全文获取类型
收费全文 | 1459篇 |
免费 | 16篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 81篇 |
综合类 | 2篇 |
化学工业 | 260篇 |
金属工艺 | 119篇 |
机械仪表 | 15篇 |
建筑科学 | 17篇 |
能源动力 | 53篇 |
轻工业 | 55篇 |
水利工程 | 4篇 |
无线电 | 190篇 |
一般工业技术 | 214篇 |
冶金工业 | 346篇 |
原子能技术 | 35篇 |
自动化技术 | 88篇 |
出版年
2022年 | 8篇 |
2021年 | 16篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 12篇 |
2017年 | 10篇 |
2016年 | 20篇 |
2015年 | 9篇 |
2014年 | 22篇 |
2013年 | 64篇 |
2012年 | 35篇 |
2011年 | 61篇 |
2010年 | 36篇 |
2009年 | 65篇 |
2008年 | 42篇 |
2007年 | 37篇 |
2006年 | 46篇 |
2005年 | 39篇 |
2004年 | 28篇 |
2003年 | 35篇 |
2002年 | 50篇 |
2001年 | 51篇 |
2000年 | 36篇 |
1999年 | 46篇 |
1998年 | 142篇 |
1997年 | 56篇 |
1996年 | 68篇 |
1995年 | 47篇 |
1994年 | 60篇 |
1993年 | 36篇 |
1992年 | 34篇 |
1991年 | 34篇 |
1990年 | 31篇 |
1989年 | 19篇 |
1988年 | 15篇 |
1987年 | 15篇 |
1986年 | 23篇 |
1985年 | 15篇 |
1984年 | 17篇 |
1983年 | 18篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 7篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1977年 | 2篇 |
1976年 | 12篇 |
1975年 | 3篇 |
1972年 | 4篇 |
1969年 | 1篇 |
排序方式: 共有1479条查询结果,搜索用时 0 毫秒
31.
Various composites of polyethylene, ethylene propylene diene rubber (EPDM), and filler are milled and analysed by solid-state dynamic mechanical spectroscopy. The filler used is silicon powder with an oxidized surface. This filler is a model for materials with siliceous surfaces. The torsion pendulum measurements show that the multicomponent composites exhibited complex viscoelastic behaviour. For composites of polyethylene and silicon dioxide, there is evidence of particle-particle interactions. In composites which include polyethylene, rubber and filler, interactions of the polyethylene and especially of the rubber with the filler surface are significant. Treatment of the filler surface with gamma-aminopropyltriethoxysilane (-APS) or gamma-methacryloxypropyltrimethoxysilane (-MPS) has a significant influence on the resultant composite dynamic mechanical spectrum. Maleic anhydride grafting of the EPDM rubber also changes the character of the composites. These composites appear to exhibit complex morphologies, which may be controlled to a certain extent by filler surface treatment and grafting to the rubber. There is evidence for a chemical reaction between the maleic anhydride modification of the EPDM and -APS during processing on the roll mill. Prediction of the composite properties using the extended van der Poel model is qualitatively useful. 相似文献
32.
Z. Moser W. Gąsior K. Bukat J. Pstruś R. Kisiel J. Sitek K. Ishida I. Ohnuma 《Journal of Phase Equilibria and Diffusion》2006,27(2):133-139
Maximum bubble pressure, dilatometric, and meniscographic methods were used in the investigations of the surface tension,
density, wetting time, wetting force, contact angle, and interfacial tension of liquid alloys of Sn−Ag−Cu eutectic composition
with various additions of Bi. Density and surface tension measurements were conducted in the temperature range 250–900 °C.
