Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Earth Sciences (16248)
- Geology (13576)
- Life Sciences (3500)
- Computer Sciences (3464)
- Environmental Sciences (2811)
-
- Engineering (2086)
- Chemistry (1794)
- Soil Science (1672)
- Plant Sciences (1632)
- Social and Behavioral Sciences (1459)
- Physics (1366)
- Mathematics (1340)
- Sustainability (1010)
- Artificial Intelligence and Robotics (827)
- Medicine and Health Sciences (812)
- Computer Engineering (780)
- Ecology and Evolutionary Biology (763)
- Oceanography and Atmospheric Sciences and Meteorology (696)
- Statistics and Probability (661)
- Environmental Education (519)
- Natural Resources and Conservation (493)
- Electrical and Computer Engineering (478)
- Urban Studies and Planning (470)
- Education (466)
- Environmental Monitoring (451)
- Numerical Analysis and Scientific Computing (442)
- Databases and Information Systems (438)
- Astrophysics and Astronomy (428)
- Natural Resources Management and Policy (416)
- Institution
-
- Western Michigan University (13205)
- University of Kentucky (1719)
- TÜBİTAK (651)
- University of Nebraska - Lincoln (649)
- Singapore Management University (573)
-
- Loyola Marymount University and Loyola Law School (445)
- Old Dominion University (373)
- China Simulation Federation (315)
- University of Texas Rio Grande Valley (251)
- City University of New York (CUNY) (219)
- Chulalongkorn University (215)
- University of South Carolina (213)
- China Coal Technology and Engineering Group (CCTEG) (204)
- Montana Tech Library (195)
- Western University (194)
- University of Texas at El Paso (187)
- Utah State University (183)
- Kennesaw State University (181)
- Missouri University of Science and Technology (181)
- University of South Florida (174)
- Louisiana State University (171)
- Portland State University (170)
- William & Mary (162)
- University of Arkansas, Fayetteville (153)
- Air Force Institute of Technology (149)
- Boise State University (143)
- Technological University Dublin (130)
- University of Nevada, Las Vegas (128)
- Claremont Colleges (111)
- The University of Maine (110)
- Keyword
-
- Machine learning (190)
- Deep learning (163)
- Climate change (135)
- COVID-19 (125)
- Machine Learning (120)
-
- Technical Reports (109)
- UTEP Computer Science Department (109)
- Deep Learning (76)
- Alfalfa (73)
- Sustainability (70)
- Priority Soils (65)
- Mathematics (61)
- Artificial intelligence (59)
- Computer Science (59)
- Chemistry (58)
- Simulation (54)
- Remote sensing (52)
- Water Quality (52)
- Cybersecurity (47)
- Lake (46)
- Nitrogen (46)
- Lakes Lay Monitoring Program (45)
- Optimization (43)
- Climate (42)
- Artificial Intelligence (41)
- Environment (41)
- Blockchain (40)
- Soil Sampling (40)
- Classification (39)
- Computer vision (39)
- Publication
-
- Legacy Scout Tickets from Pure Oil Company (11044)
- Thin Sections (2130)
- IGC Proceedings (1993-2023) (1502)
- Theses and Dissertations (537)
- Research Collection School Of Computing and Information Systems (513)
-
- Journal of System Simulation (315)
- Faculty Publications (283)
- Electronic Theses and Dissertations (262)
- Chulalongkorn University Theses and Dissertations (Chula ETD) (215)
- Coal Geology & Exploration (204)
- Turkish Journal of Electrical Engineering and Computer Sciences (202)
- Silver Bow Creek/Butte Area Superfund Site (194)
- Turkish Journal of Mathematics (186)
- Turkish Journal of Chemistry (167)
- United States Department of Agriculture Wildlife Services: Staff Publications (136)
- Honors Theses (122)
- Dissertations (115)
- USF Tampa Graduate Theses and Dissertations (112)
- Departmental Technical Reports (CS) (109)
- Graduate Theses and Dissertations (108)
- School of Natural Resources: Faculty Publications (106)
- Publications and Research (99)
- Doctoral Dissertations (96)
- Research outputs 2014 to 2021 (93)
- C-Day Computing Showcase (87)
- Electronic Thesis and Dissertation Repository (86)
- All Works (83)
- Articles (82)
- Physics Faculty Publications (81)
- Module 10: Garden Ecology (78)
- Publication Type
Articles 2131 - 2160 of 27884
Full-Text Articles in Physical Sciences and Mathematics
Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li
Distribution Characteristics And Paleo-Climatic Significance Of Continental Climate-Sensitive Sediments In The Late Cretaceous In China, Bin Xu, Fang Xiang, Shuxia Li
Coal Geology & Exploration
