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Full-Text Articles in Engineering

2019 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick May 2019

2019 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick

PRC Graduate Recognition

This program includes the graduate recognition program for spring 2019. Includes photographs, upcoming events, recent publications, and student profiles.


Community Discovery In Heterogeneous Social Networks, Lei Meng, Ah-Hwee Tan, Donald C. Wunsch May 2019

Community Discovery In Heterogeneous Social Networks, Lei Meng, Ah-Hwee Tan, Donald C. Wunsch

Research Collection School Of Computing and Information Systems

Discovering social communities of web users through clustering analysis of heterogeneous link associations has drawn much attention. However, existing approaches typically require the number of clusters a priori, do not address the weighting problem for fusing heterogeneous types of links, and have a heavy computational cost. This chapter studies the commonly used social links of users and explores the feasibility of the proposed heterogeneous data co-clustering algorithm GHF-ART, as introduced in Sect. 3.6, for discovering user communities in social networks. Contrary to the existing algorithms proposed for this task, GHF-ART performs real-time matching of patterns and one-pass learning, which guarantees …


Towards Personalized Data-Driven Bundle Design With Qos Constraint, Mustafa Misir, Hoong Chuin Lau May 2019

Towards Personalized Data-Driven Bundle Design With Qos Constraint, Mustafa Misir, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In this paper, we study the bundle design problem for offering personalized bundles of services using historical consumer redemption data. The problem studied here is for an operator managing multiple service providers, each responsible for an attraction, in a leisure park. Given the specific structure of interactions between service providers, consumers and the operator, a bundle of services is beneficial for the operator when the bundle is underutilized by service consumers. Such revenue structure is commonly seen in the cable television and leisure industries, creating strong incentives for the operator to design bundles containing lots of not-so-popular services. However, as …


Re-Org: An Online Repositioning Guidance Agent, Muralidhar Konda, Pradeep Varakantham, Aayush Saxena, Meghna Lowalekar May 2019

Re-Org: An Online Repositioning Guidance Agent, Muralidhar Konda, Pradeep Varakantham, Aayush Saxena, Meghna Lowalekar

Research Collection School Of Computing and Information Systems

No abstract provided.


Designated-Server Identity-Based Authenticated Encryption With Keyword Search For Encrypted Emails, Hongbo Li, Qiong Huang, Jian Shen, Guomin Yang, Willy Susilo May 2019

Designated-Server Identity-Based Authenticated Encryption With Keyword Search For Encrypted Emails, Hongbo Li, Qiong Huang, Jian Shen, Guomin Yang, Willy Susilo

Research Collection School Of Computing and Information Systems

In encrypted email system, how to search over encrypted cloud emails without decryption is an important and practical problem. Public key encryption with keyword search (PEKS) is an efficient solution to it. However, PEKS suffers from the complex key management problem in the public key infrastructure. Its variant in the identity-based setting addresses the drawback, however, almost all the schemes does not resist against offline keyword guessing attacks (KGA) by inside adversaries. In this work we introduce the notion of designated-server identity-based authenticated encryption with keyword search (dIBAEKS), in which the email sender authenticates the message while encrypting so that …


Unmanned Aerial System Integration Into The National Airspace System And Airports: Risk Mitigation Using Content Analysis Methodology, Bhoomin Bhupendrabhai Chauhan May 2019

Unmanned Aerial System Integration Into The National Airspace System And Airports: Risk Mitigation Using Content Analysis Methodology, Bhoomin Bhupendrabhai Chauhan

Theses and Dissertations

Over the last few years, the use of unmanned aerial systems (UAS) has significantly increased. With an increase in the use of UASs, the number of UAS sightings near manned aircraft and airports have also increased, as shown by the Federal Aviation Administration (FAA)(FAA, 2019a). Although not every near sighting had a severe consequence associated with it, the risks were still present. As UASs are becoming more readily available to the general public, the risks present due to UASs flying in the National Airspace System (NAS) and near airports is also increasing. For the study, incident and accident reports were …


Factors Related To The Assessment Of The Effectiveness Of Environmental Management Systems (Ems) At Airports, Kainan Li May 2019

Factors Related To The Assessment Of The Effectiveness Of Environmental Management Systems (Ems) At Airports, Kainan Li

Theses and Dissertations

The purpose of this study was to identify factors that can be used to assess the effectiveness of EMS at airports in the United States (U.S.). A survey research methodology was used for this study in two phases. The first phase of the research study included a preliminary expert opinion survey of airport managers and other individuals acting in a supervisory role to determine and discuss how EMS help improve environmental performance, and ranked factors that may be related to assessing the effectiveness of EMS. The second survey was constructed based on feedback from these experts and targeted airport employees …


