Engineering Commons^™

Thermodynamic Model Of Co2 Deposition In Cold Climates, Sandra K. S. Boetcher, Ted Von Hippel, Matthew J. Traum

Publications

A thermodynamic model, borrowing ideas from psychrometric principles, of a cryogenic direct-air CO2-capture system utilizing a precooler is used to estimate the optimal CO2 removal fraction to minimize energy input per tonne of CO2. Energy costs to operate the system scale almost linearly with the temperature drop between the ingested air and the cryogenic desublimation temperature of CO2, driving siting to the coldest accessible locations. System performance in three Arctic/Antarctic regions where the proposed system can potentially be located is analyzed. Colder ambient temperatures provide colder system input air temperature yielding lower CO2 removal energy requirements. A case is also …

Wall-Jet Turbulence And Mixing Control By Way Of A Pulsed Inlet Velocity, Cristale D. Garnica Vallejo

Doctoral Dissertations and Master's Theses

Understanding wall-jet-induced turbulence and mixing is an important challenge in modern engineering, as drag reduction and mixing enhancement are attainable by modifying the flow development. Simulations are performed to investigate the effect on skin friction and flow mixing due to introducing controlled perturbations, at the initial shear layer of a planar wall-jet using jet inlet cyclic pulsing. The billow production by the Kelvin-Helmholtz instability, the instability that drives turbulence in a wall-jet, is modified by the excitation of the inlet velocity profile by a sine wave perturbation. Two types of wall-jet simulations are carried out, a two-dimensional compressible case at …

Where We Are With Enterprise Architecture, Leila Halawi, Richard Mccarthy, James Farah

Publications

Enterprise architecture has been continuously developing since the mid-1980s. Although there is now 35 years of research and use, there is still a lack consistent definitions and standards. This is apparent in the proliferation of so many different enterprise architecture frameworks. Despite the significant body of research, there is a need for standardization of terminology based upon a meta-analysis of the literature. Enterprise architecture programs require commitment throughout an organization to be effective and must be perceived to add value. This research offers an initial basis for researchers who need to expand and continue this research topic with an actual …

Fatigue Issues And Mitigation Strategies In Collegiate Aviation, Flavio A. C. Mendonca Ph.D., Julius Keller, Erik Levin, Aaron Teo

Publications

The reduction of fatigue-related accidents has been in the NTSB most wanted list since 2016 (NSTB, 2019).

Most research studies have focused on fatigue identification and management within the commercial and/or military aviation environments (Caldwell et al., 2009; Gawron, 2016; Sieberichs & Kluge, 2016).

However, collegiate aviation may be the most challenging in terms of fatigue mitigation. Flight instructors and students often have schedules which may increase the risks for fatigue.

Mitigating The Risk Of Bird Strikes: The Use Of Virtual Reality During Flight Training, Flavio A. C. Mendonca Ph.D., Julius Keller Ph.D., Chien-Tsung Lu, Chenyu Huang Ph.D.

Publications

There were 193,969 wildlife strikes in the US from 1990 through 2017. Wildlife strikes annually cost the US civil aviation industry, on average, $186 million in monetary losses and 111,284 hours of aircraft downtime (Dolbeer & Begier, 2019). According to the Federal Aviation Administration (FAA), Aeronautical Decision-Making (ADM) is a systematic approach that encourages pilots to identify hazards and manage risks (FAA, 2016). Additionally, it helps aviators to make timely and safe decisions. Even though it is practically impossible to eliminate the risk of bird strikes, crewmembers play a vital role in the accident prevention process (Mendonca, Carney, & Fanjoy, …

Development Of A Research Spacecraft Test-Bed With Implementation Of Control Laws To Compensate Undesired Dynamics, Yomary Angélica Betancur Vesga

Doctoral Dissertations and Master's Theses

The development of research spacecraft systems has a significant impact on the preparation and simulation of future space missions. Hardware, software and operation procedures can be adequately tested, validated and verified before they are deployed for the actual mission. In this thesis, a spacecraft vehicle test-bed named Extreme Access System (EASY) was developed. EASY aims at supporting validation and verification of guidance, navigation and control algorithms. Description of EASY spacecraft systems, sub-systems and integration is presented in this thesis along with an analysis of results from numerical simulation and actual implementation of control laws. An attitude control architecture based on …

