Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 60 of 92

Full-Text Articles in Engineering

Vehicle Level Transient Aircraft Thermal Management Modeling And Simulation, Adam Donovan Jan 2016

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

Browse all Theses and Dissertations

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 …


Knowledge-Driven Implicit Information Extraction, Pathirage Dinindu Perera Jan 2016

Knowledge-Driven Implicit Information Extraction, Pathirage Dinindu Perera

Browse all Theses and Dissertations

Natural language is a powerful tool developed by humans over hundreds of thousands of years. The extensive usage, flexibility of the language, creativity of the human beings, and social, cultural, and economic changes that have taken place in daily life have added new constructs, styles, and features to the language. One such feature of the language is its ability to express ideas, opinions, and facts in an implicit manner. This is a feature that is used extensively in day to day communications in situations such as: 1) expressing sarcasm, 2) when trying to recall forgotten things, 3) when required to …


Tunable C Band Coupled-C Bpf With Resonators Using Active Capacitor And Inductor, Yu Wang Jan 2016

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

Browse all Theses and Dissertations

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, …


Rf Cmos Band Pass Filters With Wide Tuning Frequency, Controllable Pass Band And High Stopband Rejection: Using Passive And Active Inductors, Jian Chen Jan 2016

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

Browse all Theses and Dissertations

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 …


1-Ghz Cmos Analog Signal Squaring Circuit, Lizhong He Jan 2016

1-Ghz Cmos Analog Signal Squaring Circuit, Lizhong He

Browse all Theses and Dissertations

In analog signal processing the squaring circuit represents the core for implementing an analog signal having a value representing the square of the input signal. For example, calculating the square of input signal is necessary in adaptive processing of an input signal based on its instantaneous root mean square value. In this thesis, a new 1-Ghz analog signal squaring circuit (squarer) designed in 180 nanometer CMOS process is presented. It is implemented by CMOS components including current source, current mirror, differential amplifier, low-pass filter, and voltage output buffer. A gain control amplifier and a 10-bit ADC are set up to …


Leaky Wave Antenna, Pradyumna Aditya Jan 2016

Leaky Wave Antenna, Pradyumna Aditya

Browse all Theses and Dissertations

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 …


Fpga Realization Of Low Register Systolic Multipliers Over Gf(2^M), Qiliang Shao Jan 2016

Fpga Realization Of Low Register Systolic Multipliers Over Gf(2^M), Qiliang Shao

Browse all Theses and Dissertations

Finite field multiplication over GF(2^m) is a critical component for elliptic curve cryptography (ECC). National Institute of Standards and Technology (NIST) has recommended five polynomials (two trinomials and three pentanomials) for ECC implementation. Although there are a lot reports available on polynomial basis multipliers, efficient implementation of a design with flexible field-size is quite rare. There is another basis to represent the field called normal basis. Normal basis multiplication over GF(2^m) is widely used in various applications such as elliptic curve cryptography (ECC). As a special class of normal basis with low complexity, Gaussian normal basis (GNB) has received considerable …


Inlet Distortion Effects On The Unsteady Aerodynamics Of A Transonic Fan Stage, Daniel Oliver Reilly Jan 2016

Inlet Distortion Effects On The Unsteady Aerodynamics Of A Transonic Fan Stage, Daniel Oliver Reilly

Browse all Theses and Dissertations

A computational study was conducted to understand the influence of aircraft inlet distortion flow on the unsteady aerodynamic loading of a gas turbine fan stage. A single stage, transonic fan design with no inlet guide vanes was modeled with a commercial, computational fluid dynamics solver, STAR-CCM+, using the harmonic balance technique. The baseline inlet boundary condition applied to the model is consistent with that of a homeomorphic variant of the M2129 S-duct, and exhibited stagnation pressure distortion and a swirl pattern. The baseline inlet flow was decomposed and parameterized into a set of inlet boundary conditions which were individually applied …


