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231.
The March 2012 coup in Mali opened the door to expanded territorial occupation in northern Mali by Tuareg separatists and subsequently armed Islamist extremists. French forces intervened at the behest of the interim government in Mali. This article examines how various actors frame the conflict to their advantage. While the Malian government and France are allies, the position of various Tuareg actors shift over time as they strategize and weigh the value of allegiance with the French. Local extremist organizations are labeled as terrorists and are targeted as enemies. This article argues that the conflict has been decontextualized and framed within the ‘war on terror’. France’s decision to intervene and to expand their regional military presence, rather than exit, is legitimized by the framing of their intervention as integral to counterterrorism efforts.  相似文献   
232.
Following a review of the basic ideas in structural reliability, including signature‐based representation and preservation theorems for systems whose components have independent and identically distributed (i.i.d.) lifetimes, extensions that apply to the comparison of coherent systems of different sizes, and stochastic mixtures of them, are obtained. It is then shown that these results may be extended to vectors of exchangeable random lifetimes. In particular, for arbitrary systems of sizes m < n with exchangeable component lifetimes, it is shown that the distribution of an m‐component system's lifetime can be written as a mixture of the distributions of k‐out‐of‐n systems. When the system has n components, the vector of coefficients in this mixture representation is precisely the signature of the system defined in Samaniego, IEEE Trans Reliabil R–34 (1985) 69–72. These mixture representations are then used to obtain new stochastic ordering properties for coherent or mixed systems of different sizes. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
233.
A single server is faced with a collection of jobs of varying duration and urgency. Each job has a random lifetime during which it is available for nonpreemptive service. Should a job's lifetime expire before its service begins then it is lost from the system unserved. The goal is to schedule the jobs for service to maximize the expected number served to completion. Two heuristics have been proposed in the literature. One (labeled πS) operates a static priority among the job classes and works well in a “no premature job loss” limit, whereas the second (πM) is a myopic heuristic which works well when lifetimes are short. Both can exhibit poor performance for problems at some distance from the regimes for which they were designed. We develop a robustly good heuristic by an approximative approach to the application of a policy improvement step to the asymptotically optimal heuristic πS, in which we use a fluid model to obtain an approximation for the value function of πS. The performance of the proposed heuristic is investigated in an extensive numerical study. © 2010 Wiley Periodicals, Inc. Naval Research Logistics 2010  相似文献   
234.
This paper describes modeling and operational analysis of a generic asymmetric service‐system situation in which (a) Red agents, potentially threatening, but in another but important interpretation, are isolated friendlies, such as downed pilots, that require assistance and “arrive” according to some partially known and potentially changing pattern in time and space; and (b) Reds have effectively limited unknown deadlines or times of availability for Blue service, i.e., detection, classification, and attack in a military setting or emergency assistance in others. We discuss various service options by Blue service agents and devise several approximations allowing one to compute efficiently those proportions of tasks of different classes that are successfully served or, more generally, if different rewards are associated with different classes of tasks, the percentage of the possible reward gained. We suggest heuristic policies for a Blue server to select the next task to perform and to decide how much time to allocate to that service. We discuss this for a number of specific examples. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.  相似文献   
235.
This article is concerned with the determination of pricing strategies for a firm that in each period of a finite horizon receives replenishment quantities of a single product which it sells in two markets, for example, a long‐distance market and an on‐site market. The key difference between the two markets is that the long‐distance market provides for a one period delay in demand fulfillment. In contrast, on‐site orders must be filled immediately as the customer is at the physical on‐site location. We model the demands in consecutive periods as independent random variables and their distributions depend on the item's price in accordance with two general stochastic demand functions: additive or multiplicative. The firm uses a single pool of inventory to fulfill demands from both markets. We investigate properties of the structure of the dynamic pricing strategy that maximizes the total expected discounted profit over the finite time horizon, under fixed or controlled replenishment conditions. Further, we provide conditions under which one market may be the preferred outlet to sale over the other. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 531–549, 2015  相似文献   
236.
The anthrax attacks of 2001 energized research directed toward reducing health consequences from airborne contaminants by augmenting current heating ventilation and air-conditioning (HVAC) systems. Even during peacetime, interest will continue in improving HVAC components to reduce biocontaminants associated with sick building syndrome. Current HVAC design uses numerical simulation methods of ordinary differential equations to predict approximate performance. The authors show that state-space Laplace Transform calculations actually solve the underlying differential equations and yield algebraic expressions that provide new insight. To sharpen the arguments in favor of this methodology, attention is restricted to improving existing HVAC systems to increase protection from an external release of hazardous particulates. By nearly eliminating the need for dynamical simulation, the resulting methods can be applied to far more complex HVAC designs with little additional computational effort. The new methods reduce the time required for computation by three orders of magnitude. These algebraic methods also can be extended to disparate technical problems including internal particulate release, gas masks, and designing new protective buildings.  相似文献   
237.
Irrespective our views on the rationality of our opponent's continuing to conduct operations against us, unless utterly extirpated, he retains a vote on when and how conflict will end. This is because war is about power — compelling another actor to do something he would not otherwise do, or to cease doing something he would otherwise prefer to do. In planning for conflict termination we should account for the peculiarities of opponents who may decide not to quit when we have beat them fair and square. We do not desire that they cease conventional fighting, but that they cease fighting altogether.  相似文献   
238.
This article borrows from the work of Clausewitz to posit two general approaches to the pursuit of limitation in war, one being political and the other technical. The political approach seeks to control escalation via consensual arrangements with the adversary, while the technical approach seeks to forestall escalation by peremptorily destroying the enemy's military capability. It is argued that the 'Revolution in Military Affairs' (RMA) instantiates the second, technical, approach to war limitation. By exploiting advanced technology, the US armed forces hope to limit the costs of war by defeating their adversaries in a rapid, decisive manner. The problems associated with this approach are discussed in relation to the nature of the conflicts that the US is likely to face in the foreseeable future. The article concludes by suggesting that such conflicts will require that more attention be paid to the political sources of limitation in war.  相似文献   
239.
240.
The aim of this article is to consider how Algeria's most prized achievement and treasured memory – the FLN's victory over the French in the war of liberation – has helped stimulate and sustain the violence that has blighted the country since independence. It argues that successive governments have propagated a legend of the war that encourages and legitimises rebellion and armed resistance. By celebrating the actions and achievements of a committed band of revolutionaries they have established a precedent whereby it is every citizen's duty to oppose and resist an unjust government. Time and again therefore, insurgent groups like the FFS, MIA, and AIS have justified their actions and won popular support by portraying themselves as the early FLN's natural heir.  相似文献   
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