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Masters Theses

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Full-Text Articles in Engineering

Low Noise Nmos Imager Fabrication With A Study On The Effect Of Photodiode Shape On Dark Current, Steven Taylor Apr 2014

Low Noise Nmos Imager Fabrication With A Study On The Effect Of Photodiode Shape On Dark Current, Steven Taylor

Masters Theses

The purpose of this project was to fabricate a low noise N-type Metal-Oxide- Semiconductor (NMOS) imager in the Grand Valley State University (GVSU) Cleanroom with a focus on reducing pixel dark current. Previous research suggests Photodiode (PD) shape affects dark current and charge transfer characteristics of the pixel. Five PD shapes were designed to determine an optimized pixel shape with respect to dark performance. PN junction PDs with the Three Transistor (3T) pixel architecture were found to be the most suitable for imager fabrication in the GVSU cleanroom. The integrated circuit layout of several 8x8 pixel arrays was designed to …


An Analysis Of Burn Cut Pull Optimization Through Varying Relief Hole Depths, Michael Robert Allen Jan 2014

An Analysis Of Burn Cut Pull Optimization Through Varying Relief Hole Depths, Michael Robert Allen

Masters Theses

"In underground blasting, the pull of the initial cut is the limiting factor for the success of the rest of the round. By improving the pull of the first cut, a critical step is made towards improving the entire round. This project attempted to optimize a burn cut's effective pull by varying the depths of the relief holes in the burn, and then analyzing the results. In testing, relief holes were drilled to depths both shorter and longer than that of the cut's charged holes. The overall objective was to consistently achieve greater pull than in a standard burn, using …


Analysis And Modeling Of Resilience For Networked Systems, Kamlesh Ashok Joshi Jan 2014

Analysis And Modeling Of Resilience For Networked Systems, Kamlesh Ashok Joshi

Masters Theses

"A cyber physical system (CPS) has two main subsystems; a physical infrastructure that is responsible for managing and implementing physical tasks, e.g., generation and distribution of a physical commodity, and a cyber infrastructure that is used to support and enhance these physical operations through computing, communication, and control. Imperfect cyber control can lower the efficacy and even reliability of existing physical infrastructures. As such, justifiable reliance on CPSs requires rigorous investigation of the effect of incorporating cyber infrastructure on functional and non-functional aspects of system performance. One non-functional metric of note is resilience, defined as the ability of a system …


Fair And Optimal Resource Allocation In Wireless Sensor Networks, Vinodhini Ravikumar Jan 2014

Fair And Optimal Resource Allocation In Wireless Sensor Networks, Vinodhini Ravikumar

Masters Theses

"There is a large amount of research in wireless networks focuses on optimization of either network routing and power control alone. In contrast, this work aims at jointly optimizing the transmission power and routing path selection in order to optimize allocation of resources in interference constrained wireless environment. Moreover, we consider a multipath routing where multiple alternative paths are employed to transmit data between the end nodes. One of modern communication techniques that it applies to a network coding, though not explicitly implemented in this work. The proposed approach is first analyzed theoretically using Lagrangian optimization for a three-node scenario. …


Shear Behavior Of High Strength Self-Consolidating Concrete In Nu Bridge Girders, Alexander Michael Griffin Jan 2014

Shear Behavior Of High Strength Self-Consolidating Concrete In Nu Bridge Girders, Alexander Michael Griffin

Masters Theses

"As the nation's infrastructure continues to age, advanced concrete technologies have been developed to both reduce a structure's costs and increase its life expectancy. Since the early 1990's, self-consolidating concrete (SCC) has been one of these technologies. Many, however, have been reluctant to implement SCC in highway girders due to the mixture constituents. One of these concerns is the reduced content and size of the coarse aggregate. These differences in the concrete potentially hinder SCC's mechanical properties and shear resistance. Additionally, for high strength concretes (HSC) with weaker aggregates, shear cracks tend to propagate through the coarse aggregate, reducing the …


Performance Comparison Of Transverse And Longitudinal Fractured Horizontal Wells Over Varied Reservoir Permeability, Fen Yang Jan 2014

Performance Comparison Of Transverse And Longitudinal Fractured Horizontal Wells Over Varied Reservoir Permeability, Fen Yang

Masters Theses

"Since the first application in the mid-1980's, multiple fractured horizontal wells have proven to be an effective means of extracting hydrocarbons. These wells require careful consideration of wellbore orientation relative to the horizontal principle stress. Wellbore orientation can lead to transverse fractures which are perpendicular to the wellbore, or longitudinal fractures parallel the wellbore. Questions arise regarding whether one fracture orientation is consistently preferred over the other, or if certain conditions affect the choice.

