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Masters Theses

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Full-Text Articles in Engineering

Emc Performance Evaluation Of Various Pcb Designs Through Simulation And Measurements, Dimitri Häring Aug 2019

Emc Performance Evaluation Of Various Pcb Designs Through Simulation And Measurements, Dimitri Häring

Masters Theses

The applied research presented in this thesis is intended to deepen the understanding of various concepts related to PCB design with respect to EMC and RF performance. The first topic addressed is embedded capacitance of a PCB. The work includes decoupling capacitors and their placement relative to the IC in a combination of three different PCB stack-ups. The evaluation is performed in the frequency domain and time domain. The next topic discussed is the EMC/ EMI filters which are essential measurements to protect a device or subsystem from EMI. The circuit's load is usually unknown. A generic filter design ...


Developing 5gl Concepts From User Interactions, David Stuckless Meyer Jul 2019

Developing 5gl Concepts From User Interactions, David Stuckless Meyer

Masters Theses

In the fulfilling of the contracts generated in Test Driven Development, a developer could be said to act as a constraint solver, similar to those used by a 5th Generation Language(5GL). This thesis presents the hypothesis that 5GL linguistic mechanics, such as facts, rules and goals, will be emergent in the communications of developer pairs performing Test Driven Development, validating that 5GL syntax is congruent with the ways that practitioners communicate. Along the way, nomenclatures and linguistic patterns may be observed that could inform the design of future 5GL languages.


A Fea/Cfd Study Of Heat Transfer To Semi-Trailer Disc Brake Wheel-End Components During A Braking Event, Justin P. Fisher Apr 2019

A Fea/Cfd Study Of Heat Transfer To Semi-Trailer Disc Brake Wheel-End Components During A Braking Event, Justin P. Fisher

Masters Theses

Foundation air disc brakes bring Class 8 semi-trailers to a stop by converting kinetic energy into thermal energy. Recently, side skirts have been added to the underside of semi-trailers to improve fuel economy. The reduction in airflow under the trailer they create has potential to increase brake temperatures by reducing convection heat transfer. This will require an increase in conduction and radiation heat transfer to the surrounding wheel-end parts. Additional heat transfer to the surrounding parts could increase the temperatures in the hub and bearing to damaging levels.

CFD analyses were developed to model the airflow under the semi-trailer with ...


Algorithm For Geodetic Positioning Based On Angle-Of-Arrival Of Automatic Dependent Surveillance-Broadcasts, Richard Allen Gross Apr 2019

Algorithm For Geodetic Positioning Based On Angle-Of-Arrival Of Automatic Dependent Surveillance-Broadcasts, Richard Allen Gross

Masters Theses

This paper develops a non-precision, three-dimensional, geodetic positioning algorithm for airborne vehicles. The algorithm leverages the proliferation of Automatic Dependent Surveillance – Broadcast (ADS-B) equipped aircraft, utilizing them as airborne navigation aids to generate an RF Angle-of-Arrival (AOA) and Angle-of-Elevation (AOE) based geodetic position. The resulting geodetic position can serve as a redundant navigation system for use during locally limited Global Navigation Satellite System (GNSS) availability, be used to validate on-board satellite navigation systems in an effort to detect local spoofing attempts, and be used to validate ADS-B position reports.

The navigation algorithm is an implementation of an Extended Kalman Filter ...


To Study The Current Distributions Of An Antenna In Magnetized Collisional Plasma Via Pffdtd Simulations, Sindhuja Moravineni Apr 2019

To Study The Current Distributions Of An Antenna In Magnetized Collisional Plasma Via Pffdtd Simulations, Sindhuja Moravineni

Masters Theses

This thesis paper talks about the study of current distributions on dipole antenna immersed in collisional plasma. Analytical models like Balmain’s[6] one dimensional triangular current distribution, Staras[8] proposed and developed by Nikitin’s[10] threedimensional exponential current distribution and the PF-FDTD (Plasma Fluid- Finite Difference Time Domain) model[11] are compared against the Auroral Space Structure Probe (ASSP) flight data in order to show how data analysis can benefit. PF-FDTD model is used to study the antenna in weakly collisional plasma and the comparisons of the analytical and numerical solutions show that numerical model match better for ...


