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Articles 60901 - 60930 of 197987

Full-Text Articles in Engineering

Raman Spectrum Characteristic And Structural Evolution Of High Rank Coalscryptocrystalline Graphite, Li Huantong, Wang Nan, Zhu Zhirong, Fan Jingjing, Zhang Weiguo Feb 2020

Raman Spectrum Characteristic And Structural Evolution Of High Rank Coalscryptocrystalline Graphite, Li Huantong, Wang Nan, Zhu Zhirong, Fan Jingjing, Zhang Weiguo

Coal Geology & Exploration

Raman spectroscopy can reflect the order degree and structural defects of carbon materials, and can be used to characterize the structural changes during the evolution of high rank coal-cryptocrystalline graphite, and analyze the relationship between Raman parameters of coal with different deformation and metamorphic degrees and the spacing of surface network(d002). The results showed that: (1) there was stepped variation between the G peak position and d002, but the graphite and high rank coal could be distinguished well. The S2 peak, the full width at half maximum of D1 and G had a good linear relationship with d002; (2) the …

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Characteristics And Sedimental Control Of Mine Water Outflow In Hujirt Mining Area, Liang Xiangyang, Yang Jian, Cao Zhiguo Feb 2020

Characteristics And Sedimental Control Of Mine Water Outflow In Hujirt Mining Area, Liang Xiangyang, Yang Jian, Cao Zhiguo

Coal Geology & Exploration

Hujirt mining area in Ordos basin is a deep-buried Jurassic coalfield with high water pressure, large water volume and uneven water abundance. Each mine is facing serious pressure of mine water hazard prevention and control. In order to clarify the water outflow conditions and main controlling factors of the coal seam roof of the mine in this area, the research on geological deposit and water-producing horizon of roof boreholes, water-inrush from boreholes and water-inrush from working face was carried out. The results showed that within the water conducting fractured zone of Hujirt mining area, there are mainly meandering river sedimentary …

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Development And Application Of Macroscopic And Mesoscopic Analytical Testing Instrument For Reinforcement-Soil Interface Characteristics, Yi Fu, Du Changbo, Wang Zhengyun, Yu Ben Feb 2020

Development And Application Of Macroscopic And Mesoscopic Analytical Testing Instrument For Reinforcement-Soil Interface Characteristics, Yi Fu, Du Changbo, Wang Zhengyun, Yu Ben

Coal Geology & Exploration

To analyze the interaction characteristics of soil-reinforcement interface more comprehensively, an experimental instrument for macro-and micro-analysis of interface characteristics of visible reinforced soils was developed and can be used for direct shear and pull-out tests with different geosynthetics and fillers. The instrument improves the size of test box, facilitates the comparative analysis of the two tests, and has an image recording system which enables the microscopic analysis of test process. The direct shear and pull-out tests of geosynthe­tics(geogrid and geotextile) reinforced tailings sand were carried out with the newly developed apparatus. The results show that the interface parameters(pseudo-cohesion and pseudo …

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Table Of Contents, The Editors Feb 2020

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Status And Development Prospect Of The Coal-Based Graphite Resources In Fujian Province, Chen Quanlin, Cheng Qiao, Deng Ruijin, Lin Xiaoyan, Wang Lu, Ding Zhengyun, Li Yang, Cheng Qiao, Lin Xiaoyan, Cao Daiyong Feb 2020

Status And Development Prospect Of The Coal-Based Graphite Resources In Fujian Province, Chen Quanlin, Cheng Qiao, Deng Ruijin, Lin Xiaoyan, Wang Lu, Ding Zhengyun, Li Yang, Cheng Qiao, Lin Xiaoyan, Cao Daiyong

Coal Geology & Exploration

The coal-based graphite of Fujian Province occurs in the coal-bearing strata of the Middle Permian Tong ziyan Formation, is formed by the further metamorphism of the anthracite of the Tongziyan Formation under high temperature and pressure, and belongs to the aphanitic graphite. By investigating the distribution characteristics of coal-based graphite in Fujian Province, it was found that most of the coal-based graphite mines and exploration areas are in an unmined or stopped state, and production and sale in most mining areas are in the form of coal mining, causing resources waste. In order to rationally develop and use coal-based graphite …

