全文获取类型
收费全文 | 3103篇 |
免费 | 80篇 |
国内免费 | 41篇 |
专业分类
财政金融 | 62篇 |
工业经济 | 48篇 |
计划管理 | 222篇 |
经济学 | 653篇 |
综合类 | 446篇 |
运输经济 | 2篇 |
旅游经济 | 11篇 |
贸易经济 | 212篇 |
农业经济 | 1108篇 |
经济概况 | 460篇 |
出版年
2024年 | 10篇 |
2023年 | 56篇 |
2022年 | 44篇 |
2021年 | 68篇 |
2020年 | 120篇 |
2019年 | 78篇 |
2018年 | 86篇 |
2017年 | 102篇 |
2016年 | 131篇 |
2015年 | 55篇 |
2014年 | 139篇 |
2013年 | 205篇 |
2012年 | 195篇 |
2011年 | 248篇 |
2010年 | 203篇 |
2009年 | 245篇 |
2008年 | 267篇 |
2007年 | 197篇 |
2006年 | 216篇 |
2005年 | 150篇 |
2004年 | 98篇 |
2003年 | 78篇 |
2002年 | 48篇 |
2001年 | 61篇 |
2000年 | 47篇 |
1999年 | 28篇 |
1998年 | 8篇 |
1997年 | 13篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有3224条查询结果,搜索用时 17 毫秒
941.
现代农业示范园区的发展与思考 总被引:4,自引:0,他引:4
现代农业示范园区是农业科技创新中涌现出来的科技与产业相融合的新型组织形式,它以技术密集为特征,以科技开发、示范、辐射和推广为主要功能,对于推动传统农业转型、促进区域农业结构调整和涉农产业升级、增强农业和农产品国际竞争力具有重要的现实意义和深远的战略意义。本文通过分析现代农业示范园区建设成效和建设中的问题,提出加快现代农业示范园区的政策建议。 相似文献
942.
943.
资源型经济影响下的现代农业发展 总被引:2,自引:1,他引:1
本文从资源型经济和现代农业发展两者相结合角度出发,研究资源型经济影响下农民和煤矿资源开发者发展意图的差别所造成的农民发展现代农业的行为和煤矿资源开发者行为的冲突,矿产资源开发者选择破坏资源环境行为发展路径和农民选择保护资源环境行为发展路径。这两种发展路径决定着只有建立煤矿资源开发者和农民良性互动发展机制才能保证资源型经济影响下现代农业的发展。 相似文献
944.
随着工业化、城镇化的深入发展,我国农业发展面临资源环境的双重约束.解决我国农业资源环境双重约束的根本出路在于走资源节约型、环境友好型农业(即“两型农业”)之路.以湖南省332个农户为研究对象,通过问卷调查考察农户自为从事两型农业生产的行为.调查显示,当前农户对发展两型农业的行为态度给予负面评价,在主观规范上缺少一定的压力以及感知行为控制能力低下,从而导致农户自为发展两型农业的意向低下. 相似文献
945.
In the last decade special attention has been focused on estimating a firm’s efficiency and productivity; Stochastic Frontier Analysis (SFA) has been one of the most used techniques that allows the separation of inefficiency from stochastic noise, assuming homogeneous technology is available to all producers and that there is independence between observations. However, this second assumption is violated data are spatial auto-correlated, thus biasing statistical inference. Attention has, therefore, shifted to models that allow the controlling of heterogeneity introducing, in the model or in the error term, contextual variables correlated with inefficiency. In our paper we propose viewing the spatial external factors (natural or artificial) in a new way: instead of identifying ex-ante a multitude of determinants, often statistically and economically difficult to detect, we suggested using an original methodology that, following a classical SFA approach, splits efficiency into three components: the first one is linked to the spatial lag, the second one to the DMU’s specificities, and the third to the error term. Finally, we tested our method using simulated data and examined the Italian wine sector, testing the ability to control spatial, global and local heterogeneity. 相似文献
946.
