全文获取类型
收费全文 | 8326篇 |
免费 | 53篇 |
国内免费 | 9篇 |
专业分类
电工技术 | 62篇 |
综合类 | 32篇 |
化学工业 | 625篇 |
金属工艺 | 66篇 |
机械仪表 | 69篇 |
建筑科学 | 242篇 |
矿业工程 | 6篇 |
能源动力 | 57篇 |
轻工业 | 5689篇 |
水利工程 | 23篇 |
石油天然气 | 2篇 |
无线电 | 199篇 |
一般工业技术 | 556篇 |
冶金工业 | 417篇 |
原子能技术 | 19篇 |
自动化技术 | 324篇 |
出版年
2012年 | 81篇 |
2011年 | 122篇 |
2010年 | 87篇 |
2009年 | 98篇 |
2008年 | 154篇 |
2007年 | 167篇 |
2006年 | 93篇 |
2005年 | 98篇 |
2004年 | 84篇 |
2002年 | 90篇 |
2001年 | 82篇 |
1998年 | 138篇 |
1997年 | 106篇 |
1996年 | 93篇 |
1995年 | 97篇 |
1990年 | 85篇 |
1989年 | 97篇 |
1988年 | 85篇 |
1987年 | 99篇 |
1986年 | 83篇 |
1985年 | 104篇 |
1984年 | 105篇 |
1980年 | 80篇 |
1978年 | 82篇 |
1977年 | 102篇 |
1976年 | 114篇 |
1974年 | 83篇 |
1973年 | 105篇 |
1972年 | 89篇 |
1971年 | 97篇 |
1970年 | 98篇 |
1969年 | 85篇 |
1968年 | 91篇 |
1967年 | 87篇 |
1966年 | 88篇 |
1956年 | 84篇 |
1917年 | 81篇 |
1916年 | 108篇 |
1915年 | 106篇 |
1914年 | 91篇 |
1913年 | 106篇 |
1912年 | 134篇 |
1911年 | 116篇 |
1910年 | 122篇 |
1909年 | 136篇 |
1908年 | 131篇 |
1907年 | 129篇 |
1906年 | 129篇 |
1905年 | 129篇 |
1904年 | 120篇 |
排序方式: 共有8388条查询结果,搜索用时 0 毫秒
51.
C. Loiseaux S. Graf J. Sifakis A. Bouajjani S. Bensalem David Probst 《Formal Methods in System Design》1995,6(1):11-44
We study property preserving transformations for reactive systems. The main idea is the use of simulations parameterized by Galois connections (, ), relating the lattices of properties of two systems. We propose and study a notion of preservation of properties expressed by formulas of a logic, by a function mapping sets of states of a systemS into sets of states of a systemS'. We give results on the preservation of properties expressed in sublanguages of the branching time -calculus when two systemsS andS' are related via (, )-simulations. They can be used to verify a property for a system by verifying the same property on a simpler system which is an abstraction of it. We show also under which conditions abstraction of concurrent systems can be computed from the abstraction of their components. This allows a compositional application of the proposed verification method.This is a revised version of the papers [2] and [16]; the results are fully developed in [28].This work was partially supported by ESPRIT Basic Research Action REACT.Verimag is a joint laboratory of CNRS, Institut National Polytechnique de Grenoble, Université J. Fourier and Verilog SA associated with IMAG. 相似文献
52.
53.
54.
We study the problems to find a maximum packing of shortest edge-disjoint cycles in a graph of given girth g (g-ESCP) and its vertex-disjoint analogue g-VSCP. In the case g=3, Caprara and Rizzi (2001) have shown that g-ESCP can be solved in polynomial time for graphs with maximum degree 4, but is APX-hard for graphs with maximum degree 5, while g-VSCP can be solved in polynomial time for graphs with maximum degree 3, but is APX-hard for graphs with maximum degree 4. For g∈{4,5}, we show that both problems allow polynomial time algorithms for instances with maximum degree 3, but are APX-hard for instances with maximum degree 4. For each g?6, both problems are APX-hard already for graphs with maximum degree 3. 相似文献
55.
