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521.
提出以大型试验批个数来确定身管武器生产定型时机的方法,并依据统计决策与贝叶斯分析方法,结合专家信息与收集的数据,对身管武器生产定型时机作出量化判定,为定型委员会的决策提供理论与数据支持。  相似文献   
522.
针对NSHT的运动特性和NSHT预警装备网络化趋势,对NSHT情报的分布式碎片化的特点进行了分析,设计了装备体系节点间的信息流向。在此基础上,提出了基于复杂网络理论的NSHT预警装备体系网络模型,并对网络模型的拓扑结构、统计特征等进行了研究,提出了NSHT预警装备体系连接结构的设计建议和应用思路。  相似文献   
523.
无源双基地雷达系统目标时延和多普勒频移估计,一般采用直达波通道信号与目标回波通道信号作互模糊函数处理,通过搜索互模糊函数的峰值来检测目标。虽然直达波干扰信号的互模糊函数峰值出现在零时延和零多普勒频移处,但其能量远大于目标回波信号,导致信号检测噪声门限增高,旁瓣电平增大,从而淹没目标信号。利用矢量空间的最小二乘算法抑制目标通道中的直达波信号,针对计算速度问题,提出了改进算法。仿真结果表明,该算法能够明显抑制直达波信号,同时该算法也可以完成弱目标的检测,因而具有重要的应用意义。  相似文献   
524.
Ian Bellany, an Emeritus Professor of Politics at Lancaster University, died in July 2011 at the age of 70, after a long and painful struggle with myelofibrosis, a rare and invariably terminal blood cancer. Between early 2009 and August 2010, under contract to Hurst & Co., he worked intermittently on a book about nuclear terrorism, which he provisionally entitled Before the Storm. The editor and I are grateful to Michael Dwyer at Hurst & Co. for releasing the draft. What is published here is an edited version of that draft. It may seem presumptuous to speak for Ian, but I am sure he would also have liked to thank the doctors and nurses of the NHS Morecambe Bay Universities Hospital Trust, whose skill, knowledge, and flair for improvisation kept him alive and writing for much longer than anyone expected. Alastair Bellany, Rutgers University, New Jersey, USA.
In the past, terrorists have tended to eschew acts of extreme violence for fear of alienating those whom they wish to persuade and attract to their cause. The first to discard this philosophy was the Aum group in Japan, which sought to use anthrax and acquire a nuclear weapon. Since then, attitudes have changed, spurred on by the impact on public perception of the successful Al Qaeda 9/11 attack on New York and Washington. By crossing the line between moderation and extreme violence, terrorist groups retain one valuable capability: they are much less easily deterred and have few inhibitions. This article considers the three nuclear options open to terrorists – produce a radiological contaminant bomb; build a nuclear bomb; or steal or get given a nuclear device. It examines the possibilities and probabilities of each option and considers how the implementation of the Nuclear Non-proliferation Treaty (NPT) provisions might impose some constraints on terrorists’ nuclear ambitions. By examining the doubtful nuclear security practices of different states and providing statistical evidence of an increase in levels of international terrorist violence, this article points to determined terrorists in time acquiring the means to acquire one or other variants of a nuclear weapon. It concludes that it is not a matter of “if” but “when.”  相似文献   
525.
基于舰载无人机对岸上目标的观测能力出发研究出的"理想观参",考虑各种因素对舰载无人机在任务区域飞行安全的影响,建立了地理通视性分析模型、地理可飞性分析模型、飞行可控性分析模型、弹道安全性分析模型和观参上限分析模型;综合上述模型,给出了舰载无人机可观测安全飞行空间,满足可观测安全飞行空间的观测参数即为当前环境下的"实用观参";根据本文模型研制的舰载无人机对岸射击观测辅助决策软件,实现了舰载无人机对岸射击观测的科学决策。  相似文献   
526.
针对星上路由器的路由查找功能展开研究。通过分析比较多种路由查找算法,利用软硬件协同设计的思想,给出了星上路由查找的设计与适合硬件查找的Trie树实现。给出了算法实现程序,通过实例分析了算法的优点。结果表明设计可以满足宽带卫星通信系统业务的需求。  相似文献   
527.
