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1.
The well‐known index of income bipolarization proposed by Wolfson (1994) requires two groups to be split according to the median income and, therefore, to be non‐overlapping. The aim of this paper is to propose a new polarization index in the spirit of the Wolfson index. It allows for any possible partition of the population in two or more (also overlapping) groups. The new index maintains the simplicity and immediate comprehension of the Wolfson index, though being much more flexible. An application is then provided for German and Italian income data.  相似文献   
2.
I develop a model of activism and polarization in the context of electoral competition. Two candidates simultaneously announce policy platforms and seek the support of ideologically inclined activists. Activists compete to influence electoral outcomes by expending costly support for their respective candidates. The presence of activists always moderates the platform choice of candidates, compared to the case of no activism. The central finding of the paper is that the relationship between partisanship of activists and polarization is ambiguous. As activists become increasingly partisan, polarization of candidate platforms reduces or widens depending on the costs of activism. I present normative conditions under which the presence of activism and increased partisanship among activists are both welfare‐improving for voters. Finally, introducing a public funding option for candidates increases polarization in the political process.  相似文献   
3.
基于星载极化SAR数据的农作物分类识别进展评述   总被引:1,自引:0,他引:1  
[目的]农作物播种面积信息不仅可为农情监测和作物估产提供重要的数据保障,还是国家制定粮食政策和经济计划的重要依据。快速、准确地获取农作物播种面积信息能为农业生产管理提供决策支持。极化SAR不受云雨天气的影响,在农作物遥感监测方面具有巨大的应用潜力,有效利用极化SAR数据进行农作物识别研究对促进雷达技术在国家农业遥感监测和农业供给侧结构性改革中发挥更大作用具有重要意义。[方法]以星载极化SAR技术的发展过程为论述主线,从单、双极化SAR数据,单、双极化SAR数据结合光学影像,全极化SAR数据三个发展阶段,对极化SAR数据在农作物分类识别中的研究与应用进行总结,并对比分析不同的识别特征、融合算法以及分类算法的优缺点。[结果]以往研究存在以下不足:当前研究多以识别水稻为主,对于难以识别的旱地作物研究较少;目前对旱地作物识别精度不高,平均识别精度不足85%;缺乏对不同作物散射机制及其随时相变化的研究,导致分类算法机理性不足,普适性较差。[结论]在今后的研究中,旱地作物散射机制的定量确定,如何利用散射机制及其变化来提高旱地作物遥感识别精度和普适性;目前分类算法大都是基于光学影像设计,如何利用SAR特殊的成像方式优化设计适用于极化SAR数据的分类算法,得到更高的分类精度;如何更好的跟光学遥感等多源数据(光学数据、GIS数据等)结合来提高精度,将成为未来极化SAR农作物识别中三个亟需重点解决的问题。  相似文献   
4.
卫星量子通信是建立全球量子通信网络的最佳选择之一。针对采用偏振编码的卫星量子通信中的偏振保持问题,研究了大气散射和卫星与地面站间相对运动等因素对量子偏振态相位和对准的影响以及相位延迟和对准误差对系统量子误码率的影响,分析了背景噪声和系统硬件噪声对通信产生的影响以及单光子通信过程中可能受到的光子分离攻击干扰,为量子信号认知设计提供借鉴意义。  相似文献   
5.
Canada's experience during and after the financial crisis appears to distinguish it from its international peers. Canadian real estate sales and values experienced record increases since the global financial crisis emerged in 2008, rather than declines, and Canada did not witness any bank failures. The dominant trope concerning Canada's financial and housing markets is that they are sound, prudent, appropriately regulated and ‘boring but effective’. It is widely assumed that Canadian banks did not need, nor receive, a ‘bailout’, that mortgage lending standards remained high, and that the securitization of mortgages was not widespread. The truth, however, does not accord with this mainstream view. In fact, the Canadian financial and housing markets reveal marked similarities with their international peers. Canada's banks needed, and received, a substantial ‘bailout’, while federal policies before and after the financial crisis resulted in the massive growth of mortgage securitization and record household indebtedness. This article documents the growth of Canada's housing bubble, the history of mortgage securitization, and of government policies implemented before and after the crisis. Instead of making the Canadian financial and housing sectors more resilient and sustainable, the outcomes of state responses are best understood as regressively redistributive.  相似文献   
6.
收入和财富分配的不平等一直是中国改革发展中的重要问题。针对中国经济的特点,可以从政府改革的角度来研究如何更好地进行收入分配改革。地方政府主导推动地方经济的做法对收入不平等的扩大起了重要作用,加快政府职能转换,是使收入分配改革真正落到实处的破局之处,也是实现收入分配合理化可行的第一步。要改变地方政府的经济职能,降低它直接参与基础设施的程度,改革地方土地财政,建立垂直管理机构,以分散它的一部分经济管理职能,为收入分配改革打开空间。  相似文献   
7.
We provide an institutional insight into the trend of income polarization within the U.S. working class. In contrast to the previous industrial waves, the current and ongoing industrial revolution is characterized by the replacement of “creative destruction” with jobless growth. Instead of replacing the lost jobs with new ones, new disruptive technologies eliminate more jobs in traditional labor and capital-intensive sectors than create jobs in new idea-intensive sectors. By examining the relationship between the income share of the bottom 50 percent, the middle 40 percent, and the top 10 percent and technological progress, we obtain robust econometric results. According to our results, the income polarization among U.S. workers can be associated with the shift of R&D activities from the public to the corporate sector. The concentration of innovations by corporate capital limits the power of society to reduce inequality and to provide greater social stability through “the incredible productivity” of technological progress.  相似文献   
8.
This article scrutinizes the much used, but less examined, concept of ‘trickle down' in an urban setting. We make a distinction between the production of and distribution in the city, and argue that trickle down in contemporary urban policy could be regarded as the liberal link between production and distribution. Based on interviews with key figures and document analyses, we look at the transformation of the Swedish city of Malmö from an industrial to a post‐industrial city, where, during the last two decades, we have found three concurrent components: the ideology of trickle down; several urban policy programs and governmental policies to ‘make' money and resources trickle down; as well as increased economic polarization and segregation. A liberal critique of trickle down would argue that market mechanisms cannot by themselves solve distribution, and that government policies therefore are needed. We argue for the need to go beyond a liberal critique of trickle down and stress how unequal distribution is built into the unequal production of the city.  相似文献   
9.
This paper studies the effect of apprenticeship training on technology adoption and labor market polarization. A stylized model with two key features is developed: (1) apprentices are more productive due to industry-specific training, but (2) from the firm׳s perspective, when training apprentices, technological innovation is costly since training becomes obsolete. Thus, apprentices correlate with slower adoption of skill-replacing technologies, but also less employment polarization. We test this hypothesis on German regions given local variation in apprenticeship systems until 1976. The results show little computer adoption and no employment polarization related to apprentices, but similar displacement of non-apprentices by computers as in the US.  相似文献   
10.
胡容文 《价值工程》2011,30(16):27-28
本文对大型变压器绝缘测量的方法、国标对变压器绝缘的要求进行了分析,研究了某大型火电厂内不满足国标要求的变压器的结构对变压器绝缘电阻、吸收比、极化指数的影响,提出变压器的绝缘状况综合分析方法。  相似文献   
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