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Masters Theses

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Full-Text Articles in Engineering

Correcting For Terrain Interference, Attenuation, And System Bias For A Dual Polarimetric, X-Band Radar, Casey Wolsieffer Apr 2021

Correcting For Terrain Interference, Attenuation, And System Bias For A Dual Polarimetric, X-Band Radar, Casey Wolsieffer

Masters Theses

This thesis outlines the procedure and theory used to calibrate the UMass eXperimental X-band Radar (UMAXX) for the purpose of monitoring meteorological events in the Pioneer Valley region. Due to the complex topography of the area, lower tilt angles are subject to partial or full beam blockage as well as ground clutter observed through the main beam or sidelobes. Additionally, there are biases internal and external to the system that impact the reflectivity and differential reflectivity measurements. These biases and corrections are addressed in this work. As the radar has been operational since September of 2018, there is ample data ...


Ground Source Heat Pumps: Considerations For Large Facilities In Massachusetts, Eric Wagner Apr 2021

Ground Source Heat Pumps: Considerations For Large Facilities In Massachusetts, Eric Wagner

Masters Theses

There has been a significant increase in the interest and implementations of heat pump systems for HVAC purposes in general and of ground source heat pumps (GSHPs) in particular. Though these systems have existed for decades, primarily in Europe, there has been an upward trend particularly in the United States in recent years. With the world-wide push toward CO2 emissions reduction targets, interest in heat pump systems to reduce CO2 emissions from heating and cooling is likely to only increase in the future. However, more than ever, financial considerations are also key factors in the implementation of any ...


Mechanical Design And Analysis: High-Precision Microcontact Printhead For Roll-To-Roll Printing Of Flexible Electronics, Mehdi Riza Apr 2021

Mechanical Design And Analysis: High-Precision Microcontact Printhead For Roll-To-Roll Printing Of Flexible Electronics, Mehdi Riza

Masters Theses

Flexible electronics have demonstrated potential in a wide range of applications including wearable sensors, photovoltaics, medical devices and more, due to their properties of extreme adaptability while also being lightweight and highly robust. The main challenge standing in the way of progress in this field is the difficulty of large-scale manufacturing of these flexible electronics compared to their rigid counterparts. Microcontact printing is a form of soft lithography in which an elastomeric stamp is used to transfer sub-micron scale surface patterns onto a flexible substrate via ink monolayers. The integration of microcontact printing into a roll-to-roll (R2R) system will enable ...


Utilizing Unmanned Aerial Vehicles (Uavs) For The Estimation Of Beam Corrosion Of Steel Bridge Girders, Gabrielle Pryor Apr 2021

Utilizing Unmanned Aerial Vehicles (Uavs) For The Estimation Of Beam Corrosion Of Steel Bridge Girders, Gabrielle Pryor

Masters Theses

The transportation infrastructure in the United States is a complex system that is vital to the everyday operations of the country. Bridges are a significant asset of this network, with many of them approaching the end of their service life. Corrosion is a common cause of deterioration which ultimately results to structural deficiency for the aging bridges. The deterioration rate is a multi-aspect factor that makes bridge inspections crucial. However, the current bridge inspections are very costly and potentially unsafe for the involved personnel. To lower costs and increase safety, many state DOT’s and universities have decided to perform ...


Fabrication Of Binder-Free Electrodes Based On Graphene Oxide With Cnt For Decrease Of Resistance, Di Zhang Dec 2020

Fabrication Of Binder-Free Electrodes Based On Graphene Oxide With Cnt For Decrease Of Resistance, Di Zhang

Masters Theses

In electrode double layer capacitor (EDLC), electrodes usually contain binder materials to provide adhesion between electrode materials. However, binder materials usually bring unwanted resistances to the component due to their non-conductivity properties and the occupation of ion cavities. The purpose of this thesis is to demonstrate the feasibility of fabricating electrodes for EDLCs by using carbon nanotubes (CNTs) and graphene oxide (GO) without using any binding materials. At the same time, investigating the binder-free electrode’s electrochemical properties and make an assumption of its potential application in the future.

The slurry of binder-free electrodes was fabricated by ultrasonicating water suspended ...


Real-Time Tddft-Based Filtered Spectroscopy, Ivan Williams Dec 2020

Real-Time Tddft-Based Filtered Spectroscopy, Ivan Williams

Masters Theses

We demonstrate the ability to simulate targeted excitation of atomistic systems using our real-time TDDFT-based simulation framework NESSIE. Traditional ap- proaches for extracting spectra through real-time TDDFT involves excitation of all frequencies via impulse requiring long simulation times and yielding poor resolution. By exciting the system with a modulated sinc pulse between the frequencies of inter- est we are able to obtain a spectral response with far more precision in a significantly shorter time frame than competing implementations.