Engineering Healthcare Delivery: A Systems Engineering Approach To Improving Trauma Center Nursing Efficacy, Robert A. Myers Jan 2016

Engineering Healthcare Delivery: A Systems Engineering Approach To Improving Trauma Center Nursing Efficacy, Robert A. Myers

Browse all Theses and Dissertations

The efficacy of nurses is impacted by their availability to their patients and the occurrence of both beneficial and detrimental interruptions. Using system engineering tools, this work addresses open challenges in (i) methods for effective matching of nurse availability to non-stationary stochastic demand, (ii) differentiation of beneficial and detrimental interruptions, and (iii) modeling of nurses’ work with interruptions to provide an objective method of testing interruption interventions. First, we propose both qualitative and quantitative approaches to evaluate and then model the impact of resource scheduling on patient wait time in a Level I trauma center for a highly specialized nurse, …


Data Mining And Mathematical Models For Direct Market Campaign Optimization For Fred Meyer Jewelers, Lebin Lin Jan 2016

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

Browse all Theses and Dissertations

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 …


Fuzzy Control Of A Hyperloop Mass Transit System, Joseph D. Plantz Jan 2016

Fuzzy Control Of A Hyperloop Mass Transit System, Joseph D. Plantz

Browse all Theses and Dissertations

Fuzzy logic control of a Hyperloop is carried out in this thesis. Hyperloop is being described hypothetically as a fifth mode of mass transportation and is a registered trademark of Space Exploration Technologies Corporation (SpaceX). To inspire others to help in its development and make it a reality, the Hyperloop is being explored as open-source technology by SpaceX. In this thesis a near friction-less track is constructed and is fixed inside a tunnel. External fans are used to produce air pressure inside the tunnel to propel the vehicle down the track. Fuzzy Logic Control is used to stop the vehicle …


High-Fidelity Multidisciplinary Sensitivity Analysis For Coupled Fluid-Solid Interaction Design, Koorosh Gobal Jan 2016

High-Fidelity Multidisciplinary Sensitivity Analysis For Coupled Fluid-Solid Interaction Design, Koorosh Gobal

Browse all Theses and Dissertations

In many engineering disciplines such as aerospace, marine, automotive, and biomedical engineering, the consideration of the coupling between the fluid and structural systems is necessary for quality engineering analysis. Therefore, the need for such analysis in the design is continuously increasing. The primary motivation for this work is to develop a sensitivity analysis tool that is capable of calculating accurate sensitivities without significant modification of the source codes for simulations based on non-body conformal grids. The majority of work done on the coupled fluid-solid simulations are based on computational grids that conform to solid boundaries. This becomes a restriction for …


Miniatured Inertial Motion And Position Tracking And Visualization Systems Using Android Wear Platform, Dhruvkumar Navinchandra Patel Jan 2016

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

Browse all Theses and Dissertations

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 …


Thermoelectric Transport And Energy Conversion Using Novel 2d Materials, Luke J. Wirth Jan 2016

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

Browse all Theses and Dissertations

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 …


The Design And Experimental Investigation Of Novel Double-Blade Wind Turbine Models Inspired By Houck's Concept, Laura E. Carpenter Jan 2016

The Design And Experimental Investigation Of Novel Double-Blade Wind Turbine Models Inspired By Houck's Concept, Laura E. Carpenter

Browse all Theses and Dissertations

Energy can be captured from wind turbines efficiently today. However there's always room for improvement up to the Betz's limit of 59.3% efficiency. A novel wind turbine blade was designed with double blade rotor inspired by Houck's concept in an attempt to improve the efficiency of the horizontal axis wind turbine. Scaled wind turbine models with a diameter of 150 mm were designed in SolidWorks adjusting the parameters of stagger, gap, and decalage. The general design comprises of two modern blades attached by a curved flow guide at the tip. Fourteen blade models were designed and tested to obtain power, …


