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   2583篇
  免费   179篇
  国内免费   19篇
电工技术   47篇
综合类   6篇
化学工业   644篇
金属工艺   37篇
机械仪表   90篇
建筑科学   74篇
矿业工程   2篇
能源动力   210篇
轻工业   242篇
水利工程   18篇
石油天然气   41篇
无线电   274篇
一般工业技术   522篇
冶金工业   126篇
原子能技术   20篇
自动化技术   428篇
  2024年   4篇
  2023年   86篇
  2022年   145篇
  2021年   186篇
  2020年   142篇
  2019年   148篇
  2018年   182篇
  2017年   132篇
  2016年   171篇
  2015年   108篇
  2014年   166篇
  2013年   228篇
  2012年   143篇
  2011年   133篇
  2010年   111篇
  2009年   98篇
  2008年   82篇
  2007年   59篇
  2006年   57篇
  2005年   37篇
  2004年   31篇
  2003年   34篇
  2002年   30篇
  2001年   22篇
  2000年   12篇
  1999年   15篇
  1998年   42篇
  1997年   12篇
  1996年   28篇
  1995年   18篇
  1994年   18篇
  1993年   19篇
  1992年   7篇
  1991年   8篇
  1990年   5篇
  1988年   6篇
  1987年   6篇
  1986年   8篇
  1985年   5篇
  1984年   8篇
  1983年   5篇
  1982年   2篇
  1981年   2篇
  1980年   2篇
  1979年   5篇
  1978年   2篇
  1977年   2篇
  1976年   2篇
  1973年   1篇
  1959年   4篇
排序方式: 共有2781条查询结果,搜索用时 78 毫秒
31.
32.
33.
34.
35.
Feature selection and sentiment analysis are two common studies that are currently being conducted; consistent with the advancements in computing and growing the use of social media. High dimensional or large feature sets is a key issue in sentiment analysis as it can decrease the accuracy of sentiment classification and make it difficult to obtain the optimal subset of the features. Furthermore, most reviews from social media carry a lot of noise and irrelevant information. Therefore, this study proposes a new text-feature selection method that uses a combination of rough set theory (RST) and teaching-learning based optimization (TLBO), which is known as RSTLBO. The framework to develop the proposed RSTLBO includes numerous stages: (1) acquiring the standard datasets (user reviews of six major U.S. airlines) which are used to validate search result feature selection methods, (2) pre-processing of the dataset using text processing methods. This involves applying text processing methods from natural language processing techniques, combined with linguistic processing techniques to produce high classification results, (3) employing the RSTLBO method, and (4) using the selected features from the previous process for sentiment classification using the Support Vector Machine (SVM) technique. Results show an improvement in sentiment analysis when combining natural language processing with linguistic processing for text processing. More importantly, the proposed RSTLBO feature selection algorithm is able to produce an improved sentiment analysis.  相似文献   
36.
Multimedia Tools and Applications - Face detection by low-resolution image (LR) is one of the key aspects of Human-Computer Interaction(HCI). Due to the LR image, which has changes in pose,...  相似文献   
37.
38.
Engineering with Computers - Air overpressure (AOp) is one of the most important undesirable effects induced by blasting operations in the mining or tunneling projects. Hence, the present precise...  相似文献   
39.
40.

Wireless body area network (WBAN) has witnessed significant attentions in the healthcare domain using biomedical sensor-based monitoring of heterogeneous nature of vital signs of a patient’s body. The design of frequency band, MAC superframe structure, and slots allocation to the heterogeneous nature of the patient’s packets have become the challenging problems in WBAN due to the diverse QoS requirements. In this context, this paper proposes an Energy Efficient Traffic Prioritization for Medium Access Control (EETP-MAC) protocol, which provides sufficient slots with higher bandwidth and guard bands to avoid channels interference causing longer delay. Specifically, the design of EETP-MAC is broadly divided in to four folds. Firstly, patient data traffic prioritization is presented with broad categorization including Non-Constrained Data (NCD), Delay-Constrained Data (DCD), Reliability-Constrained Data (RCD) and Critical Data (CD). Secondly, a modified superframe structure design is proposed for effectively handling the traffic prioritization. Thirdly, threshold based slot allocation technique is developed to reduce contention by effectively quantifying criticality on patient data. Forth, an energy efficient frame design is presented focusing on beacon interval, superframe duration, and packet size and inactive period. Simulations are performed to comparatively evaluate the performance of the proposed EETP-MAC with the state-of-the-art MAC protocols. The comparative evaluation attests the benefit of EETP-MAC in terms of efficient slot allocation resulting in lower delay and energy consumption.

  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