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   656篇
  免费   63篇
  国内免费   43篇
  2024年   1篇
  2023年   3篇
  2022年   4篇
  2021年   14篇
  2020年   8篇
  2019年   30篇
  2018年   33篇
  2017年   38篇
  2016年   39篇
  2015年   24篇
  2014年   69篇
  2013年   113篇
  2012年   22篇
  2011年   45篇
  2010年   44篇
  2009年   45篇
  2008年   50篇
  2007年   36篇
  2006年   28篇
  2005年   30篇
  2004年   23篇
  2003年   19篇
  2002年   9篇
  2001年   5篇
  2000年   8篇
  1999年   4篇
  1998年   3篇
  1997年   3篇
  1995年   5篇
  1994年   3篇
  1993年   3篇
  1990年   1篇
排序方式: 共有762条查询结果,搜索用时 15 毫秒
621.
高中地理案例教学是适应新课程改革的需要而尝试的一种教学方法,本文简要阐述了地理案例教学的特点、作用,并着重阐述了在编写地理案例、问题设计以及在案例教学实施中需要注意的一些问题。  相似文献   
622.
教师的水平制约着教育的发展,双语教师在双语教育中起着重要作用。本文对新疆喀什地区泽普县维族双语教师的汉语水平进行实地调研,找出他们汉语水平存在的问题,并针对问题提出建议。  相似文献   
623.
零故障情况下指数型数据环境因子计算方法   总被引:1,自引:0,他引:1  
目前,常用的指数型数据环境因子计算公式缺乏广泛的适用性,当被试系统故障数为零时,公式不可用.针对这一问题,曾有过工程上的探讨,但其处理方法不尽合理.在此基础上进行了进一步的改进,在增强了因子计算公式适用性的同时,使其结果更具合理性.  相似文献   
624.
讨论了导航装备数字维修平台的网络传输安全性问题,分析其安全需求,提出采用Java安全技术来解决堆修平台的安全性.从工程项目实际需要的角度出发,阐述了在导航装备数字维修平台中的Java安全机制以及实现技术.  相似文献   
625.
随着全球导航卫星系统的广泛应用,其安全性问题也逐渐成为人们关注的焦点。为了对目前最具隐蔽性的诱导式欺骗技术进行检测,提出一种对两路导航信号同时进行处理的combo-signal模型,并提出基于这种信号处理模型来对诱导式欺骗信号进行检测的方法;分析了该方法的检测门限;采用北斗的B1I 和B1C信号在实现了combo-signal处理模型的软件接收机上对该检测方法进行了验证,实验结果证明该方法可以有效地对诱导式欺骗进行检测,统计得到的检测概率跟前面的分析结果一致。  相似文献   
626.
Alex Neads 《战略研究杂志》2019,42(3-4):425-447
Military capacity building (MCB) is as problematic as it is ubiquitous, with the British experience in Sierra Leone providing a rare example of ostensible success. This article critiques the dominant conceptualisation of MCB as purely a principal–agent (PA) problem, using military change scholarship to examine the impact of wartime British intervention on the Sierra Leonean armed forces. Here, indigenous military change was both externally driven and fundamentally adaptive in nature, allowing MCB to bypass some of the difficulties predicted by PA models. However, this adaptive approach nonetheless failed to reconcile Western military values with prevailing Sierra Leonean culture, complicating post-war stabilisation efforts.  相似文献   
627.
Most countries put significant amounts of time and effort in writing and issuing high-level policy documents. These are supposed to guide subsequent national defence efforts. But do they? And how do countries even try to ensure that they do? This paper reports on a benchmarking effort of how a few “best of breed” small- to medium-sized defence organisations (Australia, Canada, and New Zealand) deal with these issues. We find that most countries fail to link goals to resources and pay limited attention to specific and rigorous ex-ante or post-hoc evaluation, even when compared to their own national government-wide provisions. We do, however, observe a (modest) trend towards putting more specific goals and metrics in these documents that can be – and in a few rare cases were – tracked. The paper identifies 42 concrete policy “nuggets” – both “do’s and don’ts” – that should be of interest to most defence policy planning/analysis communities. It ends with two recommendations that are in line with recent broader (non-defence) scholarship on the policy formulation-policy implementation gap: to put more rigorous emphasis on implementation (especially on achieving desired policy effects), but to do so increasingly in more experiential (“design”) ways, rather than in industrial-age bureaucratic ones (“PPBS”-systems).  相似文献   
628.
Given the advances made in conventional weapon capabilities, precision should by now be the accepted and expected norm in cyberspace as well. In this article I argue that developing precision cyber weapon systems, to be used during a lawful conflict, can be an important part of a responsible national security strategy to reduce the amount of violence and physical destruction in conflicts. I first describe a precision cyber weapon system in a military context. I then present three compelling rationales for the development of precision cyber weapon systems based on ethical, operational, and financial considerations. To support the position, I address several arguments that have been levied against their development. Thereafter I present several recommendations for a way ahead.  相似文献   
629.
This article discusses roles and missions of the United States Navy with a particular focus on the Baltic Sea. That particular sea has gained renewed political and military attention following Russia's resurgent and increasingly hybrid-offensive foreign policy. Baltic nations, uncertain of what the future holds, ought to look at sea power and maritime missions in the Baltic, as well as US naval presence in Europe, to draw lessons for future posture.  相似文献   
630.
The rise of private military and security companies (PMSCs) challenges our notion of military professionals. PMSCs bring new claims to professional status and legitimacy outside military institutions and represent an increasing diffusion of - and competition over - military and security expertise. In light of this development, understanding the formation of professional identities in military and private security organisations is as an important undertaking. This paper contributes to this endeavour by analysing professional self-images in the Swedish Armed Forces and how these relate to PMSCs. The study is based on data collected from official documents, semi-structured interviews and a small-scale survey among senior military officers. Focusing on military understandings of PMSCs and contractors, the analysis provides much-needed insight into relational aspects of professional identity formation outside the US context. Furthermore, it points to discrepancies in organisational and group levels in understandings of commercial security actors, and paves the way for future research.  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