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排序方式: 共有913条查询结果,搜索用时 15 毫秒
11.
Jiangyan Zhang Tielong Shen Junichi Kako Shozo Yoshida 《International Journal of Control, Automation and Systems》2009,7(4):659-667
In this paper, the speed control problem of internal combustion engines is investigated based on mean-value engine models.
The dynamics of internal combustion engines is a complicated nonlinear system, and usually, it is difficult to know the exact
values of the physical parameters. First, a Lyapunov-based design method is shown without requiring the full information of
the physical parameters. Then, to improve transient performance, the design method is extended to several cases under different
operation conditions. Numerical simulation results are presented for comparing the proposed design methods. Finally, experiments
are conducted on an engine test bench and the results demonstrate the validity of the proposed design methods.
Recommended by Editorial Board member Myotaeg Lim under the direction of Editor Hyun Seok Yang. The authors are grateful to
Kai Zheng for his assistance of the model identification experiments.
Jiangyan Zhang received the B.E. and M.E. degrees in Electrical Engineering, Yanshan University, China, in 2005 and 2008, respectively.
Now, she is a Ph.D. candidate with the Department of Engineering and Applied Sciences, Sophia University, Tokyo, Japan. Her
current research interests include nonlinear system control theory and applications to powertrain system control.
Tielong Shen received the Ph.D. degree in Mechanical Engineering from Sophia University, Tokyo, Japan, March, 1992. From April 1992, he
has been a faculty member of the Chair of Control Engineering in Department of Mechanical Engineering, Sophia University,
where he currently serves as professor of the Department of Engineering and Applied Science. His research interests include
control theory and application in mechanical systems, power systems, and automotive powertrain. Currently, he is an Associate
Editor for the IEEE Control System Society Conference Editorial Board, and is serving as Associate Editor of Journal of Control
Theory and Applications, and the Regional Editor Asia-Pacific for International Journal of Modeling, Identification and Control
etc.
Junichi Kako received the B.E. degree from Nagoya Institute of Technology, Nagoya, Japan. He joined Toyota Motor Corporation, Tokyo, Japan
in 1989. He worked on various aspects of automotive powertrain control. From 1989 to 1994, he took part in the team for the
development of Laboratory Automation (LA) system, Engineering Office Automation (EOD) system, and embedded system of powertrain
control. During 1995–2001, he focused on the engine control systems in Powertrain Management Engineering Division. In 2002,
he was with Future Project Division in which he was responsible for the R&D of model-based engine control system. Currently,
he is developing engine control systems in the Powertrain Management Engineering Division, Toyota Motor Corporation.
Shozo Yoshida received the M.S. degree in Engineering from Kyoto University, Kyoto, Japan. He joined Toyota Motor Corporation, Tokyo, Japan
in 2000. From 2000 to 2004, he was with Future Project Division and worked on physical combustion modeling for Model-based
Control Development. Since 2005, he has been with the Powertrain Management Engineering Division Toyota Motor Corporation,
and is a member of the R&D of Model-based Engine Calibration. 相似文献
12.
Cyclic variability is a factor adversely affecting engine performance. In this paper a cyclic moving average regulation approach to cylinder pressure at top dead center (TDC) is proposed, where the ignition time is adopted as the control input. The dynamics from ignition time to the moving average index is described by ARMA model. With this model, a one-step ahead prediction-based minimum variance controller (MVC) is developed for regulation. The performance of the proposed controller is illustrated by experiments with a commercial car engine and experimental results show that the controller has a reliable effect on index regulation when the engine works under different fuel injection strategies, load changing and throttle opening disturbance. 相似文献
13.
Marc Karle Johannes W?hrle Junichi Miwa Nils Paust G��nter Roth Roland Zengerle Felix von Stetten 《Microfluidics and nanofluidics》2011,10(4):935-939
We demonstrate controlled transport of superparamagnetic beads in the opposite direction of a laminar flow. A permanent magnet
assembles 200 nm magnetic particles into about 200 μm long bead chains that are aligned in parallel to the magnetic field
lines. Due to a magnetic field gradient, the bead chains are attracted towards the wall of a microfluidic channel. A rotation
of the permanent magnet results in a rotation of the bead chains in the opposite direction to the magnet. Due to friction
on the surface, the bead chains roll along the channel wall, even in counter-flow direction, up to at a maximum counter-flow
velocity of 8 mm s−1. Based on this approach, magnetic beads can be accurately manoeuvred within microfluidic channels. This counter-flow motion
can be efficiently be used in Lab-on-a-Chip systems, e.g. for implementing washing steps in DNA purification. 相似文献
14.
In this paper, we present a new learning method using prior information for three-layer neural networks. Usually when neural
networks are used for identification of systems, all of their weights are trained independently, without considering interrelated
weights values. Thus, the training results are usually not good. The reason for this in that each parameter has its influence
on others during learning. To overcome this problem, we first give an exact mathematical equation that describes the relation
between weight values given a set of data conveying prior information. The we present a new learning method that trains part
of the weights and calculates the others using these exact mathematical equations. This method often a priori keeps the given
mathematical structure exactly the same during learning; in other words, training is done so that the network follows a predetermined
trajectory. Numerical computer simulation results are provided to support this approach.
This work was presented, in part, at the Fourth International Symposium on Artificial Life and Robotics, Oita, Japan, January
19–22, 1999. 相似文献
15.
