Engineering Commons^™

Rf Cmos Band Pass Filters With Wide Tuning Frequency, Controllable Pass Band And High Stopband Rejection: Using Passive And Active Inductors, Jian Chen

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With the increasing demand for high performance RF front-end modules, like multimedia handset and base station devices accommodating multiple wireless standards (2G, 2.5G, 3G, WiMAX, and LTE). Multiple IF amplifiers, mixers, RF band pass filters (BPFs), modulators and demodulators are desired to be tunable to meet dynamic standards with different frequency bands. Tunable devices with wide tuning frequency range, tuning speed, high linearity, energy conservative, high pass band gain, high stop band rejection are the paramount components in the reconfigurable RF front-end systems. In this dissertation, first a wide tuning passive inductor band pass filter (BPF) with steep roll-off high …

Tunable C Band Coupled-C Bpf With Resonators Using Active Capacitor And Inductor, Yu Wang

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In this thesis, a classic second-order coupled-capacitor Chebyshev bandpass filter with resonators using active capacitor and inductor is presented. The low cost and small size of CMOS active components makes the band pass filter (BPF) attractive in fully-integrated CMOS applications. The active capacitor is designed to compensate active inductor's resistance for resistive match in the resonator. Meanwhile, adjusting design parameter of the active component provides BPF tunability in center frequency, pass band and pass band gain. Designed in 1.8V 180 nanometer CMOS process, the BPF has a tuning frequency range of 758-864 MHz, a controllable pass band of 7.1-65.9 MHz, …

Vehicle Level Transient Aircraft Thermal Management Modeling And Simulation, Adam Donovan

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Many advances in technology are expected to increase the capabilities of next generation aircraft, and these advances will increase the thermal load on the aircraft as well. In order to assess and account for these increased thermal loads, three studies were performed: a fuel pump trade study, a high energy pulsed system (HEPS) implementation study, and a legacy vehicle environmental control system (ECS) study. The fuel pump study addresses the effect of the implementation of a centrifugal fuel pump versus a variable displacement fuel pump. Traditionally, aircraft designers have used a centrifugal fuel pump over a piston based pump based …

Development, Design, Manufacture And Test Of Flapping Wing Micro Aerial Vehicles, Todd J. Smith

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The field of FlappingWing Micro Air Vehicles (FWMAV) has been of interest in recent years and as shown to have many aerodynamic principles unconventional to traditional aviation aerodynamics. In addition to traditional manufacturing techniques, MAVs have utilized techniques and machines that have gained significant interest and investment over the past decade, namely in additive manufacturing. This dissertation discusses the techniques used to manufacture and build a 30 gram-force (gf) model which approaches the lower limit allowed by current commercial off-the-shelf items. The vehicle utilizes a novel mechanism that minimizes traditional kinematic issues associated with four bar mechanisms for flapping wing …

Compressed Sensing For Electronic Radio Frequency Receiver: Detection, Sensitivity, And Implementation, Ethan Lin

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The current state-of the-art for digital receiver bandwidth coverage is now reaching multi-GHz. The conventional wideband digital receiver design is based on the Nyquist information theory, and its bandwidth coverage is limited by the Nyquist sampling rate. Therefore, receiver performance highly depends on the high speed analog-to-digital (ADC) technology and computation hardware such as FPGA. Having proved a fundamental theory that Nyquist waveform can be restored with a reduced sampling rate under certain situations, compressed sensing (CS) technique becomes an attractive solution to wideband digital receiver development.

