13 research outputs found

    Measurement of Electromagnetic Field Component Emissions as a Precursor of Emerging Hazard in Coal Mines, Journal of Telecommunications and Information Technology, 2019, nr 4

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    The article presents the results of research concerning electromagnetic (EM) field emitted by rocks during the process of their destruction. The paper describes a measuring stand designed for subjecting rock samples to axial crushing. During the destruction of rock samples, both components of the electromagnetic field emitted by the rock were recorded. The paper presents the results of research on hard coal samples, presenting the obtained time domain waveforms and frequency spectrum of the emitted EM field components. Further potential uses of tests concerned with EM emitted by rocks are determined. Applications registering EM field in mine environments may provide an early mine collapse warning

    Landslides' electromagnetic emission measurement

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    In this paper electromagnetic phenomena occurring during landslides activity are presented, and their measurement method analyzed in details. The authors propose an original system for measuring both continuous and pulsed electromagnetic emission of landslides. For such measurements boreholes must be drilled in the landslide. It is essential that the tubing constituting the borehole’s lining must be made of a material which does not attenuate electromagnetic field. The results of electromagnetic emission examinations of the Jaroszow landslide in south-western Poland, near Wroclaw are presented too in this paper

    Measuring Electromagnetic Emissions from Active Landslides, Journal of Telecommunications and Information Technology, 2015, nr 2

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    The paper describes the mechanism of electromagnetic emission generation in active landslides and measuring techniques. Special attention is given to electromagnetic emission fields. The author proposes an original system for measuring both continuous and pulsed magnetic emission of land-slides. For such measurements boreholes must be drilled in the landslide. It is essential that the tubing constituting theborehole’s lining be made of a material which does not attenuate magnetic fields. Besides its primary function, i.e. the registration of landslide magnetic field activity, the system can be used for the structural inhomogeneity of rock strata examination subjected to considerable stresses. The results of examinations of active and inactive landslide in Poland are presented. The post-extraction cave in the SMZ Jelsava Mine in Jelsava, Slovakia, is presented too

    Autonomous Instrumentation for Measuring Spontaneous Electromagnetic Emissions in Mining, Journal of Telecommunications and Information Technology, 2020, nr 4

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    This article presents the design of an innovative receiver capable of identifying electric and magnetic components of electromagnetic fields. The receiver senses and records electromagnetic disturbances generated as mine tunnels collapse. It offers excellent operating specification and the ability to sense and log magnetic and electrical component strength values in real time. The paper analyzes the data obtained with the use of a system installed in a working mine and attempts to determine hazards resulting from increased rock stress levels that, cause spontaneous EM emission

    Szybka analiza zaburzeń krótkotrwałych. Opracowany w Instytucie Łączności Analizator ACA-4c. Telekomunikacja i Techniki Informacyjne, 2014, nr 3-4

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    W artykule opisano opracowany i wdrożony do produkcji w Instytucie Łączności analizator zakłóceń krótkotrwałych ACA-4c, pozwalający na skrócenie czasu badań wyrobów w zakresie emisji trzasków. Urządzenie to umożliwia automatyczne wykonywanie kompleksowej analizy trzasków, równocześnie dla czterech znormalizowanych częstotliwości i na obu poziomach analizy. Zbudowane zostało w oparciu o bogate doświadczenie Instytutu i spełnia wszystkie wytyczne zawarte w normach

    Research Concerning Electro magnetic Emissions from Residential On-grid PV Systems, Journal of Telecommunications and Information Technology, 2021, nr 4

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    The paper presents the results of grid power quality tests and wide frequency electromagnetic radiation level tests to which home power networks with photovoltaic systems have been subjected. The said results are meaningful from the point of view of safety and compatibility of electrical devices and the power supply system they are connected to. The tests covered stability of phase voltage and its frequency, harmonic level flicker, as well as RF radiated and emission levels. The measurements performed provide an answer to the question concerning the level of compliance of randomly selected home-installed PV systems with applicable recommendations and regulations concerning electromagnetic compatibility. The ability to meet the applicable standards translates into the health and safety of building inhabitants, which is the ultimate goal. Legal regulations concerning electromagnetic compatibility of renewable energy sources are consistent throughout the entire European Unio

