全文获取类型
收费全文 | 31454篇 |
免费 | 2601篇 |
国内免费 | 1783篇 |
专业分类
财政金融 | 2233篇 |
工业经济 | 1225篇 |
计划管理 | 5271篇 |
经济学 | 4802篇 |
综合类 | 2609篇 |
运输经济 | 325篇 |
旅游经济 | 496篇 |
贸易经济 | 3090篇 |
农业经济 | 2316篇 |
经济概况 | 2907篇 |
水利工程 | 10564篇 |
出版年
2024年 | 179篇 |
2023年 | 666篇 |
2022年 | 791篇 |
2021年 | 1086篇 |
2020年 | 1270篇 |
2019年 | 1108篇 |
2018年 | 1078篇 |
2017年 | 1389篇 |
2016年 | 1410篇 |
2015年 | 1308篇 |
2014年 | 2087篇 |
2013年 | 2510篇 |
2012年 | 2491篇 |
2011年 | 2762篇 |
2010年 | 2016篇 |
2009年 | 1930篇 |
2008年 | 2080篇 |
2007年 | 1947篇 |
2006年 | 1686篇 |
2005年 | 1412篇 |
2004年 | 1021篇 |
2003年 | 750篇 |
2002年 | 579篇 |
2001年 | 415篇 |
2000年 | 348篇 |
1999年 | 256篇 |
1998年 | 230篇 |
1997年 | 169篇 |
1996年 | 187篇 |
1995年 | 183篇 |
1994年 | 153篇 |
1993年 | 84篇 |
1992年 | 93篇 |
1991年 | 45篇 |
1990年 | 17篇 |
1989年 | 30篇 |
1988年 | 17篇 |
1987年 | 6篇 |
1986年 | 11篇 |
1985年 | 17篇 |
1984年 | 11篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 718 毫秒
51.
认股权证作为一种长期资金的筹资方式 ,其资本成本必须予以考虑。但是使用传统资本成本计算方法不能反映其真实成本。本文尝试使用B -S和CAPM模型来计算其资本成本 ,并用实例说明 相似文献
52.
Hardle Wolfgang; Herwartz Helmut; Spokoiny Vladimir 《The Journal of Financial Econometrics》2003,1(1):55-95
Price variations at speculative markets exhibit positive autocorrelationand cross correlation. Due to large parameter spaces necessaryfor joint modeling of variances and covariances, multivariateparametric volatility models become easily intractable in practice.We propose an adaptive procedure that identifies periods ofsecond-order homogeneity for each moment in time. To overcomethe high dimensionality of the problem we transform the multivariateseries into a set of univariate processes. We discuss thoroughlythe implementation of the adaptive technique. Theoretical andMonte Carlo results are given. We provide two applications ofthe new method. For a bivariate exchange rate series we comparethe multivariate GARCH approach with our method and find thelatter to be more in line with the underlying assumption ofindependently distributed innovations. Analyzing a 23-dimensionalvector of asset returns we underscore the case for adaptivemodeling in high-dimensional systems. 相似文献
53.
While the dynamic theory of production provides little insight towards identifying a specific functional form for the firm's technology, dynamic production analysis has been explored traditionally in a parametric framework. A nonparametric dynamic dual cost approach to production analysis is developed in this article. Recovering technological information from intertemporal cost minimizing behavior is possible without imposing a parametric functional form on the firm's technology. Nonparametric tests to analyze the structure of a dynamic technology are presented from a dynamic cost minimizing perspective. The empirical implementation of these tests is illustrated for a balanced panel data set of Pennsylvania dairy operators during the time period 1986–1992. 相似文献
54.
Loïc Cadiou Stphane Des Jean-Pierre Laffargue 《Journal of Economic Dynamics and Control》2003,27(11-12):1961
This paper presents a vintage capital model assuming putty–clay investment and perfect foresight. The model is written in discrete time and is simulated by using a second order relaxation algorithm. By computing the eigenvalues of the dynamic system, we have checked the conditions of existence and uniqueness of a solution (Blanchard and Kahn's conditions) and identified the echo effect that characterizes vintage capital models and the related dynamics of creation and destruction. By calibrating the model on French data, it has been proved useful to explain the medium-term movements in the distribution of income in France during the last three decades. 相似文献
55.