In this dissertation, performance analysis of the compressed sensing in receiver application is …

Leaky Wave Antenna, Pradyumna Aditya

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The main radiation mechanism in a leaky wave antenna is a travelling wave in a guided structure. The main characteristics of a leaky wave antenna are: light weight, easy to fabricate. Leaky wave antennas have been in use since the 1940s. In this thesis, a portable and powerful leaky-wave antenna is designed, implemented, and demonstrated for scanning application. We change the guiding structure by applying a high dielectric constant material to produce a low-cost, small size, light weight, and high sensitivity leaky-wave antenna. The designed antenna can reach large scan angles with small frequency tuned. High scanning angles can be …

The Development Of A Human Operator Informatic Model (Hoim) Incorporating The Effects Of Non-Invasive Brain Stimulation On Information Processing While Performing Multi-Attribute Task Battery (Matb), Justin Nelson

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Multitasking has become an integral attribute associated with military operations in tasks such as cyber defense operators, remotely piloted aircraft (RPA) operators and air traffic controllers. These tasks are monotonous and repetitive in nature requiring the human operator to interpret and process information that may exceed their mental capability. When the human operator can no longer effectively process and respond to the critical incoming information, an asymptotic limit known as the multitasking throughput capacity (MTC) will be present. At this point, critical target detection and reaction times may degrade resulting in a decrement in performance. The objective of this research …

An Approach To Implement Kahn's Technique With Dynamic Power Supply, Sowjanya Kommu

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Radio-frequency power amplifiers are an integral part of today's communication systems. Primary importance is given to improve its efficiency and linearity, which are required for the effective signal transmission. Three main architectures on which, the efficiency of communication systems are based on are: (a) Kahn's technique, (b) Doherty's power amplifiers, and (c) Cheireix out-phasing modulation. Several schemes to implement these techniques exist in literature and their study is very diverse. In this thesis, a detailed literature survey on these techniques is presented, which includes their operation, properties, advantages, disadvantages, and areas of potential applications. This main objective of this thesis …

Personalized And Adaptive Semantic Information Filtering For Social Media, Pavan Kapanipathi

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Social media has experienced immense growth in recent times. These platforms are becoming increasingly common for information seeking and consumption, and as part of its growing popularity, information overload pose a significant challenge to users. For instance, Twitter alone generates around 500 million tweets per day and it is impractical for users to have to parse through such an enormous stream to find information that are interesting to them. This situation necessitates efficient personalized filtering mechanisms for users to consume relevant, interesting information from social media. Building a personalized filtering system involves understanding users' interests and utilizing these interests to …

Aligned Carbon Nanotube Carpets On Carbon Substrates For High Power Electronic Applications, Betty Tun-Huan Quinton

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Abstract Quinton, Betty Tun-Huan. Ph.D., Engineering Ph.D. Program, Wright State University, 2016. Aligned Carbon Nanotube Carpets On Carbon Substrates for High Power Electronic Applications. One of the driving forces behind nanotechnology research is the miniaturization of electronic devices. Electrical and thermal transport properties of device materials at micrometer and nanometer scales become very important in such applications. Carbon materials, especially carbon nanotubes (CNTs), have exceptionally low density and superior electrical, thermal, and mechanical properties. Vertically aligned CNTs attached to lightweight carbon substrates may hold the key to fully use these outstanding properties. However, the majority of studies reported to date …

Detecting Php-Based Cross-Site Scripting Vulnerabilities Using Static Program Analysis, Steven M. Kelbley

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With the widespread adoption of dynamic web applications in recent years, a number of threats to the security of these applications have emerged as significant challenges for application developers. The security of developed applications has become a higher priority for both developers and their employers as cyber attacks become increasingly more prevalent and damaging. Some of the most used web application frameworks are written in PHP and have become major targets due to the large number of servers running these applications worldwide. A number of tools exist to evaluate PHP code for issues, however most of these applications are not …

Data Mining And Mathematical Models For Direct Market Campaign Optimization For Fred Meyer Jewelers, Lebin Lin

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Jewelry retail companies like Fred Meyer Jewelers employ direct marketing such as mailing lists and catalogs as a primary means to promote products, maintain customer relationships, and drive sale growths. Most jewelry customers, however, do not purchase frequently – they make only a limited number of purchases at special times with long lead-times between purchases. This has created a series of challenging problems for the marketing team at these jewelry stores in a) predicting when and what the customer purchases, and b) deciding what customers to be targeted so as to maximize the return on investment in the design of …

