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   2790篇
  免费   90篇
  国内免费   111篇
财政金融   123篇
工业经济   160篇
计划管理   547篇
经济学   591篇
综合类   349篇
运输经济   16篇
旅游经济   42篇
贸易经济   385篇
农业经济   167篇
经济概况   608篇
邮电经济   3篇
  2023年   11篇
  2022年   45篇
  2021年   53篇
  2020年   45篇
  2019年   42篇
  2018年   43篇
  2017年   59篇
  2016年   59篇
  2015年   75篇
  2014年   153篇
  2013年   220篇
  2012年   227篇
  2011年   260篇
  2010年   216篇
  2009年   255篇
  2008年   307篇
  2007年   268篇
  2006年   246篇
  2005年   136篇
  2004年   93篇
  2003年   51篇
  2002年   26篇
  2001年   9篇
  2000年   53篇
  1999年   3篇
  1998年   9篇
  1997年   6篇
  1996年   4篇
  1995年   4篇
  1994年   1篇
  1993年   3篇
  1992年   1篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1985年   2篇
排序方式: 共有2991条查询结果,搜索用时 131 毫秒
1.
Cluster emergence is an important topic but weakly conceptualized in the literature. Focusing on the interaction of the local knowledge pool and firm growth, the paper develops a comprehensive framework to understand cluster emergence. In the framework, the cluster formation process starts with the collision of local and external knowledge which generates an innovation and stimulates the creation of local pioneering firms in a new field. To support the growth of follow-up entrants in the new industry, the local knowledge pool needs to be expanded and deepened through local knowledge sharing and external knowledge inflows. The enlarged local knowledge pool enables local firms to grow and explore other fields further. To promote cluster emergence, public policies need to facilitate the interaction of the local knowledge pool and firm growth. The paper illustrates the interactive framework with two aluminum extrusion clusters in China that emerged in different ways over different time periods.  相似文献   
2.
Several consumer studies have shown considerable market potential for sustainable meat products, however, their markets shares are still marginal. In Germany, the sustainable aspects “organic,” “local origin,” and “animal welfare” are of special interest. To obtain a precise overview of potential target groups for these meat categories and their choice of store format, 620 German consumers were surveyed on their attitudes toward sustainable meat production and their shopping behavior. First, target groups based on consumers’ attitudes were identified by cluster analysis, taking into account possible overlaps. Consumers were also clustered by their store format choice and their preferred type of meat packaging. A cross tabulation of the results then provided insights into which store format and type of meat packaging is preferred by the target groups for sustainable meat products. Due to overlaps found in the target groups, the existence of important subgroups was shown. Amongst the target groups, only a slight preference for unpackaged meat products was found. Basically, the offer of sustainable meat products appears of interest for all store formats, with particular emphasis on supermarkets. The results of this study can support producers and retailers developing new and tailored marketing strategies for sustainable meat products.  相似文献   
3.
以北部湾城市群为例用三维生态足迹模型、偏最小二乘法、空间计量模型分析了其自然资本利用状况、空间相关性、驱动因素。结论:(1)城市群自然资本利用处于不可持续状态;(2)自然资本利用程度划分为低、中、高三类,城市也相应分成三类;(3)自然资本利用的主要驱动因素是人口因素、社会经济;(4)空间分析显示全局莫兰指数为正,空间集聚显著,表明自然资本利用存在空间正相关;空间误差模型拟合度最好,并证明自然资本存量占用与人口总量正相关,与GDP总额负相关。  相似文献   
4.
在界定休闲渔业产业化概念的基础上,从经济、社会、产业和支撑四个方面,创新性地选取26项指标构建休闲渔业产业化发展潜力评价指标体系,采用因子分析法和层次分析法对长江经济带11个省份休闲渔业产业化发展潜力进行科学评价。结果表明,长江经济带休闲渔业产业化发展潜力呈现东部沿海地区和中部的湖北相对领先,中部其余省份和西部地区相对落后的分布格局。进一步采用聚类分析法将长江经济带休闲渔业产业化发展潜力划分为四个等级,并分析不同等级地区存在的优势和不足,据此提出促进各地休闲渔业产业化发展的建议。  相似文献   
5.
质量是引领经济发展的标杆,质量状况决定产业集群升级的基础,质量改进优化产业集群升级的路径,质量提高影响产业集群升级的方式,质量生态系统决定产业集群升级的能力。在质量变革视角下,顺德家电产业集群通过供给侧结构性改革、产业链整合和主攻智能制造升级的路径为:一是由贴牌代工向自主品牌升级;二是由整机生产向全产业链一体化转型;三是由自动化走向智能化。推动家电产业集群升级对我国促进传统产业集群升级有重要启示,通过制造业产业集群质量全面提升以促进我国产业集群全面升级,是助力我国新时代高质量发展的必然选择。  相似文献   
6.
