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Applications Of Surface And Subsurface Subsidence Theories To Solve Ground Control Problems, Biao Qiu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The stability of the underground mine openings largely depends on the surrounding ground conditions, such as stress concentrations, geological conditions and support intensities etc. In particular, the ground control stability associated with large movements and deformations of the strata is much more complicated and could induce much more severe safety problems. A ground control failure could endanger the coal miner's safety not only directly by roof, pillar, floor and/or rib failure, but also by ground cracks induced methane and water inundations indirectly. This study is aimed to develop comprehensive models to simulate the ground response to mining and solve the …

Three Essays On Forecasting In Nonlinear Models, Scott T. Murdoch

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nonlinear models have many applications in the economic and financial fields. The following works focus on their use for forecasting. Neural networks, in conjunction with an Affine Term Structure Model, are used to discover possible yield curve arbitrage opportunities. A G/ARCH model is employed to test and forecast the conditional variance of state-level employment growth. A Space-Time Autoregressive (STAR) model is applied to state employment growth to ensure that any measure of volatility in the series is not misdirected as employment movements between neighboring states.

Adult Characteristics Associated With Gender-Typed Toy Ratings, Rachel R. Stoiko

Graduate Theses, Dissertations, and Problem Reports (ETD)

The toys with which children play shape their development in several domains (Trawick-Smith, Russell, & Swaminathan, 2011). Exclusive or primary play with gender-typed toys may limit children's development, because toys considered appropriate for boys, girls, or both have different characteristics (Blakemore & Centers, 2005; Serbin & Connor, 1979). Especially in infancy and early childhood, children's toy play is affected by adults (parent and nonparent), who may differentially provide access to and/or reinforce play with different toys (Kane, 2006). The variability in adults' attitudes regarding the gender-appropriateness of toys is not well-understood.;The purpose of this study was to examine the relations …

Secondary Coal Seam As A Barrier To Co2 Leakage, Zainab Sahib Jawad

Graduate Theses, Dissertations, and Problem Reports (ETD)

Geologic formations, such as unmineable or depleted coal seams, are considered to be potential reservoirs for CO2 storage. Coal seams are naturally fractured reservoirs which consist of primary and secondary cleat networks. During production, coalbed methane (CBM) is desorbed from the coal surface and flows through the cleat network. When carbon dioxide (CO2) is injected into a coal seam, large amount of the injected CO2 is sorbed on the coal surface due to the greater affinity of CO2 towards coal than methane. This provides two advantages: potential CO 2 storage and enhanced coalbed methane recovery. Several pilot studies have been …

Reservoir Simulation For Production Of Methane From Gas Hydrate Reservoirs Using Carbon Dioxide/Carbon Dioxide+Nitrogen By Hydrateressim., Nagasree Garapati

Graduate Theses, Dissertations, and Problem Reports (ETD)

Natural gas hydrate reservoirs are likely to contain more carbon than in all other fossil fuel reserves combined. Different techniques currently being proposed for production of CH4 from hydrate deposits include depressurization, thermal stimulation and inhibitor injection. These processes involve the dissociation of hydrate and the release of significant volumes of water, which may cause geomechanical stress on the reservoir leading to subsidence. A series of experimental studies over the decade reviewed the feasibility of using CO2/CO2+N2 gas mixtures to recover CH4 gas from the hydrates, which serves the dual purpose of CO2 sequestration and production of CH4 while maintaining …

Comparing U.S. And International Medical Graduates' Treatment Of Chronic Diseases: Utilization Of Psychosocial Interventions., Susan E. Jarquin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Chronic disease care places significant pressure on healthcare provider resources, often requiring the hiring of physicians trained abroad to meet these demands. International medical graduates are on trend to become the primary suppliers of chronic disease care in the U.S. Consequently, there is a need to assess how physicians trained abroad care for patients with chronic diseases. The purpose of this exploratory survey study was to determine whether international and U.S. medical graduates differ in their use of three specific psychosocial interventions when caring for patients suffering from chronic diseases. Medical residents in U.S. allopathic family medicine and internal medicine …

How Teachers' Perceptions Impact Their Implementation Of Response To Intervention., Mary F. Kakascik