Educational Methods For Inverted-Lecture Computer Science And Engineering Classrooms To Overcome Common Barriers To Stem Student Success, Kathleen Timmerman Jan 2016

Educational Methods For Inverted-Lecture Computer Science And Engineering Classrooms To Overcome Common Barriers To Stem Student Success, Kathleen Timmerman

Browse all Theses and Dissertations

New educational pedagogies are emerging in an effort to increase the number of new engineers available to enter the workforce in the coming years. One of the re-occurring themes in these pedagogies is variations of the flipped classroom. Often the additional classroom time gained from flipping is used to reinforce learning objectives. It is hypothesized that it might be more beneficial to students if a portion of that time is used to address common non-cognitive barriers that prevent students from succeeding in the major. In a freshman Introductory Computer Science course, three different pedagogies are compared: a hybrid lecture-active learning …


Low-Cost, Wireless Optical Oximeter For Monitoring Of Brain Function In High-Risk Pediatric Population, Zahra Meghjani Jan 2016

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

Browse all Theses and Dissertations

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 …


De-Anonymization Attack Anatomy And Analysis Of Ohio Nursing Workforce Data Anonymization, Jacob M. Miracle Jan 2016

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

Browse all Theses and Dissertations

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 …


Elucidating The Role Of Microstructure, Texture, And Microtexture On The Dwell Fatigue Response Of Ti-6al-4v, Alec Mitchell Blankenship Jan 2016

Elucidating The Role Of Microstructure, Texture, And Microtexture On The Dwell Fatigue Response Of Ti-6al-4v, Alec Mitchell Blankenship

Browse all Theses and Dissertations

Ambient temperature dwell sensitivity is known to be deleterious to the fatigue response of near-alpha titanium alloys. Dwell fatigue refers to the presence of a sustained hold at peak stress as opposed to the continuous variation of normal cyclic fatigue loading. This reduction in failure life-times from dwell loading is attributed to early crack nucleation and faster crack propagation. The degradation is the result of plastic anisotropy on the microstructural scale along with tendency of titanium alloys to creep at low temperatures at stresses well below the 0.2% offset yield strength. Despite being the most widely used titanium alloy, Ti-6Al-4V …


Computer Modeling Of A Solar Thermal System For Space Heating, Dhananjay D. Deshpande Jan 2016

Computer Modeling Of A Solar Thermal System For Space Heating, Dhananjay D. Deshpande

Browse all Theses and Dissertations

Most applications of flat plate, low-temperature solar thermal panels are for water heating, such as producing domestic hot water or raising the temperature of swimming pools. This is reasonable given that the large masses of water present in these systems inherently provide built-in thermal energy storage so that a separate energy storage tank does not have to be purchased. For a space heating system, extra thermal energy storage generally has to be purchased and is a detriment to the economics of these systems. Despite the economic drawbacks of solar thermal space heating, this thesis focuses on the size of thermal …


A Hybrid Approach To Aerial Video Image Registration, Karol T. Salva Jan 2016

A Hybrid Approach To Aerial Video Image Registration, Karol T. Salva

Browse all Theses and Dissertations

Many video processing applications, such as motion detection and tracking, rely on accurate and robust alignment between consecutive video frames. Traditional approaches to video image registration, such as pyramidal Kanade-Lucas-Tomasi (KLT) feature detection and tracking are fast and subpixel accurate, but are not robust to large inter-frame displacements due to rotation, scale, or translation. This thesis presents an alternative hybrid approach using normalized gradient correlation (NGC) in the frequency domain and normalized cross-correlation (NCC) in the spatial domain that is fast, accurate, and robust to large displacements. A scale space search is incorporated into NGC to enable more consistent recovery …


A Fractal-Based Mathematical Model For Cancellous Bone Growth Considering The Hierarchical Nature Of Bone, Stephanie Marie Suhr Jan 2016

A Fractal-Based Mathematical Model For Cancellous Bone Growth Considering The Hierarchical Nature Of Bone, Stephanie Marie Suhr