Miniatured Inertial Motion And Position Tracking And Visualization Systems Using Android Wear Platform, Dhruvkumar Navinchandra Patel

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In this thesis, we have designed and developed a motion tracking and visualization system using the latest motion tracking sensory technologies. It is one of the enabling technologies for our novel visual-inertial odometer and human anatomy based 3D Locating, Mapping and Navigation system for endoscopy and drug delivery capsules used inside GI tract. In particular, we have: i) designed and completed a cloud-based sensory data collecting, processing and storage system to provide the reliable computing and storage platform; ii) explored different data processing methods to obtain improved-quality motion results from extremely noisy raw data, e.g., by using a low pass …

Low-Cost, Wireless Optical Oximeter For Monitoring Of Brain Function In High-Risk Pediatric Population, Zahra Meghjani

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Nearly 4 million neonates die every year due to brain injuries, most caused by hypoxia. Neonatal ICU requires newborns with critical health conditions to be monitored continuously calling for the need of a non-invasive, compact and portable device. However, commercial devices are mostly bulky and/or expensive. The neonatal mortality is higher in under-developed countries, where such expensive and large devices are not affordable. Hence, my thesis focuses on building first generation compact, inexpensive, and wireless device that can monitor and provide feedback to clinicians during intervention. This approach is based on light absorption by oxy- and deoxy-hemoglobin chromophores. The total …

Development Of Analytical Equations For Optimum Tilt Of Two-Axis And Single-Axis Rotating Solar Panels For Clear-Atmosphere Condition, Gaurav Subhash Gugale

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Solar Energy is a renewable energy source which is used widely in recent times. Photovoltaic panels collect the sun’s energy and convert it to electricity. Photovoltaic panels are being widely used in both domestic applications, commercial applications, and small-scale power generation applications. Photovoltaic panels are easy to install, they generate most of their power when electrical demands peak, prices of photovoltaic panels are dropping rapidly, photovoltaic panels require low maintenance, their operating costs are minimal, and they are highly suitable for remote applications. The amount of electricity produced by photovoltaic panels depends on the amount of sunlight the panel captures. …

Modification Reactivity Analysis Of Human Replication Protein A In Biologically Important States, Ryan James Yoakum

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Human Replication Protein A (RPA) is a heterotrimeric protein consisting of 70, 32, and 14 kDa subunits. RPA is the predominant single stranded DNA binding protein within the cell. It is involved in all forms of the DNA metabolic pathways, including but not limited to, replication, recombination, damage repair, as well as cell cycle and DNA check point signaling. RPA is phosphorylated (pRPA) during G1-S phase and is dephosphorylated during M phase. Further, RPA is hyperphosphorylated during DNA damage. Through the use of x-ray crystallography and nuclear magnetic resonance, researchers have proposed models and structures based on truncated portions of …

A Closed Loop Research Platform That Enables Dynamic Control Of Wing Gait Patterns In A Vertically Constrained Flapping Wing - Micro Air Vehicle, Hermanus Van Botha

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Research in Flapping Wing - Micro Air Vehicles(FW-MAVs) has been growing in recent years. Work ranging from mechanical designs to adaptive control algorithms are being developed in pursuit of mimicking natural flight. FW-MAV technology can be applied in a variety of use cases such a military application and surveillance, studying natural ecological systems, and hobbyist commercialization. Recent work has produced small scale FW-MAVs that are capable of hovering and maneuvering. Researchers control maneuvering in various ways, some of which involve making small adjustments to the core wing motion patterns (wing gaits) which determine how the wings flap. Adaptive control algorithms …

An Autoencoder-Based Image Descriptor For Image Matching And Retrieval, Chenyang Zhao

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Local image features are used in many computer vision applications. Many point detectors and descriptors have been proposed in recent years; however, creation of effective descriptors is still a topic of research. The Scale Invariant Feature Transform (SIFT) developed by David Lowe is widely used in image matching and image retrieval. SIFT detects interest points in an image based on Scale-Space analysis, which is invariant to change in image scale. A SIFT descriptor contains gradient information about an image patch centered at a point of interest. SIFT is found to provide a high matching rate, is robust to image transformations; …

