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Articles 181 - 210 of 294
Full-Text Articles in Oil, Gas, and Energy
Common Midpoint Gather Constraint-Based Impedance Inversion Of Ground Penetrating Radar, Dai Qianwei, Ning Xiaobin, Zhang Bin
Common Midpoint Gather Constraint-Based Impedance Inversion Of Ground Penetrating Radar, Dai Qianwei, Ning Xiaobin, Zhang Bin
Coal Geology & Exploration
GPR impedance inversion is an effective method to obtain accurately the intrinsic parameters of the subsurface medium. This method relies on low frequency information provided by logging data, but it is rarely accompanied by drilling in practical applications. To solve the problem, the common midpoint velocity analysis is employed to provide more low frequency component information for impedance inversion of GPR to finely reconstruct the dielectric parameter of subsurface in the framework of velocity-constrained inversion technique. Firstly, a layer model is specifically set up as an example to verify the feasibility of the developed velocity- constrained inversion to regulate the …
Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff
Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff
Faculty Publications
Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …
Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake
Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake
LSU Master's Theses
Techno-economic analyses play an important role in determining locations for conventional wind turbine installations. This method is utilized to assess energy production potential for a new type of wind technology, known as airborne wind energy (AWE). The first objective of the present thesis was to determine overall investment potential of a utility-scale floating offshore airborne wind farm, testing five floating platform design concepts. The second objective was to determine whether the wind resources (100-1500 m) are ideal to support AWE systems in the Gulf of Mexico. Specifically, a hypothetical benchmark wind farm was developed 15 km offshore from Venice, Louisiana. …
Developing And Implementing A 100% Renewable Electricity Resolution: A Research-Based Framework, Emily E. Skill, Roslynn Brain Mccann, Sarah C. Klain
Developing And Implementing A 100% Renewable Electricity Resolution: A Research-Based Framework, Emily E. Skill, Roslynn Brain Mccann, Sarah C. Klain
All Current Publications
While it may seem that the efforts of local governments have only a marginal impact on the global issue of climate change, local action can spread to generate large-scale change. Local action can inspire other communities to adopt policies, creating the potential to expand and form regional action on climate change. Furthermore, local policies can influence state and federal policies. This guide will walk you through a five-step framework that was developed from the results of a qualitative research study that explored how three Utah cities, Salt Lake City, Park City, and Moab, successfully adopted 100% renewable electricity resolutions.
Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson
Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson
Electronic Theses and Dissertations
Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.
This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central …
A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila
A Geochemical Perspective On The Hydrocarbon Compositional Variation Within East Malay Basin: Implication For Oil Exploration, Mohd Sharef Nurfadhila
Student Works (2020-2029)
Malay Basin is a prospective basin which perceived to be matured basin in terms of hydrocarbon generating potential. Many significant oil discoveries made since 1970’s includes Seligi, Pulai, Tapis and Bekok oil fields. These fields have been producing until now. Despite its matured stage, there are still more oil discoveries in various parts of Malay Basin until now. Oil discoveries include light and high density oils with various challenges in oil development project. This dissertation focuses on oil fields in East Malay Basin particularly Lerek, Chermingat, Lawang and Serudon oil fields. The objectives of this research are to study the …
Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh
Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh
Civil and Environmental Engineering and Construction Faculty Research
Considering environmental concerns regarding air pollution which is induced by burning fossil fuels to generate electrical power, utilizing solar energy as a green and sustainable energy source is of great interest. This study proposes a novel framework to determine the optimal location for constructing solar photovoltaic (PV) farms. To locate the suitable areas for PV farms, firstly, a fuzzy-based method is utilized to homogenize the input parameters, thereafter, the analytical hierarchy process (AHP) and Dempster-Shafer (DS) methods are independently used. In the AHP method, the proper weight for each input parameter is generated utilizing a pairwise comparison matrix. However, the …
Clean Alternatives For Household Coal - Case Study: Izmir, Turkey, Yagiz Yar
Clean Alternatives For Household Coal - Case Study: Izmir, Turkey, Yagiz Yar
Master's Projects and Capstones
