Engineering Commons^™

Poroelastic Finite Element Analysis Of A Heterogeneous Articular Cartilage Explant Under Dynamic Compression In Abaqus, Kelsey Kiyo Kam

Master's Theses

A poroelastic finite element model of a heterogeneous articular cartilage disc was

created to examine the tissue response to low amplitude (± 2% strain), low

frequency (0.1 Hz) dynamic unconfined compression (UCC). A strong correlation

has been made between the relative fluid velocity and stimulation of

glycosaminoglycan synthesis. A contour plot of the model shows the relative fluid

velocity during compression exceeds a trigger value of 0.25 μm/s at the radial

periphery. Dynamic UCC biochemical results have also reported a higher

glycosaminoglycan content in this region versus that of day 0 specimens. Fluid

velocity was also found not to be …

Photovoltaic Emulator Adaptable To Irradiance, Temperature And Panel Specific I-V Curves, Joseph Gamos Durago

Master's Theses

This thesis analyzes the design and performance of a photovoltaic (PV) emulator. With increasing interest in renewable energies, large amounts of money and effort are being put into research and development for photovoltaic systems. The larger interest in PV systems has increased demand for appropriate equipment with which to test PV systems.

A photovoltaic emulator is a power supply with similar current and voltage characteristics as a PV panel. This work uses an existing power supply which is manipulated via Labview to emulate a photovoltaic panel. The emulator calculates a current-voltage (I-V) curve based on the user specified parameters of …

A Pmma Conductivity Pretreatment Microfluidics Device For The Optimization Of Electrokinetic Manipulations, Cameron Paul Purcell

Master's Theses

This project encompasses the design and development of a pretreatment microfluidic device for samples of physiological conductivity, namely a saline solution. The conductivity was reduced through the combination of dilution and ion removal using electric fields to enable downstream electro kinetic manipulations. The two major parts of this project include (1) designing a pretreatment protocol to reduce the conductivity of the sample solution to an acceptable level and (2) designing /fabricating a microchip that will effectively allow aim (1) to be performed on chip.

This project is one of the first to observe the effects of an electric field, used …

Designing The Human-Powered Helicopter: A New Perspective, Gregory Hamilton Gradwell

Master's Theses

The concept of human-powered vertical flight was studied in great depth. Through the manipulation of preexisting theory and analytical methods, a collection of design tools was created to expediently conceptualize and then analyze virtually any rotor. The tools were then arranged as part of a complete helicopter rotor design process. The lessons learned as a result of studying this process—and the tools of which it consists—are presented in the following discussion. It is the belief of the author that by utilizing these tools, as well as the suggestions that accompany them, future engineers may someday build a human-powered helicopter capable …

Rfid Classroom Management System, Andrew W. Wright

Master's Theses

Professors who manage large classes are unrealistically expected to grade each student fairly and accurately.  Even with all of the technological advancements that have occurred in the past thirty years, very little progress has been made in classroom management, and as a result, professors are not equipped with enough tools to successfully manage large class sizes.  Because radio frequency identification (RFID) technology is making its way into student issued identification cards, there is an opportunity to use it as a tool to aid professors in the classroom.  The focus of this paper is to discover the most effective system that …

Adaptive Component Usage For The Thermal Management Of Picosatellites, William D. Whalen

Master's Theses

The CubeSat standard originated in 1999.  It was a joint development led by Dr. Jordi Puig-Suari of California State Polytechnic University San Luis Obispo and Professor Robert Twiggs of Stanford University. The engineering challenges that have come from this picosatellite class have created incredible educational opportunities for engineering students throughout the world.  Since the challenges of engineering a CubeSat abound the designers are always looking at novel and even revolutionary solutions to each one.  One of those opportunities is in thermal subsystem design, implementation and characterization.  A potential solution for CubeSats is adaptive component usage.