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examines the impact of effective instructional strategies, evidence-based curricula, and professional collaboration upon implementing a Response to Intervention program. Qualitative research methods, including interviews and lesson plan document analysis comprise the research data from seven teachers and one administrator. This study is designed to enrich the existing body of descriptive data on teacher perceptions, especially with regard to their professional practice, expertise, and judgment within a Response to Intervention system. The results of this study provide insight into teachers’ perspectives after experiencing this educational transformation. The research provides professional knowledge and practical experience that extends beyond the general …

Degradation Studies Of Flexible Optoelectronic Device Electrodes, Theodros S. Bejitual

Graduate Theses, Dissertations, and Problem Reports (ETD)

Flexible transparent electrodes offer significant advantages, such as low cost, large area, light weight, conformability, robustness, and ease of roll-to-roll manufacturing and processing. They are routinely used as anodes in organic light emitting diodes, liquid crystal displays, touch panels, solar cells, solid state lightings, energy harvesting, and biomedical applications to name a few examples. However, the electromechanical and corrosion issues involved when the device is stressed and/or in contact with acid containing components both during manufacturing and/or in service conditions have to be investigated in order to improve, and predict reliability.;The primary objective of this research is to investigate the …

Analysis Of Gps Abnormal Conditions Within Fault Tolerant Control Laws, Gahssan Al-Sinbol

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Global Position System (GPS) is a critical element for the functionality of autonomous flying vehicles. The GPS operation at normal and abnormal conditions directly impacts the trajectory tracking performance of the autonomous Unmanned Aerial Vehicles (UAVs) controllers. The effects of GPS parameter variation must be well understood and user-friendly computational tools must be developed to facilitate the design and evaluation of fault tolerant control laws.;This thesis presents the development of a simplified GPS error model in Matlab/Simulink and its use performing a sensitivity analysis of GPS parameters effect under system normal and abnormal operation on different UAV trajectory tracking …

Analysis Of Production Data From Marcellus Shale Horizontal Wells In Wv, Mohamed N. El Sgher

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years, the interest in unconventional reservoirs has increased all over the world. The unconventional gas reservoir is a term commonly used to refer to a low permeability reservoir that produces mainly dry natural gas and is not able to produce an economic flow rate without stimulation treatments. The best way to improve the production is by a horizontal well with multiple hydraulic fractures. Hydraulic fracturing is a stimulation practice to improve the permeability in order to obtain commercial production. Horizontal wells with multiple hydraulic fracture treatments have proven to be an effective method for development of unconventional reservoirs.;The …

Numerical Modeling Of Carbon Dioxide Injection At A Pilot Sequestration Site, Benjamin David Bowes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over the past several years, lessons learned from various sequestration sites have identified deep, unmineable coal seams as favorable and profitable reservoirs for commercial carbon dioxide (CO2) sequestration and long-term CO2 storage. Long-term consequences, however, have not been completely identified and understood. In order to assess the aptitude of such deep unmineable coal seams for a possible commercial sequestration site, a reservoir modeling study was performed at an ongoing Pump Canyon, NM sequestration site located in the coalbed methane (CBM) fairway region of the well-established San Juan basin. The demonstration at the Pump Canyon pilot area is a part of …

Novel Techniques For Automated Dental Identification, Nourdin Al-Sherif

Graduate Theses, Dissertations, and Problem Reports (ETD)

Automated dental identification is one of the best candidates for postmortem identification. With the large number of victims encountered in mass disasters, automating the process of postmortem identification is receiving an increased attention. This dissertation introduces new approaches for different stages of Automated Dental Identification system: These stages include segmentations, classification, labeling, and matching:;We modified the seam carving technique to adapt the problem of segmenting dental image records into individual teeth. We propose a two-stage teeth segmentation approach for segmenting the dental images. In the first stage, the teeth images are preprocessed by a two-step thresholding technique, which starts with …

Finite Element Modeling Of Geosynthetic Soil Reinforcement Over Shallow Buried Pipes, Andrew L. Dietz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Buried pipes serve an important role in many engineering applications and are vital to the infrastructure of our everyday life. It is imperative that, once in place, these pipes last as long as possible to avoid failure and costly replacement. Advancements in technology and understanding of soil-pipe interactions can extend the service life of these pipes. In this study, a new approach is taken to increase buried pipe performance.;The purpose of this research work is to explore the potential improvements of pipe performance under surface loading by using a geosynthetic reinforcement in the soil layer above a buried pipe. Various …

