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81.
We investigate the effect of energy commodity price movements on market and electricity index returns in Turkey for the periods before, during, and after the year 2008. Although the Turkish economy is highly reliant on oil, we find that oil price does not lead either electricity or market indexes. This might be attributable to sluggish integration of financial markets in Turkey compared to developed markets. Natural gas price leads electricity index in the pre-2008 period. Its significance is reduced following the decline in natural gas usage in electricity production. This suggests that commodity dependence may be driving the link between commodity and asset prices in related sectors.  相似文献   
82.
To meet the 2 °C climate target, deep cuts in greenhouse gas (GHG) emissions will be required for carbon dioxide from fossil fuels but, most likely, also for methane and nitrous oxide from agriculture and other sources. However, relatively little is known about the GHG mitigation potential in agriculture, in particular with respect to the combined effects of technological advancements and dietary changes. Here, we estimate the extent to which changes in technology and demand can reduce Swedish food-related GHG emissions necessary for meeting EU climate targets. This analysis is based on a detailed representation of the food and agriculture system, using 30 different food items.We find that food-related methane and nitrous oxide emissions can be reduced enough to meet the EU 2050 climate targets. Technologically, agriculture can improve in productivity and through implementation of specific mitigation measures. Under optimistic assumptions, these developments could cut current food-related methane and nitrous oxide emissions by nearly 50%. However, also dietary changes will almost certainly be necessary. Large reductions, by 50% or more, in ruminant meat (beef and mutton) consumption are, most likely, unavoidable if the EU targets are to be met. In contrast, continued high per-capita consumption of pork and poultry meat or dairy products might be accommodated within the climate targets. High dairy consumption, however, is only compatible with the targets if there are substantial advances in technology. Reducing food waste plays a minor role for meeting the climate targets, lowering emissions only by an additional 1–3%.  相似文献   
83.
Oil and natural gas reservoirs typically span multiple productive leases so that no owner has rights to the entire stock of resource, resulting in production externalities. Previous literature has examined the effectiveness of government regulation in Texas and Oklahoma in abating these externalities, finding Oklahoma to be more successful in unifying common pools and securing property rights. Using regression discontinuity design, we quantify the impact of regulatory difference between the two states. We find that Oklahoma produces an average of 3361 more barrels of oil over the life of a well, relative to Texas. Given the maturity of the fields in question, the result underscores the continuing importance of addressing common pool externalities even after the primary phase of recovery has largely been completed.  相似文献   
84.
介绍了项目质量成本的概念及内涵,分析了质量和成本之间的辩证关系,总结了消减质量成本的7项措施,并提出了质量改进成本投入与收益平衡分析的建议。实践证明,通过增加预防与改进成本,可提高项目施工质量,有效降低鉴定成本和非一致性成本,最终降低项目总的质量成本,大幅度提高项目经济效益。  相似文献   
85.
Is Indonesia using the most effective possible strategies to derive revenue from its mineral resources? Auctions and work program bidding are the main ways of allocating mineral leases. In addition to the company taxes applied to all companies, governments can raise revenue from minerals owned by the state through auctions, royalties and rent taxes paid by private firms, and through dividends from state-owned firms. Indonesia uses work program bidding to allocate leases, and its production-sharing contracts are roughly equivalent to a rent tax at a high rate. This paper considers these options for raising revenues from mineral resources. It argues that efficiency and government revenue would both be increased if Indonesia relaxed direct controls on the operations of mining companies, and allocated leases by means of auctions, combined with a much lower rate of rent tax or, better still, a royalty.  相似文献   
86.
本文分析了南苏丹独立后中石油与苏丹油气合作面临的机遇、挑战及现状,针对合作中存在的问题提出中石油应通过结构性安排规避政治风险、提高项目管理能力、培养国际化人才、实施本土化策略等对策。  相似文献   
87.
李建勋 《价值工程》2011,30(12):31-31
由于焦炉集气管设备制作和安装过程中易发生挠曲变形的情况,从而影响安装的质量。通过对焦炉集气管的充分研究,可以通过集气管内衬材料、压力控制、模糊控制方法等减少绕曲变形,有效实现焦炉集气管压力稳定、平衡、长期的控制,从而提高了安装的质量。  相似文献   
88.
文章通过对锅炉煤气系统和锅炉煤气燃烧情况进行实验分析论证得出结论:采用降低煤气系统和煤气燃烧器阻损的方法,能提高锅炉燃用煤气量,改进效果良好。  相似文献   
89.
论述了以"五精四细"为模式的精细化管理在渤海石油装备华油钢管公司内的构建和实施。详细阐述了"五精四细"的基本内涵,即五精之精化、五精之精髓、五精之精品、五精之精通、五精之精密、四细之细分、四细之细密、四细之细化、四细之细则。通过实施精细化管理,企业管理水平得到全方位提升  相似文献   
90.
Abstract

Touring holidays are greenhouse gas intensive, and ways are being sought to reduce these emissions in New Zealand. This research seeks to influence rental vehicle tourists' planning and decision making towards shorter travel. Semi-structured interviews (n = 96) were conducted as part of a quasi-experimental approach, in which tourists were “treated” by receiving a purpose-designed tourist map. Three levels of planning and decision making could be distinguished, whereby both cognitive and affective processes were important. The tourist map did not influence tourists' itineraries, but tourists in New Zealand consistently followed a “travel budget” of about 3-5 hours driving per day.  相似文献   
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