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121.
“太空安全战略”专题编者按 组稿专家:杨乐平(国防科技大学空天科学学院教授、博士生导师) 近年来,以美国重建太空司令部与天军独立为标志,国际太空领域战略竞争与军事对抗日益加剧,太空前所未有地应用于军事与安全,太空安全也受到了前所未有的挑战。为了解未来太空安全发展和主要国家太空安全战略动向,深化太空安全战略研究,《国防科技》编辑部于2021年6月启动“太空安全战略”专题征文活动,国内相关学者积极投稿,经专家遴选,本期发表入选稿件6篇。来稿内容涵盖未来30年太空安全发展预测、美国太空安全最新发展、俄罗斯太空安全政策、欧盟太空安全政策、日本太空安全战略以及印度太空力量发展等主题,较为全面地反映了当前国际太空安全领域的最新发展与战略动向。从长远看,随着地球以外人类活动的增加、太空新经济蓬勃发展和太空创造财富规模不断扩大,水平大幅提升,太空将超越陆、海、空成为国家安全最重要的领域。从这个意义上讲,太空安全战略研究学术价值与影响较大,值得高度关注。  相似文献   
122.
Cyber operations are relatively a new phenomenon of the last two decades.During that period,they have increased in number,complexity,and agility,while their design and development have been processes well kept under secrecy.As a consequence,limited data(sets)regarding these incidents are available.Although various academic and practitioner public communities addressed some of the key points and dilemmas that surround cyber operations(such as attack,target identification and selection,and collateral damage),still methodologies and models are needed in order to plan,execute,and assess them in a responsibly and legally compliant way.Based on these facts,it is the aim of this article to propose a model that i))estimates and classifies the effects of cyber operations,and ii)assesses proportionality in order to support targeting decisions in cyber operations.In order to do that,a multi-layered fuzzy model was designed and implemented by analysing real and virtual realistic cyber operations combined with interviews and focus groups with technical-military experts.The proposed model was evaluated on two cyber operations use cases in a focus group with four technical-military experts.Both the design and the results of the evaluation are revealed in this article.  相似文献   
123.
基于MSP430单片机的海浪水压场自动测量系统   总被引:1,自引:1,他引:0  
提出了基于MSP430单片机的水压场自动测量系统的设计方案和实现方法并进行了实际测量.解决了自动测量系统中的低噪声、低功耗、高分辨率、大容量存储等关键技术.实验结果表明:该系统具有自动运行、电池供电、记录时间长等特点.适于高海况条件下的海浪水压场的测量.  相似文献   
124.
用有限时间热力学的方法分析具有热阻、热漏、内不可逆性的定常流联合卡诺型热机循环.导出了在傅立叶导热定律下联合循环功率、效率和生态学指标的性能,并进行优化;得到功率、效率和生态学指标之间的优化关系,并由数值计算分析了功率、效率和循环熵产率之间的关系.所得的结果表明,最大生态学指标下的效率十分接近于联合循环可以达到的最大效率;相应的熵产率也要低于以输出功率为优化目标时的熵产率.  相似文献   
125.
Ron Rosenbaum, How the End Begins: The Road to a Nuclear World War III. Simon & Schuster, 2011. 305 pages, $28.  相似文献   
126.
This article applies the concept of nuclear ambivalence to the case of the Islamic Republic of Iran. Nuclear ambivalence differs from other approaches to understanding nuclear proliferation in that it focuses on the deeply misunderstood relationship between the two potential uses of nuclear power: energy and weapons. According to this theory, the civilian applications of nuclear technology cannot be separated from the potential military applications and vice versa. Ambivalence, therefore, extends into the realm of states’ nuclear intentions, making it impossible to know with certainty what a potential proliferator's “true” intentions are. This article will demonstrate that the concept of nuclear ambivalence applies in the case of Iran, suggesting that current international nonproliferation efforts run the risk of encouraging rather than discouraging Iranian weaponization. The final section outlines recommendations for policy makers to reverse this counterproductive nonproliferation approach.  相似文献   
127.
