全文获取类型
收费全文 | 32524篇 |
免费 | 4155篇 |
国内免费 | 2421篇 |
专业分类
电工技术 | 980篇 |
综合类 | 1175篇 |
化学工业 | 4882篇 |
金属工艺 | 1915篇 |
机械仪表 | 1645篇 |
建筑科学 | 1035篇 |
矿业工程 | 269篇 |
能源动力 | 1922篇 |
轻工业 | 2601篇 |
水利工程 | 257篇 |
石油天然气 | 301篇 |
武器工业 | 1866篇 |
无线电 | 4775篇 |
一般工业技术 | 4813篇 |
冶金工业 | 551篇 |
原子能技术 | 148篇 |
自动化技术 | 9965篇 |
出版年
2024年 | 244篇 |
2023年 | 1295篇 |
2022年 | 1466篇 |
2021年 | 1522篇 |
2020年 | 1796篇 |
2019年 | 1447篇 |
2018年 | 1425篇 |
2017年 | 2052篇 |
2016年 | 2239篇 |
2015年 | 2129篇 |
2014年 | 2574篇 |
2013年 | 2562篇 |
2012年 | 3025篇 |
2011年 | 2914篇 |
2010年 | 1802篇 |
2009年 | 1989篇 |
2008年 | 872篇 |
2007年 | 1802篇 |
2006年 | 1524篇 |
2005年 | 767篇 |
2004年 | 325篇 |
2003年 | 322篇 |
2002年 | 373篇 |
2001年 | 354篇 |
2000年 | 301篇 |
1999年 | 332篇 |
1998年 | 161篇 |
1997年 | 111篇 |
1996年 | 125篇 |
1995年 | 108篇 |
1994年 | 77篇 |
1993年 | 70篇 |
1992年 | 55篇 |
1991年 | 55篇 |
1990年 | 50篇 |
1989年 | 47篇 |
1988年 | 95篇 |
1987年 | 255篇 |
1986年 | 191篇 |
1985年 | 63篇 |
1984年 | 30篇 |
1983年 | 16篇 |
1982年 | 28篇 |
1981年 | 19篇 |
1980年 | 13篇 |
1979年 | 34篇 |
1978年 | 21篇 |
1977年 | 8篇 |
1976年 | 11篇 |
1951年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
以企业员工信息管理系统为例,论述该系统的设计及其实现,研究J2EE、Struts、Hibernate和Spring等主流技术在实际开发中的应用。结果表明,SSH技术架构在构建复杂业务系统中提高了开发效率和系统的可维护性,同时增强了系统的可扩展性。 相似文献
32.
33.
34.
《Displays》2021
The three-dimensional virtual scene can provide users with a visual three-dimensional virtual environment, with various multimedia channels such as sound, video, force feedback equipment, etc., to bring users a completely immersive interactive experience. This paper introduces 3D imaging and virtual reality technology in the film and television industry cloud exhibition, and develops a virtual display platform. First of all, this paper divides the registration into two processes: camera calibration and joint calibration of the camera and laser scanner based on the calibration results. Camera calibration can determine the plane model of the calibration board in the camera coordinate system, and the joint calibration uses the RANSAC algorithm to extract the point cloud of the plane model of the calibration board, and then optimizes the distance between the points in the plane model point cloud and the corresponding plane in the camera coordinate system Find the optimal transformation between the two sets of data, and then calculate the registration relationship between the point cloud and the image. Secondly, this article conducts a demand analysis of the film and television industry cloud exhibition platform based on virtual reality technology, including the business goals set by the platform, platform system analysis, overall design, and system operating environment and configuration requirements. This model provides a feasible solution for the visual interaction of the cloud exhibition design of the film and television industry. 相似文献
35.
Effective tool wear monitoring (TWM) is essential for accurately assessing the degree of tool wear and for timely preventive maintenance. Existing data-driven monitoring methods mainly rely on complex feature engineering, which reduces the monitoring efficiency. This paper proposes a novel TWM model based on a parallel residual and stacked bidirectional long short-term memory (PRes–SBiLSTM) network. First, a parallel residual network (PResNet) is used to extract the multi-scale local features of sensor signals adaptively. Subsequently, a stacked bidirectional long short-term memory (SBiLSTM) network is used to obtain the time-series features related to the tool wear characteristics. Finally, the predicted tool wear value is outputted through a fully connected network. A smoothing correction method is applied to improve the prediction accuracy. The proposed model is experimentally verified to have a high prediction accuracy without sacrificing its generalization ability. A TWM system framework based on the PRes–SBiLSTM network is proposed, which has a certain reference value for TWM in actual industrial environments. 相似文献
36.
In order to guarantee security and privacy of sensitive data, attribute-based keyword search (ABKS) enables data owners to upload their encrypted data to cloud servers, and authorizes intended data users to retrieve it. Meanwhile, ABKS outsources heavy search work to cloud servers, which makes ABKS adaptive to mobile computing environment. However, as cloud servers can both generate keyword ciphertexts and run search algorithm, the existing most ABKS schemes are vulnerable to keyword guessing attack. In this paper, we show the fundamental cause that the existing ABKS schemes do not resist keyword guessing attack is any entity can generate keyword ciphertext. To solve the above problem, in the phase of keyword ciphertext generation, we use private key of data owner to sign keyword prior to generating keyword ciphertext. Therefore, any other entity does not forge keyword ciphertext, which can resist keyword guessing attack. We give the formal definition and security model of attributed-based keyword search secure against keyword guessing attack (ABKS-SKGA). Furthermore, we provide an ABKS-SKGA scheme. The ABKS-SKGA scheme is proved secure against chosen-plaintext attack (CPA). Performance analysis shows that the proposed scheme is practical. 相似文献
37.
38.
Nanehkaran Y. A. Zhang Defu Salimi S. Chen Junde Tian Yuan Al-Nabhan Najla 《The Journal of supercomputing》2021,77(4):3193-3222
The Journal of Supercomputing - Handwriting recognition remains a challenge in the machine vision field, especially in optical character recognition (OCR). The OCR has various applications such as... 相似文献
39.
Gu Min Gu Yanhui Luo Weilan Xu Guandong Yang Zhenglu Zhou Junsheng Qu Weiguang 《Neural computing & applications》2021,33(11):6009-6025
Neural Computing and Applications - Semantic understanding is an essential research issue for many applications, such as social network analysis, collective intelligence and content computing,... 相似文献
40.