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2020

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Articles 6391 - 6420 of 10650

Full-Text Articles in Engineering

Research Progress In Ethane Dehydrogenation To Cogenerate Power And Value-Added Chemicals In Solid Oxide Fuel Cells, Yun Fan, Qi Wang, Jun Li, Jing-Li Luo, Xian-Zhu Fu Apr 2020

Research Progress In Ethane Dehydrogenation To Cogenerate Power And Value-Added Chemicals In Solid Oxide Fuel Cells, Yun Fan, Qi Wang, Jun Li, Jing-Li Luo, Xian-Zhu Fu

Journal of Electrochemistry

Increasing supplies of methane/shale gas have promoted global development of higher value chemicals such as ethylene production by ethane, which dramatically changes the markets of petrochemical industry. Clean and efficient transformation of ethane into higher value chemicals has far-reaching significance. Ethylene production through ethane steam cracking is a relatively matured technology for industrial production. However, the process consumes large amounts of energy and the presence of carbon deposition becomes a serious problem which is difficult to be solved. The cogenerated energy-chemicals solid oxide fuel cells have been widely studied because fuel gas can be converted into high-value chemicals via spontaneous …

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Construction And Electrochemical Performance Of Garnet-Type Solid Electrolyte/Al-Li Alloy Interface, Jia-Lin Ma, Hong-Chun Wang, Zheng-Liang Gong, Yong Yang Apr 2020

Construction And Electrochemical Performance Of Garnet-Type Solid Electrolyte/Al-Li Alloy Interface, Jia-Lin Ma, Hong-Chun Wang, Zheng-Liang Gong, Yong Yang

Journal of Electrochemistry

Garnet-type solid electrolyte is a newly developed Li ion conductor and promising in the application of all-solid-state batteries. However, Garnet is incompatible with Li anode, which restricts the application of Garnet-type solid batteries. In order to improve the contact between Garnet-type solid electrolyte and Li electrode, a composite anode which contains Al-Li alloy (Al4Li9) was prepared as an electrode. Al-Li alloy has many advantages such as easy preparation, low cost, simple post-treatment and high capacity. Garnet-type Li6.5La3Zr1.75W0.25O12 (LLZWO) was synthesized via solid-state reaction. Garnet solid electrolyte has …

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Honoring The Class Of 2020, Usu College Of Engineering Apr 2020

Honoring The Class Of 2020, Usu College Of Engineering

College of Engineering News

You’ve accomplished something extraordinary. By persevering through years of challenging work and training, you have earned one of the most versatile and valuable college degrees. In the last few months, you have shown tremendous agility in navigating an unprecedented public health crisis while completing a rigorous academic program and senior capstone requirements. You overcame this difficult hurdle, demonstrating the highest level of dedication and professionalism and accomplishing what no other class has done before. With your education and skillset from the College of Engineering, you are uniquely qualified to take on what comes next. You will enter an engineering workforce …

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Ensemble Malware Classification System Using Deep Neural Networks, Barath Narayanan Narayanan, Venkata Salini Priyamvada Davuluru Apr 2020

Ensemble Malware Classification System Using Deep Neural Networks, Barath Narayanan Narayanan, Venkata Salini Priyamvada Davuluru

Electrical and Computer Engineering Faculty Publications

With the advancement of technology, there is a growing need of classifying malware programs that could potentially harm any computer system and/or smaller devices. In this research, an ensemble classification system comprising convolutional and recurrent neural networks is proposed to distinguish malware programs. Microsoft's Malware Classification Challenge (BIG 2015) dataset with nine distinct classes is utilized for this study. This dataset contains an assembly file and a compiled file for each malware program. Compiled files are visualized as images and are classified using Convolutional Neural Networks (CNNs). Assembly files consist of machine language opcodes that are distinguished among classes using …

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Reliability-Calibrated Ann-Based Load And Resistance Factor Load Rating For Steel Girder Bridges, Francisco Garcia Apr 2020