Junichi Takahashi Masahiko Shimada Kouta Iwasaki Hisanori Yaname 《Journal of Electroceramics》2006,17(1):95-98
Single crystals of Bi and Cu-doped Ca3Co2O6were synthesized in a molten K2CO3flux. Using an obtained single crystal of (Ca0.985(5)Bi0.015(5))3(Co0.990(3)Cu0.010(3))2O6elongated to the c-axis direction of the crystal structure, the electric resistivity (ρ) and Seebeck coefficient (S) were measured from room temperature to over 1000 K in air. The single crystal showed p-type semiconducting behavior with ρ values of 1.8 Ω cm at 303 K and 0.017 Ω cm at 1000 K. The S values were +254 μ VK− 1 at 325 K, +360 μ VK− 1 at 420 K, and +214 μ VK− 1 at 1000 K. The power factor (S
2
ρ
− 1) increased with an increase of temperature and attained 2.70 × 10− 4 Wm− 1K− 2 at 1000 K. 相似文献
16.
研究了粉末冶金机械零件使用的烧结材料的杨氏模量、切变模量及泊松比与孔隙度的关系.制备了三种钢粉,在不同条件下进行了压制、烧结与热处理.孔隙度对杨氏模量、切变模量及泊松比的影响最大.特别是泊松比还受孔隙形状的影响,而孔隙形状随粉末类型、烧结温度与烧结气氛及热处理条件而变化.对于大部分实际应用的粉末组成来说,烧结气氛对经烧结和热处理后材料的泊松比影响不大.对于部分预合金化粉末(Fe4%Ni1.5%Cu0.5%Mo)+0.8%石墨,只有在孔隙度低于20%时,烧结温度对泊松比与孔隙度的关系才有影响.在这种情况下.提出了烧结与热处理试样泊松比与孔隙度关系的较简单近似方程:在烧结温度1 423K下,v=0.300-0.266P+0.579P2;在烧结温度1 523K下,v=0.304-0.264P+0.548P2. 相似文献
17.
In-situ analysis for SiC bulk single crystal growth was reported using vertical X-ray diffractometer system. A furnace for SiC sublimation growth combined with the XRD system which possessed three kinds of functions including topography, rocking curve measurement and crystal growth rate monitoring was developed. These functions could contribute as a powerful tool finding the optimum growth condition by dynamic observation in the crucible. In this study, the in-situ X-ray topographs succeeded to capture dynamic elongation of defects and dislocation generated in the SiC growing crystals. The in-situ rocking curve measurement reviled appearance of mosaic structure in the SiC crystal grown with high growth rate. The in-situ growth rate monitoring also succeeded very precisely using the direct X-ray beam absorption. On the base of findings and facts obtained by the in-situ observations, the importance for the SiC growth was discussed. 相似文献
18.
Shunpei Yamazaki Takuya Hirohashi Masahiro Takahashi Shunsuke Adachi Masashi Tsubuku Junichi Koezuka Kenichi Okazaki Yohsuke Kanzaki Hiroshi Matsukizono Seiji Kaneko Shigeyasu Mori Takuya Matsuo 《Journal of the Society for Information Display》2014,22(1):55-67
Our crystalline In–Ga–Zn oxide (IGZO) thin film has a c‐axis‐aligned crystal (CAAC) structure and maintains crystallinity even on an amorphous base layer. Although the crystal has c‐axis alignment, its a‐axis and b‐axis have random arrangement; moreover, a clear grain boundary is not observed. We fabricated a back‐channel‐etched thin‐film transistor (TFT) using the CAAC‐IGZO film. Using the CAAC‐IGZO film, more stable TFT characteristics, even with a short channel length, can be obtained, and the instability of the back channel, which is one of the biggest problems of IGZO TFTs, is solved. As a result, we improved the process of manufacturing back‐channel‐etched TFTs. 相似文献
19.
Junichi Karasawa Taku Aoyama Takeshi Kijima Eiji Natori Tatsuya Shimoda 《Integrated ferroelectrics》2013,141(1):137-145
A high-pressure annealing was applied to a post-annealing process for sol-gel derived PZT thin films. The squareness of D-E hysteresis curves changes depending on both total pressure and oxygen concentration. Moreover, the change follows the product of the total pressure and the oxygen concentration, which correspond to oxygen partial pressure PO2. Where the PO2 is higher than 0.03 MPa, few of the squareness of the hysteresis curve are excellent. The squareness of the hysteresis curves dramatically improve as the PO2 decreases. Where the PO2 is lower than 0.01 MPa, the squareness deteriorates slightly. These changes in the D-E hysteresis curves are thought to be explained by the generation of lead and oxygen vacancies as a function of the PO2. 相似文献
20.
Takayanagi J. Nishizawa N. Sugiura T. Yoshida M. Goto T. 《Quantum Electronics, IEEE Journal of》2006,42(3):287-291
We present an all-fiber system for generating pedestal-free 22-fs ultrashort pulses with a single-peak spectrum. High-power Raman soliton pulses and a normally dispersive highly nonlinear fiber are used to generate a smooth, broadened single-peak spectrum. Then, the higher order dispersion is compensated for using a hybrid fiber composed of a reverse-dispersion fiber and a standard single-mode fiber, which allows pedestal-free ultrashort pulses to be successfully generated. To our knowledge, this is the first demonstration of pedestal-free 20-fs-class ultrashort pulse generation without spectral distortion using an all-fiber configuration. 相似文献