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141.
Abstract

The popular domain-specific approach to risk reduction created the illusion that efficient risk reduction can be delivered successfully solely by using methods offered by the specific domain. As a result, many industries have been deprived of efficient risk reducing strategy and solutions. This paper argues that risk reduction is underlined by domain-independent methods and principles which, combined with knowledge from the specific domain, help to generate effective risk reduction solutions. In this respect, the paper introduces a powerful method for reducing the likelihood of computational errors based on combining the domain-independent method of segmentation and local knowledge of the chain rule for differentiation. The paper also demonstrates that lack of knowledge of domain-independent principles for risk reduction misses opportunities to reduce the risk of failure even in a mature field like stress analysis. The domain-independent methods for risk reduction do not rely on reliability data or knowledge of physical mechanisms underlying possible failure modes and are particularly well suited for developing new designs, with unknown failure mechanisms and failure history. In many cases, the reliability improvement and risk reduction by using the domain-independent methods reduces risk at no extra cost or at a relatively small cost. The presented domain-independent methods work across unrelated domains and this is demonstrated by the supplied examples which range from various areas of engineering and technology, computer science, project management, health risk management, business and mathematics. The domain-independent risk reduction methods presented in this paper promote building products and systems characterised by high-reliability and resilience.  相似文献   
142.
The analysis of the sustainability of public sector finances requires an accounting of all future revenues and all future spending that we would expect, under current tax laws and current entitlements. The classical calculation does not acknowledge the inherent uncertainty of the future economic and demographic developments, so the results can be misleading. Our aim is to produce a more robust summary of the sustainability of the public sector than the one currently available. By taking a forecasting point of view, our formulation takes into account the uncertainty of future productivity, stock and bond markets, and demography. Methodological complications that arise in the stochastic setting are discussed. Estimates of the relative roles of economics and demographics in the uncertainty of public net liabilities are presented.  相似文献   
143.
This article compares the accuracy of vector autoregressive (VAR), restricted vector autoregressive (RVAR), Bayesian vector autoregressive (BVAR), vector error correction (VEC) and Bayesian vector error correction (BVEC) models in forecasting the exchange rates for five Central and Eastern European currencies (Czech Koruna, Hungarian Forint, Polish Zloty, Slovak Koruna and Slovenian Tolar) against the Euro and the US dollar. Among the specifications composing this battery of multivariate time series models, those with the smallest prediction error still fail to reject the test of equality of forecasting accuracy against the random walk model in short-term predictions, with the exception of the Slovenian Tolar/Euro exchange rate.First version received: October 2002/Final version received: September 2003The authors are grateful to two anonymous referees and the participants in the workshop Monetary and Exchange Rate Strategies Related to the Current European Unions Enlargement Processes, held in Leuven in September 2000, for very helpful comments.  相似文献   
144.
调查分析了中原油田钻井液用合成聚合物降滤失剂产品的应用现状.提出了目前产品质量及检验标准中存在的问题,通过现场及室内实验研究,提出了解决问题的方法及建议。  相似文献   
145.
李峰 《价值工程》2011,30(2):262-262
中国的高等职业教育已经进入一个崭新的阶段,无论是招生数量,还是师资力量都呈现出一个全新的面貌。但相对于本科教育还是存在很多不足之处。本文就高职院校的数学教学提出一些个人的看法,以期与各位朋友共同探讨。  相似文献   
146.
In many applications of regression‐based Monte Carlo methods for pricing, American options in discrete time parameters of the underlying financial model have to be estimated from observed data. In this paper suitably defined nonparametric regression‐based Monte Carlo methods are applied to paths of financial models where the parameters converge toward true values of the parameters. For various Black–Scholes, GARCH, and Levy models it is shown that in this case the price estimated from the approximate model converges to the true price.  相似文献   
147.
The paper is based on the thesis that IT controlling suffers from two integration deficits with regard to its methods base: On the one hand, this is a lack of synchronization between research on IT controlling methods and developments in practice; on the other hand, a lack of integration of IT controlling methods with methods of business and information systems engineering (BISE). Based on this assumption, the paper investigates historical developments in IT controlling research and practice to derive theses about the present state of method integration. The analysis finds indications for further potential for method integration and identifies these potentials. Requirements towards method integration are derived from an analysis of the identified integration potentials and two examples illustrate how to realize further integration. Accepted after two revisions by the editors of the special focus. This article is also available in German in print and via http://www.wirtschaftsinformatik.de: Strecker S, Kargl H (2009) Integrationsdefizite des IT-Controllings – Historischer Hintergrund, Analyse von Integrationspotenzialen und Methodenintegration. doi: 10.1007/s11576-009-0175-9.  相似文献   
148.
This paper considers methods for forecasting macroeconomic time series in a framework where the number of predictors, N, is too large to apply traditional regression models but not sufficiently large to resort to statistical inference based on double asymptotics. Our interest is motivated by a body of empirical research suggesting that popular data-rich prediction methods perform best when N ranges from 20 to 40. In order to accomplish our goal, we resort to partial least squares and principal component regression to consistently estimate a stable dynamic regression model with many predictors as only the number of observations, T, diverges. We show both by simulations and empirical applications that the considered methods, especially partial least squares, compare well to models that are widely used in macroeconomic forecasting.  相似文献   
149.
李勇 《价值工程》2012,31(16):72-73
本文依托北京动车段走行线悬臂式挡土墙基坑支护工程,介绍了旋喷桩用作既有线施工防护的安全性与经济性,根据地质情况对施工参数的适当调整,可以大大节约工期,降低成本。为以后类似施工提供一种思路、方法。  相似文献   
150.
统计资料显示,近年中国旅游业总收入以超过10%的速度增长。旅游业的可持续发展需要旅游管理高等教育提供人才保障。但是目前中国旅游管理高等教育供需错位现象明显,比如必修课、选修课设置比例需要调整,教学内容需要优化,生源不足且毕业后流失严重的现状需要改观,适合本专业的人才培养模式有待继续探索。以经济学理论、模型为工具,运用到西方经济学中经济人假设和定义,理性预期理论,效用最大化理论,以及外在性与公共物品理论,探索中国未来旅游管理高等教育改革思路。  相似文献   
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