首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   5583篇
  免费   275篇
  国内免费   71篇
财政金融   278篇
工业经济   778篇
计划管理   1658篇
经济学   850篇
综合类   722篇
运输经济   31篇
旅游经济   46篇
贸易经济   707篇
农业经济   180篇
经济概况   678篇
信息产业经济   1篇
  2024年   12篇
  2023年   58篇
  2022年   63篇
  2021年   129篇
  2020年   165篇
  2019年   97篇
  2018年   113篇
  2017年   100篇
  2016年   123篇
  2015年   188篇
  2014年   412篇
  2013年   475篇
  2012年   542篇
  2011年   679篇
  2010年   589篇
  2009年   396篇
  2008年   362篇
  2007年   338篇
  2006年   356篇
  2005年   245篇
  2004年   148篇
  2003年   106篇
  2002年   56篇
  2001年   50篇
  2000年   39篇
  1999年   18篇
  1998年   15篇
  1997年   14篇
  1996年   7篇
  1995年   10篇
  1994年   6篇
  1993年   2篇
  1992年   3篇
  1991年   2篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   1篇
  1986年   2篇
  1983年   2篇
  1982年   1篇
排序方式: 共有5929条查询结果,搜索用时 296 毫秒
131.
随着工作面功率的加大,矿井电压过低造成设备启动困难或不启动现象,甚至造成欠电压跳闸,因此1140V电压等级升高到3300V将是煤矿发展的前进方向。  相似文献   
132.
汪锋  吴俊 《技术经济》2016,(12):90-96
将电力生产作为先行于其他社会生产的生产环节,在考虑规模越来越大的电力跨省交易和非期望产出(二氧化碳排放、工业废气总排放量、工业废水总排放量等)的基础上,使用非参数网络数据包络分析模型测算了2000—2012年中国省域能源环境效率。结果表明:与考虑电力生产和跨省交易的网络DEA模型相比,利用传统DEA方法会高估电力输入省的能源环境效率、低估电力输出省的能源环境效率。指出调整电力生产布局和跨省输送网络可以有效提高地区的能源环境效率。  相似文献   
133.
This study uses a system-of-equations approach to model the substitution relationship between Australian domestic and outbound tourism demand. A new price variable based on relative ratios of purchasing power parity index is developed for the substitution analysis. Short-run demand elasticities are calculated based on the estimated error correction almost ideal demand systems. The empirical results reveal significant substitution relationships between Australian domestic tourism and outbound travel to Asia, the UK and the US. This study provides scientific support for necessary policy considerations to promote domestic tourism further.  相似文献   
134.
当下中国的城镇化是"政府主导"的城镇化,鲜有程序规制及公众参与,存在着权力裸奔的危险,城镇化推进成果难以获得正当性证成。因此,必须要完善程序机制,扩大公众参与,实现从"官控"到"民动"的推进模式转变。  相似文献   
135.
Despite the widespread belief that technology shocks are the main source of business fluctuations, recent empirical studies indicate that in the absence of financial frictions, a shock to the marginal efficiency of investment is the main source and is closely related to financial conditions for investment. We incorporate a financial accelerator mechanism and two types of financial shocks to the external finance premium and net worth in a dynamic stochastic general equilibrium model with shocks to the marginal efficiency of investment, the investment-good price markup, and the rates of neutral and investment-specific technological changes. This model is estimated using eleven US time series that include data on loan, net worth, the loan rate, and the relative price of investment. Our estimation results show that the (non-stationary) neutral and investment-specific technology shocks primarily drive output and investment fluctuations, while the external finance premium shock plays an important role for investment fluctuations. This financial shock induced substantial falls and subsequent sharp hikes in the external finance premium and caused boom–bust cycles over the past two decades.  相似文献   
136.
