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691.
The problems of labor staffing and scheduling have received substantial attention in the literature. We introduce two new models of the labor staffing and scheduling problems that avoid the limitations of existing models. Collectively, the models have five important attributes. First, both models ensure the delivery of a minimally acceptable level of service in all periods. Second, one model can identify the least expensive way of delivering a specified aggregate level of customer service (the labor staffing problem and a form of labor scheduling problem). Third, the other model can identify the highest level of service attainable with a fixed amount of labor (the other form of the labor scheduling problem). Fourth, the models enable managers to identify the pareto relationship between labor costs and customer service. Fifth, the models allow a degree of control over service levels that is unattainable with existing models. Because of these attributes, which existing models largely do not possess, we expect these models to have broad applicability in a wide range of organizations operating in both competitive and noncompetitive environments. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 719–740, 1997  相似文献   
692.
How do states use nuclear weapons to achieve their goals in international politics? Nuclear weapons can influence state decisions about a range of strategic choices relating to military aggression, the scope of foreign policy objectives, and relations with allies. The article offers a theory to explain why emerging nuclear powers use nuclear weapons to facilitate different foreign policies: becoming more or less aggressive; providing additional support to allies or proxies, seeking independence from allies; or expanding the state’s goals in international politics. I argue that a state’s choices depend on the presence of severe territorial threats or an ongoing war, the presence of allies that provide for the state’s security, and whether the state is increasing in relative power. The conclusion discusses implications of the argument for our understanding of nuclear weapons and the history of proliferation, and nonproliferation policy today.  相似文献   
693.
Existing models in multistage service systems assume full information on the state of downstream stages. In this paper, we investigate how much the lack of such information impacts jobs' waiting time in a two‐stage system with two types of jobs at the first stage. The goal is to find the optimal control policy for the server at the first stage to switch between type‐1 and type‐2 jobs, while minimizing the long‐run average number of jobs in the system. We identify control policies and corresponding conditions under which having no or partial information, the system can still capture the most benefit of having full information.  相似文献   
694.
In the mid-2000s, the United States Army was embroiled in counterinsurgency missions in Iraq and Afghanistan that required deeper understanding of local social systems. The Army turned to systems thinking and design thinking to model and understand the world, define problems, and develop approaches to strategic and operational challenges. However, the Army’s approach as expressed in publications and doctrine encourages the development of complicated, unsupported, and unfalsifiable hypotheses. The risk is that the Army will act on incorrect assumptions and develop plans that are fragile.  相似文献   
695.
Norway, Sweden and Finland have proclaimed a willingness to cooperate militarily in a future crisis or conflict despite their diverging alliance affiliation. This article assesses their ability to do so through various elements affecting their interoperability, with Arctic Challenge, a multinational military exercise, as an empirical basis. The analysis finds that the NATO/non-NATO-divide has a negative impact on the trilateral defence cooperation, especially on exchange of information and aspects related to command and control. At the same time, Finland and Sweden have become largely NATO-standardized through their active partnership with the Alliance. This has affected interoperability aspects, such as communication, culture, and the compatibility of technical solutions, in a positive manner. Through agreements with the Alliance, as well as domestic legal changes, the two NATO-partners have facilitated receiving military assistance from Norway and other NATO-members during a crisis. Other agreements between the Nordic countries, however, have been limited to peacetime.  相似文献   
696.
Despite multiple base closing rounds, the United States Department of Defense still has excess base capacity, and thus President Trump and high-level Defense Department officials are calling for more base closure through the Base Realignment and Closure (BRAC) process. However, another BRAC may not be the optimal solution, because simple base closure is not an efficient way to reduce surplus base capacity. Thus, Defense Department officials should consider other methods to reduce surplus capacity, including reduction in base size, leasing excess base property, or transferring it to another government agency for a variety of alternative uses. The surplus capacity issue also offers an opportunity to DOD to reassess base utilization, to update base requirements with current and future force structure. While BRAC focuses on American military bases, the process and alternatives also have international applications.  相似文献   
697.
Do Private Military and Security Companies (PMSCs) impact peace duration after civil war? I argue that the role these organisations play in a conflict can impact post-conflict stability. Specifically, I suggest that variance in services provided by PMSCs can influence rebels’ calculations about relative capabilities. These calculations then contribute to the probability for civil war recurrence. Building on the bargaining framework, with a focus on information and commitment problems, this article demonstrates that PMSCs participating in armed combat operations can jeopardise the stability of peace following civil war. Three case narratives (Angola, Sierra Leone and Croatia) are used to probe the theoretical argument and results are illustrative – PMSCs serving as force multipliers contribute to an increase in the probability for conflict recurrence.  相似文献   
698.
Many observers anticipate “arms races” between states seeking to deploy artificial intelligence (AI) in diverse military applications, some of which raise concerns on ethical and legal grounds, or from the perspective of strategic stability or accident risk. How viable are arms control regimes for military AI? This article draws a parallel with the experience in controlling nuclear weapons, to examine the opportunities and pitfalls of efforts to prevent, channel, or contain the militarization of AI. It applies three analytical lenses to argue that (1) norm institutionalization can counter or slow proliferation; (2) organized “epistemic communities” of experts can effectively catalyze arms control; (3) many military AI applications will remain susceptible to “normal accidents,” such that assurances of “meaningful human control” are largely inadequate. I conclude that while there are key differences, understanding these lessons remains essential to those seeking to pursue or study the next chapter in global arms control.  相似文献   
699.
The Colombian civil war lasted for nearly six decades with approximately 10 percent of its population being displaced over the same period. The implications of this conflict have transgressed international boundaries. Countries such as Ecuador experienced an exodus of victims as well as an increase in the presence of armed groups, along with the proliferation of illegal businesses. Even though the internal social and economic consequences of the Colombian conflict have been documented in the literature, there is yet to be a study addressing these issues from the perspective of impacted neighboring countries. In this work, we contribute to the literature by evaluating whether the influx of asylum seekers and the increasing presence of armed groups in the bordering provinces of Ecuador have lead to an increase in violence among these provinces. We do not find any link between the arrival of asylum seekers and the incidence of violent crimes in the Ecuadorean bordering provinces. Similarly, our results indicate that despite an increase in the presence of armed groups, these regions did not experience an increase in the homicide rates significantly different from the other provinces. The results are robust to various specifications and econometric techniques.  相似文献   
700.
We consider a two‐level system in which a warehouse manages the inventories of multiple retailers. Each retailer employs an order‐up‐to level inventory policy over T periods and faces an external demand which is dynamic and known. A retailer's inventory should be raised to its maximum limit when replenished. The problem is to jointly decide on replenishment times and quantities of warehouse and retailers so as to minimize the total costs in the system. Unlike the case in the single level lot‐sizing problem, we cannot assume that the initial inventory will be zero without loss of generality. We propose a strong mixed integer program formulation for the problem with zero and nonzero initial inventories at the warehouse. The strong formulation for the zero initial inventory case has only T binary variables and represents the convex hull of the feasible region of the problem when there is only one retailer. Computational results with a state‐of‐the art solver reveal that our formulations are very effective in solving large‐size instances to optimality. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
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