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Metallogenic Law And Prospecting Direction Of Coal-Based Graphite In Hunan Province, Mo Jiafeng, Zhao Xunlin, Zhu Wenqing, Li Huantong Feb 2020

Metallogenic Law And Prospecting Direction Of Coal-Based Graphite In Hunan Province, Mo Jiafeng, Zhao Xunlin, Zhu Wenqing, Li Huantong

Coal Geology & Exploration

There are many intrusive rocks and complex structures in Hunan Province.In order to study the mineralization law of coal-based graphite, on the basis of collecting the existing geological data, drawing on the characteristics of coal-based graphite deposits at home and abroad, combining the distribution characteristics and development status of graphite resources in Hunan Province, using geological surveys, production well surveys, sampling tests, etc., the geological characteristics of the ore bodies in the existing mining areas around the two granite bodies were studied, the genetic type and ore controlling factors of the graphite deposits were explored, the genetic type is contact …

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Occurrence And Origin Of Graphite Microcrystal In Meta-Anthracite, Li Jiuqing, Qin Yong, Chen Yilin Feb 2020

Occurrence And Origin Of Graphite Microcrystal In Meta-Anthracite, Li Jiuqing, Qin Yong, Chen Yilin

Coal Geology & Exploration

Microcrystalline graphite occurs widely in meta-anthracite,to analyse the occurrence characteristics and genesis of graphite microcrystal, by methods of optical microscope, scanning electron microscope and transmission electron microscope, the optical properties, material composition and crystal structure of graphite microcrystal in Yong’an coal field of Fujian Province were characterized, and their genesis was preliminarily discussed. The results show that the graphite microcrystal in coal occurs mainly in micro cracks and cavities, and most of them have fibrous microstructure similar to petroleum coke, with bubble membrane structure. The maximum reflectivity of the microcrystal ranges from 9.29% to 10.83% and significantly stronger than the …

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The Tectonic Framework And Controlling Mechanism Of Coal-Based Graphite In Lutang Mining Area, Hunan Province, Wang Lu, Peng Yangwen, Cao Daiyong, Ding Zhengyun, Mo Jiafeng Feb 2020

The Tectonic Framework And Controlling Mechanism Of Coal-Based Graphite In Lutang Mining Area, Hunan Province, Wang Lu, Peng Yangwen, Cao Daiyong, Ding Zhengyun, Mo Jiafeng

Coal Geology & Exploration

Lutang mining area, one of the famous coal-based graphite mining areas in China, is controlled by both the magmatic intrusions and tectonic activities. Both the graphitization of coal and occurrence are closely related to the tectonic framework. To study the influence of tectonic activity on the formation of coal-based graphite, based on the filed geological survey, observation under microscope, X-ray diffraction and Raman spectroscopy experiments, structural characteristics of the research area and characteristics of coal-based graphite were analyzed. The effect of structural control of ore on the coal-based graphite was discussed in this paper. The tectonic framework of the study …

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The Control Of Mineralization And Occurrence Of Coal-Based Graphite By Tectonic-Heat In Zhangping-Datian Area, Fujian, Ding Zhengyun, Wang Lu, Zeng Huan, Li Yang, Chen Quanlin, Deng Ruijin, Cheng Qiao, Lin Xiaoyan, Cao Daiyong Feb 2020

The Control Of Mineralization And Occurrence Of Coal-Based Graphite By Tectonic-Heat In Zhangping-Datian Area, Fujian, Ding Zhengyun, Wang Lu, Zeng Huan, Li Yang, Chen Quanlin, Deng Ruijin, Cheng Qiao, Lin Xiaoyan, Cao Daiyong

