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1.
There is ample evidence that distance has a strong negative effect on migration. Despite its significance in migration decisions, scholars rarely explore the migration distance effect deeper than the first level of interpretation derived from the simple neoclassical theory of migration. This study revisits the migration distance effect in the spirit of Knightian distinction between risk and uncertainty. To this end, this study attempts to construct estimates of the risk premium migrants are willing to pay to avoid the risk associated with migration distance. The results show that the magnitude of the distance effect is not rationalized by risk aversion in the Arrow–Pratt sense (Arrow, 1965, The theory of risk aversion, Yrjo Jahnssonin Saatio, Helsinki, Finland, 90; Pratt, 1964, Econometrica, 32, 122). In particular, the risk premium demanded by distant rural residents is unjustifiably higher compared with that of those living closer to urban areas in their migration decisions. The results suggest that the migration distance effect is analogous to the equity home bias puzzle and the Ellsberg paradox in that the assumption of subjective expected utility can lead to seemingly irrational human behaviors. Some of the findings in this study shed light on the role of subjective aspects such as perception, confidence, and pessimism in migration decisions, which have been neglected in the literature.  相似文献   
2.
Typhoon Aere in 2004 induced severe sedimentation and loss of storage capacity of the Shihmen Reservoir in northern Taiwan. The resulting dramatic increase in the turbidity of the water seriously affected the water supply. To effectively maintain the stability of the water supply and maintain the reservoir’s storage capacity, the government of Taiwan began to plan and construct a series of improvement measures, such as a sediment flushing tunnel, the JhongJhuang Bank-Side Reservoir, and the Amuping Desilting Tunnel. However, previous studies only focused on the impact of the sediment flushing tunnel and the Amuping Desilting Tunnel on the downstream riverbed, and did not consider the possibility of increasing sediment discharge after the completion of the JhongJhuang Bank-Side Reservoir. In addition, climate change will cause the intensity of extreme rainfall to increase enormously in the future. That rainfall and extra sediment flushing will challenge the existing flood prevention facilities. Therefore, this study considered that the JhongJhuang Bank-Side Reservoir will increase sediment discharge of the Shihmen Reservoir, and used dynamical downscaling extreme typhoon data of climate change under the RCP 8.5 scenario to explore the flood prevention and riverbed migration of the main channels of the Dahan and Tamsui Rivers in the future. We used the rainfall–runoff model of Hydrologic Modeling System to simulate rainfall and runoff, and used the hydraulic and sediment transport model of CCHE1D to holistically simulate flood events and consequent river scouring and deposition behaviors. Our results showed that the projected peak discharge during the late 21st century (2075 to 2099) will be at least 50% higher than that during the baseline (1979 to 2003) period. In terms of flood prevention, the potential of overbank flooding will increase in the downstream area, and the trend of long-term change in the riverbed will be dominated by degradation (-0.489 ± 0.743 m) in the future. The improvement measures will have a limited impact on riverbed migration (0.011 ± 0.094 m) in the Dahan and Tamsui Rivers. After the operation of the JhongJhuang Bank-Side Reservoir, the Shihmen Reservoir is expected to increase the sediment discharge ratio by 70% during floods, and it will not cause excessive water turbidity that may affect downstream water supply.  相似文献   
3.
Two of the main forces driving European emigration in the late nineteenth century were real wage gaps between sending and receiving regions and demographic booms in the low‐wage sending regions. Our new estimates of net migration for the countries of sub‐Saharan Africa show that exactly the same forces driving African across‐border migration are at work today. The results suggest that rapid growth in the cohort of potential young emigrants, population pressure on the resource base, and slow economic growth are likely to intensify the pressure for migration out of Africa and into high‐wage OECD countries over the next two decades.  相似文献   
4.
Human capital raises rural incomes, but this effect is swamped by higher returns to human capital in urban markets. This leads to "brain drain" from rural areas. Populations grow more rapidly in rural counties that have a diversified employment base. Farm population grows faster (or declines more slowly) in counties with relatively high farm income, and nonfarm populations grow faster in counties with relatively high nonfarm income. However, higher farm incomes lead to slower nonfarm population growth and vice versa. Rural county government services financed by local taxes or debt have neutral or negative effects on population growth.  相似文献   
5.
This paper investigates public and private choices between internationally applicable and country‐specific education when graduates are mobile. Human capital depends on innate skills and study effort with either type of education. It is shown that national governments provide too few students with internationally applicable education, and too many with country‐specific education. This effect is mitigated, but not entirely eliminated, by the introduction of a graduate tax, according to which graduates are required to pay part of their taxes to the country where they received their education, regardless of residence. However, private educational choices are socially optimal with suitably differentiated tuition fees.  相似文献   
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7.
农村劳动力转移模型:基于中国制度背景的构造   总被引:2,自引:0,他引:2  
本文在对经典的农村劳动力流动模型进行理论梳理的基础上,引入中国的制度变量,试图构建适合中国制度背景的农村劳动力转移模型,同时,运用经验事实对其作进一步的实证检验,并分析了模型的政策含义。  相似文献   
8.
农村剩余劳动力转移的理论、现状与政策建议   总被引:4,自引:1,他引:4  
文章在论述农村剩余劳动力转移相关理论的基础上,阐述了我国农村剩余劳动力转移的现状,并提出相关的政策建议,倡导城镇化及发展劳动密集的第三产业,为农村剩余劳动力转移提供就业岗位。  相似文献   
9.
经济增长通常意味着贫困率的下降,然而,对于增长很慢的经济体或经济增长没有带动贫困率降低的案例,这种假设似乎并不成立.中国两个较为贫困省份的数据展示了这样一个谜题:贵州省的经济增长缓慢但农村贫困率的下降较为显著,对这一现象不妨称之为"贵州新现象";与此同时,云南省经济高速增长但贫困率下降较为迟缓.根据相关考察和统计数据的分析,交通、流动人口、旅游业和矿产业四个因素是解释这个谜题的关键.这四个因素在两个省的不同分布和构造解释了它们经济增长与贫困率下降关系中的不平衡性.  相似文献   
10.
中国劳动力市场的二元分割及其就业效应   总被引:9,自引:3,他引:9  
我国的劳动力市场既有经济转型时期的非规范性,又有发展中国家二元经济和二元社会结构的特征,存在二元四级分割的情况。运用哈里斯-托达罗模型及成本-收益分析方法,可以考察我国二元四级市场上的劳动力流动状况及其就业效应。  相似文献   
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