Optimal Mammography Schedule Estimates Under Varying Disease Burden, Infrastructure Availability, And Other Cause Mortality: A Comparative Analyses Of Six Low- And Middle- Income Countries, Shifali Shifali Dec 2020

Optimal Mammography Schedule Estimates Under Varying Disease Burden, Infrastructure Availability, And Other Cause Mortality: A Comparative Analyses Of Six Low- And Middle- Income Countries, Shifali Shifali

Masters Theses

Low-and-middle-income countries (LMICs) have a higher mortality-to-incidence ratio for breast cancer compared to high-income countries (HICs) because of late-stage diagnosis. Mammography screening is recommended for early diagnosis, however, current screening guidelines are only generalized by economic disparities, and are based on extrapolation of data from randomized controlled trials in HICs, which have different disease burdens and all-cause mortality compared to LMICs. Moreover, the infrastructure capacity in LMICs is far below that needed for adopting current screening guidelines. This study analyzes the impact of disease burden, infrastructure availability, and other cause mortality on optimal mammography screening schedules for LMICs. Further, these ...


Network Virtualization And Emulation Using Docker, Openvswitch And Mininet-Based Link Emulation, Narendra Prabhu Dec 2020

Network Virtualization And Emulation Using Docker, Openvswitch And Mininet-Based Link Emulation, Narendra Prabhu

Masters Theses

With the advent of virtualization and artificial intelligence, research on networked systems has progressed substantially. As the technology progresses, we expect a boom in not only the systems research but also in the network of systems domain. It is paramount that we understand and develop methodologies to connect and communicate among the plethora of devices and systems that exist today. One such area is mobile ad-hoc and space communication, which further complicates the task of networking due to myriad of environmental and physical conditions. Developing and testing such systems is an important step considering the large investment required to build ...


Metric Learning Via Linear Embeddings For Human Motion Recognition, Byoungdoo Kong Dec 2020

Metric Learning Via Linear Embeddings For Human Motion Recognition, Byoungdoo Kong

Masters Theses

We consider the application of Few-Shot Learning (FSL) and dimensionality reduction to the problem of human motion recognition (HMR). The structure of human motion has unique characteristics such as its dynamic and high-dimensional nature. Recent research on human motion recognition uses deep neural networks with multiple layers. Most importantly, large datasets will need to be collected to use such networks to analyze human motion. This process is both time-consuming and expensive since a large motion capture database must be collected and labeled. Despite significant progress having been made in human motion recognition, state-of-the-art algorithms still misclassify actions because of characteristics ...


Nozzle Clogging Prevention And Analysis In Cold Spray, Alden Foelsche Dec 2020

Nozzle Clogging Prevention And Analysis In Cold Spray, Alden Foelsche

Masters Theses

Cold spray is an additive manufacturing method in which powder particles are accelerated through a supersonic nozzle and impinged upon a nearby substrate, provided they reach their so-called critical velocity. True to its name, the cold spray process employs lower particle temperatures than other thermal spray processes while the particle velocities are comparably high. Because bonding occurs mostly in the solid state and at high speeds, cold spray deposits are distinguished for having low porosity and low residual stresses which nearly match those of the bulk material.

One complication with the cold spray process is the tendency for nozzles to ...


A Study On Latent Thermal Energy Storage (Ltes) Using Phase Change Materials (Pcms) 2020, Ritvij Dixit Dec 2020

A Study On Latent Thermal Energy Storage (Ltes) Using Phase Change Materials (Pcms) 2020, Ritvij Dixit

Masters Theses

The significant increase in energy requirements across the world, provides several opportunities for innovative methods to be developed to facilitate the storage and utilization of energy. The major energy demand is in the form of electrical energy for domestic as well as industrial sectors, a large part of which are the heating and cooling requirements. Appropriate utilization of thermal energy storage can effectively aid in reducing the electrical demand by storage and release of this thermal energy during peak hours.

Thermal Energy Storage using Phase Change Materials (PCMs) is an attractive method of energy storage, with a wide variety of ...


An Investigation Into The Development Of A Low Cost, Easy To Use Seizure Analysis Tool., Cody Dean Dec 2020

An Investigation Into The Development Of A Low Cost, Easy To Use Seizure Analysis Tool., Cody Dean

Masters Theses

The need for collaborating and sharing data and research between doctors, researchers, universities and patients has never been more necessary. We are seeing firsthand how a deadly virus can completely devastate the world in a matter of months and being able to react quickly is the top priority. Open source tools are making it possible to share research and learnings about viruses like COVID-19 across countries, industries, and universities and these tools and philosophies extend across all areas of medical research.

