Engineering Commons^™

Optimization Of Wsu Total Ankle Replacement Systems, Bradley Jay Elliott

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Total ankle arthroplasty (TAR) is performed in order to reduce the pain and loss of ambulation in patients with various forms of arthritis and trauma. Although replacement devices fail by a number of mechanisms, wear in the polyethylene liner constitutes one of the dominating failure modes. This leads to instability and loosening of the implant. Mechanisms that contribute to wear in the liners are high contact and subsurface stresses that break down the material over time. Therefore, it is important to understand the gait that generates these stresses. Methods to characterize and decrease wear in Ohio TARs have been performed …

Inventory Systems With Transshipments And Quantity Discounts, Gregory Daniel Noble

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This research advances knowledge in the area of inventory systems and the relationship between competing retailers and suppliers of goods. This dissertation studies retailers that face uncertainty in the demand for goods and who purchase the goods from a single supplier. A game theoretic methodology is developed to analyze supplier pricing decisions and retailer quantity decisions and interactions in a competitive transshipment system where quantity discounts are offered. The system studied differs from previous work in the subject by introducing quantity discounts from supplier to retailer into a system of competitive retailers that transship stock. Analysis of these systems focuses …

Human Action Recognition By Principal Component Analysis Of Motion Curves, Daniel Stephen Chivers

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Human action recognition is used to automatically detect and recognize actions per- formed by humans in a video. Applications include visual surveillance, human-computer interaction, and robot intelligence, to name a few. An example of a surveillance application is a system that monitors a large public area, such as an airport, for suspicious activity. In human-machine interaction, computers may be controlled by simple human actions. For example, the motion of an arm may instruct the computer to rotate a 3-D model that is being displayed. Human action recognition is also an important capability of intelligent robots that interact with humans.

General …

Computational Investigation Of Ethanol And Bifuel Feasibility In Solstice Engine, Adam Michael Blake

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A Gasoline Direct Injection (GDI) engine enables an increased fuel efficiency and higher power output than a conventional Port Fuel Injection (PFI) system. By injecting pressurized fuel straight into each cylinder of an internal-combustion engine, the degree of fuel atomization is increased, as well as the fuel vaporization rate. In order to further harness the effects of direct injection, ethanol is implemented as a fuel. The cooling effect of ethanol fuel droplets changing to vapor inside the combustion chamber facilitates a higher compression ratio, thus increasing engine power and efficiency. Three dimensional computational simulation is used to investigate the feasibility …

Traffic Surveillance Using Low Cost Continuous Wave (Cw) Doppler Radars, Wu Yang

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Low cost un-modulated continuous wave (CW) radar (CW Doppler radar) can be used to measure the speed of a vehicle. Traditionally, a radar gun, a lidar gun or a speed camera is used to capture a speeding vehicle. A radar gun can either measure the fastest vehicle or the vehicle with the strongest reflection. If a radar gun is used, a police officer must determine which vehicle has the speed shown on the screen of the radar gun. A lidar gun can precisely detect a speeding vehicle, but it requires precise aiming. When a camera is used, a picture will …

High-K Material Based Leaky-Wave Antenna Design, Implementation, And Manufacture, Jiahui Wang

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Leaky-wave antennas are a class of antennas which apply a traveling wave on a guiding structure as the main radiation mechanism. The properties of leaky-wave antennas are light weight, easy to fabricate, and readily integrated into conventional millimeter-wave systems. These features make leaky-wave antennas attractive. The most important characteristic is that the antenna can steer the beam direction through changing the operating frequency rather than switching the antenna itself. Variety types of leaky-wave antennas have been introduced and developed during the past 70 years. However, there is no existing leaky-wave antenna which can widely steer the beam scanning angle by …

Regulation Of The Transcription And Subcellular Localization Of The Tumor Suppressor Pten By Δnp63Α, Mary Kathryn Leonard

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Non-melanoma skin cancers (NMSCs) are the most common form of cancer in the United States with an estimated 3.5 million new cases each year. Surgical excision is the main treatment for NMSC, but leaves the potential for disfiguring scars and does not fully reduce the risk of recurrence since the surrounding tissue is also sun damaged and may contain tumor-promoting mutations. By understanding the molecular etiology of NMSC we may be able to expand treatment options to more than just resection. Normal epidermal development is dependent upon the expression of the transcription factor p63. Amplification of the ΔNp63α isoform is …

Uhf-Sar And Lidar Complementary Sensor Fusion For Unexploded Buried Munitions Detection, Randy S. Depoy Jr.