Coal Geology & Exploration

Datian-Zhangping area, Fujian Province, is located in the east coast Pacific tectonic belt, magmatic hydrothermal processes and complex tectonic deformation patterns in different periods provide favorable conditions for the formation of abundant graphite deposits in this area. In order to find out the metallogenic control factors and distribution law of coal-based graphite in Datian-Zhangping area, through proximate analysis, elemental analysis, X-ray diffraction and Raman spectroscopy, the graphitization characteristics of coal and coal-based graphite with different metamorphic degree in different mining areas were studied. The samples with different deformation characteristics were divided into three types: coal-based graphite, coal-based semi-graphite and graph-itized …

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Molecular Structure Characteristics And Model Construction Of Anthracite In Jarud, Zhang Shuai, Ma Rujia, Liu Lu, Zhang Hao, Liu Qinfu Feb 2020

Molecular Structure Characteristics And Model Construction Of Anthracite In Jarud, Zhang Shuai, Ma Rujia, Liu Lu, Zhang Hao, Liu Qinfu

Coal Geology & Exploration

To construct the macromolecular structure model of anthracite in Jarud of Inner Mongolia, the macromolecule structure of anthracite in this area was investigated using the methods of proximate analysis, ultimate analysis, carbon nuclear magnetic resonance(13C-NMR), high resolution transmission electron microscope(HRTEM), and X-ray photoelectric spectrometry(XPS). The results showed that aromatic carbon was the main component of macromolecule structure. Aliphatic carbon existed mainly in the form of short aliphatic chains and naphthenic hydrocarbons. The oxygen-containing functional groups in macromolecule structure of anthracite existed in the form of phenolic hydroxyl group and ether oxygen group. The nitrogen atoms were mainly in the form …

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Organic Nitrogen Forms Of Different Rank Coals In Handan-Fengfeng Mining Area, China, Hao Guoqiang, Hu Sherong Feb 2020

Organic Nitrogen Forms Of Different Rank Coals In Handan-Fengfeng Mining Area, China, Hao Guoqiang, Hu Sherong

Coal Geology & Exploration

Nitrogen is one of the common elements in coal. The occurrence forms of nitrogen in coal are various and vary with coal rank. Based on X-ray photoelectron spectroscopy (XPS), taking Handan-Fengfeng mining area as an example, organic nitrogen forms of different rank coals(Rran = 1.08%–3.67%) were studied, and the variation of the relative abundance of each organic nitrogen with rank was further discussed. The results show that four kinds of nitrogen forms are considered for the coals according to binding energies of N 1s XPS sub-peaks, corresponding to N-6, N-5, N-Q and N-X. N-5 is the most abundant organic nitrogen …

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Key Geological Factors And Evaluation Methods For Huge Low-Rank Coalbed Methane Reservoirs：Taking Bayanhua Depression In Erlian Basin As An Example, Yao Haipeng, Lyu Weibo, Wang Kaifeng, Li Ling, Li Wenhua, Lin Haitao, Li Fengchun, Li Zheng Feb 2020

Key Geological Factors And Evaluation Methods For Huge Low-Rank Coalbed Methane Reservoirs：Taking Bayanhua Depression In Erlian Basin As An Example, Yao Haipeng, Lyu Weibo, Wang Kaifeng, Li Ling, Li Wenhua, Lin Haitao, Li Fengchun, Li Zheng

Coal Geology & Exploration

In order to evaluate the potential of low rank CBM resources with large thickness, Bayanhua depression in Erlian basin is studied. By studying the genesis of CBM, buried depth of coal seam, thickness of coal seam, physical properties of coal reservoir, gas content, hydrogeology and cap rock, the key geological elements of thick and low coal rank coal reservoirs are summarized. Furthermore, a new low rank CBM resource potential evaluation method is established, and the favorable and target zones for CBM exploration and development in Bayanhua depression are delineated. The results show that the main coal-bearing strata in Bayanhua depression …

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Gas Content Modeling Of No.3 Coal Seam In District 3 Of Southern Shizhuang Block, Zhou You, Zhang Songhang, Tang Shuheng, Yu Tiancheng, Feng Zhao Feb 2020

Gas Content Modeling Of No.3 Coal Seam In District 3 Of Southern Shizhuang Block, Zhou You, Zhang Songhang, Tang Shuheng, Yu Tiancheng, Feng Zhao