Household coal consumption during the heating season affects Izmir’s air quality adversely to the point where air quality indicators show that pollution levels exceed limit concentration values that World Health Organization set for a habitable and healthy ambient air. The objective of this paper is to evaluate alternatives that utilize low-carbon emitting methods of domestic heating fueled by renewable energy sources and develop a model which would replace household coal. Research shows that 223,969 tonnes of coal were burned in households of Izmir in 2019 and analysis results show that 2.72 million MMBtu of heat energy was supplied to these …
A Review Of Methods To Better Predict And Reduce The Risk Of Hurricane Damage To The Energy Sector, Zackary Litalien
A Review Of Methods To Better Predict And Reduce The Risk Of Hurricane Damage To The Energy Sector, Zackary Litalien
Master's Projects and Capstones
In the event of a hurricane, electricity is the most important utility as it provides heat, water, food, light, communication, and medical care to communities. Research predicts an increase in frequency and strength of hurricanes with time due to climate change, which requires communities and electric utility companies to be prepared for the inevitable. This paper assesses existing methods of hurricane preparation and restoration of the electric power grid in hurricane prone locations with regards to the electric utility companies and electric distribution systems. In this study, I perform a comparative analysis between different methods of planning and forecasting electrical …
Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre
Assessing The Potential For Greater Solar Development In West Texas, Usa, Dale D. Devitt, M. H. Young, J. P. Pierre
Life Sciences Faculty Research
As population and economies continue to grow on a global scale, so too does the demand for energy. To improve reliability and independence of energy supplies, the U.S. and many other countries are seeking internally-sourced renewable energy; solar is one such renewable-energy source that meets these criteria. However, all energy sources exert some environmental impacts. In the case of solar, direct impacts stem mostly from alteration of land needed to host infrastructure. Understanding the environmental upside and downside potential of solar energy systems allows a more comprehensive, side-by-side comparison with different energy sources. In this article, we focus on the …
An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald
An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald
Honors Scholar Theses
The purpose of this project is to design a clean energy-sourced microgrid for UConn’s main campus that would reduce the university’s energy emissions while remaining within the geographic boundaries of viable UConn-owned land. Economic cost was not considered in this analysis; instead, emissions and space constraints were the optimized measures of value and feasibility. Sources of energy that were considered include photovoltaics (PV), wind turbines, hydrokinetic systems, and fuel cells. Energy storage capacity was included in the analysis as well. The overall system was optimized first by ignoring space constraints and for a minimum of 10% reduction from the current …
Efficiency Analysis Of Harvesting Solar Energy To Perform Mechanical Work, Haden S. Bragg
Efficiency Analysis Of Harvesting Solar Energy To Perform Mechanical Work, Haden S. Bragg
Undergraduate Theses and Capstone Projects
The majority of the world’s electricity is generated using fossil fuels; in fact, the United States Energy Information Administration (EIA) states that the U.S. used fossil fuels to generate 62.7 % of its electricity in 2019 [1]. The goal of this research was to create a system that could perform mechanical work using only renewable resources. We built a solar charging station that uses two solar panels to generate electricity and an electric bicycle whose battery can be charged using the charging station. The efficiency for the type of solar cell used in this project is well established. Therefore, in …
Key Technology For Rapidly Drilling Large Diameter Destressing-Drillhole In Rockburst Coal Seam, Wei Hongchao, Wang Yi, Wang Bo
Key Technology For Rapidly Drilling Large Diameter Destressing-Drillhole In Rockburst Coal Seam, Wei Hongchao, Wang Yi, Wang Bo
Coal Geology & Exploration
In order to improve the hole forming rate and construction efficiency of large diameter destressing-drillhole in rockburst mine, based on the analysis of the stress characteristics of coal rock in rockburst coal mine, the dynamic instability characteristics of destressing-drillhole and the construction features, the key points for drilling large diameter destressing-drillhole, the efficient discharge of cuttings and fast drilling/lifting were proposed. Combining with the discharge of cuttings method by dual-power, the technology and equipment for rapidly drilling large diameter destressing-drillhole in rockburst coal seam were formed finally after the design and optimization of key equipment, drilling tools, technology and drilling …
Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei
Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei
Coal Geology & Exploration
Aiming at the limitation of middle pressure air drilling for gas drainage in soft and broken coal seam, such as limited drill cutting removal capacity, and dust pollution, foam drilling technique research in underground coal mines was carried out. CFD simulation of the flow field during the drilling process was conducted to obtain the optimized drilling tool structure parameters for efficient drill cutting transportation. Optimal structural parameters of wide-blade milled auger drill rod with the number of heads 3, the groove width 26 mm, and the pitch 110 mm were determined. A foam perfusion system suitable for underground coal mining …
Distribution And Resource Prospect Of Metal Ore Spots(Deposits) In Coal Of Different Coal-Forming Ages In Northern China, Ning Shuzheng, Huang Shaoqing, Zhang Li, Huang Wenhui, Cao Daiyong, Yuan Jianjiang, Zhang Jianqiang, Zhu Shifei, Yan Deyu, Liu Kang
Distribution And Resource Prospect Of Metal Ore Spots(Deposits) In Coal Of Different Coal-Forming Ages In Northern China, Ning Shuzheng, Huang Shaoqing, Zhang Li, Huang Wenhui, Cao Daiyong, Yuan Jianjiang, Zhang Jianqiang, Zhu Shifei, Yan Deyu, Liu Kang
Coal Geology & Exploration
In some cases, metals such as germanium, gallium, lithium and rare earth elements can be enriched in coal, which is an important potential source of these metals. There are abundant coal resources in northern China, and a large number of coal-metal ore spots(deposits) have been found, and the distribution of these ore spots(deposits) shows certain temporal and spatial characteristics: Metals in Permo-Carboniferous coal occur mainly as gallium and lithium-enriched ore spots, mainly are distributed in the northern coalfields of North China coal bearing regions and mining areas such as Pingshuo and Jincheng in Shanxi Province; the metal enrichment in Early-Middle …
Causes Of Anomaly Of Rare Earth Elements Of Seam 2 Of Yan’An Formation In The Northern Margin Of Ordos Basin And Its Geological Significance, Yang Yi, Lyu Dawei, Zhang Jianqiang, Wu Dun
Causes Of Anomaly Of Rare Earth Elements Of Seam 2 Of Yan’An Formation In The Northern Margin Of Ordos Basin And Its Geological Significance, Yang Yi, Lyu Dawei, Zhang Jianqiang, Wu Dun
Coal Geology & Exploration
The cause of rare earth elements(REE) anomalies in No.2 coal seam of the Yan’an Formation in the northern margin of the Ordos basin has been controversial. This paper takes Dahaize coal mine, Yulin area with well developed No.2 coal as an example to analyze REE, mineralogical characteristics of coal and partings, and to reveal the causes of anomaly of REE by Inductive Coupled Plasma Mass Spectrometry(ICP-MS) and Scanning Electron Microscopy(SEM). The results show that the total rare earth element(∑REE) concentration in the coal samples ranges from 3.71 to 46.21 μg/g. Light rare earths elements(LREE, La-Eu) are more abundant than heavy …
Influencing Factors Of The Dynamic Permeability Of Cbm Reservoir And Cbm Well Drainage Control Measures, Wang Qing, Yang Fei, Gong Weicheng, Xu Tianxin, Li Yichao
Influencing Factors Of The Dynamic Permeability Of Cbm Reservoir And Cbm Well Drainage Control Measures, Wang Qing, Yang Fei, Gong Weicheng, Xu Tianxin, Li Yichao
Coal Geology & Exploration
The drainage and production control method has significant impact on the permeability of coalbed methane reservoir. Based on the main control factors of the permeability at different stages of drainage and production of coalbed methane wells, this paper puts forward targeted drainage and production countermeasures with the goal of improving the permeability. When the bottom-hole flow pressure was greater than the original reservoir pressure, the step-down velocity was between 0.08 and 0.1 MPa/d to reduce fracturing fluid and velocity-sensitive damage. When the bottom hole flow pressure was between reservoir pressure and desorption pressure, the pressure could be reduced at a …
Dynamic Evolution Law Of Water Accumulation Range In Coal Mining Subsidence Area With High-Level Groundwater, Chen Xiaoxie, Zhang Wentao, Zhu Xiaojun, Liu Hui, Zhang Min, Sun Aiguo, Yang Xiaoyu
Dynamic Evolution Law Of Water Accumulation Range In Coal Mining Subsidence Area With High-Level Groundwater, Chen Xiaoxie, Zhang Wentao, Zhu Xiaojun, Liu Hui, Zhang Min, Sun Aiguo, Yang Xiaoyu
Coal Geology & Exploration
In order to study the dynamic evolution law of the water accumulation range with high-level groundwater, the working face 1031 of Wugou coal mine was taken as the research area. Based on Landsat-8 remote sensing data, the evolution law of water accumulation range above working face 1031 during 2013-2017 was summarized and the influence of factors such as net rainfall, groundwater depth and working surface propulsion distance on the evolution of water accumulation range was analyzed. The concept of the boundary angle of the water accumulation range was proposed, and the functional relationship between the angle and the mining time …
Preparation Of Underwater Quick-Set And Expansion Polyurethane Grouting Material And Its Properties, Yang Zhu, Xue Ren, Wang Jun, Lan Zhili
Preparation Of Underwater Quick-Set And Expansion Polyurethane Grouting Material And Its Properties, Yang Zhu, Xue Ren, Wang Jun, Lan Zhili
