Engineering Commons^™

Trend Analysis And Operational Performance Indicators In The U.S. Airline Industry, Jacqueline R. Luedtke, Brent D. Bowen

Aeronautical Science - Prescott

Operational performance of the U.S. airline industry has been monitored for the past 25 years by a unique quantitative model of key metrics. As the nation’s most comprehensive study of airline performance and quality in existence, the National Airline Quality Rating (http://airlinequalityrating.com) sets the industry standard, providing consumers and industry watchers a means to compare performance quality among airlines using objective performance-based data. No other airline study in the country is based on performance measures. Criteria included in the Airline Quality Rating (AQR) report are screened to meet two basic elements: (1) they must be readily obtainable from …

Characterization And Low-Dimensional Modeling Of Urban Fluid Flow, Dietmar Rempfer, Candace Wark, Bruno Monnier, Sriharsha Kandala

Publications

This report describes work that was done under AFOSR Contract Number FA9550-11-1-0056, studying the structure of a model urban boundary layer flow. The model geometry consisted of a set of plexiglass blocks, and the flow around this geometry was studied both experimentally as well as computationally. For the experiment, a Stereoscopic Particle Image Velocimetry (SPIV) method was developed that allows for a three-dimensional description of this urban flow, and helps gain insight into the characteristic flow structures in the streets and canyons of our model urban geometry. On the computational side, a new spectral-element code was developed that was demonstrated …

Effect Of Air Carrier Restructuring Strategies On Post-Bankruptcy Performance, Harold Dale Townsend

Doctoral Dissertations and Master's Theses

Air carrier bankruptcy is a common occurrence in the aviation industry. However, there is a paucity of research on the topic of air carrier restructuring during the post-bankruptcy period. General restructuring literature has identified four types of actions: operational, financial, managerial, and portfolio. The purpose of this study was to partially fill the large literature gap in the area of air carrier post-bankruptcy performance through theoretical and practical contributions.

A multilevel exploratory factor analysis was conducted to explore whether the same restructuring areas were found in air carrier specific metrics. All four restructuring areas were found in the factor analysis. …

National Culture: Understanding The Impact Of Cross-Culture On Airline Pilots' Safety Performance In The Middle-East And North Africa (Mena) Region, Shareef Abdulla Kaddas Al-Romaithi

Doctoral Dissertations and Master's Theses

The continuous expansion of Middle Eastern airlines has created a pilot shortage. Since the local pilot population in the Middle East is relatively small, airlines have been relying on foreign pilots to satisfy their operational requirements. Consequently, pilots with diverse cultural perspectives have been operating together. In order to manage this cultural diversity and ensure safe operations, airlines have been applying a number of training and operational strategies such as Crew Resource Management (CRM) with emphasis on adherence to Standard Operating Procedures (SOP). However, CRM was designed and implemented by North Americans as a solution for human factor intricacies among …

Investigation Of Pulse Detonation Engine Flow Conditions For Turbomachinery Integration, Luis Estefano Ferrer-Vidal EspañA-Heredia

Doctoral Dissertations and Master's Theses

Pressure gain combustion has been known to be more thermodynamically efficient than its constant pressure counterpart, which employs deflagration. Integration of pressure gain combustors into gas turbine engines has been and still is one of the most important challenges facing the gas turbine industry. Pressure gain combustion devices are inherently unsteady. This unsteadiness affects turbomachinery components designed using steady operation assumptions, and results in mechanical inefficiencies which could outweigh the thermal efficiency benefits. Understanding of turbine components specifically made to operate in the exhaust conditions provided by a pressure gain combustor may yield new turbine design paradigms. As a first …

Reduction Of Secondary Flow Losses In A Turbine For Use In Man-Portable Power Generation, Andrew J. Yatsko