采用宽度平均的立面二维水温模型,通过分析支流和主库之间的相互影响,提出了支流与主库耦合的简化方法,建立了考虑支流影响的水库水温模型。在考虑有无支流影响的条件下,对水库水温分布、水库下泄水温和坝前垂向水温分布均作了比较,结果表明支流对水库水温分布有一定的影响,所建立支流与主库耦合的立面二维水温模型能够较好地反映存在支流影响的水库水温分布,预测水库水温分布比较合理。 相似文献
56.
Li Yu-cheng He Ming Dept.of Civil Engineering Dalian Univ.of Technology Dalian P.R.China 《水动力学研究与进展(B辑)》1993,(4)
Based on model test,the statistical distribution of extreme values of wave-current in-line forces acting on vertical circular cylinder is analyzed in this paper.It is shownthat the results calculated by the simplified method,proposed by authors,agree well with the testdata;Weibull distribution is also adoptable in the region of high KC number, and the shapeparameter a and scale parameter β are related well with KC number respectively. 相似文献
57.
The Graph Model for Conflict Resolution is a flexible methodology for systematically studying strategic conflicts in the real world, and is therefore a natural tool for negotiation support. The basic definitions underlying the graph model are reviewed, and the techniques for analysis and interpretation are discussed. The modeling and analysis of a case study, an international trade negotiation concerning the export of Canadian softwood lumber to the United States, are used to demonstrate the practical application of the Graph Model for Conflict Resolution as a negotiation support tool. The modeling and analysis is carried out using the GMCR software system. The ability of the Graph Model for Conflict Resolution to provide insights and advice to negotiators is emphasized. 相似文献
58.
The 1992–93 recession in the western states of Germany has been attributed, in substantial measure, to the macroeconomic consequences of policies to finance unification. Studies of the costs of unification have not attempted to measure the burden of the recession. We estimate a dynamic, panel model of household incomes using data from the German Socio-Economic Panel (GSOEP) and use it to forecast what these incomes would have been in 1992–94 without a recession. Using a ratio of actual to forecast incomes, we compare the relative burden of the recession across households. Our findings suggest that western households below the median income bore the brunt of the combined impact of unification and the recession of 1992–93.
JEL classification: P3, D3, E3. 相似文献
JEL classification: P3, D3, E3. 相似文献
59.
This paper demonstrates howadditional rents are generated in a fisherycharacterized by intraseasonal variation infish characteristics, including size,condition, and composition. Based on anexpanded conceptual model of the optimalharvest rule, fish characteristics affect preand post harvest production yields and outputprices. A dynamic empirical model, which uses asystem of quality characteristics and anhedonic equation, illustrates the complexrelationships and management choices associatedwith internalizing seafood qualitycharacteristics in a hake fishery. The modelretains the regulated open access managementsystem, but controls intertemporal andintersectoral quotas, production portfolios,and total allowable catch. Results demonstratethat including revenue-side effects frominternalizing fish quality can generatesignificantly greater rents and reduce therelative benefits of increased productionyields. If excluded, bioeconomic models canunderestimate the level of regulatory rentdissipation and overemphasize managementobjectives such as full utilization, whichcould misdirect processing decisions and resultin a suboptimal resource management plan.Implications for data collection,multidisciplinary analysis, and improvements inmarine resource management are discussed. 相似文献
60.
In this progress report, we first indicate the origins and early development of the Marshallian macroeconomic model (MMM) and briefly review some of our past empirical forecasting experiments with the model. Then we present recently developed one-sector, two-sector and n-sector models of an economy that can be employed to explain past experience, predict future outcomes and analyze policy problems. The results of simulation experiments with various versions of the model are provided to illustrate some of its dynamic properties that include “chaotic” features. Last, we present comments on planned future work with the model. 相似文献