全文获取类型
收费全文 | 2131篇 |
免费 | 42篇 |
国内免费 | 12篇 |
专业分类
电工技术 | 124篇 |
综合类 | 3篇 |
化学工业 | 486篇 |
金属工艺 | 150篇 |
机械仪表 | 29篇 |
建筑科学 | 34篇 |
能源动力 | 92篇 |
轻工业 | 130篇 |
水利工程 | 4篇 |
无线电 | 219篇 |
一般工业技术 | 363篇 |
冶金工业 | 362篇 |
原子能技术 | 47篇 |
自动化技术 | 142篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 30篇 |
2020年 | 11篇 |
2019年 | 25篇 |
2018年 | 29篇 |
2017年 | 25篇 |
2016年 | 34篇 |
2015年 | 20篇 |
2014年 | 40篇 |
2013年 | 111篇 |
2012年 | 78篇 |
2011年 | 106篇 |
2010年 | 66篇 |
2009年 | 110篇 |
2008年 | 77篇 |
2007年 | 76篇 |
2006年 | 68篇 |
2005年 | 62篇 |
2004年 | 52篇 |
2003年 | 62篇 |
2002年 | 73篇 |
2001年 | 63篇 |
2000年 | 46篇 |
1999年 | 58篇 |
1998年 | 153篇 |
1997年 | 66篇 |
1996年 | 74篇 |
1995年 | 58篇 |
1994年 | 76篇 |
1993年 | 44篇 |
1992年 | 36篇 |
1991年 | 43篇 |
1990年 | 36篇 |
1989年 | 25篇 |
1988年 | 19篇 |
1987年 | 19篇 |
1986年 | 26篇 |
1985年 | 22篇 |
1984年 | 26篇 |
1983年 | 19篇 |
1982年 | 12篇 |
1981年 | 13篇 |
1980年 | 11篇 |
1979年 | 14篇 |
1978年 | 9篇 |
1977年 | 12篇 |
1976年 | 13篇 |
1975年 | 6篇 |
1973年 | 6篇 |
排序方式: 共有2185条查询结果,搜索用时 15 毫秒
71.
Makio Kurashige Kazutoshi Ishida Tomoe Takanokura Yasuyuki Ohyagi Masachika Watanabe 《Journal of the Society for Information Display》2011,19(9):631-638
Abstract— While laser projection has many advantages, there is a problem with speckle patterns generated as a result of interference of the laser beam and results in bad effects to observers. In 2010, a variable speckle generator, which produces an angular shift of incident light to the screen and generates variable speckle patterns, was suggested. In this study, the performance of a variable speckle generator by using a volume phase holographic beam shaper and scanning mirror was investigated in detail by evaluating both the objective and subjective speckle contrast. The morphology of the speckle pattern was also investigated when the variable speckle generator was activated. With a scanning VPH beam shaper, the objective speckle was effectively reduced because each point of the VPH beam shaper generated different speckle patterns and coherency among each pattern disappeared by using the scan process. On the other hand, subjective speckle was also dramatically reduced by changing the incident angle on the screen, which resulted in generating variable subjective speckle. It was also shown that the speckle reduction rate by using a variable speckle generator did not depend on the coherent length of a laser by evaluating the normalized speckle contrast against the angular shift on the screen. 相似文献
72.
Implementation of a decision support system using an interactive large-scale high-resolution display
Tomoyuki Ishida Yusuke Hirohara Nobuyuki Kukimoto Yoshitaka Shibata 《Artificial Life and Robotics》2017,22(3):385-390
In this research, we propose and evaluate a decision support system using an interactive large-scale high-resolution display. This decision support system supports the summarization and decision-making of a large amount of disaster information during the occurrence of a large-scale natural disaster. Municipal employees at the disaster control headquarters can display disaster information on the large-scale display with a touch or flick on a laptop or tablet. To evaluate the operability, readability, functionality, and necessity of the decision support system, we surveyed 23 municipal employees in the disaster prevention division using a questionnaire. The system received a great evaluation in all the evaluation items. 相似文献
73.
We propose a recognition method of character-string images captured by portable digital cameras. A challenging task in character-string
recognition is the segmentation of characters. In the proposed method, a hypothesis graph is used for recognition-based segmentation
of the character-string images. The hypothesis graph is constructed by the subspace method, using eigenvectors as conditionally
elastic templates. To obtain these templates, a generation-based approach is introduced in the training stage. Various templates
are generated to cope with low-resolution. We have experimentally proved that the proposed scheme achieves high recognition
performance even for low-resolution character-string images.
The text was submitted by the authors in English.
Hiroyuki Ishida. Received his B.S. and M.S. degrees from the Department of Information Engineering and from the Graduate School of Information
Science, respectively, at Nagoya University. He is currently pursuing a Ph.D. in Information Science at Nagoya University.
Ichiro Ide. Received his B.S. degree from the Department of Electronic Engineering, his M.S. degree from the Department of Information
Engineering, and his Ph.D. from the Department of Electrical Engineering at the University of Tokyo. He is currently an Associate
Professor in the Graduate School of Information Science at Nagoya University.
Tomokazu Takahashi. Received his B.S. degree from the Department of Information Engineering at Ibaraki University, and his M.S. and Ph.D. from
the Graduate School of Science and Engineering at Ibaraki University. His research interests include computer graphics and
image recognition.
