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   580篇
  免费   12篇
  国内免费   1篇
电工技术   5篇
化学工业   168篇
金属工艺   3篇
机械仪表   9篇
建筑科学   36篇
矿业工程   1篇
能源动力   13篇
轻工业   54篇
水利工程   7篇
石油天然气   3篇
无线电   60篇
一般工业技术   107篇
冶金工业   26篇
原子能技术   2篇
自动化技术   99篇
  2024年   13篇
  2023年   5篇
  2022年   10篇
  2021年   14篇
  2020年   16篇
  2019年   13篇
  2018年   13篇
  2017年   19篇
  2016年   17篇
  2015年   6篇
  2014年   20篇
  2013年   30篇
  2012年   31篇
  2011年   27篇
  2010年   23篇
  2009年   14篇
  2008年   28篇
  2007年   28篇
  2006年   22篇
  2005年   27篇
  2004年   21篇
  2003年   15篇
  2002年   15篇
  2001年   10篇
  2000年   12篇
  1999年   7篇
  1998年   11篇
  1997年   4篇
  1996年   7篇
  1995年   8篇
  1994年   5篇
  1993年   10篇
  1992年   5篇
  1990年   4篇
  1989年   3篇
  1988年   2篇
  1987年   7篇
  1986年   9篇
  1985年   9篇
  1984年   4篇
  1981年   6篇
  1980年   7篇
  1979年   3篇
  1978年   4篇
  1977年   2篇
  1976年   4篇
  1974年   4篇
  1972年   3篇
  1968年   7篇
  1967年   2篇
排序方式: 共有593条查询结果,搜索用时 15 毫秒
21.
Scope of glass as material of construction in plant engineering. In conjunction with PTFE as sealing material, borosilicate glass is nowadays recognized as a material for plant construction. A complete modular system of individual components with suitable connecting pieces is available. Moreover, a variety of equipment has been developed for accomplishing various processes while paying due attention to the special material properties of the material glass. In combination with other materials, primarily in the field of heat exchangers and evaporators, numerous processes are now conducted without any difficulty in glass plant. In this range of processes, a special place is assumed by those which urgently require glass for corrosion reasons, such as chlorination or bromination reactions or concentration of acids, because specialized know-how is sometimes required.  相似文献   
22.
23.
Unconstrained Inverse Electrocardiography: Epicardial Potentials   总被引:2,自引:0,他引:2  
The inverse problem in electrocardiography is attacked via the development of a model appropriate for the computation of epicardial potentials from a knowledge of heart and torso geometry as well as surface potentials. The model takes the form of an integral equation of the first kind in which the kernel is interpreted as a Green's function. A theoretical investigation of system independence in the presence of error is developed, and two techniques for the theoretical consideration of system independence are examined. Application of these two techniques to concentric spherical systems indicates that spheres with ratios of inner-to-outer radii less than 0.5 contain less than twenty independent parameters in the presence of realistic noise levels. The number of independent parameters deteriorates rapidly as this ratio falls below 0.5. These results suggest that it is not feasible to determine epicardial potentials from torso potentials by using unconstrained solutions.  相似文献   
24.
25.
Silicon nitride is often used, when high fracture toughness and strength is needed. For a safe and economic structural design with this material, a prediction of its resistance against thermal and mechanical loads is important. The finite element method together with a continuum damage mechanics model allows for such calculations. The parameters of the suggested model have been adjusted to three-dimensional micromechanical finite element simulations, which include models for the microstructure, the thermoelasticity and the fracture. The material model is used for four-point bend test simulations. The results are compared to recent experiments.  相似文献   
26.
Positive Psychotherapy (PPT) is a therapeutic metatheory and approach that was developed in 1968 by Dr. Nossrat Peseschkian. His contribution to psychotherapy is not to be confused with what is being called PPT and is an outgrowth of Positive Psychology begun by Dr. Martin Seligman in the U.S. Peseschkian's approach to therapy is inherently and systematically integrative, along the lines of being cross-cultural, multidisciplinary, therapeutically, and psychologically intertheoretic. This article presents some basic premises of PPT: the use of stories; having a positive starting point; basic and actual capacities; five-stage therapeutic model; as well as mentioning other aspects of PPT and a case study. PPT is well suited to therapists advocating integrative psychotherapy as demonstrated by empirical research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
引言LTC(R)3855能够以上佳的准确度和效率来产生高电流轨,旨在满足当今最先时的网络、电信和服务器应用极其苛刻的要求.  相似文献   
28.
Color is a powerful visual cue in many computer vision applications such as image segmentation and object recognition. However, most of the existing color models depend on the imaging conditions that negatively affect the performance of the task at hand. Often, a reflection model (e.g., Lambertian or dichromatic reflectance) is used to derive color invariant models. However, this approach may be too restricted to model real-world scenes in which different reflectance mechanisms can hold simultaneously.  相似文献   
29.
Applications in industry often have grown and improved over many years. Since their performance demands increase, they also need to benefit from the availability of multi-core processors. However, a reimplementation from scratch and even a restructuring of these industrial applications is very expensive, often due to high certification efforts. Therefore, a strategy for a systematic parallelization of legacy code is needed. We present a parallelization approach for hard real-time systems, which ensures a high reusage of legacy code and preserves timing analysability. To show its applicability, we apply it on the core algorithm of an avionics application as well as on the control program of a large construction machine. We create models of the legacy programs showing the potential of parallelism, optimize them and change the source codes accordingly. The parallelized applications are placed on a predictable multi-core processor with up to 18 cores. For evaluation, we compare the worst case execution times and their speedups. Furthermore, we analyse limitations coming up at the parallelization process.  相似文献   
30.
Multimedia Tools and Applications - Predicting the interaction between two humans, when viewed as a part of video is one of the most challenging issues in the field of computer vision, due to its...  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