期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
Impact factors and improvement measures of enviroment quality in cleaning operating room
1
作者 陈小娣 《外科研究与新技术》 2011年第4期266-266,共1页
Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision ... Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision infection in cleaning operating room were retro- 展开更多
关键词 impact factors and improvement measures of enviroment quality in cleaning operating room
下载PDF
Intelligent Diagnosis of Short Hydraulic Signal Based on Improved EEMD and SVM with Few Low-dimensional Training Samples 被引量:10
2
作者 ZHANG Meijun TANG Jian +1 位作者 ZHANG Xiaoming ZHANG Jiaojiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期396-405,共10页
The high accurate classification ability of an intelligent diagnosis method often needs a large amount of training samples with high-dimensional eigenvectors, however the characteristics of the signal need to be extra... The high accurate classification ability of an intelligent diagnosis method often needs a large amount of training samples with high-dimensional eigenvectors, however the characteristics of the signal need to be extracted accurately. Although the existing EMD(empirical mode decomposition) and EEMD(ensemble empirical mode decomposition) are suitable for processing non-stationary and non-linear signals, but when a short signal, such as a hydraulic impact signal, is concerned, their decomposition accuracy become very poor. An improve EEMD is proposed specifically for short hydraulic impact signals. The improvements of this new EEMD are mainly reflected in four aspects, including self-adaptive de-noising based on EEMD, signal extension based on SVM(support vector machine), extreme center fitting based on cubic spline interpolation, and pseudo component exclusion based on cross-correlation analysis. After the energy eigenvector is extracted from the result of the improved EEMD, the fault pattern recognition based on SVM with small amount of low-dimensional training samples is studied. At last, the diagnosis ability of improved EEMD+SVM method is compared with the EEMD+SVM and EMD+SVM methods, and its diagnosis accuracy is distinctly higher than the other two methods no matter the dimension of the eigenvectors are low or high. The improved EEMD is very propitious for the decomposition of short signal, such as hydraulic impact signal, and its combination with SVM has high ability for the diagnosis of hydraulic impact faults. 展开更多
关键词 hydraulic impact fault improved EEMD end effect overshoot-undershoot SVM intelligent fault diagnosis short signal
下载PDF
Coefficient of restitution for particles impacting on wet surfaces: An improved experimental approach 被引量:4
3
作者 B. Cunger V. Salikov +4 位作者 S. Heinrich S. Antonyuk V.S. Sutkar N.G. Deen J.A.M. Kuipers 《Particuology》 SCIE EI CAS CSCD 2016年第2期1-9,共9页
The coefficient of restitution is widely used to characterize the energy dissipation rate in numerical simulations involving particle collisions. The challenge in measuring the coefficient of restitution is the strong... The coefficient of restitution is widely used to characterize the energy dissipation rate in numerical simulations involving particle collisions. The challenge in measuring the coefficient of restitution is the strong scatter seen in experimental data that results from varying particle properties, i.e. shape and surface roughness, and from imperfections in the experimental technique. To minimize this scattering, a novel experimental setup was developed based on two synchronized high-speed cameras capturing the collision behaviour of a particle in three dimensions. To measure the wet restitution coefficient, which describes particle impact in the presence of a liquid layer in the contact region, additional accuracy can be achieved by measuring the liquid layer thickness by a high-precision optical confocal sensor. The coefficient of restitution was measured for glass particles with two different diameters, at different relative velocities and liquid layer thicknesses, with a focus on small collision velocities and thin liquid layers, using both the improved (three dimensional) and the conventional (two dimensional) approaches to quantify the improvement of the new method's accuracy. 展开更多
关键词 Particle impact Coefficient of restitution Liquid layer Improved experimental setup
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部