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   2815篇
  免费   198篇
  国内免费   41篇
财政金融   153篇
工业经济   106篇
计划管理   705篇
经济学   734篇
综合类   299篇
运输经济   28篇
旅游经济   60篇
贸易经济   350篇
农业经济   352篇
经济概况   267篇
  2024年   28篇
  2023年   72篇
  2022年   97篇
  2021年   96篇
  2020年   167篇
  2019年   126篇
  2018年   100篇
  2017年   87篇
  2016年   82篇
  2015年   95篇
  2014年   184篇
  2013年   260篇
  2012年   227篇
  2011年   270篇
  2010年   168篇
  2009年   159篇
  2008年   170篇
  2007年   133篇
  2006年   116篇
  2005年   99篇
  2004年   56篇
  2003年   58篇
  2002年   35篇
  2001年   29篇
  2000年   17篇
  1999年   17篇
  1998年   21篇
  1997年   17篇
  1996年   19篇
  1995年   12篇
  1994年   6篇
  1993年   4篇
  1992年   3篇
  1991年   4篇
  1990年   1篇
  1989年   3篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1984年   2篇
  1983年   1篇
  1982年   8篇
排序方式: 共有3054条查询结果,搜索用时 15 毫秒
81.
The concepts of technology convergence or technology fusion describe the phenomenon of technology overlap. Despite evidence of the higher value associated to interdisciplinary research and cross-industry innovation, few studies have investigated the characteristics of technology fusion based on patent data. This study identifies new cases of convergence relying on the International Patent Classification (IPC) of patents filed at the European Patent Office between 1991 and 2007: the first occurrence of a patent incorporating a combination of IPC subclasses signals a new instance of fusion. Duration models are employed to investigate the impact of field level characteristics derived from patent bibliometrics on the likelihood of identifying a new fusion. The results show that merges are more frequent if the focal technology fields are closely related (based on a higher number of cross citations), are characterized by wide technological scope, and are the result of an inter-firm collaboration. In contrast to previous findings, the results show that the more complex the technologies involved, the less the likelihood of their convergence or fusion. The correlation between fusion likelihood and the characteristics of the merging fields could help managers and policymakers to predict the emergence of new technology areas.  相似文献   
82.
We consider a sequence of financial markets that converges weakly in a suitable sense and maximize a behavioral preference functional in each market. For expected concave utilities, it is well known that the maximal expected utilities and the corresponding final positions converge to the corresponding quantities in the limit model. We prove similar results for nonconcave utilities and distorted expectations as employed in behavioral finance, and we illustrate by a counterexample that these results require a stronger notion of convergence of the underlying models compared to the concave utility maximization. We use the results to analyze the stability of behavioral portfolio selection problems and to provide numerically tractable methods to solve such problems in complete continuous‐time models.  相似文献   
83.
We develop a Generalized Nash Equilibrium network model for post-disaster humanitarian relief by nongovernmental organizations (NGOs). NGOs derive utility from providing relief supplies to victims of the disaster at demand points in a supply chain context while competing with each other for financial funds provided by donations. The shared constraints consist of lower and upper bounds for demand for relief items at the demand points to reduce materiel convergence or congestion. This game theory problem is reformulated as an optimization problem and numerical examples and a theoretical case study on Hurricane Katrina given.  相似文献   
84.
This study examines the effect of meeting space capacity on hotel operating performance. We use Resource-Based View (RBV) of the firm as the theoretical foundation. We employ a national-level dataset with more than 20,000 hotels in the United States for the 2007–2012 period. We find that meeting space has a non-linear effect on hotel operating performance. That is, at low levels of meeting space, meeting space capacity is negatively related to hotel operating performance. At high levels of meeting space, meeting space capacity has a positive influence on operating performance. These findings provide insights for hotel owners, developers and practitioners in planning hotel meeting space capacity.  相似文献   
85.
梁玮健 《价值工程》2012,31(15):84-85
社会交往是当代博物馆公共活动的核心内容。公共交往空间的设计在新建博物馆设计中的地位越来越重要。本文对在这种趋势下的博物馆公共交往空间设计进行案例分析和研究,试图归纳出其发展规律。  相似文献   
86.
