首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   470篇
  免费   10篇
  2021年   5篇
  2019年   13篇
  2018年   9篇
  2017年   11篇
  2016年   9篇
  2015年   10篇
  2013年   78篇
  2011年   5篇
  2010年   6篇
  2009年   4篇
  2007年   6篇
  2006年   7篇
  2005年   11篇
  2004年   8篇
  2003年   5篇
  2001年   4篇
  2000年   9篇
  1999年   6篇
  1998年   5篇
  1997年   9篇
  1996年   12篇
  1995年   4篇
  1994年   10篇
  1993年   6篇
  1992年   7篇
  1991年   14篇
  1990年   8篇
  1989年   12篇
  1988年   6篇
  1987年   11篇
  1986年   9篇
  1985年   11篇
  1984年   9篇
  1983年   7篇
  1982年   6篇
  1981年   8篇
  1980年   10篇
  1979年   7篇
  1978年   8篇
  1977年   8篇
  1976年   9篇
  1975年   6篇
  1974年   11篇
  1973年   8篇
  1972年   9篇
  1971年   13篇
  1970年   3篇
  1969年   6篇
  1968年   5篇
  1967年   3篇
排序方式: 共有480条查询结果,搜索用时 31 毫秒
431.
A recent article, ‘Rage Against the Machines’, does a disservice to the debate over what explains counterinsurgency (COIN) success. While it establishes a negative correlation between the diffusion of military mechanization in the state system and COIN success, its theoretical argument does not hold up under close scrutiny and its micro-case comparison of two units in Iraq during 2003–2004 ignores obvious counter-examples and factors that influence COIN success, such as leadership. A deeper inquiry would have revealed that there is much more to COIN success than simply not having access to vehicles.  相似文献   
432.
Taking insurgency sponsorship as an instrument states have available for achieving foreign policy objectives, I consider how state-sponsors could best manipulate their support to maximize control of the proxy group. Building on research that models the state-sponsor–insurgent relationship using a principal–agent framework, I identify two key vulnerabilities to which the state-sponsor is exposed: adverse selection and agency slack. As an original contribution to the literature on state-sponsorship of insurgency, I articulate reasons why certain forms of support would be most conducive to overcoming these problems and illustrate how South Africa and Iran used those kinds of support to influence the behavior of their proxies, RENAMO and Hezbollah. Additionally, I consider how this principal–agent analysis of insurgency sponsorship also could apply when the principal is an international terrorist organization such as al Qaeda. Finally, I address the relevance of these ideas to two contemporary conflicts taking place in Syria and the Congo.  相似文献   
433.

Despite considerable post‐war planning, the British counter‐insurgency campaign in Kenya did not constitute a Colonial Office strategy for decolonisation. COIN in Kenya had one purpose: to re‐impose law and order, or British control. If for no other reason, this is demonstrated by the initial reluctance of the Colonial Office to intervene. Frequent re‐assessments and postponement of the ending of the State of Emergency, and the subordination of socio‐economic and political reforms to military objectives, show clearly that decolonisation was not high on the British list of priorities in Kenya. This article questions the relationship between COIN and decolonisation, and the validity of models of British counter‐insurgency.  相似文献   
434.
435.
进入新世纪以来,如何构建我国突发事件应急救援体系,形成灵活、高效、统一的政府应急救援联动机制,是当前急需着手解决的问题,是积极应对各种突发公共事件、保障社会和谐安全的主要对策。从突发事件应急管理现状出发,剖析了当前应急救援体系建设中存在的问题,提出了增强我国突发事件应急救援能力建设的方法,探讨了整体推进应急救援体系建设的途径。  相似文献   
436.
Passenger prescreening is a critical component of aviation security systems. This paper introduces the Multilevel Allocation Problem (MAP), which models the screening of passengers and baggage in a multilevel aviation security system. A passenger is screened by one of several classes, each of which corresponds to a set of procedures using security screening devices, where passengers are differentiated by their perceived risk levels. Each class is defined in terms of its fixed cost (the overhead costs), its marginal cost (the additional cost to screen a passenger), and its security level. The objective of MAP is to assign each passenger to a class such that the total security is maximized subject to passenger assignments and budget constraints. This paper shows that MAP is NP‐hard and introduces a Greedy heuristic that obtains approximate solutions to MAP that use no more than two classes. Examples are constructed using data extracted from the Official Airline Guide. Analysis of the examples suggests that fewer security classes for passenger screening may be more effective and that using passenger risk information can lead to more effective security screening strategies. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
437.
Accelerated degradation testing (ADT) is usually conducted under deterministic stresses such as constant‐stress, step‐stress, and cyclic‐stress. Based on ADT data, an ADT model is developed to predict reliability under normal (field) operating conditions. In engineering applications, the “standard” approach for reliability prediction assumes that the normal operating conditions are deterministic or simply uses the mean values of the stresses while ignoring their variability. Such an approach may lead to significant prediction errors. In this paper, we extend an ADT model obtained from constant‐stress ADT experiments to predict field reliability by considering the stress variations. A case study is provided to demonstrate the proposed statistical inference procedure. The accuracy of the procedure is verified by simulation using various distributions of field stresses. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.  相似文献   
438.
The bivariate negative binomial distribution of Mitchell and Paulson [17] for the case b = c = 0 is shown to be equivalent to the accident proneness model of Edwards and Gurland [4] and Subrahmaniam [19,20]. The diagonal series expansion of its joint probability function is then derived. Two other formulations of this distribution are also considered: (i) as a mixture model, which showed how it arises as the discrete analogue to the Wicksell-Kibble bivariate gamma distribution, and (ii) as a consequence of the linear birth-and-death process with immigration.  相似文献   
439.
This article generalizes the classical dichotomic reliability model to include states of partial operation. The generalized model can be considered as a special case of a general jump process. Both continuous and discrete state spaces are included. The relationship to cumulative damage shock models is discussed. Properties of the model are investigated and these are illustrated via examples. The equivalence of three forms of component independence is proved, but this equivalence does not generalize to the property of zero covariance. Alternative forms of series and parallel connections and the effect of component replacement are discussed.  相似文献   
440.
The historical and, to some extent, the current role of attribute inspection sampling in the United States Air Force is described. Some insight into consideration culminating in revisions made to the original MIL-STD-105 sampling plans is provided. These revisions were motivated from a practitioner's perspective rather than that of a statistical expert. Some significant administrative applications within the Air Force are described, and a practical method, based on the total amount of inspection, is given for distinguishing between sampling plans that have a fixed risk level (i.e., common value on the OC curves).  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号