Prof. Dr. Erwin Grochla Direktor Betriebswirtschaftliches Institut für Organisation und Automation an der Universit?t zu
K?ln K?ln Deutschland 《WIRTSCHAFTSINFORMATIK》2009,51(1):104-109
Zusammenfassung Nachdruck eines Aufsatzes aus elektronische datenverarbeitung 11(11)1969:544–548.
This article is also available in English via and : Grochla E (2008) Corporate Information Systems Engineering and Business and Information Systems Engineering as a Necessary
Application-Oriented Extension of General Computer Science – Proposals for Enhancing Academic Education in the Field of Automated
Data Processing in the Federal Republic of Germany. Bus Inf Syst Eng. doi .
相似文献
相似文献
56.
Vasileios Belagiannis Xinchao Wang Horesh Beny Ben Shitrit Kiyoshi Hashimoto Ralf Stauder Yoshimitsu Aoki Michael Kranzfelder Armin Schneider Pascal Fua Slobodan Ilic Hubertus Feussner Nassir Navab 《Machine Vision and Applications》2016,27(7):1035-1046
Multiple human pose estimation is an important yet challenging problem. In an operating room (OR) environment, the 3D body poses of surgeons and medical staff can provide important clues for surgical workflow analysis. For that purpose, we propose an algorithm for localizing and recovering body poses of multiple human in an OR environment under a multi-camera setup. Our model builds on 3D Pictorial Structures and 2D body part localization across all camera views, using convolutional neural networks (ConvNets). To evaluate our algorithm, we introduce a dataset captured in a real OR environment. Our dataset is unique, challenging and publicly available with annotated ground truths. Our proposed algorithm yields to promising pose estimation results on this dataset. 相似文献
57.
58.
Parallel communicating grammar systems with regular control (RPCGS, for short) are introduced, which are obtained from returning regular parallel communicating grammar systems by restricting the derivations that are executed in parallel by the various components through a regular control language. For the class of languages that are generated by RPCGSs with constant communication complexity we derive a characterisation in terms of a restricted type of freely rewriting restarting automaton. From this characterisation we obtain that these languages are semi-linear, and that for RPCGSs with constant communication complexity, the centralised variant has the same generative power as the non-centralised variant. 相似文献
59.
This article presents a method for classifying color points for automotive applications in the Hue Saturation Intensity (HSI)
Space based on the distances between their projections onto the SI plane. Firstly the HSI Space is analyzed in detail. Secondly
the projection of image points from a typical automotive scene onto the SI plane is shown. The minimal classes relevant for
driver assistance applications are derived. The requirements for the classification of the points into those classes are obtained.
Several weighting functions are proposed and a fast form of an euclidean metric is investigated in detail. In order to improve
the sensitivity of the weighting function, dynamic coefficients are introduced. It is shown how to compute them automatically
in order to get optimal results for the classification. Finally some results of applying the metric to the sample images are
shown and the conclusions are drawn.
