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511.
ABSTRACT

The strategic culture approach has been suffering from a prolonged theoretical stalemate, despite a surge in case studies, which culminated in the Johnston-Gray debate and subsequent schism. The present paper outlines a new approach designed to overcome this deadlock, and consists of three arguments. First, the three previous generations of strategic culture studies have failed to explain how strategic culture influences behaviour. Second, aligning strategic culture theory-building with discursive institutionalism offers a way to overcome this fundamental fallacy. Third, a research programme for strategic culture should draw on computational social science to enable it to present and test middle-range theories.  相似文献   
512.
大型船舶空气尾流场对海上飞机安全降落有重要的影响,因此对其进行有效防治技术研究在保障飞机安全、大型船舶海上活动等方面有重要意义。采用计算流体力学方法开展大型船舶空气尾流场特性及其防治技术的数值模拟研究,以带有Spalart-Allmaras湍流模型的Reynolds平均Navier-Stokes方程构建模拟平台开展数值模拟,得到大型船舶空气尾流场规律特性。在此基础上,提出主动补气防治新技术,分别阐述其理论基础、核心方法和技术方案;根据主动补气防治技术思想和理论,进一步开展数值模拟验证研究。结果表明,该技术能显著改善空气尾流场的流场品质,使流场趋于平稳均匀,减小对飞机海上降落的影响。该技术进一步完善了可实现工程应用,并保证飞机海上降落安全,有巨大的应用潜力。  相似文献   
513.
Military transformation is a complex, slow, asymmetric, changeable, political, and not necessarily completely rational process that clearly needs an effective monitoring mechanism. This paper fills a gap in current literature by creating and testing a model for multi-dimensional and multi-level quantitative monitoring of military transformation applicable in any country. The model is based on 10 transformation indicators that reflect changes in organizational structure, personnel structure, weapon systems, and defense spending. Its application on a sample of seven countries (USA, United Kingdom, France, Netherlands, Poland, Russia, and China) in the period from 1992 to 2010 unexpectedly shows that the USA – a protagonist in the transformation process among allies as well as globally – has carried out the smallest relative change. The non-directed transformation index indicates that Russia carried out 51.8% more change (or 34.1 index units), and the directed index indicates that Poland carried out 157.2% (or 40.8 index units) more change than the USA.  相似文献   
514.
NDIS技术在网络监测中的实现   总被引:1,自引:0,他引:1  
阐述了利用NDIS进行网络包的监测和分析的基本原理,在此基础上实现了对网络适配器在数据链路层网络包的监测,并通过数据报文结构的分析,再现了应用层协议的实现过程.  相似文献   
515.
由于无线传感器网络在能量消耗、内存开销和计算能力等方面的局限性,传统的网络密钥管理方法已不适用。为此提出了一种适用于无线传感器网络的密钥预分配方法——基于(t,n)-门限方案,给出了密钥分配方法,并从方案的连通性、安全性等方面进行了有效的分析,结果表明该算法在这些方面有一定的优势。  相似文献   
516.
针对模糊识别算法中,样本特征向量中各参量(分量)对状态分类的贡献权重难以确定的问题,提出了利用随机森林算法对特征参量的重要度评估结果作为特征权重的方法。通过对柴油机台架试验振动信号的跟踪分析,获得了柴油机在磨合期、100摩托小时、200摩托小时、300摩托小时及400摩托小时5种不同使用期(典型状态)的75个振动信号样本,然后计算出各类样本在幅域、时域和频域的特征参量,利用随机森林算法进行特征选择,确定4个重要特征参量及其权重,用统计方法得出其隶属度函数,最后根据评价向量对样本进行识别,识别准确率达到94%以上。  相似文献   
517.
Parts of NATO’s contemporary planning framework called the comprehensive operations planning directive (COPD), and parts of the operation-level planning process should be revised since they suffer from methodological inconsistency. This claim is defended by discussing contradicting methodological properties and heuristics applied when framing and managing a military problem in accordance with the COPD. The methodological inconsistency within the COPD; in other words, simultaneously applying contradictory methodological properties, implies one theoretical and three practical implications. The theoretical implication is summarised in a meta-theoretical framework and explained by discussing five methodological properties: non-linearity, emergence, independently changeable generalisations, invariance and boundaries. The three practical implications of methodology imply that methodology is guiding: the problem-frame, conceptual development and action. To improve military planners’ understanding and management of these four identified implications, NATO is recommended to develop a “handbook of methodology.” The purpose of such a handbook should be to emphasise the utility of methodology when planning military operations.  相似文献   
518.
浅议高校科研经费的管理与监督   总被引:1,自引:0,他引:1  
针对高校科研经费成为高校资金重要来源和科研经费管理的现状,笔者就科研经费管理与监督工作现存问题、科研经费管理和科研经费监督工作问题对策进行了初步的探讨。  相似文献   
519.
随着网络技术、多媒体技术的发展,网络教学已经成为一种重要的教学形式,如何正确把握网络教学的模式,抓住特点,准确定位教师在网络教学中的角色,上好每一堂课,应该是每一位老师考虑的问题。  相似文献   
520.
The signature of a system with independent and identically distributed (i.i.d.) component lifetimes is a vector whose ith element is the probability that the ith component failure is fatal to the system. System signatures have been found to be quite useful tools in the study and comparison of engineered systems. In this article, the theory of system signatures is extended to versions of signatures applicable in dynamic reliability settings. It is shown that, when a working used system is inspected at time t and it is noted that precisely k failures have occurred, the vector s [0,1]nk whose jth element is the probability that the (k + j)th component failure is fatal to the system, for j = 1,2,2026;,nk, is a distribution‐free measure of the design of the residual system. Next, known representation and preservation theorems for system signatures are generalized to dynamic versions. Two additional applications of dynamic signatures are studied in detail. The well‐known “new better than used” (NBU) property of aging systems is extended to a uniform (UNBU) version, which compares systems when new and when used, conditional on the known number of failures. Sufficient conditions are given for a system to have the UNBU property. The application of dynamic signatures to the engineering practice of “burn‐in” is also treated. Specifically, we consider the comparison of new systems with working used systems burned‐in to a given ordered component failure time. In a reliability economics framework, we illustrate how one might compare a new system to one successfully burned‐in to the kth component failure, and we identify circumstances in which burn‐in is inferior (or is superior) to the fielding of a new system. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009  相似文献   
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