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   434篇
  免费   25篇
电工技术   2篇
化学工业   81篇
金属工艺   9篇
机械仪表   3篇
建筑科学   13篇
矿业工程   1篇
能源动力   5篇
轻工业   88篇
水利工程   1篇
石油天然气   2篇
无线电   49篇
一般工业技术   47篇
冶金工业   64篇
原子能技术   1篇
自动化技术   93篇
  2023年   3篇
  2022年   11篇
  2021年   10篇
  2020年   9篇
  2019年   8篇
  2018年   17篇
  2017年   11篇
  2016年   20篇
  2015年   11篇
  2014年   21篇
  2013年   31篇
  2012年   31篇
  2011年   35篇
  2010年   16篇
  2009年   20篇
  2008年   19篇
  2007年   25篇
  2006年   16篇
  2005年   17篇
  2004年   10篇
  2003年   11篇
  2002年   7篇
  2001年   7篇
  2000年   5篇
  1999年   4篇
  1998年   24篇
  1997年   13篇
  1996年   8篇
  1995年   6篇
  1994年   3篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1990年   3篇
  1989年   4篇
  1988年   3篇
  1984年   1篇
  1983年   1篇
  1981年   4篇
  1980年   1篇
  1978年   3篇
  1977年   1篇
  1976年   5篇
排序方式: 共有459条查询结果,搜索用时 15 毫秒
1.
Telecommunication Systems - The Software-Defined Networking (SDN) architecture decouples the control plane from the data plane, but it does not explicitly state where the control should be located....  相似文献   
2.
We have studied the optical power losses due to multiple curvatures in polymethylmetacrylate (PMMA) plastic optical fibers (POFs) of different numerical apertures (NAs) and attenuation. The fibers were tested for several configurations in order to assess the influence of different types of curved-to-straight fiber transitions in the amount of power radiation. We found that losses are below the standards for all tested fiber types, and thus, they are a suitable choice for local area network (LAN) applications. In addition, our results revealed the presence of modal interactions as confirmed using an experimental procedure to estimate the mode coupling strength for the same fibers.  相似文献   
3.
Adiabatic switching is a technique to design low-power digital IC's. Fully adiabatic logics have expensive silicon area requirements. To solve this drawback, a quasi-adiabatic ternary logic is proposed. Its basis is presented, and to validate its performance, a 5×5 ternary digit multiplier is designed and implemented in a 0.7-μm CMOS technology. Results show a satisfactory power saving with respect to conventional and other quasi-adiabatic binary multipliers, and a decrease of the area needed with respect to a fully adiabatic binary one  相似文献   
4.
5.
6.
This article describes a novel approach to model the quality of experience (QoE) of users in mobile environments. The context-aware and ratings interaction model (CARIM) addresses the open questions of how to quantify user experiences from the analysis of interaction in mobile scenarios, and how to compare different QoE records to each other. A set of parameters are used to dynamically describe the interaction between the user and the system, the context in which it is performed and the perceived quality of users. CARIM structures these parameters into a uniform representation, supporting the dynamic analysis of interaction to determine QoE of users and enabling the comparison between different interaction records. Its run-time nature allows applications to make context- and QoE-based decisions in real time to adapt themselves, and thus provide a better experience to users. As a result, CARIM provides unified criteria for the inference and analysis of QoE in mobile scenarios. Its design and implementation can be integrated (and easily extended if needed) into many different development environments. An experiment with real users comparing two different interaction designs and validating user behavior hypotheses proved the effectiveness of applying CARIM for the assessment of QoE in mobile applications.  相似文献   
7.
Virtual Reality - Stroke rehabilitation suffers from low levels of patient engagement, impeding recovery. Virtual rehabilitation (VR) approaches can improve patient outcomes; however, there is...  相似文献   
8.
9.
Quantitative Evaluation of Register Pressure on Software Pipelined Loops   总被引:3,自引:0,他引:3  
Software Pipelining is a loop scheduling technique that extracts loop parallelism by overlapping the execution of several consecutive iterations. One of the drawbacks of software pipelining is its high register requirements, which increase with the number of functional units and their degree of pipelining. This paper analyzes the register requirements of software pipelined loops. It also evaluates the effects on performance of the addition of spill code. Spill code is needed when the number of registers required by the software pipelined loop is larger than the number of registers of the target machine. This spill code increases memory traffic and can reduce performance. Finally, compilers can apply transformations in order to reduce the number of memory accesses and increase functional unit utilization. The paper also evaluates the negative effect on register requirements that some of these transformations might produce on loops.  相似文献   
10.
Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation.  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