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In the U.S., virtually no new coal-fired power plants have been built in recent years. Both industry experts and academics seem to believe that no rational firm will build a new coal-fired plant. Will such a trend continue in the future? To provide insights into this question, we investigate the optimal decision of an electricity company with an irreversible and deferrable opportunity to build either a new coal-fired or natural gas-fired power plant as its new base-load resource. According to our real option analysis, the optimal decision depends on the location. In the case of the eastern U.S., it is optimal to choose a natural gas plant if a firm is given a choice among a new natural gas plant, a new coal plant and deferring the investment. However, contrary to the common sentiment in the industry and academia, building a new coal plant in the western U.S. is still more economical than building a new natural gas plant in the absence of emission pricing. Furthermore, introducing carbon pricing to western U.S. states, as California did, can substantially increase the probability that a firm will optimally choose a natural gas plant over a coal plant. 相似文献
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Radovan Kastratovi 《The Australian journal of agricultural and resource economics》2019,63(3):620-642
This research analyses the impact of foreign direct investment on greenhouse gas emissions in the agriculture sector of developing countries. Panel data from 63 developing countries for the period 2005 to 2014 was used to estimate a dynamic econometric model by applying a system‐generalised method of moments. The empirical results indicate a positive impact of foreign direct investment in agriculture on the carbon dioxide equivalent emission intensity in developing countries. The results provide weak support for the pollution havens hypothesis and imply the importance of coordination between foreign direct investment and environmental policies. 相似文献
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在处理全球卫星导航系统(Global Navigation Satellite System,GNSS)卫星信号时,针对模数转换器(Analog-to-Digital Converter,ADC)量化位数不同导致输出的信号信噪比下降的问题,推导了阵列天线波束形成后输出信号的信噪比理论计算模型,分析了ADC量化位数对阵列天线抗干扰GNSS接收机的性能影响。在7阵元天线且ADC量化位数为10的条件下,理论模型分析和数据仿真结果表明最大抗干扰能力约为85 dB。通过确定ADC量化位数与抗干扰GNSS接收机抗干扰能力之间的关系,其结论为工程应用中抗干扰GNSS接收机的ADC选型和设计提供了理论依据。 相似文献
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伴随着供应链管理的应用与发展,越来越多的企业认识到必须充分利用内外资源保持自身的竞争实力。作为重要的外部资源,供应商管理关系到企业成本与收益的平衡,而要做好供应端的成本管理首先要做好供应商的选择和优化。针对CS公司的供应商管理现状及存在的问题,探索适应企业的可操作性强的对策,以期为我国大型油气企业的供应商管理实践提供一定的参考。 相似文献
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本研究设计了一种结合二氧化碳传感器、PM2.5粉尘传感器、TVOC传感器来实现智能更新长途客车封闭空间内污浊空气的长途客车车载新风系统。本系统由各项传感器实时采集车厢内CO2、PM2.5、TVOC等数据上传至单片机,单片机判断各项数据是否超过设定阈值,若超过设定阈值,新风系统自动工作改变进、排风量;反之,新风系统不工作,实现智能控制。实验证明,本系统具有明显地改善长途客车内空气质量的效果,能够更好地保护人体健康。 相似文献
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民用气瓶也就是我们常说的液化气瓶,属于移动式高危产品,在人们日常生活中是必不可少的东西,因监管不完善导致每年发生的民用气瓶爆炸事件次数呈上升的状态,气瓶成了埋伏在我们周围的一个隐形“杀手”,严重威胁到人们的生命及财产安全,所以液化气市场需及时采取有效监管方案,彻底消除气瓶所带来的安全隐患。 相似文献
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ABSTRACTThe 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
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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