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Full-Text Articles in Engineering

Evaluation Of Shiryaev-Roberts Procedure For On-Line Environmental Radiation Monitoring, Mara Watson Aug 2015

Evaluation Of Shiryaev-Roberts Procedure For On-Line Environmental Radiation Monitoring, Mara Watson

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An on-line radiation monitoring system that simultaneously concentrates and detects radioactivity is needed to detect an accidental leakage from a nuclear waste disposal facility or clandestine nuclear activity. Previous studies have shown that classical control chart methods can be applied to on-line radiation monitoring data to quickly detect these events as they occur; however, Bayesian control chart methods were not included in these studies. This work will evaluate the performance of a Bayesian control chart method, the Shiryaev-Roberts (SR) procedure, compared to classical control chart methods, Shewhart 3-σ and cumulative sum (CUSUM), for use in on-line radiation monitoring of 99Tc …

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Comparison Gmm And Svm Classifier For Automatic Speaker Verification, Shamama Afnan Aug 2015

Comparison Gmm And Svm Classifier For Automatic Speaker Verification, Shamama Afnan

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The objective of this thesis is to develop automatic text-independent speaker verification systems using unconstrained telephone conversational speech. We began by performing a Gaussian Mixture Model Likelihood ratio verification task in speaker independent system as described by MIT Lincoln Lab. We next introduced a speaker dependent verification system based on speaker dependent thresholds. We then implemented the same system applying Support Vector Machine. In SVM, we used polynomial kernels and radial basis function kernels and compared the performance. For training and testing the system, we used low-level spectral features. Finally, we provided a performance assessment of these systems using the …

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Bioprinting As A Tool To Evaluate Interactions Of Cancerous And Noncancerous Cells, Holly Jordan Aug 2015

Bioprinting As A Tool To Evaluate Interactions Of Cancerous And Noncancerous Cells, Holly Jordan

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Cancer is becoming one the leading causes of death worldwide, and in particular, breast cancer, which is the second highest cause of cancer death for women. Approximately 12 percent of US women will develop invasive breast cancer, and about 40,000 of US women will die from breast cancer in 2015. With better detection and treatment options, breast cancer death has been decreasing over the past two decades. Despite declining rates in breast cancer death, cancer progression is not well understood. There are many studies focused on cancer, but in situ cancer studies are often hard to reproduce and can even …

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Microcosm Evaluation Of Enhanced Bioremediation For An Industrial Site Contaminated With Chlorinated Ethenes, Chlorinated Benzenes, And Benzene, Christopher Moss Aug 2015

Microcosm Evaluation Of Enhanced Bioremediation For An Industrial Site Contaminated With Chlorinated Ethenes, Chlorinated Benzenes, And Benzene, Christopher Moss

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Groundwater contaminants at an industrial site in South Carolina include tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2-dichloroethene (cDCE), vinyl chloride (VC), 1,2,4-trichlorobenzene (1,2,4-TCB), 1,2-dichlorobenzene (1,2-DCB), 1,4-dichlorobenzene (1,4-DCB), chlorobenzene (CB), and benzene. The source areas at the site include a tank farm area, a grease trap area, the former wastewater lagoons (WWTP) and the former oil retention pond (ORP). A microcosm evaluation was preformed to determine the potential for bioremediation to treat the organic contaminants in the four source areas (within the saturated zone) and in a downgradient portion of the groundwater plume. The objectives were to evaluate 1) anaerobic treatment at the …

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Using Connected Vehicle Technology To Implement A Pay For Priority System At Signalized Intersections, Melissa Gende Aug 2015

Using Connected Vehicle Technology To Implement A Pay For Priority System At Signalized Intersections, Melissa Gende

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This research evaluated a mixed vehicle environment that included connected and non-connected vehicles in which connected vehicles (CV) were allowed to pay a small fee to request priority at a signalized intersection, similar to a transit signal priority system. Connected vehicles with signal priority were simulated with penetration levels ranging from 10% to 100% as well as with various priority directions (all directions, major street movements in both directions, and major street movements in the direction of highest flow) being allowed to request priority. These scenarios were compared to optimized signal timings to determine the effectiveness of the technology in …