Coal Geology & Exploration

The gas content of coal seam has a direct impact on the development of coalbed methane. The gas content of coal seam in southern Shizhuang block is high, but there are many inefficient wells in the development process, and the 3D geological modeling of gas content can help determine the influence of gas content on the production of CBM wells. In this paper, the research object is the No.3 coal seam in southern Shizhuang block. Calculated gas content from linear multivariate regression by using parameters of ash content, volatile matter content and fixed carbon content and simple burial depth matches …

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“Scenario-Response”-Based Emergency Decision-Making Mechanism Of Mine Water Inrush Disaster, Lian Huiqing, Yang Junwen, Han Ruigang, Meng Lu, Han Yong Feb 2020

“Scenario-Response”-Based Emergency Decision-Making Mechanism Of Mine Water Inrush Disaster, Lian Huiqing, Yang Junwen, Han Ruigang, Meng Lu, Han Yong

Coal Geology & Exploration

The urgency, complexity and uncertainty of mine flood accidents determine that traditional emergency decision-making models are difficult to meet the requirements of efficient emergency rescue. Using the “scenario-response” model for emergency decision-making of mine flood accidents can effectively solve the timely real-time decision-making of specific disaster scenario after disasters occur. Using a multi-case analysis method to analyze 11 typical mine flood accidents in recent years, based on the general structural description of the accident, six elements of the mine flood scenario were summarized(inrush water source, water inrush channel, water inrush position, water output, submerged range, living space) as the scenario …

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Hydrochemical Formation Mechanism And Transmissivity-Impermeability Analysis Of Karst Groundwater On Both Sides Of Fault F104 In Gubei Coal Mine In Huainan, Zheng Zhuyan, Xu Guangquan, Yang Tingting, Yu Shitao, Zhang Haitao Feb 2020

Hydrochemical Formation Mechanism And Transmissivity-Impermeability Analysis Of Karst Groundwater On Both Sides Of Fault F104 In Gubei Coal Mine In Huainan, Zheng Zhuyan, Xu Guangquan, Yang Tingting, Yu Shitao, Zhang Haitao

Coal Geology & Exploration

It is of great practical significance for the prevention and control of groudwater hazards in North China type coalfield to judge transmissivity-impermeability of faults by using karst hydrochemical characteristics of two fault walls. Taking karst groundwater of Taiyuan Formation on both sides of fault F104 in Gubei coal mine as the research object, and based on the analysis of the hydrogeological conditions of two fault walls, main components sources and water-rock interaction differences were analyzed by using Piper trilinear diagram, ion combination ratio and principal component methods. Reverse hydrochemical simulation of karst groundwater was conducted by using PHREEQC software. …

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Mining Response And Dynamic Reinforcement For Narrow Coal Pillar Next To Goaf In Working Face 1402 Of Xin’An Coal Mine, Wang Beifang, Liang Bing, Liu Wei, Zhang Jing, Chi Haibo, Liu Yahui Feb 2020

Mining Response And Dynamic Reinforcement For Narrow Coal Pillar Next To Goaf In Working Face 1402 Of Xin’An Coal Mine, Wang Beifang, Liang Bing, Liu Wei, Zhang Jing, Chi Haibo, Liu Yahui

Coal Geology & Exploration

with the increase of integrating coal mines under national coal de-capacity policy, the mining instability phenomenon of narrow coal pillar next to goaf is increasingly prominent, which has seriously restricted the safety and efficient production in coal mines. Therefore, stability control engineering problem of narrow coal pillar next to goaf, near No.5 drilling field on air return roadway of repeated mining face 1402 in Xin'an coal mine was as study object, a method of combining numerical simulation and theoretical analysis was used to explore the mining disturbance response characteristics of narrow coal pillar stability next to goaf, near No.5 drilling …

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Anisotropic Shear Behavior Of Rock Joint Based On 3d Printing Technology, Xu Xunhui, Zhang Guobiao, Bao Han, Yan Changgen Feb 2020