Coal Geology & Exploration
Quick plugging and dynamic grouting technology under complex geologic conditions in mines is a technical problem in the field of grouting and one of the effective solutions is to develop new chemical grouting materials. Based on the reaction principle of polyurethane materials, we carried out the research and development on production formula of polyurethane grouting materials. By analyzing the polyurethane synthesis reaction temperature and the way of adding reagents as well as conducting contrast experiments on various auxiliaries and additives the best formula for the material was determined. It was found that the grouting material prepared by 4% nano silica …
Classification Of Hidden Faults In Coal Seam Floor And Measures For Water Inrush Prevention, Liu Zewei, Liu Qisheng, Liu Yang
Classification Of Hidden Faults In Coal Seam Floor And Measures For Water Inrush Prevention, Liu Zewei, Liu Qisheng, Liu Yang
Coal Geology & Exploration
The floor hidden faults with mine water bursting coefficient between 0.06 and 0.1 MPa/m have not been classified scientifically in combination with mining. Based on the characteristics of hidden faults in coal seam floor and the vertical relationship between the location of the top interface of the hidden fault and the " Three Underlying Belts", the hidden faults in coal seam floor are classified into three types: high, middle, and low from the perspective of mine water prevention of the floor. Through theoretical analysis and case analysis of water inrush, it is pointed out that the high hidden fault with …
Application Of Mjs Construction Method In Gravel Layer And Pile Forming Difference, Zhang Yan, Tian Zenglin, Cao Haidong, Dang Yakun, Wang Hai, Li Heping, Han Qiang
Application Of Mjs Construction Method In Gravel Layer And Pile Forming Difference, Zhang Yan, Tian Zenglin, Cao Haidong, Dang Yakun, Wang Hai, Li Heping, Han Qiang
Coal Geology & Exploration
During the construction of water cutoff curtain in an open-pit coal mine in China, parts of the grouting groove couldnot be constructed due to many obstacles such as overhead high-voltage wire, buried optical cable and buried drainage pipe, and MJS construction method was chosen instead to build the cutoff curtain. The results of MJS pile tests show that the quality of piles formed by this method was obviously different in the construction area of gravel layer on the east and west sides. By the methods of geological exploration, gravity penetration test and pumping test, this paper makes a comparative analysis …
Mineralogical Characteristics And Genesis Of The Illite In Jurassic Coal Of The Jingxi Coalfield, North China, Huang Bo, Zheng Qiming, Shi Songlin
Mineralogical Characteristics And Genesis Of The Illite In Jurassic Coal Of The Jingxi Coalfield, North China, Huang Bo, Zheng Qiming, Shi Songlin
Coal Geology & Exploration
In order to study the indicating effect of illite for coalification and sedimentary environments, the Jurassic coal seam gangue in Jingxi coalfield of North China was taken as the research object. X-ray diffraction(XRD) and X-ray fluorescence(XRF) were used to determine the mineral composition and chemical composition of the gangue sandwiched in the coal seam gangue. The mineralogical characteristics and genesis of illite in the gangue were studied. The results indicated that the intra-seam partings are mainly composed of illite, chlorite and quartz, followed by small amount of calcite and albite. The illite has an average proportion of 62.92%. According to …
Changes Of Petrographic Characteristics And Quality Of Contact-Metamorphosed Coals In The Datong Coalfield, Ma Hongtao, Song Xiaoxia, Li Kaijie, Zhao Jingui, Zhang Tianguang, Liu Jianping
Changes Of Petrographic Characteristics And Quality Of Contact-Metamorphosed Coals In The Datong Coalfield, Ma Hongtao, Song Xiaoxia, Li Kaijie, Zhao Jingui, Zhang Tianguang, Liu Jianping
Coal Geology & Exploration
Igneous intrusions in the Datong coalfield caused a considerable amount of contact metamorphosed coal, reducing the industrial value of coal. The effect of a dike in roadway 5222 in Tashan coal mine was determined from analysis of 16 samples collected near the intrusive body. Microscopic and macroscopic observation, proximate and ultimate analysis were used to determine the petrographic characteristics. The results demonstrate that contact-metamorphosed coal experienced significant thermal alteration during intrusive event. Microscopically, various natural coke microstructures, such as mosaic structure, flow structure and pyrolytic carbon were formed under excess heat; instant heating for coals resulted in the elevation of …
Creep Acoustic Emission And Fractal Characteristics Of Coal Rock Under High Temperature Pre-Damage, Shi Hongcai
Creep Acoustic Emission And Fractal Characteristics Of Coal Rock Under High Temperature Pre-Damage, Shi Hongcai
Coal Geology & Exploration