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Biodegradation Of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) Using Photosynthetic Bacteria, Sarah Galloway Aug 2015

Biodegradation Of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) Using Photosynthetic Bacteria, Sarah Galloway

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Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is an emerging contaminant according to the Environmental Protection Agency (EPA). RDX was introduced as a secondary explosive during World War II. It is still used in many explosive such as hand grenades. RDX enters the environment mostly through the manufacturing process or from the use of explosives. RDX is a suspected carcinogen and can also affect the nervous system of humans. Therefore, RDX has become a chemical of concern across many United States military bases and open and closed manufacturing plants. The goal of this research was to evaluate the biodegradation of RDX via two phototrophic bacteria: …

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Microcosm Study Of 1,4-Dioxane Biotransformation, Philip Arve Jul 2015

Microcosm Study Of 1,4-Dioxane Biotransformation, Philip Arve

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1,4-Dioxane is an emerging groundwater contaminant and probable human carcinogen with considerable potential remediation costs due to its hydrophilic and recalcitrant nature. Commonly occurring with 1,1,1-trichloroethane (1,1,1-TCA) plumes due to its application as a solvent stabilizer, 1,4-dioxane is also used in industrial lubricants and occurs as an impurity in numerous personal care products. Current treatment strategies to treat dioxane contamination include advanced oxidation processes and biological treatment, though only aerobic paths of biodegradation are currently understood. Laboratory and field studies have indicated the possible inhibitory effects of 1,1,1-TCA and its abiotically transformed daughter product, 1,1-dichloroethene (1,1-DCE) on the aerobic biodegradation …

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Estimation Of Pcb Contamination In The Twelve Mile Creek Arm Of Lake Hartwell Using Gis And Statistical Techniques, Arjun Bharadwaj Jun 2015

Estimation Of Pcb Contamination In The Twelve Mile Creek Arm Of Lake Hartwell Using Gis And Statistical Techniques, Arjun Bharadwaj

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The Lake Hartwell and its Twelve Mile Creek watershed were contaminated with polychlorinated biphenyls (PCBs), mainly Aroclor 1016 and 1254, which resulted in a designation as a Superfund site. The Twelve Mile Creek arm is the most heavily contaminated portion of the lake. The Twelve Mile Creek arm of Lake Hartwell was placed on the National Priorities List (NPL) in the year 1990. In the Record of Decision (ROD) by the EPA in 1994, natural attenuation, primarily through burial by uncontaminated sediment, was declared as the chosen remedy to reach the EPA recommended level of 1 µg/g. Several studies have …

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A Method For The Characterization And Selection Of Compliant Joints, Ronald George Saleeby May 2015

A Method For The Characterization And Selection Of Compliant Joints, Ronald George Saleeby

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A compliant joint is a connection between two bodies that derives its movement from the deflection of flexible members rather than rigid connections, like traditional joints. Compliant joints have potential advantages that include longer part life, reduction of parts in assemblies, and reduced wear. Traditional compliant mechanism design methodologies have limitations involving the burden of necessary knowledge required to satisfactorily use them. The method presented in this thesis was developed to provide compliant joint design solutions independent of the traditional methods of compliant joint design by allowing the selection of compliant joints from a repository. The repository is populated by …

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Continuum Robots For Space Applications Based On Layer-Jamming Scales With Stiffness Capability, Jessie Lee C. Santiago May 2015

Continuum Robots For Space Applications Based On Layer-Jamming Scales With Stiffness Capability, Jessie Lee C. Santiago

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Continuum robots, which have continuous mechanical structures comparable to the flexibility in elephant trunks and octopus arms, have been primarily geared toward the medical and defense communities. In space, however, NASA projects these robots to have a place in irregular inspection routines. The inherent compliance and bending of these continuum arms are especially suitable for inspection in obstructed spaces to ensure proper equipment functionality. In this paper, we propose a new solution that improves on the functionality of previous continuum robots, via a novel mechanical scaly layer-jamming design. Layer-jamming assisted continuum arms have previously required pneumatic sources for actuation, which …

