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221.
Forecasting Nuclear Proliferation in the 21st Century: The Role of Theory (vol. 1, 312 pages, $24.95) and A Comparative Perspective (vol. 2, 488 pages, $24.95), edited by William C. Potter with Gaukhar Mukhatzhanova. Stanford University Press, 2010.  相似文献   
222.
Concerns about climate change and energy security have prompted some countries to revive dormant nuclear fission power programs to meet growing energy demands and reduce carbon dioxide emissions. However, this so-called nuclear renaissance based on fission would have major drawbacks in the areas of safety, security, and nonproliferation. Nuclear fusion, however, is portrayed by its proponents as mitigating these drawbacks, and scientists continue to pursue fusion's promise with two large-scale projects: the International Thermonuclear Experimental Reactor (ITER), and the Laser Inertial Fusion Engine (LIFE) reactor. Although supporters often hail fusion as proliferation resistant, the technology could be used to create weapons-usable fissile material. This article explains how fissile material could be created in ITER or LIFE and analyzes other nonproliferation implications of fusion; the authors discuss the various challenges faced by ITER and LIFE.  相似文献   
223.
The contemporary history of three countries was marked on July 1974 when the Greek colonels overthrew the legitimate government of Cyprus, Turkey invaded the island to preserve her interests and Greece returned to democracy, but withdrew from NATO. The apathy of her allies was a bitter experience for Greece, considering that the government in Athens was struggling to cope with the consequences of the invasion and Turkey's aggression, as well as with the diplomatic isolation caused by the seven-year dictatorial rule. This paper examines the response of the Greek government and makes particular reference to Karamanlis's archives and Greek parliamentary proceedings. The purpose of the present study is to explore whether Greece was genuinely committed to the settlement of the Cyprus issue and failed due to lack of support or simply ignored the appeals of the Cypriot people and pursued more vital foreign policy objectives, thus contributing to the partition of the island.  相似文献   
224.
In 1955, the New Zealand government authorised the creation of a Special Forces unit to operate with British forces in Malaya to counter a communist-inspired guerrilla insurgency. Drawing upon the operational experiences of the New Zealand SAS largely taken from the Cold War period, and underpinned by Colin Gray's Special Forces essentials of ‘economy of force’ and ‘expansion of choice’, this article will show how New Zealand's SAS is now accepted not only as a respected and relevant part of the nation's military capability, but also empowers its political decision-makers with the confidence to take on significant, and at times difficult, strategic foreign-policy choices.  相似文献   
225.
This article investigates the cognitive limitations on policy change in counterinsurgency (COIN) efforts by examining why American decision-makers failed to revise their government strategy substantially while fighting the insurgency in Afghanistan in 2003–2014 and why their British counterparts were more successful in adjusting their policies in the Malayan insurgency in 1948–1954. Unlike most of the COIN literature that concentrates on military strategy and tactics, the analysis of government policy-making in Malaya holds some important political lessons for American leaders today despite differences between the insurgencies in Afghanistan and British Malaya. As a response to the criticism of COIN studies in general that they lack theoretical guidance, this article utilizes an integrated cognitivist-prospect theory framework. It is argued that some of the COIN literature mistakenly suggests that a more difficult strategic situation was primarily responsible for American failure in Afghanistan. Instead, American decision-makers faced a more difficult task cognitively than their British counterparts, as policy change in Afghanistan would have required greater ideational change. American principals were much more attached to their beliefs emotionally, had no alternative problem representation, and had to shift between frames in order to engineer a response that was more in line with events on the ground in Afghanistan. Regarding prospect theory, findings indicate that gains frames appear to be unhelpful in monitoring progress until catastrophic failure endangers the reference point, and that decision-makers often have more than one reference point to attune their policies to, which often results in suboptimal choices with regard to at least one reference point.  相似文献   
226.