A Comparative Study Of Wireless Star Networks Implemented With Current Wireless Protocols, Sizen Neupane Feb 2019

A Comparative Study Of Wireless Star Networks Implemented With Current Wireless Protocols, Sizen Neupane

Masters Theses

Wireless communication is one of the most advanced technological developments of this era. Wireless technology enables both short-range and long-range services. Today, there are several different wireless communication technologies in existence. Each has its characteristics different from another one. This thesis will implement three short-range wireless technologies in star connection and compare the performance in the wireless network.

For this thesis, the performance of three different RF protocols - a proprietary packet protocol called Enhanced ShockBurst in nRF24L01+, Bluetooth Low Energy, and a special Wi- Fi protocol ESP-Now was compared. The general concept was to establish a star network for these ...


Distributed Element Designs For A Wireless System, Nicholas Anthony Dipisa Feb 2019

Distributed Element Designs For A Wireless System, Nicholas Anthony Dipisa

Masters Theses

A prototype binary frequency shift keying (BFSK) RF link operating in the 2.4 GHz ISM band was identified as a need for a potential undergraduate engineering laboratory activity. This system would be used to showcase various RF circuit engineering principles and techniques such as controlled trace impedances, frequency mixing, voltage-controlled oscillators, distributed element filters, and power splitters. This investigation focused on designing a prototype system that put a priority on ease of measurement and circuit tuning to help foster a more hands on approach. Each major circuit element was broken into separate PCBs to increase the modularity of the ...


Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet Jan 2019

Insar Simulations For Swot And Dual Frequency Processing For Topographic Measurements, Gerard Masalias Huguet

Masters Theses

In Earth remote sensing precise characterization of the backscatter coefficient is important to extract valuable information about the observed target. A system that eliminates platform motion during near-nadir airborne observations is presented in this thesis, showing an improvement on the accuracy of measurements for a Ka- band scatterometer previously developed at Microwave Remote Sensing Laboratory (MIRSL). These very same results are used to simulate the reflectivity of such targets as seen from a spaceborne radar and estimate height errors based on mission-specific geometry. Finally, data collected from a dual-frequency airborne interferometer com- prised by the Ka-band system and an S-band ...


The Evacuation Problem In Multi-Story Buildings, Quang Hong Cung Jan 2019

The Evacuation Problem In Multi-Story Buildings, Quang Hong Cung

Masters Theses

The pressure from high population density leads to the creation of high-rise structures within urban areas. Consequently, the design of facilities which confront the challenges of emergency evacuation from high-rise buildings become a complex concern. This paper proposes an embedded program which combines a deterministic (GMAFLAD) and stochastic model (M/G/C/C State Dependent Queueing model) into one program, GMAF_MGCC, to solve an evacuation problem. An evacuation problem belongs to Quadratic Assignment Problem (QAP) class which will be formulated as a Quadratic Set Packing model (QSP) including the random flow out of the building and the random pairwise traffic ...


Forecasting The Cost Of Electricity Generated By Offshore Wind Turbines, Timothy Costa Jan 2019

Forecasting The Cost Of Electricity Generated By Offshore Wind Turbines, Timothy Costa

Masters Theses

To impede the progress of climate change, many policy makers are considering avenues to decarbonize electricity production. In addition to decarbonization, policy makers must consider how the cost of electricity will impact various stakeholders, balancing cost and social benefits. Offshore wind farms have the potential to produce affordable, carbon-free electricity, but they are a relatively new technology. The relative juvenescence of offshore wind lends itself to an uncertain future, regarding production costs. In this thesis, we seek to understand cost drivers behind offshore wind electricity by analyzing historic trends in offshore wind levelized cost of electricity (LCOE) through learning curves ...


