Engineering Commons^™

Reconstruction Of The 3d Temperature And Species Concentration Spatial Distribution Of A Jet Engine Exhaust Plume Using An Infrared Fourier Transform Spectrometer Hyperspectral Imager, Mason D. Paulec

Theses and Dissertations

The measurement of combustion byproducts is useful for determining pollution of any fuel burning application, efficiency of combustion, and determining detectability of aircraft exhausts. Both intrusive and non-intrusive techniques have been utilized to measure these quantities. For the majority of the non-intrusive techniques, the absorption and emission spectra of the gases are utilized for measurements. For this research, the use of the Telops Infrared Fourier Transform Spectrometer (IFTS) Hyperspectral Imager (HSI) was explored within the scope of combustion diagnostic methods, as an option for remote measurements of a jet turbine to determine concentration of species and temperature of the combustion …

The Military Inventory Routing Problem: Utilizing Heuristics Within A Least Squares Temporal Differences Algorithm To Solve A Multiclass Stochastic Inventory Routing Problem With Vehicle Loss, Ethan L. Salgado

Theses and Dissertations

Military commanders currently resupply forward operating bases (FOBs) from a central location within an area of operations mainly via convoy operations in a way that closely resembles vendor managed inventory practices. Commanders must decide when and how much inventory to distribute throughout their area of operations while minimizing soldier risk. Technology currently exists that makes utilizing unmanned cargo aerial vehicles (CUAVs) for resupply an attractive alternative due to the dangers of utilizing convoy operations. Enemy actions in wartime environments pose a significant risk to a CUAV's ability to safely deliver supplies to a FOB. We develop a Markov decision process …

Simplex Control Methods For Robust Convergence Of Small Unmanned Aircraft Flight Trajectories In The Constrained Urban Environment, Michael D. Zollars

Theses and Dissertations

Constrained optimal control problems for Small Unmanned Aircraft Systems (SUAS) have long suffered from excessive computation times caused by a combination of constraint modeling techniques, the quality of the initial path solution provided to the optimal control solver, and improperly defining the bounds on system state variables, ultimately preventing implementation into real-time, on-board systems. In this research, a new hybrid approach is examined for real-time path planning of SUAS. During autonomous flight, a SUAS is tasked to traverse from one target region to a second target region while avoiding hard constraints consisting of building structures of an urban environment. Feasible …

Methods To Support The Project Selection Problem With Non-Linear Portfolio Objectives, Time Sensitive Objectives, Time Sensitive Resource Constraints, And Modeling Inadequacies, Neil C. Ranly

Theses and Dissertations

The United States Air Force relies upon information production activities to gain insight regarding uncertainties affecting important system configuration and in-mission task execution decisions. Constrained resources that prevent the fulfillment of every information production request, multiple information requestors holding different temporal-sensitive objectives, non-constant marginal value preferences, and information-product aging factors that affect the value-of-information complicate the management of these activities. This dissertation reviews project selection research related to these issues and presents novel methods to address these complications. Quantitative experimentation results demonstrate these methods’ significance.

Optimal Finite Thrust Guidance Methods For Constrained Satellite Proximity Operations Inspection Maneuvers, Eric R. Prince

Theses and Dissertations

Algorithms are developed to find optimal guidance for an inspector satellite operating nearby a resident space object (RSO). For a non-maneuvering RSO, methods are first developed for a satellite subject to maximum slew rates to conduct an initial inspection of an RSO, where the control variables include the throttle level and direction of the thrust. Second, methods are developed to optimally maneuver a satellite with on/off thrusters into a natural motion circumnavigation or teardrop trajectory, subject to lighting and collision constraints. It is shown that for on/off thrusters, a control sequence can be parameterized to a relatively small amount of …

Satellite Articulation Sensing Using Computer Vision, David H. Curtis

Theses and Dissertations

Autonomous on-orbit satellite servicing benefits from an inspector satellite that can gain as much information as possible about the primary satellite. This includes performance of articulated objects such as solar arrays, antennas, and sensors. A method for building an articulated model from monocular imagery using tracked feature points and the known relative inspection route is developed. Two methods are also developed for tracking the articulation of a satellite in real-time given an articulated model using both tracked feature points and image silhouettes. Performance is evaluated for multiple inspection routes and the effect of inspection route noise is assessed. Additionally, a …

