全文获取类型
收费全文 | 8208篇 |
免费 | 541篇 |
国内免费 | 10篇 |
专业分类
电工技术 | 110篇 |
综合类 | 9篇 |
化学工业 | 2321篇 |
金属工艺 | 100篇 |
机械仪表 | 184篇 |
建筑科学 | 278篇 |
矿业工程 | 11篇 |
能源动力 | 376篇 |
轻工业 | 1452篇 |
水利工程 | 43篇 |
石油天然气 | 45篇 |
无线电 | 564篇 |
一般工业技术 | 1232篇 |
冶金工业 | 378篇 |
原子能技术 | 65篇 |
自动化技术 | 1591篇 |
出版年
2024年 | 9篇 |
2023年 | 79篇 |
2022年 | 330篇 |
2021年 | 347篇 |
2020年 | 225篇 |
2019年 | 238篇 |
2018年 | 283篇 |
2017年 | 306篇 |
2016年 | 353篇 |
2015年 | 240篇 |
2014年 | 409篇 |
2013年 | 654篇 |
2012年 | 533篇 |
2011年 | 660篇 |
2010年 | 500篇 |
2009年 | 518篇 |
2008年 | 471篇 |
2007年 | 388篇 |
2006年 | 319篇 |
2005年 | 239篇 |
2004年 | 211篇 |
2003年 | 184篇 |
2002年 | 196篇 |
2001年 | 106篇 |
2000年 | 85篇 |
1999年 | 95篇 |
1998年 | 149篇 |
1997年 | 105篇 |
1996年 | 74篇 |
1995年 | 64篇 |
1994年 | 42篇 |
1993年 | 38篇 |
1992年 | 31篇 |
1991年 | 16篇 |
1990年 | 20篇 |
1989年 | 25篇 |
1988年 | 24篇 |
1987年 | 12篇 |
1986年 | 21篇 |
1985年 | 22篇 |
1984年 | 19篇 |
1983年 | 9篇 |
1982年 | 20篇 |
1981年 | 12篇 |
1980年 | 12篇 |
1979年 | 13篇 |
1978年 | 11篇 |
1977年 | 12篇 |
1976年 | 10篇 |
1975年 | 6篇 |
排序方式: 共有8759条查询结果,搜索用时 15 毫秒
101.
This work presents a general mechanism for executing specifications that comply with given invariants, which may be expressed in different formalisms and logics. We exploit Maude’s reflective capabilities and its properties as a general semantic framework to provide a generic strategy that allows us to execute Maude specifications taking into account user-defined invariants. The strategy is parameterized by the invariants and by the logic in which such invariants are expressed. We experiment with different logics, providing examples for propositional logic, (finite future time) linear temporal logic and metric temporal logic. 相似文献
102.
Antonio C. Sobieranski Daniel D. Abdala Eros Comunello Aldo von Wangenheim 《Pattern recognition letters》2009,30(16):127
In this paper we describe an experiment where we studied empirically the application of a learned distance metric to be used as discrimination function for an established color image segmentation algorithm. For this purpose we chose the Mumford–Shah energy functional and the Mahalanobis distance metric. The objective was to test our approach in an objective and quantifiable way on this specific algorithm employing this particular distance model, without making generalization claims. The empirical validation of the results was performed in two experiments: one applying the resulting segmentation method on a subset of the Berkeley Image Database, an exemplar image set possessing ground-truths and validating the results against the ground-truths using two well-known inter-cluster validation methods, namely, the Rand and BGM indexes, and another experiment using images of the same context divided into training and testing set, where the distance metric is learned from the training set and then applied to segment all the images. The obtained results suggest that the use of the specified learned distance metric provides better and more robust segmentations, even if no other modification of the segmentation algorithm is performed. 相似文献
103.
TextonBoost for Image Understanding: Multi-Class Object Recognition and Segmentation by Jointly Modeling Texture,Layout, and Context 总被引:5,自引:0,他引:5
Jamie Shotton John Winn Carsten Rother Antonio Criminisi 《International Journal of Computer Vision》2009,81(1):2-23
This paper details a new approach for learning a discriminative model of object classes, incorporating texture, layout, and
context information efficiently. The learned model is used for automatic visual understanding and semantic segmentation of
photographs. Our discriminative model exploits texture-layout filters, novel features based on textons, which jointly model patterns of texture and their spatial layout. Unary classification
and feature selection is achieved using shared boosting to give an efficient classifier which can be applied to a large number
of classes. Accurate image segmentation is achieved by incorporating the unary classifier in a conditional random field, which
(i) captures the spatial interactions between class labels of neighboring pixels, and (ii) improves the segmentation of specific
object instances. Efficient training of the model on large datasets is achieved by exploiting both random feature selection
and piecewise training methods.
High classification and segmentation accuracy is demonstrated on four varied databases: (i) the MSRC 21-class database containing
photographs of real objects viewed under general lighting conditions, poses and viewpoints, (ii) the 7-class Corel subset
and (iii) the 7-class Sowerby database used in He et al. (Proceeding of IEEE Conference on Computer Vision and Pattern Recognition,
vol. 2, pp. 695–702, June 2004), and (iv) a set of video sequences of television shows. The proposed algorithm gives competitive and visually pleasing results
for objects that are highly textured (grass, trees, etc.), highly structured (cars, faces, bicycles, airplanes, etc.), and
even articulated (body, cow, etc.).
J. Shotton is now working at Toshiba Corporate Research & Development Center, Kawasaki, Japan. 相似文献
104.
Luis Moreno Santiago Garrido Dolores Blanco M. Luisa Muñoz 《Robotics and Autonomous Systems》2009,57(4):441-450
A new solution to the Simultaneous Localization and Modelling problem is presented in this paper. The algorithm is based on the stochastic search for solutions in the state space to the global localization problem by means of a differential evolution algorithm. This non linear evolutive filter, called Evolutive Localization Filter (ELF), searches stochastically along the state space for the best robot pose estimate. The set of pose solutions (the population) focuses on the most likely areas according to the perception and up to date motion information. The population evolves using the log-likelihood of each candidate pose according to the observation and the motion errors derived from the comparison between observed and predicted data obtained from the probabilistic perception and motion model.The proposed SLAM algorithm operates in two steps: in the first step the ELF filter is used at local level to re-localize the robot based on the robot odometry, the laser scan at a given position and a local map where only a low number of the last scans have been integrated. In the second step, the aligned laser measures and the corrected robot poses are used to detect whether the robot is revisiting a previously crossed area (i.e., a cycle in the robot trajectory exists). Once a cycle is detected, the Evolutive Localization Filter is used again to estimate the accumulated residual drift in the detected loop and then to re-estimate the robot poses in order to integrate the sensor measures in the global map of the environment.The algorithm has been tested in different environments to demonstrate the effectiveness, robustness and computational efficiency of the proposed approach. 相似文献
105.
106.
107.
108.
Cabitza Federico Fogli Daniela Lanzilotti Rosa Piccinno Antonio 《Multimedia Tools and Applications》2017,76(4):5221-5241
Multimedia Tools and Applications - This paper describes a 63-participant user study that compares two widely known systems supporting end users in creating trigger-action rules for the Internet of... 相似文献
109.
110.