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   6649篇
  免费   418篇
  国内免费   7篇
电工技术   71篇
综合类   10篇
化学工业   1966篇
金属工艺   83篇
机械仪表   137篇
建筑科学   240篇
矿业工程   11篇
能源动力   227篇
轻工业   902篇
水利工程   55篇
石油天然气   10篇
无线电   414篇
一般工业技术   1164篇
冶金工业   703篇
原子能技术   42篇
自动化技术   1039篇
  2024年   19篇
  2023年   106篇
  2022年   353篇
  2021年   437篇
  2020年   213篇
  2019年   208篇
  2018年   235篇
  2017年   215篇
  2016年   290篇
  2015年   205篇
  2014年   312篇
  2013年   403篇
  2012年   396篇
  2011年   511篇
  2010年   334篇
  2009年   296篇
  2008年   355篇
  2007年   279篇
  2006年   218篇
  2005年   194篇
  2004年   152篇
  2003年   144篇
  2002年   106篇
  2001年   80篇
  2000年   61篇
  1999年   76篇
  1998年   139篇
  1997年   84篇
  1996年   83篇
  1995年   48篇
  1994年   45篇
  1993年   38篇
  1992年   42篇
  1991年   31篇
  1990年   25篇
  1989年   30篇
  1988年   27篇
  1987年   33篇
  1986年   26篇
  1985年   30篇
  1984年   24篇
  1983年   18篇
  1982年   17篇
  1981年   14篇
  1980年   13篇
  1979年   14篇
  1977年   10篇
  1976年   21篇
  1973年   7篇
  1968年   8篇
排序方式: 共有7074条查询结果,搜索用时 0 毫秒
91.
92.
We present a Peer-to-Peer network design which aims to support business activities conducted through a network of collaborations that generate value in different, mutually beneficial, ways for the participating organisations. The temporary virtual networks formed by long-term business transactions that involve the execution of multiple services from different providers are used as the building block of the underlying scale-free business network. We show how these local interactions, which are not governed by a single organisation, give rise to a fully distributed P2P architecture that reflects the dynamics of business activities. The design is based on dynamically formed permanent clusters of nodes, the so-called Virtual Super Peers (VSPs), and this results in a topology that is highly resilient to certain types of failure (and attacks). Furthermore, the proposed P2P architecture is capable of reconfiguring itself to adapt to the usage that is being made of it and respond to global failures of conceptual hubs. This fosters an environment where business communities can evolve to meet emerging business opportunities and achieve sustainable growth within a digital ecosystem.  相似文献   
93.
This paper describes the development of a system for measuring surface coordinates (commonly known as "shape measurements") which is able to give the temporal evolution of the position of the tire sidewall in transient conditions (such as during braking, when there are potholes or when the road surface is uneven) which may or may not be reproducible. The system is based on the well-known technique of projecting and observing structured light using a digital camera with an optical axis which is slanted with respect to the axis of the projector. The transient nature of the phenomenon has led to the development of specific innovative solutions as regards image processing algorithms. This paper briefly describes the components which make up the measuring system and presents the results of the measurements carried out on the drum bench. It then analyses the performance of the measuring system and the sources of uncertainty which led to the development of the system for a specific dynamic application: impact with an obstacle (cleat test). The measuring system guaranteed a measurement uncertainty of 0.28 mm along the Z axis (the axial direction of the tire) with a measurement range of 250(X) x 80(Y) x 25(Z) mm(3), with the tire rolling at a speed of up to 30 km/h.  相似文献   
94.
We have developed a simple and accurate method for calibrating the amplitude of vibration of quartz tuning fork sensors commonly used in atomic force- and near field optical-microscopy. Unlike interferometric methods, which require a complex optical setup, the method we present requires only a simple measurement of the electro-mechanical properties of the tuning-fork oscillator and can be performed in a matter of minutes without disturbing the experimental setup. Comparison with interferometric methods shows that an accuracy of better than few percent can be routinely achieved.  相似文献   
95.
96.
In this paper we discuss the potentials of a new Bayesian inference tool, called the Gibbs sampler, for the analysis of the censored regression or Tobit model. Tobit models have a wide range of applications in empirical sciences, like econometrics and biometrics. The estimation results of the simple Tobit model will be compared to a hierarchical Tobit model, and the Gibbs sampling approach to the related classical algorithm of expectation-maximisation (EM). The underlying botanical example of this paper is concerned with the censoring mechanism in plant reproduction and proposes the Bayesian Tobit model for the growth relationship between the reproductive part and the rest of the plant.  相似文献   
97.
Building brains for bodies   总被引:10,自引:2,他引:8  
We describe a project to capitalize on newly available levels of computational resources in order to understand human cognition. We are building an integrated physical system including vision, sound input and output, and dextrous manipulation, all controlled by a continuously operating large scale parallel MIMD computer. The resulting system will learn to think by building on its bodily experiences to accomplish progressively more abstract tasks. Past experience suggests that in attempting to build such an integrated system we will have to fundamentally change the way artificial intelligence, cognitive science, linguistics, and philosophy think about the organization of intelligence. We expect to be able to better reconcile the theories that will be developed with current work in neuroscience.  相似文献   
98.
Software and Systems Modeling - The Internet of things has been adopted in several sectors both influencing how people work and enhancing organizations’ business processes. This resulted in...  相似文献   
99.
Knowledge and Information Systems - Pattern mining is a fundamental data mining task with applications in several domains. In this work, we consider the scenario in which we have a sequence of...  相似文献   
100.
Journal of Intelligent Information Systems - Conversational Recommender Systems have received widespread attention in both research and practice. They assist people in finding relevant and...  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