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Graduate Theses, Dissertations, and Problem Reports

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Full-Text Articles in Engineering

Investigation Of Combustion Characteristics Of A Heavy-Duty Diesel Engine Retrofitted To Natural Gas Spark Ignition Operation, Jinlong Liu Jan 2018

Investigation Of Combustion Characteristics Of A Heavy-Duty Diesel Engine Retrofitted To Natural Gas Spark Ignition Operation, Jinlong Liu

Graduate Theses, Dissertations, and Problem Reports

The conversion of existing diesel engines to natural-gas spark ignition operation by adding a gas injector in the intake manifold for fuel delivery and replacing the diesel fuel injector with a spark plug to initiate and control the combustion process can reduce U.S. dependence on petroleum imports and curtail engine-out emissions. As the conventional diesel combustion chamber (i.e., flat head and bowl-in-piston) creates high turbulence, the engine can operate leaner, which would increase its efficiency and reduce emissions. However, natural gas combustion in such retrofitted engines presents differences compared to that in conventional spark ignited engines. Subsequently, the main goal …


The Determination Of The Concrete Tensile Creep At Early Age Using The Ring Test, Tadamon Mohammed Jan 2018

The Determination Of The Concrete Tensile Creep At Early Age Using The Ring Test, Tadamon Mohammed

Graduate Theses, Dissertations, and Problem Reports

In this study, the modified double power law (MDPL) model is used to determine the tensile creep of concrete at an early age based on the ASTM C1581 restrained shrinkage ring test. Three concrete mixes using Ordinary Portland Cement (OPC) were tested. The three concrete mixes were cast, and each underwent the ring tests up to cracking. Mechanical properties of concrete at the age of 1, 3, 7, 14, and 28 days were tested to find the compressive strength, tensile strength and Young’s Modulus of concrete. The strength tests results were obtained from both 4x8 inch and 6x12 inch cylinders. …


Remotely Sensed Hydroclimatic Variability For Water Security In An Agricultural Basin, Ashish Kondal Jan 2018

Remotely Sensed Hydroclimatic Variability For Water Security In An Agricultural Basin, Ashish Kondal

Graduate Theses, Dissertations, and Problem Reports

The Indus Basin has supported agricultural practices since the Harappan civilization (3000-1500 BC). Abundance of water has always supported agriculture in the region and built the Indus Basin as one of the major agriculture based economies of the world. The obvious dependency of agriculture on weather and the vagaries of climate emphasizes the necessity of a comprehensive hydro-climate study of the region. The role of climate change in the Indus Basin has always been a contentious issue. Groundwater depletion is evident in the region, and its steady and alarmingly declining rate has brought concerns for the future of agriculture in …


Tire-Derived Geo-Cylinders And Polymer Products For Enhancing The Properties Of Base/Sub Base Materials In Pavement Systems, Justin Scott Smith Jan 2018

Tire-Derived Geo-Cylinders And Polymer Products For Enhancing The Properties Of Base/Sub Base Materials In Pavement Systems, Justin Scott Smith

Graduate Theses, Dissertations, and Problem Reports

As a critical part of the transportation network, pavements offer a safe means for vehicular traffic. Pavements are subjected to many forms of stress during their service life, and they are susceptible to environment related cracking and failures. Failures can be attributed to poor subgrade, freeze-thaw variations, and fatigue under repetitive axle loadings. Reinforcement products such as tire-derived geo-cylinders (TDGC) which make-up mechanical concrete and geo-polymers have been utilized in civil engineering practice, and this research aims to understand the potential life of tested pavement system components set at displacement limitations when reinforced with TDGCs and geo-polymers from exposure to …


Design And Optimization Of A 1 Kw Stirling Engine, Garrett Tyler Rinker Jan 2018

Design And Optimization Of A 1 Kw Stirling Engine, Garrett Tyler Rinker

Graduate Theses, Dissertations, and Problem Reports

Stirling engines are often overlooked as a means of energy conversion, though its versatility offers many advantages. Since it is an external combustion engine, it can be supplied with heat through the combustion of a variety of fuels. Its maintenance- and degradation-free aspects, as well as its excellent turn down ratio, make it a suitable candidate for applications such as remote power generation, combined heat and power (CHP), cryogenics, solar power, and even space exploration. The continual advancement of additive manufacturing (AM) offers opportunity to potentially further improve the already efficient Stirling cycle. This dissertation presents the design and optimization …