Aviation Professionalism: Examining The Concept Of Professionalism Within And Between Major Subgroups Of The Aviation Industry, Rüştü Tolga Turgut May 2019

Aviation Professionalism: Examining The Concept Of Professionalism Within And Between Major Subgroups Of The Aviation Industry, Rüştü Tolga Turgut

Theses and Dissertations

The purpose of this study was to conduct a secondary analysis of Alhallaf’s (2016) study on aviation professionalism by disaggregating his data into five subgroups: Aircraft Maintenance Technicians (AMT); Airport Managers (AM); Air Traffic Controllers (ATC); Non-Pilot Aviation Employees (NPAE), which consisted of business aviation, flight operations, and aviation colleges/universities; and Pilots. The study posed three research questions and endeavored to (a) determine factors related to professionalism in each subgroup, (b) determine the differences in levels of professionalism among the subgroups, and (c) examine each subgroup’ perceptions of professionalism. The study used an explanatory correlational design to determine the relationship …


Mitigating Risk Tolerance Among General Aviation Pilots: Identifying Factors That Contribute To Ga Pilots’ Risk Perception, Nazif Sani Nuhu May 2019

Mitigating Risk Tolerance Among General Aviation Pilots: Identifying Factors That Contribute To Ga Pilots’ Risk Perception, Nazif Sani Nuhu

Theses and Dissertations

The purpose of this study was to identify factors that contributed to general aviation (GA) pilots’ level of risk perception, which could then be manifested as an increase in risk tolerance. The study used an explanatory correlational design to determine what factors were related to risk perception. Research factors included gender, age, marital status, race/ethnicity, education level, flight hours, single- and multi-engine hours, hours as PIC, type of flight training, number of FAA licenses/ratings, number of hazardous events pilots were involved in, self-efficacy, aviation safety attitudes, level of psychological distress, and locus of control. The dependent variable was risk perception. …


Study Of A Crew Transfer Vehicle Using Aerocapture For Cycler Based Exploration Of Mars, Larissa Balestrero Machado May 2019

Study Of A Crew Transfer Vehicle Using Aerocapture For Cycler Based Exploration Of Mars, Larissa Balestrero Machado

Theses and Dissertations

This thesis presents the results of a conceptual design and aerocapture analysis for a Crew Transfer Vehicle (CTV) designed to carry humans between Earth or Mars and a spacecraft on an Earth-Mars cycler trajectory. The thesis outlines a parametric design model for the Crew Transfer Vehicle and presents concepts for the integration of aerocapture maneuvers within a sustainable cycler architecture. The parametric design study is focused on reducing propellant demand and thus the overall mass of the system and cost of the mission. This is accomplished by using a combination of propulsive and aerodynamic braking for insertion into a low …


A First-Principle Power And Energy Model For Evtol Vehicles, Max Skuhersky May 2019

A First-Principle Power And Energy Model For Evtol Vehicles, Max Skuhersky

Theses and Dissertations

A number of well-established aircraft manufacturers, such as Airbus, Boeing, or Bell, along with new startups have begun developing flying prototypes of electric Vertical Takeoff and Landing vehicles (eVTOL). To certify this emerging type of air mobility vehicles for commercial use, the Federal Aviation Administration (FAA) is considering adjusting currently used certification procedures for small aircraft to include eVTOL vehicles. One of the hurdles to this approach is that eVTOL vehicles are neither able to glide like a small, fixed-wing aircraft, nor to autorotate, like a helicopter, if the batteries are depleted. Therefore, active energy management and energy awareness by …


Validation Of An External Bioreactor Filtration Loop Prototype For A Tissue Engineering Test Bed, Jonah Martin Melegrito May 2019

Validation Of An External Bioreactor Filtration Loop Prototype For A Tissue Engineering Test Bed, Jonah Martin Melegrito

Theses and Dissertations

As a cell line thrives within a culture, some of the cells undergo the natural process of death. Whether it is due to apoptotic or necrotic causes, cell death is a significant hurdle for tissue engineering and cell cultivation. When cells attached to a scaffold die, they slough off from the scaffold into the bloodstream. If left unchecked, these dead cells and any cellular waste products accumulate and could affect the living cells’ ability to survive. The objective of this thesis was to construct a separation system that can filter away any unwanted suspended solids while allowing nutrients to recycle …


Residence Time Distribution (Rtd) Analysis Of A Bioreactor's External Recirculation Loop For A Tissue Engineering Test Bed, Adrien Hosking May 2019

