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Digital Communications and Networks 2024年第2期10卷 282-291页

作者： Jiachen Yang Meng Xi Jiabao Wen Yang Li Houbing Herbert Song School of Electrical and Information Engineering Tianjin UniversityTianjin300072China Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA

The Autonomous Underwater Glider(AUG)is a kind of prevailing underwater intelligent internet vehicle and occupies a dominant position in industrial applications,in which path planning is an essential *** to the complexity and variability of the ocean,accurate environment modeling and flexible path planning algorithms are pivotal *** traditional models mainly utilize mathematical functions,which are not complete and *** existing path planning algorithms depend on the environment and lack *** overcome these challenges,we propose a path planning system for underwater intelligent internet *** applies digital twins and sensor data to map the real ocean environment to a virtual digital space,which provides a comprehensive and reliable environment for path *** design a value-based reinforcement learning path planning algorithm and explore the optimal network structure *** path simulation is controlled by a closed-loop model integrated into the terminal vehicle through edge *** integration of state input enriches the learning of neural networks and helps to improve generalization and *** task-related reward function promotes the rapid convergence of the *** experimental results prove that our reinforcement learning based path planning algorithm has great flexibility and can effectively adapt to a variety of different ocean conditions.

关键词： Digital twins Reinforcement learning Edge computing Underwater intelligent internet vehicle Path planning

Effect of Spray Rails on Takeoff Performance of Amphibian Aircraft

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World Journal of Engineering and Technology 2024年第1期12卷 117-140页

作者： Soham S. Bahulekar Alberto W. Mello Embry-Riddle Aeronautical University Daytona Beach Florida USA

Amphibian aircraft have seen a rise in popularity in the recreational and utility sectors due to their ability to take off and land on both land and water, thus serving a myriad of purposes, such as aerobatics, surveillance, and firefighting. Such seaplanes must be aerodynamically and hydrodynamically efficient, particularly during the takeoff phase. Naval architects have long employed innovative techniques to optimize the performance of marine vessels, including incorporating spray rails on hulls. This research paper is dedicated to a comprehensive investigation into the potential utilization of spray rails to enhance the takeoff performance of amphibian aircraft. Several spray rail configurations obtained from naval research were simulated on a bare Seamax M22 amphibian hull to observe an approximate 10% - 25% decrease in water resistance at high speeds alongside a 3% reduction in the takeoff time. This study serves as a motivation to improve the design of the reference airplane hull and a platform for detailed investigations in the future to improve modern amphibian design.

关键词： Seaplane Spray Rails Hull Optimization Take-Off Performance

Impact of COVID-19 on Safety Performance for Motorcycles: Pre-and during-Pandemic Conditions

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Journal of Transportation Technologies 2024年第3期14卷 390-401页

作者： Hongyun Chen Amelia Lawson Charles Hurda Madalyn Smith Tate Grant Civil Engineering Department Embry-Riddle Aeronautical University Daytona Beach FL USA

Florida has the highest number of motorcycle fatalities in the United States and contains the second largest population of registered motorcycles. The COVID-19 pandemic influenced the roads, traffic, and driving behavior in the continental United States. Motorcycle crashes decreased during the COVID-19 years (2020 and 2021) while the fatality rates increased. The purpose of this study is to 1) investigate motorcycle crashes before and during the Pandemic period to understand the impacts on motorcycle safety and contributing factors to the crash severity levels;2) develop the crash predictive model for different degrees of severity in motorcycle crashes in Florida. Florida statewide crash data were collected. T tests have been conducted to compare the contributing factors between two periods. The injury severities are significantly different among all five levels between those during normal period and the Pandemic period. A crash predictive model has been developed to determine the facts to injury severity levels for motorcycle crashes. A total of eight variables are found to significantly increase the injury severity levels for motorcycle crashes during the Pandemic period.

关键词： Motorcycle Crash Pandemic Injury Severity Contributing Factors

Hazardous Attitude Factors Influence Risk Perception in General Aviation Pilots

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Advances in Aerospace Science and Technology 2024年第3期9卷 85-93页

作者： Athina Holmes Aeronautical Science Department College of Aviation Embry-Riddle Aeronautical University Daytona Beach FL USA

This manuscript presents a research proposal to investigate how hazardous attitudes among general aviation pilots influence pilot performance in aviation accidents. General aviation pilots train to maintain safe flying conditions, but accidents still occur, and human factors figure prominently among the causes of aviation accidents. The levels of hazardous attitudes among pilots may influence the likelihood of engaging in risky flight behaviors that can lead to accidents. This quantitative study aims to determine whether dangerous attitudes impact risk perception in general aviation pilots. The study will focus on two specific hazardous attitudes, “Anti-Authority” and Macho” behaviors. Among the hazardous attitudes identified by the Federal Aviation Administration (FAA), the two attitudes often stand out in accident investigations and pilot narratives. While all hazardous attitudes have inherent dangers, these two attitudes tend to be more frequently cited in accident reports and investigations. Despite rigorous training in safe flying conditions, general aviation accidents still transpire due to human factors. This research hypothesizes that the five attitudes from the hazardous attitude model, particularly Anti-Authority and Macho, significantly shape pilots’ risk perception. The insights from this study would benefit stakeholders, like the Aircraft Owners and Pilots Association (AOPA), Air Safety Institute, and aviation training programs, in creating training modules tailored to reduce such attitudes.

