The diesel particulate matter(DPM) emission from diesel powered equipment in underground mines can cause health hazards including cancer to the miners. The understanding of the DPM propagation pattern under realistic ...The diesel particulate matter(DPM) emission from diesel powered equipment in underground mines can cause health hazards including cancer to the miners. The understanding of the DPM propagation pattern under realistic mining condition is required for selecting proper DPM control strategies and to improve working practices in underground mines. In this paper, three dimensional simulations of DPM emission from the exhaust tail pipe of a load-haul-dump(LHD) vehicle and its subsequent distribution inside an isolated zone in the typical underground mine are carried out using two different solution models available in Ansys Fluent. The incoming fresh air into the isolated zone is treated as a continuous phase and DPM is treated either as a continuous phase(gas) or as a secondary discrete phase(particle). Species transport model is used when DPM is treated as gas and discrete phase model is used when DPM is assumed to behave like a particle. The distributions of DPM concentration inside the isolated zone obtained from each method are presented and compared. From the comparison results, an accurate and economical solution technique for DPM evaluation can be selected.展开更多
A 3D road geometry reconstruction system using on-board camera for vehicle driver assistance is developed. Given calibration of the camera, 3D structure of the road in front of the vehicle is built via multiple vanish...A 3D road geometry reconstruction system using on-board camera for vehicle driver assistance is developed. Given calibration of the camera, 3D structure of the road in front of the vehicle is built via multiple vanishing points estimation and local parallelism of the road. The road will be modeled as a piecewise linear approximation of space curve. Vanishing points are estimated through line grouping and histogram method in the image. The system is not restricted to the roads which lie on 2D plane, but also is capable of recovering a full 3D geometry. The ambiguity of distance (scale) is resolved by usage of parallel line segnents an the road image.展开更多
基金financial support provided by the Western US Mining Safety and Health Training&Translation Center by the National Institute for Occupational Safety and Health(NIOSH)
文摘The diesel particulate matter(DPM) emission from diesel powered equipment in underground mines can cause health hazards including cancer to the miners. The understanding of the DPM propagation pattern under realistic mining condition is required for selecting proper DPM control strategies and to improve working practices in underground mines. In this paper, three dimensional simulations of DPM emission from the exhaust tail pipe of a load-haul-dump(LHD) vehicle and its subsequent distribution inside an isolated zone in the typical underground mine are carried out using two different solution models available in Ansys Fluent. The incoming fresh air into the isolated zone is treated as a continuous phase and DPM is treated either as a continuous phase(gas) or as a secondary discrete phase(particle). Species transport model is used when DPM is treated as gas and discrete phase model is used when DPM is assumed to behave like a particle. The distributions of DPM concentration inside the isolated zone obtained from each method are presented and compared. From the comparison results, an accurate and economical solution technique for DPM evaluation can be selected.
基金supperted by the National ITIndustry Promotion Agency(NIPA)(NIPA-2010-C1090-1021-0010),KOREA
文摘A 3D road geometry reconstruction system using on-board camera for vehicle driver assistance is developed. Given calibration of the camera, 3D structure of the road in front of the vehicle is built via multiple vanishing points estimation and local parallelism of the road. The road will be modeled as a piecewise linear approximation of space curve. Vanishing points are estimated through line grouping and histogram method in the image. The system is not restricted to the roads which lie on 2D plane, but also is capable of recovering a full 3D geometry. The ambiguity of distance (scale) is resolved by usage of parallel line segnents an the road image.