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Full-Text Articles in Engineering

Adaptive Routing Algorithm For Priority Flows In A Network, Timothy J. Carbino Jun 2012

Adaptive Routing Algorithm For Priority Flows In A Network, Timothy J. Carbino

Theses and Dissertations

This research presents the development of an Adaptive Routing Algorithm for Priority (ARAP) flows in a Network. Devices in today's battle space require information to function. Additional bandwidth requirements for such devices place an increased burden on the already congested networks in the battle space. Some devices require real time information (high priority) and other devices will not require real time information (low priority). Existing protocols treat the network like an opaque entity and have little knowledge of user requirements. User requirement information is available in tactical networks and we can take advantage of the known requirements to better optimize …

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A Real-Time Strategy Agent Framework And Strategy Classifier For Computer Generated Forces, Lyall J. Di Trapani Jun 2012

A Real-Time Strategy Agent Framework And Strategy Classifier For Computer Generated Forces, Lyall J. Di Trapani

Theses and Dissertations

This research effort is concerned with the advancement of computer generated forces AI for Department of Defense (DoD) military training and education. The vision of this work is agents capable of perceiving and intelligently responding to opponent strategies in real-time. Our research goal is to lay the foundations for such an agent. Six research objectives are defined: 1) Formulate a strategy definition schema effective in defining a range of RTS strategies. 2) Create eight strategy definitions via the schema. 3) Design a real-time agent framework that plays the game according to the given strategy definition. 4) Generate an RTS data …

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Intra-Procedural Path-Insensitive Grams (I-Grams) And Disassembly Based Features For Packer Tool Classification And Detection, Scott E. Gerics Jun 2012

Intra-Procedural Path-Insensitive Grams (I-Grams) And Disassembly Based Features For Packer Tool Classification And Detection, Scott E. Gerics

Theses and Dissertations

The DoD relies on over seven million computing devices worldwide to accomplish a wide range of goals and missions. Malicious software, or malware, jeopardizes these goals and missions. However, determining whether an arbitrary software executable is malicious can be difficult. Obfuscation tools, called packers, are often used to hide the malicious intent of malware from anti-virus programs. Therefore detecting whether or not an arbitrary executable file is packed is a critical step in software security. This research uses machine learning methods to build a system, the Polymorphic and Non-Polymorphic Packer Detection (PNPD) system, that detects whether an executable is packed …

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Design, Fabrication And Testing Of Tunable Rf Meta-Atoms, Derrick Langley Jun 2012

Design, Fabrication And Testing Of Tunable Rf Meta-Atoms, Derrick Langley

Theses and Dissertations

Metamaterials are engineered structures designed to alter the propagation of electromagnetic waves incident upon the structure. The focus of this research was the effect of metamaterials on electromagnetic signals at radio frequencies. RF meta-atoms were investigated to further develop the theory, modeling, design and fabrication of metamaterials. Comparing the analytic modeling and experimental testing, the results provide a deeper understanding into metamaterials which could lead to applications for beam steering, invisibility cloaking, negative refraction, super lenses, and hyper lenses. RF meta-atoms integrated with microelectromechanical systems produce tunable meta-atoms in the 10 - 15 GHz and 1 - 4 GHz frequency …

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Detecting Hardware-Assisted Hypervisor Rootkits Within Nested Virtualized Environments, Daniel B. Morabito Jun 2012

Detecting Hardware-Assisted Hypervisor Rootkits Within Nested Virtualized Environments, Daniel B. Morabito

Theses and Dissertations

Virtual machine introspection (VMI) is intended to provide a secure and trusted platform from which forensic information can be gathered about the true behavior of malware within a guest. However, it is possible for malware to escape a guest into the host and for hypervisor rootkits, such as BluePill, to stealthily transition a native OS into a virtualized environment. This research examines the effectiveness of selected detection mechanisms against hardware-assisted virtualization rootkits (HAV-R) within a nested virtualized environment. It presents the design, implementation, analysis, and evaluation of a hypervisor rootkit detection system which exploits both processor and translation lookaside buffer-based …

