A distributed acoustic sensing(DAS)system is proposed and a data processing method for vibration is designed in this paper.The proposed DAS system is based on the Rayleigh scattering signal and utilizes phase-sensitiv...A distributed acoustic sensing(DAS)system is proposed and a data processing method for vibration is designed in this paper.The proposed DAS system is based on the Rayleigh scattering signal and utilizes phase-sensitive optical time-domain reflectometry(φ-OTDR)to demodulate the environmental vibration.It can collect the vibration information in railways and implement vibration classification based on the feature of sensed vibration signals.This system has been deployed in Guangzhou Shenzhen High-Speed Railway,and the experimental results validate its effectiveness.展开更多
A new predictive model for evaluating the vibration of a sawing machine was developed using a new rock classification system. The predictors are machine parameters and a rock sawability index. The new rock classificat...A new predictive model for evaluating the vibration of a sawing machine was developed using a new rock classification system. The predictors are machine parameters and a rock sawability index. The new rock classification system includes four major parameters of the rock： uniaxial compressive strength, abrasiv- ity index, mean MoWs hardness, and Young＇s modulus. The FAHP approach was used when determining the weights of these parameters by six decision makers. Two groups of carbonate rocks were sawn using a fully-instrumented laboratory sawing rig at different feed rates and depths of cut. During the sawing trials system vibration was monitored as a measure of saw performance. Then, a new statistical model was obtained by multiple regression on the machining parameters and the rock sawability index. The model is very useful for the evaluation of the system vibration, and for selecting suitable machining parameters, from a limited set of mechanical properties.展开更多
文摘A distributed acoustic sensing(DAS)system is proposed and a data processing method for vibration is designed in this paper.The proposed DAS system is based on the Rayleigh scattering signal and utilizes phase-sensitive optical time-domain reflectometry(φ-OTDR)to demodulate the environmental vibration.It can collect the vibration information in railways and implement vibration classification based on the feature of sensed vibration signals.This system has been deployed in Guangzhou Shenzhen High-Speed Railway,and the experimental results validate its effectiveness.
文摘A new predictive model for evaluating the vibration of a sawing machine was developed using a new rock classification system. The predictors are machine parameters and a rock sawability index. The new rock classification system includes four major parameters of the rock： uniaxial compressive strength, abrasiv- ity index, mean MoWs hardness, and Young＇s modulus. The FAHP approach was used when determining the weights of these parameters by six decision makers. Two groups of carbonate rocks were sawn using a fully-instrumented laboratory sawing rig at different feed rates and depths of cut. During the sawing trials system vibration was monitored as a measure of saw performance. Then, a new statistical model was obtained by multiple regression on the machining parameters and the rock sawability index. The model is very useful for the evaluation of the system vibration, and for selecting suitable machining parameters, from a limited set of mechanical properties.
