ratification serves the security objectives of the United States. The CTBT constitutes an integral component of the multilateral nonproliferation architecture designed to prevent the proliferation of nuclear weapons, and it constrains the qualitative development of nuclear weapons, thereby hindering efforts by states of concern to develop advanced nuclear weapons.  相似文献   
524.
雷达组网是实现反隐身的一种有效技术。通过模拟隐身飞机在有无干扰情况下从空中和低空突防,对海上编队雷达网的对抗过程进行仿真,经过认知模型对探测效能的解算,得出优化的舰艇部署阵位。仿真结果表明所建立模型的可行性和正确性,并可为舰艇指挥员综合决策提供科学依据。  相似文献   
525.
基于作战协同航母编队兵力配置方法   总被引:1,自引:0,他引:1  
从作战协同的角度研究航母编队兵力配置问题。首先介绍了航母编队兵力配置空间协同方法,即层次协同、海域协同、空域协同、方向协同、高度协同等方法。根据基于航母编队对空作战、对海作战、对岸作战和对潜作战4种基本作战样式下,探讨了协同因素对兵力配置的影响与约束,并提出了相应的原则与思路,进一步完善航母编队兵力配置理论。  相似文献   
526.
针对双舰编队协同制导作战条件下如何对空袭目标进行排序这一问题,依据作战时间给出了排序算法。首先对平台的作战时间进行分析和求解,将射击周期分成了2段,把静态拦截排序问题转化为了2台处理机的同顺序作业排序问题,然后根据输入信息的改变而不断调整空袭目标的顺序以解决动态拦截排序问题,最后在想定条件下仿真计算,结果表明该算法具有较好的适用性。  相似文献   
527.
平流层飞艇飞行模态分析   总被引:1,自引:0,他引:1       下载免费PDF全文
平流层飞艇的总体布局、升空原理和工作模式明显不同于导弹、飞机等传统飞行器,其动力学特性亦不同于上述飞行器,须深入研究其飞行动力学的基本特性、一般规律和内在机理。针对此问题,系统研究了平流层飞艇的飞行模态。采用小扰动方法推导了平流层飞艇的线性运动方程,将其解耦分组为纵向运动方程和横侧向运动方程;定义模态及模态参数,研究平流层飞艇的模态分析方法;通过计算分析状态方程的特征值和特征向量,研究了平流层飞艇的飞行模态。结果表明:纵向运动由浮沉、浪涌和摆动三种模态叠加而成,横侧向运动由偏航衰减、侧滑衰减和滚转振荡三种模态叠加而成。  相似文献   
528.
针对超高速SpaceFibre星载网络中多源数据传输的确定性和实时性应用需求,提出一种分类细粒度低延时确定性调度算法。该算法基于差异化调度策略的思想,将数据流划分为三类。为实现网络资源的细粒度分配,引入扩展时隙。该算法采用无冲突均匀调度方法,降低了数据包的平均排队延时。为适应有效载荷组网的航天应用场景,该算法兼顾网络拓扑结构生成调度方案。为验证算法有效性,在OPNET仿真平台下利用自定义建模技术搭建网络仿真模型。仿真结果表明:相比优先权调度和无冲突连续调度机制,该算法实现了时间敏感数据流的确定性传输;随着时隙数目的增加,网络的延时性能和抗抖动性能显著提升,吞吐量性能得到保证;该算法具有一定的航天工程实用价值。  相似文献   
529.
We investigate the problem of scheduling a fleet of vehicles to visit the customers located on a path to minimize some regular function of the visiting times of the customers. For the single‐vehicle problem, we prove that it is pseudopolynomially solvable for any minsum objective and polynomially solvable for any minmax objective. Also, we establish the NP‐hardness of minimizing the weighted number of tardy customers and the total weighted tardiness, and present polynomial algorithms for their special cases with a common due date. For the multivehicle problem involving n customers, we show that an optimal solution can be found by solving or O(n) single‐vehicle problems. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 61: 34–43, 2014  相似文献   
530.
Here, we revisit the bounded batch scheduling problem with nonidentical job sizes on single and parallel identical machines, with the objective of minimizing the makespan. For the single machine case, we present an algorithm which calls an online algorithm (chosen arbitrarily) for the one‐dimensional bin‐packing problem as a sub‐procedure, and prove that its worst‐case ratio is the same as the absolute performance ratio of . Hence, there exists an algorithm with worst‐case ratio , which is better than any known upper bound on this problem. For the parallel machines case, we prove that there does not exist any polynomial‐time algorithm with worst‐case ratio smaller than 2 unless P = NP, even if all jobs have unit processing time. Then we present an algorithm with worst‐case ratio arbitrarily close to 2. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 351–358, 2014  相似文献   
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