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   352篇
  免费   33篇
  国内免费   1篇
财政金融   6篇
工业经济   6篇
计划管理   31篇
经济学   64篇
综合类   14篇
贸易经济   43篇
农业经济   187篇
经济概况   35篇
  2024年   1篇
  2023年   12篇
  2022年   22篇
  2021年   19篇
  2020年   16篇
  2019年   14篇
  2018年   16篇
  2017年   15篇
  2016年   21篇
  2015年   14篇
  2014年   19篇
  2013年   50篇
  2012年   26篇
  2011年   33篇
  2010年   18篇
  2009年   15篇
  2008年   16篇
  2007年   11篇
  2006年   14篇
  2005年   7篇
  2004年   6篇
  2003年   5篇
  2002年   4篇
  2001年   2篇
  2000年   4篇
  1999年   1篇
  1998年   3篇
  1997年   1篇
  1991年   1篇
排序方式: 共有386条查询结果,搜索用时 31 毫秒
21.
Using data for a long panel of 90 developed and developing countries, this article explores the effects of research and development (R&D) and fixed capital stock on agricultural land productivity over the period 1961–2012. Instruments are used for R&D to deal with feedback effects and measurement errors. The results show very high social returns to investment in R&D and to fixed capital stock, suggesting that increasing investment in these factors are promising ways of arresting the increasing food prices due to increasing demand for animal protein, population growth, desertification, salinization, soil erosion, climate change, and decreasing growth in land productivity.  相似文献   
22.
发展幼儿教育可以扩大就业市场,可以为提高劳动力素质奠定基础,同时可以推动幼儿师范教育的进一步发展。各级政府要抓好学前教育的普及工作;小学学前班的从教人员应纳入正常的编制管理;幼儿园的收费不应以园所属性定标准;可将部分小学改办成幼儿园,以避免教育资源的浪费。尤应充分发挥“省西部地区幼教师资中心”的作用,加强对现有非幼师专业的教师培训,使之专业化。  相似文献   
23.
The present paper describes the benefits and costs, in qualitative terms, of managing food price instability in Asia in the context of promoting economic growth and poverty reduction to improve food security. The experience of Asian governments in actual practice with price stabilization is discussed in the context of managing an efficient transition to market‐mediated food security. Recent experience in Indonesia, where a sharp increase in rice prices (caused by a ban on rice imports) pushed 4 million people into poverty, provides continued motivation for the analytical story in this paper.  相似文献   
24.
闫淑清 《价值工程》2010,29(4):41-41
随着农村经济结构的调整,农村劳动力分配形式随之转变,从事农业生产的劳动力逐渐减少,水稻生产规模和生产方式出现了多样化,突出表现在水稻插秧方式的变革。对插秧效果、生育进程、抗逆性及产量效益进行调查分析,以便为今后推广应用提供理论和实践依据。  相似文献   
25.
The paper jointly evaluates the determinants of switching to Jasmine rice and its productivity while allowing for production inefficiency at the level of individual producers. Model diagnostics reveal that serious selection bias exists, justifying use of a sample selection framework in stochastic frontier models. Results from the probit variety selection equation reveal that gross return (mainly powered by significantly higher Jasmine rice price), access to irrigation and education are the important determinants of choosing Jasmine rice. Results from the stochastic production frontier reveal that land, irrigation and fertilisers are the significant determinants of Jasmine rice productivity. Significantly lower productivity in Phitsanulok and Tung Gula Rong Hai provinces demonstrate the influence of biophysical and environmental factors on productivity performance. The mean level of technical efficiency is estimated at 0.63 suggesting that 59% [(100 ? 63)/63] of the productivity is lost due to technical inefficiency. Policy implications include measures to keep Jasmine rice price high, increase access to irrigation and fertiliser availability, as well as investment in education targeted to farm households which will synergistically increase adoption of Jasmine rice as well as farm productivity.  相似文献   
26.
国内外诸多研究发现,父母特质、家庭养育质量是家庭环境中影响婴儿依恋类型的重要方面,但仅考虑单一因素的影响并不能全面反映婴儿在家庭环境中的实际情况,Belsky、Hedwig等用生态学观点考察家庭环境中各因素对婴儿依恋类型形成的影响,更具实践指导意义。  相似文献   
27.
研究了以糯米和番茄为主要原料生产发酵饮料的工艺。该饮料是一种低酒度、营养丰富、口味独特的浑浊型营养保健饮料。  相似文献   
28.
结合小型面粉厂短粉路工艺改造,强调完善清理设备和辅助设备的双重作用;对小型面粉厂改造必须考虑渣磨系统与清粉系统的设置与配合作用,实现联合精选物料,为前路心磨系统最大限度提供量多质优的纯净胚乳。  相似文献   
29.
文章介绍了从米糠油加工的废弃物中分离提取含量≥98%天然阿魏酸新工艺的技术原理、主要技术指标、技术创新点、关键技术与工艺,以及用户使用效果和项目鉴定结论。  相似文献   
30.
This paper applies an option approach to search for the threshold rice price toward the sustainable paddy field management under rice price stochasticity. Rice price is assumed to follow geometric Brownian motion. The management model for paddy fields is a discrete stochastic dynamic programming model with binomial approximation for geometric Brownian motion, where a control variable is a decision to sustain or terminate paddy yield management. Our computational experiments indicate that an increase in rice price volatility could lower the threshold rice price for farmers to continue rice production. It is also shown that depending on the degree of rice price volatility, even under a lower price level than production costs, maintaining the management could become beneficial. Considering an option to terminate production could make the higher expected value of rice production than without it. Using 12 sets of time series data on voluntarily marketed rice produced in Hokkaido, Aomori, Iwate, Miyagi, Akita, Yamagata, Fukui, Ibaragi, Chiba, Niigata, Toyama and Nagano, the minimum threshold rice price of 6,700 Yen/60 kg was found in Chiba with the largest volatility, and the maximum of 7,250 Yen/60 kg in Ibaragi with the smallest volatility. If the market price becomes lower than the threshold rice price, some policy measures would be necessary toward sustainable paddy field management by covering the difference between them.  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