全文获取类型
收费全文 | 659篇 |
免费 | 20篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 25篇 |
化学工业 | 143篇 |
金属工艺 | 14篇 |
机械仪表 | 15篇 |
建筑科学 | 16篇 |
能源动力 | 60篇 |
轻工业 | 36篇 |
水利工程 | 1篇 |
石油天然气 | 9篇 |
无线电 | 67篇 |
一般工业技术 | 72篇 |
冶金工业 | 44篇 |
自动化技术 | 185篇 |
出版年
2023年 | 4篇 |
2022年 | 13篇 |
2021年 | 25篇 |
2020年 | 15篇 |
2019年 | 21篇 |
2018年 | 31篇 |
2017年 | 25篇 |
2016年 | 36篇 |
2015年 | 20篇 |
2014年 | 28篇 |
2013年 | 57篇 |
2012年 | 27篇 |
2011年 | 46篇 |
2010年 | 22篇 |
2009年 | 33篇 |
2008年 | 24篇 |
2007年 | 18篇 |
2006年 | 21篇 |
2005年 | 11篇 |
2004年 | 14篇 |
2003年 | 16篇 |
2002年 | 6篇 |
2000年 | 9篇 |
1999年 | 5篇 |
1998年 | 27篇 |
1997年 | 11篇 |
1996年 | 4篇 |
1995年 | 11篇 |
1994年 | 12篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 10篇 |
1987年 | 8篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1974年 | 3篇 |
1973年 | 8篇 |
1972年 | 5篇 |
1971年 | 4篇 |
1969年 | 2篇 |
排序方式: 共有687条查询结果,搜索用时 46 毫秒
31.
Brahim Wael Betrouni Nacim Mestiri Makram Hamrouni Kamel 《Multimedia Tools and Applications》2019,78(10):13033-13046
Multimedia Tools and Applications - The involvement of medical imaging in medical procedures plays an important role in the diagnosis and planning of a therapeutic treatment. Computerized... 相似文献
32.
Rik Bhnemann Michael Pantic Marija Popovi Dominik Schindler Marco Tranzatto Mina Kamel Marius Grimm Jakob Widauer Roland Siegwart Juan Nieto 《野外机器人技术杂志》2019,36(1):78-103
This study describes the hardware and software systems of the Micro Aerial Vehicle (MAV) platforms used by the ETH Zurich team in the 2017 Mohamed Bin Zayed International Robotics Challenge (MBZIRC). The aim was to develop robust outdoor platforms with the autonomous capabilities required for the competition, by applying and integrating knowledge from various fields, including computer vision, sensor fusion, optimal control, and probabilistic robotics. This paper presents the major components and structures of the system architectures and reports on experimental findings for the MAV‐based challenges in the competition. Main highlights include securing the second place both in the individual search, pick, and place the task of Challenge 3 and the Grand Challenge, with autonomous landing executed in less than 1 min and a visual servoing success rate of over for object pickups. 相似文献
33.
Clear poly(methyl-methacrylate)—PMMA—dosimeter is widely used in food irradiations. Positron annihilation lifetime spectroscopy (PALS) is one of the unique tools used for studying free-volumes and open-volume type defects in solid media. The Vicker's microhardness measurements offer a simple and nondestructive tool for investigating the mechanical behavior of polymer materials. PALS as well as microhardness measurements were carried out for PMMA samples, irradiated with low- and high-linear energy transfers (LET). The low-LET irradiations were provided at lethal doses of gamma radiations for vegetative bacteria. Such irradiations showed a chain scission in the PMMA samples. High-LET irradiations showed behavior different from the low-LET ones. The observed behavior depends on the alpha particle fluence. The microhardness testing was carried out for virgin and irradiated PMMA samples at high-LET. A negative correlation was found between PALS measurements and microhardness results. The optical characteristics and structural studies for the virgin and irradiated PMMA samples were in agreement with the PALS and microhardness measurements. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
34.
The COVID-19 pandemic has affected the educational systems worldwide, leading to the near-total closures of schools, universities, and colleges. Universities need to adapt to changes to face this crisis without negatively affecting students’ performance. Accordingly, the purpose of this study is to identify and help solve to critical challenges and factors that influence the e-learning system for Computer Maintenance courses during the COVID-19 pandemic. The paper examines the effect of a hybrid modeling approach that uses Cloud Computing Services (CCS) and Virtual Reality (VR) in a Virtual Cloud Learning Environment (VCLE) system. The VCLE system provides students with various utilities and educational services such as presentation slides/text, data sharing, assignments, quizzes/tests, and chatrooms. In addition, learning through VR enables the students to simulate physical presence, and they respond well to VR environments that are closer to reality as they feel that they are an integral part of the environment. Also, the research presents a rubric assessment that the students can use to reflect on the skills they used during the course. The research findings offer useful suggestions for enabling students to become acquainted with the proposed system’s usage, especially during the COVID-19 pandemic, and for improving student achievement more than the traditional methods of learning. 相似文献
35.
Imen Gueddi Othman Nasri Kamel Ben Othman 《International Journal of Adaptive Control and Signal Processing》2020,34(1):42-62
This paper presents a new optimized interval principal component analysis applied to detect and isolate actuators faults of an autonomous spacecraft involved in the rendezvous phase of the Mars sample return mission. Based on the exploitation of various arithmetic and interval analysis properties, the new interval model is built by solving the interval eigenpairs problem via a resolution of a parametric linear programming problem. The detection and isolation phases are performed by extending the classic methods to interval-valued data. The proposed method is applied to detect and isolate actuators faults that can occur on the spacecraft's thrusters. Based on data provided by a “high fidelity” industrial simulator developed by Thales Alenia Space, the obtained results proved the effectiveness of the proposed interval fault diagnosis method on detecting and isolating thrusters' faults. 相似文献
36.
37.
Said Nemmich Mohamed Elmouloud Zelmat Kamel Nassour Nacera Hammadi Abdelkader Draou 《The International journal of environmental studies》2019,76(4):571-581
Although the dielectric barrier discharge (DBD) has been widely considered and studied for ozone generation, only a few studies have examined the influence of the alternating voltage waveform on the ozone rate production. This paper analyses the influence of the voltage shape on the ozone concentration and the energy efficiency of a DBD cylindrical ozone generator. Three voltage signals were studied using a high-voltage amplifier: sinusoidal, triangular and rectangular signals with voltage values up to 8 kV and frequencies up to 1.1 kHz. The obtained results showed that the efficiency of the ozone generator depends strongly on the type of the voltage waveform. The maximum values of the energy efficiency and the ozone concentration were obtained with the triangular voltage signal. This wave shape configuration has been successfully used for discolouration of water contaminated by textile dye. 相似文献
38.
39.
40.
Kamel Tourki Mohamed‐Slim Alouini Khalid A. Qaraqe Hong‐Chuan Yang 《Wireless Communications and Mobile Computing》2015,15(2):367-378
Opportunistic relaying in cooperative communication depends on careful relay selection. However, the traditional centralized method used for opportunistic amplify‐and‐forward protocols requires precise measurements of channel state information at the destination. In this paper, we adopt the max–min criterion as a relay selection framework for opportunistic amplify‐and‐forward cooperative communications, which was exhaustively used for the decode‐and‐forward protocol, and offer an accurate performance analysis based on exact statistics of the local signal‐to‐noise ratios of the best relay. Furthermore, we evaluate the asymptotical performance and deduce the diversity order of our proposed scheme. Finally, we validate our analysis by showing that performance simulation results coincide with our analytical results over Rayleigh fading channels, and we compare the max–min relay selection with their centralized channel state information‐based and partial relay selection counterparts. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献