Engineering Commons^™

Nanoindentation And Plasticity In Nanocrystalline Ni Nanowires: A Case Study In Size Effect Mitigation, F. Sansoz, Virginie Rollin

Publications

We examine the processes of spherical indentation and tension in Ni nanowires and thin films containing random distributions of nanoscale grains by molecular dynamics simulations. It is shown that the resistance to nanoindentation of nanocrystalline Ni nanowires with diameters of 12 and 30 nm tends not to depend on the wire diameter and free surfaces, contrary to nanoindentation in single-crystalline nanowires. Accommodation of plastic deformation by grain boundary sliding suggests a mitigation strategy for sample boundary effects in nanoscale plasticity.

The U2 Spy Plane Crisis: Turning Point In The Cold War, William Weiss

ERAU Prescott Aviation History Program

When the Soviets shot down Francis Gary Powers’ U2 spy plane in 1960, it caused an international crisis. Thanks to recently declassified US and former Soviet archives, we can now hear the inside story of what really happened as told by an American History writer & lecturer.

Developing Proactive Methods For General Aviation Data Collection, Scott Shappell, Carla Hackworth, Kali Holcomb, John Lanicci, Massoud Bazargan, Jaclyn Baron, Rebecca Iden, Daniel Halperin

Publications

Introduction. Over the last 20 years, nearly 40,000 general aviation (GA) aircraft were involved in accidents, roughly 20% of which were fatal. To address this safety concern, scientists have often relied on accident data. Because of the rare nature of accidents, commercial aviation incident and near miss data may prove to be useful sources of safety information. In one such study, the National Transportation Safety Board interviewed GA pilots that were flying near a weather-related accident in pursuit of a different perspective than that of the accident pilot. Interviewing GA pilots about their own weather-related event may provide similar …

Defining An Abrasion Index For Lunar Surface Systems As A Function Of Dust Interaction Modes And Variable Concentration Zones, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street Jr.

Publications

Unexpected issues were encountered during the Apollo era of lunar exploration due to detrimental abrasion of materials upon exposure to the fine-grained, irregular shaped dust on the surface of the Moon. For critical design features involving contact with the lunar surface and for astronaut safety concerns, operational concepts and dust tolerance must be considered in the early phases of mission planning. To systematically define material selection criteria, dust interaction can be characterized by two-body or three-body abrasion testing, and sub-categorically by physical interactions of compression, rolling, sliding and bending representing specific applications within the system. Two-body abrasion occurs when a …

Numerical Simulation Of Marina Storage Fires Using Measured Composite Fire And Thermal Properties, Lulu Sun, Aixi Zhou, Andrew Valente

Publications

Fire test data of boats in rack storage are needed to establish more specific requirements for fire control and protection for this type of vessel in high piled rack storage configurations. Since there is no current large or full scale fire test data available, we have embarked upon testing fire and thermal properties of boat material, fiber reinforced polymer (FRP) composite, by using Differential Scanning Calorimetry, and Cone Calorimeter in order to determine the most effective method to provide sprinkler protection to an indoor boat storage facility. Fire and thermal properties of FRP were obtained from experiments and incorporated into …

Challenges To Informed Peer Review Matching Algorithms, Matthew Verleger, Heidi Diefes-Dux, Matthew W. Ohland, Mary Besterfield-Sacre, Sean Brophy

Publications

Background Peer review is a beneficial pedagogical tool. Despite the abundance of data instructors often have about their students, most peer review matching is by simple random assignment. In fall 2008, a study was conducted to investigate the impact of an informed algorithmic assignment method, called Un‐weighted Overall Need (UON), in a course involving Model‐Eliciting Activities (MEAs). The algorithm showed no statistically significant impact on the MEA Final Response scores. A study was then conducted to examine the assumptions underlying the algorithm.

