全文获取类型
收费全文 | 843篇 |
免费 | 123篇 |
国内免费 | 52篇 |
专业分类
财政金融 | 35篇 |
工业经济 | 5篇 |
计划管理 | 42篇 |
经济学 | 35篇 |
综合类 | 6篇 |
运输经济 | 4篇 |
旅游经济 | 14篇 |
贸易经济 | 29篇 |
农业经济 | 110篇 |
经济概况 | 24篇 |
水利工程 | 714篇 |
出版年
2024年 | 4篇 |
2023年 | 52篇 |
2022年 | 42篇 |
2021年 | 46篇 |
2020年 | 43篇 |
2019年 | 47篇 |
2018年 | 44篇 |
2017年 | 52篇 |
2016年 | 58篇 |
2015年 | 40篇 |
2014年 | 50篇 |
2013年 | 62篇 |
2012年 | 67篇 |
2011年 | 71篇 |
2010年 | 46篇 |
2009年 | 34篇 |
2008年 | 33篇 |
2007年 | 26篇 |
2006年 | 43篇 |
2005年 | 34篇 |
2004年 | 19篇 |
2003年 | 22篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 19篇 |
1999年 | 11篇 |
1998年 | 4篇 |
1997年 | 8篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
排序方式: 共有1018条查询结果,搜索用时 281 毫秒
81.
安庆市排涝工程规划及其投资效益分析 总被引:1,自引:0,他引:1
安庆市位于长江中下游北岸,沿江地区在安庆市国民经济中占有举足轻重的地位,防洪排涝历来是沿江地区水利建设的重中之重。作为防洪减灾体系的一部分,自1999年以来,排涝工程在沿江地区取得了很大发展。通过分析安庆市排涝现状,介绍规划方法,提出建设任务,估算工程投资,分析工程效益,综合评价工程效果。计算和分析结果表明,工程不但具有明显的经济效益,还具有显著的社会效益和环境效益。 相似文献
82.
根据晋城市降水和其境内第二大河流——丹河径流量资料,分析了晋城市干旱化情况,对干旱化现实进行了印证,并采用Mann-Kendall趋势检验法检验了干旱化趋势的显著性;同时采用洪水资源率方法分析了晋城市洪水资源情况。分析结果表明,晋城市降水量呈现不显著减少趋势,存在干旱化问题,且近年来旱涝交替出现、极端天气频发;洪水是晋城市水资源的重要组成部分,结合晋城实际,提出了洪水资源化的措施。 相似文献
83.
84.
在对国内外干旱评估方法研究进行综述的基础上,指出干旱起因是降水偏少,但发展成灾,则有一个缓慢渐进过程,它不仅取决于降水、气温等气象条件,还与地形、土壤、作物等因素密切相关。考虑到旱灾的成因是多条件的,旱灾的影响和体现也是多方面的,只有结合干旱发展的各阶段,才能全面地认识和评估旱情。利用基于分布式水文模拟的干旱模型,在完整模拟干旱发生发展和结束过程的基础上,整合多种旱情指标,提出能反映干旱发展过程主要特征的旱情综合评估方法体系,并以长江上游川渝地区2006年严重干旱事件为例,开展了应用示例研究。 相似文献
85.
《Food Policy》2016
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
86.
《Journal of Economic Policy Reform》2013,16(2):142-159
This paper analyzes the impact of the guarantee provided by mutual guarantee societies (MGSs) on the risk premium that banks should charge for small- and medium-sized enterprise (SME) loans under the new Basel Capital Accords (Basel II and III). We also examine whether the foreseeable decrease in the theoretical credit risk premium would be compensated by the cost of the MGS guarantee. To do so, we develop a rating system for SMEs that uses a large sample of Spanish firms over the period from 2005 to 2009. We find that the final effect of the guarantee on the SME risk premium depends on the values taken by the credit variables of the MGS (essentially, the probability of default). 相似文献
87.
88.
刑罚轻缓化已经成为刑罚结构改革的总体趋势,通过对刑罚轻缓化的经济分析,我们可以挖掘出刑罚轻缓化背后深层次的原因,那就是"高概率的惩罚与轻刑化"的组合是预防和控制犯罪最为经济有效的方式,而轻刑化即我们所谓的刑罚轻缓化。在刑罚轻缓化的背景之下,透视罚金刑与自由刑的适用,我们可以发现罚金刑更符合刑罚轻缓化之意旨,应提升到主刑的地位,未来我国的刑罚结构改革也应以罚金刑为主导,而自由刑只起辅助的作用。 相似文献
90.
《International Review of Applied Economics》2012,26(2):205-221
This paper explores a Post Keynesian, ‘new economics’ approach to climate policy, assessing the opportunities for investment in accelerated decarbonisation of the global economy to 2020 following the Great Recession of 2008–2009. The risks associated with business-as-usual growth in greenhouse gas (GHG) concentrations in the atmosphere suggest that avoiding dangerous climate change will require that the world’s energy-economy system is transformed through switching to low-carbon technologies and lifestyles. Governments have agreed a target to hold the increase in temperatures above pre-industrial levels to at most 2°C and have offered reductions by 2020 in GHG emissions or the carbon-intensity of GDP. The effects of policies proposed to achieve pathways to 2020 towards this target are assessed using E3MG, an Energy-Environment-Economy (E3) Model at the Global level. E3MG is an annual simulation econometric model, estimated for 20 world regions over 1972–2006 adopting a new economics approach. Additional low-GHG investment of some 0.7% of GDP, with carbon pricing and other policies, is sufficient to achieve a pathway consistent with a medium chance of achieving the long-term target. GDP is above reference levels because decarbonisation reduces world oil prices and increases investment. Employment is some 0.9% above reference levels by 2020 and public finances are almost unaffected. 相似文献