Evaluation Of The Osha Local Emphasis Program (Lep) For Logging In West Virginia, Olukemi O. Alonge

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research aimed at an improved method for evaluating the West Virginia Occupational Safety and Health Administration's Local Emphasis Program (WV OSHA LEP) for Logging in West Virginia. The LEP currently uses for assessment: loggers' training, inspections at logging sites, number of fatalities and 75% of loggers' participation to determine the program's effectiveness annually. The research here proposes the use of a larger data capture to evaluate the impact of the LEP on loggers' safety.;A heuristic method using the Iceberg model of safety was applied to assess loggers' safety based on the desired safety outcome measures outlined in the OSHA …

Phase Transformations Of Microcrystalline Cellulose Under Ball-Milling And Hydrothermal Treatment, Sai Kishore Pyapalli

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis, experimental results and their analysis are presented on the phase transformations of microcrystalline cellulose (MCC) under two different treatments. First, MCC was subjected to ball milling in air for different times tBMi = 5, 10, 15, 30, 45, 60 and 120 minutes. Second, phase transformation of MCC under hydrothermal treatment (HTT) in distilled water using an autoclave was investigated by varying the pressure P, temperature T for different time tau. Both of the post treated samples were analyzed by X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy, surface area measurements, Scanning Electron Microscopy (SEM) and Thermo-gravimetric Analysis …

Novel 3d Ultrasound Elastography Techniques For In Vivo Breast Tumor Imaging And Nonlinear Characterization, Ahmed A. Hameed Sayed

Graduate Theses, Dissertations, and Problem Reports (ETD)

Breast cancer comprises about 29% of all types of cancer in women worldwide. This type of cancer caused what is equivalent to 14% of all female deaths due to cancer. Nowadays, tissue biopsy is routinely performed, although about 80% of the performed biopsies yield a benign result. Biopsy is considered the most costly part of breast cancer examination and invasive in nature. To reduce unnecessary biopsy procedures and achieve early diagnosis, ultrasound elastography was proposed.;In this research, tissue displacement fields were estimated using ultrasound waves, and used to infer the elastic properties of tissues. Ultrasound radiofrequency data acquired at consecutive …

Investigation Of Truckload Prices In The U.S: Exploratory Analysis, Forecast Methods, And The Influences Of Unemployment On Freight Prices, Alex M. Sanchez

Graduate Theses, Dissertations, and Problem Reports (ETD)

Truckload (TL) pricing is a major factor that influences the manufacturing and retail costs of products. In the U.S., trucks accounts for more than 90% of freight shipped based on value, and it is expected to grow in the following years. TL price setting is a very complex task for logistic companies as it depends on a number of factors including the logistics carriers' business strategies and other social and economic variables. Understanding TL patterns across the U.S. is important not only for logistic companies, but also for policy makers. TL prices are commonly provided on a dollar per mile …

Modeling Of High Pressure Confined Inflatable Structures, Jerry C. Wong

Graduate Theses, Dissertations, and Problem Reports (ETD)

Safety of transportation tunnels is a top priority among transportation agencies and public administrators and a very important aspect in the daily operation of a tunnel system. However, it is always a challenge to create and integrate protection systems in existing tunnels to prevent or at least mitigate the occurrence of hazardous events such as spread of smoke or noxious fumes, flooding, among others. Typically there two ways for preventing or mitigating the occurrence of hazardous events: one is the implementation of permanent solutions and, the second one, is the use of temporary solutions. Permanent solutions usually have relatively high …

The Health Sciences And Technology Academy (Hsta): A Case Study Of The Community Impact Of A 9th Through 12th Grade After School Pipeline Program, Catherine Morton-Mcswain

Graduate Theses, Dissertations, and Problem Reports (ETD)

This is a qualitative case study designed to examine the viewpoints community members have about the after-school Health Sciences Technology Academy (HSTA) pipeline program for students in grades nine through twelve. The program is designed to foster success and improve the college going rate of under-represented students or what one colleague described as "kids on the bubble." There is little existing literature that examines community impact from the outside or gives voice to community members.

