Digital Commons Network^™

A Cost-Benefit Analysis Of Community Health Workers‘ Impact Upon The Birth Outcomes Of At-Risk Pregnant Women In Muskegon County, Edward Michael Jados

Masters Theses

The purpose of this case study was to investigate the effects of community health workers (CHWs) on at-risk pregnant women in Muskegon County through a cost-benefit analysis. CHWs are selected, trained and working in the communities from which they live. The role of the community health worker is extremely diverse, usually due to the communities and programs that they serve. Their purpose is to improve health outcomes in the communities they serve by increasing access to and coverage to basic health services and needs, notably for underserved and medically needy populations. Previous studies have showed that CHWs have a positive …

Wind Energy Assessment Using A Wind Turbine With Dynamic Yaw Control, Md Nahid Pervez

Masters Theses

The goal of this project was to analyze the wind energy potential over Lake Michigan. For this purpose, a dynamic model of a utility-scale wind turbine was developed to estimate the potential electrical energy that could be generated. The dynamic model was supported by wind data collected by an unmanned buoy based Laser Wind Sensor data acquisition system that has been deployed in Lake Michigan since October, 2011. Data summarization tools were also developed to help profile the wind resource based on the collected data.

Paste Development And Co-Sintering Test Of Zirconium Carbide And Tungsten In Freeze-Form Extrusion Fabrication, Ang Li

Masters Theses

"Ultra-high temperature ceramics are being investigated for future use in aerospace applications due to their superior thermo-mechanical properties, as well as oxidation resistance, at temperatures above 2000°C. However, their brittle properties make them susceptible to thermal shock failure. Components fabricated as functionally graded materials (FGMs) can combine the superior properties of ceramics with the toughness of an underlying refractory metal by fabricating graded composites. This paper discusses the grading of two materials through the use of a Freeze-form Extrusion Fabrication (FEF) system to build FGMs parts consisting of zirconium carbide (ZrC) and tungsten (W). Aqueous-based colloidal suspensions of ZrC and …

Security Analysis Of A Cyber Physical System : A Car Example, Jason Madden

Masters Theses

"Deeply embedded Cyber Physical Systems (CPS) are infrastructures that have significant cyber and physical components that interact with each other in complex ways. These interactions can violate a system's security policy, leading to the leakage of rights and unintended information flow. This thesis will explore information flow as it uses a public channel. In order to exemplify the use of the public channel, a vehicle being composed of the computer system and its operators will show how information is disclosed to an observer. The example is made up of a vehicle traveling across some terrain with an observer watching the …

Quantization Noise Analysis Of A Closed-Loop Pwm Controller That Includes Σ-Δ Modulation, Anupama Balakrishnan

Masters Theses

"Σ-Δ modulation is a popular noise shaping technique which is used to move the quantization noise out of the frequency band of interest. Recently, a number of authors have applied this technique to a pulse width modulation (PWM) controller for switching power converters. However, previous analysis has not incorporated the effects of analog-to-digital converter (ADC) resolution or feedback control on the Σ-Δ modulator. In this work, quantization due to ADC resolution and PWM resolution are analyzed, considering the effects of noise-shaping and feedback. A number of simulations have been performed to explore the impact of various design choices on output …

Robust Methods For Construction Of Global Potential Energy Surfaces, Phalgun Lolur

Masters Theses

"This thesis is about the development of robust methods for construction of global potential energy surfaces to study the spectroscopy and dynamics of molecular systems. A potential energy surface represents the electronic energy of a molecule as a function of its geometry. This is central to how chemists view molecular systems in terms of motion across a rich energy landscape where barriers separate wells corresponding to different stable structures. The range of molecular distortions defines the potential energy surface. Computing the potential energy surface of a molecule has become a fundamental operation in modern theoretical chemistry studies. The Born-Oppenheimer approximation …

Immersed Finite Element Method For Interface Problems With Algebraic Multigrid Solver, Wenqiang Feng

Masters Theses

"This thesis is to discuss the bilinear and 2D linear immersed finite element (IFE) solutions generated from the algebraic multigrid solver for both stationary and moving interface problems. In contrast to the body-fitting mesh restriction of the traditional finite element methods or finite difference methods for interface problems, a number of numerical methods based on structured meshes independent of the interface have been developed. When these methods are applied to the real world applications, we often need to solve the corresponding large scale linear systems many times, which demands efficient solvers. The algebraic multigrid (AMG) method is a natural choice …

Transmission Shaft Design For Hydrokinetic Turbine With Reliability Consideration, Goutham Pusapati