The Cretaceous is a typical period for studying the greenhouse climate and the earth system interactions, and the world's most extensive terrestrial strata are mainly in East Asia, especially in China. Continental sediments can effectively reflect the paleo-climate change, but the previous studies of the Late Cretaceous paleo-climate, based on the combined characteristics of continental climate-sensitive sediments, were barely found in China. To obtain the Late Cretaceous paleo-climate characteristics of China, the distribution characteristics of different continental climate-sensitive sediment types in the early, middle and Late Cretaceous in China were studied in detail. According to the distribution and combination characteristics …
Application And Development Of Advanced Drilling Technology For Coal Mine Roadway Heading, Zhang Youzhen, Fan Tao, Kan Zhitao, Wei Hongchao, Chen Hongyan
Application And Development Of Advanced Drilling Technology For Coal Mine Roadway Heading, Zhang Youzhen, Fan Tao, Kan Zhitao, Wei Hongchao, Chen Hongyan
Coal Geology & Exploration
With the development of intelligent and fast roadway heading in coal mines, the demand for advanced and fine exploration of heading face is becoming increasingly urgent. Considering the technical characteristics of roadway heading and tunnel drilling, this paper firstly analyzes the technical characteristics and technical requirements of roadway heading advanced drilling under the background of intelligent green mining of coal mines and describes the innovative practice of technology and equipment, such as the integration of excavation and exploration, dual-arm advanced drilling and comprehensive exploration based on directional drilling to effectively solve the contradiction of exploration and excavation and improve the …
Classifying Soft X-Ray Objects In The Galactic Bulge, Joshua D. Wetuski
Classifying Soft X-Ray Objects In The Galactic Bulge, Joshua D. Wetuski
LSU Doctoral Dissertations
The Galactic Bulge Survey (GBS) is a broad and shallow X-ray survey designed to detect quiescent X-ray binary systems in the direction of the Milky Way bulge, which include objects such as low-mass X-ray binaries, cataclysmic variables, and symbiotic binaries. LMXBs can provide constraints to the neutron star equation of state and symbiotic systems and are likely progenitors of double white dwarf systems which are themselves candidate progenitors to type Ia supernova. We seek to improve identification and classification of optical counterparts to GBS in several ways. By improving upon the original GBS, an updated catalog was created to help …
Automated Identification Of Stages In Gonotrophic Cycle Of Mosquitoes Using Computer Vision Techniques, Sherzod Kariev
Automated Identification Of Stages In Gonotrophic Cycle Of Mosquitoes Using Computer Vision Techniques, Sherzod Kariev
USF Tampa Graduate Theses and Dissertations
In this paper, we design Computer Vision techniques to determine stages in the Gonotrophic cycle of mosquitoes. The dataset for our problem came from 125 adult female mosquitoes - each of which belonged to one of three species - Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. The mosquitoes were raised in a lab and passed through all fourGonotrophic stages (Un-fed, Fully-fed, Semi-gravid, and Gravid). At each stage, their images were captured on a plain background via a Xiaomi smartphone, resulting in a dataset of 1784 images. The images were then augmented using standard techniques to generate a larger dataset of …
Table Of Contents, The Editors
Adsorption Phase Density Characteristics Of Supercritical Methane Of Granular Coal, Zhang Mingjie, Liu Hao, Jia Tianrang, Gong Ze, Yang Mingxin
Adsorption Phase Density Characteristics Of Supercritical Methane Of Granular Coal, Zhang Mingjie, Liu Hao, Jia Tianrang, Gong Ze, Yang Mingxin
Coal Geology & Exploration
Finding out the characteristics of supercritical methane adsorption phase density of granular coal is the basis of studying the influence of temperature and pressure on methane adsorption amount of coal sample. Granular coal samples collected from Hebi No.6 Mine and Longshan Mine in Anyang-Hebi Coalfield were used to measure the isothermal adsorption lines at temperatures of 308 K, 313 K and 318 K, and pressures of 1-24 MPa by magnetic suspension balance isotherm adsorption device. The intercept method, Langmuir ternary model fitting method and liquid phase density method were used to calculate the adsorbed phase density at adsorption saturation and …
De-Blocking Technology And Application Of High-Rank Cbm Well In Junlian Region In Sichuan Province, Peng Lisha, Zhang Yimin, Xiong Wei, Zhao Dan, Luo Kai
De-Blocking Technology And Application Of High-Rank Cbm Well In Junlian Region In Sichuan Province, Peng Lisha, Zhang Yimin, Xiong Wei, Zhao Dan, Luo Kai
Coal Geology & Exploration
