全文获取类型
收费全文 | 21428篇 |
免费 | 2199篇 |
国内免费 | 1796篇 |
专业分类
电工技术 | 1313篇 |
技术理论 | 1篇 |
综合类 | 2457篇 |
化学工业 | 320篇 |
金属工艺 | 319篇 |
机械仪表 | 998篇 |
建筑科学 | 591篇 |
矿业工程 | 515篇 |
能源动力 | 141篇 |
轻工业 | 274篇 |
水利工程 | 300篇 |
石油天然气 | 313篇 |
武器工业 | 130篇 |
无线电 | 4718篇 |
一般工业技术 | 587篇 |
冶金工业 | 328篇 |
原子能技术 | 100篇 |
自动化技术 | 12018篇 |
出版年
2024年 | 64篇 |
2023年 | 139篇 |
2022年 | 308篇 |
2021年 | 361篇 |
2020年 | 402篇 |
2019年 | 257篇 |
2018年 | 300篇 |
2017年 | 416篇 |
2016年 | 474篇 |
2015年 | 683篇 |
2014年 | 1309篇 |
2013年 | 1155篇 |
2012年 | 1636篇 |
2011年 | 1730篇 |
2010年 | 1384篇 |
2009年 | 1333篇 |
2008年 | 1652篇 |
2007年 | 1812篇 |
2006年 | 1565篇 |
2005年 | 1606篇 |
2004年 | 1390篇 |
2003年 | 1248篇 |
2002年 | 931篇 |
2001年 | 801篇 |
2000年 | 604篇 |
1999年 | 412篇 |
1998年 | 285篇 |
1997年 | 236篇 |
1996年 | 193篇 |
1995年 | 168篇 |
1994年 | 132篇 |
1993年 | 103篇 |
1992年 | 81篇 |
1991年 | 59篇 |
1990年 | 38篇 |
1989年 | 36篇 |
1988年 | 16篇 |
1987年 | 18篇 |
1986年 | 9篇 |
1985年 | 20篇 |
1984年 | 17篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
This paper presents a novel No-Reference Video Quality Assessment (NR-VQA) model that utilizes proposed 3D steerable wavelet transform-based Natural Video Statistics (NVS) features as well as human perceptual features. Additionally, we proposed a novel two-stage regression scheme that significantly improves the overall performance of quality estimation. In the first stage, transform-based NVS and human perceptual features are separately passed through the proposed hybrid regression scheme: Support Vector Regression (SVR) followed by Polynomial curve fitting. The two visual quality scores predicted from the first stage are then used as features for the similar second stage. This predicts the final quality scores of distorted videos by achieving score level fusion. Extensive experiments were conducted using five authentic and four synthetic distortion databases. Experimental results demonstrate that the proposed method outperforms other published state-of-the-art benchmark methods on synthetic distortion databases and is among the top performers on authentic distortion databases. The source code is available at https://github.com/anishVNIT/two-stage-vqa. 相似文献
2.
3.
In this paper we combine video compression and modern image processing methods. We construct novel iterative filter methods for prediction signals based on Partial Differential Equation (PDE) based methods. The mathematical framework of the employed diffusion filter class is given and some desirable properties are stated. In particular, two types of diffusion filters are constructed: a uniform diffusion filter using a fixed filter mask and a signal adaptive diffusion filter that incorporates the structures of the underlying prediction signal. The latter has the advantage of not attenuating existing edges while the uniform filter is less complex. The filters are embedded into a software based on HEVC with additional QTBT (Quadtree plus Binary Tree) and MTT (Multi-Type-Tree) block structure. In this setting, several measures to reduce the coding complexity of the tool are introduced, discussed and tested thoroughly. The coding complexity is reduced by up to 70% while maintaining over 80% of the gain. Overall, the diffusion filter method achieves average bitrate savings of 2.27% for Random Access having an average encoder runtime complexity of 119% and 117% decoder runtime complexity. For individual test sequences, results of 7.36% for Random Access are accomplished. 相似文献
4.
Private information retrieval(PIR) is an important privacy protection issue of secure multi-party computation, but the PIR protocols based on classical cryptography are vulnerable because of new technologies,such as quantum computing and cloud computing. The quantum private queries(QPQ) protocols available, however, has a high complexity and is inefficient in the face of large database. This paper, based on the QKD technology which is mature now, proposes a novel QPQ protocol utilizing the key dilution and auxiliary parameter. Only N quits are required to be sent in the quantum channel to generate the raw key, then the straight k bits in the raw key are added bitwise to dilute the raw key, and a final key is consequently obtained to encrypt the database. By flexible adjusting of auxiliary parameters θ and k, privacy is secured and the query success ratio is improved. Feasibility and performance analyses indicate that the protocol has a high success ratio in first-trial query and is easy to implement, and that the communication complexity of O(N) is achieved. 相似文献
5.
6.
近年来深度学习迅猛发展,颠覆了语音识别、图像分类、文本理解等领域的算法设计思路。深度学习因其具备强大的特征提取能力,在图像识别领域的成绩尤为突出。然而深度学习与视频监控领域的结合并不多,由于深度模型具有多层网络结构,算法复杂度大,训练和更新模型时比较耗时,很难满足实时性要求。回顾了深度学习的发展史,介绍了最近10年来国内外深度学习主要模型,论述了基于深度学习的目标跟踪算法,指出了各算法的优缺点,最后对当前该领域存在的问题和发展前景进行了总结和展望。 相似文献
7.
人像智能分析指的是对视频或录像中的人像进行结构化和可视化分析,对目标人物进行性别、年龄、发型等特征的智能识别,这项技术在视频侦查中有极高的应用价值。人像识别早期的算法是通过人工提取特征,通过学习低级视觉特征来针对不同属性进行分类学习,这种基于传统方法的模型表现常常不尽如人意。在计算机视觉领域,通过海量图像数据学习的神经网络比传统方法有更丰富的信息量和特征可以被提取。文章尝试通过深度学习技术训练神经网络模型对行人进行检测和识别,对于衣着不同的行人进行智能识别,具有更好的鲁棒性,提升了视频人像识别的准确率,拓展了人工智能技术在身份识别领域的应用。 相似文献
8.
9.
10.
在目前数据爆炸、信息匮乏的情况下,需要利用数据仓库系统集成1个或多个独立传统数据库数据,通过分析海量数据发现市场潜在规律,获取商业信息以支持商业决策,这将是广电未来的制胜武器。 相似文献