Effects Of Musical Ability On Flight Planning, Situational Awareness, And Flight Path Deviations, Andrew P. Henry

Doctoral Dissertations and Master's Theses

Numerous studies have been conducted on music education and the benefits that learning an instrument has on the brain. However, there is little research that connects a pilot’s ability to play an instrument to a pilot’s ability to fly an airplane. When learning an instrument, students learn non-musical abilities, such as executive functions, which may correspond with the skills necessary to be a good pilot. The purpose of this study was to find a relationship between learning a musical instrument and pilot performance, specifically related to flight planning, situational awareness, and flight path deviations. This study was a quasi-experimental design …

The Effectiveness Of Augmented Reality For Astronauts On Lunar Missions: An Analog Study, Godfrey Valencio D’Souza

Doctoral Dissertations and Master's Theses

The uses of augmented reality and head-up displays are becoming more prominent in industries such as aviation, automotive, and medicine. An augmented reality device such as the Microsoft HoloLens can project holograms onto the user’s natural field of view to assist with completion of a variety of tasks. Unfortunately, only a little research and development has begun in the space sector for astronauts using these head-up displays. Future lunar missions could incorporate augmented reality for astronauts to ease task load and improve accuracy. This study evaluated the usability, subjective workload, and task performance of 22 participants using the Microsoft HoloLens …

Numerical Treatment Of Schrödinger’S Equation For One-Particle And Two-Particle Systems Using Matrix Method, Spatika Dasharati Iyengar

Doctoral Dissertations and Master's Theses

With an increased interest in accurately predicting aerothermal environments for planetary entry, recent researches have concentrated on developing high fidelity computational models using quantum-mechanical first principles. These calculations are dependent on solving the Schrödinger equation using molecular orbital theory techniques. They are either approximate solutions to actual equations or exact solutions to approximate equations. Exact solutions have not found favor due to the computational expense of the problem. Hence, a novel numerical approach is developed and tested here using linear algebraic matrix methods to enable precise solutions.

The finite-difference technique is used to cast the Time-Independent Schrödinger equation (TISE) in …

In-Situ Measurement Of Resin Shrinkage For Aerospace Components, Samarth Motagi

Doctoral Dissertations and Master's Theses

Resin shrinkage due to chemical changes and thermal gradients plays an important role in the residual stress evolution during composite manufacturing. In this thesis, we develop a new in-situ experimental approach for measuring resin shrinkage during curing with the help of digital image correlation (DIC) instrumented on a specially designed autoclave with borosilicate viewports. The images of the resin sample are captured at regular intervals with the help of DIC to measure the displacement and strains during the curing process. We utilize this method for a comparative analysis of resin shrinkage in two common aerospace epoxies, Epoxy 105 and EPON …

Adaptive Learning Terrain Estimation For Unmanned Aerial Vehicle Applications, Pedro L. Vergara Garcia

Doctoral Dissertations and Master's Theses

For the past decade, terrain mapping research has focused on ground robots using occupancy grids and tree-like data structures, like Octomap and Quadtrees. Since flight vehicles have different constraints, ground-based terrain mapping research may not be directly applicable to the aerospace industry. To address this issue, Adaptive Learning Terrain Estimation algorithms have been developed with an aim towards aerospace applications. This thesis develops and tests Adaptive Learning Terrain Estimation algorithms using a custom test benchmark on representative aerospace cases: autonomous UAV landing and UAV flight through 3D urban environments. The fundamental objective of this thesis is to investigate the use …

Numerical Investigation Of Scaling Effects Of A Ramjet-Powered Projectile, Arjun Jaishankar Vedam

Doctoral Dissertations and Master's Theses

Ramjet flowpath miniaturization is a potentially useful technology for integration into munitions to increase range, accuracy, and lethality. The emphasis of this effort is to numerically characterize the performance of a miniature hydrogen-fueled and ethylene-fueled ramjet flowpath during Mach 3 and Mach 3.5 sea-level flight. The effect of geometric scale on ramjet performance is evaluated using high-fidelity RANS CFD models. Sensitivity to nonequilibrium laminar and turbulence-limited chemistry, and transitional turbulence treatments are evaluated. The physical sources of small scale performance limitations are identified for both fuel types. Finally, flowpath integration for small-scale applications is briefly addressed.

