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81.
Query by image and video content: a colored-based stochastic model approach   总被引:2,自引:0,他引:2  
For efficient image retrieval, the image database should be processed to extract a representing feature vector for each member image in the database. A reliable and robust statistical image indexing technique based on a stochastic model of an image color content has been developed. Based on the developed stochastic model, a compact 12-dimensional feature vector was defined to tag images in the database system. The entries of the defined feature vector are the mean, variance, and skewness of the image color histogram distributions as well as correlation factors between color components of the RGB color space. It was shown using statistical analysis that the feature vector provides sufficient knowledge about the histogram distribution. The reliability and robustness of the proposed technique against common intensity artifacts and noise was validated through several experiments conducted for that purpose. The proposed technique outperforms traditional and other histogram based techniques in terms of feature vector size and properties, as well as performance.  相似文献   
82.
In this paper, a new algorithm for content-based image indexing and retrieval is presented. The proposed method is based on a combination of multiresolution image decomposition and color correlation histogram. According to the new algorithm, wavelet coefficients of the image are computed first using a directional wavelet transform such as Gabor wavelets. A quantization step is then applied before computing one-directional autocorrelograms of the wavelet coefficients. Finally, index vectors are constructed using these one-directional wavelet correlograms. The retrieval results obtained by application of our new method on a 1000 image database demonstrated a significant improvement in effectiveness and efficiency compared to the indexing and retrieval methods based on image color correlogram or wavelet transform.  相似文献   
83.
84.
从文献编目所含有的环节及编目理论的作用入手,着重论述了文献编目中题名的选取、主题词的著录和图书在版编目对书目数据的影响。  相似文献   
85.
This paper addresses an important area in video processing, namely compressed domain processing. For video indexing, video scene transition detection is an essential step to segment the video. Current techniques for scene change detection tend to suffer from a major limitation as most of them cannot identify scene transitions in the compressed domain. Since most video is expected to be stored in the compressed domain, scene transition detection in this domain is highly desirable. In this paper an algorithm for video scene change detection is proposed to overcome this limitation. In this scheme, properties of the B-frames are used as it is capable of measuring the correlation between two adjacent reference frames. The results show that this scheme performs better than schemes based on P-frames. Proposed scheme can be directly applied with compressed data with minimum decompression and hence it is computationally efficient and makes real time implementations possible. Results show that video scene transitions can be identified satisfactorily with the proposed scheme.  相似文献   
86.
Many continual range queries can be issued against data streams. To efficiently evaluate continual queries against a stream, a main memory-based query index with a small storage cost and a fast search time is needed, especially if the stream is rapid. In this paper, we study a CEI-based query index that meets both criteria for efficient processing of continual interval queries. This new query index is an indirect indexing approach. It centres around a set of predefined virtual containment-encoded intervals, or CEIs. The CEIs are used to first decompose query intervals and then perform efficient search operations. The CEIs are defined and labeled such that containment relationships among them are encoded in their IDs. The containment encoding makes decomposition and search operations efficient; from the encoding of the smallest CEI containing a data point, the encodings of other containing CEIs can be easily derived. Closed-form formulae for the bounds of the average index storage cost are derived. Simulations are conducted to evaluate the effectiveness of the CEI-based query index and to compare it with alternative approaches. The results show that the CEI-based query index significantly outperforms existing approaches in terms of both storage cost and search time. Kun-Lung Wu received the B.S. degree in electrical engineering from the National Taiwan University, Taipei, Taiwan, the M.S. and Ph.D. degrees in computer science from the University of Illinois at Urbana–Champaign. He is with the IBM Thomas J. Watson Research Center, currently a member of the Software Tools and Techniques Group. His current research interests include data streams, continual queries, mobile computing, Internet technologies and applications, database systems and distributed and parallel computing. He