This thesis is the written …

Low Cycle Fatigue Behavior Of Concrete With Recycled Concrete Aggregates, Paul Mark Gordon

Master's Theses

A comparison of concrete containing recycled concrete coarse aggregates and natural coarse aggregates subjected to high strain, low cycle compressive fatigue is presented. Using a strain based feedback control loop, concrete cylinders are compressed at 15µε/s to a specified strain then unloaded to zero stress for 10 cycles. After cycling, all samples are loaded to a strain of 0.008. Direct concrete material variables are the water to cement (w/c) ratio, taken as 0.60, 0.45, and 0.39, and percent coarse recycled concrete aggregate content, varied from zero to 100 percent. The primary testing variable is the specified unloading strain. Unloading strains …

Development Of An Open Source Prosthetic Hand Platform, Scott James Garrett

Master's Theses

Development of an Open Source Prosthetic Hand Platform

Scott Garrett

In the field of upper extremity prosthetic devices, advancements in technology drive the design of products which are becoming capable of restoring the lost functions of the native hand. While several dexterous devices have been developed to serve this purpose, they remain prohibitively expensive and thus are not a viable option for many upper extremity amputees. To address this problem a prosthetic hand platform was developed utilizing the open source Arduino microcontroller and off-the-shelf electrical components. Using these resources, a novel finger actuation mechanism was developed to show how …

The Effectiveness Of Milestone Versus Duration Projects In A University Environment, Nicholas James Mehas

Master's Theses

The Critical Path and Critical Chain project management methodologies have different and unique characteristics; both methods are used by project managers to manage projects. This research develops and implements two methodologies, milestones (critical path) versus duration (modified critical chain), in a university environment. The implementation of the two methods allows for the comparison of the effectiveness of both styles. The intent is to determine if there is a significant difference in the project management methodologies in a university setting. The design of both projects allows for easy implementation and the ability to easily record determined measureable statistics.

Anaerobic Co-Digestion Of Microalgae With Food Waste And Wastewater Sludge, Ruth E. Spierling

Master's Theses

This research sought to optimize anaerobic co-digestion of microalgae biomass harvested from a wastewater treatment pond facility with locally-available wastes.  The goal was to produce high methane yields and stable digestion without the need for supplemental alkalinity addition.  A key research question was if algae digestion could be improved via the synergistic effects of co-digestion.  Cell disruption to increase digestibility was not pursued due to its relatively high mechanical complexity and high energy use.  For the wastewater treatment ponds studied, the most practical co-substrates identified were municipal wastewater sludge and food waste (sorted organic municipal waste).  Although wastewater sludge does …

Studying Milk Coagulation Kinetics With Laser Scanning Confocal Microscopy, Image Processing, And Computational Modeling, Richard Joseph Hennessy

Master's Theses

The kinetics of milk coagulation are complex and still not well understood. A deeper understanding of coagulation and the impact of the relevant factors would aid in both cheese manufacturing and also in determining the nutritional benefits of dairy products. A method using confocal microscopy was developed to follow the movement of milk fat globules and the formation of a milk protein network during the enzyme-induced coagulation of milk. Image processing methods were then used to quantify the rate of coagulation. It was found that the texture of the protein network is an indicator of the current status of the …

Characterization And Implementation Of A Decellularized Porcine Vessel As A Biologic Scaffold For A Blood Vessel Mimic, Aubrey N. Smith

Master's Theses

Every 34 seconds, someone in the United States suffers from a heart attack.  Most heart attacks are caused by atherosclerotic build up in the coronary arteries, occluding normal blood flow.  Balloon angioplasty procedures in combination with a metal stent often result in successful restoration of normal blood flow.  However, bare metal stents often lead to restenosis and other complications.  To compensate for this problem, industry has created drug-eluting stents to promote healing of the artery wall post stenting.  These stents are continually advancing toward better drug-eluting designs and methods, resulting in a need for fast and reliable pre-clinical testing modalities. …

Implementation And Assessment Of Hyperglycemic Conditions For The Creation Of A Diabetic Blood Vessel Mimic, Vikramaditya Mediratta