Improving Resilience Of Communication In Information Dissemination For Time-Critical Applications, Rajvardhan Somraj Deshmukh Jan 2019

Improving Resilience Of Communication In Information Dissemination For Time-Critical Applications, Rajvardhan Somraj Deshmukh

Masters Theses

Severe weather impacts life and in this dire condition, people rely on communication, to organize relief and stay in touch with their loved ones. In such situations, cellular network infrastructure\footnote{We refer to cellular network infrastructure as infrastructure for the entirety of this document} might be affected due to power outage, link failures, etc. This urges us to look at Ad-hoc mode of communication, to offload major traffic partially or fully from the infrastructure, depending on the status of it.

We look into threefold approach, ranging from the case where the infrastructure is completely unavailable, to where it has ...


A Computational Simulation Model For Predicting Infectious Disease Spread Using The Evolving Contact Network Algorithm, Buyannemekh Munkhbat Jan 2019

A Computational Simulation Model For Predicting Infectious Disease Spread Using The Evolving Contact Network Algorithm, Buyannemekh Munkhbat

Masters Theses

Commonly used simulation models for predicting outbreaks of re-emerging infectious diseases (EIDs) take an individual-level or a population-level approach to modeling contact dynamics. These approaches are a trade-off between the ability to incorporate individual-level dynamics and computational efficiency. Agent-based network models (ABNM) use an individual-level approach by simulating the entire population and its contact structure, which increases the ability of adding detailed individual-level characteristics. However, as this method is computationally expensive, ABNMs use scaled-down versions of the full population, which are unsuitable for low prevalence diseases as the number of infected cases would become negligible during scaling-down. Compartmental models use ...


Electrospinning Nanofibers From Chitosan-Hyaluronic Acid Complex Coacervates, Juanfeng Sun Jan 2019

Electrospinning Nanofibers From Chitosan-Hyaluronic Acid Complex Coacervates, Juanfeng Sun

Masters Theses

Electrospun nanofibers have been used for many applications, but a reliance on organic solvents limits their use in biomedical fields. In this study, we successfully electrospun nanofibers from aqueous chitosan-hyaluronic acid complex coacervates. We studied how solvent’ properties affected the average nanofiber diameter by using pure water as a solvent versus ethanol-water solutions. Experimentally, we investigated the effect of electrospinning apparatus parameters, such as how the applied voltage affected fiber formation and morphology. The smallest average nanofiber diameter was determined to be around 115 ± 30 nm when 3 wt% ethanol coacervate samples were electrospun using the applied voltage of 24 ...


Modeling The Effect Of New Commuter Bus Service On Demand And The Impact On Ghg Emissions: Application To Greater Boston, Christopher Lyman Jan 2019

Modeling The Effect Of New Commuter Bus Service On Demand And The Impact On Ghg Emissions: Application To Greater Boston, Christopher Lyman

Masters Theses

The transportation sector is considered one of the major contributors to greenhouse gas (GHG) emissions in metropolitan areas, and any efforts to reduce these emissions requires strategic management of multiple transportation modes. This paper presents a method to identify opportunities to reduce GHG emissions by expanding commuter bus services and incentives to shift commuters from private cars to transit. The approach uses a nested multinomial logit model for mode choice in a region that includes driving alone, carpooling, walking, cycling, and using four possible transit modes (ferry, commuter rail, rapid transit and bus) by walk access or driving access. A ...


The Umass Experimental X-Band Radar (Umaxx): An Upgrade Of The Casa Ma-1 To Support Cross-Polarization Measurements, Jezabel Vilardell Sanchez Jan 2019

The Umass Experimental X-Band Radar (Umaxx): An Upgrade Of The Casa Ma-1 To Support Cross-Polarization Measurements, Jezabel Vilardell Sanchez

Masters Theses

Ground-based radars are instruments commonly used to surveil the precipitation climate of the surrounding areas. Weather events are characterized by collecting backscatter data and analyzing computed products such as the Reflectivity Factor, the Doppler Velocity, the Spectrum Width, the Differential Reflectivity, the Co-polar Correlation Coefficient and the Differential Propagation Phase. The ability of the radar to transmit different polarization waves, such as horizontal and vertical polarization, allow for further analysis of the weather given the capability to perform co-polar and cross-polar measurements. The Linear Depolarization Ratio is another computed product based on the difference in power between the co-polarized and ...