Health Sciences and Technology Academy (HSTA) has been in existence for 19 years in 26 of the 55 counties in West Virginia. It requires a …

Coupling Numerical Simulation And Pattern Recognition To Model Production And Evaluate Carbon Dioxide Injection In Shale Gas Reservoir, Amirmasoud Kalantari-Dahaghi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Massive multi-cluster, multi-stage hydraulic fractures have significantly increased the complexity of the flow behavior in shale. This has translated into multiple challenges in the modeling of production from shale wells.

Most commonly used numerical techniques for modeling production from shale wells are Explicit Hydraulic Fracture (EHF) and Stimulated Reservoir Volume (SRV). Model setup for the EHF technique is long and laborious and its implementation is computationally expensive, such that it becomes impractical to model beyond a single pad. On the other hand, identifying the extent and conductivity of SRV is a challenging proposition. SRV technique is commonly used to simplify …

Forensic And Toxicological Applications Of Franz Diffusion Cells Assessed By Gas Chromatograhy Mass Spectrometry And Ion Mobility Spectrometry., Jordan Wade Moran

Graduate Theses, Dissertations, and Problem Reports (ETD)

The first portion of this work evaluated the efficacy of ion mobility spectrometry (IMS) as a tool for determining remediation success at clandestine methamphetamine laboratory sites. Specifically, limits of detection (LOD), limits of quantitation (LOQ), and matrix effects were investigated as relevant to typical remediation sites and situations. The recoveries of pseudoephedrine and methamphetamine from a range of various surfaces likely to be found in a clandestine laboratory were examined. Portable IMS instruments with thermal desorption were found to be a reliable tool for evaluating the degree of remediation if sufficient procedural and instrumental controls are put into place. In …

Characterization And Application Of Self-Assembled Nano-Materials For Fluid Steering And Separation In Microfluidics, Xingwei Wu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Aqueous phospholipid preparations comprised of 1,2-dimyristoyl- sn-glycero-3- phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) are prevalent materials for biological characterization. The viscosity behavior of DMPC/DHPC was characterized as a function of q value (q= [DMPC]/[DHPC] ), hydration as well as temperature firstly on bench-top and then in microfluidic chip. The rheology of 20% phospholipid preparations of [DMPC]/[DHPC] = 2.5 reveals that, under conditions utilized for fluid steering, the materials are shear-thinning power-law fluids with a power-law index ranging from 0.30 through 0.90. Phospholipid preparations are utilized to steer fluids in microfluidic chips and support hydrodynamic delivery of sample across a double T …

Connectivity And Spanning Trees Of Graphs, Xiaofeng Gu

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation focuses on connectivity, edge connectivity and edge-disjoint spanning trees in graphs and hypergraphs from the following aspects.;1. Eigenvalue aspect. Let lambda2(G) and tau( G) denote the second largest eigenvalue and the maximum number of edge-disjoint spanning trees of a graph G, respectively. Motivated by a question of Seymour on the relationship between eigenvalues of a graph G and bounds of tau(G), Cioaba and Wong conjectured that for any integers d, k ≥ 2 and a d-regular graph G, if lambda 2(G)) < d -- 2k-1d+1 , then tau(G) ≥ k. They proved the conjecture for k = 2, 3, and presented evidence for the cases when k ≥ 4. We propose a more general conjecture that for a graph G with minimum degree delta ≥ 2 k ≥ 4, if lambda2(G) < delta -- 2k-1d+1 then tau(G) ≥ k. We prove the conjecture for k = 2, 3 and provide partial results for k ≥ 4. We also prove that for a graph G with minimum degree delta ≥ k ≥ 2, if lambda2( G) < delta -- 2k-1d +1 , then the edge connectivity is at least k. As corollaries, we investigate the Laplacian and signless Laplacian eigenvalue conditions on tau(G) and edge connectivity.;2. Network reliability aspect. With graphs considered as natural models for many network design problems, edge connectivity kappa'(G) and maximum number of edge-disjoint spanning trees tau(G) of a graph G have been used as measures for reliability and strength in communication networks modeled as graph G. Let kappa'(G) = max{lcub}kappa'(H) : H is a subgraph of G{rcub}. We present: (i) For each integer k > 0, a characterization for graphs G with the property that kappa'(G) ≤ k but for any additional …

Network Dynamics, Synchronization, And Self-Propelled Particles In Chemical Systems, Hua Ke

