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21.
Nonlinear, symmetric, and asymmetric dependence characteristics in energy equity sectors matter to portfolio investors and risk managers because of the risks and diversification opportunities they entail. Specifically, nonlinear dependence dynamics between assets are harder to predict, monitor, and manage, and can make investment positions go wrong unexpectedly. In this paper, we investigate whether the dependence dynamics of US and Canadian large-capitalized energy equity portfolios are nonlinear, symmetric, or asymmetric. We draw our results by implementing a robust copula approach based on time-varying parameter copulas and vine copula methods. Both time varying parameter and vine-copula methods indicate that the Canadian energy sector portfolio is driven by nonlinear negative tail asymmetric dependence during the global financial crisis and when the full sample period is employed. On the other hand, it displays nonlinear symmetric dependence during the oil price crisis, implying the need for close monitoring and rebalancing and a more continuous assessment of long investment positions. The US energy sector portfolio is driven by positive tail asymmetric dependence, and by symmetric dependence dynamics during crisis and non-crisis periods.  相似文献   
22.
Mountain economies will have to play a central role in attaining the global pursuit of green economic growth as crucial bearers of ecosystems goods and services. However, these economies are not adequately represented in the development policy debates in spite of their fundamental importance towards global sustainable development. This study examines the inter relationships between energy consumption, output and carbon emissions in a developing mountainous economy using an augmented Vector Autoregression model. Time-series data over the period 1975–2013 is studied applying a multivariate framework using population and gross fixed capital formation as additional variables for Nepal. Testing for Granger causality between integrated variables based on asymptotic theory reveals a long-run unidirectional Granger causality running from GDP to energy consumption, and a unidirectional Granger causality running from carbon emissions to GDP. We suggest that the government of Nepal can address energy poverty by accelerating the adoption energy conservation policies such as rationing energy consumption and energy efficiency improvements to narrow the energy supply-demand gap. The opportunity to promote the uptake of decentralised off-grid renewable technologies in remote areas and the large scale development of hydropower at the national level also needs to be prioritized. Our results remain robust across different estimators and contributes to an emerging literature on the nexus relationships between energy consumption, income and carbon emissions in mountainous developing economies.  相似文献   
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24.
2019年3月,四部委公布新一轮新能源汽车补贴政策,相比2018年标准平均退坡超50%。自政策公布之后,国内新能源汽车市场环境发生巨变,新能源汽车销量增长明显放缓,部分新能源汽车及零部件企业经营困难甚至倒闭,加之以特斯拉为首的外资新能源汽车企业陆续在华设厂投产,使国内新能源汽车市场竞争加剧,下行压力增大,新能源汽车产业正式进入后补贴时代,在此背景下,需要政府部门、相关企业重新评估市场现状,制定新的新能源汽车产业发展战略和路径,推动产业持续健康地发展。  相似文献   
25.
Energy use is becoming more efficient due to technological innovations. We focused on the transportation sector in China to develop a national multisector computable general equilibrium (CGE) model for analyzing the rebound effect from an improvement of 10% in the energy efficiency. We compared the size of the energy rebound effect at both the macroeconomic and sectoral levels in different transportation modal subsectors, namely rail, road, water, and air travel. The findings showed that the magnitude of the rebound effect varies across the transportation modes. This is particularly true for the air transportation sector, which has an economy-wide rebound effect of 30.1% and an own-sector rebound effect of 74.6% because of a sharp increase in the export demand for air transport services. We also quantitatively evaluated the contribution of energy efficiency improvement in the transportation sector to China’s economic growth and carbon reductions and found a positive dividend effect on the economy as well as the environment. The modeling results suggest that improving overall transportation energy efficiency by 10% generates an economy-wide welfare gain of approximately 29 billion yuan, while 19 billion yuan are attributable to a more efficient road transportation subsector. Furthermore, to offset the effects of these mode-specific rebound effects, we simulated the effectiveness of different policies and solutions. These included economic instruments in the form of energy, environmental, and carbon taxes, household transport consumption structure adjustments, and energy structure adjustments. This study revealed that combining these sustainable development policies offers opportunities for economy-wide multisectoral improvements in energy savings, emissions reduction, and economic benefits.  相似文献   
26.
