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11.
Brigitte Eierle 《Accounting, Business & Financial History》2005,15(3):279-315
Based on a contingent perspective of accounting change, this paper reviews the historical development of differential reporting in Germany, by drawing on primary and secondary sources. The main objective of the paper is to shed light on the driving forces and main influential parameters that have shaped the existing differential reporting framework. This historical approach supplies interesting insights for the current discussion on differential reporting in Germany produced by the EU Regulation on the application of International Accounting Standards. 相似文献
12.
Conditional probability distributions seem to have a bad reputation when it comes to rigorous treatment of conditioning. Technical arguments are published as manipulations of Radon–Nikodym derivatives, although we all secretly perform heuristic calculations using elementary definitions of conditional probabilities. In print, measurability and averaging properties substitute for intuitive ideas about random variables behaving like constants given particular conditioning information.
One way to engage in rigorous, guilt-free manipulation of conditional distributions is to treat them as disintegrating measures—families of probability measures concentrating on the level sets of a conditioning statistic. In this paper we present a little theory and a range of examples—from EM algorithms and the Neyman factorization, through Bayes theory and marginalization paradoxes—to suggest that disintegrations have both intuitive appeal and the rigor needed for many problems in mathematical statistics. 相似文献
One way to engage in rigorous, guilt-free manipulation of conditional distributions is to treat them as disintegrating measures—families of probability measures concentrating on the level sets of a conditioning statistic. In this paper we present a little theory and a range of examples—from EM algorithms and the Neyman factorization, through Bayes theory and marginalization paradoxes—to suggest that disintegrations have both intuitive appeal and the rigor needed for many problems in mathematical statistics. 相似文献
13.
本文通过调整迭代解码过程中系统位接收值的加权系数,提出了一种Turbo码加权迭代解码算法。该算法改变了迭代运算后Turbo码解码器输出软值中系统位接收值信息和它的外部估计信息的比重,使Turbo码无论在低信噪比或是在高信噪比时均具有优良的纠错性能。仿真结果显示,采用Turbo码加权迭代解码算法,不仅能提高Turbo码的收敛速度,而且能进一步降低Turbo码解码时的地板值,使Turbo码的比特误码率在高、低信噪比时都能够得到进一步改善。 相似文献
14.
电力机车变压器的优化设计,采用遗传算法是比较好的选择,但传统遗传算法存在一些弊端,文章从编码方式、遗传操作等几个方面探讨了如何对其进行改进,并使用Visual C++编写了一套设计软件,实践证明这种改进是有效的。 相似文献
15.
In this paper we present an effective algorithm for the construction and the identification of two-level nonisomorphic orthogonal
arrays. Using this algorithm, we identify and list a full catalogue of nonisomorphic orthogonal arrays with parameters OA(24,7,2,t), OA(28,6,2,t) and OA(32,6,2,t), t ≥ 2. Some statistical properties of these designs are also considered. 相似文献
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文章概述两层规划问题在交通领域、资源分配、委托代理以及供应链管理中的应用并讨论了线性和非线性两种两层规划问题,总结了极点算法、下降迭代、惩罚函数和分支定界算法,并进行了评价,最后进一步探讨了两层规划问题的应用前景和算法的发展方向。 相似文献
18.
R&D externalities can imply ranges of aggregate increasing returns to scale in R&D. As a consequence several equilibria can exist involving different numbers of firms and different R&D investment levels. In a theoretical model the equilibrium dynamics are analyzed, showing that cyclical fluctuations of the number of firms and R&D investment may be expected, and that the long-run equilibrium is highly sensitive to investors' initial beliefs. The model is tested empirically using a unique database comprising competing firms in various R&D races. 相似文献
19.
Nine macroeconomic variables are forecast in a real-time scenario using a variety of flexible specification, fixed specification, linear, and nonlinear econometric models. All models are allowed to evolve through time, and our analysis focuses on model selection and performance. In the context of real-time forecasts, flexible specification models (including linear autoregressive models with exogenous variables and nonlinear artificial neural networks) appear to offer a useful and viable alternative to less flexible fixed specification linear models for a subset of the economic variables which we examine, particularly at forecast horizons greater than 1-step ahead. We speculate that one reason for this result is that the economy is evolving (rather slowly) over time. This feature cannot easily be captured by fixed specification linear models, however, and manifests itself in the form of evolving coefficient estimates. We also provide additional evidence supporting the claim that models which ‘win’ based on one model selection criterion (say a squared error measure) do not necessarily win when an alternative selection criterion is used (say a confusion rate measure), thus highlighting the importance of the particular cost function which is used by forecasters and ‘end-users’ to evaluate their models. A wide variety of different model selection criteria and statistical tests are used to illustrate our findings. 相似文献
20.