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neural networks are a class of biological networks of great importance. They are a key component of the central nervous system that coordinates body functions. The exploration of the detailed mechanism of biological neural networks remains extremely active. Inspired by the structure of biological neural networks, artificial neural networks have been designed to solve a variety of problems in pattern recognition, prediction, optimization and control. However, few studies have been reported that explore the dynamics of biological neural networks using chemical systems. As part of this thesis, an experimentally trainable network based on the photosensitive Belousov-Zhabotinsky reaction is developed, where …

Intelligent Web Crawling Using Semantic Signatures, Lingaiah Choudary Pinnamaneni

Graduate Theses, Dissertations, and Problem Reports (ETD)

The quantity of test that is added to the web in the digital form continues to grow and the quest for tools that can process this huge amount of data to retrieve the data of our interest is an ongoing process. Moreover, observing these large volumes of data over a period of time is a tedious task for any human being. Text mining is very helpful in performing these kinds of tasks. Text mining is a process of observing patterns in the text data using sophisticated statistical measures both quantitatively and qualitatively. Using these text mining techniques and the power …

Attitude Of Saudi Female Math Teachers Toward Integrating E-Learning In Teaching Math At High Schools In Saudi Arabia, Aishah M. Albalawi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Leaders in government and education have launched an extensive program to reform general education in Saudi Arabia. This initiative was designed to achieve many goals with a major emphasis being the enhancement of the Saudi curriculum to take advantage of the use of technology to improve education. A goal of this project was for e-learning to be a part of public education in an attempt to improve student learning and to make education accessible to all citizens.;This study was designed to examine high school female math teachers' attitudes toward the use of e-learning in teaching mathematics in selected high schools …

Evaluation Of The Effects Of Aggregate Gradation And Compaction Effort On The Voids In Mineral Aggregate In Asphalt Concrete, Logan Bessette

Graduate Theses, Dissertations, and Problem Reports (ETD)

Asphalt concrete should resist short-term rutting, provide resistance to thermal cracking, and maintain structural integrity through the design life of the structure. Balancing these factors is achieved by ensuring adequate asphalt binder in a strong aggregate structure. The design asphalt content is decreased by applying additional compaction effort in the form of increased gyrations in the Superpave Gyrator Compactor. The mixes that undergo increased compaction effort present decreased fatigue life, although they resist short-term rutting. Mixes that undergo less compaction effort contain more binder and have long fatigue lives, although they are susceptible to rutting.;Two hypotheses were tested to determine …

Effects Of Stereotype Threat On Adolescents' Math And Visual-Spatial Performance., Lisa M. Didonato

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent research suggests that the gender gap in math performance is closing (Else-Quest, Hyde, & Linn, 2010; Hyde, Lindberg, Linn, Ellis, & Williams, 2008). However, negative stereotypes about girls’ math abilities are still widely held (Bhanot & Jovanovic, 2005; Bleeker & Jacobs, 2004). The gender gap in visual-spatial skills, or the ability to reason about and manipulate mental pictures, still exists in that boys outperform girls on visual-spatial tasks. The current study drew from literature on stereotype threat (i.e., the risk of confirming negative stereotypes about a specific group; Steele, 1997) to investigate the impact of negative math stereotypes on …

Decentralized Synergetic Control Of Power Systems, Taoridi Ademoye

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this dissertation is to design decentralized controllers to enhance the transient stability of power systems. Due to the nonlinearities and complexities of the system, nonlinear control design techniques are required to improve its dynamic performance. In this dissertation a synergetic control technique is being proposed to design supplementary controller that is added to the exciter of the generation unit of the system. Although this method has been previously applied to a Single Infinite Machine Bus (SMIB) system with high degree of success, it has not been employed to systems with multi machine. Also, the method has good …

Impact Of Stress-Field Changes Induced By Hydraulic Fracturing On Subsurface Fault Stability, Qian Gao

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hydraulic fracturing is essential for economically producing hydrocarbons from shale reservoirs, and thus has been extensively used in completion of shale gas wells. However, fracturing formations can change in-situ stresses in the surrounding areas. There are concerns that hydraulic fracturing may potentially reactivate the subsurface faults nearby the treatment wells. The reactivated faults could cause many problems, such as early aborting/failure of fracturing treatment, fluid leakage along the fault and even seismicity events.;3D numerical models are developed based on finite element method. The comparison between analytical and numerical solutions indicates an excellent agreement has been achieved, which certificates the applicability …