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Number of results: 8
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Abstract

This paper presents mathematical models enabling the calculation of the distribution and patterns of methane inflow to the air stream in a longwall seam being exploited and spoil on a longwall conveyor, taking into account the variability of shearer and conveyor operation and simulation results of the mining team using the Ventgraph-Plus software. In the research, an experiment was employed to observe changes in air parameters, in particular air velocity and methane concentration in the Cw-4 longwall area in seam 364/2 at KWK Budryk, during different phases of shearer operation in the area of the mining wall in methane hazard conditions. Presented is the method of data recording during the experiment which included records from the mine’s system for automatic gasometry, records from a wireless system of eight methane sensors installed in the end part of the longwall and additionally from nine methane anemometers located across the longwall on a grid. Synchronous data records obtained from these three independent sources were compared against the recording the operating condition of the shearer and haulage machines at the longwall in various phases of their operation (cleaning, cutting). The results of the multipoint system measurements made it possible to determine the volume of air and methane flow across the longwall working, and, consequently, to calculate the correction coefficients for determining the volume of air and methane from measurements of local air velocity and methane concentration. An attempt was made to determine the methane inflow from a unit of the longwall body area and the unit of spoil length on conveyors depending on the mining rate. The Cw-4 longwall ventilation was simulated using the data measured and calculated from measurements and the simulation results were discussed.

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Authors and Affiliations

Wacław Dziurzyński
ORCID: ORCID
Teresa Palka
Andrzej Krach
ORCID: ORCID
Stanisław Wasilewski
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Abstract

Inflow areas of Poles to Germany after the EU enlargement in 2004. The aim of this article is to analyse one of the important components of contemporary Polish-German relationships, i.e. migration of Polish population to Germany. The scale and dynamics of this process have intensified since Poland’s accession to the European Union in 2004 and full opening of the German labour market to Polish citizens in 2011. The article focuses on spatial consequences of Polish-German migration seen from the perspective of the immigrant country. Its conclusions are based on unique statistical data and cartographic materials.
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Authors and Affiliations

Tadeusz Stryjakiewicz
Piotr Sosiński
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Abstract

The aim of this study was to analyze the influence of water movement on both qualita-tive and quantitative occurrence of macrophytes in lakes. We studied four lakes differentiated in respect of water supply (two flow and two inflow).The investigation included: determination of the buffer zones of lakes, analysis of land use forms and layout of the buffer zone, floristic charac-teristic of lakes littoral, characteristic of phytolittoral types, analysis of physical and chemical parameters of lakes. The buffer zone of the flow lakes was dominated by farmland, but there was no land meadow. In the inflow lakes co-dominated fields and forests in the buffer zone. The in-flow lakes characterized by greater species diversity, density and biomass of emergent macro-phytes. In all investigated lakes, in the zone of water supply, analyzed features of macrophytes, and selected chemical parameters of water, reached the highest value.
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Authors and Affiliations

Andrzej Demetraki-Paleolog
Joanna Sender
Magda Garbowski
Marcin Kolejko
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Abstract

This paper presents an identification method of pollution inflow directions based on the circular graphs of percentiles of pollution concentrations and the possibilities of applying these graphs to estimation of pollutant emission. Based on these graphs of particulate matter concentration recorded in winter and summer seasons, the inflows of dust from the direction of fly ash landfill have been compared for summer and winter periods. This analysis enables to assess the relation of concentrations of pollution from secondary particulate matter suspension to concentrations of pollution generated by other sources. This paper also argues that the 24-hours concentrations, though commonly used, may prove to be an indicator of minor importance to assess air pollution status. On the one hand, excessive 24-hours concentrations impede the identification of the polluter, on the other hand, concentrations generally within permissible limits may occasionally peak dangerously at some sources. As an example, an existing case and a numerical experiment have been presented.
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Authors and Affiliations

Czesław Kliś
Marek Matejczyk
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Abstract

In this paper a method of analyzing air pollution data in an optional automatic measuring station, allowing for identification of the directions of the pollution inflow has been presented. The method is based on four parameters provided by the measuring station: pollution concentration, wind direction, wind speed and fluctuation of the wind directions. For the description of the wind direction fluctuation in 30-minutes' periods a coefficient of relative turbulent diffusion rr(3, 30) was used, which is defined as a deviation of 3-minutes' wind vectors from the 30-minutes' vector. The presented method was applied for identification of the inflow directions of SO2 and NO2 using the measuring data from a telemetric system OPSIS at the Institute for Ecology of Industrial Areas in Katowice-Załęże.
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Authors and Affiliations

Czesław Kliś
Mieczysław Żeglin
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Abstract

The aim of the study was to evaluate the possibility of applying different methods of data mining to model the inflow of sewage into the municipal sewage treatment plant. Prediction models were elaborated using methods of support vector machines (SVM), random forests (RF), k-nearest neighbour (k-NN) and of Kernel regression (K). Data consisted of the time series of daily rainfalls, water level measurements in the clarified sewage recipient and the wastewater inflow into the Rzeszow city plant. Results indicate that the best models with one input delayed by 1 day were obtained using the k-NN method while the worst with the K method. For the models with two input variables and one explanatory one the smallest errors were obtained if model inputs were sewage inflow and rainfall data delayed by 1 day and the best fit is provided using RF method while the worst with the K method. In the case of models with three inputs and two explanatory variables, the best results were reported for the SVM and the worst for the K method. In the most of the modelling runs the smallest prediction errors are obtained using the SVM method and the biggest ones with the K method. In the case of the simplest model with one input delayed by 1 day the best results are provided using k-NN method and by the models with two inputs in two modelling runs the RF method appeared as the best.

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Authors and Affiliations

Bartosz Szeląg
Lidia Bartkiewicz
Jan Studziński
Krzysztof Barbusiński

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