Engineering Commons^™

Performance Prediction Of Quantization Based Automatic Target Recognition Algorithms, Matthew Steven Horvath

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The difficulty of designing automatic target recognition (ATR) systems is that there are many sources of potential variation in the data, often referred to as operating conditions (OCs). Typical evaluation methodologies rely on empirical simulations on fixed datasets, where it can be difficult to fully sample the variations the algorithm will see in application. Here we focus on analytic performance prediction approaches to quantization based algorithms where the sources of variation are assumed conditionally independent. We have focused on three algorithms in particular: multinomial pattern matching (MPM), quantized grayscale matching (QGM), and a quantized mean-squared error approach (QMSE). The first …

Design Of A Novel Low - Cost, Portable, 3d Ultrasound System With Extended Imaging Capabilities For Point-Of-Care Applications, Michail Tsakalakis

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Ultrasound Imaging (USI) or Medical Sonography (MS), as it is formally called, has been widely used in biomedical applications over the last decades. USI can provide clinicians with a thorough view of the internal parts of the human body, making use of sound waves of higher frequencies than humans can perceive. USI systems are considered highly portable and of low-cost, compared to other imaging modalities. However, despite those advantages, Ultrasound Systems (US) and especially 3D ones, have not been yet extensively utilized for Point-of-Care (POC) applications, due to numerous restrictions and artifacts that they currently present.

Hardware complexity and real-time …

A Reconfigurable Spice-Based Cmos Lna Design In 90 Nm Technology Using Ads Rfic Dynamic Link, Pushpak Vasanth Rayudu Arja

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In this thesis, a reconfigurable dual band CMOS LNA with a switching-type circuit topology is proposed. The reconfigurable dual-band LNA can be tuned to operating fre- quency of either 1.575 GHz for global positioning system (GPS) or 2.4GHz for WLAN 802.11b standards. The simulated results performed power gain of 11.2 dB and 12.4 dB, noise figure of 3.4 dB and 2.9 dB, input return loss(S11) of -25.26 dB and-21.4 dB, third- order input intercept point of -3.12 dBm and -2.137 dBm and the design dissipates 8.9 mW and 4.68 mW of power at 1.2 V power supply at the two …

Vitamin D Receptor And 1Α, 25-Dihydroxyvitamin D3 Mediated Regulation Of Δnp63Α, Hill Tremayne Natasha

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1alpha, 25-dihydroxyvitamin D3 (VD3), the ligand for the Vitamin D Receptor (VDR), functions to both inhibit cell growth and promote cell survival. High-dose VD3 is being utilized as a cancer preventive therapy for melanoma, breast and colorectal cancers, without a complete understanding of VD3/VDR signaling. DeltaNp63alpha, considered to be a proto-oncogene, is overexpressed in non-melanoma skin cancers (NMSCs), induces VDR gene expression and promotes keratinocyte proliferation, and may serve to exacerbate non-melanoma skin cancer. The objective of this dissertation was to determine whether VDR/VD3 signaling promotes keratinocyte proliferation by up-regulating DeltaNp63alpha. I showed that VDR increases DeltaNp63alpha expression at both …

A Computational Study Of A Photovoltaic Compound Parabolic Concentrator, William M. Vance

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Routines have been written and added to the Wright State developed solar system simulation program called Solar_PVHFC to model incident solar radiation for a compound parabolic concentrator (CPC) that uses solar panels (photovoltaic panels) to produce electrical energy. Solar_PVHFC is a program that models a solar energy system composed of solar panels to produce electricity from the sun, hydrogen storage tanks to chemically store the energy produced by the solar panels, and fuel cells to convert between electrical and chemical energy when required. Solar_PVHFC features several adjustable parameters to model a solar panel, hydrogen storage, and fuel cell system. Now …

Measuring Pulse Rate Variability During Motion Artifact With A Non-Contact, Multi-Imager Photoplethysmography System, Zachary Adam Kiehl