Computational Fluid Dynamics Models Of Electromagnetic Levitation Experiments In Reduced Gravity, Gwendolyn Bracker Jan 2019

Computational Fluid Dynamics Models Of Electromagnetic Levitation Experiments In Reduced Gravity, Gwendolyn Bracker

Masters Theses

Electromagnetic levitation experiments provide a powerful tool that allows for the study of nucleation, solidification and growth in a containerless processing environment. Containerless processing allows for the study of reactive melts at elevated temperatures without chemical interactions or contamination from a container. Further, by removing the interface between the liquid and its container, this processing technique allows for greater access to the undercooled region for solidification studies. However, in these experiments it is important to understand the magnetohydrodynamic flow within the sample and the effects that this fluid flow has on the experiment.

A recent solidification study found that aluminum-nickel ...


On The Fuel Spray Applications Of Multi-Phase Eulerian Cfd Techniques, Gabriel Lev Jacobsohn Jan 2019

On The Fuel Spray Applications Of Multi-Phase Eulerian Cfd Techniques, Gabriel Lev Jacobsohn

Masters Theses

Eulerian-Eulerian Computational Fluid Dynamics (CFD) techniques continue to show promise for characterizing the internal flow and near-field spray for various fuel injection systems. These regions are difficult to observe experimentally, and simulations of such regions are limited by computational expense or reliance on empiricism using other methods. The physics governing spray atomization are first introduced. Impinging jet sprays and Gasoline Direct Injection (GDI) are selected as applications, and modern computational/experimental approaches to their study are reviewed. Two in-house CFD solvers are described and subsequently applied in several case studies. Accurate prediction of the liquid distribution in a like-doublet impinging ...


High Fidelity Modeling Of Cold-Formed Steel Single Lap Shear Screw Fastened Connections, Rita Kalo Jan 2019

High Fidelity Modeling Of Cold-Formed Steel Single Lap Shear Screw Fastened Connections, Rita Kalo

Masters Theses

Cold-formed steel connections are commonly fastened using self-tapping self-drilling screws. The behavior of these connections can differ based on the screw manufacturer or the cold-formed steel product used, both of which have a large selection available for use in industry. Because of their popularity and the many possible variations of these connections, researchers have frequently tested screw connections to characterize their behavior. However, repeatedly conducting this type of experiment is time consuming and expensive. Therefore, the purpose of this work was to create finite element models that can successfully predict the behavior of single lap shear screw connections, a common ...


Performance Of Concrete Tunnel Systems Subject To Fault Displacement, Michael Morano Jan 2019

Performance Of Concrete Tunnel Systems Subject To Fault Displacement, Michael Morano

Masters Theses

A Finite Element Analysis (FEA) investigation of concrete tunnel systems traversing seismic faults is carried out to determine how to effectively mitigate the stresses induced in the liner when subject to fault displacement. A parametric study of various fault parameters, both in the damage zone and competent rock, is carried out to determine the site conditions which induce the most stress on the tunnel liner system. Results indicate that friction angle, cohesion, and elastic modulus of fault zones have varying effects on the stresses induced on the liner. The width of damage zone and expected displacements are also investigated and ...


Ammonia Production From A Non-Grid Connected Floating Offshore Wind-Farm: A System-Level Techno-Economic Review, Vismay V. Parmar Jan 2019

Ammonia Production From A Non-Grid Connected Floating Offshore Wind-Farm: A System-Level Techno-Economic Review, Vismay V. Parmar

Masters Theses

According to U.S. Department of Energy, offshore wind energy has the potential to generate 7,200 TWh of energy annually, which is nearly twice the current annual energy consumption in the United States. With technical advances in the offshore wind industry, particularly in the floating platforms, windfarms are pushing further into the ocean. This creates new engineering challenges for transmission of energy from offshore site to onshore. One possible solution is to convert the energy produced into chemical energy of ammonia, which was investigated by Dr. Eric Morgan. In his doctoral dissertation, he assessed the technical requirements and economics ...


