Piwowarski W.,AGH University of Science and Technology |
Isakow Z.,EMAG Institute of Innovative Technologies |
Juzwa J.,EMAG Institute of Innovative Technologies
Archives of Mining Sciences | Year: 2015
The aim of this work is the estimation of the risk of mining damage occurrence, based on uncertain information regarding the impact of the concurrent processes of deformation and vibration. This problem concerns the experimental and theoretical description of the so-called critical phenomena occurring during the reaction mining area 虠 building object. Post-mining deformations of the rock mass medium and paraseismic vibrations can appear at a considerable distance from the sub-area of the mining operation - hence, the determination of the measures of their impacts is usually somewhat subjective, while the estimation of the mining damage based on deterministic methods is often insufficient. It is difficult to show the correlation between the local maximum of the impact of the velocity vector amplitude and the damage to the building - especially if the measures of interaction are not additive. The parameters of these impacts, as registered by measurements, form finite sets with a highly random character. Formally, it is adequate to the mapping from the probability space to the power set. For the purposes of the present study, the Dempster - Shafer model was used, where space is characterised by subadditive and superadditive measures. Regarding the application layer, the conclusions from the expert evaluations are assumed to be the values of random variables. The model was defined, and the risk of damage occurrence was estimated. © 2015 Archives of Mining Sciences.
Sobierajski W.,EMAG Institute of Innovative Technologies |
Kryca M.,EMAG Institute of Innovative Technologies |
Kozlowski A.,EMAG Institute of Innovative Technologies
Advances in Intelligent Systems and Computing | Year: 2014
EMAG Institute has specialized in working out the devices for qualitative control of coal. In most cases, they are radiometer appliances taking advantage of absorption or dispersion of gamma radiation of artificial radioactive source or natural radioactivity (ALFA and RODOS Ash Meters). Such methods not always ensure a required accuracy of measurement in case of mineralogical changes of a tested material. In 1980s a PYLOX Meter was worked out in EMAG that makes use of X-ray fluorescence for determining contents of noncombustible solids in mine dust from zones which protect against dust explosions. It was recognised that it is the only method which could allow to measure the quality of hard coal of a very diversified mineralogical contents. Therefore, it was decided to research aimed to determine the usability of PYLOX Meter for measurements of quality of coals from different coal mines and the possibility of improvement of metrological parameters by using semiconductor detectors. Research was conducted on samples originated from Uzbekistan and „Piast” Coal Mine. On the basis of received outcomes, it was stated that accurate determination of qualitative parameters of hard coal in the size grade of 0–3 mm is possible. The accuracy of order of 0,02% Aa (ash) and 0,002% St (sulphur) was obtained. © Springer International Publishing Switzerland 2014.