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Cross Hallway Detection And Indoor Localization Using Flash Laser Detection And Ranging, Istvan M. Prileszky Jun 2012

Cross Hallway Detection And Indoor Localization Using Flash Laser Detection And Ranging, Istvan M. Prileszky

Theses and Dissertations

A flash LADAR is investigated as a source of navigation information to support cross-hallway detection and relative localization. To accomplish this, a dynamic, flexible simulation was developed that simulated the LADAR and the noise of a LADAR system. Using simulated LADAR data, algorithms were developed that were shown to be effective at detecting cross hallways in simulated ideal environments and in simulated environments with noise. Relative position was determined in the same situations. A SwissRanger SR4000 flash LADAR was then used to collect real data and to verify algorithm performance in real environments. Hallway detection was shown to be possible …

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Multi-Observation Continuous Density Hidden Markov Models For Anomaly Detection In Full Motion Video, Matthew P. Ross Jun 2012

Multi-Observation Continuous Density Hidden Markov Models For Anomaly Detection In Full Motion Video, Matthew P. Ross

Theses and Dissertations

An increase in sensors on the battlefield produces an abundance of collected data that overwhelms the processing capability of the DoD. Automated Visual Surveillance (AVS) seeks to use machines to better exploit increased sensor data, such as by highlighting anomalies. In this thesis, we apply AVS to overhead Full Motion Video (FMV). We seek to automate the classification of soldiers in a simulated combat scenario into their agent types. To this end, we use Multi-Dimensional Continuous Density Hidden Markov Models (MOCDHMMs), a form of HMM which models a training dataset more precisely than simple HMMs. MOCDHMMs are theoretically developed but …

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Simulation Modeling And Analysis Of The Impact Of Individual Mobility Augmentee Loss At The Tanker Airlift Control Center, Megan A. Leiter Jun 2012

Simulation Modeling And Analysis Of The Impact Of Individual Mobility Augmentee Loss At The Tanker Airlift Control Center, Megan A. Leiter

Theses and Dissertations

The Tanker Airlift Control Center (TACC) operates as the execution arm for Air Mobility Command's Global Reach mission. The Command and Control Directorate (XOC) monitors the execution of missions tasked to the 18th Air Force. Approximately 70% of the personnel on the operations floor are considered Individual Mobility Augmentees (IMA). Adjustments in manpower, specifically the loss of IMAs, at the TACC/XOCG may impact their responsiveness to mission deviations. This research develops a discrete event simulation using a combination of SME and historical data to capture the activities of a section of the personnel on the operations floor and the potential …

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An Application Of Con-Resistant Trust To Improve The Reliability Of Special Protection Systems Within The Smart Grid, Crystal M. Shipman Jun 2012

An Application Of Con-Resistant Trust To Improve The Reliability Of Special Protection Systems Within The Smart Grid, Crystal M. Shipman

Theses and Dissertations

This thesis explores an application of a con-resistant trust mechanism to improve the performance of communications-based special protection systems to further enhance their effectiveness and resiliency. New initiatives in the energy sector are paving the way for the emergent communications-based smart grid technology. Smart grids incorporate modern technologies in an effort to be more reliable and efficient. However, with the benefits of this new technology comes added risk. This research utilizes a con-resistant trust mechanism as a method to quickly identify malicious or malfunctioning protection system nodes in order to mitigate the resulting instabilities in the smart grid. The feasibility …

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Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock Jun 2012

Implementation Of Branch-Point-Tolerant Wavefront Reconstructor For Strong Turbulence Compensation, Michael J. Steinbock

Theses and Dissertations

Branch points arise in optical transmissions due to strong atmospheric turbulence, long propagation paths, or a combination of both. Unfortunately, these conditions are very often present in desired operational scenarios for laser weapon systems, optical communication, and covert imaging, which suffer greatly when traditional adaptive optics systems either cannot sense branch points or implement non-optimal methods for sensing and correcting branch points. Previous research by Pellizzari presented a thorough analysis of various novel branch point tolerant reconstructors in the absence of noise. In this research a realistic model of the Air Force Institute of Technology's adaptive optics system is developed …