Multirotor Uas Sense And Avoid With Sensor Fusion, Jonathan Mark Buchholz

Doctoral Dissertations and Master's Theses

In this thesis, the key concepts of independent autonomous Unmanned Aircraft Systems (UAS) are explored including obstacle detection, dynamic obstacle state estimation, and avoidance strategy. This area is explored in pursuit of determining the viability of UAS Sense and Avoid (SAA) in static and dynamic operational environments. This exploration is driven by dynamic simulation and post-processing of real-world data. A sensor suite comprised of a 3D Light Detection and Ranging (LIDAR) sensor, visual camera, and 9 Degree of Freedom (DOF) Inertial Measurement Unit (IMU) was found to be beneficial to autonomous UAS SAA in urban environments. Promising results are based …

Fuel Efficient Control Design And Constrained Motion Analysis For Spacecraft Coulomb Formation In Elliptic Chief Orbits, Muhammad Wasif Memon

Doctoral Dissertations and Master's Theses

The use of Coulomb force has been analyzed in recent years to provide propulsion in space for various applications. Coulomb formation can also be utilized to make close formation spacecraft missions fuel efficient. In this study, the Coulomb formation of two craft is studied in elliptic chief orbits for two formation geometries. The first formation requires both spacecraft to be aligned along the nadir (radial) direction and the second formation requires both spacecraft to maintain a constant separation distance relative to each other while each spacecraft rotates freely on the surface of a sphere with the ratio of the radii …

A Step Toward Ending Long Airport Security Lines: The Modified Boarding Pass, Joel Lee

Doctoral Dissertations and Master's Theses

Anyone who has traveled by air has most likely experienced long airport security lines. Yet not much is known about its cause because few have considered if passengers have created this problem for themselves. The present study attempts to fill this research gap by suggesting that when passengers are not well-prepared for security screening, they delay the process by making mistakes and not complying with procedures. This lack of preparedness can be attributed to several shortcomings of security signposts. This study proposes the use of a modified boarding pass as an alternative form of signage to help passengers better prepare …

Autonomous Autorotation Of A Tilt-Rotor Aircraft Using Model Predictive Control, Elias Wilson

Doctoral Dissertations and Master's Theses

Tilt rotor vehicles are governed by FAA laws also used for conventional helicopters, which require autorotational maneuvering and landing given a total power failure. With low inertia rotors and high disk loading of tilt rotor vehicles, this already difficult task becomes significantly more challenging. In this work, a model predictive controller is developed to autonomously maneuver and land a tilt rotor given complete power loss. A high fidelity model of a tilt rotor vehicle is created and used to simulate the vehicle dynamics and response to control inputs. A reduced order dynamic model is used within a model predictive control …

Fuel Shortages During Hurricanes: Epidemiological Modeling And Optimal Control, Sabique Ul Islam

Doctoral Dissertations and Master's Theses

Hurricanes are powerful agents of destruction with significant socioeconomic impacts. A persistent problem due to the large-scale evacuations during hurricanes in the southeastern United States is the fuel shortages during the evacuation. Fuel shortages often lead to stranded vehicles and exacerbate the evacuation efforts. Computational models can aid in emergency preparedness and help mitigate the impacts of hurricanes. In this thesis, the hurricane fuel shortages are modeled using the Susceptible-Infected-Recovered (SIR) epidemic model. Crowd-sourced data corresponding to Hurricane Irma and Florence are utilized to parametrize the model. An estimation technique based on Unscented Kalman filter (UKF) is employed to evaluate …

Computational Model For Pedestrian Movement And Infectious Diseases Spread During Air Travel: A Molecular Dynamics-Like Numerical Approach, Pierrot Derjany

Doctoral Dissertations and Master's Theses

There is direct evidence of the transmission of fatal infectious pathogens in large human gatherings. Air transportation is no exception. The mixing of susceptible and infectious individuals in this high-density man-made environment involves pedestrian movement which is generally not taken into account in modeling studies of disease dynamics. This thesis addresses this problem through a multiscale model that combines pedestrian dynamics with stochastic infection spread models. This generic model is applicable to several directly transmitted diseases. Through this multiscale framework, the effectiveness of certain layout and strategies in suppressing the disease spread in highly crowded locations such as airplanes, airports …