Master's Theses

Introduction: Diabetes Mellitus is a metabolic disorder that affects a person’s ability to either produce insulin (Type I diabetes mellitus) or properly use insulin (Type II diabetes mellitus) in order to maintain adequate blood glucose levels. The most severe diabetic complications arise due to hyperglycemia – a state of extremely high blood glucose levels – such as, coronary artery disease (CAD), in which coronary stent therapy is a popular method of treatment. However, research has shown a high rate of in-stent restenosis in diabetic patients with CAD, most likely due to activation of cellular adhesion molecules on endothelial cells exposed …

An Optimization Approach To Employee Scheduling Using Fuzzy Logic, William G. Spence

Master's Theses

An Optimization Approach to Employee Scheduling Using Fuzzy Logic

William G. Spence

Selection of sales employees is critical because the sales employees represent the company’s image, competitive advantage, technology, and values. In many service systems the majority of consumer contact is with the sales department. Since there are different types of customers, scheduling quality salespersons who can adequately help consumers may affect revenue.

This thesis proposes a new methodology for the scheduling of employees in a service system. The methodology uses Fuzzy Logic to calculate possible sales and Linear Programming to create an optimal schedule. This approach enables the rating …

Underwater Localization And Tracking Of Physical Systems, Patrick E. Carroll

Master's Theses

In this paper, we investigate the problem of localizing an underwater sensor node basedon message broadcasting from multiple surface nodes. With the time-of-arrival measurementsfrom a DSP-based multicarrier modem, each sensor node localizes itself based on the traveltime differences among multiple senders to the receiver. Using one-way message passing, such asolution can scale to accommodate a large number of nodes in a network. We consider the issuefrom not only the physical layer, but also at the node processing layer by incorporating a trackingsolution. We present simulation results as well as preliminary testing results in a swimming poolwith both stationary and moving …

Rate-Dependent Behavior Of Clay, Harry F. Martindale Iv

Master's Theses

This thesis presents a strain-rate dependent two-surface plasticity constitutive model for clays based on the critical-state soil mechanics.  The model reproduces the mechanical response of clays under multi-axial loading conditions and predicts both drained and undrained behaviors at small and large strains.  Model parameter values are determined for Boston Blue Clay, London Clay and Kaolin Clay.  The performance of the model in simulating the mechanical response of clays is demonstrated for a variety of strain rates. Sensitivity of each model parameter is checked for ±5, ±10 and ±20% of the deterministic values. Probabilistic analysis using Monte Carlo simulations were done …

Noninvasive Assessment Of Joint Motion Over Long Durations: System Evaluation And Data Analysis Methods, Maria J. Qadri

Master's Theses

The development, progression, and treatment of degenerative musculoskeletal diseases, such as carpal tunnel and shoulder impingement syndromes, may be better characterized when joint motions are assessed over long durations outside clinical, laboratory, or rehabilitation settings that involve standardized assessment, exercise protocols, and/or regimented movements. Assessment methods for human movement capture beyond laboratory or clinical experiments are typically limited to short capture times of less than one hour. Noninvasive, long-duration measurements of joint motion in occupational settings provides more insight into movement patterns and quantitative assessments regarding joint usage, which lead to a better understanding of the cumulative effects associated with …

Finite Element Analysis Of The Effect Of Low-Speed Rear End Collisions On The Medial Meniscus, Daniel J. Tichon

Master's Theses

Low-speed, rear end vehicle collisions can inflict soft tissue damage to the passenger’s knees, especially the medial meniscus, which has been previously unexplained in published literature.  It is difficult to determine if factors such as age or other injury was the primary cause of the injury or if the accident acutely caused the meniscal tear.  Rear end collisions may produce a combination of compressive loading and torque about the knee that will injure the medial meniscus during the initial impact and the rebound phase.  The purpose of this study is to determine if it is possible for rear end low-speed …

Public Transit Accessibility And Need Indices: Approaches For Measuring Service Gap, Sha Mamun