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Given the UHF bands properties of foliage and round penetration, a UHF-SAR image contains both above- and below-surface scatterers. The problem of detecting sub-surface objects is problematic due to the presence of above-surface scatterers in the detection images. In case of a single-pass anomaly image or a two-pass change image, the resulting anomalies or changes are due to scatterers above and below the surface, where the above surface anomalies/changes act as confusers. LIDAR digital elevation models (DEM) provide georegistered information about the above-surface objects present in the UHF-SAR scene. Detection of the above-surface objects in the LIDAR domain is used …

Behavioral Signature-Based Framework For Identifying Unsatisfiable Variable Mappings Between Digital Designs, Vaibhav Uday Tendulkar

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Throughout its design process (from specification to implementation) a digital circuit goes through a variety of structural changes. These changes are introduced primarily due to the use of automated tools in the design process. Checking whether the Boolean functions representing the two designs are equivalent is thus necessary to verify if a design implementation adheres to its specification. Combinational Equivalence Checking (CEC) - a process of determining whether two combinational design functions are equiv-alent, has been one of the most researched Boolean matching problems. The well-known CEC techniques that have been proposed adopt some kind of a formal approach such …

Measurement Of Static And Dynamic Performance Characteristics Of Electric Propulsion Systems, Aron Jon Brezina

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Today's unmanned aerial vehicles are being utilized by numerous groups around the world for various missions. Most of the smaller vehicles that have been developed use commercially-off-the-shelf parts, and little information about the performance characteristics of the propulsion systems is available in the archival literature. In light of this, the aim of the present research was to determine the performance of various small-scale propellers in the 4.0 to 6.0 inch diameter range driven by an electric motor. An experimental test stand was designed and constructed in which the propeller/electric motor was mounted in a wind tunnel for both static and …

Nano-Scale Rf/Microwave Characterization Of Materials' Electromagnetic Properties, Joshua Allen Myers

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There are two words that describe the direction of today's electronic technology, smaller and faster. With the ever decreeing size scientists and engineers must have a way to characterize materials in the nm range. In this thesis characterization of nano-materials is discussed based on scanning probe microscopy and an in-depth look at RF/microwave frequencies by scanning microwave microscopy. Recently, low-temperature spin-sprayed ferrite films (Fe3O4) with a high self-biased magnetic anisotropy field have been reported, showing FMR frequency>5 GHz. Such films hold great potential for RF/microwave devices and find immediate applications. In this study, we performed in situ scanning microwave …

Digital Wideband Spectral Sensing Receiver, Lawrence D. Burich

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Detecting, channelizing, and characterizing radio frequency signals is a fundamental requirement for electronic warfare receivers as well as in commercial wireless applications where it is important to determine activity/inactivity in specified bands for spectral sharing and interference avoidance. Spectral sensing receivers are required to cover bandwidths in the GHz range and channelize signals into frequency bins in the kilo-hertz or mega-hertz range depending on the application. The difficulty is to detect, then determine spectral characteristics of multiple signals with varying power levels and signal characteristics in real time. A number of current Digital Wideband Spectral Sensing Receiver (DWSSR) architectures are …

Prediction Of Optimal Bayesian Classification Performance For Ladar Atr, Kristjan H. Greenewald

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We consider the problem of LADAR ATR classifier performance prediction in the presence of arbitrary nuisance parameters including but not limited to pose. We use several noise models for both range images and point clouds that are significantly more accurate and complex than the Gaussian models used by previous non-Monte Carlo prediction methods. Two accurate new methods of efficiently predicting the optimum Bayesian classification performance are then derived, and applied to the noise models. Advantages of these methods include significant gains in accuracy for medium to high noise levels and the ability to handle target near symmetry. Extensions are developed …

'Omic' Evaluation Of The Region Specific Changes Induced By Non-Cholinergic Diisopropylfluorophosphate (Dfp) Exposure In Fischer 344 Rat Brain, Deirdre A. Mahle

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Organophosphorous compounds (OPs) are a class of serine esterase inhibitors that have widespread application as pesticides, veterinary pharmaceuticals and chemical warfare agents. Environmental contamination is ubiquitous. The threat of exposure is a concern for both military and civilian populations. Acute inhibition of acetylcholinesterase by OPs triggers a cholinergic crisis that results in muscle flaccidity, paralysis, convulsions and death. At low doses OPs can alter neuronal differentiation, cell signaling, behavior and cognition through unknown mechanisms. An imbalance of reactive oxygen species may be implicated in the adverse effects of OPs. An integrated approach using both metabolomic and transcriptomic techniques was used …

An Evaluation Of Discharge Policies At A Generic Acute Care Hospital, Elizabeth A. Crawford