Development Of Domain Analysis For Determining Potential Pavement Damage, Angeli Gamez, Jaime Hernandez, Hasan Ozer, Imad L. Al-Qadi

Civil and Environmental Engineering Faculty Research and Publications

A new approach for quantifying flexible pavement damage potential is proposed. The new method, domain analysis, utilizes multiaxial results from advanced finite element models to calculate the response of flexible pavements to tire loading. The output is a single scalar value, which is unique to a given pavement structure and loading configuration. The ability of the domain analysis to quantify bulk damage potential and overcome flaws of conventional approaches based on point responses is demonstrated by testing three case studies: (1) comparison of typical loading conditions of dual-tire assembly (DTA), new-generation wide-base tire (NG-WBT), and steer tire; (2) effect of …

Improvement Of Fatal Crash Analysis And Follow-Up, William Nicholas Staats, Jerry G. Pigman, Kenneth R. Agent, Paul A. Ross

Kentucky Transportation Center Research Report

Executive Summary

Fatalities resulting from traffic crashes in Kentucky increased from a low of 638 in 2013 to 834 in 2016 (a 31% increase), and there is not a full understanding of the underlying causes for this trend. This study analyzes fatal crashes using data from both Kentucky’s crash reports and the National Highway Traffic Safety Administration’s (NHTSA) Fatal Accident Reporting System (FARS) to identify countermeasures to combat increasing fatal crash rates. In addition, this study compares Kentucky’s crash reports to the fatal crash data in FARS to identify data inconsistencies and recommend procedures to eliminate these inconsistencies.

Emphasis was …

Higher-Level Consistencies: Where, When, And How Much, Robert J. Woodward

School of Computing: Dissertations, Theses, and Student Research

Determining whether or not a Constraint Satisfaction Problem (CSP) has a solution is NP-complete. CSPs are solved by inference (i.e., enforcing consistency), conditioning (i.e., doing search), or, more commonly, by interleaving the two mechanisms. The most common consistency property enforced during search is Generalized Arc Consistency (GAC). In recent years, new algorithms that enforce consistency properties stronger than GAC have been proposed and shown to be necessary to solve difficult problem instances.

We frame the question of balancing the cost and the pruning effectiveness of consistency algorithms as the question of determining where, when, and how much of a higher-level …

Two Channel Sdm Communication System Simultaneously Operating At 10gb/S Using C-Band Transceivers, Han Wang

Theses and Dissertations

Increasing the bandwidth of optical fiber communications to cope with high-speed network traffic is an important goal for the communications industry. Therefore, optical communication is growing at a very rapid pace, including the multiplexing technology. Spatial domain multiplexing (SDM), also known as Space division multiplexing, is a Multi-Input Multi-Output (MIMO) architecture that can increase the data carrying capacity of optical fibers by multiple folds. SDM allows multiple channels of same wavelength to be transmitted in parallel over standard multi-mode fibers, where each SDM channel follows a different helical trajectory while traversing the length of the fiber that lead to unique …

Improving The Capacity Factor And Stability Of Multi-Mw Grid Connected Pv Systems With Results From A 1mw/2mwh Battery Demonstrator, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Conventional PV systems integrated with a battery connect the array and the energy storage unit to a dc-link through individual dc-dc converters for maximum power point tracking (MPPT) and battery charge control. This paper proposes a new system configuration, which connects the PV array and battery unit to the dc-link of the system inverter via a single dc-dc converter capable of simultaneously operating as a charge controller and MPPT device. This dc-dc converter is controlled such that it charges/discharges the battery with the amount of power required to maintain the PV array at its MPPT reference voltage. The proposed system …

Treatment Of Acid Orange 74 Wastewater And Sugar Wastewater By Low Cost Adsorbents, S. H. Madiraju, Yung-Tse Hung, Howard H. Paul

Civil and Environmental Engineering Faculty Publications

This study shows the treatment of combined binary mixture of Acid Orange 74 and sugar wastewater with peanut hull and orange peel as low-cost adsorbents. The performance of a combined adsorption-microfiltration process for the color removal is measured and compared using transmittance and absorbance indices at mechanical shaker mix level. This selected treatment procedure is among one of the most economical treatment alternatives to all technologies present now. The parameters studied during this research are analyzed using Langmuir and Freundlich isotherm models on low cost adsorbents. Conclusive results after the treatment are indicated in this paper at their optimum dosages …

