首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   127篇
  免费   10篇
电工技术   3篇
化学工业   25篇
机械仪表   5篇
建筑科学   1篇
能源动力   1篇
轻工业   11篇
水利工程   1篇
无线电   46篇
一般工业技术   15篇
冶金工业   8篇
自动化技术   21篇
  2023年   2篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   2篇
  2018年   7篇
  2017年   2篇
  2016年   8篇
  2015年   3篇
  2014年   5篇
  2013年   10篇
  2012年   6篇
  2011年   4篇
  2010年   7篇
  2009年   12篇
  2008年   5篇
  2007年   7篇
  2006年   4篇
  2005年   6篇
  2004年   4篇
  2003年   4篇
  2002年   2篇
  2001年   4篇
  2000年   1篇
  1999年   5篇
  1998年   4篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1993年   1篇
  1992年   1篇
  1990年   4篇
  1989年   1篇
  1988年   2篇
  1984年   2篇
  1981年   1篇
排序方式: 共有137条查询结果,搜索用时 15 毫秒
131.
A new proposed robust FM demodulator (RFMD) is a simplified version of the recently reported demodulator (FMD) [1] which improves FM system interference immunity. The RFMD is applied to combat the adjacent channel interference and its improvement factor is only negligibly smaller than that of the FMD.  相似文献   
132.
Contribution of low load cycles to fatigue damage in 0.15 %C steel The S‐N curve of 0.15 %C steel shows an endurance limit. Two‐step variable amplitude loading experiments serve to investigate the influence of numerous cycles below the endurance limit on fatigue damage. If high stress amplitudes of the loading sequences are more than approx. 15 % above the endurance limit, low load cycles contribute significantly to fatigue damage. Investigations of fatigue crack propagation under two‐step variable amplitude loading show accelerated crack growth caused by low load cycles. If high stress amplitudes of the two‐step sequences are less than 15 % above the endurance limit, beneficial influences of numerous low load cycles are found. Under these conditions, the material can sustain far greater numbers of load cycles than predicted by Miner damage accumulation calculation. Fatigue crack growth studies show that under these conditions for the high load numerous low load cycles lead to stop of the crack propagation.  相似文献   
133.
The chemical composition, colour and texture of fresh berries from three rabbiteye (‘Climax’, ‘Premier’ and ‘Tifblue’) and two highbush (‘Bluecrop’ and ‘Jersey’) blueberry cultivars were measured. Shear (482 vs 290 N), compression (6.50 vs 3.96 N) and puncture forces (1.48 and 0.85 vs 0.81 and 0.43 N) were higher (P ≤ 0.05) for rabbiteye than for highbush cultivars. Shear for ‘Bluecrop’ blueberries averaged 254 N, whereas for ‘Climax’ it was 565 N. The puncture force required to penetrate the skin was lower for ‘Bluecrop’ (0.78 N) and ‘Jersey’ (0.83 N) and higher for ‘Climax’ (1.71 N). However, sensory panellists found no differences (P > 0.05) in colour, flavour or skin toughness among the five cultivars. ‘Climax’ was rated lower in seediness. Rabbiteye cultivars contained more fibre and complex polysaccharides than highbush cultivars. These differences in complex carbohydrates that make up the cell wall layers may contribute to the toughness of rabbiteye cultivars and their possible longer fresh shelf‐life, though taste panellists did not find this toughness objectionable. Copyright © 2005 Society of Chemical Industry  相似文献   
134.
135.
The assembly of molecular automata that perform increasingly complex tasks, such as game playing, presents an unbiased test of molecular computation. We now report a second-generation deoxyribozyme-based automaton, MAYA-II, which plays a complete game of tic-tac-toe according to a perfect strategy. In silicon terminology, MAYA-II represents the first "medium-scale integrated molecular circuit", integrating 128 deoxyribozyme-based logic gates, 32 input DNA molecules, and 8 two-channel fluorescent outputs across 8 wells.  相似文献   
136.
This article investigates the composite adaptive fuzzy finite-time prescribed performance control issue of switched nonlinear systems subject to the unknown external disturbance and performance requirement. First, by utilizing the compensation and prediction errors, the piecewise switched composite parameter update law is employed to improve the approximation accuracy of the unknown nonlinearity. Then, the improved fractional-order filter and error compensation signal are introduced to cope with the influences caused by the explosive calculation and filter error, respectively. Meanwhile, the effect of the compound disturbances consisting of the unknown disturbances and approximation errors is reduced appropriately by designing the piecewise switched nonlinear disturbance observer. Moreover, stability analysis results prove that the proposed preassigned performance control scheme not only ensures that all states of the closed-loop system are practical finite-time bounded, but also that the tracking error converges to a preassigned area with a finite time. Ultimately, the simulation examples are given to demonstrate the effectiveness of the proposed control strategy.  相似文献   
137.
The problem of hybrid-driven fuzzy filtering for nonlinear semi-linear parabolic partial differential equation systems with dual cyber attacks is investigated. First, a Takagi-Sugeno (T-S) fuzzy model is employed to reconstruct the original nonlinear systems. Second, a hybrid-driven mechanism is applied for filter design to balance the systems' performance and the limited network resource consumption under dual cyber attacks composed of deception and denial of service attacks. Based on the Lyapunov direct method, sufficient conditions to guarantee the stability of the augmented system are obtained, and the parameters of the designed filter are earned with explicit form. Finally, a simulation example with robust analysis and comparative analysis is provided to illustrate the effectiveness of the proposed method.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号