Anisotropic Shear Behavior Of Rock Joint Based On 3d Printing Technology, Xu Xunhui, Zhang Guobiao, Bao Han, Yan Changgen

Coal Geology & Exploration

Topography is an important factor affecting the shear behavior of joint. Furthermore, there are certain connections between the anisotropy of topography and the anisotropy of shear behavior. In this study, 3D laser scanning technology and 3D printing technology were used to make molds for simulating the topography of natural joint. Then, the cement mortar samples with dimension of 100 mm×100 mm×150 mm were cast, and shear tests with different shear directions under different normal stresses were conducted. The results indicate that obvious anisotropy has been shown in the joint shear behavior, which is reflected in the peak shear strength and …

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Three-Dimensional Stress Evolution And Comprehensive Treatment Technology For Super-Long Working Face Across Abandoned Roadway With Large Section, Wang Yan, Xiong Zuqiang, Zhao Gaobo Feb 2020

Three-Dimensional Stress Evolution And Comprehensive Treatment Technology For Super-Long Working Face Across Abandoned Roadway With Large Section, Wang Yan, Xiong Zuqiang, Zhao Gaobo

Coal Geology & Exploration

In order to solved the problem of super-long working face across abandoned roadway with large section, which is easy to cause rib spalling and roof falling, based on a super-long working face in Chengzhuang mine of Jincheng, a three-dimensional model of abandoned with large section roadway was established. The roof of working face was divided into three parts: coal pillar roof, abandoned roadway roof and mining area roof. The criterion of pillar instability was deduced and the roof stress evolution process of large section abandoned roadway was analyzed by FLAC3D numerical simulation. The results show that when the W …

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Multidimensional Deformation Monitoring Using Insar Technology In Yuxian Mining Area, Du Jiantao, Yan Li, Zhao Chaoying Feb 2020

Multidimensional Deformation Monitoring Using Insar Technology In Yuxian Mining Area, Du Jiantao, Yan Li, Zhao Chaoying

Coal Geology & Exploration

Yuxian County in Hebei Province is one of the largest mining areas in North China. This area has been suffering serious ground deformation due to underground mining activity, which not only threatens mining safety, but also seriously damages local ecological environment. To obtain the surface deformation map of the overall mining area and to analysis the spatiotemporal evolution features, 61 C-band descending track and ascending track Sentinel-1A/B images from July 2017 to September 2018 were processed based on Interferometric Synthetic Aperture Rader(InSAR) technique. In addition, the two-dimensional deformation time series of Xixizhuang mine were obtained by using the multi-dimensional deformation …

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Ruger Approximate Formula-Based Prediction Of Fractured Reservoir, Wu Shanshan, Gao Gang, Gui Zhixian, Wang Peng, Li Chengyi Feb 2020

Ruger Approximate Formula-Based Prediction Of Fractured Reservoir, Wu Shanshan, Gao Gang, Gui Zhixian, Wang Peng, Li Chengyi

Coal Geology & Exploration

The azimuthal anisotropy of pre-stack P-wave is the most widely used method to detect fracture. This method mainly uses the long-axis and minor axis information of the ellipse fitted by the AVAZ seismic data to evaluate the fracture. When applying it in practice, it is considered that the variation of AVAZ response characteristics in the fractured reservoirs is just determined by the anisotropic parameters, and the influence of non-anisotropic parameters is not taken into account, which leads to the multi-solution of fracture evaluation. In order to improve the accuracy of this fracture evaluation technology, we started with the model analysis, …

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Frequency Dispersion Mechanism Of Complex Resistivity Of Coal, Guo Yuehui, Zhang Yugui, Li Jian, Zhou Meng Feb 2020

Frequency Dispersion Mechanism Of Complex Resistivity Of Coal, Guo Yuehui, Zhang Yugui, Li Jian, Zhou Meng