The amount of data that is being collected within the medical industry is increasing at an exponential rate and ...


Modeling The Torque Of Ferrite Nano-Particles As A Ferrofluid Suspended In Liquid To Determine The Electromagnetic Response To Angular Displacement, Jackson Tyler Brennecke Dec 2020

Modeling The Torque Of Ferrite Nano-Particles As A Ferrofluid Suspended In Liquid To Determine The Electromagnetic Response To Angular Displacement, Jackson Tyler Brennecke

Masters Theses

Inertial sensing is an important part of engineering and technology, especially for determining spatial orientation. Most modern inertial sensing units rely on MicroElectroMechanical systems (MEMS) style gyroscopic sensors to determine angular acceleration. This research investigates a novel gyroscopic sensing technology that uses mechanical precision of magnetic nanoparticles, instead of MEMS, to determine inertial measurements. The only other study on this novel technology proposed a scalar set of equations for relating magnetic field and torque magnitude to the magnitude of angular displacement of the sensor. This research develops the theoretical model into a set of full vector equations, so that the ...


A Cfd Study Of Operation Room Air Conditioning: Air Curtain Performance, Spencer Lee Boer Dec 2020

A Cfd Study Of Operation Room Air Conditioning: Air Curtain Performance, Spencer Lee Boer

Masters Theses

An operation room is a critical environment when it comes to the safety of patients undergoing surgery. There are a lot of factors that go into reducing Surgical Site Infections (SSI) following a surgery. This comes in the form of cleaning standards, surgical practices, but also environment controls. The characteristics of airflow within an operation room are related to the risk of an SSI. Some of these factors are temperature, velocity, and turbulent air around an open wound which could increase the chance of bacteria or other particles entering the very vulnerable patient. As clean room standards continue to be ...


Development Of A Tiny House Design Tool To Increase Safety, Efficiency, And Cost-Effectiveness, Michael Joseph Stratton Ii Dec 2020

Development Of A Tiny House Design Tool To Increase Safety, Efficiency, And Cost-Effectiveness, Michael Joseph Stratton Ii

Masters Theses

A growing number of people are choosing to live more sustainably, and this is commonly done through living in an extremely small house, also called a “tiny house”. There is no set definition for a tiny house, but it typically refers to a structure less than 500 ft2, sometimes built by the homeowner, and frequently built on a travel trailer.

The popularity of tiny houses has increased over the years due to different television shows, internet videos, and photo sharing websites, but the technical details are rarely covered, which is why this study examines the structural, stability, weight, and thermal ...


Optimization Of Thermal Energy Storage Sizing Using Thermodynamic Analysis, Andrew Villanueva Aug 2020

Optimization Of Thermal Energy Storage Sizing Using Thermodynamic Analysis, Andrew Villanueva

Masters Theses

The aim of this thesis is to examine the effect that Thermal Energy Storage (TES) sizing has on a building’s ability to meet heating and cooling demands in an energy and cost efficient manner. The focus of the research is the quantification the effects of TES for system sizing and boiler cycling. Research is accomplished by modelling TES systems with various storage capacities using thermodynamic analysis. Energy costs are subject to increase during peak usage periods due to a limited supply of energy. Peak heating and cooling periods also force thermal systems to be sized for loads that are ...


Thermal Transport Modeling Of Semiconductor Materials From First Principles, Aliya Qureshi Aug 2020

Thermal Transport Modeling Of Semiconductor Materials From First Principles, Aliya Qureshi

Masters Theses

Over the past few years, the size of semiconductor devices has been shrinking whereas the density of transistors has exponentially increased. Thus, thermal management has become a serious concern as device performance and reliability is greatly affected by heat. An understanding of thermal transport properties at device level along with predictive modelling can lead us to design of new systems and materials tailored according to the thermal conductivity. In our work we first review different models used to calculate thermal conductivity and examine their accuracy using the experimentally measured thermal conductivity for Si. Our results suggest that empirically calculated rates ...


Changes In Neural Network Connectivity Of Normal Young Adults In Response To Power Wheelchair Trainer Using Eeg Coherence, Ruby Phung Aug 2020

Changes In Neural Network Connectivity Of Normal Young Adults In Response To Power Wheelchair Trainer Using Eeg Coherence, Ruby Phung

Masters Theses

The ability to move and explore their surrounding environment plays a critical role in the development of cognitive function in children, especially during early childhood. The lack of independent and autonomous mobility is, therefore, a clear disadvantage for the overall development of children with multiple, severe disabilities. Limited number of studies have been conducted on the impact of power mobility device on this specific population. Previous exploratory and pilot studies showed promising results regarding quantifiable and consistent changes in the electroencephalogram (EEG) of children with multiple, severe disabilities when provided with power mobility training. This study aimed to further extend ...