Calin Rotaru is a PhD candidate at the Department of Computer Science, University of Hamburg, Germany. His PhD work focuses on the topic color machine vision for driver assistance systems and is supported by Volkswagen AG, Group Research Electronics. He graduated (2002) with the topic “Stereo Camera Based Object Recognition” for Driver Assistance Systems from the Faculty of Automation and Computer Science of the Technical University of Cluj-Napoca, Romania. His research interests include color machine vision, smart vision systems, multisensorial data fusion and vision in driver assistance systems. Thorsten Graf received the diploma (M.Sc.) degree in computer science and the Ph.D. degree (his thesis was on “Flexible Object Recognition Based on Invariant Theory and Agent Technology”) from the University of Bielefeld, Bielefeld, Germany, in 1997 and 2000, respectively. In 1997 he became a Member of the “Task Oriented Communication” graduate program, University of Bielefeld, funded by the German research foundation DFG. In June 2001 he joined Volkswagen Group Research, Wolfsburg, Germany. Since then, he has worked on different projects in the area of driver assistance systems as a Researcher and Project Leader. He is the author or coauthor of more than 40 publications and owns several patents. His research interests include image processing and analysis dedicated to advanced comfort/safety automotive applications. Dr. Jianwei Zhang is full professor and director of the Institute of Technical Aspects of Multimodal Systems, Department of Computer Science, University of Hamburg, Germany. He is one of the Chair Professors “Human-Computer Interaction” of the Department of Computer Science of Tsinghua University. He received his Bachelor (1986) and Master degree (1989) from the Department of Computer Science of Tsinghua University, and his PhD (1994) from the Department of Computer Science, University of Karlsruhe, Germany. His research interests include multimodal information processing, robot learning, service robots, smart vision systems and Embodied Intelligence. In these areas he has published over 120 journal and conference papers, six book chapters and two research monographs. He leads numerous basic research and application projects, including the EU basic research programs and the Collaborative Research Centre supported by the German Research Council. Dr. Zhang has received multiple awards including the IEEE ROMAN Best Paper 2002. 相似文献
Jianwei ZhangEmail: |
Calin Rotaru is a PhD candidate at the Department of Computer Science, University of Hamburg, Germany. His PhD work focuses on the topic color machine vision for driver assistance systems and is supported by Volkswagen AG, Group Research Electronics. He graduated (2002) with the topic “Stereo Camera Based Object Recognition” for Driver Assistance Systems from the Faculty of Automation and Computer Science of the Technical University of Cluj-Napoca, Romania. His research interests include color machine vision, smart vision systems, multisensorial data fusion and vision in driver assistance systems. Thorsten Graf received the diploma (M.Sc.) degree in computer science and the Ph.D. degree (his thesis was on “Flexible Object Recognition Based on Invariant Theory and Agent Technology”) from the University of Bielefeld, Bielefeld, Germany, in 1997 and 2000, respectively. In 1997 he became a Member of the “Task Oriented Communication” graduate program, University of Bielefeld, funded by the German research foundation DFG. In June 2001 he joined Volkswagen Group Research, Wolfsburg, Germany. Since then, he has worked on different projects in the area of driver assistance systems as a Researcher and Project Leader. He is the author or coauthor of more than 40 publications and owns several patents. His research interests include image processing and analysis dedicated to advanced comfort/safety automotive applications. Dr. Jianwei Zhang is full professor and director of the Institute of Technical Aspects of Multimodal Systems, Department of Computer Science, University of Hamburg, Germany. He is one of the Chair Professors “Human-Computer Interaction” of the Department of Computer Science of Tsinghua University. He received his Bachelor (1986) and Master degree (1989) from the Department of Computer Science of Tsinghua University, and his PhD (1994) from the Department of Computer Science, University of Karlsruhe, Germany. His research interests include multimodal information processing, robot learning, service robots, smart vision systems and Embodied Intelligence. In these areas he has published over 120 journal and conference papers, six book chapters and two research monographs. He leads numerous basic research and application projects, including the EU basic research programs and the Collaborative Research Centre supported by the German Research Council. Dr. Zhang has received multiple awards including the IEEE ROMAN Best Paper 2002. 相似文献
60.
Larsen L Griffin LD Grässel D Witte OW Axer H 《Microscopy research and technique》2007,70(10):851-863
Polarized light imaging (PLI) is a method to image fiber orientation in gross histological brain sections based on the birefringent properties of the myelin sheaths. The method uses the transmission of polarized light to quantitatively estimate the fiber orientation and inclination angles at every point of the imaged section. Multiple sections can be assembled into a 3D volume, from which the 3D extent of fiber tracts can be extracted. This article describes the physical principles of PLI and describes two major applications of the method: the imaging of white matter orientation of the rat brain and the generation of fiber orientation maps of the human brain in white and gray matter. The strengths and weaknesses of the method are set out. 相似文献