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Engineering Hospital Discharge Instructions: An Eye-Tracking Based Study, Haley Marie Vaigneur May 2015

Engineering Hospital Discharge Instructions: An Eye-Tracking Based Study, Haley Marie Vaigneur

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With new healthcare reform initiatives, (e.g., the Patient Protection and Affordable Care Act) hospitals have additional requirements to reduce avoidable readmissions. This results in identifying the needs for improving the hospital discharge process, improving care transitions and discharge instructions, and increasing overall patient health literacy. In terms of discharge instructions, one of the most influential factors to patients' understanding and compliance with their prescribed health regimen is the document's readability. The study goal is to examine how adjusting the discharge instructions' reading level and using human factors design guidelines can influence a novice user's ability to read, comprehend, and recall …

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Assessment Of Bore-Cone Taper Junctions In Explanted Modular Total Hip Replacements, Christine Margaret Stamer May 2015

Assessment Of Bore-Cone Taper Junctions In Explanted Modular Total Hip Replacements, Christine Margaret Stamer

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For people with chronic hip pain due to arthritis or other conditions, a total hip replacement (THR) is a common procedure used to eliminate the pain. Due to the natural variation in patient anatomy, THR prostheses are becoming increasingly more modular to allow for a more customized initial replacement and for an easier revision if needed in the future. Currently, THR prostheses routinely have modular femoral heads to provide surgeons with intraoperative flexibility. This modularity allows the surgeons to maintain the proper leg length and restore hip biomechanics for the patient and insert the components more easily and precisely. Modular …

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Computational Modeling Of Alternating Current Potential Drop Measurement For Crack Detection Of Multi-Functional Ceramic Coated Structures, Simha Sandeep Rao May 2015

Computational Modeling Of Alternating Current Potential Drop Measurement For Crack Detection Of Multi-Functional Ceramic Coated Structures, Simha Sandeep Rao

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Non-destructive testing and evaluation (NDT&E) is a set of techniques commonly used to evaluate a material for the presence of any flaws without actually degrading the material itself. The Alternating Current Potential Drop (ACPD) test method is one of the NDT surface methods used to determine the electrically insulating defects beneath the surface by injection of currents in the structure and measurement of the resulting voltage difference between two or more points on the surface. The presence of defects generally increases the resistance of the structure and hence causes the drop of measured voltage. The inversion of this data can …

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Benefits Of A State Driveway Database With Qualitative And Quantitative Crash Analysis, Andrew Bryant Stokes May 2015

Benefits Of A State Driveway Database With Qualitative And Quantitative Crash Analysis, Andrew Bryant Stokes

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The primary goal of this research is to show how a fully developed driveway database will improve access management practices resulting in a reduction in crashes, injuries, and fatalities on our roadways. The results of this thesis highlight a close relationship between driveway characteristics and the incidence of crashes. Thus, it is critical to be proactive in enforcing access management strategies and policies that are designed to enhance driveway safety without compromising the economic vitality of land use along roads. The analysis identified several significant independent variables that influence crash rates either positively or negatively. The data driven approach to …

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Eye Tracking Consumer Purchase Behavior Within Physical And Virtual Environments, David Andrew Stone May 2015

Eye Tracking Consumer Purchase Behavior Within Physical And Virtual Environments, David Andrew Stone

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Understanding how consumers observe and make purchase decisions within a retail context is now both accessible and efficient through the process of eye tracking. Eye tracking package design aesthetics helps us understand and predict what consumers are looking at, and how likely a package might be selected. Typically, this research is conducted in an immersive retail setting where consumers can shop as they would in a normal store-shopping context. A store is stocked with products where a participant in the study shops throughout while wearing an eye tracker to gather data on what their attention fixates on within a given …