Sustainable Travel Incentives Optimization In Multimodal Networks, Hossein Ghafourian Jan 2019

Sustainable Travel Incentives Optimization In Multimodal Networks, Hossein Ghafourian

Masters Theses

Tripod, an integrated bi-level transportation management system, is a smartphone application from the potential user’s point of view which would be instantly accessed prior to performing the trip. Since there are constantly several alternatives for any trip, Tripod considers a series and combination of various parameters, including departure time, mode and route, and rewards for each alternative with a number of redeemable points for goods and services called “Tokens”. The framework responsible for computing the optimized number of tokens awarded to the set of available alternatives in order to minimize the system-wide energy consumption under a constrained Token budget ...


Advanced Virtual Reality Headset Based Training To Improve Young Drivers’ Latent Hazard Anticipation Ability, Ravi Agrawal Jan 2019

Advanced Virtual Reality Headset Based Training To Improve Young Drivers’ Latent Hazard Anticipation Ability, Ravi Agrawal

Masters Theses

Driving safety among young novice driver is one of the largest concern in the transportation domain. Many Paper-based or PC- based training program have been developed over the years to train the young novice driver to improve their driving skills (Hazard Anticipation). This training programs does help young novice driver to improve their situational awareness and so the hazard anticipation skills. But, there is one common problem with most of the currently available training programs. They are not very immersive, because such training program mostly provide plain view of the training scenario’s along with some description about the scenario ...


A Study On Controlling Power Supply Ramp-Up Time In Sram Pufs, Harshavardhan Ramanna Jan 2019

A Study On Controlling Power Supply Ramp-Up Time In Sram Pufs, Harshavardhan Ramanna

Masters Theses

With growing connectivity in the modern era, the risk of encrypted data stored in hardware being exposed to third-party adversaries is higher than ever. The security of encrypted data depends on the secrecy of the stored key. Conventional methods of storing keys in Non-Volatile Memory have been shown to be susceptible to physical attacks. Physically Unclonable Functions provide a unique alternative to conventional key storage. SRAM PUFs utilize inherent process variation caused during manufacturing to derive secret keys from the power-up values of SRAM memory cells.

This thesis analyzes the effect of supply ramp-up times on the reliability of SRAM ...


Calculation Of Scalar Isosurface Area And Applications, Kedar Prashant Shete Jan 2019

Calculation Of Scalar Isosurface Area And Applications, Kedar Prashant Shete

Masters Theses

The problem of calculating iso-surface statistics in turbulent flows is interesting for a number of reasons, some of them being combustion modeling, entrainment through turbulent/non-turbulent interfaces, calculating mass flux through iso-scalar surfaces and mapping of scalar fields. A fundamental effect of fuid turbulence is to wrinkle scalar iso-surfaces. A review of the literature shows that iso-surface calculations have primarily been done with geometric methods, which have challenges when used to calculate surfaces that have high complexity, such as in turbulent flows. In this thesis, we propose an alternative integral method and test it against analytical solutions. We present a ...


The Promise Of Vr Headsets: Validation Of A Virtual Reality Headset-Based Driving Simulator For Measuring Drivers’ Hazard Anticipation Performance, Ganesh Pai Mangalore Jan 2019

The Promise Of Vr Headsets: Validation Of A Virtual Reality Headset-Based Driving Simulator For Measuring Drivers’ Hazard Anticipation Performance, Ganesh Pai Mangalore

Masters Theses

The objective of the current study is to evaluate the use of virtual reality (VR) headsets to measure driving performance. This is desirable because they are several orders of magnitude less expensive and, if validated, could greatly extend the powers of simulation. Out of several possible measures of performance that could be considered for evaluating VR headsets, the current study specifically examines drivers’ latent hazard anticipation behavior both because it has been linked to crashes and because it has been shown to be significantly poorer in young drivers compared to their experienced counterparts in traditional driving simulators and in open ...