Residence Time Distribution (Rtd) Analysis Of A Bioreactor's External Recirculation Loop For A Tissue Engineering Test Bed, Adrien Hosking

Theses and Dissertations

Currently, in tissue engineering, the focus is on morphing cells into a particular type of tissue by hand, rather than automating the process. Automating cell feeding and waste removal, alone, still requires the removal of cells from their culture to perform imaging and analysis. Without the ability to automate the imaging in a way that does not risk cell death, the advantages of automating the feeding and waste removal are largely lost. By building a fully automated tissue engineering test bed, the capacity for cell reproducibility and cell yield increases significantly. This thesis outlines the design, some initial testing, and …


Hrv - Ecg Generator: Software For Testing Heart Rate Variability Detection, Matthew Joseph Pogorelec May 2019

Hrv - Ecg Generator: Software For Testing Heart Rate Variability Detection, Matthew Joseph Pogorelec

Theses and Dissertations

Heart rate variability (HRV) has been shown to serve as an effective diagnostic and prognostic tool in a variety of clinical applications, including for patients who have suffered from myocardial infarction, sepsis and liver cirrhosis. There currently exist a variety of devices and software to quantify HRV based on RR interval series collected from ECG data. However, as the uses for HRV expand, a greater variety of devices for different applications are being designed and developed. Thus, it is useful to have available a method for efficiently testing preliminary software. The HRV/ECG Generator software is designed to build both an …


Geo-Locating Ues Using Multi-Output Decision Tree Regressor, Edel Goreil Dawood May 2019

Geo-Locating Ues Using Multi-Output Decision Tree Regressor, Edel Goreil Dawood

Theses and Dissertations

Mobile communication networks constantly need to monitor and improve the quality of service and network coverage to their users, and to do so, radio measurements are required. One common method for gathering these measurements is Drive Tests (DT) in which vehicles equipped with measuring devices are sent to locations of interests. However, DT has several limitations one of which is that DT cannot be performed on indoor locations. Other approaches were later used; however, failed to prove a considerably higher efficiency. To address this need, mobile operators developed a standardized technique called Minimization of Drive Test (MDT) that take advantage …


Hybrid Long-Range Mid-Infrared Hyperbolic Phonon Polariton Waveguide Using Hexagonal Boron Nitride, Di Xiong May 2019

Hybrid Long-Range Mid-Infrared Hyperbolic Phonon Polariton Waveguide Using Hexagonal Boron Nitride, Di Xiong

Theses and Dissertations

For any photonic-on-chip applications long propagation waveguides are critical. The use of plasmon polaritons for near-infrared and optical networks has been extensively studied for the purpose of achieving long propagation lengths, however, due to plasmonic polariton effects being negligible in mid- to long-wave infrared (IR) applications, phonon polaritons are required. In recent years, extensive research has been carried out on hexagonal boron nitride (h-BN), and it has been found that h-BN has naturally occurring sub-range phonon volume-constrained hyperbolic phonon polaritons (HPhPs). The numerical results in this thesis show both the long-range and short-range phonon volume polaritons modes in h-BN. A …


Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov May 2019

Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov

Theses and Dissertations

The thesis analyzes a flight software of a new free flying robot Astrobee, that will change the current Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) on International Space Station (ISS). First, the main components of the flight software were examined: Robotic Operating System (ROS), Gazebo and MATLAB. During that phase, functionalities of ROS, Gazebo and MATLAB were analyzed, and it was found how these components integrate between each other to build Astrobee flying software. Next, simulation of two Astrobees performing “in-home” and “torque” maneuvers was executed. After a successful completion of simulation, results of Astrobee’s trajectory was recorded. Then, …


Design And Analysis Of Fiber Reinforced Concrete Structure For Transportation Infrastructures, Salam Adil Mutlag Wtaife May 2019

Design And Analysis Of Fiber Reinforced Concrete Structure For Transportation Infrastructures, Salam Adil Mutlag Wtaife

Theses and Dissertations

Concrete is one of the most popular materials in superstructures (buildings), substructures (foundation) and infrastructure facilities (bridges, pavements, and tunnels). However, concrete is a brittle material that cracks easily under tension. Fiber may be used as reinforcement to impede the concrete from cracking as well as to increase the concrete flexural strength. Nevertheless, current design codes do not include this design enhancement. Furthermore, there are discrepancies in the design methodology concerning the inclusion of discrete fibers in concrete structures. Therefore; there is a need to develop new analysis methodology and design methodology for fiber reinforced concrete (FRC) and fiber reinforced …


Acceleration, Braking, And Steering Controller For Polaris Gem E2, Matthew Benton Salfer-Hobbs May 2019