Boron-Implanted Silicon Substrates For Physical Adsorption Of Dna Origami, Sadao Takabayashi, Shohei Kotani, Juan Flores-Estrada, Elijah Spears, Jennifer E. Padilla, Lizandra C. Godwin, Elton Graugnard, Wan Kuang, William L. Hughes

Materials Science and Engineering Faculty Publications and Presentations

DNA nanostructures routinely self-assemble with sub-10 nm feature sizes. This capability has created industry interest in using DNA as a lithographic mask, yet with few exceptions, solution-based deposition of DNA nanostructures has remained primarily academic to date. En route to controlled adsorption of DNA patterns onto manufactured substrates, deposition and placement of DNA origami has been demonstrated on chemically functionalized silicon substrates. While compelling, chemical functionalization adds fabrication complexity that limits mask efficiency and hence industry adoption. As an alternative, we developed an ion implantation process that tailors the surface potential of silicon substrates to facilitate adsorption of DNA nanostructures …

Engineered Nanoparticles Interact With Nutrients To Intensify Eutrophication In A Wetland Ecosystem Experiment, Marie Simonin, Benjamin P. Colman, Steven M. Anderson, Ryan S. King, Matthew T. Ruis, Astrid Avellan, Christina M. Bergemann, Brittany G. Perrotta, Nicholas K. Geitner, Mengchi Ho, Belen De La Barrera, Jason M. Unrine, Gregory V. Lowry, Curtis J. Richardson, Mark R. Wiesner, Emily S. Bernhardt

Plant and Soil Sciences Faculty Publications

Despite the rapid rise in diversity and quantities of engineered nanomaterials produced, the impacts of these emerging contaminants on the structure and function of ecosystems have received little attention from ecologists. Moreover, little is known about how manufactured nanomaterials may interact with nutrient pollution in altering ecosystem productivity, despite the recognition that eutrophication is the primary water quality issue in freshwater ecosystems worldwide. In this study, we asked two main questions: (1) To what extent do manufactured nanoparticles affect the biomass and productivity of primary producers in wetland ecosystems? (2) How are these impacts mediated by nutrient pollution? To address …

Executive Summary_Governance For A Changing Climate: Adapting Boston’S Built Environment For Increased Flooding, Stephanie Kruel, Rebecca Herst, David Cash

Sustainable Solutions Lab

As the impacts of climate change intensify, coastal cities like Boston face increasing threats from sea level rise, extreme precipitation, and storm surges. This report, produced by the Sustainable Solutions Lab at the University of Massachusetts Boston, examines the role of governance in preparing Boston’s built environment for these evolving risks. Building upon the foundational work of the Climate Ready Boston initiative, the report outlines critical governance functions necessary for climate adaptation, including institutional coordination, regulatory reform, community engagement, and data-driven decision-making. Emphasizing a multiscalar governance approach, it analyzes the tools available at local, regional, state, and federal levels and …

Shape-Based Separation Of Micro-/Nanoparticles In Liquid Phases, Behrouz Behdani, Saman Monjezi, Mason J. Carey, Curtis G. Weldon, Jie Zhang, Cheng Wang, Joontaek Park

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The production of particles with shape-specific properties is reliant upon the separation of micro-/nanoparticles of particular shapes from particle mixtures of similar volumes. However, compared to a large number of size-based particle separation methods, shape-based separation methods have not been adequately explored. We review various up-to-date approaches to shape-based separation of rigid micro-/nanoparticles in liquid phases including size exclusion chromatography, field flow fractionation, deterministic lateral displacement, inertial focusing, electrophoresis, magnetophoresis, self-assembly precipitation, and centrifugation. We discuss separation mechanisms by classifying them as either changes in surface interactions or extensions of size-based separation. The latter includes geometric restrictions and shape-dependent transport …

Governance For A Changing Climate: Adapting Boston’S Built Environment For Increased Flooding, Stephanie Kruel, Rebecca Herst, David Cash

Sustainable Solutions Lab

As the impacts of climate change intensify, coastal cities like Boston face increasing threats from sea level rise, extreme precipitation, and storm surges. This report, produced by the Sustainable Solutions Lab at the University of Massachusetts Boston, examines the role of governance in preparing Boston’s built environment for these evolving risks. Building upon the foundational work of the Climate Ready Boston initiative, the report outlines critical governance functions necessary for climate adaptation, including institutional coordination, regulatory reform, community engagement, and data-driven decision-making. Emphasizing a multiscalar governance approach, it analyzes the tools available at local, regional, state, and federal levels and …