The coal seams of Leping Formation in Junlian area are high-rank coal reservoir with low porosity and low permeability. The gas production of some coalbed methane wells decreases rapidly in the production process, which seriously restricts the benefit development of coalbed methane wells. Combined with the production data such as drainage, hydrochemistry and pump inspection, this paper analyzes the reasons for the decline of gas production. The main reasons for the decline are coal scaling and coal fines blockage. Targeted measures such as acid pickling, hydraulic shock, plasma pulse and water injection are carried out to remove the blockage. The …
Remediation Techniques For Cadmium-Contaminated Dredged River Sediments After Land Disposal, Zhang Changsong
Remediation Techniques For Cadmium-Contaminated Dredged River Sediments After Land Disposal, Zhang Changsong
Coal Geology & Exploration
The remediation of heavy metal Cd contamination in municipal waste is one of the urgent environmental problems in China. To determine the best Cd pollution remediation technology, this paper investigates the applicability of various cadmium(Cd) remediation techniques in river treatment. These remediation methods are compared and analyzed based on the dredged river sediments after land disposal in a city in East China. Three remediation techniques of stabilization, soil leaching, and phytoremediation, are compared by analyzing the performance of the techniques for Cd-contaminated soil remediation. The experimental results show that the stabilization technique reduced the leaching rate of soil Cd from …
Improvement And Test Of Radar Imaging Logging Tool For Oil And Gas Wells, Zhao Yonggang
Improvement And Test Of Radar Imaging Logging Tool For Oil And Gas Wells, Zhao Yonggang
Coal Geology & Exploration
The detection depth of traditional logging tools is basically less than 3 m, and without azimuth resolution, the formation structure in larger area around wells cannot be imaged. Therefore the problems arising in the detection of subtle structure and oil and gas reservoirs can not be solved. In response to such problems, radar imaging logging tool is developed by applying ground penetrating radar imaging technology to logging. In order to improve the detection depth, azimuth resolution and downhole depth of the tool, a nanosecond pulse source and directional receiving antennae are used to detect and image the formation around the …
Friction Law Of Compound Drilling Along The Coal Seam With Super-Long Directional Drilling, Xu Chao, Jiang Lei, Wang Xian, Fang Jun, Chen Pan, Liu Zhi
Friction Law Of Compound Drilling Along The Coal Seam With Super-Long Directional Drilling, Xu Chao, Jiang Lei, Wang Xian, Fang Jun, Chen Pan, Liu Zhi
Coal Geology & Exploration
The internal friction is the main factor affecting the drilling rate and drilling efficiency in super-long directional drilling in coal mines. In order to meet the objective demand of gas drainage mode in big panels, the friction and its influence law in drilling process are studied. To provide a basis for the selection of friction reduction process parameters of compound drilling along coal seam with super-long directional drilling, the drill string motion characteristics and stress state under the condition of near-horizontal compound drilling in the coal mine are analyzed. With certain conditional assumptions, the mechanical models of axial frictional resistance …
Development Characteristics And Controlling Factors Of Coal-Measure Source Rocks In The Global Tethys Region, Qu Tong, Huang Zhilong, Wang Rui, Tan Sizhe, Li Zhiyuan, Guo Xiaobo, Zhao Jing, Pan Yongshuai
Development Characteristics And Controlling Factors Of Coal-Measure Source Rocks In The Global Tethys Region, Qu Tong, Huang Zhilong, Wang Rui, Tan Sizhe, Li Zhiyuan, Guo Xiaobo, Zhao Jing, Pan Yongshuai
Coal Geology & Exploration
Under the control of tectonic activity in the Tethys region, a series of basins with coal measure source rocks developed, and the Tertiary coal in the circum Pacific belt is characterized by "hydrogen-rich" and has great hydrocarbon generation potential.This type of coal measure strata is an important source rock in petroliferous basins along the southeast coast of China.Therefore, it is particularly important to systematically analyze the development characteristics and controlling factors of coal measure source rocks under the Tethys background. Based on the systematic analysis of the development age, environments, geochemical characteristics and biomarker characteristics of the coal measure source …
