Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas ...Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas emissions and associated cost.Payload variance causes significant differences in gross vehicle weights.Heavily loaded trucks travel slower up ramps than lightly loaded trucks.Faster trucks are slowed by the presence of slower trucks,resulting in‘bunching’,production losses and increasing fuel consumptions.This paper simulates the truck bunching phenomena in large surface mines to improve truck and shovel systems’efficiency and minimise fuel consumption.The study concentrated on completing a practical simulation model based on a discrete event method which is most commonly used in this field of research in other industries.The simulation model has been validated by a dataset collected from a large surface mine in Arizona state,USA.The results have shown that there is a good agreement between the actual and estimated values of investigated parameters.展开更多
The basic principle of spectral combination method is discussed,and the general expressions of the spectral weight and spectral combination of the united-processing of various types of gravimetric data are shown.What...The basic principle of spectral combination method is discussed,and the general expressions of the spectral weight and spectral combination of the united-processing of various types of gravimetric data are shown.What＇s more,based on degree error RMS of potential coefficients,the detailed expressions of spectral combination formulae and the corresponding spectral weights in the Earth＇s gravitational field model（EGM） determination using GOCE ＋ GRACE and CHAMP ＋ GRACE ＋ GOCE are derived.The fundamental situation that ulux-champ2013 s,tongji-GRACE01,go-cons-gcf-2-tim-r5 constructed respectively by CHAMP,GRACE,GOCE data and go-cons-gcf-2-dir-r5 constructed by syncretic processing of GRACE,GOCE and LAGEOS data are explained briefly,the degree error RMS,cumulative geoid height error and cumulative gravity anomaly error of these models are calculated.A syncretic model constructed from CHAMP,GRACE and GOCE data,which is expressed by champ ＋ grace ＋ goce,is obtained based on spectral combination method.Experimentation results show that the precision of CHAMP data model is the lowest in satellite-only models,so it is not needed in the determination of syncretic models.The GRACE data model can improve the GOCE data model in medium-long wavelength,so the overall precision of syncretic model can be improved.Consequently,as many types of gravimetric data as possible should be combined together in the data processing in order to strengthen the quality and reliability with widening scope and improve the precision and spatial resolution of the computational results.展开更多
故障树分析法(Fault Tree Analysis,FTA)是分析系统可靠性和安全性的一种重要方法,在各行业故障诊断中得到了广泛的应用。通过将故障树分析法和基于规则的专家系统相结合,对于发现卫星故障并成功维修以确保在轨卫星应用任务的正常运行...故障树分析法(Fault Tree Analysis,FTA)是分析系统可靠性和安全性的一种重要方法,在各行业故障诊断中得到了广泛的应用。通过将故障树分析法和基于规则的专家系统相结合,对于发现卫星故障并成功维修以确保在轨卫星应用任务的正常运行具有重要意义。文中建立了故障诊断框架,提出适合空间有效载荷故障知识获取及表示方法,可以极大地降低系统知识获取的难度,并提出载荷状态诊断的快速推理机制,实现了对实际任务中有效载荷状态故障的诊断。该诊断方法新颖,具有直观、非接触性、成本低、诊断速度快和正确性高的特点,能够极大地提高卫星运行控制工作的自动化程度、工作效率。展开更多
基金CRC MiningThe University of Queensland for their financial support for this study
文摘Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas emissions and associated cost.Payload variance causes significant differences in gross vehicle weights.Heavily loaded trucks travel slower up ramps than lightly loaded trucks.Faster trucks are slowed by the presence of slower trucks,resulting in‘bunching’,production losses and increasing fuel consumptions.This paper simulates the truck bunching phenomena in large surface mines to improve truck and shovel systems’efficiency and minimise fuel consumption.The study concentrated on completing a practical simulation model based on a discrete event method which is most commonly used in this field of research in other industries.The simulation model has been validated by a dataset collected from a large surface mine in Arizona state,USA.The results have shown that there is a good agreement between the actual and estimated values of investigated parameters.
基金supported by the National Natural Science Foundation of China(41304022)the National 973 Foundation(61322201,2013CB733303)the Youth Innovation Foundation of High Resolution Earth Observation(GFZX04060103-5-12)
文摘The basic principle of spectral combination method is discussed,and the general expressions of the spectral weight and spectral combination of the united-processing of various types of gravimetric data are shown.What＇s more,based on degree error RMS of potential coefficients,the detailed expressions of spectral combination formulae and the corresponding spectral weights in the Earth＇s gravitational field model（EGM） determination using GOCE ＋ GRACE and CHAMP ＋ GRACE ＋ GOCE are derived.The fundamental situation that ulux-champ2013 s,tongji-GRACE01,go-cons-gcf-2-tim-r5 constructed respectively by CHAMP,GRACE,GOCE data and go-cons-gcf-2-dir-r5 constructed by syncretic processing of GRACE,GOCE and LAGEOS data are explained briefly,the degree error RMS,cumulative geoid height error and cumulative gravity anomaly error of these models are calculated.A syncretic model constructed from CHAMP,GRACE and GOCE data,which is expressed by champ ＋ grace ＋ goce,is obtained based on spectral combination method.Experimentation results show that the precision of CHAMP data model is the lowest in satellite-only models,so it is not needed in the determination of syncretic models.The GRACE data model can improve the GOCE data model in medium-long wavelength,so the overall precision of syncretic model can be improved.Consequently,as many types of gravimetric data as possible should be combined together in the data processing in order to strengthen the quality and reliability with widening scope and improve the precision and spatial resolution of the computational results.
文摘故障树分析法(Fault Tree Analysis,FTA)是分析系统可靠性和安全性的一种重要方法,在各行业故障诊断中得到了广泛的应用。通过将故障树分析法和基于规则的专家系统相结合,对于发现卫星故障并成功维修以确保在轨卫星应用任务的正常运行具有重要意义。文中建立了故障诊断框架,提出适合空间有效载荷故障知识获取及表示方法,可以极大地降低系统知识获取的难度,并提出载荷状态诊断的快速推理机制,实现了对实际任务中有效载荷状态故障的诊断。该诊断方法新颖,具有直观、非接触性、成本低、诊断速度快和正确性高的特点,能够极大地提高卫星运行控制工作的自动化程度、工作效率。
