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   3380篇
  免费   115篇
  国内免费   3篇
电工技术   69篇
综合类   4篇
化学工业   845篇
金属工艺   60篇
机械仪表   68篇
建筑科学   124篇
矿业工程   23篇
能源动力   79篇
轻工业   293篇
水利工程   29篇
石油天然气   11篇
无线电   291篇
一般工业技术   640篇
冶金工业   314篇
原子能技术   24篇
自动化技术   624篇
  2023年   25篇
  2022年   56篇
  2021年   88篇
  2020年   48篇
  2019年   62篇
  2018年   75篇
  2017年   72篇
  2016年   91篇
  2015年   93篇
  2014年   122篇
  2013年   172篇
  2012年   189篇
  2011年   247篇
  2010年   173篇
  2009年   172篇
  2008年   177篇
  2007年   156篇
  2006年   150篇
  2005年   122篇
  2004年   129篇
  2003年   77篇
  2002年   102篇
  2001年   66篇
  2000年   56篇
  1999年   65篇
  1998年   101篇
  1997年   75篇
  1996年   53篇
  1995年   50篇
  1994年   38篇
  1993年   30篇
  1992年   28篇
  1991年   28篇
  1990年   21篇
  1989年   18篇
  1988年   21篇
  1987年   24篇
  1986年   9篇
  1985年   15篇
  1984年   14篇
  1983年   13篇
  1982年   13篇
  1981年   10篇
  1980年   12篇
  1979年   11篇
  1977年   15篇
  1976年   11篇
  1975年   12篇
  1972年   8篇
  1970年   10篇
排序方式: 共有3498条查询结果,搜索用时 15 毫秒
11.
12.
The effect of pressure on transition displacement between trickle and pulsed regimes (TPR: trickle-pulsed transition) in catalytic trickle bed reactors (CTBR) is not properly predicted by existing theoretical models and empirical correlations. Based on high pressure TPR data available to date, a modified Charpentier diagram is proposed to quantify directly the effect of pressure in non-foaming systems.  相似文献   
13.
14.
15.
A necessary and sufficient condition is given for a connected bipartite graph to be the incidence graph of a contact family of segments and points. We deduce that any four-connected three-colorable plane graph is the contact graph of a family of segments and that any four-colored planar graph without an induced C4 using four colors is the intersection graph of a family of straight line segments.  相似文献   
16.
An axisymmetrical model of a rapid nonisobaric heavily laden gas‐particle jet is developed. The model is based on the general functions for both axial and radial pressure distributions, which were discovered by a numerical study of rapid gas‐particle jets by the CFD code. The model equations were solved analytically. The results obtained by the model developed are in good agreement with those computed by the CFD code for a wide range of flow parameters.  相似文献   
17.
The investigation of a trichinosis outbreak in Auvergne, France identified 23 cases in 12 households living in two cities-Clermont-Ferrand and Montlu?on-between 15 February and 7 March 1991. One patient required intensive care, 15 had major symptoms, and seven had minor or no symptoms. Two case control studies demonstrated a significant (p < 0.01) association between eating horse meat and acute trichinosis. Veterinary services found that three supermarkets where the patients had bought horse meat during the suspected period had been supplied by a single wholesaler. The analysis of the wholesaler's records revealed that the implicated horse meat had been imported from a slaughterhouse in the United States. This outbreak occurred despite a requirement in France for all meat from horses slaughtered in France and in countries exporting meat to France to be examined systematically for trichinella.  相似文献   
18.

The present work proposes a solution to the challenging problem of registering two partial point sets of the same object with very limited overlap. We leverage the fact that most objects found in man-made environments contain a plane of symmetry. By reflecting the points of each set with respect to the plane of symmetry, we can largely increase the overlap between the sets and therefore boost the registration process. However, prior knowledge about the plane of symmetry is generally unavailable or at least very hard to find, especially with limited partial views. Finding this plane could strongly benefit from a prior alignment of the partial point sets. We solve this chicken-and-egg problem by jointly optimizing the relative pose and symmetry plane parameters. We present a globally optimal solver by employing the branch-and-bound paradigm and thereby demonstrate that joint symmetry plane fitting leads to a great improvement over the current state of the art in globally optimal point set registration for common objects. We conclude with an interesting application of our method to dense 3D reconstruction of scenes with repetitive objects.

  相似文献   
19.
Software product line engineering seeks to systematise reuse when developing families of similar software systems so as to minimise development time, cost and defects. To realise variability at the code level, product line methods classically advocate usage of inheritance, components, frameworks, aspects or generative techniques. However, these might require unaffordable paradigm shifts for developers if the software was not thought at the outset as a product line. Furthermore, these techniques can be conflicting with a company’s coding practices or external regulations. These concerns were the motivation for the industry–university collaboration described in this paper in which we developed a minimally intrusive coding technique based on tags. The approach was complemented with traceability from code to feature diagrams which were exploited for automated configuration. It is supported by a toolchain and is now in use in the partner company for the development of flight-grade satellite communication software libraries.  相似文献   
20.
The underlying property, its definition, and representation play a major role when monitoring a system. Having a suitable and convenient framework to express properties is thus a concern for runtime analysis. It is desirable to delineate in this framework the sets of properties for which runtime analysis approaches can be applied to. This paper presents a unified view of runtime verification and enforcement of properties in the Safety-Progress classification. First, we extend the Safety-Progress classification of properties in a runtime context. Second, we characterize the set of properties which can be verified (monitorable properties) and enforced (enforceable properties) at runtime. We propose in particular an alternative definition of ??property monitoring?? to the one classically used in this context. Finally, for the delineated sets of properties, we define specialized verification and enforcement monitors.  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