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   408篇
  免费   39篇
  国内免费   41篇
电工技术   1篇
综合类   31篇
化学工业   8篇
机械仪表   10篇
建筑科学   26篇
矿业工程   3篇
能源动力   5篇
轻工业   2篇
水利工程   2篇
无线电   34篇
一般工业技术   11篇
冶金工业   102篇
原子能技术   1篇
自动化技术   252篇
  2023年   3篇
  2022年   5篇
  2021年   12篇
  2020年   11篇
  2019年   6篇
  2018年   7篇
  2017年   8篇
  2016年   18篇
  2015年   14篇
  2014年   24篇
  2013年   28篇
  2012年   35篇
  2011年   42篇
  2010年   25篇
  2009年   33篇
  2008年   31篇
  2007年   30篇
  2006年   15篇
  2005年   19篇
  2004年   11篇
  2003年   12篇
  2002年   16篇
  2001年   10篇
  2000年   4篇
  1999年   3篇
  1998年   3篇
  1997年   3篇
  1995年   3篇
  1994年   3篇
  1993年   2篇
  1990年   4篇
  1989年   4篇
  1987年   4篇
  1986年   5篇
  1985年   3篇
  1983年   2篇
  1979年   2篇
  1970年   1篇
  1967年   1篇
  1965年   3篇
  1964年   2篇
  1963年   2篇
  1962年   1篇
  1961年   4篇
  1960年   1篇
  1959年   1篇
  1958年   2篇
  1957年   2篇
  1955年   4篇
  1954年   2篇
排序方式: 共有488条查询结果,搜索用时 15 毫秒
1.
2.
This paper examines how personal income taxation has changed across countries and whether and how this has affected the taxation of owner-occupied dwellings. It presents a partial analysis as it focuses on imputed rent taxation and the mortgage interest deduction. Furthermore, the paper places housing taxation in a wider context by describing different benchmarks which could be used to assess the taxation of owner-occupied housing in different types of personal income tax. These international and theoretical points-of-departure are used to evaluate the taxation of owner-occupied housing in the Netherlands. The paper concludes that all along political arguments have conquered theoretical premises to the advantage of the owner occupier in comparison to the private landlord. It also concludes that the theoretical base in 2001 has become so weak that owner-occupied housing is in an exceptional position in comparison with other private wealth thus becoming an easy victim for future tax savings.  相似文献   
3.
The literature on housing markets suggests that house prices in almost all western economies can be explained by short-run demand-oriented variables and a long-run term. The basic principles of the theory are that the short-run fluctuations, which are based on recent price developments (shocks), occur due to market imperfection, while over the long term, causality with such fundamentals as income will recover. Nonetheless, many of the interesting questions in housing economics concern adjustments toward equilibrium. This paper seeks to identify a long-run equilibrium between interest payments and household income (interest-to-income ratio) instead of between house prices and income (price-to-income ratio).
Paul de VriesEmail:
  相似文献   
4.
A simplified model for total project cost is developed in this paper to meet the numerous requests from decision makers for a model that can be used to estimate the total project cost from the estimated cash flows and, more importantly, to check the accuracy of the project cost estimates in feasibility studies that require prudent decisions. It begins with a base cost estimate in constant dollars and discrete cash flows with discrete inflation rates as practised by the construction industry. The discrete inflation rates are used to estimate the current dollar costs of the project. The effects of inflation are estimated as escalation during construction. Using the future value concept, interest during construction is estimated, in a simplified approach, to estimate the total project cost. Data from an actual feasibility study is used to highlight the strengths and weaknesses of the simplified model. The model is extended to treat discrete cash flows with continuous inflation rates.  相似文献   
5.
