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Graduate Theses, Dissertations, and Problem Reports

2018

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Full-Text Articles in Engineering

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 …


Modeling And Evaluation Of A Ridesharing Matching System From Multi-Stakeholders' Perspective, Md Tawhidur Rahman Jan 2018

Modeling And Evaluation Of A Ridesharing Matching System From Multi-Stakeholders' Perspective, Md Tawhidur Rahman

Graduate Theses, Dissertations, and Problem Reports

With increasing travel demand and mobility service quality expectations, demand responsive innovative services continue to emerge. Ridesharing is an established, yet evolving, mobility option that can provide more customized, reliable shared service without any new investment in the transportation infrastructure. To maximize the benefits of ridesharing service, efficient matching and distribution of riders among available drivers can provide a reliable mobility option under most operating conditions. Service efficiency of ridesharing depends on the system performance (e.g., trip travel time, trip delay, trip distance, detour distance, and trip satisfaction) acceptable to diverse mobility stakeholders (e.g., riders, drivers, ridesharing operators, and transportation …


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 …


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 …


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 …


Thermal-Fatigue And Thermo-Mechanical Equivalence For Transverse Cracking Evolution In Laminated Composites, Javier Cabrera Barbero Jan 2018

Thermal-Fatigue And Thermo-Mechanical Equivalence For Transverse Cracking Evolution In Laminated Composites, Javier Cabrera Barbero

Graduate Theses, Dissertations, and Problem Reports

Carbon fiber reinforced plastics (CFRP) are potential materials for many aerospace and aeronautical applications due to their high specif strength/weight and a low coeffcient of thermal expansion (CTE) resulting in a high long-term stability. Among candidate structures, the re-entry reusable launch vehicles (RLV), the fuel oxidant storage and transportation at cryogenic temperature, space satellites, and aircraft structure (frame, wings, etc...) can be highlighted. However, CFRP are prone to internal damage as a result of high residual stresses and thermal fatigue loading. In this study, micro-cracking damage evolution in laminated composites subjected to monotonic cooling and thermal cyclic loads is developed …


Characteristics Of Activated Carbons Produced From Herbaceous Biomass Feedstock, Oluwatosin Jerry Oginni Jan 2018

Characteristics Of Activated Carbons Produced From Herbaceous Biomass Feedstock, Oluwatosin Jerry Oginni

Graduate Theses, Dissertations, and Problem Reports

Energy security and environmental protection are at the forefront of research due to the forecasted depletion of fossil fuel reserves and the growing concern of its adverse environmental impacts. The use of renewable sources for energy applications has centered on the use of biomass feedstocks and this include from herbaceous, woody, agricultural waste, forest residues and municipal wastes. The thermochemical conversion (pyrolysis) of these biomass feedstocks has potential to produce liquid fuel, a solid residue (biochar) and non-condensable gas. The biochar is primarily composed of renewable porous carbon and other inorganic compounds. The biochar is used for soil amendment, adsorption …


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 …


Detection Of Buried Non-Metallic (Plastic And Frp Composite) Pipes Using Gpr And Irt, Jonas Kavi Jan 2018

Detection Of Buried Non-Metallic (Plastic And Frp Composite) Pipes Using Gpr And Irt, Jonas Kavi

Graduate Theses, Dissertations, and Problem Reports

This research investigated alternative strategies for making buried non-metallic pipes (CFRP, GFRP, and PVC) easily locatable using Ground Penetrating Radar (GPR). Pipe diameters up to 12" and buried with up to 4 ft. of soil cover were investigated. The findings of this study will help address the detection problem of non-metallic pipelines and speed the adoption of composite pipes by the petroleum and natural gas industry. The research also investigated the possibility of locating buried pipes transporting hot fluids using Infrared Thermography (IRT).

