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   182篇
  免费   5篇
电工技术   8篇
化学工业   26篇
金属工艺   5篇
机械仪表   1篇
建筑科学   12篇
能源动力   12篇
轻工业   27篇
水利工程   3篇
石油天然气   1篇
无线电   15篇
一般工业技术   34篇
冶金工业   7篇
自动化技术   36篇
  2023年   1篇
  2022年   5篇
  2021年   7篇
  2020年   3篇
  2019年   7篇
  2018年   7篇
  2017年   5篇
  2016年   3篇
  2015年   7篇
  2014年   9篇
  2013年   14篇
  2012年   14篇
  2011年   18篇
  2010年   11篇
  2009年   13篇
  2008年   16篇
  2007年   13篇
  2006年   9篇
  2005年   2篇
  2004年   5篇
  2003年   1篇
  2002年   6篇
  2001年   2篇
  2000年   2篇
  1999年   1篇
  1998年   1篇
  1997年   3篇
  1989年   1篇
  1973年   1篇
排序方式: 共有187条查询结果,搜索用时 15 毫秒
41.
42.
43.
A method is presented for the assessment and calibration of the elastoplastic behaviour of FRP confined concrete. The method is based on the evaluation of permanent deformations from observed experimental deformations and theoretical elastic response of confined concrete. The inelastic response of concrete and the parameters of its mathematical modelling are investigated. Closed form expressions are produced to relate the model parameters to the mechanical properties of the material. A strain-hardening Drucker–Prager model is developed which simulates both the hardening and softening material response with reasonable agreement to the experimental observations. The predictive ability of the model is verified through comparisons to numerous published experimental data and analytical models.  相似文献   
44.
The MoveOn speech and noise database was purposely designed and implemented in support of research on spoken dialogue interaction in a motorcycle environment. The distinctiveness of the MoveOn database results from the requirements of the application domain—an information support and operational command and control system for the two-wheel police force—and also from the specifics of the adverse open-air acoustic environment. In this article, we first outline the target application, motivating the database design and purpose, and then report on the implementation details. The main challenges related to the choice of equipment, the organization of recording sessions, and some difficulties that were experienced during this effort, are discussed. We offer a detailed account of the database statistics, the suggested data splits in subsets, and discuss results from automatic speech recognition experiments which illustrate the degree of complexity of the operational environment.  相似文献   
45.
The results of an experimental and numerical investigation of an organic toluene droplet rising in a continuous aqueous phase are presented. The experiments were carried out in a small‐scale, high‐speed measuring unit. The numerical simulations were performed with the aid of the level set method implemented in the commercial CFD tool COMSOL Multiphysics 3.3a. Both measured and simulated terminal velocities are found to be in excellent agreement and match recent results. Moreover, the deviation from the spherical form is captured very well for different droplet sizes. Based on the experimental and numerical data obtained, an improvement of an existing terminal velocity correlation is suggested.  相似文献   
46.
框架结构的不完全弹塑性分析是一个非线性过程,按照假定的加载模式,利用荷载因子进行逐步加载。基于力学和数值方法,研究框架结构的极限承载力和变形能力。假定材料为理想弹塑性,并利用零长度塑性铰模拟塑性行为。该方法基于增量方程,类似于求解两个连续塑性铰之间的凸二次参数规划问题。利用虚荷载因子将凸二次参数规划转化为凸二次规划,并使用标准算法求解凸二次规划问题,可满足出现塑性铰的要求并自动判别塑性。该方法起初仅适用于纯弯作用,后延伸至弯矩-轴力共同作用。分别分析单调、变化、循环加载作用下的算例。整个过程稳定、可靠、高效,并比基于直接刚度法的交替位移方法更省时。  相似文献   
47.
A grid-oriented Biogenic Emission Model (BEM) has been developed to calculate Non-Methane Volatile Organic Compound (NMVOC) emissions from vegetation in high spatial and temporal resolutions. The model allows the emissions calculation for any modeling domain covering Europe on the basis of: 1) the U.S. Geological Survey 1-km resolution land-use database, 2) a land-use specific, monthly isoprene, monoterpene and Other Volatile Organic Compound (OVOC) emission potentials and foliar biomass densities database, 3) temperature and solar radiation data provided by the mesoscale meteorological model MM5. The model was applied for Europe in 30-km spatial resolution for the year 2003. The European total emissions for 2003 consist of 33.0% isoprene, 25.5% monoterpenes and 41.5% OVOC. BEM results are compared with those from the well-documented global Model of Emissions of Gases and Aerosols from Nature (MEGAN). The BEM total emissions compare well with the MEGAN ones. In July 2003, the results of both models agree within a factor of 1.2 for total isoprene emissions and within a factor of 2 for total monoterpene emissions. The comparison of the spatial distributions of the July 2003 isoprene and monoterpene emissions calculated with BEM and MEGAN shows that, in the greater part of the study area, the differences are below the current uncertainty limit for the estimation of spatially-resolved biogenic VOC emissions in Europe being equal to about ±600 kg km?2 month?1. Differences that are above this limit are found mainly in the eastern European countries for isoprene and in the Mediterranean countries for monoterpenes.  相似文献   
48.
In the world of business, quality improvement is of high importance for the manufacturing industries. Statistical process control via control charts provides an online monitoring of the product's characteristic. The adaptive feature is being widely used in the design parameters of a control chart, which allows at least one of them to change during the process monitoring. Specifically, a control chart is considered adaptive if at least one of the chart's parameters (sample size, sampling interval, or control limit coefficient) is allowed to change in real time on the basis of the actual values of the sample statistics. In this paper, recent developments in the design of multivariate adaptive control schemes are presented and discussed.  相似文献   
49.
Perovskite solar cells with a planar p-i-n device structure offer easy processability at low temperatures, suitable for roll-to-roll fabrication on flexible substrates. Herein we investigate different hole transport layers (solution processed NiOx, sputtered NiOx, PEDOT:PSS) in planar p-i-n perovskite solar cells using the triple cation lead halide perovskite Cs0.08(MA0.17FA0.83)0.92Pb(I0.83Br0.17)3 as absorber layer. Overall, reproducible solar cell performances with power conversion efficiencies up to 12.8% were obtained using solution processed NiOx as hole transport layer in the devices. Compared to that, devices with PEDOT:PSS as hole transport layer yield efficiencies of approx. 8.4%. Further improvement of the fill factor was achieved by the use of an additional zinc oxide nanoparticle layer between the PC60BM film and the Ag electrode.  相似文献   
50.
A 37‐year‐old hemodialysis patient appeared with unusual somnolence during 2 successive hemodialysis sessions. Blood gas analysis revealed hypercapnic respiratory failure and spirometry restrictive lung disease. After exclusion of other causes of restrictive lung disease with chest CT‐scan and cerebrum MRI, electrophysiological study revealed myopathy. Because besides lordosis and limb‐girdle gait the patient was ambulant the possibility of late‐onset Pompe's disease was set and confirmed with evaluation of α‐glucosidase activity and genetic analysis. Enzyme replacement therapy (ERT) with aglucosidase alfa was started. Due to inaccessibility of veins in the arm without the arteriovenous fistula, during the last 1 year, the patient received the ERT through the venous line of the hemodialysis circuit. Three years later the patient remains ambulant without the need of any assistant device and preserved his pulmonary function. This is the first described case of late‐onset Pompe's disease in a hemodialysis patient treated with ERT.  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