Acceleration, Braking, And Steering Controller For Polaris Gem E2, Matthew Benton Salfer-Hobbs

Theses and Dissertations

This paper discusses the design and simulation of lane keeping and velocity controllers for a Polaris GEM e2. The controllers were designed to be implemented in Florida Institute of Technology’s entry for the Intelligent Ground Vehicle Competition self-drive challenge. The software and physical implementation of actuators were included to control the acceleration, braking, and steering. The accelerator pedal was replaced with a set of digitally controlled potentiometers, the brake pedal was replaced with a linear actuator, and the steering column was replaced with a stepper motor. Each actuator was controlled by a Raspberry Pi 3. A sliding mode controller was …


Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan May 2019

Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan

Theses and Dissertations

Membrane Hull Technology (MHT) was initially developed for the United States Navy Rigid-Hull Inflatable Boats (RHIB) as an alternative structure design to provide weight savings and shock mitigation. MHT accomplishes this by veering away from traditional hull design and utilizing a grid like system with an increased number of longitudinal stringers and transverse frames with a significantly lower moment of inertia when compared to traditional stringers and bulkheads. The decrease in stiffness allows for increased deflection in the hull during high load events with the added benefit of shock absorption. This technology, developed by Structural Composites Inc., has been successfully …


Feasibility Study And Hydrodynamics Of Transformable Submersible Hydrofoil Trimaran, Yipeng Pan May 2019

Feasibility Study And Hydrodynamics Of Transformable Submersible Hydrofoil Trimaran, Yipeng Pan

Theses and Dissertations

It has been the endeavor of naval architects to design innovative hull forms to address the political, socio-economic climate and sustainability around the world. It is imperative that countries be able to protect their sea lanes and coastal zones from surveillance and infiltration from hostile foreign entities. Hence there is a need to develop radically different hull form, which possess the elusive ability and are capable of high-speed. In order to fulfill the idea, the hypothesis envisioned in this thesis is: the Transformable Submersible Hydrofoil Trimaran (TSHT) as an innovative and ground breaking hull form would address the feasibility of …


Emerging App Issue Identification From User Feedback: Experience On Wechat, Cuiyun Gao, Wujie Zheng, Yuetang Deng, David Lo, Jichuan Zeng, Michael R. Lyu, Irwin King May 2019

Emerging App Issue Identification From User Feedback: Experience On Wechat, Cuiyun Gao, Wujie Zheng, Yuetang Deng, David Lo, Jichuan Zeng, Michael R. Lyu, Irwin King

Research Collection School Of Computing and Information Systems

It is vital for popular mobile apps with large numbers of users to release updates with rich features while keeping stable user experience. Timely and accurately locating emerging app issues can greatly help developers to maintain and update apps. User feedback (i.e., user reviews) is a crucial channel between app developers and users, delivering a stream of information about bugs and features that concern users. Methods to identify emerging issues based on user feedback have been proposed in the literature, however, their applicability in industry has not been explored. We apply the recent method IDEA to WeChat, a popular messenger …


A Queueing Theory-Based Modeling And Performance Analysis Of Push-To- Talk Over Cellular Networks, Hisham Zorghani May 2019

A Queueing Theory-Based Modeling And Performance Analysis Of Push-To- Talk Over Cellular Networks, Hisham Zorghani

Theses and Dissertations

Public Safety organizations play a vital role in emergencies. Their ultimate goal is to protect people and save lives and properties during disasters. Public safety communities have been using narrowband Trunking systems for their communications for decades. These systems were designed with only voice communications in mind. Even though these narrowband systems have gone throughout many enhancement phases, yet their data capabilities are still limited. Long Term Evolution (LTE) has been selected by many countries including the United States to be the platform for next-generation Public Safety Networks(PSN). The 3GPP LTE standard is all-IP architecture mainly developed to boost its …


Formal Trust Architecture For Assuring Trusted Interactions In The Internet Of Things, Milankumar Patel May 2019

Formal Trust Architecture For Assuring Trusted Interactions In The Internet Of Things, Milankumar Patel

Theses and Dissertations

The Internet of Things (IoT) has provided a flexible platform for a large number of heterogeneous devices to dynamically join and leave the network. This enhances the availability of a diverse range of services provided by a network. However, this dynamic expansion of the network with mobile IoT devices introduces a major challenge to security especially related to management of trust across the IoT platforms. Furthermore, IoT is open and distributed in nature, which allows the integration and registration of diverse entities. Thus arises the necessity for a mechanism that can ensure the selection of secure and trusted devices as …