基于排队论的装备维修人员数量需求模型*   总被引:3,自引:0,他引:3  
确定维修人员需求是对装备维修机构进行科学管理和对维修人员进行有计划培训的需要。在分析装备维修人员构成的随机服务系统特征的基础上,运用排队论理论建立了以平均等待时间为目标的维修人员需求的愿望模型,该模型可更加确切地描述各专业对维修人员的实际需求。通过对模型进行仿真,结果表明了模型的合理性。  相似文献   
227.
刘晓才  安强 《国防科技》2014,35(5):19-21
卓越指挥人才培养是院校人才培养新的增长点。文章着眼卓越指挥人才的实战化训练,分析了军事教学训练体系的构成模块,提出了教学训练的内容拓展,并从教学条件建设、师资队伍交流和养成机制等方面提出了保障要求。  相似文献   
228.
For most firms, especially the small‐ and medium‐sized ones, the operational decisions are affected by their internal capital and ability to obtain external capital. However, the majority of the literature on dynamic inventory control ignores the firm's financial status and financing issues. An important question that arises is: what are the optimal inventory and financing policies for firms with limited internal capital and limited access to external capital? In this article, we study a dynamic inventory control problem where a capital‐constrained firm periodically purchases a product from a supplier and sells it to a market with random demands. In each period, the firm can use its own capital and/or borrow a short‐term loan to purchase the product, with the interest rate being nondecreasing in the loan size. The objective is to maximize the firm's expected terminal wealth at the end of the planning horizon. We show that the optimal inventory policy in each period is an equity‐level‐dependent base‐stock policy, where the equity level is the sum of the firm's capital level and the value of its on‐hand inventory evaluated at the purchasing cost; and the structure of the optimal policy can be characterized by four intervals of the equity level. Our results shed light on the dynamic inventory control for firms with limited capital and short‐term financing capabilities.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 184–201, 2014  相似文献   
229.
We investigate and compare the impact of the tax reduction policies implemented in the United States and China to stimulate consumer purchase of new automobiles and improve manufacturers' profits. The U.S. policy provides each qualifying consumer with a federal income tax deduction on state and local sales and excise taxes paid on the purchase price (up to a cutoff level), whereas the Chinese policy reduces the vehicle sales tax rate for consumers. We observe that these policy designs are consistent with the tax management system and the economic environment in the respective country. We analytically determine the effects of the two tax reduction policies on the automobile sales and the manufacturer's and the retailer's profits. Numerical examples are then used to provide insights on the importance of certain factors that influence the effects of the two policies. Finally, a numerical experiment with sensitivity analysis based on real data is conducted to compare the merits and characteristics of the two policies under comparable conditions. We find that the U.S. policy is better than the Chinese policy in stimulating the sales of high‐end automobiles, whereas the Chinese policy is better than the U.S. policy in improving the sales of low‐end automobiles. The U.S. policy is slightly more effective in increasing the profitability of the automobile supply chain; but, in general, the Chinese policy is more cost effective. The methodology developed herein can be used to evaluate other tax reduction policies such as those related to the purchase of energy‐saving vehicles and to serve as a decision model to guide the choice of alternative tax reduction policies. © 2014 Wiley Periodicals, Inc. Naval Research Logistics, 61: 577–598, 2014  相似文献   
230.
We consider a discrete‐time groundwater model in which the cost of pumping takes a slightly different form to that which has been traditional in the research literature to date. This enables us to prove that (a) the optimal pumping quantity is nondecreasing in the ground water stock, (b) the stock level remaining after each period's pumping is also nondecreasing in the groundwater stock, (c) the optimal decision is determined by maximizing a concave function, and finally (d) the optimal pumping quantity is nonincreasing in the number of periods to go. We show that (a)–(c), while intuitive, do not hold under traditional modeling assumptions. We also explain the connections between our results and similar ones for some classic problems of operations research. © 2011 Wiley Periodicals, Inc. Naval Research Logistics 00: 000–000, 2011  相似文献   
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