Masters Theses

"Hydrokinetic energy, a relatively new kind of renewable energy, can be generated from flowing water in rivers or oceans. Hydrokinetic turbines (HKTs) are a major system for hydrokinetic energy, and the reliability of the HKTs is critical for both their lifecycle cost and safety. The objective of this work is to apply advanced methodologies of reliability analysis and reliability-based design to the transmission shaft design for a horizontal-axis, non-submerged HKT. The deterministic shaft design is performed first by considering failure modes of strength and deflection using distortion energy, maximum shear and deflection theories. Then the reliability analysis of the shaft …

Wolf Creek Dam: A Case Study Of Foundation Remediation For Dams Built On Karst Foundations, Kyla Justene Erich

Masters Theses

"Wolf Creek Dam was completed in 1952 as a 5,736-foot long and 258-foot high combination embankment-concrete gravity dam. Its storage capacity of 6 million acre feet makes it the ninth largest reservoir in the nation. The dam was built on a heavily karstified limestone foundation and began exhibiting signs of excess foundation seepage in late 1967. This led to extensive corrective work in the 1970s beneath the earthen core of the embankment to reduce underseepage. In 2006 an independent assessment by the Dam Safety Action Classification (DSAC) Peer Review Panel recommended that Wolf Creek Dam exhibited "Urgent and Compelling" foundation …

Search-Based Model Summarization, Lokesh Krishna Ravichandran

Masters Theses

"Large systems are complex and consist of numerous components and interactions between the components. Hence managing such large systems is a cumbersome and time consuming task. Large systems are usually described at the model level. But the large number of components in such models makes it difficult to modify. As a consequence, developers need a solution to rapidly detect which model components to revise. Effective solution is to generate a model summary. Although existing techniques are powerful enough to provide good summaries based on lexical information (relevant terms), they do not make use of structural information (component structure) well. In …

Effect Of Mix Parameters On Longevity Of Bituminous Mixtures, Clayton Reichle

Masters Theses

"This study was performed to evaluate the effects of varying aggregate sources, aggregate gradations on the stripping and rutting potential of bituminous based plant mixes specified by the Missouri Department of Transportation. The different aggregate combinations included two different aggregate sources (Potosi Dolomite and Jefferson City Dolomite) including two variations for the Jefferson City Dolomite mix to simulate a marginally in-specification mix and an out-of-specification but in-field tolerance mix. The "field" mix simulated the marginal mix where field tolerance of high dust and low binder content were maximized. All three mixes were evaluated for stripping susceptibility using the Tensile Strength …

Secure Design Defects Detection And Correction, Wenquan Wang

Masters Theses

"Bad design and software defects often make source codes hard to understand and lead to maintenance difficulties. In order to detect and fix such defects, researchers have systematically investigated these issues and designed different effective algorithms to tackle the problems. However, most of these methods need source codes/models for defect detection and correction. Commercial companies, like banks, may not be willing to provide their source models due to data security. Therefore, it is a huge challenge to detect software detects by a consulting company as well as to keep source models confidential. This thesis analyze security issues in existing approaches …

Lexis In Chemical Engineering Discourse: Analyzing Style In Chemical Engineering Research Articles Through A Rhetorical Lens, David Lamar Young

Masters Theses

"This study examines the style of chemical engineering research articles to discover stylistic trends that may be applicable to authors looking to publish their own research. Rhetorical stylistic analysis was used as a research method to allow for thorough analysis of all articles in the sample. Ten research articles from the two prominent chemical engineering journals were chosen using specific criteria to constitute a sample of articles that could most accurately represent the population of chemical engineering research articles. Each article was then analyzed line by line to identify markers of chemical engineering research article style, including the following: ▬Use …

New Sensorless, Efficient Optimized And Stabilized V/F Control For Pmsm Machines, Seyed Hesam Jafari

Masters Theses

"With the rapid advances in power electronics and motor drive technologies in recent decades, permanent magnet synchronous machines (PMSM) have found extensive applications in a variety of industrial systems due to its many desirable features such as high power density, high efficiency, and high torque to current ratio, low noise, and robustness. In low dynamic applications like pumps, fans and compressors where the motor speed is nearly constant, usage of a simple control algorithm that can be implemented with least number of the costly external hardware can be highly desirable for industry. In recent published works, for low power PMSMs, …

Communication Protocols For Integrated Fiber Optic Sensor Interrogator, Tameem Ahmed Khan

Masters Theses

"Fiber optic sensors have gained rapid recognition in sensing environmental factors such as strain, stress, acoustics, pressure, temperature among emerging other sensing applications. Major advantages of fiber based systems are small size, light weight, multiplex-ability of sensors on a single fiber, and immunity to Radio Frequency (RF) interference. However, single most major disadvantage of such technology is that traditionally the interrogation systems are typically bulky and heavy lab only equipment. Embed-ability of sensors into different structures and environments requires that the whole systems (sensors + interrogator) be small, modular and portable. This thesis presents such a custom Fiber optic Sensor …

Constructing Conducted Emission Models For Integrated Circuits, Shuai Jin

Masters Theses

"Conducted emissions, noise conducted out of integrated circuit pins, play an important role in determining the system level EMC performance. Characterizing conducted emissions from ICs is investigated and the corresponding noise models are developed in this thesis. Both simulation IBIS and measurement based methods for noise-model construction are studied. The constructed noise source model for a test IC is applied in system-level simulations and the calculated far field radiation is validated with measurements. The agreement in the simulated and measured results demonstrates the effectiveness of the constructed model for characterizing the conducted emissions from an IC I/O pin"--Abstract, page iii.