The thermal damage and triaxial creep acoustic emission experiments of coal samples at different temperatures were carried out to investigate and analyze the mechanical characteristics of coal and rock after high temperature pre-damage. The results show that the thermal damage of coal and rock increases exponentially with the increase of temperature; the brittle-ductile failure characteristics of coal and rock appear at lower temperature(≤200℃) and the accelerated creep characteristics are not obvious; the brittle-brittle failure characteristics of coal and rock appear at higher temperature(>200℃) and the accelerated creep characteristics are more obvious; the value of steady creep rate is between pre-damage …
Directional Drilling Technology And Equipment Of Pneumatic Screw Motor In Soft Seam, Zhang Jie, Wang Yi, Huang Hanjing
Directional Drilling Technology And Equipment Of Pneumatic Screw Motor In Soft Seam, Zhang Jie, Wang Yi, Huang Hanjing
Coal Geology & Exploration
Aiming at the drilling problems of shallow depth, uncontrollable trajectory and blind area of extraction in soft coal seam, the directional drilling technology of pneumatic screw motor was invented, and the directional drilling equipment consisting of pneumatic screw motor, narrow structure directional drilling rig and MWD system were formed. The air directional drilling technology and hole-completion technology were studied and developed. The technology of drilling and hole-completion solves the problem of long-distance safe drilling and hole protection of directional drilling along soft coal seam. The technology has been successfully tested in a coal mine, Huainan, with 30 test boreholes with …
Numerical Simulation Of Propagation Law Of Pore-Fracture Under Uniaxial Stress, Guo Xiucheng
Numerical Simulation Of Propagation Law Of Pore-Fracture Under Uniaxial Stress, Guo Xiucheng
Coal Geology & Exploration
in order to study the law of crack propagation under different pore-fracture conditions, the crack propagation process, acoustic emission law and stress-strain curve under different crack inclination angle and different heterogeneous coefficient were numerically simulated by using RFPA software. At the same time, the results are compared with the experimental results. The results show that the cracks of the intact specimen are produced along the shear direction, while the cracks of the specimens with pores occur along the side of the crack tip and the orifice. The secondary cracks in horizontal direction and bifurcation at the prefabricated crack tip or …
Joint Correction Method Of Errors Of Mwd Inclinometer In Underground Coal Mine, Qiao Meiying, Wang Bo, Xiao Xuejun, Xu Chengkuan, Yan Shuhao
Joint Correction Method Of Errors Of Mwd Inclinometer In Underground Coal Mine, Qiao Meiying, Wang Bo, Xiao Xuejun, Xu Chengkuan, Yan Shuhao
Coal Geology & Exploration
In order to reduce the error of measuring the drilling attitude angle parameter of MWD inclinometer in coal mine, a mathematical model of error compensation based on recursive least squares was established, the joint correction method of ellipsoid fitting method, dot product invariance method and rotation plane fitting method were used in the error compensation correction for MWD inclinometer. Numerical simulation experiment and double-axis turntable experiment were carried out on the developed MWD inclinometer, error compensation correction of experimental data was conducted with joint correction method, the maximum absolute errors of pitch angle and azimuth angle before correction are 4.7° …
Table Of Contents, The Editors
The Potential Of Clean Utilization Of Coal Resources In Main Coalfields Of Henan Province, Zhao Mingzhen
The Potential Of Clean Utilization Of Coal Resources In Main Coalfields Of Henan Province, Zhao Mingzhen
Coal Geology & Exploration
In order to systematically analyze the distribution characteristics of the main harmful elements in coal in different coalfields of Henan Province and assess the potential of clean utilization of coal resources, through systematic collection of coal quality data of 12 coalfields and uniform sampling for test, the average content of 11 harmful elements in each coalfield was obtained. The weighted scale index method of generalized contrast was used to calculate the comprehensive index I of the clean potential of coal resources and assess the clean utilization potential of coal resources. The conclusion that the clean quality of coal resources in …
Application Of Simulink In Transient Process Analysis Of Transient Electromagnetic Field, Liu Shilei, Zhang Ying, Yue Jianhua
Application Of Simulink In Transient Process Analysis Of Transient Electromagnetic Field, Liu Shilei, Zhang Ying, Yue Jianhua
Coal Geology & Exploration
In order to analyze the distribution and variation law of transient electromagnetic field intuitively, the response equations of transient electromagnetic field under different damping states are theoretically derived, including a modeled transient process of transient electromagnetic field via Simulink. The equivalent circuit modules of excitation current, transmitting loop, geological anomaly body, receiving coil and their mutual inductance modules are developed. The influence of inductance, distributed capacitance and resistance on the equivalent circuit of transmitting and receiving loops are systematically studied. The results indicate a direct determination of the excitation waveform characteristics of the transient electromagnetic field based on the damping …