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   95358篇
  免费   1441篇
  国内免费   458篇
电工技术   1012篇
综合类   2331篇
化学工业   13403篇
金属工艺   5090篇
机械仪表   3352篇
建筑科学   2370篇
矿业工程   629篇
能源动力   1793篇
轻工业   4694篇
水利工程   1418篇
石油天然气   423篇
无线电   10734篇
一般工业技术   18865篇
冶金工业   4119篇
原子能技术   442篇
自动化技术   26582篇
  2023年   178篇
  2022年   426篇
  2021年   499篇
  2020年   417篇
  2019年   416篇
  2018年   14818篇
  2017年   13708篇
  2016年   10354篇
  2015年   879篇
  2014年   669篇
  2013年   1086篇
  2012年   3623篇
  2011年   10008篇
  2010年   8745篇
  2009年   6037篇
  2008年   7212篇
  2007年   8120篇
  2006年   449篇
  2005年   1456篇
  2004年   1360篇
  2003年   1379篇
  2002年   714篇
  2001年   229篇
  2000年   306篇
  1999年   201篇
  1998年   390篇
  1997年   246篇
  1996年   285篇
  1995年   232篇
  1994年   197篇
  1993年   181篇
  1992年   155篇
  1991年   171篇
  1990年   114篇
  1989年   102篇
  1988年   131篇
  1987年   107篇
  1986年   88篇
  1985年   116篇
  1984年   95篇
  1983年   111篇
  1982年   100篇
  1981年   89篇
  1980年   76篇
  1979年   51篇
  1977年   57篇
  1976年   77篇
  1968年   51篇
  1955年   63篇
  1954年   68篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Journal of Materials Science: Materials in Electronics - Pure PVDF has higher breakdown strength but low dielectric and ferroelectric properties. Thus, we synthesized the LaFeO3 and GdFeO3...  相似文献   
2.
Journal of Materials Science - La0.7Pb0.3MnO3(LPMO) nanoparticles (NPs) were prepared by sol–gel auto-combustion method. These were embedded in P(VDF-TrFE) to form (0–3) nanocomposite...  相似文献   
3.
Journal of Materials Science: Materials in Electronics - Tuning the band gap of ferroelectric materials to visible region without reducing the polarization can provide an ideal photovoltaic...  相似文献   
4.

ResearchGate has emerged as a popular professional network for scientists and researchers in a very short span. Similar to Google Scholar, the ResearchGate indexing uses an automatic crawling algorithm that extracts bibliographic data, citations, and other information about scholarly articles from various sources. However, it has been observed that the two platforms often show different publication and citation data for the same institutions, journals, and authors. While several previous studies analysed different aspects of ResearchGate and Google Scholar, the quantum of differences in publications, citations, and metrics between the two and the probable reasons for the same are not explored much. This article, therefore, attempts to bridge this research gap by analysing and measuring the differences in publications, citations, and different metrics of the two platforms for a large data set of highly cited authors. The results indicate that there are significantly high differences in publications and citations for the same authors captured by the two platforms, with Google Scholar having higher counts for a vast majority of the cases. The different metrics computed by the two platforms also differ in their values, showing different degrees of correlation. The coverage policy, indexing errors, author attribution mechanism, and strategy to deal with predatory publishing are found to be the main probable reasons for the differences in the two platforms.

  相似文献   
5.
Rapid digestion and absorption of carbohydrates have become a health issue (high glycaemic index, GI), which can be a matter of greater concern when consumed in large quantities. Depending upon the influence of carbohydrates on the blood sugar levels, GI classifies carbohydrates (on a scale of 100) as low (<55), medium (55–70) and high (>70) GI foods. Among the pseudocereals, chia seed possesses relatively lower GI (28.53), as compared to buckwheat (52.35), amaranth (47.65) and quinoa (61.50). Consumers now prefer foods with a high GI over the ones with low GI to prevent various metabolic alterations. Celiac disease is a lifelong disorder prevalent worldwide and can only be controlled by following a strict lifelong gluten-free diet. Therefore, pseudocereals could be a potential alternate for low GI food and developing gluten-free food products, including bread, cookies, noodles and pasta. This review synthesises the recently published literatures on pseudocereals as a lowering GI and healthy food option. This review also gives insights into developing pseudocereals as a potential and novel ingredient for gluten-free food applications and the latest research conducted worldwide.  相似文献   
6.
7.
8.

Explosive growth of big data demands efficient and fast algorithms for nearest neighbor search. Deep learning-based hashing methods have proved their efficacy to learn advanced hash functions that suit the desired goal of nearest neighbor search in large image-based data-sets. In this work, we present a comprehensive review of different deep learning-based supervised hashing methods particularly for image data-sets suggested by various researchers till date to generate advanced hash functions. We categorize prior works into a five-tier taxonomy based on: (i) the design of network architecture, (ii) training strategy based on nature of data-set, (iii) the type of loss function, (iv) the similarity measure and, (v) the nature of quantization. Further, different data-sets used in prior works are reported and compared based on various challenges in the characteristics of images that are part of the data-sets. Lastly, different future directions such as incremental hashing, cross-modality hashing and guidelines to improve design of hash functions are discussed. Based on our comparative review, it has been observed that generative adversarial networks-based hashing models outperform other methods. This is due to the fact that they leverage more data in the form of both real world and synthetically generated data. Furthermore, it has been perceived that triplet-loss-based loss functions learn better discriminative representations by pushing similar patterns together and dis-similar patterns away from each other. This study and its observations shall be useful for the researchers and practitioners working in this emerging research field.

  相似文献   
9.
Multimedia Tools and Applications - The video surveillance activity generates a vast amount of data, which can be processed to detect miscreants. The task of identifying and recognizing an object...  相似文献   
10.
Wireless Personal Communications - For the optimal performance of wireless sensor networks in different areas of applications needs to maximize the coverage area of sensor nodes. The coverage of...  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