全文获取类型
收费全文 | 130643篇 |
免费 | 14547篇 |
国内免费 | 10151篇 |
专业分类
电工技术 | 10417篇 |
技术理论 | 1篇 |
综合类 | 13007篇 |
化学工业 | 17412篇 |
金属工艺 | 8221篇 |
机械仪表 | 9078篇 |
建筑科学 | 9754篇 |
矿业工程 | 4511篇 |
能源动力 | 3306篇 |
轻工业 | 15270篇 |
水利工程 | 3910篇 |
石油天然气 | 4723篇 |
武器工业 | 1634篇 |
无线电 | 14440篇 |
一般工业技术 | 12464篇 |
冶金工业 | 5144篇 |
原子能技术 | 2037篇 |
自动化技术 | 20012篇 |
出版年
2024年 | 810篇 |
2023年 | 2132篇 |
2022年 | 4717篇 |
2021年 | 6067篇 |
2020年 | 4430篇 |
2019年 | 3365篇 |
2018年 | 3703篇 |
2017年 | 4142篇 |
2016年 | 3776篇 |
2015年 | 5738篇 |
2014年 | 7245篇 |
2013年 | 8644篇 |
2012年 | 10537篇 |
2011年 | 11259篇 |
2010年 | 10462篇 |
2009年 | 10350篇 |
2008年 | 10514篇 |
2007年 | 10111篇 |
2006年 | 8717篇 |
2005年 | 7159篇 |
2004年 | 5120篇 |
2003年 | 3581篇 |
2002年 | 3383篇 |
2001年 | 2982篇 |
2000年 | 2281篇 |
1999年 | 1129篇 |
1998年 | 520篇 |
1997年 | 451篇 |
1996年 | 351篇 |
1995年 | 280篇 |
1994年 | 237篇 |
1993年 | 216篇 |
1992年 | 159篇 |
1991年 | 132篇 |
1990年 | 102篇 |
1989年 | 93篇 |
1988年 | 73篇 |
1987年 | 60篇 |
1986年 | 49篇 |
1985年 | 26篇 |
1984年 | 19篇 |
1983年 | 24篇 |
1982年 | 23篇 |
1981年 | 19篇 |
1980年 | 48篇 |
1979年 | 23篇 |
1977年 | 10篇 |
1976年 | 13篇 |
1959年 | 9篇 |
1951年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
Li‐Qian Ma Jue Wang Eli Shechtman Kalyan Sunkavalli Shi‐Min Hu 《Computer Graphics Forum》2016,35(7):189-197
Shadow removal is a challenging problem and previous approaches often produce de‐shadowed regions that are visually inconsistent with the rest of the image. We propose an automatic shadow region harmonization approach that makes the appearance of a de‐shadowed region (produced using any previous technique) compatible with the rest of the image. We use a shadow‐guided patch‐based image synthesis approach that reconstructs the shadow region using patches sampled from non‐shadowed regions. This result is then refined based on the reconstruction confidence to handle unique textures. Qualitative comparisons over a wide range of images, and a quantitative evaluation on a benchmark dataset show that our technique significantly improves upon the state‐of‐the‐art. 相似文献
922.
Detecting salient objects in challenging images attracts increasing attention as many applications require more robust method to deal with complex images from the Internet. Prior methods produce poor saliency maps in challenging cases mainly due to the complex patterns in the background and internal color edges in the foreground. The former problem may introduce noises into saliency maps and the later forms the difficulty in determining object boundaries. Observing that depth map can supply layering information and more reliable boundary, we improve salient object detection by integrating two features: color information and depth information which are calculated from stereo images. The two features collaborate in a two-stage framework. In the object location stage, depth mainly helps to produce a noise-filtered salient patch, which indicates the location of the object. In the object boundary inference stage, boundary information is encoded in a graph using both depth and color information, and then we employ the random walk to infer more reliable boundaries and obtain the final saliency map. We also build a data set containing 100+ stereo pairs to test the effectiveness of our method. Experiments show that our depth-plus-color based method significantly improves salient object detection compared with previous color-based methods. 相似文献
923.