Security Of The Internet Of Things: Vulnerabilities, Attacks And Countermeasures, Ismail Butun, Houbing Song, Patrik Osterberg

Publications

Wireless Sensor Networks (WSNs) constitute one of the most promising third-millennium technologies and have wide range of applications in our surrounding environment. The reason behind the vast adoption of WSNs in various applications is that they have tremendously appealing features, e.g., low production cost, low installation cost, unattended network operation, autonomous and longtime operation. WSNs have started to merge with the Internet of Things (IoT) through the introduction of Internet access capability in sensor nodes and sensing ability in Internet-connected devices. Thereby, the IoT is providing access to huge amount of data, collected by the WSNs, over the Internet. Hence, …

How Airport Construction Will Evolve With The Increased Effects Of Climate Change, Xavier M. Ashley

Beyond: Undergraduate Research Journal

This report addressed the effects rising global temperatures resulting from climate change have had on flight operations in their entirety. The research objective was to discover what methods could enhance climate adaptation in airport construction, as higher mean-surface temperatures have an increasingly negative effect on aircraft performance. The findings would primarily be of interest to the Federal Aviation Administration (FAA) Primary Office presiding over the planning and development of airports. Overall, the report provided a comprehensive analysis of global warming’s effects on aviation, including the implications of degraded aircraft performance and sea-level rise for coastal airports. Additionally, it examined comparative …

Automated Dynamic Detection Of Self-Hiding Behaviors, Luke Baird

Student Works

Certain Android applications, such as but not limited to malware, conceal their presence from the user, exhibiting a self-hiding behavior. Consequently, these apps put the user’s security and privacy at risk by performing tasks without the user’s awareness. Static analysis has been used to analyze apps for self-hiding behavior, but this approach is prone to false positives and suffers from code obfuscation. This research proposes a set of three tools utilizing a dynamic analysis method of detecting self-hiding behavior of an app in the home, installed, and running application lists on an Android emulator. Our approach proves both highly accurate …

Correct Delay Code Assignment, Alessandro Conconi, Anderson Da Silva Serafim, Vitor Cordeiro Silva, Thais Vieira Haberli

Graduate Student Works

The air transport market requires high investments, has elevated risks, and low financial return. The competition requires airlines to differentiate themselves by offering better services. On-time Performance (OTP) is an essential service; lack of punctuality affects company costs and revenues. An on-time company generates more satisfaction for travelers, retaining them. Flight delays are identified and reported by airlines through delay codes that are standardized by IATA.

A detailed and specific analysis of an airline's processes was performed to verify the quality of delay code allocation information. It also features the complete mapping of this company's delay code allocation processes and …

A Better Approach For Mishandled Bags Industry Measure, Ana Caroline Costa, Daniel B. Ravagnani, Domenico Giuseppe Valente, Vitor Coletti Fernandes

Graduate Student Works

Since 1987, the US Department of Transportation (DOT) has ordered US airlines to report baggage handling statistics. The Code of Federal Regulations (CFR), requests each U.S. carrier to report monthly the total number of passengers enplaned, and the total number of mishandled baggage reports (MBR), including lost, pilfered, damaged and delayed baggage. The U.S. DOT also created a mishandled-baggage rate, which represents the total number of MBRs divided by 1,000 passengers enplaned. This KPI is monthly published at the Air Travel Consumer Report. And it is used worldwide to make comparisons between regions, airports, and airlines, characterizing efficiency and consistency …

Contingency Fuel Reduction, Diogo Youssef, Fabiano Gomes De Oliveira, Joao Centeno, Luciano Figueiredo Vale De Oliveira

Graduate Student Works

This project reviews the minimum fuel regulations for commercial passenger flights in different countries and intends to scientifically support a change in the existing contingency fuel requirement regulation in Brazil. This change represents fuel savings for Brazilian air operations, and it deploys into competitive advantage for Brazilian airlines compared to foreign air operators. The objective of this project is to provide the Brazilian civil aviation regulators with the necessary data to justify the reduction of the contingency fuel values from the current 10% to 5%. This project bases the analysis on the historical data of fuel planning and fuel consumption …

