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121.
Demand projections for civil aviation have forecast increases in operations in future decades. Increases in demand are beneficial to the growth and advancement of the aviation industry, but also come with the threat of significant increase in environmental impacts. In response, the industry is focusing on programs to develop technologies for reductions in fuel burn, NOx emissions, and noise. While aircraft-level impacts are an obvious metric of success, it is difficult to make informed robust technology investment decisions with respect to noise without understanding the fleet-level impacts. Fleet-level predictions of noise for technology explorations are especially complicated because it is computationally expensive, highly combinatorial, and airport-specific. Recently, rapid automated airport noise models have been developed, which can be simulated using Design of Experiments (DOE). The results of these simulations are used to generate surrogate models for airport noise contour area, which can be summed to yield a fleet-level impact. These models make use of simplifying assumptions to provide estimates of airport-level noise that are substantially cheaper to compute. They can be used to perform parametric trade-off analyses in conjunction with the equivalency assumption. Equivalency asserts that environmental impacts of a technology infused aircraft can be represented by scaled operations of the baseline aircraft in the same class. This simple assumption allows for the modeling of technology and market penetration factors under the same units: operations. This research uses surrogate models in conjunction with the equivalency assumption to examine two potential technology scenarios in a target forecast year, simulating technology and market performance factors to identify vehicle classes that could have the greatest impact in reducing contour area. Results show that technology and market performance of future notional Small Single Aisle and Large Single Aisle vehicle aircraft have the highest positive correlations with potential reductions in contour area.  相似文献   
122.
Applying econometric techniques to EU28 panel data and controlling for explanatory variables such as road types, we find that increased truck load capacity does not necessarily aggravate road traffic safety. Specifically, heavy trucks do not seem to be linked with greater numbers of traffic fatalities/accidents, medium trucks appear to be the worst performers in terms of fatalities, and light trucks seem to be the worst for accidents. In summary, our results clarify the complex relationship between truck load capacity and road safety, pointing to the existence of a negative correlation for accidents per capita and an inverse U-shaped curve for fatalities per capita.  相似文献   
123.
This article analyzes the relationship between policy instruments and technology diffusion in a North-South duopoly within an inter-temporal model. The North benefits from a monopoly period with a new technology. At the end, there is then technology diffusion from the North to the South. The Northern firm files a patent in order to slow down the diffusion. This article studies the impact of several policy instruments. The results show that the Northern government’s policy instruments slow down technology diffusion, except for an import quota. The Southern government’s policy instruments accelerate the new technology diffusion.  相似文献   
124.
The aim of this paper is to analyze the implementation level of International Public Sector Accounting Standards (IPSAS) in the member states of the European Union (EU). After an introduction of the legislative framework in the EU and a review of the literature about the implementation of IPSAS in the EU member states, this paper classifies, on the basis of a survey, the states according to their formal implementation levels of IPSAS. It also analyzes the types of accounting (cash basis accounting, modified cash basis accotmting, accrual accounting, and modified accrual basis accounting) used by the states studied. The survey shows that there are important disparities among the member states, both for the application of IPSAS and for the type of accounting that is used. Furthermore, it appears that even if IPSAS is not legally adopted in most European member states, there is a tendency to use modern accounting systems based on accrual accounting close to IPSAS.  相似文献   
125.
Both the OECD and the WTO have accumulated systematic data on the magnitude of support going to farmers as a result of farm policies. The datasets are collected for different purposes, but both give a detailed picture of the evolution of these policies. This paper extends recent work on the compatibility or otherwise of the two attempts at policy monitoring by considering the categorization of individual policy instruments in Norway, Switzerland, the US, and the EU. The results show how the OECD dataset, particularly with respect to the link between direct payments and production requirements, complements that of the WTO. Many payments classified in the WTO Green Box require production, raising the possibility that they may distort production and trade. Though the issue of correct notifications to the WTO is the province of lawyers, the implications for modeling and policy analysis are of interest to economists, and the broader question of improving the consistency of the two datasets is of importance in the quest for transparency in the interpretation of changes in farm policies.  相似文献   
126.
This research aims to validate a structural equation modeling (SEM) model for measuring warehouse performance using data from an international company in Australia (company G). Moreover, a methodological triangulation method was also adopted to test whether different methodological approaches produce convergent findings about warehouse performance measurement (WPM). These three different methods are the SEM model, the multiple case research study, and validation of the SEM model using data from 80 companies in Thailand and a company in Australia. With the results from the triangulation method, it is obvious that the SEM model can be used to measure the performance of warehouses in Thailand and Australia. Since the SEM model consists only of significant indicators, it is more appropriate than company G's scorecard. Furthermore, the SEM model can overcome the limitations of traditional models by allowing companies to compare their performance over time.  相似文献   
127.
During the European financial crisis, the European Central Bank implemented a series of unconventional monetary policy measures. We argue that these programs lowered the bond yield spreads of Euro-area countries. This hypothesis is tested using pooled OLS estimations and two different datasets: monetary policy event dummies and the purchase volumes of the Securities Markets Programme (SMP). Overall, we find significantly negative effects on bond yield spreads for both datasets, leading us to accept the hypothesis. While the OMT reduces the spreads of both crisis and non-crisis countries, LTROs and the lowering of the deposit rate to 0 percent are mainly effective in non-crisis countries. The SMP lowers the spreads of crisis countries, but it has the opposite effect on non-crisis countries. This converse effect is explained by the risk that increasingly accumulates on the ECB’s balance sheet through the SMP and that way constitutes a fiscal risk for non-crisis countries. The results are confirmed by pooled OLS estimations that measure the effect of unconventional monetary policy on central government debt.  相似文献   
128.
随着南海问题日趋复杂化和国际化,视南海地区为“海上生命线”的日本逐渐从不介入南海问题到积极插手南海事务.南海问题本是中国的内政问题,日本插手南海问题是粗暴干涉中国内政,对于中日两国的关系会带来一系列的不利影响.  相似文献   
129.
潘骞 《新疆财经》2010,(5):78-81
贴现模型是企业价值评估中应用较为普遍的模型,但在我国实践中使用贴现模型存在很多问题。本文利用自由现金流量贴现法、调整现值法、经济利润贴现法三种常用的方法,探讨贴现模型不同参数指标的原理、使用原则、使用条件及在我国实践中的适应性,希望讨论能够为企业价值评估实务提供指导和帮助。  相似文献   
130.
From July to December 2011, the three-month EURIBOR-OIS and EURIBOR-Repo spreads quadrupled and reached 100 basis points due to a stabilization of the EURIBOR and a decrease in the overnight index swap (OIS) and Repo. Using a specific monetary policy announcements and financial indicators database, we find that the European Central Bank’s (ECB’s) unconventional measures did not systematically have a calming effect: Asset buyout announcements decreased market strains, whereas interest rates and liquidity provision announcements did not. Moreover, liquidity provision seems to have a stressing effect. Our findings are consistent with the theoretical underpinnings according to which forward guidance crucially determines the effectiveness of unconventional monetary policies.  相似文献   
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