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Decades ago, simulation was famously characterized as a “method of last resort,” to which analysts should turn only “when all else fails.” In those intervening decades, the technologies supporting simulation—computing hardware, simulation‐modeling paradigms, simulation software, design‐and‐analysis methods—have all advanced dramatically. We offer an updated view that simulation is now a very appealing option for modeling and analysis. When applied properly, simulation can provide fully as much insight, with as much precision as desired, as can exact analytical methods that are based on more restrictive assumptions. The fundamental advantage of simulation is that it can tolerate far less restrictive modeling assumptions, leading to an underlying model that is more reflective of reality and thus more valid, leading to better decisions. Published 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 293–303, 2015  相似文献   
354.
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   
355.
Vietnam was a complex conflict, which historians and political scientists have struggled to understand. Some of the bitterest disputes in the historiography revolve around the US approach to counterinsurgency in Vietnam. Many different facets of the war have received the attention of filmmakers, and an examination of their work suggests new ways of thinking about the conflict. This article considers film portrayals of three phases of the Vietnam War – firstly, the early period of ‘political action’, then the advisory period, and finally the Americanization of the war after 1965. It suggests that by examining the experiences of participants in each of these phases, Vietnam War cinema helps to illustrate the problems that faced various American approaches to counterinsurgency in the conflict. Combined with the importance of films in determining popular perceptions of both historical conflicts and counterinsurgency in general, it suggests that they are worthy subjects of study and critique.  相似文献   
356.
A range of theories have sought to explain and predict secession with varying degrees of success. Arguing that a disproportionate focus upon the seceding group as the unit of analysis has frustrated the development of a comprehensive theoretical framework that is universally valid, this article highlights the role of predecessor institutions of governance and the failure of states to successfully incorporate these as an important, but neglected, causal factor in the study of secession. The inclusion of pre-state institutions of governance and processes of state formation not only results in a more complete, and therefore accurate, explanatory account of secession, but also explains why some regions have been more prone to secession than others.  相似文献   
357.
The goal of this paper is to investigate the relationship between type of welfare regimes and military expenditures. There is a sizeable empirical literature on the development of the welfare state and on the typology of the welfare regimes. There appear to be, however, no empirical studies that examine welfare regimes with special attention to military spending. This study aims at providing a comprehensive analysis on the topic by considering several different welfare regime typologies. To do so, we use dynamic panel data analysis for 37 countries for the period of 1988–2003 by considering a wide range of control variables such as inequality measures, number of terrorist events, and size of the armed forces. We also replicate the same analyses for the political regimes. Our findings, in line with the literature, show that there is a positive relationship between income inequality and share of military expenditures in the central government budget, and that the number of terrorist events is a significant factor that affects both the level of military expenditure and inequality. Also, the paper reveals a significant negative relationship between social democratic welfare regimes and military expenditures.  相似文献   
358.
This paper analyzes defense spending preferences using ordered logit regression analysis of American National Election Survey data from 1980 through 2008. Our results indicate that as opposed to having the ideology of isolationism, political party identification towards the Republican Party or having economic stakes in defense spending always play a significant role in increased preference towards defense spending. Demographic groups such as Native Americans, Hispanics, and retired women, a demographic subgroup, display generally positive preferences towards defense spending. Somewhat surprisingly, another demographic subgroup, ‘security moms,’ do not show a preference. Our analysis also displays lower (higher) preference in the early 1990s (2000s) for defense spending compared to the year 2008.  相似文献   
359.
Fodei J. Batty 《Civil Wars》2015,17(3):379-407
The utility of post-conflict elections in sub-Saharan Africa has been the subject of lively academic and policy debates. While some scholars associate several electoral outcomes with votes for peace, others argue that post-conflict elections exacerbate existing cleavages and could reproduce the conditions that led to civil war if the right electoral system is not employed. This paper examines these contesting claims using electoral data in a comparative study of the first truly post-conflict elections in Sierra Leone and Liberia. The analysis shows that political leaders in both countries received votes across numerous cleavage lines in contradiction with an ethnic census.  相似文献   
360.
Up to the present, there is only very little research on how the population perceives terrorism and its threats, even though support from the population is crucial for effective counterterrorism. By eliciting beliefs and subjecting them to content analyses, six factors were found that determine the protection worthiness of a target in the people's view: the potential damage to “people,” “symbolism,” “economy,” “politics,” “nature,” and “image/publicity.” These empirically found factors are in line with factors specified by terrorist target selection models. They differ in the strength of their cognitive representation among participants and, thus, their subjective importance to the people. The first three factors are shared among all participants, whereas the latter ones could only be found in a part of the participant sample. People's judgments of the targets' protection worthiness differ substantially from their judgments of the targets' attractiveness to terrorists, even though the same factors seem to be involved. This study offers an insight into the people's mental model about protection worthiness of targets. Together with classical risk analysis and knowledge about terrorists, these results can form a basis for setting up a holistic scheme for critical infrastructure protection.  相似文献   
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