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971.
Understanding the emergence of innovation systems is recently put central in research analysing the process of technological change. Especially the key activities that are important for the build up of an innovation system receive much attention. These are labelled ‘functions of innovation systems’. This paper builds on five empirical studies, related to renewable energy technologies, to test whether the functions of innovation systems framework is a valid framework to analyse processes of technological change. We test the claim that a specific set of functions is suitable. We also test the claim made in previous publications that the interactions between system functions accelerate innovation system emergence and growth. Both claims are confirmed.  相似文献   
972.
This paper estimates the impact of demographic change on energy use and greenhouse gas emissions in Germany. Since old people display different consumption patterns than young people, an increase in the proportion of old people affects overall consumption patterns. Micro data from a household survey are used to identify age-specific consumption patterns and to project the impact of demographic change on the structure of total consumption expenditure up to the year 2030. The resulting final demand vectors are entered into an environmental input-output model, which allows the calculation of sectoral production, energy use and greenhouse gas emissions. The model results suggest that until 2030, demographic change raises the share of methane in total greenhouse gas emissions and does not contribute to reducing energy use and greenhouse gas emissions in Germany. The model is also used to explore the effects of redistributing income between age groups and a policy-induced switch from motor vehicle use to public transport.  相似文献   
973.
This paper presents a basin scale analysis of the Nilüfer River Basin of Turkey, where agricultural, urban, and environmental users compete for scarce water in an environment where climate change and food security present large and growing challenges. It presents results of a basin scale dynamic nonlinear programming model that addresses economic efficiency, climate change, and food security. Its approach can be applied to other water-stressed regions operating in environments of economic and hydrologic constraints on water use. Basin scale modeling approach provides a general framework for formulating water management policies, consistent with the principles underlying the European Union Water Framework Directive.  相似文献   
974.
Valuing climate protection through willingness to pay for biomass ethanol   总被引:3,自引:0,他引:3  
This study uses a multi-part, split-sample contingent valuation method (CVM) and fair share (FS) survey to better understand the public's valuation of mitigating global climate change through its willingness to pay for biomass or “cellulosic” ethanol. In addition to a basic CVM question, a related scenario was developed that asked half of the survey respondents to state their fair share cost to lessen a potential food shortage in the next decade, also through the expanded use of cellulosic ethanol. Three alternative biomass feedstocks were assessed: farming residues, forestry residues and paper mill wastes, and municipal solid wastes. Overall a slightly larger proportion of respondents were WTP extra for cellulosic ethanol in the basic CVM scenario than in the FS scenario, though no significant differences were found in the WTP for the different feedstocks. Bid curve lognormal regression results for the two models were similar, supporting the idea that asking a FS rather than a conventional WTP question may be justifiable in some circumstances, such as in cases of a national emergency.  相似文献   
975.
Respondent uncertainty in a contingent market for carbon offsets   总被引:1,自引:0,他引:1  
The main objective of this paper is to provide additional empirical evidence of what explains respondent uncertainty in contingent valuation (CV) and how this in turn affects stated willingness to pay (WTP). Air travelers asked to pay a carbon travel tax to offset carbon emissions from flying were asked how likely it is that they will actually pay if the tax is voluntary. When changing the market compliance imperative from a mandatory carbon tax to a voluntary contribution, a third of all air travelers consider it unlikely they will actually pay their stated WTP amount. An ordered probit estimation approach is applied to identify the sources of respondent uncertainty. Besides the bid price, respondent sense of responsibility and belief in the effectiveness of the voluntary carbon market are among the main reasons for the experienced uncertainty.  相似文献   
976.