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Multi-User Methods For Fea Pre-Processing, Prasad Weerakoon Jun 2012

Multi-User Methods For Fea Pre-Processing, Prasad Weerakoon

Theses and Dissertations

Collaboration in engineering product development leads to shorter product development times and better products. In product development, considerable time is spent preparing the CAD model or assembly for Finite Element Analysis (FEA). In general Computer-Aided Applications (CAx) such as FEA deter collaboration because they allow only a single user to check out and make changes to the model at a given time. Though most of these software applications come with some collaborative tools, they are limited to simple tasks such as screen sharing and instant messaging. This thesis discusses methods to convert a current commercial FEA pre-processing program into a …

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Chemical Potential Perturbation: A Method To Predict Chemical Potential Using Molecular Simulations, Stan G. Moore Jun 2012

Chemical Potential Perturbation: A Method To Predict Chemical Potential Using Molecular Simulations, Stan G. Moore

Theses and Dissertations

A new method, called chemical potential perturbation (CPP), has been developed to predict the chemical potential as a function of composition in molecular simulations. The CPP method applies a spatially varying external potential to the simulation, causing the composition to depend upon position in the simulation cell. Following equilibration, the homogeneous chemical potential as a function of composition can be determined relative to some reference state after correcting for the effects of the inhomogeneity of the system. The CPP method allows one to predict chemical potential for a wide range of composition points using a single simulation and works for …

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Evaluation Of Advanced Conductive Nickel Materials For Strain Sensing In Carbon Fiber Reinforced Polymers, Michael Christian Koecher Jun 2012

Evaluation Of Advanced Conductive Nickel Materials For Strain Sensing In Carbon Fiber Reinforced Polymers, Michael Christian Koecher

Theses and Dissertations

Due to their unique properties, carbon fiber reinforced polymers (CFRP) are becoming ever more prevalent in today's society. Unfortunately, CFRP suffer from a wide range of failure modes and structural health monitoring methods are currently insufficient to predict these failures. It is apparent that self-sensing structural health monitoring could be advantageous to protect consumers from catastrophic failure in CFRP structures. Previous research has shown that embedded nickel nanostrand nanocomposites can be used to instantaneously measure strain in carbon fiber composites, but these methods have been severely limited and can induce high stress concentrations that compromise the structural integrity of the …

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Microscopic Light Field Particle Image Velocimetry, Bryce Adam Mcewen Jun 2012

Microscopic Light Field Particle Image Velocimetry, Bryce Adam Mcewen

Theses and Dissertations

This work presents the development and analysis of a system that combines the concepts of light field microscopy and particle image velocimetry (PIV) to measure three-dimensional velocities within a microvolume. Rectanglar microchannels were fabricated with dimensions on the order of 350-950 micrometers using a photolithographic process and polydimethylsiloxane (PDMS). The flow was seeded with fluorescent particles and pumped through microchannels at Reynolds numbers ranging from 0.016 to 0.028. Flow at Reynolds numbers in the range of 0.02 to 0.03 was seeded with fluorescent particles and pumped through microchannels. A light field microscope with a lateral resolution of 6.25 micrometers and …

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Structural Properties Of Iclt Wall Panels Composed Of Beetle Killed Wood, David Edward Wilson Jun 2012

Structural Properties Of Iclt Wall Panels Composed Of Beetle Killed Wood, David Edward Wilson

Theses and Dissertations

Interlocking Cross Laminated Timber (ICLT) wall panels are a new wood construction product similar to Cross Laminated Timber panels. Besides being an innovative structural system, they also utilize beetle killed timber from many of the forests that have been devastated by the Mountain Pine Beetle. Three tests were performed on three ply ICLT panels measuring 8 feet (2.44m) wide, 8 feet (2.44m) tall and 8.5 inches (21.6cm) thick to determine the racking, flexural and axial strengths of the wall panels. After each test was performed the walls were disassembled and investigated for cause of failure. Using the data from the …

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High Reclaimed Asphalt Pavement In Hot Mix Asphalt, Alan Norton Jr Jun 2012