Reliability-Calibrated Ann-Based Load And Resistance Factor Load Rating For Steel Girder Bridges, Francisco Garcia

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

This research aimed to develop a supplemental ANN-based tool to support the Nebraska Department of Transportation (NDOT) in optimizing bridge management investments when choosing between refined modeling, field testing, retrofitting, or bridge replacement. ANNs require an initial investment to collect data and train a network, but offer future benefits of speed and accessibility to engineers utilizing the trained ANN in the future. As the population of rural bridges in the Midwest approaching the end of their design service lives increases, Departments of Transportation are under mounting pressure to balance safety of the traveling public with fiscal constraints. While it is …

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Characterization Of Uranium Foil Irradiations At The Wsu Triga Reactor Using A New Reactor Model In Scale, Kimberly A. Hinrichs Apr 2020

Characterization Of Uranium Foil Irradiations At The Wsu Triga Reactor Using A New Reactor Model In Scale, Kimberly A. Hinrichs

Nuclear Engineering ETDs

A new reactor model of the Washington State University TRIGA was developed in the SCALE neutron transport code, and its fidelity was verified by comparison to MCNP and available data for several reactor parameters. The model was used to characterize irradiations designed to produce the short-lived actinides 237U and 239U, two key isotopes for nuclear forensics. These short-lived actinides, their decay daughters 237Np and 239Pu, and total fissions (via 99Mo) were measured in irradiated foils at Los Alamos National Laboratory and other labs with good agreement among parent/daughter pairs and among labs. The laboratory-measured isotope …

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Applications Of The Negatively-Charged Silicon Vacancy Color Center In Diamond, Forrest A. Hubert Apr 2020

Applications Of The Negatively-Charged Silicon Vacancy Color Center In Diamond, Forrest A. Hubert

Optical Science and Engineering ETDs

The spatial resolution and fluorescence signal amplitude in stimulated emission depletion (STED) microscopy is limited by the photostability of available fluorophores. Here, we show that negatively-charged silicon vacancy (SiV) centers in diamond are promising fluorophores for STED microscopy, owing to their photostable, near-infrared emission and favorable photophysical properties. A home-built pulsed STED microscope was used to image shallow implanted SiV centers in bulk diamond at room temperature. We performed STED microscopy on isolated SiV centers and observed a lateral full-width-at-half-maximum spot size of 89 ± 2 nm, limited by the low available STED laser pulse energy (0.4 nJ). For a …

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Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, Tami M. Brown-Bandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda Apr 2020

Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, Tami M. Brown-Bandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Low-cost depth-cameras have been used in many agricultural applications with reported advantages of low cost, reliability and speed of measurement. However, some problems were also reported and seem to be technology related, so understanding the limitations of each type of depth camera technology could provide a basis for technology selection and the development of research involving its use. The cameras use one or a combination of two of the three available technologies: structured light, time-of-flight (ToF), and stereoscopy. The objectives were to evaluate these different technologies for depth sensing, including measuring accuracy and repeatability of distance data and measurements at …

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Change Of Exposure Time Mid-Test In High Temperature Dic Measurement, Thinh Quang Thai, Adam J. Smith, Robert J. Rowley, Paul R. Gradl, Ryan B. Berke Apr 2020

Change Of Exposure Time Mid-Test In High Temperature Dic Measurement, Thinh Quang Thai, Adam J. Smith, Robert J. Rowley, Paul R. Gradl, Ryan B. Berke

Mechanical and Aerospace Engineering Faculty Publications

Performing digital image correlation (DIC) at extreme temperatures has been greatly challenging due to the radiation which saturates the camera sensor. At such high temperatures, the light intensity emitted from an object is occasionally so powerful that the acquired images are overwhelmingly saturated. This induces data loss, potentially ruining the test, thus requiring the user to restart the test. For this reason, selection of an appropriate camera sensitivity plays a crucial role prior to beginning the test. Exposure time is a factor contributing to camera sensitivity and it is the easiest setting to manipulate during the test since it introduces …