Doctoral Dissertations and Master's Theses

As the world has moved into a more energy-demanding environment, there has been the push for higher energy density in a smaller package. One of the potential solutions is through the application of a gas turbine engine; yet the challenge is extracting the energy efficiently through the small components. The focus of the research is on the turbine components and how the secondary flow losses from the generated airfoil shapes can be reduced to improve component performance. One of the secondary flow loss items to be addressed is the generation of the Horseshoe Vortex. The Horseshoe Vortex is an aerodynamic …

The Effects Of Rewards On The Ability Of An Autonomous Uav Controlled By A Reinforcement Learning Agent To Accomplish A Target Localization Task, Hemali Dinesh Virani

Doctoral Dissertations and Master's Theses

The need for Unmanned Aerial System (UASs) is increasing in the fields of science, security, military and others. With an increasing number of challenges faced by mankind the need for system with advance autonomous and intelligent capabilities is growing rapidly. The required intelligent behavior can be achieved in an unmanned system with machine learning methods such as Reinforcement Learning (RL) theory. This theory presents algorithms which have the capability to learn how to adapt to its environment. Using RL methods, autonomous systems have the ability to use past experiences to improve future mission performance. In this research, the effects of …

The Use Of A Real Time Online Class Response System To Enhance Classroom Learning, Lulu Sun

Publications

A real time online class response system was used in class to quickly query student population’s grasp of concepts, engage class participation, check their attendance, and clarify any misconceptions. The biggest challenges for the instructor are time needed to learn the new system, creating effective concept questions, adequate coverage of course material, and ability to respond to instantaneous student feedback. Student challenges include increased confusion if inappropriate wording for the questions, and a negative reaction to the approach in general. Overall this is a highly flexible use of interactive technology for engaging students in any discipline during the class time.

Processus De Décision Et Complexité: Le Feu De Yarnell Hill Du 30 Juin 2013 [Decision-Making Processes And Complexity: The Yarnell Hill Fire Of June 30th, 2013], Karim Hardy, Louise K. Comfort

Publications

Re-forming the information stream in decision processes after severe accidents allows scientists aRecréer les flux d’information au sein des processus de décision après une catastrophe permet aux chercheurs ainsi qu’aux décideurs d’identifier les points à partir desquels une action défaillante débute ainsi que les écarts dans les processus d’information qui pourraient être corrigés afin de réduire les futurs lors de futurs incidents. Le 30 juin 2013, le feu de Yarnell Hill en Arizona (Etats-Unis) évolue rapidement dans des conditions environnementale et managériale très difficiles menant à l’effondrement de la stratégie de lutte et à la perte de dix-neuf sapeurs-pompiers de …

Tales Of A Combat Advisor In Iraq, Jerry Kidrick

ERAU Prescott Aviation History Program

In 2010, Army aviator Jerry Kidrick was mobilized from the Alaska National Guard to lead a team of Combat Advisors in Iraq. For 16 months in Basra, he advised the Iraqi Army on counter-insurgent actions. He also acted as liaison between the US State Dept.,CIA and US Commanders. He will discuss his experiences and how the Iraqi military assumed a greater counter-insurgent role under Operation New Dawn.

On Uav Robust Nonlinear Control In Presence Of Parametric Uncertainties, Vladimir V. Golubev, William Mackunis

Publications

We examine a new robust nonlinear flight control technology that employs an array of synthetic-jet micro-actuators embedded in UAV wing design in order to completely eliminate moving parts (such as ailerons) thus greatly enhancing maneuverability required for small fixed-wing air vehicles operating, e.g., in tight urban environments. Estimated fast response times are critical in mitigating gust effects while greatly improving flight stability and control. The new controller design is particularly advantageous for high levels of uncertainty and nonlinearity present both in the unsteady flowpath environment and in the embedded actuator’s response. The current work focuses on a benchmark case of …

Natural Convection From Circular Cylinders, Sandra K. S. Boetcher

Publications

Chapter 1

Natural convection heat transfer from circular cylinders in quiescent environments is a subject which has been studied extensively. Although a well-established topic, to the best knowledge of the author no single source of reference is found for natural convection from circular cylinders for varying orientations (horizontal, vertical, and inclined). This book attempts to be a reference for Nusselt number correlations for circular cylinders of all inclinations including horizontal and vertical.