Purpose (Hypothesis) This research addressed the question: To what extent do the assumptions used in making informed peer …

Deformation Waves In Microstructured Materials: Theory And Numerics, Juri Engelbrecht, Arkadi Berezovski, Mihhail Berezovski

Publications

A linear model of the microstructured continuum based on Mindlin theory is adopted which can be represented in the framework of the internal variable theory. Fully coupled systems of equations for macro-motion and microstructure evolution are represented in the form of conservation laws. A modification of wave propagation algorithm is used for numerical calculations. Results of direct numerical simulations of wave propagation in periodic medium are compared with similar results for the continuous media with the modelled microstructure. It is shown that the proper choice of material constants should be made to match the results obtained by both approaches

A Day In The Life Of A Float Plane Charter Pilot, Bryan Cox

ERAU Prescott Aviation History Program

Ever taken a float plane trip or wanted to? Learn what it’s like to be a float plane pilot doing charter work in the Puget Sound area of Washington state. Hear this light-heated, informal, presentation by someone who has done all this for “fun and profit”!

Body Limb Movement Limiter, Susan Davis Allen

Mechanical Engineering - Daytona Beach

A body limb movement limiter restrains the movement of a person's arm so as to protect the person's shoulder or restrains the movement of a person's lower leg with respect to the upper leg so as to protect the person's knee. The device uses a housing having a reel disposed therein with a tether attached thereto and a shear thickening non-Newtonian fluid disposed within the housing so that the fluid acts on the reel during a payout procedure of the tether. The housing is attached to a strap secured about the torso of the person while the free end of …

Dynamic Solidification In Nanoconfined Water Films, Peter M. Hoffmann, Shah H. Khan, George Matei, Shivprasad Patil

Publications

Mechanical properties of nanoconfined water layers are still poorly understood and continue to create controversy, despite their importance for biology and nanotechnology. We report on dynamic nanomechanical measurements of water films compressed to a few single molecular layers. We show that the mechanical properties of nanoconfined water layers change significantly with their dynamic state. In particular, we observed a sharp transition from viscous to elastic response even at extremely slow compression rates, indicating that mechanical relaxation times increase dramatically once water is compressed to less than 3–4 molecular layers.

Multi-Color Cavity Ringdown Based Detection Method And Apparatus, Scott Reeve, Susan Allen

Mechanical Engineering - Daytona Beach

A multi-color cavity ringdown based spectrometer is housed in a light tight enclosure to detect the presence of trace quantities of gas phase molecules emanating from explosives, drugs, or hazardous materials being transported through the enclosure or compounds contained in a patient's breath. A method is also disclosed for detecting gas phase molecules emanating from explosives, drugs, hazardous materials, or a patient's breath.

Three-Body Abrasion Testing Using Lunar Dust Simulants To Evaluate Surface System Materials, Ryan L. Kobrick, Kenneth G. Budinski, Kenneth W. Street Jr., David M. Klaus

Publications

Numerous unexpected operational issues relating to the abrasive nature of lunar dust, such as scratched visors and spacesuit pressure seal leaks, were encountered during the Apollo missions. To avoid reoccurrence of these unexpected detrimental equipment problems on future missions to the Moon, a series of two- and three-body abrasion tests were developed and conducted in order to begin rigorously characterizing the effect of lunar dust abrasiveness on candidate surface system materials. Two-body scratch tests were initially performed to examine fundamental interactions of a single particle on a flat surface. These simple and robust tests were used to establish standardized measurement …

Elements Of Study On Dynamic Materials, Marine Rousseau, Gerard A. Maugin, Mihhail Berezovski

Publications

As a preliminary study to more complex situations of interest in small-scale technology, this paper envisages the elementary propagation properties of elastic waves in one-spatial dimension when some of the properties (mass density, elasticity) may vary suddenly in space or in time, the second case being of course more original. Combination of the two may be of even greater interest. Toward this goal, a critical examination of what happens to solutions at the crossing of pure space-like and time-like material discontinuities is given together with simple solutions for smooth transitions and numerical simulations in the discontinuous case. The effects on …

Will Very Light Jets Replace King Air Turboprops For Business Travel?, Vince Jean-Paul Pujalte

Applied Aviation Sciences - Prescott

The purpose of this research was to determine if Very Light Jets (VLJs) such as the Eclipse 500 might replace the Beechcraft King Air Turboprop as the preferred aircraft for short regional flights. There are often significant distances from the location of a given company to the nearest customer. Traveling these distances requires travel time, significant funding, and inconvenience. The research method utilized developed and distributed a survey to present owners of Beechcraft King Air Turboprops used for regional business travel. After careful analysis of the data, the researcher concluded that the present owners of King Air Turboprops were very …