Hiroshi Murase. Received his B.S., M.S., and Ph.D. degrees from the Graduate School of Electrical Engineering at Nagoya University. He is
currently a Professor in the Graduate School of Information Science at Nagoya University. He received the Ministry Award from
the Ministry of Education, Culture, Sports, Science and Technology in Japan in 2003. He is a Fellow of the IEEE. 相似文献
74.
Yoshiteru Ishida 《Artificial Life and Robotics》2008,12(1-2):125-128
Antibodies, among other things, are important components of the immune system. This paper proposes using the specific recognition
capability exhibited by antibodies for computation, in particular, for solving the stable marriage problem, which has been studied as a combinatorial computational problem. Antibody-based computation is proposed by integrating the
recognition capabilities of antibodies. The computation is carried out on an array form that is suitable not only for expressing
stable marriage problems, but also for further integration to antibody microarrays.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
75.
Yoshimitsu Aoki Shuji Hashimoto Masahiko Terajima Akihiko Nakasima 《The Visual computer》2001,17(2):121-131
We propose a prototype of a facial surgery simulation system for surgical planning and the prediction of facial deformation.
We use a physics-based human head model. Our head model has a 3D hierarchical structure that consists of soft tissue and the
skull, constructed from the exact 3D CT patient data. Anatomic points measured on X-ray images from both frontal and side
views are used to fire the model to the patient's head.
The purposes of this research is to analyze the relationship between changes of mandibular position and facial morphology
after orthognathic surgery, and to simulate the exact postoperative 3D facial shape. In the experiment, we used our model
to predict the facial shape after surgery for patients with mandibular prognathism. Comparing the simulation results and the
actual facial images after the surgery shows that the proposed method is practical. 相似文献
76.
Akihiko Nagata Osamu Izumi Kōshichi Noto Hiroshi Hirayama 《Journal of Materials Science》1978,13(4):731-738
The dilute Cu-Nb-Sn alloys containing small amounts of Nb and Sn less than 1 at % exhibited superconductivity after quenching from the liquid state and ageing. The best superconducting properties (
andJ
c=130 A cm–2) in a Cu-0.30 at % Nb 0.15 at % Sn alloy were obtained when the sample was aged at 550° C for 384 h. This sample exhibited a structure of fine Nb3Sn precipitates of 200 to 500Å diameter distributed homogeneously in the Cu matrix, and therefore it was concluded that superconductivity in these alloys resulted from the proximity effect of Nb3Sn particles. In spite of the similar structure obtained by ageing at 800° C, the Cu-Nb-Sn alloys showed inferior superconducting properties compared to the Cu-0.4 at % Nb alloy and this would be explained qualitatively by the difference in the mean free path in the two alloys. 相似文献
77.
78.
Koji Ishida Ken Hirota Osamu Yamaguchi Hideki Kume Suguru Inamura Hiroki Miyamoto 《Journal of the American Ceramic Society》1994,77(5):1391-1395
In the system ZrO2 –Al2 O3 , a new method for preparing ZrO2 solid solutions from ZrCl4 and AlCl3 using hydrazine monohydrate is investigated. c -ZrO2 solid solutions containing up to ∼40 mol% Al2 O3 crystallize at low temperatures from amorphous materials. The formation mechanism is discussed from IR spectral data. The values of the lattice parameter α increase linearly from 0.5072 to 0.5105 nm with increasing Al2 O3 content. At higher temperatures, transformation of the solid solutions proceeds as follows: c ( SS ) → t ( ss ) → t ( ss ) +α-Al2 O3 → m +α-Al2 O3 . m -ZrO2 –α-Al2 O3 composite ceramics are fabricated by hot isostatic pressing for 2 h at 1250°C and 196 MPa. Microstructures and mechanical properties are examined, in connection with increasing Al2 O3 content. 相似文献
79.
Toshio Ogasawara Yuichi Ishida Takashi Ishikawa Takahira Aoki Toshiyuki Ogura 《Composites Part A》2006,37(12):2236-2240
Helium gas permeability of silicate clay (montmorillonite) particles/epoxy nanocomposites was examined. The incorporation of increasing amounts of montmorillonite particles reduced the helium gas permeability. Based on Fick’s law, gas permeation behavior of the nanocomposite was evaluated. With the increase of montmorillonite loading, gas diffusivity decreased, while gas solubility increased. Helium diffusion behavior is in agreement to the numerical results based on the Hatta–Taya–Eshelby theory. It has been revealed that dispersion of nanoscale platelets in polymer is effective in improving gas barrier property. 相似文献
80.
Tunable Optical Notch Filter Realized by Shifting the Photonic Bandgap in a Silicon Photonic Crystal Line-Defect Waveguide 总被引:1,自引:0,他引:1
Chu T. Yamada H. Gomyo A. Ushida J. Ishida S. Arakawa Y. 《Photonics Technology Letters, IEEE》2006,18(24):2614-2616
A tunable optical notch filter was realized by thermally shifting the TM-like (the light's electric field perpendicular to the substrate) bandgap of a silicon photonic crystal slab W1 line-defect waveguide with silica cladding. This device is compact-its footprint is 340times16 mum2, excluding the electrode pads. The 3-dB bandwidth of the device was about 5 nm, and the extinction ratio at the center wavelength was as high as 40 dB. A maximum center wavelength shift of 17.9 nm was attained at a heating power of 0.7W, with a tuning efficiency of 25.5 nm/W. The tuning response time was less than 100 mus 相似文献