Dan Song Ruofeng Tong Jian Chang Xiaosong Yang Min Tang Jian Jun Zhang 《Computer Graphics Forum》2016,35(7):147-156
Estimation of 3D body shapes from dressed‐human photos is an important but challenging problem in virtual fitting. We propose a novel automatic framework to efficiently estimate 3D body shapes under clothes. We construct a database of 3D naked and dressed body pairs, based on which we learn how to predict 3D positions of body landmarks (which further constrain a parametric human body model) automatically according to dressed‐human silhouettes. Critical vertices are selected on 3D registered human bodies as landmarks to represent body shapes, so as to avoid the time‐consuming vertices correspondences finding process for parametric body reconstruction. Our method can estimate 3D body shapes from dressed‐human silhouettes within 4 seconds, while the fastest method reported previously need 1 minute. In addition, our estimation error is within the size tolerance for clothing industry. We dress 6042 naked bodies with 3 sets of common clothes by physically based cloth simulation technique. To the best of our knowledge, We are the first to construct such a database containing 3D naked and dressed body pairs and our database may contribute to the areas of human body shapes estimation and cloth simulation. 相似文献
924.
925.
926.
Sanghoon Park Roxana Shabani Mark Schumacher Yoon-Seoung Kim Young Min Bae Kyeong-Hee Lee Hyoung Jin Cho 《Microsystem Technologies》2016,22(8):2077-2085
Miniaturized on-chip blood separators have a great value for point-of-care diagnosis. In our work, a combined design strategy—microfiltration, sedimentation in a retarded flow, and wetting contrast—was taken to overcome the known limitations of on-chip blood separators. Our microfluidic chip consists of a polydimethylsiloxane micropillar array and an etched glass with microchannel branches. The red blood cells are significantly slowed and gradually settled down due to micropillars and enlarged dimension of a chamber. An etched glass microchannel allows the extraction of blood plasma exclusively due to the capillary effect. The fabricated microfluidic device can separate blood plasma from a whole blood sample without any external driving force or dilution. The measured plasma separation efficiency was close to 100 % from human whole blood. Autonomous on-chip separation and collection of blood plasma was demonstrated. 相似文献
927.
针对居民社区公共门窗管理不及时,耗费大量人力资源,且效率较低等问题,设计了一款基于STM32单片机的居民社区门窗禁控制系统.在传统的门禁控制系统的基础上,系统利用Zigbee无线传感网技术,实现门窗禁控制器之间的无线通讯.管理用户可以通过以太网远程控制系统,系统也可以根据传感器监测到的环境数据实现自动调节.同时,尝试采用一种基于频率捷变的分布式自适应干扰技术,解决系统在居民居住环境中遇到的Wifi网络信号干扰问题.最后,通过测试表明,该系统运行稳定,具有广泛的应用前景. 相似文献
928.
随着计算机技术的迅速发展以及人脸识别技术的成熟,人脸美貌度受到越来越多的关注和研究.针对目前的研究方法中存在的对训练数据集的评分过多依赖人工操作,以及对人脸美貌度的预测结果不够详细等问题,本文提出基于HodgeRank的人脸美貌度预测系统,利用数据挖掘方法学习女性人脸的美貌度特征,构造一个模拟预测人脸美貌度的系统.明显区别于之前的研究,该系统训练和测试时采用的人脸数据集放宽了对姿态、光照以及所处环境等条件的限制,评分所需的人工操作大大减少,无需进行大量的人工标定,使用图像的原始像素或纹理特征作为输入,分别采用聚类和改进的BP网络的方法,得到更符合人类特征的美貌度预测结果. 相似文献
929.
Output feedback regulation of upper triangular nonlinear systems with uncertain time‐varying delays in states and input 下载免费PDF全文
In this paper, an output feedback controller is studied to regulate a class of upper triangular nonlinear systems with uncertain time‐varying delays. The key features of our considered system are that there are uncertain time‐varying delays in both states and input and the high‐order nonlinearity is in a more relaxed form over the previous results. Theoretical analysis and numerical example are presented to show the benefits of our controller. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
930.
Jianjun Lei Cuicui Zhang Min Wu Lei You Kefeng Fan Chunping Hou 《Multimedia Tools and Applications》2017,76(6):7661-7676
Large holes are unavoidably generated in depth image based rendering (DIBR) using a single color image and its associated depth map. Such holes are mainly caused by disocclusion, which occurs around the sharp depth discontinuities in the depth map. We propose a divide-and-conquer hole-filling method which refines the background depth pixels around the sharp depth discontinuities to address the disocclusion problem. Firstly, the disocclusion region is detected according to the degree of depth discontinuity, and the target area is marked as a binary mask. Then, the depth pixels located in the target area are modified by a linear interpolation process, whose pixel values decrease from the foreground depth value to the background depth value. Finally, in order to remove the isolated depth pixels, median filtering is adopted to refine the depth map. In these ways, disocclusion regions in the synthesized view are divided into several small holes after DIBR, and are easily filled by image inpainting. Experimental results demonstrate that the proposed method can effectively improve the quality of the synthesized view subjectively and objectively. 相似文献