Influence Of Surrounding Rock Changes On The Coal Seam Reflected Wave Under Thin Interbed Condition, Chang Suoliang, Zhang Sheng, Liu Jing, Liu Zuiliang, Chen Qiang, Liu Bo
Influence Of Surrounding Rock Changes On The Coal Seam Reflected Wave Under Thin Interbed Condition, Chang Suoliang, Zhang Sheng, Liu Jing, Liu Zuiliang, Chen Qiang, Liu Bo
Coal Geology & Exploration
In order to study the influence of the changes of surrounding rock on the reflected wave of coal seam under the condition of thin interbeds, the coal-bearing strata in the λ/4 thin layer range in seismic exploration is taken as the research object, and three types of models of surrounding rock lithology, thickness and structure change are established. By Brekhovskikh equation in the theory of thin-bed reflection coefficient spectrum, the influence of surrounding rock changes on the AVO curve, attributes and gathers of coal seams are calculated and summarized. The research results show that the changes of surrounding rock …
Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam
Assessing Morphological Response And Vulnerability Of Barrier Islands To Extreme Storms In Northwest Florida, Jacob Adam
USF Tampa Graduate Theses and Dissertations
Barrier islands shield the mainland coast from the effects of extreme storms such as increased wave energy and storm surge. During these events, however, barrier morphology can be altered by erosive forces. Thus, compromising the protection offered and leading to increased impact on the mainland. The St. Joseph Peninsula, located in the Northwest of the Gulf of Mexico, is one such barrier at threat from storm-induced erosion. Presented here is an assessment of morphology change induced by two major storms to impact the peninsula, Hurricanes Dennis 2005 and Michael 2018. These changes characterize the erosive/depositional patterns that can be expected …
Tracking Secondary Lahar Flow Paths And Characterizing Pulses And Surges Using Infrasound Array Networks At Volcán De Fuego, Guatemala, Ashley R. Bosa, Jeffrey B. Johnson, Silvio De Angelis, John J. Lyons, Amilcar Roca, Jacob F. Anderson, Amando Pineda
Tracking Secondary Lahar Flow Paths And Characterizing Pulses And Surges Using Infrasound Array Networks At Volcán De Fuego, Guatemala, Ashley R. Bosa, Jeffrey B. Johnson, Silvio De Angelis, John J. Lyons, Amilcar Roca, Jacob F. Anderson, Amando Pineda
Geosciences Faculty Publications and Presentations
Lahars are one of the greatest hazards at many volcanoes, including Volcán de Fuego (Guatemala). On 1 December 2018 at 8:00 pm local Guatemala time (~2:06:00 UTC), an hour-long lahar event was detected at Volcán de Fuego by two permanent seismo-acoustic stations along the Las Lajas drainage on the southeast side. To establish the timing, duration, and speed of the lahar, infrasound array records were examined to identify both the source direction(s) and the correlated energy fluctuations at the two stations. Co-located seismic and acoustic signals were also examined, which indicated at least five distinct energy pulses within the lahar …
Beware Of Ips In Sheep's Clothing: Measurement And Disclosure Of Ip Spoofing Vulnerabilities, Alden Douglas Hilton
Beware Of Ips In Sheep's Clothing: Measurement And Disclosure Of Ip Spoofing Vulnerabilities, Alden Douglas Hilton
Theses and Dissertations
Networks not employing destination-side source address validation (DSAV) expose themselves to a class of pernicious attacks which could be prevented by filtering inbound traffic purporting to originate from within the network. In this work, we survey the pervasiveness of networks vulnerable to infiltration using spoofed addresses internal to the network. We issue recursive Domain Name System (DNS) queries to a large set of known DNS servers world-wide using various spoofed-source addresses. In late 2019, we found that 49% of the autonomous systems we tested lacked DSAV. After a large-scale notification campaign run in late 2020, we repeated our measurements in …
Medium Conditons And Influence Mechanism Of High Salinity Mine Water Transfer And Storage By Deep Well Recharge, Li Xin, Sun Yajun, Chen Ge, Wang Houzhu, Zhang Zhijun
Medium Conditons And Influence Mechanism Of High Salinity Mine Water Transfer And Storage By Deep Well Recharge, Li Xin, Sun Yajun, Chen Ge, Wang Houzhu, Zhang Zhijun
Coal Geology & Exploration
In the arid and semi-arid regions of the Western China, there is not only a shortage of water resources, but also the problems of large mine water inflow and high salinity of mine water. In order to reduce the waste of water resources in the mining activities and protect water ecological environment in the region, it is proposed to treat the mine water by deeper well recharge to the aquifers under the coal seam based on the theories and technical methods such as mine water transfer and storage, water-preserving mining and coal-water dual resource coordinated mining. A test well project …
Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu
Hydrochemical Characteristics And Genetic Mechanism Of High Tds Groundwater In Xinjulong Coal Mine, Zhang Yuzhuo, Xu Zhimin, Zhang Li, Lyu Weikui, Yuan Huiqing, Zhou Lijie, Gao Yating, Zhu Lulu
Coal Geology & Exploration
Based on historical water quality data and sampling test results, using Piper three-line diagram, correlation analysis, hydrogen and oxygen isotope, Gibbs diagram, ion ratio and saturation index, etc., the hydrochemical characteristics and genetic mechanism of the groundwater with high TDS in Xinjulong Coal Mine area were explored. The results show that with the proceeding of mine construction and coal mining, the water chemistry environment in the study area has changed. The water chemistry type is no longer a single SO4-Na type, with SO4·HCO3-Na and SO4-Ca·Mg type appearing in the deep limestone water. …
Gas Emission-Based Determination Of The Reasonable Driving Speed In Coal Roadway, Fu Shuai, Si Qingmin, Wang Qifei, Guo Xinyao, Zhang Hongtu
Gas Emission-Based Determination Of The Reasonable Driving Speed In Coal Roadway, Fu Shuai, Si Qingmin, Wang Qifei, Guo Xinyao, Zhang Hongtu
Coal Geology & Exploration
Scientific determination of the tunneling speed is an important prerequisite for the safe and efficient production in coal mines with high gas and outburst. In order to determine the reasonable driving speed of coal roadway and reduce the occurrence of dynamic disasters in coal roadway driving, the distribution law of gas in roadway head was analyzed, the mathematical model was established. Gas emission characteristics were also analyzed at different driving speeds based on the model. Taking Jinhui Wanfeng Coal Mine as an example, the reasonable driving speed was determined in this coal mine based on its gas emission characteristics. Results …
Collapse Filling-Based Technology Of Weakening And Danger-Solving By Staged Fracturing In Hard Roof, Zheng Kaige, Yang Junzhe, Li Bingang, Li Yanjun, Dai Nan, Yang Huan
Collapse Filling-Based Technology Of Weakening And Danger-Solving By Staged Fracturing In Hard Roof, Zheng Kaige, Yang Junzhe, Li Bingang, Li Yanjun, Dai Nan, Yang Huan
Coal Geology & Exploration
The working face is easy to induce dynamic disasters such as rock burst, coal and gas outburst, mine earthquake and hurricane in goaf under the condition of hard roof, which seriously threatens the safety of mine production. the pre-weakening and risk-solving technology of staged fracturing in hard roof is proposed based on the mode of advanced weakening by staged fracturing through open holes, combined with the synergetic support concept with "fracturing collapse body+coal pillar+load-bearing rock layer". By using the methods of theoretical analysis, technical research and development and engineering application, the crisis mechanism of advanced weakening of the staged fracturing …
Slippage Effect And The Seepage Mechanism Considering The Compaction And Embedding Action Of Proppant, Cheng Qiaoyun, Li Bobo, Li Jianhua, Gao Zheng, Wang Bin
Slippage Effect And The Seepage Mechanism Considering The Compaction And Embedding Action Of Proppant, Cheng Qiaoyun, Li Bobo, Li Jianhua, Gao Zheng, Wang Bin
Coal Geology & Exploration
Hydraulic fracturing technology is an effective method to improve the efficiency of coalbed methane drainage, but the universal embedding of proppant under stress will change the width of the fractures, which will affect the gas slippage effect and the permeability mechanism. In order to explore the gas slippage effect and coal seepage law under the background of hydraulic fracturing, the Hertzian contact theory is used to quantify the embedding depth of proppant, and the gas slippage coefficient calculation equation and permeability model of the combined effect of proppant and effective stress are constructed. The results show that under different gas …
Study On P-Wave Velocity And Mechanical Response Characteristic Of Rock In Coal Seam Roof With Supercritical Co2 Injection, Chen Chen, He Xingyi, Niu Qinghe, Yu Hongxu, Xie Xiangyu
Study On P-Wave Velocity And Mechanical Response Characteristic Of Rock In Coal Seam Roof With Supercritical Co2 Injection, Chen Chen, He Xingyi, Niu Qinghe, Yu Hongxu, Xie Xiangyu
Coal Geology & Exploration