    Autonomous Instrumentation for Measuring Electromagnetic Radiation from Rocks in Mine Conditions—A Functional Analysis

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    This paper analyses the function of an innovative integrated receiver for the measurement of electromagnetic field emissions. The autonomous receiver measures and registers the elevated emission levels of both components of the EM field originating from rocks subjected to increased mechanical stress. The receiver’s sensitivity of 60 µV/m, its dynamic range of 98 dB, and its impulse response of 0.23 V/µs were determined in laboratory conditions. Real EM field signals from hard coal samples subjected to crushing force were recorded using an autonomous receiver. The observed and recorded results confirm that the receiver operates in the full range of amplitudes of the EM field signal emitted from the rock. The results determine the band of characteristic signals for EM field emission from hard coal. The system created on the basis of autonomous EM receivers can support the existing seismic safety systems in real mine conditions by predicting the possibility of mine collapse hazards

    Dynamics of autonomous rock electromagnetic radiation measurement instrumentation

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    The paper analyzes the operation of innovative composite measurement instrumentation for spontaneous electromagnetic emission. The designed receiver measures and records both components of the EM field emitted by rocks subjected to increased mechanical stress. The range of signals transmitted by the receiver system and its dynamics were determined. A receiver was used to observe electromagnetic signals generated during a hard coal sample crushing in laboratory conditions. Test results confirmed the high dynamic range of the system at 98 dB and the ability to observe signals over a range of frequencies up to 50 kHz. The experimental results confirm the signal bandwidth characteristic of coal mine EM field emission obtained in earlier studies. The constructed autonomous receiver can be used in mine workings as a complementary warning system for emerging mine hazards

    Measurement of Electromagnetic Field Component Emissions as a Precursor of Emerging Hazard in Coal Mines

    No full text
    The article presents the results of research concerning electromagnetic (EM) field emitted by rocks during the process of their destruction. The paper describes a measuring stand designed for subjecting rock samples to axial crushing. During the destruction of rock samples, both components of the electromagnetic field emitted by the rock were recorded. The paper presents the results of research on hard coal samples, presenting the obtained time domain waveforms and frequency spectrum of the emitted EM field components. Further potential uses of tests concerned with EM emitted by rocks are determined. Applications registering EM field in mine environments may provide an early mine collapse warnings

    Activities of the radiointroscopy laboratory at the Electronics Department of the Wrocław University of Science and Technology

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    W artykule przedstawiono historię laboratorium radiointroskopii stworzonego przy Politechnice Wrocławskiej. Laboratorium w swojej ponad 50 letniej historii zajmowało się badaniami pól elektromagnetycznych emitowanych przez skały oraz grunt poddawanych mechanicznym naprężeniom. Laboratorium skupia się na budowie prototypowej aparatury badawczej i pomiarach polowych. Realizacja tematyki radiointroskopii zwieńczona jest wieloma publikacjami, 16 patentami, 4 doktoratami i 2 pracami habilitacyjnymi. Laboratorium kontynuuje swoje badania do dnia dzisiejszego, poszukując nowych dziedzin badawczych wykorzystania fal elektromagnetycznych w zastosowaniach nietelekomunikacyjnych.The paper presents the history of the radiointroscopy laboratory established at the Wroclaw University of Science and Technology. The laboratory in its over 50 years of history dealt with the study of electromagnetic fields emitted by rocks and soil subjected to mechanical stress. The laboratory focuses on building prototype research apparatus and field measurements. The implementation of the radiointroscopy subject matter is crowned with many publications, 16 patents, 4 doctorates and 2 habilitation theses. The laboratory continues its research to this day, seeking new research areas of application of electromagnetic waves in non-telecom applications
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