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   2329篇
  免费   85篇
  国内免费   16篇
财政金融   265篇
工业经济   169篇
计划管理   650篇
经济学   342篇
综合类   100篇
运输经济   65篇
旅游经济   69篇
贸易经济   402篇
农业经济   194篇
经济概况   174篇
  2024年   4篇
  2023年   36篇
  2022年   14篇
  2021年   40篇
  2020年   94篇
  2019年   62篇
  2018年   60篇
  2017年   110篇
  2016年   90篇
  2015年   59篇
  2014年   114篇
  2013年   419篇
  2012年   106篇
  2011年   189篇
  2010年   116篇
  2009年   124篇
  2008年   133篇
  2007年   94篇
  2006年   90篇
  2005年   85篇
  2004年   52篇
  2003年   46篇
  2002年   37篇
  2001年   37篇
  2000年   33篇
  1999年   23篇
  1998年   28篇
  1997年   27篇
  1996年   21篇
  1995年   17篇
  1994年   11篇
  1993年   10篇
  1992年   11篇
  1991年   5篇
  1990年   1篇
  1989年   5篇
  1988年   2篇
  1987年   5篇
  1986年   1篇
  1985年   11篇
  1984年   3篇
  1983年   3篇
  1982年   2篇
排序方式: 共有2430条查询结果,搜索用时 296 毫秒
61.
The profound financial crisis generated by the collapse of Lehman Brothers and the European sovereign debt crisis in 2011 have caused negative values of government bond yields both in the USA and in the EURO area. This paper investigates whether the use of models which allow for negative interest rates can improve option pricing and implied volatility forecasting. This is done with special attention to foreign exchange and index options. To this end, we carried out an empirical analysis on the prices of call and put options on the US S&P 500 index and Eurodollar futures using a generalization of the Heston model in the stochastic interest rate framework. Specifically, the dynamics of the option’s underlying asset is described by two factors: a stochastic variance and a stochastic interest rate. The volatility is not allowed to be negative, but the interest rate is. Explicit formulas for the transition probability density function and moments are derived. These formulas are used to estimate the model parameters efficiently. Three empirical analyses are illustrated. The first two show that the use of models which allow for negative interest rates can efficiently reproduce implied volatility and forecast option prices (i.e. S&P index and foreign exchange options). The last studies how the US three-month government bond yield affects the US S&P 500 index.  相似文献   
62.
To avoid the current paradoxes of the global agro-food system it is necessary to define and implement a viable agricultural sustainable model, combining satisfaction of food needs and land preservation. A possible solution can be found in a holistic production system consistent with a sustainable development model, designed to satisfy diverse “local” economies. The conservation agriculture (CA) could be a part of this model, as it includes a set of best practices available to preserve agrarian soil and its biodiversity. Briefly, we cover the CA background in Europe followed by the evaluation of its impact in terms of private/public interest, using the sustainability’s metric.To test the viability of a model based on CA in “local conditions”, we compare economic performance of different conservation practices (i.e. minimum and no tillage) to that of conventional agriculture in a typical Mediterranean environment – Collina Materana – in Southern Italy (Basilicata region). Our findings suggest that: i) CA can actually be a viable alternative to conventional systems; ii) in Mediterranean agricultural areas CA has yield advantages especially during dry years, when conservation techniques increase water supply to crops; iii) public support is needed to direct farming choices in fact without financial incentives these practices would be not widely accepted and diffused; iv) European policy makers have to recognized the positive benefits of CA and pay them as ecosystem services in the framework of Good Agricultural Environmental Conditions and the present CAP subsidies.  相似文献   
63.
This article develops theory about an agency problem affecting the strategic human capital (SHC) of the firm. It proposes three categories of SHC‐related choices managers must make that imply a trade‐off between near‐ and long‐term performance. Dispersed shareholding, firm coverage by securities analysts, and their practice of publishing quarterly earnings forecasts are argued to entail a bias in management incentives, shifting the balance in this trade‐off toward near‐term performance. To restore the balance, securities analysts would need to distinguish transitory from recurring effects of SHC‐related choices in their valuation models (e.g., treating certain labor cost savings during cyclical downturns as transitory). Restoring the balance would also require them to anticipate long‐term effects in their long‐term earnings forecasts (e.g., long‐term positive effects of retaining employees with valuable skills during cyclical downturns). The article discusses specific transitory cost effects and long‐term effects they could potentially take into account. The skills and incentives needed by analysts to account for such effects are argued to vary across firm segments.  相似文献   
64.