Historical work has examined the impact of horizontal wellbore azimuth in the Barnett and Marcellus Shale where public data was reviewed and statistical well analysis was …


Islanding Technique In Power Systems To Avoid Cascading Failure, Saurabh Sahasrabuddhe Jan 2014

Islanding Technique In Power Systems To Avoid Cascading Failure, Saurabh Sahasrabuddhe

Masters Theses

"In order to increase the reliability of the power system and to make use of trapped generation potential from renewable sources due to lack of transmission availability, the interconnection of modern day power systems is increasing day by day. Lack of timely response to the ramping load and high degree of interconnection can lead to cascading failures. Upon inception, these can spread through the system within seconds and may result in a total system blackout.

Natural calamities and erroneous operations of components are often the causes of system disturbances. The type and the location of these disturbances determine it's impact …


The Effect Of Using Different Rock Failure Criteria In Wellbore Stability Analysis, Reza Rahimi Jan 2014

The Effect Of Using Different Rock Failure Criteria In Wellbore Stability Analysis, Reza Rahimi

Masters Theses

"Determination of the appropriate drilling fluid density by rock failure analysis is an essential step to control wellbore instability. To determine wellbore failure stresses, the rock strength has to be known, an appropriate constitutive model has to be selected, and finally an accurate rock failure criterion must be chosen. Linear-poro elastic modeling of the mechanical wellbore failure is the most common approach to investigate wellbore instability. Numerous failure criteria have been used for the rock failure analysis but there is not any commonly accepted agreement of which failure criteria to use. Rock failure criteria differ in two main characteristics. First, …


Inorganic Biodegradable Devices For Temporary Implants, Kassan Unda Jan 2014

Inorganic Biodegradable Devices For Temporary Implants, Kassan Unda

Masters Theses

"Implantable electronic devices have great potential to benefit many health care technologies. They comprise of two different categories. The first is permanent prosthetic devices like cardiac pacemakers or nerve stimulants. The other category includes temporary devices for interventional medical monitoring and control scenarios, which lose functionality and become unnecessary after their intended operational lifetime. This can cause serious electromagnetic and biomechanical safety concerns if not removed from the body by an additional surgical operation.

This thesis focuses on exploring the feasibility of implantable inorganic bioresorbable thin film resistive devices utilizing bioactive glass as the core structural material. This device will …


Mechanistic Identification Of Specific Force Coefficients In Endmilling Inconel 718 Under Four Cooling Strategies, Mahmood Shaman Ameen Jan 2014

Mechanistic Identification Of Specific Force Coefficients In Endmilling Inconel 718 Under Four Cooling Strategies, Mahmood Shaman Ameen

Masters Theses

“This thesis presents the results of experimental investigations of the mechanistic identification of specific force coefficients for uncoated bull-nose and uncoated wavy-edge/bull-nose helical endmilling of Inconel 718 under emulsion, minimum quantity lubrication (MQL), cryogenic (LN2), and combined (MQL + LN2) cooling. Several slot milling tests were conducted on Inconel 718 workpiece block with depth of cut 1.25 mm. The cutting parameters were varied as: spindle speed, n = 250 and 750 rev/min, feedrate, f = 25–75 mm/min by using uncoated carbide bull-nose helical endmill. Also 24 peripheral milling tests were conducted on Inconel 718 workpiece block …


Machinability Improvement During High-Speed End-Milling Of Inconel 718 Alloy, Chukwujekwu Nnadi Jan 2014