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Non-contact imaging photoplethysmography is an exciting new field based on the principles of traditional photoplethysmography where viable signals can now be acquired without the use of contact equipment. Recent advances regarding non-contact imaging photoplethysmography have permitted a wide range of new possibilities focused on sensing the cardiopulmonary system. Physiological metrics such as pulse rate, respiration rate, and pulse rate variability can be obtained by current photoplethysmographic imaging methods. Although previous systems were challenged by head-motion artifacts, the mitigation of rigid head-motion artifacts has been demonstrated with a multi-imager design. This study investigated the feasibility and accuracy of pulse rate variability …

Neural Correlates Of Convergence Eye Movements In Convergence Insufficiency Patients Vs Normal Binocular Vision Controls: An Fmri Study, Chirag Bharatkumar Limbachia

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Convergence Insufficiency is a binocular vision disorder, characterized by reduced ability of performing convergence eye movements. Absence of convergence causes, eye strain, blurred vision, doubled vision, headaches, and difficulty reading due frequent loss of place. These symptoms commonly occur during near work. The purpose of this study was to quantify neural correlates associated with convergence eye movements in convergence insufficient (CI) patients vs. normal binocular vision (NBV) controls, and to examine statistical differences between them. Functional magnetic resonance imaging (fMRI) scans were collected using a 3T Siemens scanner. A disparity-driven convergence task was designed using a standard block design approach, …

A Workload Balanced Mapreduce Framework On Gpu Platforms, Yue Zhang

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The MapReduce framework is a programming model proposed by Google to process large datasets. It is an efficient framework that can be used in many areas, such as social network, scientific research, electronic business, etc. Hence, more and more MapReduce frameworks are implemented on different platforms, including Phoenix (based on multicore CPU), MapCG (based on GPU), and StreamMR (based on GPU). However, these MapReduce frameworks have limitations, and they cannot handle the collision problem in the map phase, and the unbalanced workload problems in the reduce phase. To improve the performance of the MapReduce framework on GPGPUs, in this thesis, …

Split Ring Resonator Design For Agricultural Based Applications, Joshua David Compaleo

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Recent advances with manufactured electromagnetic materials known as metamaterials are paving the way to use microwave technology in agricultural development and harvesting. It has been proposed that split ring resonators could be placed on the surface of fruit or vegetables such that the resonant behavior may be monitored and used to estimate the ripeness level. The method is non-destructive and could enable monitoring of large quantities of produce or even be tailored to hand-held devices for consumers. However, the understanding of corresponding changes in the proposed device's resonant behaviors and ripeness levels are limited. In addition, fruit and vegetables are …

Strain-Induced Energy Band-Gap Opening Of Silicene, Zhonghang Ji

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Inspired by the success of graphene, various two dimensional (2D) structures on different substrates have been proposed. Among others, an allotropic form of silicon, coined "silicene" was shown to exhibit similar properties with graphene of a zero band gap and a Dirac cone shape at the K point in the Brillouin zone. Similar to its counterpart graphene, one of the main obstacles to applying silicene in modern electronics is the lack of an energy band gap. In this work, a systematic study was presented on the structural and electronic properties of single and bi-layered silicon films under various in-plane biaxial …

Hardware Trojan Detection In Cryptography Ip Cores By Library Encoding Method, Dinesh Varma Penumetcha

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Security is the primary issue in current internet world through both software and hardware. The ever increase in demand of consumer electronics requires less design cycle. To speedup design cycle, companies are approaching third parties for common applications IPs like USB, cryptography, DSP etc. These third parties can introduce a malicious content, which is called Trojan. Trojan in the netlist can activate only with special input/trigger. Available Trojan detection techniques like delay, area, power fingerprinting techniques and Automatic Test Pattern Generator (ATPG) method are not suitable as they take more time, less accurate. This thesis presents a hardware Trojan detection …

High-Efficiency Wideband Class-F Power Amplifier With Electronically Tunable Resonant Network, Alex D. Compton