Study On Electrolyte-Gated Graphene Nanoelectronic Biosensors For Biomarker Detection, Jianbo Sun Jan 2018

Study On Electrolyte-Gated Graphene Nanoelectronic Biosensors For Biomarker Detection, Jianbo Sun

Graduate Theses, Dissertations, and Problem Reports

Biosensors are called upon to provide valuable benefits for human society in vital fields such as disease diagnosis, food inspection, environment monitoring, etc. Among the various biosensor architectures, the field effect transistor (FET) biosensors are promising as the next generation nanoelectronic biosensors, particularly attractive for point-of-care biomedical applications. The FET biosensors typically operate by measuring the conductance change of the semiconducting channel induced by the adsorption of the target biomolecules on it. The superior properties of graphene, including the unique electronic characteristics, facile functionalization and good biocompatibility, etc., make it an ideal building block for the FET biosensors. In this …


Shale Characterization And Size-Effect Study Using Scanning Electron Microscopy And X-Ray Diffraction, Debashis Das Jan 2018

Shale Characterization And Size-Effect Study Using Scanning Electron Microscopy And X-Ray Diffraction, Debashis Das

Graduate Theses, Dissertations, and Problem Reports

Ground failure is a major contributor of the total fatalities in underground mines in the US. Underground coal mines in the Northern Appalachian region have weak roof rock mainly composed of shale and sandstone. Characterization of shale is indispensable for developing an effective ground control plan. However, this has not been done extensively. This thesis attempts to address this issue. It investigates the variation in mechanical properties of shale with variation in size. In addition, an attempt has been made to relate the strength of shale with its petrographic parameters. X-ray diffraction technique was used to estimate the compositional parameters …


Resilience Modeling Of Surface Transportation System In Mixed Traffic Environment, Shofiq Ahmed Jan 2018

Resilience Modeling Of Surface Transportation System In Mixed Traffic Environment, Shofiq Ahmed

Graduate Theses, Dissertations, and Problem Reports

Large-scale natural disasters challenge the resilience of surface transportation system. The objective of this research was to develop a resilience model of surface transportation system in mixed-traffic environment considering varying Connected and Automated Vehicle (CAV) penetration scenarios. As deployment of CAVs are expected to improve traffic operations, a resilience model was developed in this research to evaluate the resilience performance of a transportation system with several CAV penetration levels (0%, 25%, 50%, 75% and 100%) for a given budget and recovery time. The proposed resilience quantification model was applied on a roadway network considering several disaster scenarios. The network capacity …


Application Of Machine Learning On Fracture Interference, Dennis Wayne Chamberlain Jr. Jan 2018

Application Of Machine Learning On Fracture Interference, Dennis Wayne Chamberlain Jr.

Graduate Theses, Dissertations, and Problem Reports

A method has been developed that locates and determines well-to-well hydraulic fracture interference (frac-hit) in shale plays using hard data. This method uses Artificial Neural Networks (ANN) with designated parameters and target outputs in conjunction with graphs of gas flowrate, tubing pressure, and cumulative gas prediction. The method was created to address the significant increase in frac-hit occurrences due to the infill wells being completed in shale plays. The production data of the well is first cleaned to eliminate outliers in the initial timeframe of the well and periods of no production so that the ANN model can be accurately …


Automated Cleaning Of Identity Label Noise In A Large-Scale Face Dataset Using A Face Image Quality Control, Mohamad Al Jazaery Jan 2018

Automated Cleaning Of Identity Label Noise In A Large-Scale Face Dataset Using A Face Image Quality Control, Mohamad Al Jazaery

Graduate Theses, Dissertations, and Problem Reports

For face recognition, some very large-scale datasets are publicly available in recent years which are usually collected from the internet using search engines, and thus have many faces with wrong identity labels (outliers). Additionally, the face images in these datasets have different qualities. Since the low quality face images are hard to identify, current automated identity label cleaning methods are not able to detect the identity label error in the low quality faces. Therefore, we propose a novel approach for cleaning the identity label error more low quality faces. Our face identity labels cleaned by our method can train better …