Behavior Of Prestressed Concrete Bridges With Closure Pour Connections And Diaphragms, Gercelino Ramos Jan 2019

Behavior Of Prestressed Concrete Bridges With Closure Pour Connections And Diaphragms, Gercelino Ramos

Masters Theses

Accelerated Bridge Construction (ABC) has gained substantial popularity in new bridge construction and bridge deck replacement because it offers innovative construction techniques that result in time and cost savings when compared to traditional bridge construction practice. One technology commonly implemented in ABC to effectively execute its projects is the use of prefabricated bridge components (precast/prestressed bridge components). Precast/prestressed bridge components are fabricated offsite or near the site and then connected on-site using small volume closure pour connections. Diaphragms are also commonly used to strengthen the connection between certain prefabricated components used in ABC, such as beam elements. Bridges ...


Analysis Of Construction Fall Protection Guardrails In A Population With Changing Anthropometrics, Connor S. Klinzing Jan 2019

Analysis Of Construction Fall Protection Guardrails In A Population With Changing Anthropometrics, Connor S. Klinzing

Masters Theses

The construction trade has commonly been cited as one of the most dangerous industries within the United States, with falls from elevation being the most predominate cause for injuries and deaths. The OSHA standards related guardrails has not changed since its implementation in 1970. These standards originally derive from the 1950s, which expect a 160-pound person with 40 pounds of equipment, tools, etc. However, the anthropometries of the common working age citizen has dramatically changed in respects to their weight. This study examines the relationship of the guardrail system to the changing anthropometries to determine if a reform is necessary ...


Vhf Transmitter Development For Wildlife Tracking, Bryan Westra Jan 2019

Vhf Transmitter Development For Wildlife Tracking, Bryan Westra

Masters Theses

Wildlife biologists often use collars with VHF transmitters to gather wildlife data. The purpose of this project is to determine the best approach to designing a wildlife tracking VHF transmitter on a Printed Circuit Board (PCB). A variety of frequency generation methods were considered for the transmitter, including transistor-based crystal oscillators and chip based solutions from the chip manufacturers Analog Devices and Silicon Labs. Prototypes of the feasible options were built and evaluated for cost, power consumption, efficiency, size, frequency range, signal bandwidth, and frequency stability. It was found that the Silicon Labs Si4010 chip was the best solution based ...


Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer Jan 2019

Removal Of Antimony And Bismuth From Copper Electrorefining Electrolyte By Two Proprietary Solvent Extraction Extractants, Andrew Artzer

Masters Theses

"Antimony and bismuth are two of the most problematic impurities in copper electrorefining (ER). Because of this, much research has been done investigating the ways to remove them. Processes that are currently being used industrially include anode additions, liberators, ion exchange (IX), and solvent extraction (SX). Of these, liberators and anode additions are the most common while SX is the least, mostly being used for arsenic removal. There are other methods that have been evaluated, but are not in commercial use. These include the use of various electrolyte additives, and adsorbents such as bentonite clay and heavy metal sulfates.

Two ...


Unified Probe Launch Pattern Design And Methodology Of Differential Probe Characterization, Han Deng Jan 2019

Unified Probe Launch Pattern Design And Methodology Of Differential Probe Characterization, Han Deng

Masters Theses

"Differential probe is wildly used in the signal integrity area to do the accuracy signal measurement in frequency domain or time domain. Comparing with traditional SMA connector measurement, the probe measurement has several advantages such as the high flexibility and measurement efficiency. Nevertheless, the probe has some disadvantages such as multiple design patterns and the difficulty of fast landing. In this thesis, a unified probe landing pattern is provided to solve the con of probes and a probe testing fixture is designed for characterize probe and extract the probe model.

In the first portion, a unified differential probe launching pattern ...