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This thesis presents a high-efficiency Class-F power amplifier (PA) operating from 30-88 MHz through the use of an electronically tunable resonant network. While conventional Class-F designs are limited to operation over less than an octave, the proposed design utilizes reconfigurable reactive elements in order to cover the entire VHF-FM frequency range. A real circuit implementation using GaN HEMT is designed and simulated, with the notable design considerations examined in detail. A minimum power added efficiency (PAE) of 71.7% is achieved across the band, at output powers = 49.2 dBm. This combination of high output power and high-efficiency operation across a …

Left Ventricle Volume Reconstruction To Minimize Scanning Time: Slice-Fitting Method, Prateek Kalra

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Assessment of left ventricle volume is usually done for diagnosis and prognosis of heart diseases. Slice-summation method is a standard method used to compute left ventricle volume where region of interest from several short axis (SA) slices are added. There are some limitations to this method, however. It requires short-axis slices to be taken parallel to the mitral valve plane from the base to apex. Moreover, scanning several short-axis slices is a tedious and time consuming process especially for studies that require several hundreds datasets. There are some existing methods to reconstruct left ventricle volume but most of them depend …

Virtual Agent Interaction - Improving Cognitive Abilities And Trust For A Complex Visual Search Task, Heather H. Milecki

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Introduction: This thesis research examined a novel decision support aid ("Spatial Cue + Virtual Agent") on human performance in a simulated complex visual search task. Method: Participants in the "Control" condition did not receive support from an aid. Participants in the "Spatial Cue" condition received support from an aid in the form of a bounding box. Participants in the "Spatial Cue + Virtual Agent" condition received support from an aid in the form of a bounding box and a virtual agent. The aids' reliability was held constant at one level, 70 percent. Image difficulty was based on clutter; clutter was …

Theoretical Throughput Capacity: Capabilities Of Human Information Processing During Multitasking, Aerial N. Camden

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Technological advancements in automation have allowed humans to collect data at exorbitant rates. As a result, human multitasking as become an integral part of many government, industrial, and routine activities. However, multitasking can be difficult to study, primarily due to the lack of objective metrics. The Human Operator Informatic Model (HOIM) is an information-theory based model that has been recently developed to combat these difficulties. The HOIM is based on Shannon information theory and can provide an objective, meaningful measure to describe system complexity and overall multitasking performance. The main goal of this work was to validate the HOIM as …

Signal Subspace Processing In The Beam Space Of A True Time Delay Beamformer Bank, Nathan Allen Wilkins

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A number of techniques for Radio Frequency (RF) source location for wide bandwidth signals have been described that utilize coherent signal subspace processing, but often suffer from limitations such as the requirement for preliminary source location estimation, the need to apply the technique iteratively, computational expense or others. This dissertation examines a method that performs subspace processing of the data from a bank of true time delay beamformers. The spatial diversity of the beamformer bank alleviates the need for a preliminary estimate while simultaneously reducing the dimensionality of subsequent signal subspace processing resulting in computational efficiency. The pointing direction of …

Experimental Validation Of The Calphad Approach Applied To Multi-Principle Element Alloys, Nathan J. Bryant

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High entropy alloys (HEAs) are a recent area of research in materials science. Their namesake is because their high entropy of mixing due to multiple metallic elements in a near equimolar ratio. The high entropy of mixing is supposed to suppress unwanted, brittle, ordered intermetallic phases, and form a single, randomly mixed solid solution phase. This phenomena makes HEAs a good candidate for structural applications. However, this entropy of mixing may not be enough to suppress all intermetallic phases. For this reason, the CALculation of PHAse Diagrams (CALPHAD) approach is being explored to predict phase equilibrium in HEAs. This study …

Owl Query Answering Using Machine Learning, Todd Huster

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The formal semantics of the Web Ontology Language (OWL) enables automated reasoning over OWL knowledge bases, which in turn can be used for a variety of purposes including knowledge base development, querying and management. Automated reasoning is usually done by means of deductive (proof-theoretic) algorithms which are either provably sound and complete or employ approximate methods to trade some correctness for improved efficiency. As has been argued elsewhere, however, reasoning methods for the Semantic Web do not necessarily have to be based on deductive methods, and approximate reasoning using statistical or machine-learning approaches may bring improved speed while maintaining high …

