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861.
In this article, we study a class of Quasi‐Skipfree (QSF) processes where the transition rate submatrices in the skipfree direction have a column times row structure. Under homogeneity and irreducibility assumptions we show that the stationary distributions of these processes have a product form as a function of the level. For an application, we will discuss the ‐queue that can be modeled as a QSF process on a two‐dimensional state space. In addition, we study the properties of the stationary distribution and derive monotonicity of the mean number of the customers in the queue, their mean sojourn time and the variance as a function of for fixed mean arrival rate. © 2016 Wiley Periodicals, Inc. Naval Research Logisticsxs 66:57–72, 2019 相似文献
862.
Kenneth M. Swope 《Small Wars & Insurgencies》2019,30(4-5):937-967
ABSTRACT This paper examines the career of one of the most notable of Chinese state officials in the mid-nineteenth century, General Zuo Zongtang (1812–1885) at a time when the Qing Empire was beset by enemies on all sides along with the massive Taiping Rebellion (1851–65). The paper explores how Zuo created a coherent and flexible counter-insurgency doctrine that underpinned his suppression of the Taipings, the Nian, Muslim rebels of the northwest and the defeat of a massive Sufi revolt in Central Asia. The paper also shows how Zuo helped convince the Russians to return territory they occupied in Central Asia, thereby preserving the territorial integrity of the Qing Empire in the region. 相似文献
863.
M. A. Thomas 《Defence Studies》2019,19(2):149-169
In the mid-2000s, the United States Army was embroiled in counterinsurgency missions in Iraq and Afghanistan that required deeper understanding of local social systems. The Army turned to systems thinking and design thinking to model and understand the world, define problems, and develop approaches to strategic and operational challenges. However, the Army’s approach as expressed in publications and doctrine encourages the development of complicated, unsupported, and unfalsifiable hypotheses. The risk is that the Army will act on incorrect assumptions and develop plans that are fragile. 相似文献
864.
Christopher M. Faulkner 《Civil Wars》2019,21(1):83-103
Do Private Military and Security Companies (PMSCs) impact peace duration after civil war? I argue that the role these organisations play in a conflict can impact post-conflict stability. Specifically, I suggest that variance in services provided by PMSCs can influence rebels’ calculations about relative capabilities. These calculations then contribute to the probability for civil war recurrence. Building on the bargaining framework, with a focus on information and commitment problems, this article demonstrates that PMSCs participating in armed combat operations can jeopardise the stability of peace following civil war. Three case narratives (Angola, Sierra Leone and Croatia) are used to probe the theoretical argument and results are illustrative – PMSCs serving as force multipliers contribute to an increase in the probability for conflict recurrence. 相似文献
865.
Matthijs M. Maas 《Contemporary Security Policy》2019,40(3):285-311
Many observers anticipate “arms races” between states seeking to deploy artificial intelligence (AI) in diverse military applications, some of which raise concerns on ethical and legal grounds, or from the perspective of strategic stability or accident risk. How viable are arms control regimes for military AI? This article draws a parallel with the experience in controlling nuclear weapons, to examine the opportunities and pitfalls of efforts to prevent, channel, or contain the militarization of AI. It applies three analytical lenses to argue that (1) norm institutionalization can counter or slow proliferation; (2) organized “epistemic communities” of experts can effectively catalyze arms control; (3) many military AI applications will remain susceptible to “normal accidents,” such that assurances of “meaningful human control” are largely inadequate. I conclude that while there are key differences, understanding these lessons remains essential to those seeking to pursue or study the next chapter in global arms control. 相似文献
866.
Joakim Erma Møller 《Defence Studies》2019,19(3):235-256
Norway, Sweden and Finland have proclaimed a willingness to cooperate militarily in a future crisis or conflict despite their diverging alliance affiliation. This article assesses their ability to do so through various elements affecting their interoperability, with Arctic Challenge, a multinational military exercise, as an empirical basis. The analysis finds that the NATO/non-NATO-divide has a negative impact on the trilateral defence cooperation, especially on exchange of information and aspects related to command and control. At the same time, Finland and Sweden have become largely NATO-standardized through their active partnership with the Alliance. This has affected interoperability aspects, such as communication, culture, and the compatibility of technical solutions, in a positive manner. Through agreements with the Alliance, as well as domestic legal changes, the two NATO-partners have facilitated receiving military assistance from Norway and other NATO-members during a crisis. Other agreements between the Nordic countries, however, have been limited to peacetime. 相似文献
867.
Kathryn M. Schumacher Richard Li‐Yang Chen Amy E.M. Cohn Jeremy Castaing 《海军后勤学研究》2016,63(3):236-246
We consider the problem of determining the capacity to assign to each arc in a given network, subject to uncertainty in the supply and/or demand of each node. This design problem underlies many real‐world applications, such as the design of power transmission and telecommunications networks. We first consider the case where a set of supply/demand scenarios are provided, and we must determine the minimum‐cost set of arc capacities such that a feasible flow exists for each scenario. We briefly review existing theoretical approaches to solving this problem and explore implementation strategies to reduce run times. With this as a foundation, our primary focus is on a chance‐constrained version of the problem in which α% of the scenarios must be feasible under the chosen capacity, where α is a user‐defined parameter and the specific scenarios to be satisfied are not predetermined. We describe an algorithm which utilizes a separation routine for identifying violated cut‐sets which can solve the problem to optimality, and we present computational results. We also present a novel greedy algorithm, our primary contribution, which can be used to solve for a high quality heuristic solution. We present computational analysis to evaluate the performance of our proposed approaches. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 236–246, 2016 相似文献
868.
The debate over whether there exists a British counter-insurgency tradition of minimum force is one that has been thoroughly discussed. Is there anything left to say? This study suggests there is further insight to be attained if one explicitly evaluates the concept of minimum force in relation to the conduct of the security forces in the years of the Northern Ireland conflict. Through an examination of three key periods in the conflict, it will be shown that while there was invariably an awareness of the need to act with restraint among senior officers at the strategic level, this was often difficult to apply at the tactical level in the heat of confrontation. The argument demonstrates that the British Army, and other instruments of the state, rarely acted in a manner that could be described as ‘minimal’. Instead, it was the broader liberal values of the British state that explains largely the degrees of restraint exhibited by the government and security forces. 相似文献
869.
Recent literature on whether military spending affects economic growth argues that the relationship may be a conditional one. We add to this literature by considering the role that ‘good institutions’ play in the effect of military spending on growth. Using data from a sample of over 100 countries from 1988 to 2010, our analysis suggests that the effect of military spending on growth is generally negative or zero at best, and this effect is mitigated in the presence of good economic and political institutions. 相似文献
870.
This study examines whether the exclusion of ethnic groups from political power is an important contributing factor to domestic terrorism. To empirically test this question, we employ a negative binomial regression estimation on 130 countries during the period from 1981 to 2005. We find that countries in which certain ethnic populations are excluded from political power are significantly more likely to experience domestic terrorist attacks and to suffer from terrorist casualties; furthermore, ethnic group political exclusion is a more consistent and substantive predictor of domestic terrorist activity than general political repression or economic discrimination. 相似文献