Coal Geology & Exploration

In order to study the physical mechanism of frequency dispersion of complex resistivity of coal at 0-200 kHz, the amplitude-frequency and phase-frequency of complex resistivity of coal are measured under variable frequency of constant current. Using the Fourier inverse transform to convert the frequency domain data of complex resistivity of coal into time domain data; Using the Cole-Cole model, the complex resistivity dispersion data are fitted; Drawing on the electric double layer deformation hypothesis theory, the dispersion mechanism of complex resistivity of coal is studied by comparing the frequency dispersion of sandstone. The results show that in the current frequency …

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Effect Of Temperature On The Performance Of Pdc Cutters With Different Shape, Zhang Suhu, Wang Chuanliu, Dai Yongbo Feb 2020

Effect Of Temperature On The Performance Of Pdc Cutters With Different Shape, Zhang Suhu, Wang Chuanliu, Dai Yongbo

Coal Geology & Exploration

In order to explore the performance of PDC cutters at different temperatures to adapt to different brazing temperatures, and to reasonably select the shape to improve efficiency. Based on the several main parameters affecting the quality of polycrystalline diamond compacts (PDC), such as wear resistance, grinding time, stationarity and impact toughness, the performance of PDC sheets from different manufacturers and different shapes was tested. The performance of PDC before or after heating and at different temperatures was obtained. At the same time, the performance of flat sheets, micro-arcs sheets and arcs sheets was compared. The results show that with the …

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Scalable Universal Space Vector Pulse Width Modulation Scheme For Multilevel Inverters, Wei Qiao, Fa Chen, Liyan Qu Feb 2020

Scalable Universal Space Vector Pulse Width Modulation Scheme For Multilevel Inverters, Wei Qiao, Fa Chen, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

A scalable universal space vector pulse-width modulation (SVPWM) scheme for multilevel inverters is disclosed. In the disclosed SVPWM scheme, the modulation triable is quickly identified based on a coordinate transformation from an α-β coordinate system to a 120o oblique coordinate system. Then, the duty cycles and switching states of the three vertices of the modulation triangle are determined by simple algebraic computations. In a switching period, any vertex of the modulation triangle can be flexibly selected as the start point to optimize the switching sequence with flexibly adjustable duty cycle(s) for the redundant switching state(s) according to specific applications.

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Living Cell Imaging Technique Sheds Light On Molecular View Of Obesity, Usu College Of Engineering Feb 2020

Living Cell Imaging Technique Sheds Light On Molecular View Of Obesity, Usu College Of Engineering

College of Engineering News

Utah State University researchers develop probes to help improve techniques to test drugs for obesity-related conditions.

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A Qualitative Assessment Of Airline Passenger Satisfaction, Kaetlyn Blocker, Brent D. Bowen, Erin Bowen, Andrea Irish Feb 2020

A Qualitative Assessment Of Airline Passenger Satisfaction, Kaetlyn Blocker, Brent D. Bowen, Erin Bowen, Andrea Irish

Student Works

Each year, airline passengers respond to the Airline Passenger Survey providing feedback of their experiences with major domestic (U.S.) airlines. The Airline Passenger Survey analyzes responses to a varied set of questions. This specific study is limited to the single open-ended question within the survey. This question is optional, but allows an opportunity to share any issues, concerns, and/or complaints regarding their own air travel experiences. There is no limitation on the number of words submitted. Through the application of a thematic coding scheme, results show what the highest concerns of airline passengers have been the last two years.

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Cyber-Physical Security With Rf Fingerprint Classification Through Distance Measure Extensions Of Generalized Relevance Learning Vector Quantization, Trevor J. Bihl, Todd J. Paciencia, Kenneth W. Bauer Jr., Michael A. Temple Feb 2020

Cyber-Physical Security With Rf Fingerprint Classification Through Distance Measure Extensions Of Generalized Relevance Learning Vector Quantization, Trevor J. Bihl, Todd J. Paciencia, Kenneth W. Bauer Jr., Michael A. Temple