Nano-Materials For Microwave And Terahertz Applications, Joshua Myers

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In this age of digital electronics the quest for faster computational devices and high speed communications have driven a need for new materials that are capable of fulfilling these goals. In both areas the need for a thinner channel in transistors, faster carrier transport characteristics, and better magnetic materials dominate the direction of research. Recently 2D materials have been realized. These single layer atomic thick materials show potential in having extremely high carrier transport velocities at room temperature and, due to their natural 2D structure, are the thinnest material possible in nature. On the other hand spin-spray ferrites have showed …

Silver Nanoparticles: The Immediate Benefits Of Low Bacterial Resistance And The Long-Term Risk Of Persistent Stress In Mammalian Cells, David Harold Ellis

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Silver nanoparticles (AgNPs) are the fastest growing sector of nanotechnology, due mostly to their antibacterial properties. The antibacterial effectiveness of AgNPs is well known and derives from the shedding of silver ions which have multiple antibacterial targets in the bacterial cell. Due to their continuous release of ions and demonstrated antibacterial potency, some predict that AgNPs have a low potential for resistance development, which would make them a valuable asset in wound management. The ability for AgNPs to cause oxidative imbalance in mammalian cells is also well known, but the potential long-term impact of such a stress has not been …

Whole-Lake Primary Production Calculator, Colin D. Leong

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This work describes an implementation of a model for estimation of both benthic and phytoplanktonic primary production in lakes. The web application makes use of interpolation techniques to allow estimates of primary production using values for photosynthesis/irradiance parameters at only 5 depths. These estimates compare favorably in accuracy with estimates using values listed at over one hundred depths. Validation of the implementation was done by comparison with primary production results from the Northern Temperate Lakes Long Term Ecological Research database.

Direction Of Arrival Estimation Using Wideband Spectral Subspace Projection, Majid Shaik

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Many areas such as Wireless Communication, Oil Mining, Radars, Sonar, and Seismic Exploration require the direction of arrival estimation (DOA) of wideband sources. Most existing wideband DOA estimation algorithms decompose the wideband signals into several narrowband frequency bins, followed by either focusing or transforming to a reference frequency bin, before estimating the DOAs. The focusing based methods are iterative and their performance is affected by the choice of preliminary DOA estimates and the number of source DOAs to be estimated. The existing method requiring transformation to a reference frequency bin exhibits spurious peaks in the spatial spectrum and is not …

Reducing Error Rates In Intelligence, Surveillance, And Reconnaissance (Isr) Anomaly Detection Via Information Presentation Optimization, Donald Glen Church

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In the ISR domain, time-critical decision-making and dealing with multiple information feeds places high demands on the human. When designing aids and tools, the decision maker must be taken into account. This research looks toward designing a decision aid based the personality type of the operator. The BFI is used to determine the impact of personality and decision aid type (graphical vs. textual) on performance. Results show Openness and Agreeableness to be the strongest single factors for decision aid impact on performance. A model was also developed to show how the human takes the information and relates it to a …

An Experimental Investigation On Friction And Scuffing Failure Of Lubricated Point Contacts, Sai Goutham Soma

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Scuffing failure is a catastrophic thermal failure mode induced by the extreme surface temperature of the contacting components. As two mechanical elements roll against each other with high sliding motion, the frictional heat flux elevates the surface temperature to exceed the critical limit, resulting in the welding of the surfaces. The relative motion then tears the welded surfaces apart, causing the damage. Scuffing failure has been an important failure mode for rolling machine elements such as bearings and gears in aerospace applications, owing to the very high operating speeds. Recently, this failure mode has extended to the automotive field, where …

Feature Extraction Using Dimensionality Reduction Techniques: Capturing The Human Perspective, Ashley B. Coleman