Evaluation And Flight Assessment Of A Scale Glider, Alvydas Anthony Civinskas

Doctoral Dissertations and Master's Theses

The objective of this project is to do a flight assessment of a Phoenix K8B radio controlled glider to see what process is needed to verify its glide slope and stability characteristics. The flight test analysis, plus a computational fluid dynamics analysis, and an industry-like component build-up aerodynamic analysis were done to provide comparable estimates for the aircraft glide slope. A stability and control derivative analysis was also completed and compared using SURFACES, USAF Datcom, and MIT AVL software. The glide slope estimate and stability and control derivatives obtained from flight test data showed considerable range and uncertainty. Potential sources …

Execution Of A Hybrid Vehicle Controls Development Effort Utilizing Model-Based Design, Hardware-In-The-Loop Testing, Agile Scrum Methods And Requirements Engineering, Derek Simon Bonderczuk

Doctoral Dissertations and Master's Theses

Modern hybrid vehicles require sophisticated supervisory control systems in order to realize competitive efficiency gains. Processes such as model-based design, HIL simulation and Agile Scrum methods can allow for quicker and less costly development of a complex product. The design of a supervisory control system for a prototype PHEV vehicle was executed with the intent of developing a mule vehicle into a 99% production ready vehicle. The control system design process was carried through from requirements definition to operating parameter optimization of utilizing model-based design, HIL simulation and the Scrum model. A prototype vehicle that has a fully functioning hybrid …

Investigation Of Traditional And Alternate Living Hinge Designs For Fused Deposition Modeling Additive Manufacturing Process, Cassandra Sue Gribbins

Doctoral Dissertations and Master's Theses

A manuscript-style thesis composed of three studies covered the application of living hinge designs in the additive manufacturing process of fused deposition modeling. Initial research included comparing numerical and analytical linear analyses on a traditional living hinge design. The second research consisted of tensile testing for the material properties of the Acrylonitrile Butadiene Styrene (ABS) used in fused deposition modeling (FDM) process by the MakerBot 2X as well as adjusting the traditional design to be printed. The third study explored alternate living hinge designs that utilize the geometric freedom provided by additive manufacturing to more evenly distribute stress across the …

Unsteady Viscous Cavity Flow Using Computational Fluid Dynamics, Chandramouli Vadlamudi

Doctoral Dissertations and Master's Theses

The problem of unsteady viscous incompressible flow in a two-dimensional cavity is treated using the unsteady incompressible Navier-Stokes equations with various initial and boundary conditions. First the case of a square cavity with one inlet and one outlet is treated in steady and unsteady flows. The software package ANSYS FLUENT was used in the CFD simulations. This approach captures the appearance of separation bubbles and vortex formation inside the cavity. Steady state flows are also obtained from the unsteady simulations after convergence of the time dependent solutions. Then the case of a cavity with a synthetic jet and two outlets …

Potential And Technological Advancement Of Biofuels, Rajee Olaganathan, Fabian Ko Qui Shen, Lim Jun Shen

Publications

This scientific paper examines the feasibility of biofuels as a solution to the world‟s energy crisis. It studies the development of the four different generations of biofuel that have been discerned over the years, determining the pros and cons of each. The paper further investigates the issues concerning each generation, and determines how their successors have solved and improved on those problems. In order to give the reader an unbiased perspective, the paper studies both general advantages and disadvantages that encompasses social, economic and environmental impacts. Research and development on the first two generations of biofuels have matured, and case …

Axial Compressor Design With Counter-Rotation And Variable Rpm For Stall Mitigation, Madhur Tiwari