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Endothelialization Using Protein Substrates And Hydrogels For Aortic Valve Applications, Elizabeth A. Fontaine May 2015

Endothelialization Using Protein Substrates And Hydrogels For Aortic Valve Applications, Elizabeth A. Fontaine

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Aortic valve disease is currently the leading cause of cardiovascular morbidity in the United States.1 In 2003, approximately 290,000 patients required heart valve replacement and that number is estimated to continue to rise as the average age of the population continues to increase.2 However, the current valve replacement options have multiple limitations. Tissue engineering hopes to address these shortcomings by providing a viable valve that more closely mimics the native valve, structurally and functionally.3 An ideal valve replacement should contain endothelial and interstitial cells, with the ability to remodel the extra-cellular matrix. While tissue-engineered heart valves are not uncommon in …

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Bromide Removal From Surface Waters By Silver Impregnated Activated Carbon, Chen Chen Jan 2015

Bromide Removal From Surface Waters By Silver Impregnated Activated Carbon, Chen Chen

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Bromide is a precursor of disinfection by-products (DBPs) during potable water treatment, because it causes the formation of brominated DBPs that are more cyto- and geno-toxic than their chlorinated analogues. Due to the potential health risks of DBPs, the United States Environmental Protection Agency (USEPA) has been imposing increasingly stringent regulations for controlling the DBPs. Therefore, removal of bromide ions from source waters becomes critical for controlling the DBPs formation. In my study, it was hypothesized that silver impregnated activated carbon (SIAC) can be a promising adsorbent for bromide removal from water. The main research objectives of this study were …

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Scientific Application Acceleration Utilizing Heterogeneous Architectures, Edwin Weill Dec 2014

Scientific Application Acceleration Utilizing Heterogeneous Architectures, Edwin Weill

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Within the past decade, there have been substantial leaps in computer architectures to exploit the parallelism that is inherently present in many applications. The scientific community has benefited from the emergence of not only multi-core processors, but also other, less traditional architectures including general purpose graphical processing units (GPGPUs), field programmable gate arrays (FPGAs), and Intel's many integrated cores (MICs) architecture (i.e. Xeon Phi). The popularity of the GPGPU has increased rapidly because of their ability to perform massive amounts of parallel computation quickly and at low cost with an ease of programmability. Also, with the addition of high-level programming …

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Relationship Between Peel Force, Opening Force, And Burst Force For A Semi-Rigid Cup And Lid, Pre- And Post-Retort, Raj Navalakha Dec 2014

Relationship Between Peel Force, Opening Force, And Burst Force For A Semi-Rigid Cup And Lid, Pre- And Post-Retort, Raj Navalakha

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This research determines if there is any relationship between the peel force, the opening force and the burst force for a semi-rigid cup and lid system, for pre- and post-retort conditions. It also compares the relationship (regression lines) between these forces pre- and post-retort. These seal results were studied by varying the sealing parameters of dwell time and temperature while keeping the pressure constant. Polypropylene cups and a peelable barrier retort lidding were used in this study. As compared to past research, a different peel testing technique was used to measure the peel and the opening force. The entire lid …

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Microanalysis Of Polymer Chain Diffusion In Heat Seals, Russell Cooper Dec 2014

Microanalysis Of Polymer Chain Diffusion In Heat Seals, Russell Cooper

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Heat sealing is an integral method for the closure and protection of packaging. Previous work has shown that seal strength is developed by the interdiffusion of polymer chains within heat seals. Heat seals were made between two dissimilar materials. Poly(ethylene-co-acrylic acid) (EAA) was heat sealed to ionomer. Diffusion within the EAA-ionomer heat seals was estimated. The diffusion estimates were then related to resulting seal strength in the EAA-ionomer sealant system. Heated tooling sealing was utilized to make heat seals at 40 psi (275.79 kPa), 0.5 seconds, and a range of temperatures between 180˚F (82.22˚C) and 300˚F (148.89˚C). Scanning electron microscopy …