Research on spatial segregation has suggested that social mix may be a temporary phase in class displacement, where relations between different groups are at best divided or ‘tectonic’, for instance in England. Political and policy discourses, by contrast, tend to uncritically valorize social mix as a means to breaking up concentrations of poverty and providing neighbourhoods with a middle‐class voice. In the literature, little attention has been paid to power dynamics in socially mixed neighbourhoods and the implications this may have for understanding theory and policy. The five articles that make up this symposium address the ways in which social and ethnic groups interact in major cities in Europe and North America and, as the title suggests, this involves taking into account power relations, domination and negotiation between the different groups. There is a need to connect the experience of the deployment of power within neighbourhoods (and between them) with the discussions of power mechanisms at work in wider urban processes.  相似文献   
137.
Suppose legislators represent districts of varying population, and their assembly's voting rule is intended to implement the principle of one person, one vote. How should legislators' voting weights appropriately reflect these population differences? An analysis requires an understanding of the relationship between voting weight and some measure of the influence that each legislator has over collective decisions. We provide three new characterizations of weighted voting that embody this relationship. Each is based on the intuition that winning coalitions should be close to one another. The locally minimal and tightly packed characterizations use a weighted Hamming metric. Ellipsoidal separability employs the Euclidean metric: a separating hyper-ellipsoid contains all winning coalitions, and omits losing ones. The ellipsoid's proportions, and the Hamming weights, reflect the ratio of voting weight to influence, measured as Penrose–Banzhaf voting power. In particular, the spherically separable rules are those for which voting powers can serve as voting weights.  相似文献   
138.
The paper tests the validity of the Balassa-Samuelson hypothesis (BSH) using the within-effects and the dynamic panel generalised methods of moment (GMM) techniques for a panel of eight middle-income African countries over the period 1960–2009. We selected these countries because they exhibited a mixture of relative productivity growth and real exchange rate misalignment that fits the characterization of the BSH well. The results strongly support the BSH for this group of countries. The results are valid even after we controlled for potentially omitted variables and endogeneity. The implication is that as these countries become more productive, their currencies appreciate in real terms.  相似文献   
139.
In the oligopsony market, farmers may receive low prices and policy analysis assuming perfect competition can yield serious bias results. In this paper, we estimate oligopsony power between processors and farmers and evaluate the welfare impact of the paddy pledging program (PPP), a generous price support program in the Thai Jasmine rice market, with an imperfect competition model. We develop a model that consists of rice supply equation and derived demand equation. We then simultaneously estimate these equations using system estimation methods to recover oligopsony power parameters. Finally, we use these parameters to assess the welfare impact of the price support program. Using annual panel data running from crop marketing year 2001/2002–2015/2016 and exploiting the institutional feature of the PPP, we find strong evidence of some oligopsony power, a moderate level of oligopsony price distortion, and a negative relationship between price support and oligopsony power. We also find that the PPP is inefficient but effective in income redistribution. Moreover, the program benefits both farmers and consumers. With better policymaking decisions, the PPP can be efficient by setting a suitable support price. Therefore, our results show that in the case of the Thai Jasmine rice market, the generally accepted “wisdom” about agricultural price support policy does not necessarily hold, and price support can be designed to improve the efficiency of the market.  相似文献   
140.
While the energy generation system is changing towards the use of more renewable energies, the problem of how to deal with fluctuating energy supply is increasing. Smart appliances in households are often referenced as one possible solution, as their operation may be shifted in time and, thus, used to balance an unstable energy supply. The potential of such appliances has been studied to date mainly in pilot installations with a very limited number of participants or by making assumptions on what might be possible. With this work, a semi‐representative approach for 12 European countries was used to assess actual consumer habits for the use of washing machines and dishwashers which then could be used to calculate average load profiles for those appliances depending on the time of the day. Using these profiles, it is strait forward to calculate how much load may be shifted by those appliances in a demand response application. This allows aggregators or energy utilities to assign clear financial benefits to the shifting potential of those appliances. Consumers use the shifting of appliance operation already today for various reasons. Investigating these reasons allows to learn already a lot about the flexibility of consumers.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号