Faculty Publications

Radio frequency (RF) fingerprinting extracts fingerprint features from RF signals to protect against masquerade attacks by enabling reliable authentication of communication devices at the “serial number” level. Facilitating the reliable authentication of communication devices are machine learning (ML) algorithms which find meaningful statistical differences between measured data. The Generalized Relevance Learning Vector Quantization-Improved (GRLVQI) classifier is one ML algorithm which has shown efficacy for RF fingerprinting device discrimination. GRLVQI extends the Learning Vector Quantization (LVQ) family of “winner take all” classifiers that develop prototype vectors (PVs) which represent data. In LVQ algorithms, distances are computed between exemplars and PVs, and …

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Effects Of Intrinsic Defects And Alloying With Fe On The Half-Metallicity Of Co2Mnsi, G. G. Baez Flores, Ivan A. Zhuravlev, Kirill Belashchenko Feb 2020

Effects Of Intrinsic Defects And Alloying With Fe On The Half-Metallicity Of Co2Mnsi, G. G. Baez Flores, Ivan A. Zhuravlev, Kirill Belashchenko

Kirill Belashchenko Publications

The electronic structure and half-metallic gap of Co2MnSi in the presence of crystallographic defects, partial Fe substitution for Mn, and thermal spin fluctuations are studied using the coherent potential approximation and the disordered local moment method. In the presence of 5% Co or Mn vacancies the Fermi level shifts down to the minority-spin valence-band maximum. In contrast to NiMnSb, both types of Mn antisite defects in Co2MnSi are strongly exchange coupled to the host magnetization, and thermal spin fluctuations do not strongly affect the half-metallic gap. Partial substitution of Mn by Fe results in considerable changes in the Bloch spectral …

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Comparison Of Signaling Profiles In The Low Dose Range Following Low And High Let Radiation, Deepa M. Sridharan, Lung-Chang Chien, Francis A. Cucinotta, Janice M. Pluth Feb 2020

Comparison Of Signaling Profiles In The Low Dose Range Following Low And High Let Radiation, Deepa M. Sridharan, Lung-Chang Chien, Francis A. Cucinotta, Janice M. Pluth

Environmental & Global Health Faculty Research

During space travel astronauts will be exposed to a very low, mixed field of radiation containing different high LET particles of varying energies, over an extended period. Thus, defining how human cells respond to these complex low dose exposures is important in ascertaining risk. In the current study, we have chosen to investigate how low doses of three different ion's at various energies uniquely change the kinetics of three different phospho-proteins. A normal hTERT immortalized fibroblast cell line, 82–6, was exposed to a range of lower doses (0.05–0.5 Gy) of radiation of different qualities and energies (Si 1000 MeV/u, Si …

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Reliability Analysis Of Power Grids And Its Interdependent Infrastructures: An Interaction Graph-Based Approach, Upama Nakarmi Feb 2020

Reliability Analysis Of Power Grids And Its Interdependent Infrastructures: An Interaction Graph-Based Approach, Upama Nakarmi

USF Tampa Graduate Theses and Dissertations

Large blackouts with significant societal and economic impacts result from cascade of failures in the transmission network of power grids. Understanding and mitigating cascading failures in power grids is challenging due to the large number of components and their complex interactions, wherein, in addition to the physical topology of the system, the physics of power flow and functional dependencies among components largely affect the spatial distribution and propagation of failures. In this dissertation, data-driven interaction graphs, which help in capturing the underlying interactions and influences among the components during cascading failures, are used for capturing the non-local nature of propagation …

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Novel On-Chip Optical Modulator Designs, Mohamed Mahmoud Ibrahim Ibrahim Elsayed Feb 2020

Novel On-Chip Optical Modulator Designs, Mohamed Mahmoud Ibrahim Ibrahim Elsayed

Theses and Dissertations

The huge increments in data traffic and communication over the past few decades have pushed the conventional electronic communication systems to their physical limits in terms of data rate, bandwidth and capacity. The continuous shrinking of feature sizes, the increase in the microelectronic integrated circuits complexity, and the increasing demand for higher speeds and data rates have all stimulated seeking new technology to replace the currently present microelectronics industry rather than improving it. Photonics is one of the most likely candidates to answer this pursuit for its compatibility with the fiber optic industry, which has shown a great success in …

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