Results from the study have shown that, using carbon fabric and aluminum tape overlay on non‑metallic pipes …


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 …


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 …


Explanatory And Causality Analysis In Software Engineering, Yasser Ali Alshehri Jan 2018

Explanatory And Causality Analysis In Software Engineering, Yasser Ali Alshehri

Graduate Theses, Dissertations, and Problem Reports

Software fault proneness and software development efforts are two key areas of software engineering. Improving them will significantly reduce the cost and promote good planning and practice in developing and managing software projects. Traditionally, studies of software fault proneness and software development efforts were focused on analysis and prediction, which can help to answer questions like `when’ and `where’. The focus of this dissertation is on explanatory and causality studies that address questions like `why’ and `how’.

First, we applied a case-control study to explain software fault proneness. We found that Bugfixes (Prerelease bugs), Developers, Code Churn, and Age of …


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 …


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 …


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 …


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, …


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 …


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 …


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 …


Applications Of Cellular Components In Engineered Environments, Xiao Hu Jan 2018

Applications Of Cellular Components In Engineered Environments, Xiao Hu

Graduate Theses, Dissertations, and Problem Reports

Manipulation of cellular components in synthetic environment has attracted interest for applications ranging from sensors to nanelectronics and from catalysis to biomedical devices. In such applications, biological-based processes such as specific recognition and self-assembly direct the formation of hierarchical structures, all at minimum energetic costs, with high efficiency and reliability.

Among such cellular machines, microtubules and kinesins have attracted special interest. Inside the cells, microtubules are giving structural integrity while serving as regular and uniform tracks for transport of vesicles or organelles. Kinesin uses a microtubule track in vivo to progress to specific locations with processive and coordinated steps, all …


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 …


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, …


Hydrogeology And Water Management In The Arkwright Underground Coal Mine, Pittsburgh Seam, Northern West Virginia, Bryant D. Mountjoy Jan 2018

Hydrogeology And Water Management In The Arkwright Underground Coal Mine, Pittsburgh Seam, Northern West Virginia, Bryant D. Mountjoy

Graduate Theses, Dissertations, and Problem Reports

Arkwright #1 is a closed underground mine in the Pittsburgh coal seam near Morgantown, West Virginia USA. Arkwright shares perimeter boundaries/barriers with three other closed Pittsburgh seam mines (Osage #3, Jordan #93, Federal #1) and is partially overlain by flooded Sewickley seam mines, 25 m above it. This mine is significant primarily because it manages and treats water diverted from nearly 20 other closed mines over a 600 square kilometer area. This study examines water levels, pump records, and mine maps to describe the hydrogeology of Arkwright Mine. After closure in 1995, Arkwright and the adjacent northern Osage mines began …


Study Of Biomimetic Micro And Macro Structures For Drag Reduction, Justin S. Schrout Jan 2018

Study Of Biomimetic Micro And Macro Structures For Drag Reduction, Justin S. Schrout

Graduate Theses, Dissertations, and Problem Reports

The ever increasing demand for global travel coupled with increasing costs of fuels have prompted many researchers to study new methods to save fuel to make travel more efficient. One of the proverbial low-hanging fruits for fuel efficiency is aerodynamic drag reduction. Simple changes in the shape or placement of structures on the surface of different types of vehicles have been shown to increase fuel efficiency by reducing drag (e.g., add-on lower and aft wake fairings on tractor trailers which have seen a tremendous rise in popularity on US highways in recent years). Areas of interest in drag reduction have …


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 …


Blockchain For Trustful Collaborations Between Immigrants, Citizens And Governments, Chun-Wei Chiang Jan 2018

Blockchain For Trustful Collaborations Between Immigrants, Citizens And Governments, Chun-Wei Chiang

Graduate Theses, Dissertations, and Problem Reports

mmigrants usually are pro-social towards their hometowns and try to improve them. However, the lack of trust in their government can drive immigrants to work individually. As a result, their pro-social activities are usually limited in impact and scope. Although blockchain technology have the potential to solve the trust issue, people are not familiar with the technology and they have no idea why it is trustworthy. Previous research showed that the adopting user interface properly can increase people's trust in technology. This paper studies the interface factors that ease collaborations between immigrants and their home governments. We specifically focus on …


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 …


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 …


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 …


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 …