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   149441篇
  免费   4391篇
  国内免费   26篇
财政金融   25434篇
工业经济   11542篇
计划管理   21481篇
经济学   28864篇
综合类   1456篇
运输经济   963篇
旅游经济   2497篇
贸易经济   23428篇
农业经济   6057篇
经济概况   16820篇
水利工程   15022篇
信息产业经济   7篇
邮电经济   287篇
  2021年   1078篇
  2020年   1799篇
  2019年   2640篇
  2018年   2673篇
  2017年   2743篇
  2016年   3078篇
  2015年   2376篇
  2014年   3802篇
  2013年   16349篇
  2012年   4708篇
  2011年   4473篇
  2010年   3958篇
  2009年   4652篇
  2008年   4173篇
  2007年   3563篇
  2006年   3934篇
  2005年   3895篇
  2004年   3467篇
  2003年   3076篇
  2002年   3091篇
  2001年   2909篇
  2000年   2727篇
  1999年   2668篇
  1998年   2493篇
  1997年   2592篇
  1996年   2428篇
  1995年   2218篇
  1994年   2233篇
  1993年   2214篇
  1992年   2289篇
  1991年   2124篇
  1990年   2007篇
  1989年   1897篇
  1988年   1803篇
  1987年   1808篇
  1986年   1819篇
  1985年   2602篇
  1984年   2502篇
  1983年   2290篇
  1982年   2164篇
  1981年   2113篇
  1980年   2118篇
  1979年   2039篇
  1978年   1867篇
  1977年   1825篇
  1976年   1632篇
  1975年   1470篇
  1974年   1399篇
  1973年   1404篇
  1972年   1104篇
排序方式: 共有10000条查询结果,搜索用时 656 毫秒
101.
The centrality of cross‐functional integration (CFI) to supply chain theory and practice has long been recognized. Yet researchers continue to struggle with consistently defining or measuring the CFI construct, thus limiting the utility of CFI research. This research develops (1) a comprehensive definition of CFI that synthesizes previous supply chain research and (2) a valid set of scale items that measure the conceptual domain outlined by this definition. The goal is to build a common foundation for extending knowledge on CFI's antecedents and consequences, and ultimately to improve scholars’ ability to guide a broader practitioner community still struggling to achieve integration in their organizations.  相似文献   
102.
103.
The present research attempts to qualitatively explore the motivators and barriers of organic food consumption in the Indian context. The data were collected using semistructured in‐depth interviews and analyzed using grounded theory. The theoretical sampling technique was used to interview 34 consumers who have purchased organic food in the past. The findings reported health consciousness, environmental consciousness, social identity, consumer ethnocentrism, and concern for farmers as the factors that motivate organic food purchase among consumers. The factors such as high prices of organic food, unavailability, trust issues, and limited marketing communications from the firms were identified as major barriers to organic food purchase and consumption. The study is one of the initial attempts to qualitatively explore the consumers' motivation for organic food consumption in the Indian context. The findings will help policymakers to devise suitable strategies so that they can effectively target the organic food choices by understanding the motivators/barriers, and promote the sustainable lifestyle in the society, as food consumption plays a crucial role in achieving environmental sustainability.  相似文献   
104.
Anthropogenic influences, including climate change, are increasing river temperatures in northern and temperate regions and threatening the thermal habitats of native salmonids. When river temperatures exceed the tolerance levels of brook trout and Atlantic salmon, individuals exhibit behavioural thermoregulation by seeking out cold‐water refugia – often created by tributaries and groundwater discharge. Thermal infrared (TIR) imagery was used to map cold‐water anomalies along a 53 km reach of the Cains River, New Brunswick. Trout and salmon parr did not use all identified thermal anomalies as refugia during higher river temperature periods (>21°C). Most small‐bodied trout (8–30 cm) were observed in 80% of the thermal anomalies sampled. Large‐bodied trout (>35 cm) required a more specific set of physical habitat conditions for suitable refugia, that is, 100% of observed large trout used 30% of the anomalies sampled and required water depths >65 cm within or adjacent to the anomaly. Densities of trout were significantly higher within anomalies compared with areas of ambient river temperature. Salmon parr were less aligned with thermal anomalies at the observed temperatures, that is, 59% were found in 65% of the sampled anomalies; and densities were not significantly different within/ outside anomalies. Salmon parr appeared to aggregate at 27°C, and after several events over 27°C variability in aggregation behaviour was observed – some fish aggregated at 25°C, others did not. We stipulate this is due to variances of thermal fatigue. Habitat suitability curves were developed for velocity, temperature, depth, substrate, and deep water availability to characterize conditions preferred by fish during high‐temperature events. These findings are useful for managers as our climate warms, and can potentially be used as a tool to help conserve and enhance thermal refugia for brook trout and Atlantic salmon in similar systems.  相似文献   
105.
Equipment of the Krasnoyarsk HPP is considered as an example to analyze the dependence of crack formation in runner blades on the operating conditions of t  相似文献   
106.
107.
Both soft, noncontractible, and hard, contractible, information are informative about managerial ability and future firm performance. If a manager's future compensation depends on expectations of ability or future performance, then the manager has implicit incentives to affect the information. We examine the real incentive effects of soft information in a dynamic agency with limited commitment. When long-term contracts are renegotiated, the rewards for future performance inherent in long-term contracts allow the principal partial control over the implicit incentives. This is because the soft information affects the basis for contract renegotiation. With short-term contracts, the principal has no control over the basis for contract negotiation, and thus long-term contracts generally dominate short-term contracts. With long-term contracts, the principal's control over implicit incentives is characterized in terms of effective contracting on an implicit aggregation of the soft information that arises from predicting (forming expectations of) future performance. We provide sufficient conditions for soft information to have no real incentive effects. In general, implicit incentives not controllable by the principal include fixed effects, such as career concerns driven by labor markets external to the agency. When controllable incentives span the fixed effects of career concerns, the latter have no real effects with regard to total managerial incentives—they would optimally be the same with or without career concerns. Our analysis suggests empirical tests for estimating career concerns that should explicitly incorporate noncontractible information.  相似文献   
108.
This article provides new information and data on the work and pay of skilled and semi-skilled men on a large London construction project in the early 1700s. It offers firm-level evidence on the employment relation in the construction industry at the time and sheds some light on the number of days worked per year and per week, showing that employment was more irregular and seasonal than current estimates of income infer. The patterns are considered in the context of new debates about industriousness and economic growth.  相似文献   
109.
110.
This article addresses one under‐studied aspect of Charles I's finances during his Personal Rule: the licensing of tobacco retailers. While it was ultimately a failed project, the tobacco retail licence project was fiscally successful before the transformative events of the 1640s triggered its demise. The project enabled tobacco retail licensees to establish commercial outlets for the marketing of tobacco throughout England and Wales, and cooperation with pre‐existing officeholders contributed to the apprehension of unlicensed retailers. Ultimately, the geographic breadth of tobacco licences translated into much‐needed royal revenue which, when added to other projects and patents, contributed to the king's financial survival. The evidence presented here suggests that we may want to rethink some of our assumptions for how the process of state formation worked and that earlier seventeenth‐century ‘prototypes’ of taxation were more fiscally successful than previously recognized.  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