Doctoral Dissertations and Master's Theses

Compressor Stall, an aerodynamic instability due to abnormal air flow in the compressor resulting in loss of total pressure and compressor performance. One of the reasons of compressor stall is due to rise in static back pressure at compressor exit which may result from an imbalance of incidence angle at the rotor and stator and rotational speed. The paper presents the results of a new axial compressor design with counter rotation and variable RPM. Counter-Rotation is used to push compressor performance during stall by moving the operating point away from surge line with a higher pressure ratio rise. Initially an …

Variable Viscosity Condition In The Modeling Of A Slider Bearing, Kedar Nath Uprety, S.C. Mancas

Publications

To reduce tear and wear of machinery lubrication is essential. Lubricants form a layer between two surfaces preventing direct contact and reduce friction between moving parts and hence reduce wear. In this short letter the lubrication of two slider bearings with parallel and nonparallel is studied. First, we show that bearings with parallel plates cannot support any load. For bearings with nonparallel plates we are interested on how constant and temperature dependent viscosity affects the properties of the bearings. Also, a critical temperature for which the bearings would fail due to excess in temperature is found for both latter cases. …

Aerodynamic Study Of Forces Due To Wind Velocity And Angle Of Attack On Parabolic Solar Troughs, Brian Northshield

Doctoral Dissertations and Master's Theses

Scant literature exists of the atmospheric effects on parabolic solar troughs. The technology is relatively new, so supporting studies by consequence are as well.

This study examines the effects of wind at various speeds, with various angles of attack on parabolic solar troughs. This begins by picking up on previous study, corroborating previously found data, then introduces new angles of attack. The model includes the presence of the solar tube where other studies omit.

The purpose of this study is to build a data set which is useful for structural consideration. During the course of this study, it was found …

Overview Of Instruments For Investigating Dust Interactions On Small Solar System Bodies By Landers And Rovers, Ryan L. Kobrick, Jeffrey A. Hoffman, Kenneth W. Street Jr., Douglas L. Rickman

Publications

Small Solar System bodies such as asteroids, comets and Mars' moons Phobos and Deimos have relatively unknown regolith environments. It is hypothesized that dust preserved in the regolith on the surfaces will have similar mechanical properties to lunar dust because of similar formation processes from micrometeoric bombardment, low relative gravity for slow settling times, and virtually no weathering because there is no atmosphere.

Early Damage State Criterion From A Fault-Seeded Helicopter Gear Using Acoustic Emission And Neural Networks, Rudy L. Baum

Doctoral Dissertations and Master's Theses

In response to five failures since 2008 of the tail gearbox of multiple models of Sikorsky's H-60 helicopter, acoustic emission (AE) data collected from a rotating gearbox test stand at the Naval Air Station in Patuxtent River, MD, was used to monitor the initiation and propagation of a flaw from an electro-discharge machined (EDM) notch seeded on the face of a gear tooth. A period of testing was considered which spanned ~300,000 seconds or ~83 hours and culminates to a damage state such that a flaw has initiated on both ends of the EDM notch. AE data was analyzed for …

Energy Conservation By Intermittently Recirculating And Aerating An Aquaponics System With An Airlift, Bjorg Magnea Olafs

Doctoral Dissertations and Master's Theses

An airlift device providing aeration and circulation was designed to reduce electrical power requirements for aquaponics by eliminating the need for a water pump. The airlift performed better than predicted and achieved water flow rates of 10 L/min at 25 °C, in comparison to the theoretical design performance 2.65 L/min.

Koi (Cyprinus carpio) and sweet basil (Ocimum basilicum) were cultured for five weeks in two identical aquaponics systems. The system was located indoors and consisted of a fish tank, a sump tank, and a soil-free growth media bed under artificial lighting. The total water volume in each system was 230 …

The Impact On Educational Technology Of A Fatal Airline Accident: A Case Study, Tim Brady

Publications

The name of the company should read Colgan Air not Cogan Airlines.