Concrete Pavement Blowup Considering Generalized Boundary Conditions, Jaime Hernandez, Imad L. Al-Qadi

Civil and Environmental Engineering Faculty Research and Publications

An analytical expression for static stability of a rectangular slab with two simply supported and two elastically restrained edges is presented. The linear elastic isotropic slab can represent a rigid pavement resting on an elastic foundation and loaded by a uniform in-plane axial load per unit length along the edges. The partially restrained edges are connected to the ground by translational and rotational elastic springs; an appropriate magnitude of the springs can capture classical boundary conditions such as free, simply supported, and clamped edges. Results from classical boundary conditions and a finite-element model were used to validate the proposed stability …

A Comparison Of Special Category Light-Sport And Corresponding Type-Certificated Aircraft Safety, Carolina Anderson, Alan Stolzer, Douglas D. Boyd

Publications

The special category light sport airplane (light sport) sector of general aviation has grown 10-fold in as many years with solo operations requiring only a sports pilot's certificate. With little research on light sport airplane safety, the study objective was to compare light sport and type-certificated airplane accident rates.

Accidents were identified from the National Transportation Safety Board database. Statistics employed Poisson distribution/proportion analyses/Mann–Whitney U-tests.

For the 2009–2015 period, the light sport airplane accident rate (fatal/non-fatal combined) was > 15-fold higher than comparable type-certificated aircraft, undiminished over time. The excessive light sport airplane accident rate was associated with inferior airman experience …

Application Of Dupont’S Dirty Dozen Framework To Commercial Aviation Maintenance Incidents, Greg M. Mellema

Doctoral Dissertations and Master's Theses

This study examined the 12 preconditions for maintenance errors commonly known as the Dirty Dozen and applied them to actual incident and accident data provided by a participating airline (PA). The data provided by the PA consisted of Maintenance Event Reports (MERs) (reactive), Maintenance Operations Safety Assessment (MOSA) reports (proactive), and the results of the 2017 Maintenance Climate Awareness Survey (MCAS) (subjective). The MER and MOSA reports were coded by aviation maintenance subject matter experts (SMEs) using the 12 Dirty Dozen categories as the coding scheme, while the MCAS responses were parsed according to the precondition category they best represented. …

Microfluidic Electrical Impedance Spectroscopy, John J. Foley

Master's Theses

The goal of this study is to design and manufacture a microfluidic device capable of measuring changes in impedance valuesof microfluidic cell cultures. Tocharacterize this, an interdigitated array of electrodes was patterned over glass, where it was then bonded to a series of fluidic networks created in PDMS via soft lithography. The device measured ethanol impedance initially to show that values remain consistent over time. Impedance values of water and 1% wt. saltwater were compared to show that the device is able to detect changes in impedance, with up to a 60% reduction in electrical impedance in saltwater. Cells were …

An Overview Of Direct Current Distribution System Architectures & Benefits, Venkata Anand Prabhala, Bhanu Prashant Baddipadiga, Poria Fajri, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper examines existing and future direct current (DC) distribution systems with a wide range of applications in data centers, telecommunication systems, commercial buildings, residential homes, electric vehicles, spacecraft, and aircrafts. DC distribution systems have many advantages and disadvantages over their alternating current (AC) counterparts. There are a few surviving examples of DC distribution systems; among them are the telecommunication systems and data centers that use the low-voltage 48 Vdc systems. However, recently, there has been a move towards higher DC bus voltages. In this paper, a comparative study of different DC distribution architectures and bus structures is presented and …

Analysing Online User Activity To Implicitly Infer The Mental Workload Of Web-Based Tasks Using Defeasible Reasoning, Paul Mara

Dissertations

Mental workload can be considered the amount of cognitive load or effort used over time to complete a task in a complex system. Determining the limits of mental workload can assist in optimising designs and identify if user performance is affected by that design. Mental workload has also been presented as a defeasible concept, where one reason can defeat another and a 5-layer schema to represent domain knowledge to infer mental workload using defeasible reasoning has compared favourably to state-of-the-art inference techniques. Other previous work investigated using records of user activity for measuring mental workload at scale using web-based tasks …

Bs News September/October

Building Services Engineering

No abstract provided.