Machinability Improvement During High-Speed End-Milling Of Inconel 718 Alloy, Chukwujekwu Nnadi

Masters Theses

“This thesis presents the results of the experimental investigation of the effects of machining parameters (spindle speed and feedrate) and cooling strategies [Minimum Quantity Lubrication (MQL), Cryogenic Liquid Nitrogen (LN2), and combined (MQL+LN2)] on cutting force components, cutting temperature, tool wear and surface roughness during high-speed slot end-milling of Inconel 718 alloy. In addition, a comparative evaluation of the three cooling strategies was conducted for cutting force components, surface roughness and residual stresses. All end-milling experiments were conducted on a Cincinnati Milacron Vertical Machining center (VMC), using a 0.5 inch (12.7 mm) diameter, 0.03 inch (0.762 …


Software-Based Instrumentation For Analysis Of Electrostatic Discharge Effects, Antonio James Sabatini Jan 2014

Software-Based Instrumentation For Analysis Of Electrostatic Discharge Effects, Antonio James Sabatini

Masters Theses

”Failures caused by electrostatic discharge (ESD) compromise the reliability of embedded systems. Peripherals such as the universal serial bus (USB) are particularly vulnerable, as isolating them to avoid electromagnetic interference would defy their purpose - facilitating communication with and/or by the embedded system. Better understanding the propagation of failures that result from ESD can facilitate defensive development of hardware and software for embedded systems, but is hampered by the lack of non-invasive and lightweight instrumentation techniques.

The original contribution of this thesis is the design and development of software-based instrumentation for monitoring the reaction of the USB peripheral of an …


Workplace Sleepiness: Causes, Consequences And Countermeasures, Neda Khalafi Jan 2014

Workplace Sleepiness: Causes, Consequences And Countermeasures, Neda Khalafi

Masters Theses

"Sleep deprivation is an epidemic problem in our society that adversely affects the quality and safety of our daily lives. At home and on the job, inadequate sleep is associated with considerable social, financial, and health-related costs, due to instability of waking functions. Research has shown that, sleep deprivation among workers, whether from sleep disorders, lifestyle or shift work, can hinder the proper performance, and in extreme cases may pose hazard to the workers themselves and their environment. Deficits in daytime performance can have profound effects in the processing industry where workers are often required to perform monotonous tasks that …


Data Classification And Forecasting Using The Mahalanobis-Taguchi Method, Adebolaji A. Jobi-Taiwo Jan 2014

Data Classification And Forecasting Using The Mahalanobis-Taguchi Method, Adebolaji A. Jobi-Taiwo

Masters Theses

"Classification and forecasting are useful concepts in the field of condition monitoring. Condition monitoring refers to the analysis and monitoring of system characteristics to understand and identify deviations from normal operating conditions. This can be performed for prediction, diagnosis, or prognosis or a combination of any these purposes. Fault identification and diagnosis are usually achieved through data classification, while forecasting methods are usually used to accomplish the prediction objective. Data gathered from monitoring systems often consists of multiple multivariate time series and is fed into a model for data analysis using various techniques. One of the data analysis techniques used …


An Interactive Product Development Model In Remanufacturing Environment: A Chaos-Based Artificial Bee Colony Approach, Vishwa V. Kumar Jan 2014

An Interactive Product Development Model In Remanufacturing Environment: A Chaos-Based Artificial Bee Colony Approach, Vishwa V. Kumar

Masters Theses

"This research presents an interactive product development model in re-manufacturing environment. The product development model defined a quantitative value model considering product design and development tasks and their value attributes responsible to describe functions of the product. At the last stage of the product development process, re-manufacturing feasibility of used components is incorporated. The consummate feature of this consideration lies in considering variability in cost, weight, and size of the constituted components depending on its types and physical states.

Further, this research focuses on reverse logistics paradigm to drive environmental management and economic concerns of the manufacturing industry after the …


Potential Acid Mine Drainage Treatment Utilizing Acidophilic Sulfate Reducing Bacteria In An Upflow Bioreactor, Elise Fay Kittrell Jan 2014

Potential Acid Mine Drainage Treatment Utilizing Acidophilic Sulfate Reducing Bacteria In An Upflow Bioreactor, Elise Fay Kittrell

Masters Theses

"During coal and iron mining, pyrite is often exposed to oxygen, causing acid mine drainage (AMD). Acid mine drainage has characteristic traits of: a rust color, low pH levels (around 3 or 4) and high concentrations of sulfate, metal sulfates and heavy metals.