Development Of Oxide-Dispersion-Strengthened Nickel-Based Super Alloy Powders For Additive Manufacturing, Sizhe Huang Jan 2018

Development Of Oxide-Dispersion-Strengthened Nickel-Based Super Alloy Powders For Additive Manufacturing, Sizhe Huang

Graduate Theses, Dissertations, and Problem Reports

Oxide-Dispersion-Strengthened (ODS) Nickel-Based superalloy has been drawn a huge attention and developed with good oxidation resistance, corrosion resistance and high creep strength. It has been considered as critical materials for Additive Manufacturing (AM). The quality and the efficiency of fabrication methods of ODS limits the performance of itself on AM. The development of new type of ODS, new methodologies and evaluation techniques are required if the enhanced quality of ODS and enhanced efficiency of fabrication are to be achieved. Of the current fabrication techniques for AM, Gas Atomization (GA) is widely used since they can generate spherical powders with high …


On Designing An Ecg-Based Intelligent System: Utilizing The Heart’S Electrical Activity To Recognize Humans And Detect Arrhythmia, Sara Saeed Abdeldayem Jan 2018

On Designing An Ecg-Based Intelligent System: Utilizing The Heart’S Electrical Activity To Recognize Humans And Detect Arrhythmia, Sara Saeed Abdeldayem

Graduate Theses, Dissertations, and Problem Reports

The electrocardiogram (ECG) signal is the bioelectrical signal that reflects the heart's activity. It has been extensively used as a diagnostic tool since it holds information about the cardiac health condition. However, recent researches have shown that it exhibits an inter-subject variability property. Therefore, it can be used as a biometric-based modality for either identification or verification purposes. Nevertheless, some of the challenges are faced while employing such a signal. For instance, ECG signal is prone to noise, accordingly, noise filters should be designed to remove the noise while keeping the signal properties. Moreover, factors such as medications, health condition, …


Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney Jan 2018

Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney

Graduate Theses, Dissertations, and Problem Reports

Decentralized power generation is a research area of interest due to possible improvements in electrical generation efficiency and grid resilience. Two-stroke engines are simple, inexpensive, power dense systems that could serve as the prime-movers for combined heat and power (CHP) systems. In addition, such systems could be fueled on natural gas (NG) that is readily available to serve as a reliable fuel source in most households. However, most two-stroke engines are inefficient and produce excessive emissions. This research focused on methods to simultaneously improve engine efficiency and decrease emissions from a 34 cc air-cooled, two-stroke engine retrofitted to operate on …


Plasmon-Enhanced Optical Sensing By Engineering Metallic Nanostructures, Peng Zheng Jan 2018

Plasmon-Enhanced Optical Sensing By Engineering Metallic Nanostructures, Peng Zheng

Graduate Theses, Dissertations, and Problem Reports

The world’s booming population projected to reach 10 billion by 2050 causes enormous stresses on environmental safety, food supply, and healthcare, which in return threatens human civilizations. One of the most promising solutions lies at innovating point-of-care (POC) sensing technologies to conduct detection of environmental hazards, monitoring of food safety, and early diagnosis of diseases in a timely and accurate manner. The discovery of surface-enhanced spectroscopy in the 1970s has significantly stimulated research on light-matter interaction which gives rise to enhanced optical phenomena such as surface-enhanced Raman scattering (SERS), plasmon-enhanced fluorescence (PEF), and particularly, they have found enormous applications in …


Differentiating Human Populations Based On K-Mer Classification Of Hand Bacteria, Thrisha Doppala Jan 2018

Differentiating Human Populations Based On K-Mer Classification Of Hand Bacteria, Thrisha Doppala

Graduate Theses, Dissertations, and Problem Reports

Bacterial communities found in and on the human body are not only used in studying human health conditions but are also effective in differentiating individuals due to their distinct profiles. Human palm regions harbor relatively more diverse bacterial communities and are indicative of population groups, life styles, geographic locations, age groups and health conditions. Sequences extracted from hypervariable region V3 of the 16S rRNA bacterial gene of hand bacterial samples from 9 different population groups were classified into Operational Taxonomic Units (OTU) with GreenGenes reference taxonomy using RDP (Ribosomal Database Project) classifier. Frequencies of identified OTUs were used to study …


