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11.
This article examines the puzzle of why futures prices continue to react to USDA crop reports despite the fact that reports appear to be no longer "newsworthy," that is, provide no better production estimates than private forecasts. The information value of reports is measured in terms of their influence on rational agents' harvest-time corn price expectations, which are uncovered using a Hamilton-type modeling approach. Results show that reports are still "newsworthy," as they would contribute to agents' price expectations if released a day early. Thus futures price reactions, which closely reflect price expectations, are rational and consistent with efficient markets hypothesis.  相似文献   
12.
This paper presents and analyses the differences in the eco-models implemented worldwide (such as whether and how carbon taxes being "recycled"), or in their efficiency parameters (inconsistent parameter values that account for different results). This is the assumption that a real tradeoff exists between the production of environmental goods. The present article empirically proves that something must be given up in order to gain something else, and once equations are specified to trace out the path of the economy over time, the natural economic formulation of such equations will embody the notion of economic and bio-tradeoffs.  相似文献   
13.
Stop and Go Agricultural Policies with a Land Market   总被引:1,自引:0,他引:1  
This article studies the design of farm policy in the presence of asymmetric information about farmers' productivity, a government objective to insure farmers a minimum "parity" income, an endogenous land rent, and diminishing returns on alternative (nonprogram crop) land uses. In this setting, acreage set asides are never part of an optimal farm policy, although compensated acreage limits are. When there are new farmer entrants who cannot be excluded from farm programs, optimal policy takes the form of a pure voluntary acreage limitation—or "buyout"—program in which high-cost producers participate and low-cost producers do not.  相似文献   
14.
The behaviour of stock prices on the Colombo Stock Exchange (CSE) is examined with a view to determine its consistency with the weak form of the Efficient Markets Hypothesis (EMH). Runs, Autocorrelation and Cointegration tests are applied to daily, weekly and monthly CSE index data for the period of January 1991–November 1996. Results of Runs, Correlation and Cointegration tests overwhelmingly reject the serial independence hypothesis, leading to the conclusion that the behaviour of stock prices in the Colombo Stock Exchange is not consistent with the weak form of the Efficient Markets Hypothesis. Tests of the-day-of-the-week-effect, however, show that there is no evidence of such a phenomenon on the Colombo Stock Exchange stock prices. Results of the tests of the-month-of-the-year-effect lead to the conclusion that CSE prices do not display any month-specific behaviour.  相似文献   
15.
This paper suggests an explanation for the heavy trading volumeobserved on the US capital markets, the world's largest. Heterodoxeconomic theory puts much of this volume down to speculation.Mainstream theory tends to support this thesis, either directlyor indirectly, by giving space to the idea that trading activityis for the most part exogenous to the functioning of the capitalmarkets. The central hypothesis of this paper is that the tradingvolumes observed are an endogenous feature of the capital markets,because they are to a great extent determined by the needs ofthe institutional investors who predominate on these markets.This endogeneity of trading is posited in connection with theemergence of a new ‘core–satellite’ paradigmin institutional investment, a development that essentiallymanifests the asset-management industry's transformation froma small industry serving a few wealthy clients to a mass industryserving large sections of the population.  相似文献   
16.
煤炭企业作为市场经营活动的主体 ,在竞争的环境下必须搞好煤炭营销“龙头”工作。煤炭市场营销是一个完整而科学的体系 ,其中的煤炭市场环境分析、用目标市场选择、煤炭营销组合设计则是这一体系中的“三大支柱” ,必须予以高度重视 ,以保证煤炭产品的适销对路和运销过程的快速、高效  相似文献   
17.
在北方,冬季施工一直是建筑业最为头疼的问题。某厂房装配车间大型设备基础需要冬季施工.其平面尺寸为44mx44m.最深处为-11.10m.最浅处为-2.73m。鉴于工期的要求及地基的越冬维护.选用了塑料暖棚法进行冬季施工。大棚内设简易采暖(利用厂房的暖风机设备)。白天利用太阳能提高棚内温度.夜间视气温情况间歇供暖。以保持坑底的温度在0℃以上。实践证明.太阳能暖棚法冬季施工效果很好.从大棚的物质用量及使用效果上看.非常适用于北方大中型地下工程的冬季施工。  相似文献   
18.
余妍 《科技和产业》2024,24(12):261-270
利用相变储能装置的储能特性,针对热量传输过程中的热延迟与热衰减,建立了考虑热惯性特征的含相变储能热泵的综合能源系统优化调度模型,并采用预测平均评价PMV指标来量化热负荷弹性。运用Dymola与Matlab联合建模,以经济运行总成本为目标函数,对比分析三种不同场景下综合能源系统的削峰填谷能力、可再生能源消纳能力、环境效益与安全性,对冬季典型日进行24小时运行策略优化。算例分析结果表明,考虑热惯性与热负荷弹性的含相变储能热泵的综合能源系统具有更好的经济性与抗故障能力,相较于含常规储热水箱的综合能源系统经济运行总成本降低了6.6%,抗供热故障时间延长3.51h。  相似文献   
19.
China's sustained rapid economic growth and development has contributed to the surge in consumption and production of livestock in that country  termed the livestock revolution. Consumption trends are first reviewed, and changes in food consumption patterns include a marked shift away from grains and towards meats and dairy products. A question is to what extent this rapid increase in demand for livestock products is reflected in China's agri‐food trade statistics? While her agri‐food imports have dramatically increased since China's accession to the WTO, livestock products have not made a noticeable contribution, although the import of certain animal feedstuffs has. This implies China's continuing self‐sufficiency in most livestock products. The paper next considers developments in China's livestock farming sector and policies that have been contributing to these supply‐side developments. The paper concludes with an examination of issues that may be important to the future development of China's, and the world's, livestock situation;  this includes future demand developments, and the question of whether future demand growth in China might be met with local production, imports of final product, and/or imports of feedstuffs.  相似文献   
20.
贸易摩擦和能源革命正驱动国际能源市场格局悄然发生变化,能源安全再一次成为各国关注的焦点.作为能源进口大国和隐含能源净出口大国,我国由于缺失国际能源定价权经常被动接受"中国溢价"而蒙受巨大损失.研究发现,我国缺失国际能源定价权的原因主要在于能源期货市场发展滞后,能源战略储备不足,人民币国际化程度较低,行业垄断度较高.面对...  相似文献   
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