Public school lunch programs in the United States are contested political terrains shaped by government agencies, civil society activists, and agri-food companies. The particular organization of these programs has consequences for public health, social justice, and ecological sustainability. This contribution draws on political economy, critical food studies, and feminist economics to analyze the US National School Lunch Program, one of the world's oldest and largest government-sponsored school lunch programs. It makes visible the social and environmental costs of the “heat-and-serve” economy, where widely used metrics consider only the speed and volume of service as productive work. This study demonstrates that such a narrow understanding of the labor of lunch devalues care and undercuts the potential for school food provisioning to promote ecological and feminist goals. Further, it proposes a “high road” alternative and outlines an agenda for reorganizing school food provisioning to maximize care in all its dimensions.  相似文献   
65.
66.
The present article offers a concise theoretical conceptualization and operational analysis of the contribution of innovation to regional development. The latter concepts are closely related to geographical proximity, knowledge diffusion and filters and clustering. Institutional innovation profiles and regional patterns of innovation are two mutually linked, novel conceptual elements in this article. Next to a theoretical framing, the article employs the regional innovation systems concept as a vehicle to analyse institutional innovation profiles. Our case study addresses three Portuguese regions and their institutions, included in a web-based inventory of innovation agencies which offered the foundation for an extensive database. This data-set was analysed by means of a recently developed principal coordinates analysis followed by a Logistic Biplot approach (leading to a Voronoi mapping) to design a systemic typology of innovation structures where each institution is individually represented. There appears to be a significant difference in the regional innovation patterns resulting from the diverse institutional innovation profiles concerned. These profiles appear to be region specific. Our conclusion highlights the main advantages in the use of the method used for policy-makers and business companies.  相似文献   
67.
This study examines (i) the impact of market drivers of sustainability on the adoption of sustainability learning capabilities and (ii) the moderating role of sustainability control systems (SCS) on the relationship between market drivers of sustainability and sustainability learning capabilities. Drawing on the levers of control framework, stakeholder theory and organisational learning literature, survey data were collected from 175 large scale local and multinational companies operating in Sri Lanka. Findings reveal that market drivers of sustainability have a significant positive impact on sustainability learning capabilities. Whereas the interactive use of SCS shows a positive moderating impact, the diagnostic use of SCS shows a negative impact. The study enhances our understanding of (i) the influence of market drivers of sustainability on the adoption of sustainability learning capabilities and (ii) the use of SCS in enabling sustainability learning capabilities. The study reveals novel insights for managers responding to changing market drivers of sustainability, on how to (re)align different uses of SCS to enable sustainability learning capabilities.  相似文献   
68.
在自我决定理论的基础上探讨高绩效工作系统对不同动机员工沉默行为的影响机制及差异性。研究结果表明:(1)高绩效工作系统对员工默许沉默、防御沉默和漠视沉默行为具有显著的抑制作用;(2)高绩效工作系统能通过自主需求满意度、能力需求满意度和关系需求满意度的提升降低员工的默许沉默行为;(3)高绩效工作系统能通过关系需求满意度的提升降低员工的防御沉默行为;(4)高绩效工作系统通过自主需求满意度、能力需求满意度和关系需求满意度的提升降低员工的漠视沉默行为。  相似文献   
69.
This paper investigates the extent to which cross-country differences in aggregate participation rates can be explained by differences in tax-benefit systems. We take the example of two countries, the Czech Republic and Hungary, which – despite a lot of similarities – differ markedly in labour force participation rates. Using comparable individual-level labour supply estimates, we simulate how the aggregate participation rate would change in one country if the other country’s tax and social welfare system were adopted. The estimation results for the two countries are quite similar, suggesting that individual preferences are essentially identical in the two countries. The simulation results show that about one-third of the difference in the participation rates of the 15–74 year-old population and more than two-thirds of the participation of the prime-age population can be explained by differences in the tax-benefit systems.  相似文献   
70.
The purpose of this work is to apply the servicization of enterprise information systems in maintenance, particularly in the management of the maintenance process of the component parts of trains. Service Oriented Architecture (SOA) is an architectural approach that permits servicization since it provides a flexible set of design principles used during the modeling practices (abstraction and realization). With a view to supporting the model-driven engineering of software systems, Mode Driven Architecture (MDA) is a design approach delivering a set of guidelines for the configuring of specifications in systems development. Therefore, the combination of these two approaches can be fruitful to address the challenging issues the enterprise information system is facing today. Our study is based on a methodological approach using the MDA models for the automatic generation of web service. The case study concerns a Railways Maintenance Workshop (RMW) at Sidi Bel Abbes (Algeria). Finally, the information system for the management of maintenance of the component parts of passengers and baggage railcars, using the generated solution, is realized and deployed. This software helps to have better management of the RMW by the effective planning of interventions, improve performance by increasing reliability, traceability, and availability of the equipment (parts).  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