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The purpose of this paper is to determine if any of the four commonly used dimensionality reduction techniques are reliable at extracting the same features that humans perceive as distinguishable features. The four dimensionality reduction techniques that were used in this experiment were Principal Component Analysis (PCA), Multi-Dimensional Scaling (MDS), Isomap and Kernel Principal Component Analysis (KPCA). These four techniques were applied to a dataset of images that consist of five infrared military vehicles. Out of the four techniques three out of the five resulting dimensions of PCA matched a human feature. One out of five dimensions of MDS matched …

Integrated Magnetic Components For Rf Applications, Sheena Hussaini

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Integrated r-f passive components such as inductors, transmission lines, transformers etc, form the basic building blocks in r-f integrated circuits (RFICs) such as matching networks, low noise amplifiers (LNAs), synthesizers and r-f mixers. One main challenge faced by current technology developers in integrating r-f components on integrated chip (IC) are related to operation and size. Tremendous efforts were made for overcoming challenges of r-f integrated circuits to meet growing technology demands.

In general, r-f devices utilize magnetic materials such as ferrites for their operation for improving device performance and scaling. However, due to material properties and size ferrite materials are …

Design And Performance Analysis Of Magnetic Adder And 16-Bit Mram Using Magnetic Tunnel Junction Transistor, Surya Kiran Akkaladevi

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The scaling down of IC's based on CMOS technology faces significant challenges due to technology advancing factors. The stand-by power becomes comparable to active power due to the increasing leakage current. Power gating and various low-power schemes have been proposed in the past to reduce the stand-by power in CMOS designs. As most random access memory (RAM) used for primary storage in personal computers is volatile memory, which needs constant voltage (power on) to store the data and results in a higher stand-by power. Magnetic Tunnel Junctions (MTJ) transistor has feature of non-volatility, endurance and high density, which makes it …

Anterior Cruciate Ligament Biomechanics, Computational Modeling Of Mechanical Behavior And Injury Risk, Bharadwaj Cheruvu

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Knee joint involves interactions from various structures such as cartilage, bone, muscles, ligaments, tendon, as well as neural control. Anterior cruciate ligament (ACL) tears are one of the most frequent soft tissue injuries of the knee. A torn ACL leaves the joint unstable and at risk for further damage to other soft tissues manifested as pain, dislocation, and osteoarthritis. This injury is quite common in sports such as basketball, soccer and football. Females often tear their ACL 2-8 times more frequently than their male counterparts. An ACL injury can be devastating and significantly increases the athlete's risk for osteoarthritis long …

An Improved Adaptive Filtering Approach For Removing Artifact From The Electroencephalogram, Justin Ronald Estepp

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The biophysics of volume conduction that enable electrophysiological data acquisition also result in the mixing of data sources including possible, undesirable noise sources at the electrode interface. This work specifically focuses on improving the performance of the recursive least-squares (RLS) adaptive filtering method for removing eye movement artifact from the electroencephalogram. In biophysically-inspired simulated data, the RLS algorithm is verified to produce results that are inferior to extended infomax independent component analysis (ICA), the most widely used artifact correction approach in this problem space, due to its non-linear filter phase response and the presence of bidirectional contamination, or cross-talk, resultant …

Hierarchical Porous Structures With Aligned Carbon Nanotubes As Efficient Adsorbents And Metal-Catalyst Supports, Hema Vijwani

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The overall goal of this study is two-fold: synthesis of multiscale nanostructures by growing aligned carbon nanotubes on porous foam substrates and investigation of their applicability as adsorbents and catalyst supports for environmental remediation applications. High purity, vertically-aligned arrays of carbon nanotubes (CNT) are grown on open-cell interconnected porous carbon foams by pre-activating them with an oxide buffer layer followed by chemical vapor deposition (CVD). This type of hierarchical morphology provides the capability of increasing surface area by several orders of magnitude, while tuning its morphology for targeted applications. Analytical models are also proposed in this study for specific surface …