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One of the main issues faced within the U.S. healthcare continuum is ineffective care transition. Ineffective transitions from one area of care to the next can lead to a reduction in quality of care, an increased risk of readmission, and an increase in healthcare costs. According to the National Transitions of Care Coalition (NTOCC), as many as 42% of the hospitals surveyed reported that care transitions during coordinated care delivery do not go as planned. One of the primary reasons for ineffective care transition is poor discharge planning. The purpose of this research is to analyze the effect of various …

Characterization, Stability, And Transport Through Defects In Graphene Nanoribbons, Sri Krishna Divya Pemmaraju

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Graphene nanoribbons (GNRs) constitute a new class of nanostructured materials with unique properties and significant potential for applications. During production of GNRs, defects are generally introduced within the lattice. Assessment of defects' stability and characterization of their effects on GNRs are therefore very important for predicting GNRs performance under realistic circumstances. Here we consider various possible defects, namely the ones caused by removal/addition of carbon atoms from/to the lattice as well as those caused by bond rotation/rearrangement. Our study is based on ab initio geometry optimization and electronic structure calculations. We determine which defects can be stable in graphene nanoflakes …

Extension Of Polar Format Scene Size Limits To Squinted Geometries, Matthew Steven Horvath

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The Polar Format Algorithm (PFA) is an often used algorithm to image synthetic aperture radar (SAR) phase history data. The algorithm relies on a far-field approximation wherein the curved wavefront of the transmitted pulses is approximated as a planar wavefront, introducing spatially variant phase errors in the phase history. While allowing for faster image formation compared to more exact imaging algorithms such as convolution backprojection, these phase errors lead to the distortion and defocus of point targets, degrading the quality of the resulting imaged scene.

Historically, a Taylor expansion has been used to approximate the phase errors leading to distortion …

Cloudvista: A Framework For Interactive Visual Cluster Exploration Of Big Data In The Cloud, Zhen Li

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With the development and deployment of ubiquitous information sensing, mobile devices,wireless sensor networks, RFID readers, simulation, and computer generated software logs, big data have become precious resources for scientific study, business intelligence, and national security. As one of the most intuitive and effective analysis methods,visual cluster analysis remains as a significant challenge for big datasets. First, existing visualization models need to be updated to process big data in parallel. Second, processing big data inevitably bring large latency, which conflicts the requirement of interactivity. In this thesis, we develop the CloudVista framework to address the common problems with data reduction methods …

System Optimization And Patient Translational Motion Correction For Reduction Of Artifacts In A Fan-Beam Ct Scanner, Zachary Gordon Lee Wise

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In computed tomography (CT) systems, many different artifacts may be present in the reconstructed image. These artifacts can greatly reduce image quality. For our laboratory prototype CT system, a fan-beam/cone-beam focal high-resolution computed tomography (fHRCT) scanner, the major artifacts that affect image quality are distortions due to errors in the reconstruction algorithm's geometric parameters, ring artifacts caused by uncalibrated detectors, cupping and streaking created by beam hardening, and patient-based motion artifacts. Optimization of the system was required to reduce the effects of the first three artifact types, and an algorithm for correction of translational motion was developed for the last. …

Computational Study On Micro-Pilot Flame Ignition Strategy For A Direct Injection Stratified Charge Rotary Engine, Zachary Steven Votaw

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The Office of Security of Defense's Assured Fuels Initiative has recently been pressing for a single fuel battle space. This endeavor requires modifying many of the vehicle power plants currently in operation throughout the Armed Forces. The RQ-7 Shadow, an unmanned aerial vehicle (UAV) utilized by the Marine Corp and Army for reconnaissance purposes, is powered by UEL's AR741 rotary engine and functions on aviation fuel. One effort underway has been focused on developing this rotary engine system to operate on heavy fuels using direct injection technology and charge stratification. Although the rotary engine has many advantages over standard reciprocating …

Limitations Of Functional Recovery Of Stretch Reflex Circuitry After Peripheral Nerve Regeneration, Gabrielle Marie Horstman

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Peripheral nerve regeneration fails to restore complete normal function after surgical repair of severed nerves, and this failure has primarily been attributed to errors in connecting with peripheral targets. However, recent evidence suggests that central deficits remain even after peripheral target reinnervation is largely successful. It has long been established that regeneration fails to restore the stretch reflex despite observation that many of the neural components are intact. Regenerated Ia afferents are largely successful in reinnervating muscle spindles, are capable of encoding stretch, and elicit EPSPs in homonymous motoneurons, while regenerated motor pools are capable of responding to uninjured sources …

Managing Patient Test Data In Primary Care: Developing And Evaluating A System For Test Tracking To Enhance Processes, Safety, And Understanding Of Performance, Jennifer M. Cloud-Buckner

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Patient testing is vital for primary care and serves as a gateway to specialty healthcare. Patient safety is worsened when testing orders (e.g., laboratory, imaging orders) are not tracked, results are lost, or abnormal results lack patient notification and follow-up. Non-standardized testing management reduces resilience; affects clinical outcomes; and increases errors, costs, workload, and delays.

