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251.
The Replenishment at Sea Planner (RASP) is saving the U.S. Navy millions of dollars a year by reducing fuel consumption of its Combat Logistics Force (CLF). CLF shuttle supply ships deploy from ports to rendezvous with underway U.S. combatants and those of coalition partners. The overwhelming commodity transferred is fuel, ship‐to‐ship by hoses, while other important packaged goods and spare parts are high‐lined, or helicoptered between ships. The U.S. Navy is organized in large areas of responsibility called numbered fleets, and within each of these a scheduler must promulgate a daily forecast of CLF shuttle operations. The operational planning horizon extends out several weeks, or as far into the future as we can forecast demand. We solve RASP with integer linear optimization and a purpose‐built heuristic. RASP plans Replenishment‐at‐Sea (RAS) events with 4‐hour (Navy watch) time fidelity. For five years, RASP has served two purposes: (1) it helps schedulers generate a daily schedule and animates it using Google Earth, and (2) it automates reports command‐to‐ship messages that are essential to keep this complex logistics system operating.  相似文献   
252.
This article examines challenges in international nuclear safeguards pertaining to the timely detection of highly enriched uranium production at large-scale gas centrifuge enrichment plants. To establish where present gas centrifuge enrichment plant safeguards measures and approaches could be strengthened, we have created a discrete time model for simulating hypothetical misuse scenarios, both through transient phases and at steady-state. We find that timely detection of misuse at modern large-scale facilities presents a challenge for international safeguards. A toolbox of unattended measurement systems, along with remote monitoring, however, could be used to improve detection timeliness, enabling the initiation of follow-up activities, potentially on a rapid time scale. These measures, which would need very low false alarm rates, should be implemented in a graded approach, depending on the characteristics of each enrichment plant and an analysis of plausible acquisition paths for the State in which it is situated. Some of these technologies could provide significant benefit to plant operators.  相似文献   
253.
Arms transfers provide exporters an avenue to provide security to other states while gaining economic benefits. Arms transfers provide importers an avenue to gain security without having to rely on alliances. Past research uses aggregate measures of the monetary or security value of major weapon system transfers without accounting for strategic differences in possible use in interstate and civil conflict. This article presents a data set on interstate transfers of major weapon systems between 1950 and 2010 building upon Stockholm Peach Research Institute’s Arms Trade Register with several improvements. First, it disaggregates land weapons and air weapons into categories reflecting their strategic capabilities. Second, model level characteristics (e.g. age, speed, and range) are drawn from Jane’s Defence sources. Additionally, the data set covers a larger range of time and states than previous data sets categorizing arms. To demonstrate the usefulness, this article first presents summary statistics of the data set and then replicates an earlier test to show that the effect of human rights and regime types on United States transfers differs across the categories of arms compared to alternative measures of arms transfers.  相似文献   
254.
MOZAMBIQUE     
Mozambique is widely regarded as a success story. The parliamentary and presidential lections in 1994 marked the peak of the peace process in Mozambique. Despite minor irregularities, the elections were declared free and fair by international observers. Mozambique has succeeded where other countries such as Angola has failed—a stable peace process, multiparty elections and the transformation of the armed opposition into a civil political party. Its transition to liberalism and capitalism brought macro-economic growth rates that are probably envied by many countries in the region. This article argues, however, that Mozambique provides an example of a third wave democracy where the transition from in electoral democracy to a consolidated democracy has not yet been completed, with little progress towards democratic maturity. In particular, the repercussions of the elections in 1999, Mozambique's ‘black’ November in 2000 and the process of recent consultation between the and Frelimo leadership in order to resolve the paralysed state of Mozambican politics underline a tendency towards a permanent entrenchment of democratic minimalism.  相似文献   
255.
This paper aims at forecasting the burden on the Greek economy resulting from the arms race against Turkey and at concentrating on the leading determinants of this burden. The military debt and the defence share of GDP are employed alternatively in order to approximate the measurement of the arms race pressure on Greece, and the method used is that of artificial neural networks. The use of a wide variety of explanatory variables in combination with the promising results derived, suggest that the impact on the Greek economy resulting from this arms race is determined, to a large, extent, by demographic factors which strongly favour the Turkish side. Prediction on both miltary debt and defence expenditure exhibited highly satisfactory accuracy, while the estimation of input significance, indicates that variables describing the Turkish side are often dominant over the corresponding Greek ones.  相似文献   
256.
Whose preferences determine the tradeoff between security and civilian output in deciding upon budget allocations to defence? This paper considers the role that consumer preferences might play in influencing military spending. We propose normative criteria to judge the economic or political efficiency of defence provision at a given time, and test them using Australian survey‐based micro‐data. Our results suggest that the political system has not delivered a simple social‐choice translation of individual preferences into collective outcomes, nor has it delivered results consistent with simple majority‐voting median preferences.  相似文献   
257.

This paper presents a model for converting legacy defense production facilities into private‐sector economic resources. Specifically, this paper will examine as a case study the first successful conversion of a former U.S. Department of Energy nuclear weapons production installation, including reasons for its success, its costs and benefits, and lessons for public policy. It is envisioned that this model may be useful for mitigating local economic hardship resulting from defense “downsizing” and for privatizing production capacities critical for national defense.  相似文献   
258.

Since 1975 “offsets” have begun to appear frequently in contracts covering international sales of aircraft and other products incorporating advanced technology. Offsets involve reciprocity beyond that normally found in an exchange of goods for money. They may involve co‐production or co‐design of the principal item to be exchanged, or acceptance by the seller of goods or services unrelated to it as partial payment (indirect offsets or countertrade).

The United States has become the major provider of offsets and anti‐offset sentiment has grown. Economists interpret them as trade diverting. Politicians from regions suffering loss of employment view them as bestowing unfair advantage to foreign competitors.

The authors examine offsets from both theoretical and policy perspectives and conclude that in such noncompetitive markets, second‐best considerations dominate, requiring case‐by‐case evaluation of impacts and rendering across‐the‐board determinations of welfare loss suspect.  相似文献   
259.
This paper models and estimates Greek defence spending over the 1950–1989 period. It employs the Stone‐Geary welfare function and estimates levels of defence expenditures by the Engle‐Granger two‐step procedure. The Dickey‐Fuller test regression for cointegration is specified in terms of the significance of additional augmentations. The Deaton‐Muellbauer functional form is then employed and an estimating equation for the expenditure share of defence is derived. This specification is compared with the levels equation through a number of non‐nested tests involving model transformation.  相似文献   
260.
Why should deployment affect re‐enlistment? In our model, members enter the military with naïve beliefs about deployment and use actual deployment experience to update their beliefs and revise their expected utility of re‐enlisting. Empirically, re‐enlistment is related to the type and number of deployments, consistent with the learning model. Non‐hostile deployment increases first‐term re‐enlistment but hostile deployment has little effect except for the Army, where the effect is positive. Both types increase second‐term re‐enlistment. Interestingly, first‐term members with dependants tend to respond to deployment like second‐term members. In addition, deployment acts directly to affect re‐enlistment, not indirectly through time to promotion.  相似文献   
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