全文获取类型
收费全文 | 1732篇 |
免费 | 40篇 |
国内免费 | 12篇 |
专业分类
电工技术 | 76篇 |
综合类 | 3篇 |
化学工业 | 371篇 |
金属工艺 | 51篇 |
机械仪表 | 51篇 |
建筑科学 | 38篇 |
能源动力 | 47篇 |
轻工业 | 126篇 |
水利工程 | 5篇 |
石油天然气 | 2篇 |
无线电 | 195篇 |
一般工业技术 | 341篇 |
冶金工业 | 334篇 |
原子能技术 | 39篇 |
自动化技术 | 105篇 |
出版年
2023年 | 5篇 |
2022年 | 19篇 |
2021年 | 24篇 |
2020年 | 12篇 |
2019年 | 16篇 |
2018年 | 19篇 |
2017年 | 21篇 |
2016年 | 29篇 |
2015年 | 35篇 |
2014年 | 36篇 |
2013年 | 84篇 |
2012年 | 64篇 |
2011年 | 86篇 |
2010年 | 80篇 |
2009年 | 69篇 |
2008年 | 90篇 |
2007年 | 64篇 |
2006年 | 59篇 |
2005年 | 59篇 |
2004年 | 49篇 |
2003年 | 61篇 |
2002年 | 49篇 |
2001年 | 41篇 |
2000年 | 31篇 |
1999年 | 28篇 |
1998年 | 117篇 |
1997年 | 79篇 |
1996年 | 60篇 |
1995年 | 38篇 |
1994年 | 36篇 |
1993年 | 41篇 |
1992年 | 24篇 |
1991年 | 32篇 |
1990年 | 16篇 |
1989年 | 28篇 |
1988年 | 21篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 14篇 |
1984年 | 12篇 |
1983年 | 14篇 |
1982年 | 14篇 |
1981年 | 13篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1977年 | 12篇 |
1976年 | 8篇 |
1973年 | 4篇 |
1967年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有1784条查询结果,搜索用时 15 毫秒
91.
This paper proposes and demonstrates a numerical simulation method suitable to analyze the local damage and dynamic response of the structures composed of the reinforced concrete (RC) and/or the geological materials subjected to extremely severe loading by the energetic material like high explosives (HE). 相似文献
92.
Ryo Sakurai Shingo Ohno Shin‐ichi Kita Yoshitomo Masuda Reiji Hattori 《Journal of the Society for Information Display》2007,15(2):127-131
Abstract— Color displays and flexible displays that use electronic liquid powder have been developed. Novel types of color displays using either a colored powder or a color filter are discussed. We have also developed a flexible display with low‐cost substrate films with a high‐throughput roll‐to‐roll manufacturing method. These technologies enable a QR‐LPD to be widely used as an electronic‐paper display. 相似文献
93.
Naoki Mizuno Kazunori Ohno Ryunosuke Hamada Hiroyoshi Kojima Jun Fujita Hisanori Amano 《Advanced Robotics》2013,27(14):687-698
The firefighting robot system (FFRS) comprises several autonomous robots that can be deployed to fire disasters in petrochemical complexes. For autonomous navigation, the path planner should consider the robot constraints and characteristics. Specifically, three requirements should be satisfied for a path to be suitable for the FFRS. First, the path must satisfy the maximum curvature constraint. Second, it must be smooth for robots to easily execute the trajectory. Third, it must allow reaching the target location in a specific heading. We propose a path planner that provides smooth paths, satisfy the maximum curvature constraint, and allows a suitable robot heading. The path smoother is based on the conjugate gradient descent, and three approaches are proposed for this path planner to meet all the FFRS requirements. The effectiveness of these approaches is qualitatively and quantitatively evaluated by examining the generated paths. Finally, the path planner is applied to an actual robot to verify the suitability of the generated paths for the FFRS, and planning is applied to another type of robot to demonstrate the wide applicability of the proposed planner. 相似文献
94.