Use Of Eeg To Understand Brain Intensity In Engineering Students Using A Stem Educational Mobile Application, Kevin Hatcher

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In the first two years of undergraduate work in engineering, students are taught concepts such as physics, electronics, and most importantly calculus. It is especially important for students to get a better grasp on foundational math concepts, such as calculus in the beginning or they will be overwhelmed by the workload to come. The focus of this research was to understand how students learning calculus, could benefit from an augmented-educational mobile application. In the study students were measured with electroencephalography (EEG) measurements utilized by the Emotive EPOC® as they attempted to solve different limit themed problems in order to determine …

Locally Optimized Covariance Kriging For Non-Stationary System Responses, Daniel Lee Clark Jr.

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In this thesis, the Locally-Optimized Covariance (LOC) Kriging method is developed. This method represents a flexible surrogate modeling approach for approximating a non-stationary Kriging covariance structures for deterministic responses. The non-stationary covariance structure is approximated by aggregating multiple stationary localities. The aforementioned localities are determined to be statistically significant utilizing the Non-Stationary Identification Test. This methodology is applied to various demonstration problems including simple one and two-dimensional analytical cases, a deterministic fatigue and creep life model, and a five-dimensional fluid-structural interaction problem. The practical significance of LOC-Kriging is discussed in detail and is directly compared to stationary Kriging considering computational …

Analyzing Cognitive Workload Through Eye-Related Measurements: A Meta-Analysis, Melissa Patricia Coral

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Understanding cognitive workload has become a vital topic for researchers in developing future systems. Existing research has investigated the use of physiological measurements of the eye with cognitive workload, though a quantitative synthesis has yet to be performed. A meta-analysis was conducted to examine the effects of cognitive workload on eye-related measurements. The objective of this meta-analysis is not to determine a difference between the levels of workload, but to identify reliable measurements. Measurements through blinks, saccades, pupils, and fixations were examined. Twenty-two studies, contributing to a total of sixty entries, met the appropriate inclusion criteria for the meta-analysis. Findings …

Extension Of Multivariate Analyses To The Field Of Microbial Ecology, Vijay Shankar

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Ground-breaking advancements in molecular and analytical techniques in the past decade have enabled researchers to accumulate data at an extraordinary rate. Especially in the field of microbial ecology, the introduction of technologies such as high-throughput sequencing, quantitative microarrays, nuclear magnetic resonance and mass spectrometry has led to the interrogation of diverse and previously unexplored microbial communities at unparalleled depth. Analysis and interpretation of patterns within datasets acquired with such high-throughput methods require powerful statistical approaches. A class of such techniques called multivariate statistical analyses is an excellent choice for analysis of complex microbiota-related datasets. This field of statistics is constantly …

Thermoelectric Transport And Energy Conversion Using Novel 2d Materials, Luke J. Wirth

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Nanomaterials hold great promise for applications in thermal management and thermoelectric power generation. Defects in these are important as they are generally inevitably introduced during fabrication or intentionally engineered to control the properties of the nanomaterials. Here, we investigate how phonon-contributed thermal conductance in narrow graphene, boron nitride (BN), and silicene nanoribbons (NRs), responds to the presence of a vacancy defect and the corresponding geometric distortion, from first principles using the non-equilibrium Green's function method. Analyses are made of the geometries, phonon conductance coefficients, and local densities of states (LDOS) of pristine and defected nanoribbons. It is found that hydrogen …

Intelligent Caching To Mitigate The Impact Of Web Robots On Web Servers, Howard Nathan Rude

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With an ever increasing amount of data that is shared and posted on the Web, the desire and necessity to automatically glean this information has led to an increase in the sophistication and volume of software agents called web robots or crawlers. Recent measurements, including our own across the entire logs of Wright State University Web servers over the past two years, suggest that at least 60\% of all requests originate from robots rather than humans. Web robots display different statistical and behavioral patterns in their traffic compared to humans, yet present Web server optimizations presume that traffic exhibits predominantly …