Accurate Flexible Refinement Of Atomic Models Against Medium-Resolution Cryo-Em Maps Using Damped Dynamics, Julio A. Kovacs, Vitold E. Galkin, Willy Wriggers

Mechanical & Aerospace Engineering Faculty Publications

Background: Dramatic progress has recently been made in cryo-electron microscopy technologies, which now make possible the reconstruction of a growing number of biomolecular structures to near-atomic resolution. However, the need persists for fitting and refinement approaches that address those cases that require modeling assistance.

Methods: In this paper, we describe algorithms to optimize the performance of such medium-resolution refinement methods. These algorithms aim to automatically optimize the parameters that define the density shape of the flexibly fitted model, as well as the time-dependent damper cutoff distance. Atomic distance constraints can be prescribed for cases where extra containment of parts of …

Assessing The Relationship Between Groundwater Nitrate Concentrations And Environmental Variables Through Repeat Sampling And Statistical Machine Learning: Dutch Flats, Nebraska, Martin Wells

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Nitrate-contaminated aquifers are common in landscapes dominated by agricultural land use. Health concerns related to consuming nitrate-contaminated groundwater are well documented and continued research aimed at decreasing concentrations is critical. A 1990s U.S. Geological Survey (USGS) study focused on groundwater characteristics in the Dutch Flats area of western Nebraska. Agricultural-related practices were determined to largely influence groundwater recharge and nitrate concentrations ([NO₃^-]). Since the conclusion of the USGS study, a transition to more efficient irrigation technology has been observed in this region. The emphasis of this 2016 study was to resample several well nests examined in 1998 …

The Design, Test And Evaluation Of A Sensing System For Process Analytical Technology (Pat), Trevor Murphy

Theses

Increased globalisation and competitiveness has given rise to a more dynamic and diverse global market that has begun to place incredible strain on manufacturing supply chains. Conventional manufacturing methods such as the batch manufacturing methods employed largely by the materials processing industries i.e. pharmaceuticals, polymers and magnesium processing plants are ill-suited to cope with the demands of today. As products evolve with technological advancements they become more complex to produce and require alternative approaches to manufacturing to ensure product quality while reducing costs and increasing manufacturing efficiencies.

A potential solution to the growing demands on today’s supply chain is process …

Design Of Wind Turbine Tower Height And Blade Length: An Optimization Approach, Ryan Wass

Mechanical Engineering Undergraduate Honors Theses

The wind industry is a fast growing market and is quickly becoming competitive with traditional non-renewable energy resources. As with any developing industry, research must continually be redefined as more complex understandings of design variables are learned. Optimization studies are common ways to quickly refine design variable selections. Historical wind turbine data shows that the tower hub height to rotor diameter ratio scales almost linearly. However there is no specific rule that dictates the optimum hub height for a given diameter. This study addresses this question by using an Excel based optimization program to determine the height to diameter ratio …

Modeling Vocal Fold Intravascular Flow With Synthetic Replicas, Aaron David Terry

Theses and Dissertations

Communication by voice is foundational in our society and many rely on their voices for their occupations. Voice disorders affect a significant number of individuals each year, and diagnosis and treatment improvements are therefore sought via advancements in voice research. Contained in this thesis is a description of work intended to contribute to vocal fold research by using synthetic, self-oscillating vocal fold replicas to study the impact of replica vibration on perfusion fluid flow through the replica. Methods for manufacturing vocal fold replicas containing imbedded channels allowing for fluid perfusion are discussed. Experimental procedures developed for delivering perfusion fluid to …

Visual Servoing For Precision Shipboard Landing Of An Autonomous Multirotor Aircraft System, Jesse Stewart Wynn

Theses and Dissertations

Precision landing capability is a necessary development that must take place before unmanned aircraft systems (UAS) can realize their full potential in today's modern society. Current multirotor UAS are heavily reliant on GPS data to provide positioning information for landing. While generally accurate to within several meters, much higher levels of accuracy are needed to ensure safe and trouble-free operations in several UAS applications that are currently being pursued. Examples of these applications include package delivery, automatic docking and recharging, and landing on moving vehicles. The specific problem we consider is that of precision landing of a multirotor unmanned aircraft …