Master's Theses

The integration of transit needs into transit accessibility indexing is important for the evaluation of existing transportation systems and, service gaps, and for the identification of priority areas for future investments in transportation infrastructure. This thesis details an accessibility-based transit need indexing model that focuses on the necessity of evaluating transit needs and transit accessibility simultaneously. A need index is developed to identify areas in high need of public transit services using economic and socio-demographic information and a composite accessibility index is developed to identify levels of access to transit services and shortcomings in service provision. The need for transit …

Public Perception Of Public Transportation And Its Built Environment In The New Haven - Springfield Corridor, Garrett S. Bolella

Master's Theses

Studying and quantifying public perception of public transportation and the built environment in which it operates is crucial to understanding the symbiotic relationship between transportation and land use. This paper presents a choice experiment which places respondents into personalized hypothetical scenarios and examines their preferences for new transit service and the environment in which it operates. The choice experiment survey instrument investigates public response to hypothetical bond referenda to fund new transit projects with particular service and built environment attributes. Service options are characterized by six attributes: service type, service reliability, comfort, stop environment, parking availability at final destination, and …

Development & Application Of The Transportation Index For Sustainable Places (Tisp), Jason Zheng

Master's Theses

The purpose of transportation systems go beyond the movement of people and goods. These systems shape the natural and built environment which subsequently affects social and economic interactions. However, conventional metrics typically only address the mobility aspect of transportation via measures such as level of service and congestion. Metrics are needed to evaluate the broader impacts of transportation.

This work describes the Transportation Index for Sustainable Places (TISP), a performance metric designed to assess the sustainability of transportation systems with respect to environmental, social, and economic outcomes. The development of the TISP was guided through literature review focused on understanding …

The Impacts Of Road Capacity Removal, Jason E. Billings

Master's Theses

The road infrastructure of North America is aging, and many governments are faced with a critical decision:  do we repair or remove freeways from our urban centers?  Freeway repair is exceptionally expensive, but removing a freeway is widely seen as a risky venture which may result in negative traffic effects.  Therefore, it is necessary to gain a clearer understanding of how removing road capacity effects traffic distribution.  Three freeway segments were ultimately selected for case study analysis: two in San Francisco and one in Milwaukee.  This analysis consisted of identifying changes in the traffic volumes and volume-capacity (V/C) ratios in …

Comprehensive Analysis Of Effluent Organic Matter From Five Wastewater Treatment Plants In Connecticut And Comparison To Natural Organic Matter, Matthew L. Quaranta

Master's Theses

Natural organic matter is an important driver of biotic and abiotic processes in aquatic environments. Wastewater treatment plants discharge a substantial amount of organic matter into the environment; however effluent organic matter has not been well studied. In this study, traditional organic geochemical techniques were applied to characterize effluent organic matter. Effluent organic matter was isolated by DAX8 (hydrophobic fraction) and XAD4 (transphilic fraction) Amberlite resins. Extraction efficiencies of effluent organic matter by DAX8 resins ranged from 18 to 42 percent as a result of larger content of hydrophilic organic matter than natural organic matter. Average organic matter molecular weights …

A Comparative Study Of Total Hemoglobin Measurement Technology: Noninvasive Pulse Co-Oximetry And Conventional Methods, Jared S. Ruckman

Master's Theses

Hemoglobin can be measured on a variety of devices using different principles of operation. Noninvasive pulse CO-oximetry represents the latest development in hemoglobin measuring technology. The technology uses principles similar to pulse oximetry to measure total hemoglobin, oxyhemoglobin, reduced oxyhemoglobin, carboxyhemoglobin and methemoglobin. Similar to the introduction of pulse oximetry to the medical field, pulse CO-oximetry has been met with skepticism. Since the technology is noninvasive and provides continuous monitoring in comparison to invasive and discrete techniques used in other methods, CO-oximetry purportedly provides an advantage in patient care. The purpose of this research is threefold: (a) to review the …

The Use Of Motion Analysis Technology As An Alternative Means Of Assessing Spinal Deformity In Patients With Adolescent Idiopathic Scoliosis, Matthew J. Solomito

Master's Theses

Adolescent Idiopathic Scoliosis (AIS) is a three dimensional deformity of the spine that causes abnormal curvatures in the coronal and sagittal planes and abnormal vertebral rotations. The gold standard for diagnosing and tracking the progression of the deformity is through the use of repeated radiography and a patient can receive upwards of fifteen radiographic series over the course of treatment, which exposes this population to an increased risk of radiation-dependent complications.