To address the need for testing management improvements, this research followed four phases in six objectives: (1) In Phase I initial survey, assess perceptions, attitudes, and behaviors of practicing healthcare clinicians and administrators about testing, safety, and technology; (2) In Phase II system design, design …

Adaptive Noise Reduction Techniques For Airborne Acoustic Sensors, Ryan Michael Fuller

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Ground and marine based acoustic arrays are currently employed in a variety of military and civilian applications for the purpose of locating and identifying sources of interest. An airborne acoustic array could perform an identical role, while providing the ability to cover a larger area and pursue a target. In order to implement such a system, steps must be taken to attenuate environmental noise that interferes with the signal of interest. In this thesis, we discuss the noise sources present in an airborne environment, present currently available methods for mitigation of these sources, and propose the use of adaptive noise …

Statistical Methods For Image Change Detection With Uncertainty, Andrew James Lingg

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Sensors capable of collecting wide area motion imagery (WAMI), video synthetic aperture radar (SAR), and other high frame rate sensor modalities provide massive amounts of high-resolution data. Such data allows for the use of multiple images in exploitation tasks which may have traditionally used single images or single pairs of images. One such task is change detection. This dissertation presents new statistical methods for change detection that provide for the exploitation of multiple images per pass. Uncertainty in image registration can degrade change detection performance. Registration accuracy is analyzed, and the impact of registration uncertainty is propagated to the registered …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Characterization Of Doped Gallium Nitride Substrates, Jack Lee Owsley Iii

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In this thesis the characteristics of five bulk semi-insulated doped gallium nitride samples provided by Kyma Technologies, Inc were explored. The five GaN samples were grown on sapphire substrates by hydride vapor phase epitaxy (HVPE) and doped with different concentrations of iron, hydrogen, carbon, oxygen and silicon. The first step of characterization was measuring the optical absorption of all the samples using a UV-NIR fiber spectrometer. Through this procedure it was found that they all showed a strong absorption at 518 nm. Thus, time-resolved differential transmission measurements were conducted at this wavelength using the second harmonic generation (SHG) of a …

An Optimization Approach To Indoor Location Problem Based On Received Signal Strength, Lei Zheng

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This research was motivated by the desire of a Fortune 100 retail company to track its customers' behaviors through the implementation of a low-cost indoor location system using received signal devices. Indoor location through received signal strength (RSS) is of low costs, yet it suffers from poor accuracy due to lack of direct line-of-sight, multi-path ratio propagation, and various interferences. To improve its location estimation accuracy, therefore, we propose a mathematical programming based propagation approach for RSS based location systems. The core of our approach is an optimization model that minimizes the sum of squared errors of signal strength. In …

Compact Leaky Wave Antenna Using Ferroelectric Materials, Hyung Min Jeon

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Leaky wave antenna continuously attracts a lot interests for tuning the radiation direction over a large angle. Various types of leaky wave antenna have been developed since 1940. However, most of these leaky wave antennas suffered from their excessive volume and the required wide range of operating frequency (bandwidth) to achieve a large tuning angle. To circumvent these challenges, research in this thesis is focused on implementation of material (like PZT) with high dielectric constant (k) in a rectangular waveguide leaky wave antenna. Due to the high dielectric constant of PZT ~ 1,900, the propagation wavelength in the waveguide can …

Optimization Of Spectrum Allocation In Cognitive Radio And Dynamic Spectrum Access Networks, Tao Zhang

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Spectrum has become a treasured commodity. However, many licensed frequency bands exclusively assigned to the primary license holders (also called primary users) remain relatively unused or under-utilized for most of the time. Allowing other users (also called secondary users) without a license to operate in these bands with no interference becomes a promising way to satisfy the fast growing needs for frequency spectrum resources. A cognitive radio adapts to the environment it operates in by sensing the spectrum and quickly decides on appropriate frequency bands and transmission parameters to use in order to achieve certain performance goals. One of the …

Abstraction Driven Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu

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Cloud computing has changed the way organizations create, manage, and evolve their applications. While many organizations are eager to use the cloud, tempted by substantial cost savings and convenience, the implications of using clouds are still not well understood. One of the major concerns in cloud adoption is the vendor lock-in of applications, caused by the heterogeneity of the numerous cloud service offerings. Vendor locked applications are difficult, if not impossible to port from one cloud system to another, forcing cloud service consumers to use undesired or suboptimal solutions. This dissertation investigates a complete and comprehensive solution to address the …