Sulfate reducing bacteria (SRB) are often utilized in acid mine drainage treatment by implementing them into biochemical reactors (BCR). As SRB break down various carbon sources, bicarbonate is produced, raising the pH and generating hydrogen sulfide which reacts with numerous metals. This approach can be troublesome, as SRBs do not thrive at low pH levels often associated …


Numerical Simulations For Wellbore Stability And Integrity For Drilling And Completions, Nevan Christopher Himmelberg Jan 2014

Numerical Simulations For Wellbore Stability And Integrity For Drilling And Completions, Nevan Christopher Himmelberg

Masters Theses

"Conventional wellbore trajectory planning is commonly based on an Andersonian state of stress [SoS] and the optimum well azimuth and inclination for a specific depth can be determined using stereographic projections of the safe mud weight window. In this thesis a new methodology using the complete stress tensor is developed to determine optimal well trajectories for complex in-situ stress scenarios. This study uses a 3D finite element analysis to simulate the SoS based on an integrated 3D MEM. The model yields the complete stress tensor at every location for a planned future well path. Using standard equations to determine the …


Updated Screening Criteria For Steam Flooding Based On Oil Field Projects Data, Mariwan Qadir Hama Jan 2014

Updated Screening Criteria For Steam Flooding Based On Oil Field Projects Data, Mariwan Qadir Hama

Masters Theses

"Enhanced oil recovery (EOR) screening is considered the first step in evaluating potential EOR techniques for candidate reservoirs. Therefore, as new technologies are developed, it is important to update the screening criteria. Many of the screening criteria for steam flooding that have been described in the literature were based on data collected from EOR surveys biennially published in the Oil & Gas Journal. However, these datasets contain some problems, including outliers, missing data, inconsistent data and duplicate data, that could affect the accuracy of the results. Despite the importance of ensuring the quality of a dataset before running analyses, data …


Bridge Deck Condition Assessment Using Destructive And Nondestructive Methods, Brandon Tyler Goodwin Jan 2014

Bridge Deck Condition Assessment Using Destructive And Nondestructive Methods, Brandon Tyler Goodwin

Masters Theses

"This study investigates two bridge decks in the state of Missouri using both nondestructive and destructive testing methods. The Missouri Department of Transportation (MoDOT) is responsible for the monitoring and maintenance of over 10,000 bridges. Currently monitoring of these bridges includes a comprehensive visual inspection. In this study, ground-coupled ground penetrating radar (GPR) is used to estimate deterioration, along with other traditional methods, including visual inspection, and core evaluation. Extracted core samples were carefully examined, and the volume of permeable pore space was determined for each core. After the initial investigation, the two bridges underwent rehabilitation using hydrodemolition as a …


Improving Plasma Actuator Performance At Low Pressure, And An Analysis Of The Pointing Capabilities Of Cubesats Using Plasmonic Force Propulsion (Pfp) Thrusters, Paul Daniel Friz Jan 2014

Improving Plasma Actuator Performance At Low Pressure, And An Analysis Of The Pointing Capabilities Of Cubesats Using Plasmonic Force Propulsion (Pfp) Thrusters, Paul Daniel Friz

Masters Theses

"This thesis details the work done on two unrelated projects, plasma actuators, an aerodynamic flow control device, and Plasmonic Force Propulsion (PFP) thrusters, a space propulsion system for small satellites.