The Nakahara Effect And Its Influence On Solution-Based 3d Printed Films, Daryl Kwakye-Ackah Jan 2018

The Nakahara Effect And Its Influence On Solution-Based 3d Printed Films, Daryl Kwakye-Ackah

Graduate Theses, Dissertations, and Problem Reports

Motivated by the Nakahara Effect, the influence of altering printing parameters on fragmentation mechanism(s) of directly written titanium dioxide(TiO2) films is investigated. The Nakahara effect states that a long lasting memory can be introduced into a colloidal system prior to drying, affecting the type of crack pattern formed due to externally applied forces. TiO2 has important applications due to its interesting semiconducting properties, tunable band gap, photocatalytic properties, biocompatibility, and relative abundance. This is the reason it is used in this project as a model printing ink system.

In this research, two deposition methods (i.e. direct-ink writing …


Using Artificial Intelligence And Machine Learning To Develop Synthetic Well Logs, Marwan Mohammed Alnuaimi Jan 2018

Using Artificial Intelligence And Machine Learning To Develop Synthetic Well Logs, Marwan Mohammed Alnuaimi

Graduate Theses, Dissertations, and Problem Reports

There has been an increase in the need for energy in the recent past. Oil and gas stand as the source of energy that are widely used. The oil and gas reservoirs are targeted for the purposes of field development. The conventional methods of reservoir characteristics require computing techniques that are unique and complex, some of which are labor and time intensive. Mohaghegh argues that all efforts must be tried and made possible to apply Petroleum Data analytics in production and management of reservoir so as to earn a maximum return (Mohaghegh, Shale Analytics, 2017). Different methodologies have been applied …


Design And Development Of Test Rigs To Experimentally Investigate Flow Loss And Heat Transfer In A Stirling Engine Heater Head, Pawan K. Yadav Jan 2018

Design And Development Of Test Rigs To Experimentally Investigate Flow Loss And Heat Transfer In A Stirling Engine Heater Head, Pawan K. Yadav

Graduate Theses, Dissertations, and Problem Reports

The Stirling engines are attractive alternative for combined heat and power (CHP) systems, especially for high efficiency power generation using different heat sources. The hot side heat exchanger or heater head (HH) is one of the indispensable components of Stirling engines which transfers the heat from outside of the system into the working fluid. For development of a low cost, highly efficient and reliable CHP system, a novel HH has been designed and additively manufactured from Inconel 625. For the investigation of flow loss and heat transfer through this Stirling engine heater head, two benchtop test rigs were designed, developed, …


Optimizing Indoor Location Based Tracking Through Proper Filter Selection And Wireless Sensor Network Design, Matthew R. Bergman Jan 2018

Optimizing Indoor Location Based Tracking Through Proper Filter Selection And Wireless Sensor Network Design, Matthew R. Bergman

Graduate Theses, Dissertations, and Problem Reports

Indoor positioning system (IPS) is a topic that is coming up more and more for various reasons, such as allowing companies to track important objects using radio frequency identification (RFID) and employees with Bluetooth devices inside a facility. Geofencing is one of the biggest topics with IPS and is meant to limit access to a network in specified areas. Devices that incorporate indoor tracking are not initially precise when objects and employees are on the move. This movement requires devices to have a reliable filter for noise and package lose. For this paper, the comparison between extended Kalman filters and …


A Lab-Based Study Of N95 Ffrs Against Cigarette Smoke Under Varying Concentrations And Sealing Conditions, Jacob Davis Jan 2018

A Lab-Based Study Of N95 Ffrs Against Cigarette Smoke Under Varying Concentrations And Sealing Conditions, Jacob Davis

Graduate Theses, Dissertations, and Problem Reports

Respirators are a common form of protection when working in environments where workers are exposed to harmful agents. One exposure that has not been rigorously tested is cigarette smoke. Air sampling was conducted to test the effectiveness of four different respirators N95 Respirators for various concentrations of cigarette smoke and seal conditions and for different respirators. The Moldex 2200, Moldex 2300 (exhalation valve), Gerson 1730, and 3M 8210V (Exhalation valve) were used for testing. The set concentrations were 100,000: 200,000: and 400,000 cm3 with an error allowance of 20% for each concentration. Different flow rates (15, 30, 50, and 85 …