关键词： General Aviation (GA) Pilot Aviation Safety Hazardous Attitudes Anti-Authority Macho Risk Perception Flight Training

Assessment of conventional and air-jet wheel deflectors for drag reduction of the DrivAer model

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Advances in Aerodynamics 2021年第1期3卷 512-539页

作者： Kaloki L.Nabutola Sandra K.S.Boetcher Department of Mechanical Engineering Embry-Riddle Aeronautical UniversityDaytona BeachFLUSA

Aerodynamic drag is a large resistance force to vehicle motion,particularly at highway *** wheel deflectors were designed to reduce the wheel drag and,consequently,the overall vehicle drag;however,they may actually be detrimental to vehicle aerodynamics in modern *** the present study,computational fluid dynamics simulations were conducted on the notchback DrivAer model-a simplified,yet realistic,open-source vehicle model that incorporates features of a modern passenger *** and air-jet wheel deflectors upstream of the front wheels were introduced to assess the effect of underbody-flow deflection on the vehicle *** wheel-deflector designs with varying heights were observed and compared to 45◦and 90◦air-jet wheel *** conventional wheel deflectors reduced wheel drag but resulted in an overall drag increase of up to 10%.For the cases studied,the 90◦air jet did not reduce the overall drag compared to the baseline case;the 45◦air jet presented drag benefits of up to 1.5%at 35 m/s and *** to conventional wheel deflectors,air-jet wheel deflectors have the potential to reduce vehicle drag to a greater extent and present the benefit of being turned off at lower speeds when flow deflection is undesirable,thus improving efficiency and reducing emissions.

关键词： Vehicle aerodynamics Wheel and wheelhouse aerodynamics Automotive Active flow control Passive flow control DrivAer

A modeling and simulation framework for UAVs utilizing 4G-LTE cellular networks

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第5期9卷 108-139页

作者： Shafagh Jafer Stephen Jones Ashok Vardhan Raja Department of Electrical ComputerSoftwareand Systems Engineering Embry-Riddle Aeronautical UniversityDaytona Beach32114 FLUSA

Only a small amount of work has been published on the topic of exploiting existing Long-Term Evolution-Advanced(LTE)cellular communication network infrastructure for Unmanned Aerial Vehicles(UAV)data *** paper documents a modeling and simulation(m&s)framework that has been developed utilizing the powerful OMNeT++simulation tool for assessing the feasibility and effectiveness of this prospect in various UAV *** multiple scenarios,we have studied the data rate requirements for communications between small and medium-sized UAVs and base *** this framework,we have shown that the data rate requirements for the links are within the data throughput achieved by LTE *** developed framework implements a propagation model endorsed by the 3GPP LTE project team and also accurately models the high mobility of *** framework is highly configurable and extensible and boasts of automatic aggregation of results and chart *** outcomes of this research may be utilized by industry for rapidly deploying highly mobile,low-cost UAVs in a wide range of applications and scenarios.

关键词： Unmanned air vehicle communication UAV Data Link OMNET++ 4GLTE modeling and simulation.

The Effect of Pre-Thermal and -Load Conditions on IN-718 High Temperature Fatigue Life

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Open Journal of Applied Sciences 2022年第3期12卷 406-419页

作者： Paulina E. De La Torre Alberto W. Mello Embry-Riddle Aeronautical University Daytona Beach USA

Ni-based superalloys are largely used in the aerospace industry as critical components for turbine engines due to their excellent mechanical properties and fatigue resistance at high temperatures. A hypothesis to explain this atypical characteristic among metals is the presence of a cross-slip mechanism. Previous work on the role of thermal activation on cubic slip has shown strain accommodation in two sets of slip planes, which resembled the activation of {100} cubic slip systems along of the octahedral slip planes {111} in Ni-based superalloys under high strain and temperature, exhibiting a more homogeneous strain distribution and less strain localization. Following those previous literature evaluations of initial conditions that can potentially activate cubic-slip planes and provide the level of accommodation and strain homogenization within the grain, this paper presents some experimental procedures and results of Ni-based superalloy (IN-718) tested at 500°C under operational loading condition, without and after being submitted to an overload and overtemperature. The experiments have shown that a pre-condition of 1% strain at 700°C would increase the fatigue life of the IN-718 at 500°C by four times when compared to pristine tested samples. The present results bring up the potential of improving this material fatigue performance, opening the need to further investigate the microstructure as the precondition is applied.