De-Anonymization Attack Anatomy And Analysis Of Ohio Nursing Workforce Data Anonymization, Jacob M. Miracle

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Data generalization (anonymization) is a widely misunderstood technique for preserving individual privacy in non-interactive data publishing. Easily avoidable anonymization failures are still occurring 14 years after the discovery of basic techniques to protect against them. Identities of individuals in anonymized datasets are at risk of being disclosed by cyber attackers who exploit these failures. To demonstrate the importance of proper data anonymization we present three perspectives on data anonymization. First, we examine several de-anonymization attacks to formalize the anatomy used to conduct attacks on anonymous data. Second, we examine the vulnerabilities of an anonymous nursing workforce survey to convey how …

Transient Analysis Of A Solid Oxide Fuel Cell/ Gas Turbine Hybrid System For Distributed Electric Propulsion, Venkata Adithya Chakravarthula

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Gas turbine technology for aerospace applications are approaching limits in efficiency gains as increases in efficiency today occurs in very small increments. One limitation in conventional gas turbine technology is the combustion process, which destroys most of the exergy in the cycle. To address this limitation in a traditional Brayton power cycle, a hybrid system which is integrated with Solid Oxide Fuel Cell (SOFC) and gas turbine is developed. Hybrid systems involving fuel cells have better efficiencies than conventional power generation systems. Power generation systems with improved performance from low fuel utilizations and low maintenance costs are possible. The combination …

Characterization Of Peripheral Lung Lesions By Statistical Image Processing Of Endobronchial Ultrasound Images, Aaron T. Madaris

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This thesis introduces the concept of implementing greyscale analysis, also known as intensity analysis, on endobronchial ultrasound (EBUS) images for the purposes of diagnosing peripheral lung tumors. The statistical methodology of using greyscale and histogram analysis allows the characterization of lung tissue in EBUS images. Regions of interest (ROI) will be analyzed in MATLAB and a feature vector will be created. A feature vector of first-order, second-order and histogram greyscale analysis will be created and used for the classification of malignant vs benign peripheral lung tumors. The tools that were implemented were MedCalc for the initial statistical analysis of receiver …

Identifying Offensive Videos On Youtube, Rajeshwari Kandakatla

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Harassment on social media has become a critical problem and social media content depicting harassment is becoming common place. Video-sharing websites such as YouTube contain content that may be offensive to certain community, insulting to certain religion, race etc., or make fun of disabilities. These videos can also provoke and promote altercations leading to online harassment of individuals and groups. In this thesis, we present a system that identifies offensive videos on YouTube. Our goal is to determine features that can be used to detect offensive videos efficiently and reliably. We conducted experiments using content and metadata available for each …

Computer Graphics And Visualization Based Analysis And Record System For Hand Surgery And Therapy Practice, Venkatamanikanta Subrahmanyakartheek Gokavarapu

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In this thesis, we have designed and developed a computer graphics and visualization based analysis and record system for hand surgery and therapy practice. In particular, we have designed and developed three novel technologies: (i) model-based data compression for hand motion records (ii) model-based surface area estimation of a human hand and (iii) an emulated study of hand wound area estimation. First, we have presented a new data compression technique to better address the needs of electronic health record systems, such as file storage and privacy. In our proposed approach, we will extract the patient's hand motion information and store …

Evaluation Of Real-Time Adaptive Display Systems In A Pilot Training Environment, Jerred Charles Holt

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The Air Force (AF) has traditionally utilized a frequency-based approach that relies on after-action review for feedback to train their pilots. The goal of this study is to evaluate the effectiveness of adding real-time adaptive supplemental feedback to this approach. A synthetic task environment was developed to emulate the current AF training platform. Supplemental HUD displays were developed that captured various degrees of expertise at the flight task, thereby serving as a both training and performance aids. Varied presentation schedules for these supplemental displays and triggers for their dynamic behavior were compared and evaluated based on performance, knowledge and workload …