has published extensively and holds various patents in these areas. Dr. Wu is a Senior Member of the IEEE Computer Society and a member of the ACM. He was an Associate Editor for the IEEE Transactions on Knowledge and Data Engineering, 2000–2004. He was the general chair for the 3rd International Workshop on e-Commerce and Web-Based Information Systems (WECWIS 2001). He has served as an organising and program committee member on various conferences. He has received various IBM awards, including IBM Corporate Environmental Affair Excellence Award, Research Division Award and Invention Achievement Awards. He received a best paper award from IEEE EEE 2004. He is an IBM Master Inventor. Shyh-Kwei Chen received the B.S. degree in computer science and information engineering from National Taiwan University, Taipei, Taiwan, in 1983, the M.S. degree in computer science from the University of Minnesota, Minneapolis, in 1987, and the Ph.D. degree in computer science from University of Illinois at Urbana–Champaign, in 1994. Dr. Chen has been with the IBM Thomas J. Watson Research Center, Yorktown Heights, New York since October 1994, where he is currently a research staff member. His current research interests include XML, electronic commerce, business performance management, data engineering and compilers. He is a member of the ACM, the IEEE and the IEEE Computer Society. Philip S. Yu received the B.S. degree in electrical engineering from National Taiwan University, the M.S. and Ph.D. degrees in electrical engineering from Stanford University, and the M.B.A. degree from New York University. He is with the IBM Thomas J. Watson Research Center and is currently manager of the Software Tools and Techniques group. His research interests include data mining, Internet applications and technologies, database systems, multimedia systems, parallel and distributed processing and performance modelling. Dr. Yu has published more than 400 papers in refereed journals and conferences. He holds or has applied for more than 250 US patents. Dr. Yu is a Fellow of the ACM and a Fellow of the IEEE. He is an associate editor of ACM Transactions on Internet Technology. He is a member of the IEEE Data Engineering steering committee and is also on the steering committee of IEEE Conference on Data Mining. He was the Editor-in-Chief of IEEE Transactions on Knowledge and Data Engineering (2001–2004), an editor and advisory board member of IEEE Transactions on Knowledge and Data Engineering and also a guest coeditor of the special issue on mining of databases. He had also served as an associate editor of Knowledge and Information Systems. In addition to serving as program committee member on various conferences, he was the program cochair of the 11th International Conference on Data Engineering, the 6th Pacific Area Conference on Knowledge Discovery and Data Mining, and the 9th ACM SIGMOD Workshop on Research Issues in Data Mining and Knowledge Discovery, and the program chair of the 2nd International Workshop on Research Issues on Data Engineering: Transaction and Query Processing, the PAKDD Workshop on Knowledge Discovery from Advanced Databases and the 2nd International Workshop on Advanced Issues of E-Commerce and Web-based Information Systems. He served as the general chair of the 14th International Conference on Data Engineering and the general cochair of the 2nd IEEE International Conference on Data Mining. He has received several IBM honours, including two IBM Outstanding Innovation Awards, an Outstanding Technical Achievement Award, two Research Division Awards and the 81st Plateau of Invention Achievement Awards. He received an Outstanding Contributions Award from IEEE International Conference on Data Mining in 2003 and also an IEEE Region 1 Award for “promoting and perpetuating numerous new electrical engineering concepts” in 1999. Dr. Yu is an IBM Master Inventor and was recognised as one of the IBM's 10 top leading inventors in 1999.  相似文献   
87.
弧面分度凸轮机构通用程序的编制与数控加工   总被引:1,自引:0,他引:1  
论述了弧面分度凸轮机构的啮合原理,给出了啮合曲面方程和通用无因次化运动曲线方程,编制了加工弧面分度凸轮的通用程序,并进行了实际加工,所得凸轮经检测与实际使用,其性能达到了设计与使用要求,取得了良好的应用效果。  相似文献   
88.
中文信息导航系统的关键软件技术分析   总被引:4,自引:0,他引:4  
信息导航系统的设计与开发涉及广泛的技术问题。介绍了信息导航系统的特点和现状以及信息导行系统的总体设计,并主要就大规模中文信息导航系统设计中的关键软件技术进行了讨论,包括搜索引擎Robot、中文信息处理系统和导航系统相关服务的设计及其需要解决的主要技术问题,并提供了相应问题的解决方法。最后,简要提到了导航系统设计中需要解决的主要硬件技术问题。  相似文献   
89.
基于相容粗糙集的图形图像信息预检索   总被引:8,自引:0,他引:8  
早期的利用粗糙集理论进行信息检索都是以“等价粗糙集模型”为基础的,但是等价粗糙集的性质限制了该方法的应用范围,为此有些研究者提出以“相容粗糙集模型”代替“等价粗糙集模型”的新的信息检索的概念,此概念的关键在于“关键词的同时发生”和关于相容粗包含的“匹配算法”,提出了一种利用“相容粗糙集”的理论对图形图像进行预检索的新方法,即在相容类的近似空间里对图形图像进行预检索。为了验证这种新方法的有效性,在人脸图形和图像库中做了若干实验,实验结果表明,该方法可以有效地克服等价粗糙集在图形图像检索方面的限制,对提高图形图像的检索效率具有一定的作用。  相似文献   
90.
基于迭代分形的图象压缩和检索方法   总被引:5,自引:0,他引:5  
图象所具有的海量性和无序性的特点,决定了多媒体应用的构建必须解决图象数据的高效压缩和有效检索两个关键问题,而由于传统的压缩和检索技术的研究是相互分离的,因而限制了多媒体应用系统整体性能的提高,针对此问题,从两者相互结合的观点,对图象压缩和检索方法进行了研究,首先在小波变换域内,基于迭代分形对图象数据进行压缩,然后在图象分形码的基础上,利用迭代函数系统分布特性构建的特征量来支持图象检索,实验结果验证了该方法的可行性和有效性,同时也表明了基于迭代分形的图象检索方法所具有的巨大应用潜力。  相似文献   
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