Characterization Of Rf Signal Propagation For Wireless Sensor Network Deployed In Mountainous Environment, Bandar Mohammad Alshawi May 2019

Characterization Of Rf Signal Propagation For Wireless Sensor Network Deployed In Mountainous Environment, Bandar Mohammad Alshawi

Theses and Dissertations

Wireless sensor network (WSN) nodes, in mountainous forests, report real-time data to base stations concerning events, in which researchers and decision makers are interested in. A thorough research reveals the deficiency of any study modeling radio frequency (RF) in that environment. The lack of accurately modeling RF signal propagation in any environment can have a great impact on the network life, connectivity, and coverage. This dissertation models the loss of RF signal in the mountainous environment and demonstrates the inconsistency of theoretical models, compared to actual measurements. The models proposed in this research yield satisfactory results, and the theoretical models …


Wavelet–Based Functional Data Analysis For Classification And Change Point Detection, Nenad Mijatovic May 2019

Wavelet–Based Functional Data Analysis For Classification And Change Point Detection, Nenad Mijatovic

Theses and Dissertations

Data collection and analysis, performed close to the source and transferred to other devices for different analysis, are the major paradigms of the Internet of Things (IoT). Usually, the raw data comes in the form of a time-series sequence that can be considered as functions, and as such can be examined by the functional analysis apparatus. Among others, the two major tasks in data analysis are (1) categorical signal classification and (2) change detection in signal statistical parameters. Here, we study both problems: featureless signal classification using discriminative interpolation regularized with the ℓ1 norm is performed using Classification by Discriminative …


Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell May 2019

Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell

Theses and Dissertations

Resonant micro-electromechanical systems (MEMS) are increasingly common in applications, including inertial sensors and frequency sources. These devices operate at resonance and take advantage of their size, ability to integrate with electronics, and light damping. The performance of these devices can be improved by operation at higher vibration amplitudes, but they often begin to exhibit frequency shifts near resonance as the amplitude is increased, due to nonlinear stiffness effects. Previous works have sought to balance nonlinearities in order extend the linear dynamic range (LDR) of these resonators. The focus of this thesis is to characterize, for design purposes, another possible operating …


Lateral And Torsional Seismic Vibration Control For Torsionally Irregular Buildings, Osman Akyürek May 2019

Lateral And Torsional Seismic Vibration Control For Torsionally Irregular Buildings, Osman Akyürek

Theses and Dissertations

During strong earthquakes or wind gusts, it is likely that buildings with torsional irregularity in the plan have an can be seriously damaged, partially collapsed or fully collapsed. This is because Torsionally Irregular Buildings (TIBs) may have significant aerodynamic torsion loads that increase the eccentricity between the center of mass and the center of rigidity, especially in dominant torsion modes. For this reason, torsion leads to excessive increase in lateral motions when dynamic loads excite the buildings. Torsional irregularity is one of the main failure causes during strong dynamic excitations due to earthquakes or wind gusts. Ignoring torsional irregularity in …


Damping Coefficient Sensitivity Analysis Of High Rebound Soils In Florida, Aline Franqui May 2019

Damping Coefficient Sensitivity Analysis Of High Rebound Soils In Florida, Aline Franqui

Theses and Dissertations

The dynamic response of soils is related to a damping factor, which represents the energy absorbed by the soil as the pile moves. Certain blends of fine sands, silts and clays are producing pile rebound during driving. For that reason, the objective of this thesis is to conduct a damping coefficient sensitivity analysis of high rebound soils in Florida. Forty cyclic triaxial tests from six sites in Central and Northern Florida were analyzed to evaluate damping. Two approaches were used, one based on the change in stress over time and a second based on the viscous energy absorbed per cycle. …


Effect Of Industry Clusters And Commodity Flow Characteristics On The Selection Of Freight Transportation Modes In The United States With Advanced Econometric Approaches, Taleb Eissa Ali Eissa May 2019

Effect Of Industry Clusters And Commodity Flow Characteristics On The Selection Of Freight Transportation Modes In The United States With Advanced Econometric Approaches, Taleb Eissa Ali Eissa

Theses and Dissertations

Mode choice is an important strategic decision for shippers to carry commodities efficiently. Freight mode-choice is an important activity to develop a successful freight transportation business in the private sector and to plan for economically consistent freight transportation infrastructures in the public sector. Freight activities result from the complex interactions between different economic agents, but these relationships are commonly relaxed to account for three major agents: shippers, carriers and receivers. Furthermore, the behavior of freight choice is commonly not concentrated in one agent, but rather is divided jointly over multiple individuals and firms in a logistics process, each component of …