Numerical Simulation Of Thermoelectric Transport In Bulk And Nanostructured Sisn Alloys, Venkatakrishna Dusetty Jul 2020

Numerical Simulation Of Thermoelectric Transport In Bulk And Nanostructured Sisn Alloys, Venkatakrishna Dusetty

Masters Theses

The current high demand for sustainable and renewable energy sources to solve world energy crisis has enormously increased interest in looking at alternative sources of energy. All the machines used in manufacturing process, electricity generation, residential applications, transportation etc., rejects energy in the form of heat into environment. Thermoelectric materials can convert thermal-to-electrical and electrical-to-thermal energy and can be utilized in waste-heat harvesting, more efficient cooling to reduce energy usage and CO2 emissions. Significant research efforts have been devoted over the past decade to thermoelectric materials, with particular emphasis being placed on combining materials selection with nanostructuring. The overarching ...


Compound Effects Of Clock And Voltage Based Power Side-Channel Countermeasures, Jacqueline Lagasse Jul 2020

Compound Effects Of Clock And Voltage Based Power Side-Channel Countermeasures, Jacqueline Lagasse

Masters Theses

The power side-channel attack, which allows an attacker to derive secret information from power traces, continues to be a major vulnerability in many critical systems. Numerous countermeasures have been proposed since its discovery as a serious vulnerability, including both hardware and software implementations. Each countermeasure has its own drawback, with some of the highly effective countermeasures incurring large overhead in area and power. In addition, many countermeasures are quite invasive to the design process, requiring modification of the design and therefore additional validation and testing to ensure its accuracy. Less invasive countermeasures that do not require directly modifying the system ...


School Bus Routing To Allow Later School Start Times, Rana Eslamifard Jul 2020

School Bus Routing To Allow Later School Start Times, Rana Eslamifard

Masters Theses

School districts providing busing services for students who live too far to walk to school. In many districts a fleet of school buses is used in sequence to transport high school students, then middle school students, and then elementary school students. The result is that high school classes must start much earlier in the morning than the elementary school, and buses may traverse similar routes three times each morning and afternoon. In light of recent research on the benefits of later high school start times and the need to control transportation costs, school districts are seeking efficient school bus routing ...


Modeling Of Electrical Grid Systems To Evaluate Sustainable Electricity Generation In Pakistan, Muhammad Mustafa Amjad Jul 2020

Modeling Of Electrical Grid Systems To Evaluate Sustainable Electricity Generation In Pakistan, Muhammad Mustafa Amjad

Masters Theses

Pakistan has always had a history of severe energy shortfalls, which rose up to an alarming 33% in 2013. This situation was countered by investments in the energy sector through the China Pakistan Economic Corridor (CPEC), which were unfortunately largely based on brown fuels. Although beneficial in the short term, these investments do not bode well for the climate scenario of Pakistan, with various parts of the country already having experienced temperatures rise of 1-3°C. To ensure that the current situation doesn’t exacerbate and is tackled in a timely manner, this research aims to examine how the untapped ...


Sundown: Model-Driven Per-Panel Solar Anomaly Detection For Residential Arrays, Menghong Feng Jul 2020

Sundown: Model-Driven Per-Panel Solar Anomaly Detection For Residential Arrays, Menghong Feng

Masters Theses

There has been significant growth in both utility-scale and residential-scale solar installa- tions in recent years, driven by rapid technology improvements and falling prices. Unlike utility-scale solar farms that are professionally managed and maintained, smaller residential- scale installations often lack sensing and instrumentation for performance monitoring and fault detection. As a result, faults may go undetected for long periods of time, resulting in generation and revenue losses for the homeowner. In this thesis, we present SunDown, a sensorless approach designed to detect per-panel faults in residential solar arrays. SunDown does not require any new sensors for its fault detection and ...


Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek May 2020

Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek

Masters Theses

As the number of electric vehicles (EVs) increases, the number of used battery packs that require disposal increases; however, many of these packs still have useful capacity and can be repurposed. When using repurposed large lithium-ion battery packs, deviations between cells within a pack become problematic. These deviations result in a pack that is unbalanced, affecting performance and proving potentially hazardous when charging. Consequently, a battery management system (BMS) is needed. To provide safety, the BMS in this paper monitors and controls the operation of the battery pack. In addition, it controls the redistribution of charge between the cells within ...