乡村振兴战略下我国农村土地开发面临 着多元主体利益冲突与协调困境。以四川省3个村 庄作为研究对象,采用多案例对比、多主体分析 的研究思路,分别解析政府主导、市场主导、村 集体主导三种村庄土地开发路径的开发过程与 驱动机制,并总结其在利益分配方面的困境或不 足。研究结果表明,在公共利益、集体利益和个 人利益的博弈中,开发主体及行为动机差异是造 成利益冲突困境的根本原因。其中,政府和市场 主导的村庄土地开发存在较多的利益分配不协调 问题,而村集体主导能够较好地协调公共、集体 和个人利益的关系。在农村土地开发过程中协调 处理好利益主体的相互关系是解决问题的关键, 应当通过开发主体限制、平台构建、利益联结和 协商机制的确立,实现可持续的农村土地开发与 乡村振兴战略的全面推进。  相似文献   
6.
Usual methods of spectrum estimation allow very strong frequencies to affect the spectrum estimates at distant frequencies, because the weighting function (spectrum window) cannot be made identically zero over the rejected range of frequencies. To give bounds for this error, a pair of windows, one with positive side lobes (Bartlett), the other with negative side lobes (modified Bartlett), are used simultaneously. Thus we demonstrate the error reduction achieved by detrending and prewhitening an example economic time series. The details of the spectrum windows, and a discussion of confidence limits for the spectrum, are given in the appendix. A program for the IBM 650 is available.  相似文献   
7.
MiE is a facial involuntary reaction that reflects the real emotion and thoughts of a human being. It is very difficult for a normal human to detect a Micro-Expression (MiE), since it is a very fast and local face reaction with low intensity. As a consequence, it is a challenging task for researchers to build an automatic system for MiE recognition. Previous works for MiE recognition have attempted to use the whole face, yet a facial MiE appears in a small region of the face, which makes the extraction of relevant features a hard task. In this paper, we propose a novel deep learning approach that leverages the locality aspect of MiEs by learning spatio-temporal features from local facial regions using a composite architecture of Convolutional Neural Network (CNN) and Long Short Term Memory (LSTM). The proposed solution succeeds to extract relevant local features for MiEs recognition. Experimental results on benchmark datasets demonstrate the highest recognition accuracy of our solution with respect to state-of-the-art methods.  相似文献   
8.
This paper proposes the idea of combining “interest groups” with the practical decision information to classify the decision makers (DMs) in complex multi-attribute large-group decision-making (CMALGDM) problems in interval-valued intuitionistic fuzzy (IVIF) environment. It constructs a partial binary tree DEA-DA cyclic classification model to achieve the multiple groups’ classification of DMs. Not only does this method provide references for the classification of DMs when the decision information is known, but it also lays foundations for DMs’ effective weight determination and the aggregation of decision information. First, this paper normalizes all of the cost attributes into benefit attributes to avoid the wrong decision result. Second, it employs the C-OWA operator to transform IVIF number (IVIFN) samples into single-valued samples. With respect to this transformation, this paper provides the corresponding BUM functions of DMs according to their risk attitudes; therefore, the preference information of DMs can be more objectively aggregated. Third, this paper adopts the partial binary tree DEA-DA cyclic classification model to present an accurate classification of DMs. Thus, for each interest group, group members with different interest preferences can be distinguished and distributed to the appropriate groups. Finally, to show the feasibility and validity of the model, we give an illustrative example.  相似文献   
9.
We assume a financial market governed by a diffusion process reverting to a stochastic mean which is itself governed by an unobservable ergodic diffusion, similar to those observed in electricity and other energy markets. We develop a moment method algorithm for the estimation of the parameters of both the observable process and the unobservable stochastic mean. Our approach is contrasted with other methods for parameter estimation of partially observed diffusions, and applications to the modelling of interest rates and commodity prices are discussed.  相似文献   
10.
通过计算机辅助教学的介绍,对计算机辅助教学在化学课堂教学中的功能进行了分析,这些功能包括:课堂直观性好,化抽象为具体;丰富课堂内容,开阔学生视野;化学实验演示,一目了然;利用计算机设计课堂练习。抓住重点,突出难点;通过网络教学,激发学生学习的兴趣。  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