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Designing An Adjustable And Transportable Staircase, Allison Currey Apr 2020

Designing An Adjustable And Transportable Staircase, Allison Currey

Undergraduate Honors Thesis Projects

People climb stairs every day, whether it is at work, a store, or at home; however, there are populations such as people who are elderly, with pathologies, with Parkinson’s disease, or have suffered from a stroke that see climbing the stairs as a challenging task and it decreases their mobility and quality of life. Factors such as muscle weakness, strategy, and balance have been previously investigated in these populations during stair climbing. However, few studies have researched how stair climb ability, balance, and perception of difficulty are influenced by step height. The objective of this thesis is to design a …

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Ato Mode-Based Modular Platform Development Of Variable Luffing Crawler Drilling Rig Used In Underground Coal Mine, Song Haitao, Yao Ningping, Yao Yafeng, Han Jian, Peng Tao Apr 2020

Ato Mode-Based Modular Platform Development Of Variable Luffing Crawler Drilling Rig Used In Underground Coal Mine, Song Haitao, Yao Ningping, Yao Yafeng, Han Jian, Peng Tao

Coal Geology & Exploration

With the continuous popularization of customized crawler rigs in coal mines, the variety and specifications of crawler rigs have been further refined, diversified and complicated, and the modular platform of variable luffing crawler rigs has been successfully developed. The four key steps in the development of modular platform were analyzed: the construction of modular platform, the rational division and development of modular components, the integration and development of modular components, the modular customization model for customers based upon the proposed ATO-based model. The application results show that the establishment of the variable luffing crawler rig modular platform shortens respond to …

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Development Situation And Prospect Of Luffing Mechanism Of Drilling Rig In Underground Coal Mine, Yao Yafeng, Yao Ningping, Peng Tao Apr 2020

Development Situation And Prospect Of Luffing Mechanism Of Drilling Rig In Underground Coal Mine, Yao Yafeng, Yao Ningping, Peng Tao

Coal Geology & Exploration

The luffing mechanism of drilling rig is used to adjust the opening parameters of the borehole, that is, azimuth angle, inclination angle, and height. According to the structural differences of different types of drilling rig and the construction characteristics of borehole in underground coal mine, this paper summarizes the adjustment requirements to opening parameters and proposes the research goal, which can rapidly and accurately adjust the parameters of the borehole and safeguard the stability of drilling construction. It is concluded that the luffing mechanism of drilling rig in underground coal mine has overall characteristics of small size, large adjustment range …

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Key Technology For Rapidly Drilling Large Diameter Destressing-Drillhole In Rockburst Coal Seam, Wei Hongchao, Wang Yi, Wang Bo Apr 2020

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 …

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Foam Drilling Technology And Application For Broken Soft Coal Seam In Underground Coal Mine, Ji Qianhui, Dong Mengmeng, Liu Jianlin, Shi Lei Apr 2020

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 …

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Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin Apr 2020

Development Of Small Diameter Hydraulic Agitator With Cable For Directional Drilling In Underground Coal Mine, Wang Li, Xu Baolong, Wang Yi, Huang Hanjing, Jia Mingqun, Ma Bin

Coal Geology & Exploration

Aiming at the problems of large drilling pressure, low drilling efficiency and limited hole depth caused by the backing effect of drill string during deep hole directional drilling in underground coal mine, the technical idea of using hydraulic agitator was proposed. The ø89 mm small diameter hydriculic agitator was designed based on valve principle, the exciting force, excitation frequency were identified, and the cabled sub was developed. The performance parameters of hydraulic agitator with disc spring and cylindrical spring were tested. The results show that when the flow rate of 300 L/min the disc spring hydraulic agitator has the maximum …

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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 Apr 2020

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 …

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Discussion And Application Of Geological Evaluation Index Of Scarce Coal Injected Into Blast Furnace, Qiao Junwei, Li Zhengyue, Chen Meiying, Lyu Jun’E Apr 2020

