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801.
Validation of a strategy for harbor defense based on the use of a min‐max algorithm receding horizon control law 下载免费PDF全文
We present a validation of a centralized feedback control law for robotic or partially robotic water craft whose task is to defend a harbor from an intruding fleet of water craft. Our work was motivated by the need to provide harbor defenses against hostile, possibly suicidal intruders, preferably using unmanned craft to limit potential casualties. Our feedback control law is a sample‐data receding horizon control law, which requires the solution of a complex max‐min problem at the start of each sample time. In developing this control law, we had to deal with three challenges. The first was to develop a max‐min problem that captures realistically the nature of the defense‐intrusion game. The second was to ensure the solution of this max‐min problem can be accomplished in a small fraction of the sample time that would be needed to control a possibly fast moving craft. The third, to which this article is dedicated, was to validate the effectiveness of our control law first through computer simulations pitting a computer against a computer or a computer against a human, then through the use of model hovercraft in a laboratory, and finally on the Chesapeake Bay, using Yard Patrol boats. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 247–259, 2016 相似文献
802.
Tai Ming Cheung 《战略研究杂志》2016,39(5-6):728-761
ABSTRACTChina’s defense science, technology, and industrial system has been undergoing a far-reaching transformation over the past two decades and the single biggest factor behind this turnaround is the role of external technology and knowledge transfers and the defense industry’s improving ability to absorb these inputs and convert into localized output. China is pursuing an intensive campaign to obtain defense and dual-use civil–military foreign technology transfers using a wide variety of means, which is explored in this article. 相似文献
803.
“Evergreening” is a strategy wherein an innovative pharmaceutical firm introduces an upgrade of its current product when the patent on this product expires. The upgrade is introduced with a new patent and is designed to counter competition from generic manufacturers that seek to imitate the firm's existing product. However, this process is fraught with uncertainty because the upgrade is subject to stringent guidelines and faces approval risk. Thus, an incumbent firm has to make an upfront production capacity investment without clarity on whether the upgrade will reach the market. This uncertainty may also affect the capacity investment of a competing manufacturer who introduces a generic version of the incumbent's existing product but whose market demand depends on the success or failure of the upgrade. We analyze a game where capacity investment occurs before uncertainty resolution and firms compete on prices thereafter. Capacity considerations that arise due to demand uncertainty introduce new factors into the evergreening decision. Equilibrium analysis reveals that the upgrade's estimated approval probability needs to exceed a threshold for the incumbent to invest in evergreening. This threshold for evergreening increases as the intensity of competition in the generic market increases. If evergreening is optimal, the incumbent's capacity investment is either decreasing or nonmonotonic with respect to low end market competition depending on whether the level of product improvement in the upgrade is low or high. If the entrant faces a capacity constraint, then the probability threshold for evergreening is higher than the case where the entrant is not capacity constrained. Finally, by incorporating the risk‐return trade‐off that the incumbent faces in terms of the level of product improvement versus the upgrade success probability, we can characterize policy for a regulator. We show that the introduction of capacity considerations may maximize market coverage and/or social surplus at incremental levels of product improvement in the upgrade. This is contrary to the prevalent view of regulators who seek to curtail evergreening involving incremental product improvement. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 71–89, 2016 相似文献
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805.
量子技术是基于量子力学和其他学科交叉产生的新兴学科,已经涉及到计算、信息、导航、能源等多个应用领域。近年来,随着量子技术的快速发展和应用潜力,量子技术已成为研究热点并逐步走向应用。与此同时,世界新军事革命发展中武器装备须具有远程精确化、职能化、隐身化、无人化的技术特点。结合量子技术的特点,从量子计算,量子通信与量子密码、量子控制、量子导航、量子雷达,量子电池,量子技术对作战模式的改变等方面对武器装备领域的应用、作战能力和作战模式进行阐述。研究表明,量子计算的发展必然使现有武器装备的性能得到提高、作战能力得到提升,进而改变现有作战模式。 相似文献
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807.
This article argues that since the advent of democracy, the South African Police Service (SAPS) has been plagued by poor administration. Having inherited a repressive police force, the post-apartheid national police commissioners (NPCs) have found it difficult to transform the organisation. Among the unintended consequences has been a rise in police deaths. Although police deaths can be attributed to numerous factors, this article focuses on fault lines in the SAPS administration through a strengths, weaknesses, opportunities and threats (SWOT) analysis drawing largely on existing scholarly debates. Essential theoretical perspectives have been employed to gain insight into the root causes of the problem. The article concludes that poor administration and a lack of trust, partnership and collaboration between police officers and community members have perpetuated the killing of police officers. These killings are further compounded by the flawed and ill-conceived selection and appointment of NPCs. As a consequence, the article recommends that the appointment of NPCs should be promptly reviewed. It further recommends that each potential candidate should have risen through the ranks and must fully comprehend the challenges facing the organisation. 相似文献
808.
Tamir Libel 《Defence Studies》2016,16(2):137-156
The paper’s main argument is that Israel’s security policy, which traditionally focused on defending its territorial integrity against regular Arab armed forces, was, by the 2010s, transformed into one that focuses on facing a variety of state- and non-state-based threats. Neo-realist explanations could neither account for the contested nature of the security debate during this period, nor the inconsistent evolution of the policy. The present study aims to solve this conundrum by introducing an alternative approach known as 4th generation strategic culture research. The paper is comprised of four parts. First, the origins and evolution of strategic culture are reviewed, with emphasis placed on the commonly accepted weaknesses that, to date, have prevented it from being used as a testable theoretical concept, and subsequently as an explanatory factor for security policy changes. The second part presents the “modernist constructivism” approach that bridges the gap between traditional constructivism and hypothesis-driven research design. Next, the paper introduces the emerging fourth generation in strategic culture literature, followed by a conceptual framework designed to resolve the inherent weaknesses of the more traditional approaches. Finally, this conceptual framework is applied to analyse the transformation of Israel’s security policy between 1982 and 2014. 相似文献
809.
Mikkel Vedby Rasmussen 《Defence Studies》2016,16(4):374-389
Taking its point of departure in Donald Rumsfeld’s second term as US Secretary of Defense (2001–2006), this article analyses the crisis of strategic leadership in Western national security. Three “traps” are identified that explain why Donald Rumsfeld ultimately was a failure as defence secretary and demonstrate the perils of national security governance. These traps are termed the inquisitor trap, the strong leader trap and the delegation trap. It is argued that our understanding of strategic leadership in national security, particularly in defence, can benefit from insights gained from the study of strategic leadership in business. As such, this article engages the recent trend of merging insights from business and military strategy. 相似文献
810.
通过分析空袭兵器、空袭历史、防空体系和防护技术的发展,将空袭模式划分为防区内(低空)地毯式打击、防区内(中低空)多手段打击、防区外陆海空三位一体精确打击三代。将防护体系划分为"边陲墙壕烽火台+腹地城池"、"防空系统+防护工程"两代。并预测了第四代空袭模式:防区外陆海空天四位一体全球快速精确打击和与之相对应的第三代"防空反导+信息化防护工程"防护体系。根据打击力和防护力相生相克的矛盾运动,提出了末端防护工程应吸收信息技术、发展综合防护技术,信息化时代的防护工程不仅要保护可以转入地下的目标,而且要保护无法转入地下的目标。从源头上为陆基目标防护的研究和建设提供参考和启迪。 相似文献