Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a po...Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a powered support in a mechanized Iongwall sublevel caving face. The logging system can be programmed for logging the data from the sensors at different logging intervals ranging from 16 h to 1 ms for logging variation in hydraulic pressures in legs and convergence of the support during progressive face advance. For recording dynamic loads, the data logger can be programmed to start fast logging, say at 10 ms intervals, when the pressure in a leg reaches a pre-specified threshold value, and continue fast logging until the pressure drops below this threshold value. This fast logging automatically stops when the pressure drops below this threshold value.展开更多
Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland woo...Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories： global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part （i.e., glued laminated timber-ceiling）. Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany.展开更多
文摘Described the development of an Intrinsically Safe System for continuous monitoring of load and convergence of powered roof supports installed at Iongwall faces. The system developed for monitoring of behavior of a powered support in a mechanized Iongwall sublevel caving face. The logging system can be programmed for logging the data from the sensors at different logging intervals ranging from 16 h to 1 ms for logging variation in hydraulic pressures in legs and convergence of the support during progressive face advance. For recording dynamic loads, the data logger can be programmed to start fast logging, say at 10 ms intervals, when the pressure in a leg reaches a pre-specified threshold value, and continue fast logging until the pressure drops below this threshold value. This fast logging automatically stops when the pressure drops below this threshold value.
文摘Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories： global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part （i.e., glued laminated timber-ceiling）. Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany.