Discussion And Application Of Geological Evaluation Index Of Scarce Coal Injected Into Blast Furnace, Qiao Junwei, Li Zhengyue, Chen Meiying, Lyu Jun’E

Coal Geology & Exploration

Coal injected into blast furnace can reduce the use of coke, is an important technical measure to reduce the production cost and improve the economic benefit of modern blast furnace. From the influential factors of quality of coal injected into blast furnace and on the basis of evaluation of quality of high-quality coal and scarce coal, the geological evaluation indexes and the grading parameters of scarce coal injected into blast furnace were discussed. The evaluation indexes of coal quality for blast furnace are divided into process index and economic index. Process index is the key index to determine whether coal …

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Solid-Liquid Migration Of Molybdenum In Stone Coal And Coal Ash In Southern Shaanxi, Zhang Weiguo, Li Huantong, Wang Feng, Yang Fu, Teng Jinxiang Apr 2020

Solid-Liquid Migration Of Molybdenum In Stone Coal And Coal Ash In Southern Shaanxi, Zhang Weiguo, Li Huantong, Wang Feng, Yang Fu, Teng Jinxiang

Coal Geology & Exploration

Molybdenum is a typical environmental sensitive element, and also a potential rare metal element. In order to find out the content characteristics of molybdenum in raw stone coal and coal ash and the migration rule between solid and liquid, stone coal and coal ash in southern Shaanxi Province were selected as the research object, and the molybdenum content in samples was analyzed by ICP-MS. To analyse the leaching rate of molybdenum from stone coal and coal ash in four different liquids, pure water, scid, alkaline and mine drainage were selected to simulate soaking experiment. The results show that the content …

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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 Apr 2020

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 …

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Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin Apr 2020

Numerical Simulation Of Layer-Crossing Propagation Behavior Of Hydraulic Fractures At Coal-Rock Interface, Li Haozhe, Jiang Zaibing, Shu Jiansheng, Fan Yao, Du Tianlin

Coal Geology & Exploration

Based on the analysis of coal-rock interface, the vertical propagation behavior of hydraulic fractures at coal-roof interface was studied by using finite element method. The influence of some geological and engineering factors on fracture layer-crossing behavior was analyzed. Results have shown that in-situ stress and shear strength of coal-rock interface are the two main factors affecting the fracture propagation at the coal-rock interface. Greater vertical stress difference coefficient and interfacial shear strength make fractures more easier for crossing the interface. Meanwhile, the difference of elastic modulus and tensile strength between coal and rock has less effect on the fracture vertical …

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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 Apr 2020

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 …

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Effect Of White Rot Fungi Pretreatment On Methane Production From Anaerobic Fermentation Of Coal, Zhang Huaiwen, Huang Song, Yan Xiatong, Zhao Shufeng, Zhang Minglu, Xia Daping Apr 2020

Effect Of White Rot Fungi Pretreatment On Methane Production From Anaerobic Fermentation Of Coal, Zhang Huaiwen, Huang Song, Yan Xiatong, Zhao Shufeng, Zhang Minglu, Xia Daping

Coal Geology & Exploration

To investigate the effect of white rot fungi pretreatment on methane production from anaerobic fermentation of coal, fermentation experiments of biogas production were conducted using long flame coal. The coal samples pretreated with white rot fungi were the experimental group(EG), and original untreated coal samples were the control group(CG). The COD(chemical oxygen demand) mass concentration, activity of coenzyme F420, and changes of coal morphology were measured using potassium dichromate method, ultraviolet spectrophotometry, and SEM, respectively. The results showed the following: The total gas production and conversion rate in the EG and CG were 2 322.00 mL and 5.10%, 1 330.20 …

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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 Apr 2020

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 …

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Preparation Of Underwater Quick-Set And Expansion Polyurethane Grouting Material And Its Properties, Yang Zhu, Xue Ren, Wang Jun, Lan Zhili Apr 2020