关键词： Metal Fatigue Ni-Based Superalloys Cube Slip Microstructure High Temperature

Dual-System Activation of Ni-Base Superalloy under High Strain and High Temperature

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Open Journal of Applied Sciences 2023年第12期13卷 2320-2328页

作者： Alexandru Lopazan Alberto W. Mello Embry-Riddle Aeronautical University Daytona Beach FL USA

Due to their superior combination of heat resistance, high temperature corrosion resistance, toughness and strength, nickel-based superalloys have become of extensive use in the aerospace industry. This research aims to explain why the fatigue life of Inconel-718 in preconditioned samples had larger fatigue lives than pristine samples. The hypothesis is that preconditioning at 700°C and 1.0% strain could lead to thermal activation of the {100} cubic slip plane alongside the {111} octahedral slip plane, potentially improving fatigue life. Using SEM and EBSD imaging, the microstructure of Inconel-718 samples were characterized before and after preconditioning. The directions of the slip bands that formed following the preconditioning were determined. The result was that the existence of both the cubic and octahedral slip systems was confirmed, leading to the thermal activation hypothesized. The existence of both slip planes was considered to be the reason behind the improved fatigue life due to better strain accommodation within the microstructure. It is suggested that focuses for future research includes conducting in-situ observation of slip activation and the application of preconditioning as a manufacturing method.

关键词： Metal Fatigue Ni-Based Superalloys Cube Slip Microstructure High Temperature

Airport Information Systems—Airside Management Information Systems

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Intelligent Information Management 2014年第3期6卷 149-156页

作者： Adam Marks Kees Rietsema College of Business Embry-Riddle Aeronautical University Worldwide Daytona Beach USA

Research on the intersection of the areas of aviation and management of information systems is scarce. Airports, more than ever before need to align their information systems to gain a competitive advantage and become more efficient in their operations. A proper classification is a prerequisite to systems alignment. The purpose of this paper is to provide descriptions of some of the airport management information systems, connections to or interoperability with other systems, and the key uses and users of each system. There are many types of management information systems and they can be organized or classified in a number of different ways. Furthermore, each system may or may not be necessary for a particular airport depending on the business goals and objectives and the certificate which the airport is operating under. Consequently, the system classification schema presented in this paper is neither all-inclusive nor exclusive;however, a number of leading aviation practitioners, business professionals, and educators in the industry were instrumental in both proposing and validating the schema. The study used interviews, documentation, and observation as the primary sources of data.

关键词： Airport Aviation Management Information Systems Airside

Vacuum Preparation, Optimization of Cylinder Length and Postoperative Daily Inflation Reduces Complaints of Shortened Penile Length Following Implantation of Inflatable Penile Prosthesis

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Advances in Sexual Medicine 2013年第1期3卷 14-18页

作者： Tom Sellers Martin Dineen Emad A. Salem Steven K. Wilson daytona beach USA Indio CA USA Zagazig University Zagazig Egypt

Introduction: The inflatable penile prosthesis (IPP) has been used to treat erectile dysfunction for 40 years. Loss of penile length following IPP remains the single biggest patient complaint. We describe a preoperative and postoperative patient preparation protocol to assist in setting realistic patient expectations and decreasing the complaint of reduced penile length. Materials & Methods: 750 Patients are instructed to use a vacuum erection device for 10 minutes each day for up to 2 months prior to IPP implant. After two months, maximization of cylinder length is accomplished regardless of IPP manufacturer. Cylinders are left partially inflated in the post-operative period and daily inflation for 3 months immediately upon patient tolerance. The average implanted cylinder length has increased dramatically with the preoperative vacuum usage when compared to the authors’ previous implantations and when compared to the national average of implanted cylinders obtained from one manufacturer. Results: Preoperative use of the vacuum device has allowed maximization of cylinder length. After the vacuum program, patients tend to experience less pain following implantation allowing earlier device instruction cycling and use. The average implanted cylinder length continued to increase annually for the first 5 years as the protocol evolved and seems to have remained stable for the last five years. Conclusions: Preoperative vacuum usage and postoperative capsule management has nearly eliminated patient complaints of reduced penile length. We believe this to be the result of larger size cylinders being implanted when compared to our previous implantations absent of the patient participation protocol.

关键词： Inflatable Penile Prosthesis Vacuum Device Satisfaction