Comparison Of Emissions Measurement Between A Sensor-Based Compact Emissions Meter And A Standard Pems, Jordan Matthew Leatherman Jan 2018

Comparison Of Emissions Measurement Between A Sensor-Based Compact Emissions Meter And A Standard Pems, Jordan Matthew Leatherman

Graduate Theses, Dissertations, and Problem Reports

The emissions produced by diesel engines are detrimental to human health, and the environment. To reduce these harmful emissions, engine manufacturers have used exhaust after treatment systems. The main objective of these after-treatment systems is to reduce exhaust emissions with minimal impact on an engines performance. The increase in emission regulations resulted in the need for a portable device to measure emissions. Portable emissions measurement systems (PEMS) are used to ensure engines comply with regulations in the real world. Although these systems are portable and can be installed on a vehicle they are bulky, expensive and time consuming to install. …


Parametric Study Of Coal Liberation Behavior Using Silica Grinding Media, Adewale Wasiu Adeniji Jan 2018

Parametric Study Of Coal Liberation Behavior Using Silica Grinding Media, Adewale Wasiu Adeniji

Graduate Theses, Dissertations, and Problem Reports

This study evaluates the coal liberation behavior using silica as the grinding media by assessing the effects of four operating factors including nominal feed size, media size, shaft speed and grinding time, each of three levels on two response variables, the product P80 and the specific energy. The coal material used in this study was mixed-phase particles commonly referred to as middlings, sampled from dense medium circuit at the Leatherwood preparation plant in Kentucky. One-third fractional factorial design of resolution III was implemented. Since silica was obtained in three standard size ranges as per manufacturer’s design, media size was …


Instrumentation And Inertial Navigation Systems Design For Tensegrity Robot Implementations, Scott Edward Harper Jan 2018

Instrumentation And Inertial Navigation Systems Design For Tensegrity Robot Implementations, Scott Edward Harper

Graduate Theses, Dissertations, and Problem Reports

One of the major challenges faced when developing missions for the exploration of planetary bodies is the risk these terrains pose on the science platform when using a traditional lander or wheeled rover. One means of developing platforms to traverse these harsh terrains is to utilize mobility systems comprised of tensegrity structures. These structures have the capacity to distribute loads across a network of axially loaded members such that they can be constructed in a very lightweight manner and morph their geometries when required. In literature, there has been significant progress in simulated environments to utilize tensegrity structures as mobility …


An Experimental Investigation Of The Cooling System For A Free Piston Stirling Engine, Akshay Milind Gupte Jan 2018

An Experimental Investigation Of The Cooling System For A Free Piston Stirling Engine, Akshay Milind Gupte

Graduate Theses, Dissertations, and Problem Reports

Free-Piston Stirling Engine (FPSE) has been identified as a good candidate for combined heat and power application (CHP). FPSE being highly efficient and environmentally friendly promises to facilitate the increasing demand in waste heat energy recovery systems. FPSE system consists of three important components: (1) hot side heat exchanger; (2) regenerator; and (3) cold side heat exchanger. The cold side heat exchanger is a crucial part as it enables to maintain an optimal temperature of the working fluid by rejecting heat.

This research contributes to the design of heat exchanger test rig and experimental measurement of cooling heat exchanger. The …


Analysis Of The Production Data From Marcellus Shale Wells, Amanda Parrish Jan 2017

Analysis Of The Production Data From Marcellus Shale Wells, Amanda Parrish

Graduate Theses, Dissertations, and Problem Reports

The increasingly prevalent practice of unconventional technologies has called for the need for the critical analysis of production decline rates to meet economic targets. The high early time production returns and transient flow make matching a production curve to known methods of decline curve analysis problematic.