Tensile Failure During Structural Development Of Single-Layer Buckle Folds, Xiaolong Liu

Masters Theses

"Folds and fold trains of sedimentary strata are among the most common structural traps systems for hydrocarbon reservoirs. The existence of tensile fractures associated to buckle folding is associated to the distribution of extensional strain in the outer arc of the fold hinges. This study investigates the conditions under which tensile stresses develop due to buckling in a realistic in situ stress scenario. By applying a 2D finite element modeling approach, the influence of realistic mechanical stratigraphy (including strain rate, overburden depth, competence contrasts, viscosity, and permeability) on the development of single-layer buckle folds with Newtonian viscous rheology is studied. …

Gas And Water Flow Through Nanoscale Porous Media, Songyuan Liu

Masters Theses

"This work provides a lab experiment to describe the fluid diffusion in nanoscale porous media. By using ideal ceramic membranes which have uniform pore size in nanoscale and homogeneous pore distribution instead of shale or tight sandstone which have various pore sizes and complicated pore distribution and structure, a better understanding of fluid flow through nanoscale porous media could be gained.

Core flooding test were conducted by injecting nitrogen and water separately to describe gas and liquid flow in nanoscale porous media. With all the other factors known or controlled, pressure and flow rate were measured to calculate permeability. By …

Predicting Solar Radiation Based On Available Weather Indicators, Frank Joseph Sauer

Masters Theses

"Solar radiation prediction models are complex and require software that is not available for the household investor. The processing power within a normal desktop or laptop computer is sufficient to calculate similar models. This barrier to entry for the average consumer can be fixed by a model simple enough to be calculated by hand if necessary.

Solar radiation modeling has been historically difficult to predict and accurate models have significant assumptions and restrictions on their use. Previous methods have been limited to linear relationships, location restrictions, or input data limits to one atmospheric condition. This research takes a novel approach …

Feature Extraction Through K-Means Segmentation For Melanoma Detection, Snigdha Priya Bommadevara

Masters Theses

"Malignant melanoma is responsible for 75% of the deaths caused due to skin cancer annually. However, melanoma detection can be possible through feature extraction and pattern classification, which can lower the risk, if the melanoma is detected at an early stage. Clustering is one of the most useful tools used to differentiate features that can contribute to melanoma. This research work uses the k-means clustering algorithm for implementation of color segmentation. However, k-means clustering requires a predefined value of k, i.e., the number of clusters must be specified at the beginning of the run. This research uses a predefined value …

Development Of Marker-Based Human Motion Capture Systems For Assembly Simulation And Ergonomic Analysis, Sajeev C. Puthenveetil

Masters Theses

"In aerospace industry, the assembly operator is often exposed to potential ergonomic injuries due to awkward postures while working in confined spaces. Manually generating worker postures in simulation software for ergonomic analysis is cumbersome. This research focuses on the use of marker-based optical motion capture technology to generate human motion simulations in real-time for ergonomic analysis. To address the challenges involved in capturing human motions in a real work environment, an assembly operation was simulated in a four-walled Computer Automated Virtual Environment (CAVE) which provides an immersive 3D environment to the worker performing the assembly operation. Multiple cameras were set-up …

High Temperature Sensor Based On Fabry-Perot Interferometer In Ceramic Coaxial Cable, Kenneth Paul Smith Jr.

Masters Theses

"In this thesis, the application of a coaxial cable Fabry-Perot interferometer (CCFPI) as a high temperature sensor is analyzed. Coaxial cable sensors provide the advantages of fiber optic sensors, such as the ability to be embedded and multiplexed, while overcoming the limitations created by the fragility of fibers. The fabrication process of the CCFPI, using a computer controlled drill system to create holes in the cable is discussed. By analyzing the amplitudes of the created reflections, the diameter of the holes is optimized. A new fabrication process, in which holes are drilled 180⁰ apart from each other to create a …

Manufacturing And Performance Evaluation Of Out-Of-Autoclave Sandwich Composites, Sriram Nagarajan

Masters Theses

"Composite sandwich structures are being increasingly employed in applications which require high strength, high in-plane and flexural stiffness coupled with a reduction in weight. Sandwich composites used in the aerospace industry are typically manufactured using high pressure autoclave processing which is expensive and time consuming. A viable low cost alternative is the Out-of-autoclave (OOA) process. One of the most dominant failure modes in sandwich composites is the debonding that occurs at the facesheet skin to core interphase leading to severe degradation of structural properties of the sandwich. A well formed adhesive bond at the skin to core interphase and improved …