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Inlay Vs. Onlay: A Comparison Of Two Glenoid Systems In Total Shoulder Arthroplasty, Sarah Helms Dec 2014

Inlay Vs. Onlay: A Comparison Of Two Glenoid Systems In Total Shoulder Arthroplasty, Sarah Helms

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Loosening of the glenoid component via a 'rocking horse' phenomenon, whereby the glenoid loosens as a result of edge loading of the implant during mild off-axis motion, is a common complication of total shoulder arthroplasties (TSAs). Recently, a partial glenoid resurfacing implant, known as a glenoid inlay, has become available and due to its geometry has the potential to exhibit less rocking-horse loosening during humeral articulation than the standard glenoid onlay systems currently used in TSA. The inlay design is implanted centrally on the glenoid to match the surrounding anatomy with a fit that leaves it flush with the surrounding …

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The Effects Of Chlorine Dioxide Gas On The Sensory Properties Of Whole Tomatoes, Christopher Gottilla Dec 2014

The Effects Of Chlorine Dioxide Gas On The Sensory Properties Of Whole Tomatoes, Christopher Gottilla

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This experiment sought to measure the changes in sensory quality that occur in tomatoes as the result of chlorine dioxide gas treatment. Tasti-Lee tomatoes (VFFF Hybrid #5755) were treated with two different levels of chlorine dioxide gas (10mg and 50mg of ClO2-forming material per kg of tomato) utilizing sachets. Testing compared the treated tomatoes and an untreated control group. These tests included flat-plate compression for firmness, sensory evaluation using a difference from control test, color analysis of the skin and flesh using a colorimeter, and enumeration of aerobic microbes and yeasts and molds. Flat-plate compression of whole tomatoes revealed no …

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Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments, Amanda Macaluso Dec 2014

Characterization Of Biofilms On Medical Device Materials With Application To Reusable Surgical Instruments, Amanda Macaluso

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Reusable medical devices or reprocessed single-use devices are original medical devices that have been used once and then are cleaned, sterilized, and remanufactured for the purpose of an additional single use on a single patient [4]. Improperly reprocessed devices are a significant contributor to hospital-associated infections [4]. Challenges that hinder reprocessing are related to the complexity of reusable medical device design, the necessary validation of cleaning protocols required by the U.S Food and Drug Administration (FDA), the impact of human factors throughout the reprocessing cycle, as well as economic factors within new business models that are centered on reprocessing. Current …

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Design Of A Mobile Web-Based Dashboard To Improve Work Practices Of Crna Board Runners, Mahesh Sreedharan Dec 2014

Design Of A Mobile Web-Based Dashboard To Improve Work Practices Of Crna Board Runners, Mahesh Sreedharan

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Traditional artifacts such as whiteboards serve as key tools in helping healthcare professionals keep track of frequently changing information and managing their work schedule. The simplicity of these tools has made them easy to adopt into the work culture and since these artifacts are not usually electronic, they need no external technical support or maintenance. However, these artifacts present unique challenges to their users, the primary one being lack of mobility offered. The whiteboards are usually stationary and the users will have to assemble near them to update or gather information. In a hospital, this adds significant overhead to the …

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Design, Analysis And Implementation Of An Experimental System To Harvest Energy From Atmospheric Temperature Variations Using Ethyl Chloride Filled Bellows, Gibran Ali Dec 2014

Design, Analysis And Implementation Of An Experimental System To Harvest Energy From Atmospheric Temperature Variations Using Ethyl Chloride Filled Bellows, Gibran Ali

All Theses

The increase in global warming and the dwindling supplies of fossil fuels have shifted the focus from traditional to alternate sources of energy. This has resulted in a concerted effort towards finding new energy sources as well as better understanding traditional renewable energy sources such as wind and solar power. In addition to the shift in focus towards alternate energy, the last two decades have offered a dramatic rise in the use of digital technologies such as wireless sensor networks that require small but isolated power supplies. Energy harvesting, a method to gather energy from ambient sources including sunlight, vibrations, …