The first half of the thesis is a paper published in the International Journal of Flow Control on plasma actuators. In this paper the thrust and power consumption of plasma actuators with varying geometries was studied at varying pressure. It was found that actuators with longer buried electrodes produce the most thrust over all and that they substantially improved thrust at low pressure. In particular actuators with 75 mm buried …


Effect Of Stress Concentrations On Fatigue Of Composite And Metallic Structures, Ross Henry Falen Jan 2014

Effect Of Stress Concentrations On Fatigue Of Composite And Metallic Structures, Ross Henry Falen

Masters Theses

"The complex shapes of hydrokinetic turbine blades can include part features such as a fillet, step, or hole. Situations can arise where two part features, such as a hole and a fillet, may be in close proximity which can introduce stress concentrations within the blade structure, adversely affecting the structure's life. Because the interaction between the part features isn't well known, fatigue data is needed to determine the proper analysis.

In this thesis, two separate topics are discussed and investigated. The first topic deals with stress concentrations in hydrokinetic turbine blades. Several blade designs were tested and improved upon to …


Analysis Of Factors Responsible For Life Degradation Of Led Traffic Indicators In The State Of Missouri, Snehal Satish Digraskar Jan 2014

Analysis Of Factors Responsible For Life Degradation Of Led Traffic Indicators In The State Of Missouri, Snehal Satish Digraskar

Masters Theses

"Traffic lights using state-of-the-art LED illumination use 90 percent less electricity and offer a much longer service life and durability than their incandescent counterparts. Taking advantage of the countless benefits, cities around the country have been replacing traditional filament-based traffic signal bulbs with LEDs for years. However, the degradation of LEDs and hence the replacement strategy, are a concern which is faced by most of the Departments of Transportation. The thesis work sponsored by MoDOT, presents the replacement strategy developed based on the field study of LED indicators in Missouri. Three types of analysis are performed with multiple data point …


Application Of Electrically Invisible Antennas To The Modulated Scatterer Technique, Dylan Andrew Crocker Jan 2014

Application Of Electrically Invisible Antennas To The Modulated Scatterer Technique, Dylan Andrew Crocker

Masters Theses

"The Modulated Scatterer Technique (MST) has shown promise for applications in microwave imaging, electric field mapping, and materials characterization. Traditionally, MST scatterers consist of dipole antennas centrally loaded with a lumped element capable of modulation (commonly a PIN diode). By modulating the load element, the signal scattered from the MST scatterer is also modulated. However, due to the small size of such scatterers, it can be difficult to reliably detect the modulated signal. Increasing the modulation depth (a parameter related to how well the scatterer modulates the scattered signal) may improve the detectability of the scattered signal. In an effort …


Modelling Of Directed Energy Deposition Processes, Xueyang Chen Jan 2014

Modelling Of Directed Energy Deposition Processes, Xueyang Chen

Masters Theses

"The laser additive manufacturing technique of laser deposition allows quick fabrication of fully-dense metallic components directly from Computer Aided Design (CAD) solid models. The applications of laser deposition include rapid prototyping, rapid tooling and part refurbishment. The development of an accurate predictive model for laser deposition is extremely complicated due to the multitude of process parameters and materials properties involved. In this work, a heat transfer and fluid flow model is developed.

In the heat transfer and fluid flow model, the governing equations for solid, liquid and gas phases in the calculation domain have been formulated using the continuum model. …


Comparison Of Core Control And Geophysical Investigations, Silica Sand Deposits, Dawmat Al Jandal, Al Jawf At Saudi Arabia, Ghassan Salem Alsulaimani Jan 2014

Comparison Of Core Control And Geophysical Investigations, Silica Sand Deposits, Dawmat Al Jandal, Al Jawf At Saudi Arabia, Ghassan Salem Alsulaimani

Masters Theses

"This thesis is a summary of a comprehensive geophysical investigation in southern Dawmat Al Jandal, Al Jawf in Saudi Arabia. This research demonstrates that the acquisition of both core control and geophysical data is superior to the acquisition of core control alone. Coring is expensive and is limited in subsurface coverage. Geophysical surveying, however, is a relatively rapid and cost-effective means of deriving information about the subsurface between core holes. Ground penetrating radar (GPR), Multichannel Analysis of Surface Waves (MASW), and Seismic Refraction methods were used as exploration techniques to locate surficial mineral deposits within the study area.