H. Soda A. Ichinose G. Motoyasu A. Ohno A. Mclean 《International Journal of Cast Metals Research》2013,26(2):95-102
AbstractUsing a heated double-channel mould, cored rods with pure tin as a clad material and Sn-Bi, Sn-Pb, and Sn-Zn eutectic alloys as core materials have been continuously cast. With precise control of casting variables, cored rods were successfully produced with a unidirectional structure for both core and clad materials. The effects of casting speed and mould exit temperature on cast structure were examined in an attempt to obtain an understanding of this new casting process. It was found that the dissolution of clad material occurs during casting, and the dissolution process is rapid and sensitive to the process variables. Excess dissolution of clad material leads to metal breakout. In order to reduce the dissolution, lower mould exit temperatures with faster casting speeds should be employed. 相似文献
95.
When human polymorphonuclear leukocytes (PMN) were attached to glass coverslips, cells always spread and formed reactive oxygen species prior to any experimental stimulation. To avoid this, a polyvinylidine chloride film was used as an inactive substance to place the cells. Cells engaged in phagocytosis on the film exhibited a specific H2O2-mediated luminol chemiluminescence (LCL) at the cell-particle interface; the cells stimulated with 12-O-tetradecanoylphorbol-13-acetate became aggregated and the LCL was observed at the cell-cell contact. These results corresponded well with those obtained by an electron microscopic H2O2-demonstration method. 相似文献
96.
Yamasaki T. Shima K. Komori S. Takata H. Tamura T. Asai F. Ohno T. Tomisawa O. Terada H. 《Solid-State Circuits, IEEE Journal of》1989,24(4):933-937
A VLSI-oriented variable-length pipeline structure for data-driven processors is presented. Ordinary inline pipelines have the problem of minimizing the average total processing time through the pipeline, since subdivision of a function along the pipeline is usually optimized for the most complex operations in spite of the fact that simpler operations need fewer stages. As a solution to this problem, a variable-length pipeline scheme in which data go through only the necessary stages according to information contained within is proposed. The scheme has been implemented on a test chip to verify performance. The chip demonstrated a minimum fall-through time (data transmission time from input to output) of 14.4 ns and a data transmission rate in the pipeline of 59 megaword/s (that is, 1/16.9 ns) as a first-in first-out (FIFO) store. By modifying the data transfer control and allocating the processing functions corresponding to the data interval of 16.9 ns, this scheme is applicable as a high-performance processing unit for data-driven processors 相似文献
97.
98.
This paper deals with an optimal part selection problem tominimize the expected cost, in an automated manufacturing system in which a flexible manufacturing cell produces different parts for several production lines. The optimal control problem is formulated as an undiscounted semi-Markov decision process. Properties of the optimal policy are analyzed. Moreover, sufficiency conditions are derived for the optimal policy to be of control iimit type. 相似文献
99.
Postdetection selection diversity reception for Nyquist pulse shaped quadrature differential PSK (QDPSK) signal transmissions is addressed. Average bit error rate (BER) performance with differential and coherent demodulation is analysed for multiple-branch diversity reception under slow multipath Rayleigh fading. Diversity effects in real fading environments are verified by 8 and 16 kbit/s transmissions at 1.45 GHz carrier frequency.<> 相似文献
100.
This work is concerned with the application of H/sub /spl infin// control with the generalized hold function (GHF) to track-following control of hard disk drives (HDDs). In HDDs, the sampling frequency is limited primarily by the fact that a high sampling frequency tends to decrease the available data storage capacity of the devices, since the position error signal (PES) must be stored on the disk. Under such conditions, GHF provides a possible way to enhance servo performance without requiring more PES data. We investigate its possibility, comparing the results with other conventional H/sub /spl infin// control design results, including continuous/discrete-time and single/multirate control. Our results show that this controller has better performance due to the nature of the control input of the GHF. 相似文献