This paper uses three classes of univariate time series techniques (ARIMA type models, switching regression models, and state-space/structural time series models) to forecast, on an ex post basis, the downturn in U.S. housing prices starting around 2006. The performance of the techniques is compared within each class and across classes by out-of-sample forecasts for a number of different forecast points prior to and during the downturn. Most forecasting models are able to predict a downturn in future home prices by mid 2006. Some state-space models can predict an impending downturn as early as June 2005. State-space/structural time series models tend to produce the most accurate forecasts, although they are not necessarily the models with the best in-sample fit.  相似文献   
87.
This article explores and theorizes the ways in which urban space and political contestations are mapped onto each other. The ethnography illustrates the multifaceted transformations in a notoriously secularist neighborhood of ?stanbul, Te?vikiye, as it first turns into a high‐consumption locality in the post‐1980s, then into a high‐conflict urban space in the new millennium on the arrival of Muslim high‐spenders, particularly headscarved women. Aiming to fill the gap left by the absence of spatial analysis from political science and political sociology, I argue that the urban neighborhood becomes central for political contestation when both government and opposition fail to protect and secure liberties and rights. Now that devout Muslims are integrated into highly contested urban sites and share bourgeois lifestyles, ordinary people act in defense of their ‘sphere’ of freedom and privacy. This new territoriality is largely symptomatic of increasing fears of losing freedom, privacy and social status. This spatial defensiveness is reinforced by people's decreasing trust in, and increasing demands from, the state for the protection and security of their rights and liberties. My overarching argument is that exclusive attention to the bipolar clash between devout Muslims and secularists under the rubric of ‘neighborhood wars’ obscures multipolar conflicts around the discontents stemming from authoritarianism and democratization.  相似文献   
88.
刘新燕 《价值工程》2012,31(20):73-75
设计依托结合姚店工业区总体规划,在充分考虑现有自然条件的前提下,挖掘当地工业历史和文化,营建与新区发展相适应的具有文化内涵并突出生态型的绿地环境景观系统。为工业区可持续发展打造坚实的物质和文化基础。  相似文献   
89.
"双评价"(资源环境承载能力评价和国土空间开发适宜性评价)作为构建国土空间基本战略格局的科学基础尚未延伸至海洋层面。海域"双评价"作为沿海地区国土空间规划工作的重要内容,存在理论缺失、技术方法不完善等问题。文章以海域功能理论为基础,从人类海洋活动出发,探索海域"双评价"的实践方案,建立"双评价"到海域利用优化的科学逻辑,指出基于"双评价"的海域利用冲突识别是海洋空间规划的关键。以温州市海域为例,基于本底资源从空间、渔业、环境和生态四方面进行单要素承载力测算,以此获得海域综合承载力作为监测预警的标志。选择渔业用海和建设用海两类典型用海进行适宜性分析,确定海洋空间利用的最优布局,判断海域利用空间冲突。结果表明:温州市沿海区县的海洋承载能力差异较大,资源环境分化严重,龙湾区与洞头区渔业资源开发超载;乐清市与龙湾区的海洋环境超载。渔业用海适宜面积占比较低且分布于远海地带。不适宜区域集中于瓯江、飞云江、鳌江三江入海口岸海域。建设用海适宜区域集中于近岸海域,远海区域距离城镇与交通较远,自然条件中水深较深,成本较高。苍南县和平阳县海域利用冲突较少,用海布局合理。乐清市、龙湾区与洞头区存在显著冲突。"双评价"的实践与应用是指导沿海地区海洋经济发展与海洋资源保护的关键,能够综合识别海洋利用的冲突,有助于沿海地区海洋空间规划。  相似文献   
90.
社区公园是老年人户外活动的主要场所。研究社区 公园空间与老年人户外活动行为的关系,对于满足老年人活 动需求、应对人口老龄化问题具有重要意义。以南京市郑和 公园为研究对象,在实地测绘的基础上,定义公园空间的类 型,并分析各类空间的构成特征。选取公园中5个样本空间进 行观测,从时间和空间2个维度分析老年人公园活动的行为特 征。针对占公园活动人数绝大多数的8种活动,运用数据分析 和ArcGIS技术对行为与空间的关联性进行分析,结合访谈和 Nvivo质性分析发现,空间的尺度、围合性与开敞性、是否受 干扰、景观质量、庇护性是老年人活动空间选择的主要动因; 座椅、遮阴要素、大面积铺装、照明设施、置物设施等则是老 年人需要的空间要素。  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