During the …


Comparison Of Costs Of Personal Protective Equipment For All Workers To Avoid Costs Of Fall Accidents, Sultan Noori Al-Karawi Jan 2014

Comparison Of Costs Of Personal Protective Equipment For All Workers To Avoid Costs Of Fall Accidents, Sultan Noori Al-Karawi

Masters Theses

"The construction industry is one of the most important industries in the United States. It is the biggest contributor in the growth of the U.S. economy. Despite the great achievements and prominent role for this sector in the U.S. economy, the construction industry is suffering from neglect and dereliction by related government institutions and private companies. This neglect led to formation of a negative image about the construction industry that has caused a deep impact in productivity and economic growth. One of the reasons is a high percentage of accidents that occur within the construction industry which leads to injuries …


Theoretical Analysis Of Shape Separation Of Particles Using Flow Field-Flow Fractionation, Mehrdad Alfi Jan 2014

Theoretical Analysis Of Shape Separation Of Particles Using Flow Field-Flow Fractionation, Mehrdad Alfi

Masters Theses

"Size separation of spherical and rod-like particles in Flow Field-flow Fractionation was investigated theoretically. The effect of cross flow migration and rod orientation was also investigated as a new mode of study. It has been shown that the rod local orientation makes different diffusivity values in comparison with spherical particles and helps particle separation. Additionally, a new mechanism of lift-hypelayer mode was used for rod-like particles which can be compared with steric mode of spherical particles. This mechanism is said to be due to hydrodynamic interaction of rod-like particle with wall and with other rods.

As a measure of axial …


Impact Of Fracture Spacing And Mechanical Parameter Anisotropy On Fracture Width In Horizontal Wells In Shales, Deepak Gokaraju Jan 2014

Impact Of Fracture Spacing And Mechanical Parameter Anisotropy On Fracture Width In Horizontal Wells In Shales, Deepak Gokaraju

Masters Theses

"The success of economically viable production of oil and gas from ultra-low permeability shale reservoirs depends on the creation of an extensive fracture network through hydraulic fracture stimulation. Multiple hydraulic fractures are created simultaneously in each stage to increase the surface area of contact between the wellbore and reservoir. The spacing between fractures is an important component to consider when developing an optimum stimulation design. An important aspect of shale rock properties is that shales are inherently anisotropic with a horizontal plane of isotropy (transversely isotropic) due to their finely layered structure. This study aims to provide an insight into …


An Analytical Pressure Model To Guide Downhole Sensor Placement For Carbon Dioxide Sequestration Monitoring, Yilin Mao Jan 2014

An Analytical Pressure Model To Guide Downhole Sensor Placement For Carbon Dioxide Sequestration Monitoring, Yilin Mao

Masters Theses

"Injecting CO₂ into saline aquifers is currently the most viable approach to mitigate global greenhouse gas effect. Various monitoring techniques are required to achieve 99% accuracy in determining the location of the injected CO₂ plume. Sensor locations are critical to the monitoring quality necessary to meet this requirement but have scarcely been discussed. The pressure profile needs to be modeled accurately at the initial stage of CO₂ injection to guide sensor locations. The objective of this thesis was to develop an analytical solution for CO₂ sequestration based on time and distance. This will guide the locations of downhole pressure sensors …


Thermal Properties Of Zirconium Diboride - Transition Metal Boride Solid Solutions, Devon Lee Mcclane Jan 2014

Thermal Properties Of Zirconium Diboride - Transition Metal Boride Solid Solutions, Devon Lee Mcclane

Masters Theses

"This research focuses on the thermal properties of zirconium diboride (ZrB₂) based ceramics. The overall goal was to improve the understanding of how different transition metal (TM) additives influence thermal transport in ZrB₂. To achieve this, ZrB₂ with 0.5 wt% carbon, and 3 mol% of individual transition metal borides, was densified by hot-press sintering. The transition metals that were investigated were: Y, Ti, Hf, V, Nb, Ta, Cr, Mo, W, and Re. The room temperature thermal diffusivities of the compositions ranged from 0.331 cm²/s for nominally pure ZrB₂ to 0.105 cm²/s for (Zr,Cr)B₂ and converged around 0.155cm²/s at higher temperatures …