Recent decades have witnessed the increasing adoption of personalized price promotion (PPP) at grocery stores. Despite the growing body of research debating whether PPP is more effective than untargeted price promotions, there is no literature synthesizing the relevant evidence on food products. Therefore, we conduct a systematic review to examine empirical findings on the effects of PPP targeting food products. Outcomes of 12 identified studies demonstrate larger sales and profit boosting effects of PPP than its non-personalized counterparts. Meanwhile, the results on how this approach influences consumer behavior are mixed. The effectiveness of PPP varies among different targeting strategies (e.g. reward or cross-selling) and information collection methods (e.g. using within- or across-chain data). The findings of this review have important managerial implications for the future evaluation and application of PPP as well as imply potential directions of further research on this topic.  相似文献   
7.
Many optimization-based portfolio rules fail to beat the simple 1/N rule out-of-sample because of parameter uncertainty. In this paper we suggest a grouping strategy in which we first form groups of equally weighted stocks and then optimize over the resulting groups only. This strategy aims at balancing the trade-off between the benefits from optimization and the losses from estimation risk. We rely on Monte-Carlo simulations to illustrate the performance of the strategy, and we derive the optimal group size for a simplified setup. Furthermore, we show that estimation risk also has an impact via the criterion by which the assets are sorted into groups (like the expected excess returns or betas), but does not negate the grouping approach. We relate our work to linear asset pricing models, and we conduct out of sample back-tests in order to confirm the validity of our grouping strategy empirically.  相似文献   
8.
[目的]文章选取了山西省3个具有代表性的特色农业产业集群(运城苹果、朔州羊肉、晋城大豆)进行研究,通过探索山西省特色农业产业集群发展的优势与不足,有助于提升产品竞争力和助力区域经济发展,进而达到促进农业发展、带动农民增收的目的。[方法]文章运用2005年、2010年、2015年3个时期的数据,首先基于波特的钻石模型分析了3个产业的发展情况,然后运用区位商和集中系数指标、产业效率优势指数和规模优势指数指标分别分析了3个特色农业产业集群的集中化程度和竞争力。[结果]从集中化程度来看,运城苹果产业发展进入成熟阶段,专业化程度和集中化程度近几年一直较为稳定,进一步提升空间不大;朔州羊肉产业处于大幅上升阶段,集中化程度明显,且优于专业化程度;晋城大豆产业专业化程度优势优于集中化程度优势,但二者均呈先升后降趋势。从竞争力评价角度来看,运城苹果产业已初具产业效率优势且稳定上升,规模优势稳定且变化不明显;朔州羊肉产业具有极高的产业效率优势且高位运行,规模优势稳定且处于成熟阶段;晋城大豆产业正在形成产业效率优势,规模优势近年来稍有下降。从综合比较优势来看,运城苹果产业处于成熟阶段,朔州羊肉产业具有极强的综合比较优势,晋城大豆产业受规模优势下降的影响而下降。[结论]总体来看,3个产业作为山西省的特色农业产业,其集中化程度和竞争力均较高,且具有发展优势和发展空间,区域布局合理,已经形成或正在形成特色农业产业集群,但同时也存在一定的问题。从微观层面来说,农户、企业等微观主体应该继续发挥产品的品质优势,同时努力扩大市场份额和拓展销售渠道,积极延伸产业链,加强与科研院所的合作;从宏观层面来说,应该加强政府支持和引导,减少市场风险的不确定性。  相似文献   
9.
This paper analyzes the connection between innovation activities of companies – implemented before crisis – and their performance – measured at time of crisis. The companies listed in the STAR Market Segment of the Italian Stock Exchange are analyzed. Innovation is measured through the level of investments in total tangible and intangible fixed assets in 2006–2007, while performance is captured through growth – expressed by variations of sales, total assets and employees – profitability – through ROI or ROS – and productivity – through asset turnover or sales per employee in the period 2008–2010. The variables of interest are analyzed and compared through statistical techniques and by adopting cluster analysis. In particular, a Voronoi tessellation is also implemented in a varying centroids framework. In accord with a large part of the literature, we find that the behaviour of the performance of the companies is not univocal when they innovate.  相似文献   
10.
组网是卫星、无人机等飞行器集群实现协同的基础。传统自组织组网技术针对地面随机移动场景设计,不适用于拓扑和传输根据任务变化的飞行器集群场景,为此设计了一种管理与任务分离的组网方法,将网络分为管理面和任务面两个逻辑层面,管理面负责拓扑发现、路由建立、任务规划等基础组网功能,任务面负责任务执行过程中的数据传输功能。管理面和任务面实行不同的组网策略,从而使得网络的传输性能根据管理和任务执行的不同需求进行优化,以减少协议开销及降低传输自干扰。  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