This thesis presents the necessary calculations and the marker set required to make the motion capture technology a viable alternative to radiographs, in an effort to reduce the patient’s …

Design Of A Pragmatic Test Lab For Evaluating And Testing Wireless Medical Devices For Deployment On An Integrated It Wireless Network, Allie Paquette

Master's Theses

In today’s healthcare environment, networking of medical devices is becoming more and more prevalent. There is an increasing need for mobile technology to meet clinical needs. Wireless communication is essential for allowing medical devices to be able to move with the patient, while continuing to record and communicate patient data. A traditional example is telemetry monitoring, but other examples of wireless utilization include sending ECG test results to the EMR or remotely updating the drug library on numerous IV pumps. Each wireless application has varying demands on the connectivity infrastructure and will share radio frequency (RF) spectrum resources with a …

Characterization And Implementation Of Low Intensity Pulsed Ultrasound As A Tool To Apply Physical Load To Scaffolds And Bone Cells For Fracture Repair, Scott Frazee

Master's Theses

One current challenge in treating bone fractures is the effective treatment of non-unions and delayed unions. Low Intensity Pulsed Ultrasound (LIPUS) has been approved by the FDA to treat fresh fractures since 1994 and non-unions since 2000 and is an attractive treatment option because it is non-invasive. The mechanism by which it works, however, is not well understood; what is known is largely confined to the resultant changes in chemical output of cells. In this thesis several concepts and techniques were brought together to investigate the following hypothesis: LIPUS produces a measurable physical load that results in measurable deformation and …

Residual Strength Of Ultra-High Performance Concrete After Exposure To Elevated Temperatures, Brian T. Burke

Master's Theses

This paper presents the results of a study on the effect of elevated temperatures on the compressive strength of ultra-high-performance fiber-reinforced concrete (UHPFRC). Two different mixtures of a commercially available UHPFRC were considered in this study. The standard mixture offered by the manufacturer incorporates only steel-fibers to improve the tensile properties of the concrete. The enhanced mixture, which is of primary focus in the study, incorporates additional polypropylene fibers to improve the fire-resistance behavior. Specimens from each mixture were cast into 76 mm (3 in.) diameter cylinders and 51 mm (2 in.) cubes. After exposure to elevated temperatures …

Interoperation For Lazy And Eager Evaluation, William Jeffrey Faught

Master's Theses

Programmers forgo existing solutions to problems in other programming lan- guages where software interoperation proves too cumbersome; they remake so- lutions, rather than reuse them. To facilitate reuse, interoperation must resolve language incompatibilities transparently. To address part of this problem, we present a model of computation that resolves incompatible lazy and eager eval- uation strategies using dual notions of evaluation contexts and values to mirror the lazy evaluation strategy in the eager one. This method could be extended to resolve incompatible evaluation strategies for any pair of languages with common expressions.

Mammary Epithelial Cell Growth On A Three-Dimensional Scaffold In An Operating Bioreactor, Melissa Marie Davalle

Master's Theses

Mammary epithelial cells are highly efficient secreting cells. With genetic engineering, the uses of these cells could be endless. Research is being conducted on these cells to determine their full potential to the biotech industry.

This paper investigates whether bovine epithelial mammary cells can survive in glutaraldehyde-treated gelatin tubes in an operating bioreactor. Many bioreactors were developed and tested to suit the needs of the cells. Procedures were created and carried out to ensure sterility of the bioreactors. Bovine mammary epithelial cells were implanted in the bioreactors and samples of their growth were taken over time.