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 …

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Classification Of Hidden Faults In Coal Seam Floor And Measures For Water Inrush Prevention, Liu Zewei, Liu Qisheng, Liu Yang Apr 2020

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 …

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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 Apr 2020

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 …

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Negative Power Rock Strength Criterion Under Conventional Triaxial Compression, Li Bin, Wang Daguo Apr 2020

Negative Power Rock Strength Criterion Under Conventional Triaxial Compression, Li Bin, Wang Daguo

Coal Geology & Exploration

In order to evaluate accurately the rock strength under different confining pressures, a negative power rock strength criterion was proposed according to the upward convex nonlinear relationship between deviator stress and confining pressure during rock failure. The accuracy of the proposed criterion was compared with Mohr-Coulomb criterion and Hoek-Brown criterion. The results showed that the parameters of the negative power criterion are less sensitive to the range of confining pressure, and the negative power criterion could evaluate rock triaxial strength with higher precision. Meanwhile, the applicability of the proposed criterion was verified by using an extensive database of rock triaxial …

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Influencing Factors Of Thermal Conductivity Of Cementing Materials For Geothermal Wells, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang Apr 2020

Influencing Factors Of Thermal Conductivity Of Cementing Materials For Geothermal Wells, Zhang Hao, Xu Shuanhai, Yang Yu, Han Yongliang, Zhang Weidong, Li Yongqiang

Coal Geology & Exploration

The thermal conductivity of cementing materials is one of the factors that affect the heat removal effect of geothermal wells. In order to improve the thermal conductivity of cementing materials for geothermal wells, orthogonal test was used to study the thermal conductivity of cementing materials based on the AHP-CRITIC mixed weighting method and range analysis. The results show that the thermal conductivity of cementing materials can be improved by adding natural flake graphite, iron powder and quartz sand. The content of graphite and the ratio of water to solid are the primary and secondary factors that affect the comprehensive properties …

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Combining Eye Tracking And Verbal Response To Understand The Impact Of A Global Filter, Franceli L. Cibrian, Jazette Johnson, Viseth Sean, Hollis Pass, Louanne Boyd Apr 2020

Combining Eye Tracking And Verbal Response To Understand The Impact Of A Global Filter, Franceli L. Cibrian, Jazette Johnson, Viseth Sean, Hollis Pass, Louanne Boyd

Engineering Faculty Articles and Research

Visual attention guides the integration of two streams: the global, that rapidly processes the scene; and the local, that processes details. For people with autism, the integration of these two streams can be disrupted by the tendency to privilege details (local processing) instead of seeing the big picture (global processing). Consequently, people with autism may struggle with typical visual attention, evidenced by their verbal description of local features when asked to describe overall scenes. This paper aims to explore how one adult with autism see and understand the global filter of natural scenes.

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Progress Of Drilling Technologies And Equipments For Complicated Geological Conditions In Underground Coal Mines In China, Yao Ningping, Wang Yi, Yao Yafeng, Song Haitao, Wang Li, Peng Tao, Sun Xinsheng Apr 2020

Progress Of Drilling Technologies And Equipments For Complicated Geological Conditions In Underground Coal Mines In China, Yao Ningping, Wang Yi, Yao Yafeng, Song Haitao, Wang Li, Peng Tao, Sun Xinsheng

Coal Geology & Exploration

According to the drilling technology requirements and problems under complicated geological conditions, such as broken soft coal seam, hard rock, rockburst strata, fractured zone, water-sensitive strata, etc, the research and application of drilling technology and screen pipe protection in broken soft coal seam, comb-like directional drilling technology in broken soft coal seam, high-level directional drilling technology in complicated roof strata, full-section across-layer drilling technology of hard rock, and drilling technology for pressure relief in rockburst strata were summed. This paper puts forward the research approaches of the technology and equipment of double-pipes directional drilling and rotary directional drilling in broken …

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