全文获取类型
收费全文 | 1195篇 |
免费 | 15篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 29篇 |
综合类 | 1篇 |
化学工业 | 223篇 |
金属工艺 | 51篇 |
机械仪表 | 35篇 |
建筑科学 | 11篇 |
能源动力 | 35篇 |
轻工业 | 87篇 |
水利工程 | 12篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 123篇 |
一般工业技术 | 189篇 |
冶金工业 | 352篇 |
原子能技术 | 18篇 |
自动化技术 | 46篇 |
出版年
2023年 | 3篇 |
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 5篇 |
2019年 | 8篇 |
2018年 | 11篇 |
2017年 | 4篇 |
2016年 | 12篇 |
2015年 | 9篇 |
2014年 | 18篇 |
2013年 | 42篇 |
2012年 | 41篇 |
2011年 | 55篇 |
2010年 | 39篇 |
2009年 | 43篇 |
2008年 | 51篇 |
2007年 | 41篇 |
2006年 | 26篇 |
2005年 | 34篇 |
2004年 | 24篇 |
2003年 | 30篇 |
2002年 | 35篇 |
2001年 | 26篇 |
2000年 | 28篇 |
1999年 | 31篇 |
1998年 | 119篇 |
1997年 | 82篇 |
1996年 | 57篇 |
1995年 | 38篇 |
1994年 | 25篇 |
1993年 | 35篇 |
1992年 | 19篇 |
1991年 | 21篇 |
1990年 | 13篇 |
1989年 | 23篇 |
1988年 | 15篇 |
1987年 | 13篇 |
1986年 | 13篇 |
1985年 | 17篇 |
1984年 | 14篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 8篇 |
1976年 | 11篇 |
1974年 | 5篇 |
1967年 | 2篇 |
排序方式: 共有1214条查询结果,搜索用时 0 毫秒
1.
2.
S. Arimoto T. Nakayama 《Mechatronics, IEEE/ASME Transactions on》1996,1(2):168-180
Dynamics and control of nonlinear mechanical systems and advanced mechatronic systems can be investigated more vividly and efficiently by using corresponding nonlinear position-dependent circuits that describe Lagrange's equations of motions and interactions with objects or/and task environments. Such expressions of Lagrange's equations via nonlinear circuits are indebted to lumped-parameter discretization of mechanical systems as a set of rigid bodies through equations of motion due to Newton's second law. This observation is quite analogous to validity of electric circuits that can be derived as lumped parameter versions of Maxwell's equations of electromagnetic waves. Couplings of nonlinear mechanical circuits with electrical circuits through actuator dynamics are also discussed. In such electromechanical circuits the passivity should be a generalization of impedance concept in order to cope with general nonlinear position-dependent circuits and play a crucial role in their related motion control problems. In particular, it is shown that the passivity as an input-output property gives rise to a necessary and sufficient characterization of H/sub /spl infin//-tuning for disturbance attenuation of robotic systems, which can give another system theoretic interpretation of the energy conservation law. 相似文献
3.
T. Tanaka H. Nakayama K. Kimura 《Fatigue & Fracture of Engineering Materials & Structures》1985,8(1):13-22
The impact fatigue crack growth characteristics of a low carbon steel and an aluminium alloy were studied. An impact fatigue testing machine of the Hopkinson bar type was used in these experiments to conduct a series of crack growth tests under simple impact stresses. The following characteristics of impact fatigue crack growth behaviour were revealed: (1) crack growth rate is higher in impact fatigue than in non-impact fatigue; (2) crack opening ratio in impact fatigue takes a higher value than in non-impact fatigue; (3) crack tip plastic zone size is smaller in impact fatigue than in non-impact fatigue. 相似文献
4.
This paper analyzes the factors underpinning transboundary Environmental Impact Assessment (EIA) methodologies through an examination of the Navigation Channel Improvement Project of the Lancang-Mekong River from China-Myanmar Boundary Marker 243 to Ban Houei Sai of Laos. A comparison of the project's expected and reported transboundary impacts shows that the EIA failed to predict a number of adverse impacts, including social and economic impacts. The restricted scale and scope of the transboundary impact assessment (TIA) is probably due to certain fundamental restrictions on how the EIA was conducted. The case study highlights the importance of public involvement (including advance notification) and adequate regulatory frameworks or guidelines in the EIA and TIA processes. 相似文献
5.
Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献
6.
7.
8.
The present paper deals with the finite element analysis of two-dimensional two-layer density flows in a gravitational field. A fluid in each layer is replaced with a large number of discrete particles, and the motion and deformation of each layer is represented by moving those particles in a Lagrangian manner. The velocity distribution in the whole fluid region is given as the finite element solution of the Navier-Stokes equations and the equation of continuity. In the finite element calculation, free-slip conditions are used on solid wall boundaries because no-slip conditions may cause sticking of some particles to walls. Then, a new technique for the implementation of free-slip conditions on arbitrary curved boundaries is presented. As numerical examples, density flows in a rectangular closed container and Rayleigh-Taylor instability in the container with a circular cross-section have been computed. 相似文献
9.
Takiguchi Y. Nakayama M. Kubota M. Yamazaki J. 《Broadcasting, IEEE Transactions on》1998,44(1):123-130
Two kinds of TV cameras have been developed that are capable of showing the wavelengths of ultraviolet, infrared, and visible light by means of a false color method. One is sensitive to wavelengths from 250 to 650 nm (ultraviolet to yellow). It can simulate the color vision of the honey bee and other insects, reproducing the nectar guide of a flower or displaying the sex of a cabbage white moth, which is indistinguishable to the naked eye. The other is sensitive to a wider wavelength of 250 to 1,050 nm (ultraviolet to near infrared). According to the filter selected, it obtains not only visual images of invisible light information but also pictures same as those from an ordinary color camera. These TV cameras can be applied in many fields, including science, art, medicine, and industry 相似文献
10.
Lee S.B. Nakayama K. Matsui T. Ozaki M. Yoshino K. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2002,9(1):31-38
Silica particles dispersed in liquid crystals exhibit a novel behavior such as a unique migrating behavior and alignment. These characteristics are found to depend on the size of the nanoparticles, the surface state of nanoparticles, the liquid crystal (LC) phases, the amplitude and the frequency of applied voltage. These are discussed in terms of anisotropic particle-particle and particle-LC molecules interactions in the anisotropic environment of liquid crystal matrix 相似文献