"This is a study of how a virtual technology burden was created that impacted the professional pilot college student and various colleges/universities that offer professional pilot degree programs. A cascading set of events began as a result of U.S. congressional reaction to a tragic airline accident. The resulting legislation forced the Federal Aviation Administration to publish new rules for first officer qualifications that were unmindful of the recommendations of professional pilot groups for simulation-based training. Ultimately, this placed a financial burden on both the college/university training curriculum and …

From The Editor-In-Chief, Ibrahim A. Baggili

Journal of Digital Forensics, Security and Law

We are proud to share with you this special edition issue of the JDFSL. This year, JDFSL partnered with both the 6th International Conference on Digital Forensics and Cyber Crime (ICDF2C) and Systematic Approaches to Digital Forensic Engineering (SADFE)–two prominent conferences in our field that were co-hosted. Fifty-three papers were submitted, and the Technical Program Committee accepted only 17 after a rigorous review process.

Space Shuttle Case Studies: Challenger And Columbia, Scott L. Post

Publications

The two Space Shuttle tragedies, Challenger and Columbia, have led to many papers on case studies on engineering ethics. The Challenger disaster in particular is often discussed due to the infamous teleconference that took place the night before the launch in which some engineers tried to postpone the launch. However, the space shuttle program itself is worthy of study as it relates to the engineering design process, and the details of the Challenger and Columbia disasters are worthy of discussion as they relate to a variety of sub-disciplines, including material science, thermodynamics, fluid mechanics, and heat transfer. This paper summarizes …

Assessing Customer Service In Airports – Models From The Uae, Aman Gupta, Mohammed Arif, Phillip A. Richardson

International Journal of Aviation, Aeronautics, and Aerospace

Customer service at airports has become a key priority for airport operators given the high degree of competitions. This paper uses an airport customer service model to analyze three examples from the United Arab Emirates (UAE). Passenger interviews, statistical information, customer feedback and other forms of information have been utilized to learn more about the customer view on the quality of service offered at these three airports. Detailed qualitative analysis of these case studies has highlighted some key issues in the area of customer service and identifies some opportunities for improvement.

An Analysis Of Airport Surface Deviations Using The Human Factors Analysis And Classification System (Hfacs), James H. Cistone

Doctoral Dissertations and Master's Theses

An analysis of accident and incident data from the Federal Aviation Administration Runway Safety database and the National Transportation Safety Board (NTSB) database was performed to determine causal factors for airport surface deviations over a 12-year period, from January 1, 2001 through December 31, 2012. The Human Factors Analysis and Classification System was used as the framework to analyze the NTSB data for causal factors.

Analysis of the NTSB data produced 289 airport surface deviation cases, which were analyzed for causal evidence, and the results indicated that skill-based errors occurred at least once in the largest frequency of airport surface …

A Comparative Study Of The Low Speed Performance Of Two Fixed Planforms Versus A Variable Geometry Planform For A Supersonic Business Jet, Aaron C. Smelsky

Doctoral Dissertations and Master's Theses

A numerical investigation of the effects of high lift devices on the low-speed performance of a generic swept wing and a delta wing was conducted. The two fixed planforms were initially sized to achieve the same high speed performance as the baseline variable geometry wing. Following a review of high lift devices a detailed analysis of their use was conducted with the aid of vortex lattice method and empirical formulations. The slat and Fowler flap combination proved to be the best mechanical solution. In comparison with the initially sized delta planform, the final delta planform required a 26% increase in …

Crew Resource Management And Its Possible Role In Nursing Risk Management, I. R. Mcandrew, G. P. Wise

Publications

Crew Resource Management (CRM) was introduced within the aviation industry in the late 1970s after an aircraft ran out of fuel whilst the pilots were trying to solve an undercarriage problem. To reduce such errors and ultimately lower the probability of failure and the severity of risks that occur, training in CRM was rolled out across the whole industry. It has been successful over the last few years in major reductions in the number of crashes and fatalities in the commercial aviation sector. Nursing has similar concerns in that errors can ultimately result in fatalities. There are parallels in the …