Charles Weiss William B. Bonvillian 《Technology Analysis & Strategic Management》2013,25(10):1189-1208
The US national innovation system has a dual structure: part suited to rapid innovation, and part stubbornly resistant to change. The complex, established ‘Legacy sectors’ that resist change, particularly disruptive innovation, share common features that obstruct the market launch of innovations, over and above the ‘valley of death’ and other obstacles that have been the traditional focus of innovation policy. Innovations in Legacy sectors must penetrate a well-established and well-defended technological/economic/political/social paradigm that favours existing technology, characterised by (1) ‘perverse’ subsidies and price structures that create a mismatch between the incentives of producers and broader social goals, such as environmental sustainability, public health and safety, and geopolitical security; (2) established infrastructure and institutional architecture that imposes regulatory hurdles or other disadvantages to new entrants (3) market imperfections beyond those faced by other innovations: network economies, lumpiness, economies of scale, split incentives, needs for collective action, and transaction costs (4) politically powerful vested interests, reinforced by public support, that defend the paradigm and resist innovations that threaten their business models (5) public habits and expectations attuned to existing technology and (6) an established knowledge and human resources structure adapted to its needs. Beyond these obstacles, more socially desirable technologies that are driven by environmental or other non-market considerations must overcome the lack of agreed replacement standards against which putative alternatives can be judged. We have developed a new, integrative analytic framework for categorising the obstacles to market launch faced by Legacy sectors, and earlier applied this method to energy, health delivery, the long-distance electric grid, building, and air transport. In energy especially, the requirement for innovation is sufficiently urgent that large-scale domestic and collaborative international research should take place even at the cost of possible competitive disadvantage and even if it is some time before the USA adopts carbon charges and thereby puts pressure on the prevailing paradigm of fossil fuel use. We now extend this method to sustainable agriculture. American paradigms in agriculture and in energy are exported worldwide, delaying the development and spread of needed innovations that are not consistent with them. Foreign manufacturers wishing to enter US markets must suit their products in these sectors to American paradigms, while American exports of technology may be insufficiently cost conscious or respectful of environmental sustainability. Developing countries are technology takers and suffer from asymmetric innovative capability. They need to choose sources of technology best suited to their situation. India and China constitute new competitive threats, but also represent ‘innovative developing countries’ that have large domestic markets in which they are launching innovations aimed at their lower income populations. 相似文献
947.
在今后一定时期,发展现代化大农业是黑龙江省农业和农村经济发展的主题和战略任务。现代化大农业首先是现代农业,其次是具有“大”字特征的现代农业,其中“大规模”是发展现代化大农业的物质基础,“大组织”是其经营主体,“大农机”是生产工具,“大科技”是生产手段,“大服务”是保障体系,“大市场”是支撑条件,“大产业”是实现形式和发展理念,“大产出”是发展目标和必然结果。 相似文献
948.
949.
The East Usambaras in Tanzania are a tropical biodiversity hotspot where current agricultural management practices pose threats to forest conservation and development objectives. Promoting sustainable agricultural intensification (SAI) would improve long-term productivity and reduce pressure on forest reserves. The study objective was to identify household-level characteristics that influence adoption of improved management practices, specifically soil replenishment practices, in order to identify opportunities and constraints to scaling up SAI to landscape level. First, three common farming systems and a fourth agroforestry (AF) model were developed to estimate the relative profitability of incorporating fallow, manure, and non-timber forest product activities. Next, household surveys were conducted and a logistic regression analysis was used to measure the influence of socioeconomic characteristics, physical and financial assets, tenure security, and plot-specific attributes on adoption of soil replenishment practices that were specified in the model. Findings showed that the AF model was financially competitive but raises opportunity costs to labour when compared to common systems. Marital status, household size, remittances, credit access, and tenure security significantly influenced adoption of fallow and applying organic inputs. Significant plot-specific attributes included perceived fertility and distance from the homestead. Policies to scale up SAI should consider these factors and emphasize improving markets for AF species and extension services. 相似文献
950.
Today, less than 3% of the 250,000 plant varieties available to agriculture are in use. Sources of (agricultural) biodiversity are under threat and disappearing in many regions. Increasing industrialisation of agriculture and top-down agricultural research have contributed to this dependence on a relatively few plant varieties. This article argues that new approaches to agricultural development research are needed to conserve agricultural diversity, improve crops, and produce food of quality for all. Such an approach should enable small farmers on marginal lands to participate as equal partners alongside agricultural scientists, fairly sharing their know-how, expertise and seeds. Three case studies illustrate how farmers and plant breeders are working together in a diversity of agro-ecological, socio-economic and political contexts to put these new approaches into practice. New forms of collaboration are producing an increase in diversity and a number of promising improved varieties in terms of yields, agronomic traits and taste. These varieties are showing better adaptation to the local environmental conditions without requiring extra external inputs. Long-term success requires that these efforts be backed up by supportive policies, by actions to ensure that policies are implemented, and where necessary by related legislation. 相似文献