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31.
随着我国经济的快速发展,国家越来越重视现有的专业性的有线火灾报警系统的管理和控制,为了进一步的提升火灾报警系统中的信息传输管理效率,及时有效地发现和分析火灾的实际情况,必须要提高建筑物的防火能力。因此,论文主要针对现阶段的ZigBee技术在火灾自动报警系统中的应用进行简要分析,并提出合理化建议。  相似文献   
32.
The objective of this article is twofold: first, investigating the relationship between technical efficiency and decoupled direct payments of a sample of Italian farms prior to the application of the 2014–2020 Common Agricultural Policy reform; second, evaluating possible implications of alternative scenarios about distribution of direct payments on technical efficiency. To these aims, a stochastic frontier analysis is adopted. Results indicate that direct payments produce significant effects on technical efficiency in specialized farms, which received higher levels of support. However, effects are contrasting. Moreover, results show that redistribution of policy subsidies may negatively impact on technical efficiency to an extent depending upon the criterion of redistribution applied. Finally, some policy suggestions are given.  相似文献   
33.
电力企业在移动信息化技术方面也迈出了步伐,开展电力业务现场作业、物资与基建的现场作业、故障抢修等班组作业应用,本文主要讨论移动应用平台的运维和技术管控工作,为移动应用平台的建设和发展提供一种工作思路。  相似文献   
34.
[目的]全面分析城乡居民基本养老保险制度对农村家庭各项消费支出现状的影响,就进一步完善该项政策和稳定农村消费市场提供重要的理论参考。[方法]文章以消费和储蓄生命周期理论为分析框架,通过选取合理的样本面板数据,运用系统GMM回归分析方法探究了城乡居民基本养老保险制度对农村家庭消费支出水平的影响。[结果]财产性收入是影响农民参与城乡居民基本养老保险制度的主要因素以及投保档次的制约因素,作以存量财富为基础的财产性收入要比流量形式存在的财富具有更强抵御风险的能力,即财产性收入在很大程度上可以增加农村家庭对养老保险的依赖程度。另外,城乡居民基本养老保险制度对农村家庭消费能力表现出异质性影响。其中,城乡居民基本养老保险制度对农村家庭生活消费支出、食品性等日常性支出、文体消费支出水平明显要高于对医疗消费支出水平。[结论]国家要加大宣传城乡居民基本养老保险制度的积极和辐射作用,让广大农村家庭能够真正了解这项政策的意图。同时,要逐步破解城乡二元结构等制度性障碍,让更多农村家庭能够享受到与城镇居民相同的养老待遇。  相似文献   
35.
With the acceleration of China’s urbanization, the functions and benefits of mega-projects are required higher. With the deepening of “the Silk Road Economic Belt and the 21st-Century Maritime Silk Road”, the quantitative evaluation of multinational investment projects will help strengthen cross-border communication among government, society and enterprises, which provide a basis for mutual trust. This study empirically analyzes and evaluates the impact of mega-projects on carrying capacity of cities, by using the DID method based on the panel data of 15 cities in China from 2000 to 2013. The results show that the construction and operation of the first-line project of the West-East gas pipeline has a significant positive impact on the improvement of carrying capacity of cities along the line. However, the degree of impact on three dimensions is slightly different. The impact on the social carrying capacity is the greatest, then the ecological and economic carrying capacity. Therefore, the decisions of domestic mega-projects should be unified with urban planning to promote the sustainable development of China’s economy and social. The investment of mega-projects abroad should also be coordinated with the carrying capacity of host cities, in order to enhance the competitiveness and creativity of Chinese multinational mega-projects investment.  相似文献   
36.
ABSTRACT

The implications of national or regional energy policies for technical efficiency and environmental outcomes in electricity generation depend on fossil fuel input substitution. This study uses state level data to examine fossil fuel (coal and natural gas) substitution in electricity generation under increased availability of natural gas in the United States. We observe that changes in elasticities of substitution from pre-2009 to post-2009 differ across states suggesting that the effects of increased availability of inexpensive natural gas on electricity generation have been spatially heterogeneous. We rely on the observed heterogeneity to assess the effects of fossil fuel input substitution on technical efficiency and CO2 emissions. The results reveal that state level elasticity of substitution between natural gas and coal has a positive effect on technical efficiency and a negative effect on CO2 emissions. Therefore, future policy design and analyses should reflect the implications for regional elasticities of fossil fuel substitution and associated environmental outcomes.  相似文献   
37.