Enhancement Of Vortex Induced Vibrations Using Roughness Strips, Ashwin Vinod

Masters Theses

"The current experimental work focuses on studying the effects of surface roughness on vortex induced vibration (VIV) of an elastically mounted circular cylinder which is free to vibrate in a direction transverse to the flow. Flow separation in known to occur due to viscous effects when a fluid flows over a bluff body. The separation of fluid causes shedding of alternating vortices in the downstream region, which in turn impart an alternating force on the bluff body. The vibrations incurred due to such forces are called as Vortex Induced Vibrations (VIV) and have been traditionally known to be harmful to …

Systems And Image Database Resources For Uav Search And Rescue Applications, David Christopher Macke Jr.

Masters Theses

"Aerial search and rescue applications using unmanned aerial vehicles (UAVs) can incorporate image processing technologies to locate targets faster and with a higher degree of accuracy. The task of developing such systems involves the development of both hardware and software components. Examples of both hardware and software approaches in the design process for an aerial imaging system are shown for small UAV applications. This project contains resources to help facilitate the incorporation of UAV applications into educational ventures and design projects. A power supply design is done for a lightweight imaging system and a large database of aerial images is …

Statistical Analysis Of Microarray Data In Sleep Deprivation, Stephanie Marie Berhorst

Masters Theses

"Microarray technology is a useful tool for studying the expression levels of thousands of genes or exons within a single experiment. Data from microarray experiments present many challenges for researchers since costly resources often limit the experimenter to small sample sizes and large amounts of data are generated. The researcher must carefully consider the appropriate statistical analysis to use that aligns with the experimental design employed. In this work, statistical issues are investigated and addressed for a microarray experiment that examines how expression levels change over time as individuals are sleep deprived. Over the course of 48 hours of sleep …

Field Performance Of Alternative And Cost Efficient Cast In Place And Precast Prestressed Concrete Bridge Approach Slabs, Nathan Price Muncy

Masters Theses

"In December of 2010, the Missouri Department of Transportation (MoDOT) investigated alternative cost-efficient bridge approach slabs (BASs). New BAS designs were subsequently developed and had a projected cost savings up to twenty-four percent with anticipated equal or better structural performance. A precast-prestressed (PCPS) BAS was introduced as an alternative to traditional BASs that offers advantages such as rapid construction and improved long-term durability. The three new BAS designs were implemented into in-situ bridge projects by MoDOT and the field performance was evaluated within this research study.

Field testing of each BAS was performed using two MoDOT HS20 trucks. Various instrumentation …

Part I: Increased Leaching Of Arsenic, Selenium, Molybdenum, And Vanadium From High Calcium Coal Ash Containing Trona Reaction Products. Part Ii: Using Agricultural Byproduct Rice Hull As Biosorbent To Remove And Recover Metal Ions In Water, Yongbo Dan

Masters Theses

"Part I. The trona is being injected to control SO_x emission from coal-fired power plants. The results showed that trona ash leached significantly more As, Se, Mo, and V than the control fly ash did, especially under the natural pH condition. In addition, trona ash had a significantly greater soluble fraction than the control ash. Further investigation indicated that greater amounts of the studied anionic elements in the trona ash were associated with the soluble, trona reaction products. Moreover, the insoluble fraction of the trona ash lost its capability to adsorb these elements under the natural pH condition. The …

Uterine Cervical Cancer Histology Image Feature Extraction And Classification, Cheng Lu

Masters Theses

"Cervical cancer, the second most common cancer affecting women worldwide and the most common in developing countries can be cured in almost all patients, if detected early and treated. However, cervical cancer incidence and mortality remain high in resource-poor regions, where early detection systems often cannot be maintained because of inherent complexity. The National Cancer Institute (NCI) has collected a vast amount of visual information, 100,000 cervigrams (35 mm color slides), screening thousands of women by this technique. In addition to the cervigrams, large digitized histology images are being archived.

In this research, a framework for automatic recognition and classification …

Development Of A Postprocessor For A Multi-Axis Cnc Milling Center, Mihir Satish Adivarekar

Masters Theses

"Most of the current college design and manufacturing curricula are primarily focused on computer aided design (CAD), while less emphasis is given to computer aided manufacturing (CAM). A great opportunity has been missed as the benefits of CAD/CAM cannot then be fully learned. Postprocessor plays a vital role in integration of CAD//CAM with computer numerically controlled (CNC) machines. Hence, postprocessor must be developed accurately. This thesis is composed of one paper. Paper I proposes a novel methodology to determine compensation vectors for the post processor of multi-axis milling center. The new approach that has been implemented in Paper I involves …