Optimal dynamic scale and structure of a multi-pollution economy   总被引:1,自引:0,他引:1  
We analyze the optimal dynamic scale and structure of a two-sector-economy, where each sector produces one consumption good and one specific pollutant. Both pollutants accumulate at different rates to stocks which damage the natural environment. This acts as a dynamic driving force for the economy. Our analysis shows that along the optimal time path (i) the time scale of economic dynamics is mainly determined by the lifetime of pollutants, their instantaneous harmfulness and the discount rate; (ii) economic scale and structure, as well as resulting welfare, may be non-monotonic, and (iii) environmental damage may exhibit an inverted U-shape form. These results raise important questions about the optimal design of environmental policies in a multi-pollution economy. We suggest a system of dynamic Pigouvian emission taxes, each of which should be levied specifically on one particular pollutant. We show that the optimal time path of each tax level is determined by the characteristics not only of that particular pollutant but also of all other pollutants.  相似文献   
977.
The “human appropriation of net primary production” (HANPP) has been suggested as a comprehensive indicator to measure impacts of human land use on ecosystems. It accounts for (a) human-induced changes in biological productivity and (b) biomass harvest. This study presents an analysis of aboveground HANPP in the Philippines between 1910 and 2003, a period characterized by massive deforestation and increases in land use intensity and biomass extraction. Results show a steep increase of aboveground HANPP from just below 35% of potential productivity in 1910 to slightly above 60% in 1970 and constant values since then. Large-scale changes in land cover and agricultural practices were the main direct determinants of this trajectory in HANPP. Remarkably, HANPP grew at much slower pace than population did: While the amount of NPP appropriated by humans doubled throughout the period, population increased by a factor ten. Increasing efficiency in terms of biomass extraction per unit of area, relying on ever-increasing inputs, and changes in the nation's physical biomass trade balance were of major importance for this difference in growth rates. In the coming decades, the Philippines will have to face the challenge to meet increases in biomass demand without putting even higher strains on the ecosystems.  相似文献   
978.
田樱 《北方经贸》2009,(10):45-47
在过去的二十多年时间里,福建经济取得了全面的发展,对外贸易也进入了一个高速发展的阶段,成为名副其实的贸易大省。但是,我们也要清醒地认识到,福建的外贸增长主要是粗放型的增长,长期依靠劳动力成本优势扩大出口的格局没有改变,依靠低效大量消耗能源、资源出口产品的现象没有得到有效控制。出口规模虽然不断扩大,但出口效益低下,竞争力较弱。这种粗放型的增长方式与福建环境、资源约束的矛盾越来越突出,贸易条件不断恶化,贸易摩擦增多,导致了贸易的不和谐。因此,粗放型的外贸增长方式难以为继,必须转变外贸增长方式,走集约型的增长道路,这是福建省所面临的各种国内外的客观条件提出的迫切要求,也是实现对外贸易可持续发展提出的迫切要求。  相似文献   
979.
利用“社会照料”的理论,通过对永济市农村老年照料模式的个案研究,从三个维度分析了农村老年照料传统模式的特点,指出了传统模式的优势和面临的挑战。  相似文献   
980.
We explore issues of group decision making for reducing global environmental risk, with particular reference to the political dynamics surrounding international agreements on tackling climate change. Continuing political delays in deciding to reduce greenhouse gas emissions may make it necessary to resort to high risk and controversial geo-engineering solutions, such as injecting large amounts of sulfur dioxide into the stratosphere, despite the unforeseen, potentially catastrophic consequences that these entail. Advances in drama theory (dt.2) are used to analyze the prospects for agreement on reducing or stabilizing greenhouse gas emissions, following the Bali agreement of December 2007. It is concluded that Western nations and emerging economies are behaving like players in a game of “chicken”, each expecting the other to take on the main burden of emissions reduction. We judge it unlikely that either will play a full part until it is too late for emissions reduction alone to avert environmental catastrophe. At that point, parties will resort to geo-engineering “fixes”, despite the risks. However, all such forecasts are conditional on decisions made and attitudes taken by political leaders and the public. Our analysis serves to pinpoint the relevant decisions and attitudes.  相似文献   
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