Scan Loss Pattern Synthesis For Adaptive Array Ground Stations, William C. Barott, Mary Ann Ingram, Paul G. Steffes

Publications

We present several techniques for maximizing the contact time between low Earth orbiting satellites (LEOs) and a ground station (GS). The GS comprises an adaptive array of electronically steered space-fed lenses (SFLs). Each SFL is manufactured as a low-cost printed circuit with the result that it exhibits scanning loss. By differently orienting the boresights of the SFLs in the adaptive array, the SFL's scanning losses can be made to optimally complement the path loss of the LEO, thereby reducing the cost of the GS while maximizing the download capacity of the satellite link. The optimization, implemented with a genetic algorithm …

A Design-Build-Test-Fly Project Involving Modeling, Manufacturing, And Testing, Scott Post, Shankar Seetharaman, Sree Abimannan

Publications

This paper describes a junior-level semester-long class project for students in Fluid Mechanics courses. The goals of the project are to introduce students to engineering design, project management, and to incorporate material from other courses in engineering graphics, numerical methods, instrumentation and measurements, and manufacturing processes in a single project. The project focuses on airfoil design using computational tools, and the main emphasis lies on verification of results obtained from computational methods with experimentally measured values. Students will use the airfoil shape they select to make wings to go on a model foam glider. The final part of the project …

Effect Of Simulated Visual Impairment On Nighttime Driving Performance, Joanne Wood, Alex Chaparro, Trent Carberry, Byoung Sun Chu

Publications

Purpose. This study investigated the effects of simulated visual impairment on nighttime driving performance and pedestrian recognition under real-road conditions.

Methods. Closed road nighttime driving performance was measured for 20 young visually normal participants (M = 27.5 +- 6.1 years) under three visual conditions: normal vision, simulated cataracts, and refractive blur that were incorporated in modified goggles. The visual acuity levels for the cataract and blur conditions were matched for each participant. Driving measures included sign recognition, avoidance of low contrast road hazards, time to complete the course, and lane keeping. Pedestrian recognition was measured for pedestrians wearing either black …

Standardization Of A Volumetric Displacement Measurement For Two-Body Abrasion Scratch Test Data Analysis, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street Jr.

Publications

A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume displacement metrics are systematically defined by normalizing the overall surface profile to statistically denote the area of relevance, termed the “Zone of Interaction” (ZOI). From this baseline, depth of the trough and height of the …

A Proposed Learner-Centered Mechatronics Engineering Instructional Program, Patrick N. Currier, Richard Goff, Janis Terpenny

Mechanical Engineering - Daytona Beach

This paper examines the need and requirements for a mechatronics degree program. The results of a survey of the few existing programs in this field are provided. Then, using a case study example for Virginia Tech, a proposed mechatronics curriculum based on a learner-centered paradigm is described. The curriculum combines existing courses in mechanical, electrical, and computer engineering with new, hands-on courses to provide students with a chance to practice and explore the subject matter in ways consistent with the demands of both industry and accreditation. This program, if implemented, could provide a university with a unique offering to attract …

Stability Of Fully Nonlinear Stokes Waves On Deep Water: Part 1. Perturbation Theory, Shahrdad Sajjadi, David L. Ross

Publications

We consider a full set of harmonics for the Stokes wave in deep water in the absence of viscosity, and examine the role that higher harmonics play in modifying the classical Benjamin-Feir instability. Using a representation of the wave coefficients due to Wilton, a perturbation analysis shows that the Stokes wave may become unbounded due to interactions between the N^th harmonic of the primary wave train and a set of harmonics of a disturbance. If the frequency of the n^th harmonic is denoted Ꙍ_n = Ꙍ(1 ± ꭉ) then instability will occur if

√2 k n^{n …}

A Historical Look At The Av-8 Harrier Program, Bill O'Hara

ERAU Prescott Aviation History Program

Hear the inside story of one of the most controversial airplanes ever introduced to Naval Aviation, as told by a Marine pilot with more than 3,000 hours in the Harrier. Bill (Prof) O’Hara, was also the real pilot in the movie “True Lies” with Arnold Schwarzenegger!