Deep coal seam CO2 geological sequestration and enhanced CH4 recovery(CO2-ECBM) can both increase CBM recovery and achieve carbon emission reduction, possessing dual benefits of energy and environment. The geochemical reactions between supercritical CO2(ScCO2), water and coal seam roof can change its physical-mechanical properties and increase the risk of CO2 leakage. In this paper, taking the roof rock of No.3 coal seam in Hudi Mine from Qinshui Basin as the research area, the ScCO2-water-rock geochemical reaction simulation experiment was carried out to explore the geochemical reaction process of ScCO2 …
Discussion On Overburden Zoning Model After Mining And Its Engineering Significance, Lyu Yuguang, Qiao Wei, Cheng Jianyuan, Cui Ping
Discussion On Overburden Zoning Model After Mining And Its Engineering Significance, Lyu Yuguang, Qiao Wei, Cheng Jianyuan, Cui Ping
Coal Geology & Exploration
The mechanical state of overburden after mining is directly related to roof accidents and roof water disasters, so it is necessary to study the overburden structure after mining. The "New Four Zones" model of overburden structure is proposed: caving zone, fracture zone, bedrock separation zone and loose alluvium zone. Combined with the previous "Three Zones" model and "Four Zones" model, this paper makes a spatial comparative analysis to clarify the spatial relationship of the three zoning models. It discusses the scientific nature of the "New Four Zones" model in terms of the influence of mining on water level of the …
Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong
Optimization Of Regional Advanced Coal Floor Water Hazard Prevention And Control Technology And Its Application, Zheng Shitian, Ma Hewen, Ji Yadong
Coal Geology & Exploration
In order to optimize the grouting process, improve the effect of the technology, and promote its application, this paper presents an investigation on the application of the regional advanced coal floor water hazard prevention and control technology in Huaibei mining area. The investigation shows that the pressure control in low pressure diffusion and medium pressure strengthening stages plays a major role in controlling the total grouting volume, which directly affects the limestone aquifer reformation. The prediction formula for grouting volume for strata with different karst fractures can provide guidance to the grouting engineering design. In addition, the horizontal layout method …
Experimental Study On Visual System For Water-Blocking Process Of Hydrodynamic Roadway By Aggregate Pouring In Water Inrush Mine, Mou Lin
Coal Geology & Exploration
Blocking water of hydrodynamic roadway by aggregate pouring in water inrush mines is an important method for mine rescue. To study its mechanism, the experimental platform of similar simulation test was established based on such factors as water head height, flow rate, roadway size, inclination angle, roughness, aggregate particle size and perfusion speed. Based on the platform, single-hole and multi-hole pouring tests were carried out to analyze the movement and accumulation law of aggregate in hydrodynamic pathway. The results are as follows. Firstly, the accumulation body has the characteristics of migration and growth to the downstream during the normal pouring …
Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang
Performance Deterioration Law Of Retarded Cement Slurry And Its Mixed Slurry In Freezing Borehole Mud Replacement, Li Qiang, Wang Yansen, Wang Chunlin, Xu Shengji, Fan Zhiqiang
Coal Geology & Exploration
The mud replacement of freezing hole has become a necessary part of freezing shaft sinking in rock strata, but in the lowering process, the freezing pipe is prone to excessive slurry viscosity resistance, and even be locked, leading to borehole failure. In order to deeply understand the performance deterioration law of cement slurry and its mixture in deep hole environment, the laboratory tests of retarded cement slurry and mixed slurry are carried out respectively, taking the apparent viscosity as the measurement index and considering the factors such as curing time, temperature, water loss state and volume ratio of mixed slurry. …
Blending Interference Noise Separation Method Of Simultaneous Source Seismic Data Based On Multi-T-X Domain Combination, Yu Dai, Huang Dezhi, Sun Yuan, Yang Wenping
Blending Interference Noise Separation Method Of Simultaneous Source Seismic Data Based On Multi-T-X Domain Combination, Yu Dai, Huang Dezhi, Sun Yuan, Yang Wenping
Coal Geology & Exploration