The policies toward countries aspiring to acquire nuclear weapons continue to be heavily contested, differing even among countries that consider nuclear proliferation as one of the main threats to international security. This article maps the actual policies of liberal democracies toward Iran and North Korea along a continuum from confrontation to accommodation. Using data from an expert survey, the authors outline four main findings. First, policies toward both Iran and North Korea have become increasingly confrontational over time. Second, no policy convergence was observed among the states studied; that is, notwithstanding the adoption of joint sanctions, differences remained between states preferring confrontation and those opting for accommodation. Third, states maintained remarkably stable policy profiles over time. Finally, despite obvious differences between the norm violations of North Korea and Iran, states generally followed remarkably similar policies toward both countries. The authors’ findings indicate that states exhibit stable preferences for either confrontation or accommodation toward nuclear aspirants. Although a comprehensive examination of the causes of these policy differences is beyond the scope of this article, the authors present evidence that a major cleavage exists between members and non-members of the Non-Aligned Movement, indicating that the degree to which nuclear aspirants’ sovereignty should be respected is a main issue of contention.  相似文献   
128.
In his 2009 Prague speech and the 2010 Nuclear Posture Review, President Barack Obama committed the United States to take concrete steps toward nuclear disarmament while maintaining a safe, secure, and effective nuclear deterrent. There is an inherent tension between these two goals that is best addressed through improved integration of nuclear weapons objectives with nuclear arms control objectives. This article reviews historical examples of the interaction between the two sets of objectives, develops a framework for analyzing opportunities for future integration, and suggests specific ideas that could benefit the nuclear weapons enterprise as it undergoes transformation and that could make the future enterprise compatible with a variety of arms control futures.  相似文献   
129.
Radioactive sealed sources have a long history and a much wider worldwide distribution than do weapons-usable fissile materials. This article compares the mechanisms for controlling radioactive sources with those of weapons-usable materials and makes the case for improved policy making on the safe and secure management of radioactive sources (often referred to simply as “sources”). Such sources have been widely distributed with commercial and government support to nearly every country, yet there are no legally binding, international agreements or regulations to control any aspect of their life cycle. This is problematic because some sources that are disused, abandoned, or otherwise fall out of regulatory control could be used in the form of a radiological dispersal device (RDD, or dirty bomb). An RDD could pose significant economic and psychological impacts with the potential for detrimental effects on public health. The lack of international measures to control sources is troubling for several reasons: creating an RDD is much easier than fashioning a nuclear weapon from scratch or from stolen fissile materials; given the many incidents involving diversion from regulatory control and the misuse of sources, an RDD attack would be one of the more likely scenarios; materials security for sources is generally weak and inconsistent; it is nearly impossible to determine the total amount of sources manufactured and distributed; used sources are frequently found uncontrolled and transiting borders, and penalties are light at best; the market-based supply and demand of sources facilitates their rapid and loosely regulated distribution; and the “peaceful uses” aspect of the Treaty on the Non-Proliferation of Nuclear Weapons along with norms that began developing around the time of Atoms for Peace have promoted the nearly unchecked global distribution of sources. Several immediate and long-term actions are suggested to reduce the threat posed by radiological sources.  相似文献   
130.
Between the 1960s and the 1990s, the US chemical industry went from lobbying against the Geneva Protocol and promoting increased funding for chemical warfare to refusing to produce binary chemical weapons and assisting with the negotiations of the Chemical Weapons Convention (CWC)—even though the treaty included provisions that could be costly to industry. What happened in those thirty years to make the US chemical industry reverse its position on chemical weapons? This article argues these changes were largely caused by the chemical industry's desire to reform the negative public image it had acquired due to its involvement in the Agent Orange scandal and other high-profile incidents during the 1970s and 1980s. The chemical industry's assistance with CWC negotiations may be explained after an examination of the US public policy literature, which argues that industry will support apparently costly regulations if doing so helps it repair a damaged public image and ensures greater profits in the long run.  相似文献   
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