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   7964篇
  免费   1104篇
  国内免费   1334篇
电工技术   66篇
综合类   310篇
化学工业   273篇
金属工艺   58篇
机械仪表   104篇
建筑科学   76篇
矿业工程   20篇
能源动力   126篇
轻工业   280篇
水利工程   19篇
石油天然气   22篇
武器工业   21篇
无线电   1116篇
一般工业技术   247篇
冶金工业   18篇
原子能技术   63篇
自动化技术   7583篇
  2024年   77篇
  2023年   347篇
  2022年   301篇
  2021年   457篇
  2020年   336篇
  2019年   259篇
  2018年   305篇
  2017年   600篇
  2016年   505篇
  2015年   514篇
  2014年   798篇
  2013年   600篇
  2012年   695篇
  2011年   682篇
  2010年   570篇
  2009年   641篇
  2008年   499篇
  2007年   592篇
  2006年   565篇
  2005年   317篇
  2004年   88篇
  2003年   126篇
  2002年   98篇
  2001年   79篇
  2000年   108篇
  1999年   78篇
  1998年   49篇
  1997年   27篇
  1996年   24篇
  1995年   6篇
  1994年   8篇
  1993年   8篇
  1992年   8篇
  1991年   8篇
  1990年   3篇
  1989年   2篇
  1988年   5篇
  1987年   1篇
  1986年   5篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1981年   3篇
  1980年   1篇
  1978年   1篇
  1975年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
In the present era of machines and edge-cutting technologies, still document frauds persist. They are done intuitively by using almost identical inks, that it becomes challenging to detect them—this demands an approach that efficiently investigates the document and leaves it intact. Hyperspectral imaging is one such a type of approach that captures the images from hundreds to thousands of spectral bands and analyzes the images through their spectral and spatial features, which is not possible by conventional imaging. Deep learning is an edge-cutting technology known for solving critical problems in various domains. Utilizing supervised learning imposes constraints on its usage in real scenarios, as the inks used in forgery are not known prior. Therefore, it is beneficial to use unsupervised learning. An unsupervised feature extraction through a Convolutional Autoencoder (CAE) followed by Logistic Regression (LR) for classification is proposed (CAE-LR). Feature extraction is evolved around spectral bands, spatial patches, and spectral-spatial patches. We inspected the impact of spectral, spatial, and spectral-spatial features by mixing inks in equal and unequal proportion using CAE-LR on the UWA writing ink hyperspectral images dataset for blue and black inks. Hyperspectral images are captured at multiple correlated spectral bands, resulting in information redundancy handled by restoring certain principal components. The proposed approach is compared with eight state-of-art approaches used by the researchers. The results depicted that by using the combination of spectral and spatial patches, the classification accuracy enhanced by 4.85% for black inks and 0.13% for blue inks compared to state-of-art results. In the present scenario, the primary area concern is to identify and detect the almost similar inks used in document forgery, are efficiently managed by the proposed approach.  相似文献   
2.
3.
Events     
  相似文献   
4.
Mobile Networks and Applications - In Wireless Sensor Networks (WSNs), energy-efficient routing is required to conserve the scarce resources of these networks. Various energy-efficient routing...  相似文献   
5.
Conventional hydraulic fracturing fails to develop low permeability reservoirs of fossil hydrogen energy that are not located in the direction of maximum principal in-situ stress. A new technology of fracture propagation guided by radial holes is proposed, which can realize directional propagation of hydraulic fracture along radial holes in fossil hydrogen energy development. In order to verify this new technology, a model of radial holes combined with hydraulic fracturing is established by the ABAQUS extended finite element method. Simulation results show that radial holes play a guiding role in fractures propagation. The influence extent of seven factors on the directional propagation of hydraulic fracture is listed as follows (from strong to weak): azimuth of radial holes > horizontal in-situ stress difference of fossil hydrogen reservoir > injection rate of fracturing fluid > Young's modulus of rock > permeability of fossil hydrogen reservoir > Poisson ratio of rock > viscosity of fracturing fluid. True tri-axial experiment is carried out to verify the accuracy of numerical simulation, and the result is consistent with numerical model, which indicates that numerical simulation is reliable.  相似文献   
6.
Adoption of agile values and principles and transformation of organizations towards agility are not easy and straightforward. Misinterpretation of agile principles and values, and adoption of partial solutions with few agile practices instead of holistic approaches prevent organizations to obtain full benefits of agile methods. We developed the Software Agility Assessment Reference Model (AgilityMod) for the appraisal of software projects from agility perspective and to provide guidance on specifying gaps on the road towards agility (agile maturity). The meta-model of AgilityMod was defined in relation with the ISO/IEC 15504-Process Assessment Model. AgilityMod was developed in an iterative and incremental manner by running successive case studies and getting opinions of experts for the evaluation and improvement of the Model. The multiple case study that we present here in detail included the implementation of the Model in eight software development companies. The results of this case study were evaluated by the case study participants. According to the significant majority of the case study participants, AgilityMod achieves its purpose.  相似文献   
7.
8.
9.
10.
The Journal of Supercomputing - As the distributed computing systems have been widely used in many research and industrial areas, the problem of allocating tasks to available processors in the...  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