In austerity times, the general interest to reduce costs and improve efficiency levels often resulted into local cuts to public expenditure and profound reorganizations of existing service networks, especially in sectors like healthcare. In Italy, a recent reform prescribed the reconfiguration of time-dependent (i.e. emergency) hospital networks with the aim of improving patients’ accessibility conditions. In order to evaluate the impacts determined by this reorganization, we perform a spatial analysis in which we consider the distance from the closest facility as an accessibility measure. Results obtained from the spatial analysis confirm that users effectively benefit from the reorganization process but also that further improvements are possible, especially for the worst served ones. To this end, we also propose solving a mathematical programming model aiming at redistributing the capacities, i.e. the supply of beds, among the hospitals of the network seeking to maximize users’ accessibility. The realized computational experiments show that averagely better and even more equitable accessibility conditions could be obtained by containing the deriving reorganization costs.  相似文献   
38.
[目的]蛋鸡养殖场规模化养殖与生态环境保护协调发展问题是蛋鸡养殖业可持续发展过程中面临的关键性问题,测度我国大、中、小3种规模下不同省份蛋鸡养殖场的环境全要素生产率,并从时间、地区两个维度对蛋鸡养殖场的环境全要素生产率进行比较。[方法]利用2004—2016年不同养殖规模蛋鸡养殖场的投入和产出数据,文章基于SBM函数的Malmquist Luengerber(ML)指数方法,对蛋鸡养殖场环境全要素生产率进行分解,将其分解为技术进步指数、效率改进指数。[结果](1)蛋鸡养殖场环境全要素生产率整体呈现下降趋势,同时与蛋鸡养殖规模呈反比,蛋鸡养殖场规模越大,蛋鸡养殖环境生产率越小。(2)蛋鸡养殖场效率存在效率改善,但养殖技术进步率相对较低,尤其是对小规模养殖场而言,改善空间更明显; (3)蛋鸡养殖环境全要素生产率区域差异较为明显,整体来看,蛋鸡养殖主产区环境全要素生产率高于非主产区。[结论]加强蛋鸡产业科技创新水平以及公共服务设施的投入,提高养殖户的废弃物无害化处理能力,推行蛋鸡养殖的规模化和标准化发展,进一步改善养殖效率,以促进蛋鸡养殖规模化和生态环境保护协调发展。  相似文献   
39.
Airport capacity constraints are increasingly challenging the growth of air traffic. At the same time, decision-making about airport capacity investments is extremely complex, involving trade-offs. This paper’s objective is to optimise a privately owned airport system’s capacity investment decision in a city under demand uncertainty. Next to the investment size, our real options model incorporates the timing of the investment, as well as the cost of congestion. The results reveal that the larger a city’s initial airport capacity, the smaller its investment will relatively be and the lower the occupancy rate threshold at which investment will take place. We also show that, in case of a higher demand growth combined with more demand uncertainty, the city will benefit from a significantly larger investment, but made later at a higher occupancy rate. In this case, cities with a small initial capacity will sometimes even more than double current capacity. Higher airport charges and an increase in non-aeronautical revenues both lead to a later investment in more capacity, due to the increased project attractiveness. An increase in congestion costs results in a larger investment made earlier, in order to eliminate delays. Airport operational cost and capacity holding cost increases both lead to smaller investments.  相似文献   
40.
This paper discusses the situation of China's air cargo sector facing the COVID-19 pandemic. Based on the expectation that it can go out of recession more easily than China's air passenger sector, this paper analyzes four aspects that are favorable and unfavorable for its further development: (1) strengths (China's sustainable economic basis and proliferating cargo suppliers), (2) weaknesses (insufficient cargo capacity and less business internationalization), (3) opportunities (top authority support, rising e-commerce demand, and new technological momentum), and (4) challenges (uncertain trade environment and increasing profitability pressure). Then this paper suggests strategies for China's air cargo suppliers to adapt to the pandemic.  相似文献   
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