Browse all Theses and Dissertations

The hierarchical structure of bone alone is not comprehensive enough to provide morphological explanation of how the size and arrangement of the trabeculae within cancellous bone affect load distribution, particularly concerning deterioration of bone in elderly patients. The collagen network and hydroxyapatite play a large role in defining the shape of trabeculae in cancellous bone despite that the arrangement and size is seemingly random. The growth of plates and rods in cancellous bone is mainly due to loading and stress lines within the bone, but mathematical predictive models can be developed using fractal analysis to show how bone may grow …


Intelligent Caching To Mitigate The Impact Of Web Robots On Web Servers, Howard Nathan Rude Jan 2016

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

Browse all Theses and Dissertations

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 …


Implementation Of Logic Fault Tolerance On A Dynamically Reconfigurable Fpga, Kiran Jayarama Jan 2016

Implementation Of Logic Fault Tolerance On A Dynamically Reconfigurable Fpga, Kiran Jayarama

Browse all Theses and Dissertations

Relative to integrated circuit (IC) systems, on-chip fault detection entails determi- nation of whether or not a fault exists. The cause of the fault could be some faulty logic resource or some faulty interconnect (wiring) resource, but typically, fault detection only determines if a fault exists, not what exactly is faulty. Beyond pure fault detection some work has been done relative to on-chip fault analysis to fur- ther determine not only if a fault exists, but exactly what is faulty. Even less work has been done to actually tolerate faulty resources once they have been found. For this work, we …


Transient Analysis Of A Solid Oxide Fuel Cell/ Gas Turbine Hybrid System For Distributed Electric Propulsion, Venkata Adithya Chakravarthula Jan 2016

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

Browse all Theses and Dissertations

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 …


Development Of Analytical Equations For Optimum Tilt Of Two-Axis And Single-Axis Rotating Solar Panels For Clear-Atmosphere Condition, Gaurav Subhash Gugale Jan 2016

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

Browse all Theses and Dissertations

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. …


Development, Design, Manufacture And Test Of Flapping Wing Micro Aerial Vehicles, Todd J. Smith Jan 2016

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

Browse all Theses and Dissertations

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 …


Identifying Offensive Videos On Youtube, Rajeshwari Kandakatla Jan 2016

Identifying Offensive Videos On Youtube, Rajeshwari Kandakatla

Browse all Theses and Dissertations

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 …


Optical Redox Imaging Of Metabolic Activity, Syed Anwar Hyder Zaidi Jan 2016

Optical Redox Imaging Of Metabolic Activity, Syed Anwar Hyder Zaidi

Browse all Theses and Dissertations

Fluorescence imaging can be used to determine tissue metabolism, which is an indication of the cellular functionality. Metabolic contrast is useful for the early detection of several medical conditions such as cancer, diabetes, lung diseases etc. This study aims to use fluorescence imaging to quantify NADH and FAD, which are cellular metabolic indicators. A parameter known as Redox ratio, can be used to study metabolic state of several tissue types and disease states. To quantify the Redox ratio, three fluorescence imaging systems were optimized to measure the fluorescence signal from NADH and FAD. The first system was a camera based …


Early Assessment Of Burn Severity In Human Tissue With Multi-Wavelength Spatial Frequency Domain Imaging, Chien Sing Poon Jan 2016

Early Assessment Of Burn Severity In Human Tissue With Multi-Wavelength Spatial Frequency Domain Imaging, Chien Sing Poon

Browse all Theses and Dissertations

Burn injuries such as thermal burns, which are caused by contact with flames, hot liquids, hot surfaces, and other sources of high heat as well as chemical burns and electrical burns, affects at least 500,000 people in the United States, to which 45,000 of them require medical treatment and 3,500 of them result in death. It has also been reported that in the United States alone, fire results in a death approximately every three hours and an injury every 33 minutes. Early knowledge about burn severity can lead to improved outcome for patients. In this study, the changes in optical …