High Reclaimed Asphalt Pavement In Hot Mix Asphalt, Alan Norton Jr

Theses and Dissertations

When old roads have to be replaced, the existing pavement, known as Reclaimed Asphalt Pavement (RAP) is ripped up, milled, and stockpiled and can be used in the creation of new mixes in order to save money and resources. New Jersey state specifications limit the percentage of RAP that can be used to 15% for surface courses and 25% for the intermediate and base courses; however, other states have implemented much higher RAP percentages. The limitations are placed because the interaction between the virgin and residual RAP binder is unknown, with respect to the amount of residual binder that is …

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The Composition And Morphology Of Coal Ash Deposits Collected In An Oxy-Fuel, Pulverized Coal Reactor, Curtis K. Stimpson May 2012

The Composition And Morphology Of Coal Ash Deposits Collected In An Oxy-Fuel, Pulverized Coal Reactor, Curtis K. Stimpson

Theses and Dissertations

Coal ash deposits were collected in a 160 kWth, down-fired oxy-coal reactor under staged and unstaged conditions for four different coals (PRB, Gatling, Illinois #6, and Mahoning). Concentration measurements of carbon, oxygen, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, potassium, calcium, titanium, chromium, manganese, iron, nickel, strontium, and barium were gathered from each deposit sample using scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). Backscattered electron micrographs for each deposit sample were analyzed to gather morphological data. Particle size and shape were studied for each deposit collected. The average particle sizes of the particles in upstream deposits were much larger …

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Mechanical Properties And Mems Applications Of Carbon-Infiltrated Carbon Nanotube Forests, Walter C. Fazio May 2012

Mechanical Properties And Mems Applications Of Carbon-Infiltrated Carbon Nanotube Forests, Walter C. Fazio

Theses and Dissertations

This work explores the use of carbon-infiltrated carbon nanotube (CI-CNT) forests as a material for fabricating compliant MEMS devices. The impacts of iron catalyst layer thickness and carbon infiltration time are examined. An iron layer of 7nm or 10nm with an infiltration time of 30 minutes produces CI-CNT best suited for compliant applications. Average maximum strains of 2% and 2.48% were observed for these parameters. The corresponding elastic moduli were 5.4 GPa and 4.1 GPa, respectively. A direct comparison of similar geometry suggested CI-CNT is 80% more flexible than single-crystal silicon. A torsional testing procedure provided an initial shear modulus …

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Automatic Discovery And Exposition Of Parallelism In Serial Applications For Compiler-Inserted Runtime Adaptation, David A. Greenland May 2012

Automatic Discovery And Exposition Of Parallelism In Serial Applications For Compiler-Inserted Runtime Adaptation, David A. Greenland

Theses and Dissertations

Compiler-Inserted Runtime Adaptation (CIRA) is a compilation and runtime adaptation strategy which has great potential for increasing performance in multicore systems. In this strategy, the compiler inserts directives into the application which will adapt the application at runtime. Its ability to overcome the obstacles of architectural and environmental diversity coupled with its flexibility to work with many programming languages and styles of applications make it a very powerful tool. However, it is not complete. In fact, there are many pieces still needed to accomplish these lofty goals. This work describes the automatic discovery of parallelism inherent in an application and …

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Uv Visible Spectra Analysis Of High Temperature Water Gas Shift Catalysts Made From Iron, Lanthanum, Copper, And Chromium Oxides, Jared C. Brown May 2012

Uv Visible Spectra Analysis Of High Temperature Water Gas Shift Catalysts Made From Iron, Lanthanum, Copper, And Chromium Oxides, Jared C. Brown

Theses and Dissertations

Hydrogen is a vital component in several different chemical reactions as well as a potential fuel source for the future. The water gas shift (WGS) reaction converts CO and water to hydrogen and CO2. The objective of this work is to first, characterize the potential benefits of the addition of lanthanum oxide (lanthana) to the iron-chromium-copper (Fe-Cr-Cu) oxide catalysts industrially used in high temperature water gas shift processes, and second, analyze these catalysts using in-situ UV-Visible spectroscopy. The benefits of each component in the catalyst are discussed as well as potential benefits from the addition of lanthana. Lanthana is a …