宋博 《国防科技》2021,42(6):5-9
美国认为太空已被普遍认定为最重要的作战域之一,未来的太空安全态势将愈发严峻。本文认为, 美国正面向未来太空对抗环境进行全面转型, 从顶层战略、作战理论、组织结构、战备训练、装备技术等方面开展研究、调整和长远布局, 如以我为主要对手谋划布局、发布系列军事航天顶层指导文件、大幅增加太空攻防作战相关经费投入等。 目前, 美军正处于新旧体系转换、 下一代能力构建发展的关键期, 不仅正在变革军队组织体制、重组太空攻防作战力量, 还积极开展系列演习演训, 以加速形成太空攻防实战能力。美军这一系列动向将对未来太空领域安全与发展产生重大影响, 应引起我高度重视。  相似文献   
528.
基于UML的航天发射指挥控制软件建模研究   总被引:1,自引:0,他引:1  
指挥控制软件是影响SLC2S高效运行的重要因素之一。为了提高航天发射指挥控制软件的综合效能,基于统一建模语言(UML)建模技术,从软件需求分析出发,对航天发射指挥控制软件开发进行了静态和动态建模,增强了软件的一致性和可复用性,为软件开发奠定了良好基础。  相似文献   
529.
ABSTRACT

Novichok agents are a class of nerve agents developed by the Soviet Union during the Cold War. In light of the use of a Novichok agent in Salisbury in March 2018, two sets of proposals to amend Schedule 1 of the 1993 Chemical Weapons Convention (CWC) have been put forth, one jointly by the United States, Canada, and the Netherlands, and the other by Russia. Both sets of proposals will be discussed and voted upon at the next Conference of States Parties of the Organisation for the Prohibition of Chemical Weapons (OPCW) in November 2019. If either set of proposals is approved, it will be the first time that the list of chemicals subject to verification under the CWC will have been modified. This viewpoint will discuss these proposals, and argue that, if adopted, the joint proposal and the portions of the Russian proposal upon which consensus can be reached would significantly strengthen the CWC by considerably expanding the coverage of its Schedule 1 and bringing Novichok agents firmly within the CWC’s verification system. We also argue that, since the OPCW Technical Secretariat did not deem the fifth group of chemicals proposed by Russia to meet the criteria for inclusion in Schedule 1, Russia should withdraw this part of its proposal from consideration. The proposals have also served an important purpose in clarifying the identity of the chemical agent used in the Salisbury incident, squarely placing it within one of the two families of Novichok agents described by the Russian chemical-weapons scientist and whistleblower Vil Mirzayanov. If either proposal is approved in November, it will be important to conduct a thorough assessment of key precursors for the synthesis of Novichok agents and assess the need to amend CWC schedules and national and multinational export-control lists accordingly.  相似文献   
530.
ABSTRACT

In 2019, the geostrategic landscape of South Asia significantly changed. A crisis between India and Pakistan involved air strikes across international boundaries for the first time since the 1971 war. Pakistan came close to economic collapse, while India re-elected hawkish Narendra Modi as prime minister in a landslide. These developments, alongside the United States’ efforts to strike a deal to leave Afghanistan and rapidly improving US-India relations, portend new challenges for Pakistan’s security managers—challenges that nuclear weapons are ill-suited to address. Despite the shifting security and political situation in the region, however, Pakistan’s nuclear posture and doctrine seem unlikely to change. This article explores the roots of Pakistan’s reliance on the traditional predictions of the nuclear revolution, most notably the notion that nuclear-armed states will not go to war with one another, and argues that this reliance on nuclear deterrence is a response both to Pakistan’s security environment and to serious constraints on moving away from nuclear weapons toward an improved conventional force posture. Pakistan’s central problems remain the same as when it first contemplated nuclear weapons: the threat from India, the absence of true allies, a weak state and a weaker economy, and few friends in the international system. While 2019 may have been a turning point for other states in the region, Pakistan is likely to stay the course.  相似文献   
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