Surface tensions at 250 °C measured under a protective atmosphere of Ar−H2 were combined with data from meniscographic studies done under air or with a protective flux. The meniscographic data with
a nonwetted teflon substrate provided data on interfacial tension (solder-flux), surface tension in air, and meniscographic
data with a Cu substrate allowed determinations of wetting time, wetting force, and calculation of contact angle. The calculated
wetting angles from meniscographic studies for binary Sn−Ag eutectic and two ternary Sn−Ag−Cu alloys were verified by separate
measurements by the sessile drop method under a protective atmosphere with a Cu substrate. Additions of Bi to both ternary
alloys improve the wettability and move the parameters somewhat closer to those of traditional Sn−Pb solders. 相似文献
33.
I. Ohnuma K. Ishida Z. Moser S. Gąsior K. Bukat J. Pstruś R. Kisiel J. Sitek 《Journal of Phase Equilibria and Diffusion》2006,27(3):245-254
The ADAMIS database was used for calculation of the surface tension of the quaternary Sn−Ag−Cu−Bi liquid alloys by Butler's
model. The resultant data were compared with those from the maximum bubble pressure measurements from Part I. The same thermodynamic
database was next applied for the calculation of various phase equilibria. It was established that the Bi addition to the
ternary Sn−Ag−Cu alloys (Sn-2.6Ag-0.46Cu and Sn-3.13Ag-0.74Cu in at.%; Sn-2.56Ag-0.26 Cu and Sn-2.86Ag-O.40Cu in mass%) causes
lowering of the melting temperature and the surface tension to make the tested alloys closer to, traditional Sn−Pb solders.
The simulation of the solidification by Scheil's model showed that the alloys with the higher Bi concentration are characterized
by the lifting-off failure due to the segregation of Bi at the solder/substrate boundary. Thus, in modeling of new Pb-free
solders, a compromise among various properties should be taken into consideration. 相似文献
34.
The optical behavior of a thin film, that is, peak positions and intensities, is discussed for transmission under a thin-film approximation. The infrared transmission spectra of thin films, both standing films and those on dielectric substrates, are simulated for s and p polarization at various angles of incidence. For spectral simulation, the matrix method is used in conjunction with noise-free complex refractive indices based on the dispersion theory. The peak positions in the simulated spectra are compared with transverse optic and longitudinal optic frequencies based on the macroscopic theory. The simulated peak intensities for the standing films are compared with the prediction based on the thin-film approximation. Furthermore, it is found from the spectral simulation for thin films on dielectric substrates that the peak intensity for a thin film may depend on the thickness and refractive index of the substrate. 相似文献
35.
Takekazu Ishida Kiichi Okuda Hidehito Asaoka Yukio Kazumata Kenji Noda Humihiko Takei 《Journal of Low Temperature Physics》1996,105(5-6):1165-1170
The interplane (cb) and intraplane (ab) anisotropy of untwinned YBa2 Cu307 single crystals has been investigated by means of the torque magnetometry. To extract the reversible and irreversible components, the torque was measured as a function of increasing angle as well as decreasing angle. The interplane irreversible torque irr shows two-fold peaks at c =90 ° and270 ° (of half width11 ° at77 K) due to the well-known intrinsic interplane pinning. A novel intrinsic pinning has been discovered in the intraplane irreversible torque, i.e., irr shows four-fold peaks of half width20° at77 K when a =0 °, 90 °, 180 ° and270 °. We argue that the intrinsic intraplane pinning comes from the four-fold nature of the gap parameter. 相似文献
36.
Hiroyuki Ishida Author Vitae Tomokazu Takahashi Author Vitae Author Vitae Hiroshi Murase Author Vitae 《Pattern recognition》2010,43(8):2799-2806
We propose a novel sequence alignment algorithm for recognizing handwriting gestures by a camera. In the proposed method, an input image sequence is aligned to the reference sequences by phase-synchronization of analytic signals which are transformed from original feature values. A cumulative distance is calculated simultaneously with the alignment process, and then used for the classification. A major benefit of this method is that over-fitting to sequences of incorrect categories is restricted. The proposed method exhibited higher recognition accuracy in handwriting gesture recognition, compared with the conventional dynamic time warping method which explores optimal alignment results for all categories. 相似文献
37.
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
38.
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
39.
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
40.