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No, Burnout, Flame Temperature, Emissivity, And Radiation Intensity From Oxycombustion Flames, Darrel Patrick Zeltner May 2012

No, Burnout, Flame Temperature, Emissivity, And Radiation Intensity From Oxycombustion Flames, Darrel Patrick Zeltner

Theses and Dissertations

This work produced the retrofit of an air-fired, 150 kW reactor for oxy-combustion which was then used in three oxy-combustion studies: strategic oxy-combustion design, oxy-combustion of petroleum coke, and air versus oxy-combustion radiative heat flux measurements. The oxy-combustion retrofit was accomplished using a system of mass flow controllers and automated pressure switches which allowed safe and convenient operation. The system was used successfully in the three studies reported here and was also used in an unrelated study. A study was completed where a novel high oxygen participation burner was investigated for performance while burning coal related to flame stability, NO, …

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Development Of A Multiple Contact Haptic Display With Texture-Enhanced Graphics, David Burch May 2012

Development Of A Multiple Contact Haptic Display With Texture-Enhanced Graphics, David Burch

Theses and Dissertations

This dissertation presents work towards the development of a multiple finger, worn, dynamic display device, which utilizes a method of texture encoded information to haptically render graphical images for individuals who are blind or visually impaired. The device interacts directly with the computer screen, using the colors and patterns displayed by the image as a means to encode complex patterns of vibrotactile output, generating the texture feedback to render the image. In turn, the texture feedback was methodically designed to enable parallel processing of certain coarse information, speeding up the exploration of the diagram and improving user performance. The design …

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Optimization Of Feature Selection In A Brain-Computer Interface Switch Based On Event-Related Desynchronization And Synchronization Detected By Eeg, Mason Montgomery May 2012

Optimization Of Feature Selection In A Brain-Computer Interface Switch Based On Event-Related Desynchronization And Synchronization Detected By Eeg, Mason Montgomery

Theses and Dissertations

There are hundreds of thousands of people who could benefit from a Brain-Computer Interface. However, not all are willing to undergo surgery, so an EEG is the prime candidate for use as a BCI. The features of Event-Related Desynchronization and Synchronization could be used for a switch and have been in the past. A new method of feature selection was proposed to optimize classification of active motor movement vs a non-active idle state. The previous method had pre-selected which frequency and electrode to use as electrode C3 at the 20Hz bin. The new method used SPSS statistical software to determine …

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A Method For Exploring Optimization Formulation Space In Conceptual Design, Shane Keawe Curtis May 2012

A Method For Exploring Optimization Formulation Space In Conceptual Design, Shane Keawe Curtis

Theses and Dissertations

Formulation space exploration is a new strategy for multiobjective optimization that facilitates both divergent searching and convergent optimization during the early stages of design. The formulation space is the union of all variable and design objective spaces identified by the designer as being valid and pragmatic problem formulations. By extending a computational search into the formulation space, the solution to an optimization problem is no longer predefined by any single problem formulation, as it is with traditional optimization methods. Instead, a designer is free to change, modify, and update design objectives, variables, and constraints and explore design alternatives without requiring …

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Finite Element Analysis Of Transverse Medial Malleolar Fracture Fixation, Ruchi Chande May 2012

Finite Element Analysis Of Transverse Medial Malleolar Fracture Fixation, Ruchi Chande

Theses and Dissertations

Injury to the medial malleolus, the distal end of the tibia and one of the bones comprising the ankle joint, can occur in various loading scenarios. Open reduction/internal fixation (ORIF) to reattach the malleolar fragment to the proximal tibia can be achieved via various devices, however small fragments are particularly challenging to treat. In this study, computational finite element analysis (FEA) was utilized to investigate the fixation of transverse medial malleolar fractures by two cancellous screws or by a new fixation device, the Medial Malleolar Sled™. Cadaveric testing assessed the performance of the two constructs in both tension and torsion. …

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Development, Optimization, And Twisted Adjustment Of An Axial Flow Blood Pump For Fontan Patients, Michael Sciolino May 2012

