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131.
换乘所产生的附加费用,如时间和票价等,导致配流影响因素产生变化,如果沿用传统方式将降低预测精度和可靠性。通过引入换乘次数和方式等因子计算出行等待、乘车、换乘及风险评估预留时间等,定义广义出行费用与计算方法;建立双层规划模型求解最优票价,最后通过算例分析弹性出行需求、换乘费用、票价之间的关系。计算结果表明,换乘费用对出行需求的影响小于票价优化对出行需求的影响,优化票价随换乘费用增加而加速降低,为公共交通票价优化提供研究依据。  相似文献   
132.
We investigated how people's recreational activities, values, and land use preferences are related to the protection level, biodiversity and cultural heritage values of nature-based tourism areas in northern Finland. We assessed peoples' opinions using a public participation geographic information system (PPGIS) and analyzed the data together with spatial biodiversity and cultural heritage data from the same area. Associations between the PPGIS place markings with the protection level and biodiversity values were quite low, and for the cultural heritage sites they were altogether missing. Negative preferences were often marked in areas with high numbers of sites rated as pleasant and they overlapped with each other, indicating conflicting preferences. Since most activities are not noticeably related to the protection level or biodiversity values of a site they can be planned so as to protect the biodiversity of the area.  相似文献   
133.
In this article we introduce a linear–quadratic volatility model with co-jumps and show how to calibrate this model to a rich dataset. We apply GMM and more specifically match the moments of realized power and multi-power variations, which are obtained from high-frequency stock market data. Our model incorporates two salient features: the setting of simultaneous jumps in both return process and volatility process and the superposition structure of a continuous linear–quadratic volatility process and a Lévy-driven Ornstein–Uhlenbeck process. We compare the quality of fit for several models, and show that our model outperforms the conventional jump diffusion or Bates model. Besides that, we find evidence that the jump sizes are not normally distributed and that our model performs best when the distribution of jump-sizes is only specified through certain (co-) moment conditions. Monte Carlo experiments are employed to confirm this.  相似文献   
134.
In a two-country Schumpeterian growth model, we study the incentives for basic research investments by governments in a globalized world. A country׳s basic research investments increase with the country׳s level of human capital and decline with its own market size. This may explain why some smaller countries invest so much in basic research. Compared with the optimal investments achievable when countries coordinate their basic research policies, a single country may over-invest in basic research. However, the total amount of decentralized basic research investments is always below the socially optimal investment level, which justifies policy coordination in this area.  相似文献   
135.
Many planning authorities and airports study measures to increase public transport use for airport ground access and egress. At the same time, an increase in real estate development at and around airports is occurring, both due to airports seeking new revenue possibilities and other developers attempting to profit from high value locations. This paper considers non-aeronautical activities at large airports, largely commercial centres and transit hubs, as land uses that have the potential to improve the situation for operating public transport services. In order to assess potential benefits and disadvantages, four research questions are considered: (1) Can the additional travel volume reach levels at which it has a significant impact? (2) To what extent do non-aeronautical activities influence the public transport access system? (3) Is the resulting demand distribution better or worse regarding peaking behaviour? (4) Is there a potential for the resulting overall demand to bring about capacity shortages?A case study is conducted at the airport of Zurich, Switzerland, which finds that non-aeronautical activities in the direct airport vicinity have led to a situation where the operation of public transport services is much more viable due to overall higher passenger numbers and a more even distribution throughout the day. It is concluded that locating non-aeronautical activities at airports can, in addition to providing commercial benefits to developers, lead to a situation where improved public transport services become feasible.  相似文献   
136.
福电秦皇岛北山宏福发电有限责任公司厂用照明系统进行改造。根据照明系统改造具体情况,本文从实际出发,对改造的背景、改造方案、和实现功能进行了重点介绍。  相似文献   
137.
The paper examines and compares the movements for promoting working-class savings in the modern USA and in Great Britain in the 19th century. It explores the use of savings as a technology for managing individuals’ behaviour and motives and the nature of the government objectives which are served by these parallel projects.  相似文献   
138.
We discuss the implications of an alternative to the efficient market hypothesis (EMH) the adaptive market hypothesis (AMH). The AMH advances a theoretical basis for a new financial paradigm which can better model such phenomena as the recent financial crisis. The AMH regards the financial market order as evolving, tentative and defined by creative destruction in which trading strategies are introduced, mutate to survive, or face abandonment. The concept of investor rationality is less helpful than the distinction between investment strategies which are more or less well adapted to the prevailing market environment. We outline how a more systematic and grounded basis for behavioural finance can be developed in line with the latter approach. Based on this we develop testable hypotheses allowing the AMH to be distinguished from the EMH. Finally, we discuss how the AMH can aid our understanding of important issues in finance. A central insight is that in the survival of richest, as opposed to fittest, implied by the AMH there is much room for misallocation of resources as price and value uncouple. In this shifting financial market order the regulatory State features as a further market in which the vote market verifies or disrupts market conditions.  相似文献   
139.
2016年5月《国务院办公厅关于深入推行科技特派员制度的若干意见》发布实施,但其实施效果如何有待验证。构建科技特派员制度实施绩效评估指标体系,利用改进熵值法和官方统计数据,对中国省域科技特派员制度实施绩效进行实证评估,并对评估结果进行聚类分析。结果表明,中国大多数省份科技特派员制度实施绩效水平较低;根据实施科技开发项目、形成利益共同体、服务农民情况、推广服务和扶贫成效5个绩效评估维度,可以将中国内地31个省份划分为5种类型;即使是总绩效水平较高的地区,在科技特派员制度实施绩效方面也存在一些短板。  相似文献   
140.
This paper examines the impact of parties and divided government on infrastructure expenditures for transportation, education, and social services in U.S. states. As infrastructure expenditures are considered a bi-partisan priority, we hypothesize that divided governments expand infrastructure spending compared to governments under true Democratic or Republican control. We test this hypothesis using U.S. state-level data over the period 1970 to 2008 and find that divided governments indeed increase expenditures for these budget categories. Specifically, divided governments spend more on transportation than unified Democratic governments, and more on education and social services than unified Republican governments. The effect is most pronounced for the core infrastructure of transportation and even stronger when only looking at capital outlays instead of total expenditures.  相似文献   
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