The New Aviation Meteorology Specialization In The Graduate Aeronautics Program At Embry-Riddle, John M. Lanicci, Erin A. Roberts

School of Graduate Studies - Daytona Beach

The next 12 months will be an exciting time of growth in graduate aviation studies at Embry-Riddle Aeronautical University's Daytona Beach, FL campus. Beginning in Fall Semester 2009, a new Area of Concentration (AOC) in Aviation Meteorology will be added to the Master of Science in Aeronautics (MSA) program, and the new Doctoral program in Aviation will be starting in January 2010. The Aviation Meteorology AOC adds a crucial specialty to the existing MSA options in Air Traffic Management, Aviation/Aerospace Education Technology, Aviation/Aerospace Management, Aviation/Aerospace Operations, and Aviation/Aerospace Safety Systems.

The Aviation Meteorology AOC is designed to be a cross-disciplinary …

Pilot Source Study: An Analysis Of Pilot Backgrounds And Subsequent Success In Us Regional Airline Training Programs, Guy M. Smith, David A. Newmyer, Elizabeth Bjerke, Mary Niemczyk, Raymond A. Hamilton

Applied Aviation Sciences - Daytona Beach

The 2010 Pilot Source Study, commissioned to research the success of pilots in initial training for Part 121 operations, analyzed the training performance of 2,156 new-hire pilots in the years 2005-2009. Six regional airlines provided data that was mined from human resource and pilot training files. Five university researchers independently analyzed the data and integrated their results. The study expressed success in terms of fewer extra training events and fewer non-completions in regional airline training. Statistically, the best performing pilots were those who had flight instructor certificates, graduated from collegiate accredited flight programs, received advanced (post-Private) pilot training in college, …

Waves In Materials With Microstructure: Numerical Simulation, Mihhail Berezovski, Arkadi Berezovski, Juri Engelbrecht

Publications

Results of numerical experiments are presented in order to compare direct numerical calculations of wave propagation in a laminate with prescribed properties and corresponding results obtained for an effective medium with the microstructure modelling. These numerical experiments allowed us to analyse the advantages and weaknesses of the microstructure model.

Temporal Scales For Transport Patterns In The Gulf Of Finland, Bert Viikmae, Tarmo Soomere, Mikk Viidebaum, Mihhail Berezovski

Publications

The basic time scales for current-induced net transport of surface water and associated time scales of reaching the nearshore in the Gulf of Finland, the Baltic Sea, are analysed based on Lagrangian trajectories of water particles reconstructed from three-dimensional velocity fields by the Rossby Centre circulation model for 1987–1991. The number of particles reaching the nearshore exhibits substantial temporal variability whereas the rate of leaving the gulf is almost steady. It is recommended to use an about 3 grid cells wide nearshore area as a substitute to the coastal zone and about 10–15 day long trajectories for calculations of the …

Graduate Curricula In Software Engineering And Software Assurance: Need And Recommendations, T. B. Hilburn, Andrew J. Kornecki

Department of Electrical Engineering and Computer Science - Daytona Beach

In discussions about the development and use of computer systems and software products, the term “professional software engineer” is used repeatedly. In the last two decades there has been significant effort devoted to enhancing and advancing the state of professional software engineering (SwE) – new software engineering processes, methods, tools, and practices; creation of a software engineering body of knowledge [1]; development of a code of ethics and professional conduct [2], and software certification and licensing programs [3] . In 1989 the Software Engineering Institute (SEI) of Carnegie Mellon University published a landmark report on graduate education in software engineering …

Hardware Certification For Real-Time Safety-Critical Systems: State Of The Art, Andrew J. Kornecki, Janusz Zalewski

Department of Electrical Engineering and Computer Science - Daytona Beach

This paper discusses issues related to the RTCA document DO-254 Design Assurance Guidance for Airborne Electronic Hardware and its consequences for hardware certification. In particular, problems related to circuits’ compliance with DO-254 in avionics and other industries are considered. Extensive literature review of the subject is given, including current views on and experiences of chip manufacturers and EDA industry with qualification of hardware design tools, including formal approaches to hardware verification. Some results of the authors’ own study on tool qualification are presented.