Development, Optimization, And Twisted Adjustment Of An Axial Flow Blood Pump For Fontan Patients, Michael Sciolino

Theses and Dissertations

Mechanical circulatory support options for patients with a failing Fontan physiology are significantly limited. This research advances the design of a cavopulmonary assist device as a bridge-to-transplant or bridge-to-recovery for Fontans. A fixed-bladed impeller and diffuser for this pump was designed and optimized using ANSYS CFX™ 12.1 software. Building upon the fixed bladed geometry, a novel flexible impeller prototype was created and evaluated by hydraulic testing. In contrast to the fixed design, the flexible impeller enabled a range of blade angles from 60°-150°. Improvement in pump performance was achieved. Pressure generation was found to decrease as a function of higher …

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Brain Controlled Switch, Dimple Bhuta May 2012

Brain Controlled Switch, Dimple Bhuta

Theses and Dissertations

This study aims at designing and implementing a single channel stand-alone Brain-Controlled Switch (BCS) device, which records the electroencephalography (EEG) signals from the scalp using electrodes, amplifies it, eliminates interferences (associated with the EEG signals) and processes the EEG signals to extract and decode temporal signal features to determine user’s intention of regulating an external switch. The design of our “brain-controlled switch” device is implemented using a bio-potential amplifier and a microcontroller. The bio-potential amplifier amplifies the EEG signals to a level sufficient for processing, eliminates interferences and ensures patient safety. The microcontroller (dsPIC30F4013) digitizes the amplified and conditioned analog …

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Characterization Of Superhydrophobic Surfaces Fabricated Using Ac-Electrospinning And Random Particle Deposition, Mohamed Samaha Jr. May 2012

Characterization Of Superhydrophobic Surfaces Fabricated Using Ac-Electrospinning And Random Particle Deposition, Mohamed Samaha Jr.

Theses and Dissertations

Surfaces with static contact angle greater than 150 degrees are typically classified as superhydrophobic. Such coatings have been inspired by the lotus leaf. As water flows over a superhydrophobic surface, "slip effect" is produced resulting in a reduction in the skin-friction drag exerted on the surface. Slip flow is caused by the entrapment of a layer of air between water and the surface. Superhydrophobicity could be utilized to design surfaces for applications such as energy conservation, noise reduction, laminar-to-turbulent-transition delay, and mixing enhancement. A popular method of manufacturing a superhydrophobic surface is microfabrication in which well-designed microgrooves and/or poles are …

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Design, Fabrication, And Testing Of A Pdms Micropump With Moving Membranes, Charles Cartin May 2012

Design, Fabrication, And Testing Of A Pdms Micropump With Moving Membranes, Charles Cartin

Theses and Dissertations

This paper will discuss the design, fabrication, and testing of a Poly(dimethylsiloxane) (PDMS) microfluidic pump. PDMS is commonly described as a soft polymer with very appealing chemical and physical properties such as optical transparency, low permeability to water, elasticity, low electrical conductivity, and flexible surface chemistry. PDMS microfluidic device fabrication is done easily with the use of soft lithography and rapid prototyping. PDMS microfluidic devices make it easier to integrate components and interface devices with particular users, than using typically harder materials such as glass and silicon. Fabrication and design of single and multilayer PDMS microfluidic devices is much easier …

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Quantification Of Preterm Infant Feeding Coordination: An Algorithmic Approach, Pallavi Ramnarain May 2012

Quantification Of Preterm Infant Feeding Coordination: An Algorithmic Approach, Pallavi Ramnarain

Theses and Dissertations

Oral feeding competency is a primary requirement for preterm infant hospital release. Currently there is no widely accepted method to objectively measure oral feeding. Feeding consists primarily of the integration of three individual feeding events: sucking, breathing, and swallowing, and the objective of feeding coordination is to minimize aspiration. The purpose of this work was to quantify the infant feeding process from signals obtained during bottle feeding and ultimately develop a measure of feeding coordination. Sucking was measured using a pressure transducer embedded within a modified silicone bottle block. Breathing was measured using a thermistor embedded within nasal cannula, and …

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