Accelerating Rsa Public Key Cryptography Via Hardware Acceleration, Pavithra Ramesh Apr 2020

Accelerating Rsa Public Key Cryptography Via Hardware Acceleration, Pavithra Ramesh

Masters Theses

A large number and a variety of sensors and actuators, also known as edge devices of the Internet of Things, belonging to various industries - health care monitoring, home automation, industrial automation, have become prevalent in today's world. These edge devices need to communicate data collected to the central system occasionally and often in burst mode which is then used for monitoring and control purposes. To ensure secure connections, Asymmetric or Public Key Cryptography (PKC) schemes are used in combination with Symmetric Cryptography schemes. RSA (Rivest - Shamir- Adleman) is one of the most prevalent public key cryptosystems, and has computationally ...


Crosstalk Based Side Channel Attacks In Fpgas, Chethan Ramesh Apr 2020

Crosstalk Based Side Channel Attacks In Fpgas, Chethan Ramesh

Masters Theses

As FPGA use becomes more diverse, the shared use of these devices becomes a security concern. Multi-tenant FPGAs that contain circuits from multiple independent sources or users will soon be prevalent in cloud and embedded computing environments. The recent discovery of a new attack vector using neighboring long wires in Xilinx SRAM FPGAs presents the possibility of covert information leakage from an unsuspecting user's circuit. The work makes two contributions that extend this finding. First, we rigorously evaluate several Intel SRAM FPGAs and confirm that long wire information leakage is also prevalent in these devices. Second, we present the ...


Quantification Of Thermal Bridging Effects In Cold-Formed Steel Wall Assemblies, Divyansh Kapoor Apr 2020

Quantification Of Thermal Bridging Effects In Cold-Formed Steel Wall Assemblies, Divyansh Kapoor

Masters Theses

Thermal bridging can be defined as the phenomenon where a structural element spanning the building envelope acts like a thermal pathway which collects and moves energy (heat) from the interior to the exterior of the structure. CFS construction, due to the high thermal conductivity of steel with respect to its surrounding structural components and repetitive nature of framing, is highly prone to thermal bridging. Thermal bridging significantly alters the thermal performance of wall assemblies.

Hence, the objective of this research project was to quantify the magnitude of energy loss through cold-formed steel (CFS) stud wall assemblies at a component level ...


Compressive Parameter Estimation Via Approximate Message Passing, Shermin Hamzehei Apr 2020

Compressive Parameter Estimation Via Approximate Message Passing, Shermin Hamzehei

Masters Theses

The literature on compressive parameter estimation has been mostly focused on the use of sparsity dictionaries that encode a discretized sampling of the parameter space; these dictionaries, however, suffer from coherence issues that must be controlled for successful estimation. To bypass such issues with discretization, we propose the use of statistical parameter estimation methods within the Approximate Message Passing (AMP) algorithm for signal recovery. Our method leverages the recently proposed use of custom denoisers in place of the usual thresholding steps (which act as denoisers for sparse signals) in AMP. We introduce the design of analog denoisers that are based ...


Investigation Of Selective Laser Melting Fabricated Internal Cooling Channels, Colin Jack Apr 2020

Investigation Of Selective Laser Melting Fabricated Internal Cooling Channels, Colin Jack

Masters Theses

Channels where coolant is run to cool a system are common in injection mold tooling. Conventionally, these channels are machined into the mold. This has limited the design of mold cooling systems to the constraints of traditional machining processes, where straight circular channels machined from cast material are typical. The transfer of heat away from the part cavity into these cooling channels has a large effect on the cooling time of the injection mold cycle. In this investigation, laser powder bed fusion processes were used to create non-circular cooling channels. To compare cooling performance, elliptical and circular channels of equal ...


Numerical Investigation Of Leading-Edge Modifications Of A Naca Airfoil, Anisur Rahman Ikram Apr 2020

Numerical Investigation Of Leading-Edge Modifications Of A Naca Airfoil, Anisur Rahman Ikram

Masters Theses

A parametric investigation was carried out to understand the flow characteristics of tubercle airfoils and to determine the best approach and parameters for designing a tubercle airfoil. For this purpose, a straight edge base airfoil (NACA 4414) and several tubercle airfoils, by modifying the leading edge of the base airfoil, were created in SolidWorks and tested with Computational Fluid Dynamics (CFD) application software Star CCM+.

Alternative tubercle airfoil with elliptical bumps demonstrated superior post-stall performance when compared to their straight edge counterparts; their post-stall lift did not decrease drastically. However, their pre-stall lift coefficients were always lower than the base ...