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   25328篇
  免费   3187篇
  国内免费   2493篇
电工技术   3981篇
技术理论   9篇
综合类   2532篇
化学工业   662篇
金属工艺   383篇
机械仪表   2459篇
建筑科学   1134篇
矿业工程   724篇
能源动力   362篇
轻工业   368篇
水利工程   440篇
石油天然气   306篇
武器工业   236篇
无线电   3505篇
一般工业技术   1959篇
冶金工业   451篇
原子能技术   23篇
自动化技术   11474篇
  2024年   96篇
  2023年   495篇
  2022年   949篇
  2021年   1122篇
  2020年   1189篇
  2019年   748篇
  2018年   719篇
  2017年   874篇
  2016年   954篇
  2015年   1073篇
  2014年   1881篇
  2013年   2040篇
  2012年   2141篇
  2011年   1941篇
  2010年   1483篇
  2009年   1504篇
  2008年   1599篇
  2007年   1795篇
  2006年   1445篇
  2005年   1351篇
  2004年   1098篇
  2003年   905篇
  2002年   751篇
  2001年   654篇
  2000年   485篇
  1999年   400篇
  1998年   268篇
  1997年   219篇
  1996年   153篇
  1995年   151篇
  1994年   125篇
  1993年   99篇
  1992年   70篇
  1991年   59篇
  1990年   39篇
  1989年   28篇
  1988年   13篇
  1987年   10篇
  1986年   17篇
  1985年   14篇
  1984年   14篇
  1983年   6篇
  1981年   5篇
  1980年   9篇
  1979年   2篇
  1978年   2篇
  1976年   3篇
  1975年   3篇
  1966年   1篇
  1965年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
A multi-agent architecture for dynamic scheduling of steel hot rolling   总被引:13,自引:0,他引:13  
Steel production is a complex process and finding coherent and effective schedules for the wide variety of production steps, in a dynamic environment, is a challenging task. In this paper, we propose a multi-agent architecture for integrated dynamic scheduling of the hot strip mill (HSM) and the continuous caster. The scheduling systems of these processes have very different objectives and constraints, and operate in an environment where there is a substantial quantity of real-time information concerning production failures and customer requests. Each process is assigned to an agent which independently, seeks an optimal dynamic schedule at a local level taking into account local objectives, real-time information and information received from other agents. Each agent can react to real-time events in order to fix any problems that occur. We focus here, particularly, on the HSM agent which uses a tabu search heuristic to create good predictive–reactive schedules quickly. The other agents simulate the production of the coil orders and the real-time events, which occur during the scheduling process. When real-time events occur on the HSM, the HSM agent might decide whether to repair the current schedule or reschedule from scratch. To address this problem, a range of schedule repair and complete rescheduling strategies are investigated and their performance is assessed with respect to measures of utility, stability and robustness, using an experimental simulation framework.  相似文献   
52.
介绍一个具有蓝牙通信功能的小型嵌入式系统--蓝牙智能车载卡的软件实现方案.描述了蓝牙智能车载卡在车辆信息化管理系统中的应用,介绍了蓝牙智能车载卡的系统设计方案,重点是软件设计和实现,分析了软件开发中遇到的一些问题及其解决方法,最后给出了实测结果,指出存在的不足之处和改进目标.  相似文献   
53.
54.
智能控制的理论和方法   总被引:11,自引:0,他引:11  
本文简要地回顾了智能控制的发展过程,讨论了智能控制的几个主要理论与方法,最后对智能控制的发展提出了作者的看法。  相似文献   
55.
本文介绍中日国际合作开发研究的A1型智能网(A1型IN)智能工作站(IW)主机的并行推理硬件结构的实验模型设计与实现,给出了一种并行推理硬件支持环境实现方案和该方案在实现中若干问题的解决方法。  相似文献   
56.
文章剖析了应用于智能网的计算机技术,阐述智能网和计算机技术的关系。  相似文献   
57.
Artificial retina chips which can simultaneously sense and process real world images are described. The comparison between artificial retinal systems and conventional image processing systems is described. Variable sensitivity photodetection, which is an essential technology for the artificial retina chips, is introduced in detail. The concept, structure, fundamental performance, operating principle, and processing functions for the fabricated artificial retinal chips are described. Applications including interactive games by gesture-input are also introduced. This work was presented, in part, at the International Symposium on Artificial Life and Robotics, Oita, Japan, February 18–20, 1996.  相似文献   
58.
压电类智能层合结构的力学和计算模型综述   总被引:2,自引:0,他引:2  
综述了压电类智能层合结构的力学和计算模型。基于大量国内外有关压电类智能层合结构的文献 ,根据各自采用的运动学假设、场变量的近似、压电层的表达法以及曲率和温度的影响 ,对压电层合结构的力学和计算模型进行了分类 ,阐述了各种理论的特点及一般形式。  相似文献   
59.
The even-flow harvest scheduling problem arises when the forestry agency has evolved into a rigid non-declining even-flow policy. In this paper, we investigate model formulation and solution strategies for the even-flow harvest scheduling problem. A multiple-objective linear programming problem is formulated for even-flow harvest scheduling problems with multiple-site classes and multiple periods. The aim of this problem is to simultaneously maximize a desired harvest-volume per hectare for each period of planning horizon and the total economic return. A block diagonal constraint structure, with many sets of network sub-problems and a set of coupling constraints, is identified in this linear programming problem. A longest path method for each of network sub-problems and a primal-dual steepest-edge algorithm for the entire problem are developed. The developed algorithm has been coded in Borland C++ and implemented on a personal computer. An illustrative example is used to display the detailed procedure for the developed algorithm and a real-world case study is used to show the trade-off between desired even-flow harvest volume policy and total economic return. Results show the potential benefits of this approach.  相似文献   
60.
Modeling video sources for real-time scheduling   总被引:1,自引:0,他引:1  
What is the impact of the autocorrelation of variable-bit-rate (VBR) sources on real-time scheduling algorithms? Our results show that the impact of long term, or interframe, autocorrelation is negligible, while the impact of short term, or intraframe, autocorrelation can be significant. Such results are essentially independent of the video coding scheme employed. To derive these results, video sequences are modeled as a collection of stationary subsequences called scenes. Within a scene, a statistical model is derived for both the sequence of frames and of slices. The model captures the distribution and the autocorrelation function of real-time video data. In previous work, the pseudoperiodicity of the slice level auto-correlation function made it difficult to develop a simple yet accurate model. We present a generalization of previous methods that can easily capture this pseudoperiodicity and is suited for modeling a greater variety of autocorrelation functions. By simply tuning a few parameters, the model reproduces the statistic behavior of sources with different types and levels of correlation on both the frame and the slice level.  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