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A Study Of The Regularity Of Autocorrelation Of Manipulation Of Wrist Motion During Eating, Xueting Yu Dec 2014

A Study Of The Regularity Of Autocorrelation Of Manipulation Of Wrist Motion During Eating, Xueting Yu

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This thesis considers the problem of detecting the eating activities (e.g. meals, snacks) of people by tracking their wrist motion. Our goal is to automatically de- tect the start and end times of eating activities during free-living. It builds upon previous work done by our research group [6] [7] [8] [21]. The detection is done by segmenting data into segments then classifying the segments as EA (eating activity) and NonEA (non-eating activity) using a Bayesian classier. Previous features used in the classier developed by our group included the sum of acceleration, the amount of manipulation, the amount of wrist roll …

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Deveopment Of Explant Registry And Mechanical Testing Of Pristine And Explained Surgical Mesh, Colin Burns-Heffner Dec 2014

Deveopment Of Explant Registry And Mechanical Testing Of Pristine And Explained Surgical Mesh, Colin Burns-Heffner

All Theses

Abdominal hernia repair is the most commonly performed general surgical procedure, with synthetic surgical mesh commonly used to buttress the defect in the abdominal wall. A majority of surgical mesh is made from Polypropylene (PP), which has been shown to invoke a foreign body response as long as the material remains in the body. Complications such as chronic pain require further investigation of mesh performance in hernia repair to better understand how performance differs for various surgical mesh materials. The broad objective of this thesis is to quantitatively characterize surgical mesh after exposure to human physiology in an in-vivo environment. …

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Combining Modified Atmosphere Packaging And Nisin To Extend The Shelf Life Of Atlantic Salmon (Salmo Salar), Dong Han Dec 2014

Combining Modified Atmosphere Packaging And Nisin To Extend The Shelf Life Of Atlantic Salmon (Salmo Salar), Dong Han

All Theses

Atlantic salmon is often used in laboratory experiments to represent marine fishes. Many researchers try to optimize the levels and dosage of preservatives to maintain the freshness and extend the shelf-life of Atlantic salmon. Little information has been provided about the effectiveness of combined method between MAP and nisin, especially on the preservation of Atlantic salmon. Strong evidences suggest that MAP associated with nisin may have a potential to improve Atlantic salmon storage quality. Preservation effectiveness of combining modified atmosphere package (MAP) and nisin on fresh Atlantic salmon was determined using various methods. Six groups of farmed Atlantic salmon were …

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Numerical Simulation Of The Heat Leakage At The Gasket Region Of Domestic Refrigerators, Feng Gao Dec 2014

Numerical Simulation Of The Heat Leakage At The Gasket Region Of Domestic Refrigerators, Feng Gao

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Computational Fluid Dynamics (CFD) simulations are performed to investigate the heat loss at the gasket of a standard over/under domestic refrigerator. The study numerically simulates a unique experimental test cell with only the gasket region exposed to the ambient environment and other parts protected by insulation (see picture below). The test cell is cubic with an interior cavity having dimensions 2' x 2' x 2' within which a heating element is placed to create a specified temperature difference. A matching set of door and side panels exposes a 2' width of the gasket region to heat transfer with the surroundings. …

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Fast Fission Neutron Detection Using The Cherenkov Effect, Matthew Millard Dec 2014

Fast Fission Neutron Detection Using The Cherenkov Effect, Matthew Millard

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The Cherenkov effect in optically clear media of varying indices of refraction and composition was investigated for quantification of fast neutrons. The ultimate application of the proposed detection system is criticality monitoring. The optically clear medium, composed of select target nuclei, was coupled to a photomultiplier tube. Neutron reaction products of the target nuclei contained within the optical medium emit beta particles and gamma rays that produce Cherenkov photons within the medium which can be detected. Assessed media include quartz (SiO2), sapphire (Al2O3), spinel (MgAl2O4), and zinc sulfide (ZnS), which were irradiated with un-moderated 252Cf. Monte Carlo N-Particle (MCNP) code …

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