This research focuses on finding a technique that best fits a known production curve and then applying that technique to another well to check its accuracy. The goal is to find the earliest time of production data necessary to predict an accurate production curve over the lifespan of the well. This is essential to …


Geotechnical Laboratory Testing For 2-D Fem Analysis Of Geomorphic And Planar Sloped Caps And Covers For Sustainable Mine Refuse Deposition, Sun Hee Park Jan 2017

Geotechnical Laboratory Testing For 2-D Fem Analysis Of Geomorphic And Planar Sloped Caps And Covers For Sustainable Mine Refuse Deposition, Sun Hee Park

Graduate Theses, Dissertations, and Problem Reports

This thesis reports the findings of the application of Geomorphic Landform Design principles to the Royal Scot abandoned coarse coal refuse (CCR) pile located in Greenbrier County, West Virginia. The Royal Scot facility has many environmental concerns including severe erosion, acid-mine/rock drainage, and sediment transport. A cap and cover system is proposed to be implemented which incorporates the GLD principles. A two-layer cap and cover system will be used to reclaim the site and return it back to a stable state and reduce the production of acid-mine drainage. The system is composed of a hydraulic barrier composed of compacted CCR, …


Dynamic Model And Estimator Development For A Smart Refractory Brick With Embedded Wireless Sensors For Gasifier Applications, Qiao Huang Jan 2017

Dynamic Model And Estimator Development For A Smart Refractory Brick With Embedded Wireless Sensors For Gasifier Applications, Qiao Huang

Graduate Theses, Dissertations, and Problem Reports

The operating temperature is one of the most important variables for gasifier operation. A higher temperature can shorten the service life of the refractory lining. A lower temperature can reduce the extent of carbon conversion and disrupt the flow of molten slag in a slagging gasifier. Therefore temperature is one of the most important variable in a gasifier. In slagging gasifiers, molten slag can penetrate into the refractory lining leading to refractory spallation, undesired downtime, and costly replacement. Even though the temperature and extent of slag penetration are extremely important for the gasifier operation, they cannot be measured reliably by …


Lateral Torsional Buckling Response In Glass Fiber Reinforced Polymer Composite Beams And Comparison With Ansys Modeling & Design Equations, Santosh Vangala Jan 2015

Lateral Torsional Buckling Response In Glass Fiber Reinforced Polymer Composite Beams And Comparison With Ansys Modeling & Design Equations, Santosh Vangala

Graduate Theses, Dissertations, and Problem Reports

Glass fiber reinforced polymer (GFRP) composites have the potential to replace the existing conventional materials in Civil Engineering like steel and concrete. Such potential can be attributed to the numerous advantages GFRP composites have over conventional materials. Some of the advantages are: high strength-to-weight ratio, corrosion resistance, low life cycle cost and maintenance, nonmagnetic and electronic transparency. As the application of GFRP is on the rise, the need for developing accurate design equations for these materials has been imperative. The GFRP composites are manufactured through pultrusion and although they have numerous advantages they are less stiff than similar profiles made …


Validating The Representativeness Of Test Samples For Performance Prediction Of Face Recognition, Jason Hooks Jan 2015

Validating The Representativeness Of Test Samples For Performance Prediction Of Face Recognition, Jason Hooks

Graduate Theses, Dissertations, and Problem Reports

One of the reasons testing biometric systems is difficult lays in the fact that the test sample available during technology evaluation may not be sufficiently similar to the usage profile that the system will encounter in operations. As the result, performance expectations derived from testing prior to system deployment may not match actual performance after the deployment. A specific instance of this problem occurs when the data from the field in which biometric system will be deployed is sequestered.

In this study, we simulated the stated scenario using two datasets, originally claimed to be similar and adequate for performance prediction; …


Short Wave Infrared Imaging System For Night And Day Long Range Facial Recognition And Surveillance, Robert B. Martin Jan 2015

Short Wave Infrared Imaging System For Night And Day Long Range Facial Recognition And Surveillance, Robert B. Martin

Graduate Theses, Dissertations, and Problem Reports

The capability to detect, observe, and positively identify people at a distance is important to numerous security and defense applications. Traditional solutions for human detection and observation include long-range visible imagers for daytime and thermal infrared imagers for night-time use. Positive identification, through computer face recognition, requires facial imagery that can be repeatably matched to a database of visible spectrum facial mug shots. Nighttime identification at large distances is not possible with visible imagers due to lack of light, or with thermal infrared imagers due to poor correlation with visible facial imagery. An active-SWIR imaging system was developed that is …