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801.
Andrea Fosfuri 《战略管理杂志》2006,27(12):1141-1158
The licensing of technology entails a trade‐off: licensing payments net of transaction costs (revenue effect) must be balanced against the lower price–cost margin and/or reduced market share implied by increased competition (profit dissipation effect) from the licensee. We argue that the presence of multiple technology holders, which compete in the market for technology, changes such a trade‐off and triggers more aggressive licensing behavior. To test our theory, we analyze technology licensing by large chemical firms during the period 1986–96 for 107 chemical products. We find that the rate of technology licensing displays an inverted U‐shaped relationship with the number of potential technology suppliers and is negatively related to the licensor's market share and to the degree of technology‐specific product differentiation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
802.
化工机械的使用强度大,若不注意维修和保养的话很容易造成设备的耗损,缩短设备的使用寿命。下文中就主要针对化工机械的维护与管理具体探讨了几项措施,以期能够为提高机械的使用效率、促进企业发展提供一些参考。 相似文献
803.
城际物流运输跨越不同的行政区,政策差异给城际物流管理提出了挑战。航空运输一般都是跨行政区运营,结合欧盟航空碳交易案例,设计了两种碳交易政策情景,构建了跨行政区城际运输网络均衡模型,推导了相应的性质,最后给出了政策建议。 相似文献
804.
污闪是指电气设备绝缘表面附着的污秽物在潮湿条件下,其可溶物质逐渐溶于水,在绝缘表面形成一层导电膜,使绝缘子的绝缘水平大大降低,在电力场作用下出现的强烈放电现象。本文主要介绍污闪超声波检测技术及其原理,以及该项检测技术在沿海输电线路中的应用。 相似文献
805.
806.
本文通过对散化船的开式透气系统和控制式透气系统的介绍,分析了其设置的原因,引出规范中对透气系统的要求,从而提出针对散化船透气系统的检验要点,为同类船舶透气管系的安装与检验工作提供参考。 相似文献
807.
Daniel Rodriguez Roman Stephen G. Ritchie 《International Journal of Sustainable Transportation》2017,11(6):406-421
The emissions generated by motor vehicles remain a major source of air pollutants that affect public health and contribute to anthropogenic climate change. These negative externalities can be reduced, in part, with the implementation of environmentally oriented road pricing schemes, which can be designed using optimization-based approaches. In this paper, a toll design problem is proposed for determining toll locations and levels that minimize the expected human exposure to air pollutants and the related environmental inequalities, subject to constraints on pollutant concentration levels and implementation costs. The practical use of the proposed problem is hindered in most real-world applications by the computational costs associated with the evaluation of candidate solutions, as is common for network design problems. Furthermore, the problem cannot be expressed analytically given the multiple types of models (e.g., traffic assignment, emissions, air dispersion models) that would be required to evaluate a single design alternative. For these reasons, a derivative-free surrogate-based solution algorithm is proposed for mixed integer problems like the ones considered here. Numerical examples are used to illustrate possible applications of the proposed model and to test the performance of the surrogate-based algorithm. Relative to a joint simulated annealing-genetic algorithm heuristic and a genetic algorithm-based approach, the proposed algorithm found better solutions in fewer function evaluations. 相似文献
808.
Renee Rico 《Environmental and Resource Economics》1995,5(2):115-129
In 1990, the U.S. Congress passed legislation that amended the Clean Air Act to create a new program to mitigate the effects of acid deposition in the U.S. through emission reductions of sulfur dioxide (SO2) and nitrogen oxides (NOx) at electric utility plants across the country. The SO2 reductions, totalling a 40% reduction nationally from 1980 levels or a 10 million ton reduction annually, are achieved largely through an emission trading system, the largest program of its kind designed to date. This trading system has the potential to save up to half of the compliance costs associated with more traditional source-by-source emission limit programs.This paper briefly discusses background on the acid rain issue in the United States, and the principal features of the program, including: a permanent cap on utility emissions of SO2 beginning in 2010, decision to grant up-front allocation of emission credits to reduce individual approvals of trades, the use of continuous emission monitors and automatic penalties to ensure compliance, and integration of the Acid Rain program requirements with other Clean Air Act programs. The paper also discusses the development of the allowance trading market to date, including the types of compliance options chosen and quantity and type of emissions trading being conducted.The U.S. Government right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged. 相似文献
809.
Muthukumara S. Mani 《Environmental and Resource Economics》1996,7(4):391-411
This paper examines the implications for the use of trade measures as weapons to address global environmental concerns. There are already proposals in the U.S. senate to impose an environmental tariff against foreign nations whose cost advantages stem from less stringent environmental standards than the U.S. The paper argues that trade policy measures typically are not the first best instruments for achieving environmental objectives. Even theoretically they could be shown to be welfare improving only under a very narrow range of circumstances. Their use in place of more efficient policy instruments may not only end up distorting the patterns of world trade but also may worsen the overall patterns of environmental quality. Simulation exercises undertaken here suggest that it is highly unlikely that countries would alter their environmental behavior because of the imposition of the proposed U.S. tariff. Hence the proposed legislation has very uncertain environmental consequences. Even if the policy has been mainly designed to protect domestic industries, it would only provide a minor margin of protection because the costs of complying with the environmental standards represent a relatively small element in the total costs. The analysis suggests that trade policy introduced in this fashion will have no significant impact on the patterns of world trade and pollution. 相似文献
810.
In this paper we consider the dynamic behavior of a firm that is subject to environmental regulation. It is assumed that, in order to prevent firms from polluting the environment excessively, the government imposes an emissions tax. We determine how an emissions tax influences the firm's decisions concerning investments and abatement efforts. In the model we incorporate the realistic property that a given abatement expenditure leads to more pollution reduction when pollution is large. This property implies increasing returns to scale with respect to pollution reduction. It turns out that, together with the usual assumption of decreasing returns to scale with respect to production, this property leads to the occurrence of history-dependent equilibria in case the pollution tax rate is sufficiently large. It is possible to derive an explicit formula for the threshold tax rate above which these history-dependent equilibria can occur. We show that an investment grant by the government can influence the firm so as to approach the equilibrium with a higher capital stock. Finally, we compare our results with those of a related model where the firm faces a strict pollution standard rather than an emissions tax. Among other things, we show that growth is more suppressed under a tax than under a standard when the firm is small. 相似文献