China's transport sector has been attracting great attention for its excessive energy consumption and ever-increasing pollution emissions. Thus, reducing energy intensity is one of the top priorities of China's ongoing transport upgrade. In this paper, by establishing a panel data regression model derived from the Cobb–Douglas cost function, we focus on investigating the impacts of energy price and transport productivity on transport energy intensity at the national and regional levels. The study uses the provincial panel data for 2005–2016 to perform regression analysis. The results show that: (1) energy price has a significantly negative effect on transport energy intensity in the whole China and the eastern region, whereas it has no significant impacts in the central and western China. (2) Improvements in transport productivity can effectively decrease transport energy intensity in the whole China and the three major regions. (3) Applying an extended data envelopment analysis (DEA) approach, we decompose transport productivity into four components (i.e., technical change, technology gap change, scale efficiency change, and pure efficiency change) and further differentiate their impacts in different regions. The results indicate that these four components have substantially different impacts in each region. These results provide some valuable insights for policymakers and enterprise entities aiming to adopt measures to reduce energy intensity and achieve sustainable development in China's transport sector.  相似文献   
27.
Major climate-cum-energy policies and respective impact projections rest on the widespread belief that increased energy efficiency can be equated with savings in energy use and emissions. This belief is flawed. Due to the rebound effect emissions savings from energy efficiency improvements will be generally less than what is technically feasible, or even be reversed. By means of an analytical general equilibrium model we demonstrate the latter to be true in a case that is both stark and relevant: if electricity generation is subject to a cap-and-trade scheme with partial coverage, increased efficiency of electric devices leads unambiguously to increased carbon emissions. The result implies that a proper distinction between the energy rebound and the carbon rebound is warranted, and that public policy must carefully consider the interactions between energy efficiency promotion and carbon pricing.  相似文献   
28.
This paper proposes energy consumption in the US as a new measure for the consumption capital asset pricing model. We find that (i) industrial energy growth produces reasonable values for the relative risk aversion coefficient and the implied risk-free rate; (ii) compared to alternative consumption measures, industrial energy performs well in explaining the cross-sectional variation in stock returns with the lowest implied risk aversion and pricing errors; (iii) the industrial energy consumption risk model performs equally well as the Fama–French three-factor model in the cross-sectional asset pricing tests; and (iv) total energy consumption risk is priced in the presence of the Fama–French factor risks.  相似文献   
29.
The airline and railway industry contribute immensely to economic development, however, its role in environmental pollution requires attention. Here, this study builds on the theoretical pedigree of the environmental Kuznets curve (EKC) hypothesis to explore the contribution of the air and railway transportation sector and urbanization to the emission-growth argument. We utilized annual time-frequency data from 1995 to 2014 for a panel of top 10 air passenger carrier countries using robust panel estimators that control for cross-section dependence. The empirical analysis shows a positive significant relationship between emissions and economic growth, thus, economic growth is emission-embedded with limited green growth. The existence of the EKC phenomenon is affirmed for the investigated blocs — where economic growth is prioritized over environmental quality. Additional, while air transportation drives pollution, railway transportation and urbanization decline emission over the sampled period. The results underscore the need for clean and environmentally friendly energy sources for air sector operations.  相似文献   
30.
创新作为中关村科技园区的基本属性,创新质量决定了中关村科技园区发展质量。科技园区促进区域产业集聚,集聚显著影响科技园区创新,但缺乏对“一区多园”创新质量的综合集聚效应研究。由此,建立中关村科技园区创新质量指标体系,在分析中关村科技园区3种集聚模式的基础上,建立集聚模式对创新质量影响的动态空间面板模型;以2006—2017年中关村科技园区等相关数据为基础,研究不同集聚模式与创新质量的时空效应并对其进行分解分析。结果表明,中关村科技园区创新质量呈现显著时间循环效应和空间溢出效应,各园区创新质量空间集聚存在高-高、低-低等模式并随着时间推移发生跃迁。所有园区受到正向显著的专业化集聚影响,大兴-亦庄园受到负向显著的多样化集聚影响,而房山园、密云园和延庆园受到的多样化集聚影响不显著,海淀园、朝阳园、大兴-亦庄园、东城园、西城园、通州园、门头沟园和顺义园受到市场竞争集聚效应的影响。  相似文献   
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