With the increasing application of simultaneous source seismic data acquisition method in seismic oil and gas exploration, many scholars have studied the key technology of simultaneous source seismic data blending interference noise separation. So far, research on methods with higher fidelity is still needed. This article is based on the following assumptions: Normal Moveout Correction(NMO) in simultaneous source seismic data can enhance the linear distribution degree of reflection(especially in Common Middle Point(CMP) gather), and expand the distribution difference of reflection and blending interference noise; single domain separation of blending interference noise only aims at a certain distribution characteristic difference of …
Application Of Surface Nuclear Magnetic Resonance Technology In Detecting Water Abundance In Concealed Burnt Zone, Hou Enke, Fan Jiangwei, Gao Lijun, Wang Jianwen, Chen Dehai, Chi Baosuo, Wang Hongke
Application Of Surface Nuclear Magnetic Resonance Technology In Detecting Water Abundance In Concealed Burnt Zone, Hou Enke, Fan Jiangwei, Gao Lijun, Wang Jianwen, Chen Dehai, Chi Baosuo, Wang Hongke
Coal Geology & Exploration
The overlying bedrock composite aquifer(including weathered bedrock and burnt rock aquifer) in the concealed burnt zone of coal seams is one of the main threats to coal mining. It is of great significance to clarify the water enrichment of the concealed burnt zone for the prevention and control of coal mine water hazards. Ningtiaota Coal Mine, which has experienced a large water inrush accident, was used as the research object, and the Surface Nuclear Magnetic Resonance(SNMR) was used to detect the water enrichment of the aquifer in the concealed burnt area. The results show that there are two aquifers in …
Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao
Research On Three-Component Response Of Ground-Airborne Tem Considering Emission Current Waveform, Hou Yanwei, Guo Jianlei, Si Yinnyu, Jiang Tao
Coal Geology & Exploration
The ground-airborne TEM has received more and more attention in coal goaf exploration and other fields. In order to provide a theoretical basis for the processing and interpretation of ground-airborne transient electromagnetic data, it is necessary to study the influence of the transmitted current waveform parameter on the three-component response characteristics of ground-airborne TEM. Taking trapezoidal waves as an example, this article firstly studies the frequency distribution of different emission current waveform, and then investigates the effects of the rising edge time, pulse width and turn-off time of the transmitted waveform on the three-component magnetic field response of ground-air transient …
Research And Application Of Horizontal Wire-Line Directional Deviation Correction While Drilling, Wu Jinsheng, Huang Xiaolin, Jiang Bing, Zhang Chi, Wu Wanjiong
Research And Application Of Horizontal Wire-Line Directional Deviation Correction While Drilling, Wu Jinsheng, Huang Xiaolin, Jiang Bing, Zhang Chi, Wu Wanjiong
Coal Geology & Exploration
In wire-line core drilling of horizontal holes, the rotation axis of the drilling tool is not in a straight line with its own gravity direction; with the ground hole pressurized, the drilling trajectory will be deviated due to the soft and hard formation or the occurrence of the rock formation. At present, there is no effective way to achieve directional deviation correction while drilling. This paper studies the pushing, fixing and fishing technologies of small-diameter horizontal wire-line directional instruments while drilling. A set of horizontal rope directional drilling tools and directional technology are developed and applied in directional deviation correction …
Design And Application Of Pdc Bit For Large Diameter Directional Drilling Of Coal Seam Roof With Double Stage And Double Speed, Gao Xiaoliang, Ju Pei, Zhao Jianguo
Design And Application Of Pdc Bit For Large Diameter Directional Drilling Of Coal Seam Roof With Double Stage And Double Speed, Gao Xiaoliang, Ju Pei, Zhao Jianguo
Coal Geology & Exploration
The development of large diameter directional drilling technology has provided technical support for the extraction of gas in the upper corner of the goaf by "replacing roadway with borehole". At present, conventional large-diameter drilling mainly adopts the step-by-step hole-forming method, which solves the problem of insufficient power of large-diameter drilling equipment in underground coal mines. However, step-by-step reaming requires multiple times of lifting and lowering, long auxiliary time and intensive labor of the workers. In order to improve the drilling efficiency of large-diameter holes in the coal roof, a double stage drilling process with two speeds was developed. The process …