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51.
In the face of rapid technological change and the creation of ambitious military modernisation programmes, this paper argues that land forces, in managing the relationship between force levels and the adoption of military robotics, must recognise that there are inherent limits to techno-centric force reduction efforts and realise the inefficacy of substituting skilled soldiers with robots. It begins with an overview of how the proper integration of robotics into a military’s force structure can improve capability, save lives and potentially reduce costs, but suggests that common accounts of robot utility are exaggerated and endanger the risk assessment processes governing the adoption of said technologies and relevant personnel settings. The paper explores the limits of robotic solutions to military problems, discussing their technical limitations, redundancy and related issues that, when combined with a technico-moral skills degradation problem also detailed within, point to the need to reshape force structures to suit the adoption of robotics while preserving existing levels of human staffing.  相似文献   
52.
This article reviews innovation processes in defence. It analyses the way and the context under which these processes are carried out. The article covers the features of defence goods with impact on innovation, the development of a new good, the institutional arrangements that support these processes and the effect of innovation on industrial market. The analysis helps to identify the causes of facts observed in practice, such as poor performance in terms of product quality, cost or delivery time, as well as to assess potential remedies. Some policy implications, which can be derived from this analysis, are finally outlined.  相似文献   
53.
We consider the problem of assessing the value of demand sharing in a multistage supply chain in which the retailer observes stationary autoregressive moving average demand with Gaussian white noise (shocks). Similar to previous research, we assume each supply chain player constructs its best linear forecast of the leadtime demand and uses it to determine the order quantity via a periodic review myopic order‐up‐to policy. We demonstrate how a typical supply chain player can determine the extent of its available information in the presence of demand sharing by studying the properties of the moving average polynomials of adjacent supply chain players. The retailer's demand is driven by the random shocks appearing in the autoregressive moving average representation for its demand. Under the assumptions we will make in this article, to the retailer, knowing the shock information is equivalent to knowing the demand process (assuming that the model parameters are also known). Thus (in the event of sharing) the retailer's demand sequence and shock sequence would contain the same information to the retailer's supplier. We will show that, once we consider the dynamics of demand propagation further up the chain, it may be that a player's demand and shock sequences will contain different levels of information for an upstream player. Hence, we study how a player can determine its available information under demand sharing, and use this information to forecast leadtime demand. We characterize the value of demand sharing for a typical supply chain player. Furthermore, we show conditions under which (i) it is equivalent to no sharing, (ii) it is equivalent to full information shock sharing, and (iii) it is intermediate in value to the two previously described arrangements. Although it follows from existing literature that demand sharing is equivalent to full information shock sharing between a retailer and supplier, we demonstrate and characterize when this result does not generalize to upstream supply chain players. We then show that demand propagates through a supply chain where any player may share nothing, its demand, or its full information shocks (FIS) with an adjacent upstream player as quasi‐ARMA in—quasi‐ARMA out. We also provide a convenient form for the propagation of demand in a supply chain that will lend itself to future research applications. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 515–531, 2014  相似文献   
54.
Abstract

The creation of the Africa Command (AFRICOM) has reflected the growth in the strategic importance of Africa in US foreign policy since the end of the 1990s. One of the objectives of this new geographical military command is to forge closer links between foreign, security and development policies. However, this approach met with a number of difficulties associated with the challenge of ‘inter-agency cooperation’ among rather disparate actors from foreign affairs, defence and development. In addition, the establishment of AFRICOM has met with fierce criticism in the US and elsewhere – especially in Africa – culminating in the charge that the US foreign and development policies in Africa are being militarised. Although AFRICOM has a number of interesting features, this paper shows that it has reacted to these criticisms by realigning itself more closely with the traditional model of a military command, at the expense of the innovative interagency elements.  相似文献   
55.
ABSTRACT

What do we mean by nuclear proliferation? What does it mean to proliferate? This article investigates both the literal and figurative meaning of the term “proliferation.” It argues that many of the definitions and conceptualizations of nuclear proliferation often used by scholars are either limited in their utility or logically inconsistent. It then reconceptualizes and redefines the term, incorporating an understanding of both its etymological origins and the geopolitical context in which the phenomenon occurs. It concludes by exploring the potential impact that the politicization of the phenomenon may have on the identification of occurrences of proliferation, from both an academic and a policy-making perspective.  相似文献   
56.
The stochastic sequential assignment problem (SSAP) considers how to allocate available distinct workers to sequentially arriving tasks with stochastic parameters such that the expected total reward obtained from the sequential assignments is maximized. Implementing the optimal assignment policy for the SSAP involves calculating a new set of breakpoints upon the arrival of each task (i.e., for every time period), which is impractical for large‐scale problems. This article studies two problems that are concerned with obtaining stationary policies, which achieve the optimal expected reward per task as the number of tasks approaches infinity. The first problem considers independent and identically distributed (IID) tasks with a known distribution function, whereas in the second problem tasks are derived from r different unobservable distributions governed by an ergodic Markov chain. The convergence rate of the expected reward per task to the optimal value is also obtained for both problems. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
57.
将武器装备系统的组成部分分为3类,通过分析得出适合装备系统的特定m维修策略,能够在保证装备较高使用可用度的同时,最大程度地缩减维修保障成本.利用更新过程某些特性,建立特定m维修策略下的使用可用度模型,简化了使用可用度的计算.  相似文献   
58.
针对某小型武器稳定系统稳定精度差的问题,构建了其控制系统的数学模型,通过仿真施加试验台架扰动信号,对现系统采用的传统PID控制器进行仿真计算,得到其动态稳定精度,并把得到的和定型试验稳定精度数据对应的外扰模拟信号作为改造后系统的标准扰动输入,对线性自抗扰控制器进行了比对仿真研究.仿真结果表明,系统采用线性自抗扰控制器具有响应速度快、稳定精度高、抗扰能力强的优点.这一方法得到的仿真结果和实车具有较高一致性,可以有效解决实车参数调试困难的问题.  相似文献   
59.
目前 ,在以会计准则为企业会计政策规范主体的模式下 ,企业对会计政策有较大的选择空间 ,不同的会计政策选择 ,产生企业不同结果的会计信息 ,对企业利害关系集团产生不同的利益分配结果和社会资源配置效率。本文通过分析企业会计政策选择的起因 ,探讨了会计政策选择的正确定位 ,对于企业正确选择会计政策、维护资本市场的健康运行具有一定的借鉴意义  相似文献   
60.
欧盟具有相对成熟的太空技术,处于国际太空力量发展的第一梯队,其太空安全政策是在基于维护太空自主权的前提下,寻求太空与安全防务政策的统一,从而实现共同外交和安全政策的整体目标,目前已取得了较大进展。本文认为,从未来发展来看,面对有限的太空资源优势和脆弱的太空环境,欧盟将会继续利用其技术优势和集体力量,努力保障其太空关键基础设施安全和太空自主权,同时进一步将太空安全重点向军事竞争领域聚焦,将其作为拓展战场空间维度的重要途径。  相似文献   
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