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Full-Text Articles in Mining Engineering
Dpm Dispersion Study Using Cfd For Underground Metal / Nonmetal Mines, Yi Zheng, Jerry C. Tien
Dpm Dispersion Study Using Cfd For Underground Metal / Nonmetal Mines, Yi Zheng, Jerry C. Tien
Mining Engineering Faculty Research & Creative Works
Diesel Particulate Matter (DPM) is considered carcinogenic after prolonged exposure. With increasing use of diesel-powered mining equipment in underground mines, miner's exposure to DPM has been increasing. Most studies on the issue has been DPM control measures with few studies on diesel exhaust propagation patterns after leaving the tailpipes. This study uses computational fluid dynamics (CFD) to investigate the airflow pattern in an underground metal/nonmetal mine for a single heading. Several high DPM concentration areas are identified in the study and common practices for compliance are suggested. Airflow and DPM distribution are compared between blowing and exhausting face ventilation systems. …
Ice Nucleation And Overseeding Of Ice In Volcanic Clouds, Adam J. Durant, R. A. Shaw, William I. Rose, Y. Mi, G. G. J. Ernst
Ice Nucleation And Overseeding Of Ice In Volcanic Clouds, Adam J. Durant, R. A. Shaw, William I. Rose, Y. Mi, G. G. J. Ernst
Department of Geological and Mining Engineering and Sciences Publications
Water is the dominant component of volcanic gas emissions, and water phase transformations, including the formation of ice, can be significant in the dynamics of volcanic clouds. The effectiveness of volcanic ash particles as ice-forming nuclei (IN) is poorly understood and the sparse data that exist for volcanic ash IN have been interpreted in the context of meteorological, rather than volcanic clouds. In this study, single-particle freezing experiments were carried out to investigate the effect of ash particle composition and surface area on water drop freezing temperature. Measured freezing temperatures show only weak correlations with ash IN composition and surface …
Further Results On Frequency-Domain Channel Equalization For Single Carrier Underwater Acoustic Communications, Y. Rosa Zheng, Chengshan Xiao, Xin Liu, Wen-Bin Yang, T. C. Yang
Further Results On Frequency-Domain Channel Equalization For Single Carrier Underwater Acoustic Communications, Y. Rosa Zheng, Chengshan Xiao, Xin Liu, Wen-Bin Yang, T. C. Yang
Electrical and Computer Engineering Faculty Research & Creative Works
A frequency-domain channel equalization and phase correction method was proposed in a previous work published in Oceans'07 conference, in which 10^-4 BER performance was presented for fixed-to-fixed source/receiver channels. The method is improved by using minimum mean square error (MMSE) estimation in channel updates rather than least squares estimation. It is applied to moving-to-fixed channels in the AUVFest'07 ocean experiment where single-carrier wideband transmission was employed with quadrature phase shift keying modulation. The moving source channels exhibit higher Doppler shift and larger Doppler drift than the fixed-to-fixed channels. Therefore, the number of symbols required for initial phase estimation is increased …
High Voltage Charging Of A Capacitor Bank, Sergey I. Shkuratov, Jason Baird, Evgueni F. Talantsev, A. V. Ponomarev, Larry L. Altgilbers
High Voltage Charging Of A Capacitor Bank, Sergey I. Shkuratov, Jason Baird, Evgueni F. Talantsev, A. V. Ponomarev, Larry L. Altgilbers
Mining Engineering Faculty Research & Creative Works
We have demonstrated the feasibility of charging a capacitor bank to a high voltage using an autonomous ultra-compact explosively driven source of prime power. The prime power source is a longitudinally driven shock wave depolarization of a ferroelectric ceramic. The energy-carrying elements of the shock wave ferroelectric generators (FEGs) were poled Pb(Zr52Ti48)O3 polycrystalline ceramic disks with 0.35 cm3 volume. FEGs charged 9 nF, 18 nF, and 36 nF capacitor banks and provided pulsed-power with peak amplitudes up to 0.29 MW. The maximum efficiency of electric charge transfer from shocked Pb(Zr52Ti48)O3 elements to a capacitor bank was 46%. We demonstrated experimentally …