Automated Disruption Assistance, Christian Gruber Delamare, Douglas Cabrera Lopes, Patrice Ramos, Raioni De Oliveira Santos

Graduate Student Works

During the last decade, commercial aviation in Brazil has grown significantly, overcoming the number of 100 million passengers per year. The intense operation represents a challenge for the air carriers, especially during flight disruptions. In Brazil, besides the re-accommodation of the passengers into other flights, under certain circumstances, the ANAC 400 resolution requires the airlines to provide a series of material assistance. Meal, transport, and hotel make part of the exigences stated by the ANAC 400.

Our study aims to analyze the current process that is mainly manual and propose to automatize several steps through a self-service solution. The researchers …

A Study On Spare Aircraft In Brazilian Airlines, Clarissa Pinheiro Pereira, Eduardo Sakashita, Eliudes Del Grande, Guilherme Bevilacqua

Graduate Student Works

All around the globe, the airlines struggle to sustain profitability. They are deeply affected by the region’s economy. It goes from the fuel price and exchange rate to the level of employment and average salary. That makes it imperative to control the cost, and also to balance very well the cost and level of service. Aircraft utilization is one KPI that measures productivity. Once the airline has a high aircraft utilization, it means that the resource has been productive, hence more cost-efficient.

On the other hand, flight cancelations and delays result in costs and passengers’ dissatisfaction. In Brazil, there is …

An Evaluation Of The Operational Restrictions Imposed To Congonhas Airport By Iac 121-1013, Glanski O.C. Pacheco Jr., Marcus Camargo

Graduate Student Works

The objective of this study is to propose a review of the operational restrictions imposed on Congonhas airport by IAC 121-1013, seeking a balance between flight safety and operational efficiency.

The researchers calculated the landing performance (using specific software), taking into account particular aircraft system failures that increase landing distance. The results indicated that the measures imposed by the IAC have little or no effect on the operational safety increase. Additionally, the restrictions created operational complexity for the airport and reduced its efficiency by impacting airline costs. At the end of the study, the researchers suggest a reissue of the …

Training Synergy, Andre Vieira Caputo, Everton Amieiro, Lucio De Araujo Alves, Renan Dapena Roveran

Graduate Student Works

Brazil is facing a growth in the airline industry where all the major airlines are currently hiring pilots, flight attendants, and mechanics. One of the challenges of those airlines is to provide training for all these professionals. Many times they do not have instructors or classrooms available. It is crucial for the airlines to promote faster and better training, to reduce cost, save time and resources to prepare a better professional. With this capstone, we want to show the possibility of increasing the cost performance of airline training by providing alternatives to airlines. The idea is to promote synergy between …

Engine Light Repair Shop Evaluation For A Brazilian Airline, Gustavo Henrique Melhado Trevilatto, Marcelo Teodoro Miranda

Graduate Student Works

The maintenance cost of a commercial aircraft comprises airframe, components, and engines. The most expensive of them are engines, which may represent up to 60% of an aircraft cost, and therefore will have a significant impact on any airline finance. As a result, engine fleet maintenance management is crucial for any airline sustainability. Apart from heavy maintenance where life limited parts are replaced and its performance restored, aircraft engines are often required to come off wing for light repair due to operational issues like foreign object damage, high oil consumption, and vibration issues. In other cases, even though being operational, …

Large Deformable Soft Actuators Using Dielectric Elastomer And Origami Inspired Structures, Jangho Park

Doctoral Dissertations and Master's Theses

There have been significant developments in the field of robotics. Significant development consists of new configurations, control mechanisms, and actuators based upon its applications. Despite significant improvements in modern robotics, the biologically inspired robots has taken the center stage. Inspired by nature, biologically inspired robots are called ‘soft robots’. Within these robots lies a secret ingredient: the actuator. Soft robotic development has been driven by the idea of developing actuators that are like human muscle and are known as ‘artificial muscle’. Among different materials suitable for the development of artificial muscle, the dielectric elastomer actuator (DEA) is capable of large …