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Full-Text Articles in Engineering
A Parametric Evaluation Of Iot Applications To Freight Transportation Using Model-Based Systems Engineering, Paul George Crawford
A Parametric Evaluation Of Iot Applications To Freight Transportation Using Model-Based Systems Engineering, Paul George Crawford
Theses and Dissertations
Industrial Internet of Things or IIoT consists of computing and communication at the operational edge of a value chain. Applications span manufacturing, energy, and transportation, among others. In the transportation context, IIoT translates to connected vehicle architecture and ITS applications. Current trends in communication allow more applications and devices to contribute to functions traditionally allocated to transportation ITS infrastructure. This poses challenges to design engineers to prototype emerging technologies in the existing transportation context and reduce integration, validation, and time to market. Model-based systems engineering is crucial step for IIoT deployment since it allows for a feature-rich digital representation of …
Development Of A Deformation-Based Structural Health System With Contactless Sensors And Machine Learning For Health Characterization And Failure Prediction, Juan Camilo Avendano Arbelaez
Development Of A Deformation-Based Structural Health System With Contactless Sensors And Machine Learning For Health Characterization And Failure Prediction, Juan Camilo Avendano Arbelaez
Theses and Dissertations
This dissertation presents the design and development of a structural health monitoring (SHM) system specifically tailored for transportation infrastructure components, such as bridges. The proposed system collects data by using contactless sensors and performs health characterization and failure prediction. It is capable of simulating multiple load conditions on structures, identifying possible failure points, and detecting and predicting failure scenarios. Both hardware and software implementations of a model of a bridge were performed as a pilot project in order to validate the proposed system. Computer simulation in ANSYS and the application of gradient boosting neural networks were performed to produce a …
Flight Tests Of Trajectory Energy Management Systems Using A Vertical Takeoff And Landing Vehicle, Emils Senkans
Flight Tests Of Trajectory Energy Management Systems Using A Vertical Takeoff And Landing Vehicle, Emils Senkans
Theses and Dissertations
The rise of new aircraft propulsion methods (e.g. powered by batteries, fuel cells or hybrid electric systems), the increased use of automated and integrated flight control systems, and the envisioned use of personal Vertical Takeoff and Landing (VTOL) vehicles in urban environments (urban aerial mobility) leads to novel technical and regulatory challenges for aircraft manufacturers, certification authorities and operators. Of primary concern is operational safety, and closely connected pilot situation awareness and workload. A particular safety factor for operating VTOL vehicles that depend on propulsive lift for the majority of their operations and that are operated over urban terrain, is …
3d Printed Microporous Collagen Constructs Using The Freeze-Fresh Methodology, Thais Sousa Senzano
3d Printed Microporous Collagen Constructs Using The Freeze-Fresh Methodology, Thais Sousa Senzano
Theses and Dissertations
Scaffold microporosity is known to play a critical role in governing cellular response including cell migration, proliferation, and tissue-specific differentiation. While fabrication approaches such as solvent leaching and freeze-casting are commonly used for the generation of microporous biomaterial scaffolds, these methods provide little control over scaffold geometry and creation of complex tissue structures. Extrusion-based 3D printing, an additive manufacturing method, is a highly versatile layer-by-layer printing approach that allows for the fabrication of easily customizable 3D scaffolds with complex architecture using a vast selection of polymeric bioinks. These 3D printed constructs are porous at the macroscale, but achieving microporosity (i.e., < 100 μm) in printed constructs is challenging due to the sub-optimal resolution of the extrusion-based printing method. A recent study using alginate inks introduced a new fabrication technique termed Freeze-FRESH(FF)that combines extrusion printing and freeze-casting approaches to generate 3D constructs with hierarchical microporosity. However, the porosity of the resultant alginate constructs was comparable despite changing the freezing temperature. In the current study, the FF method was modified to print collagen constructs with greater control of microporous architecture. Highly concentrated collagen type I ink was used to 3D print collagen constructs using the freeform reversible embedding of suspended hydrogels (FRESH)approach. Modification of the FF technique entailed melting of the FRESH bath post printing via incubation at 37 °C followed by freezing and lyophilization to allow for collagen gelation and better heat transport during the freezing process. The effect of freezing temperature on micropore size, swelling degree, degradation, and mechanical properties of printed constructs was assessed. Finite element (FE) models were generated to predict the mechanical properties of microporous scaffolds. In addition, the effect of microporosity on Saos-2 cell morphology, proliferation, infiltration, and ALP activity was evaluated. Results from the study showed that freezing temperature effectively modulated micropore size and that constructs with larger micropore size were more stable. Microporosity had no effect on swelling ratio yet caused a decrease in mechanical properties of collagen constructs; FE models confirmed experimental results. Cell metabolic activity and infiltration was enhanced in microporous constructs with larger pore size, yet there was no effect on cell morphology, and ALP activity. In conclusion, the modified FF technique can be effectively used to fabricate hierarchically porous 3D collagen constructs.
Optimal Onboard Renewable Energy Charging Method To Improve Micro-Autonomous Underwater Vehicle Deployment Life, Brooklynn Dawn Byford
Optimal Onboard Renewable Energy Charging Method To Improve Micro-Autonomous Underwater Vehicle Deployment Life, Brooklynn Dawn Byford
Theses and Dissertations
This study is an investigation of various methods for recharging a micro autonomous underwater vehicle (μAUV) onboard using renewable energy sources while deployed at sea. The goal of this project is to determine the optimal onboard renewable energy design method to be used to prolong the deployment life of a μAUV. This project specifically targeted vehicles specifications and designs similar to the Riptide Autonomous Solutions’ μAUV[1], which was used for this study. Concluding results are based on the following factors: power generation versus time, structural integrity, and design complexity. The three design method categories investigated are as follows: solar energy, …
Framework For Reasoning With Speech Processing, Ahmed Laarfi
Framework For Reasoning With Speech Processing, Ahmed Laarfi
Theses and Dissertations
It is known that programming languages are textual. We try here to take the advantages of Speech Recognition (SR) and employ them in creating a verbal Language, which takes its instruction from the voice. Because this work is a novel approach in the programming world, we could not find any resources. This dissertation aims to make essential developments in Speech Recognition (SR)and Artificial Intelligence by constructing a new compiler that receives commands verbally and executes them. That means entering data into the Computer by voice commands. This method of input means that we link several major computer topics with several …
Modern Standard Arabic Speech Recognition: Using Formants Measurements To Extract Vowels From Arabic Words’ Consonant-Vowel-Consonant-Vowel Structure, Mohamed Ali Alshaari
Modern Standard Arabic Speech Recognition: Using Formants Measurements To Extract Vowels From Arabic Words’ Consonant-Vowel-Consonant-Vowel Structure, Mohamed Ali Alshaari
Theses and Dissertations
Arabic texts suffer from missing diacritics (short vowels) which become obstacles for new learners. Speech Recognition is the translation of words spoken to text through intelligent computer programs. As of today, it has been integrated into many computer systems. Arabic Speech Recognition has made progress over the years, but it is still not as good as English speech recognition due to the problem of short vowels not being recognized. This is mainly because the Arabic language is unlike the English language in the nature because it is a Semitic language. This is reflected in different characteristics such as grammar, morphology, …
Cloud Computing Service Interoperability And Architectural Concepts, Anmar Salih
Cloud Computing Service Interoperability And Architectural Concepts, Anmar Salih
Theses and Dissertations
Today’s market with a vast number of Cloud-computing providers creates a challenge for practical cooperation between the various provider cloud service platforms. Not only does Cloud interoperability provide this needed cooperation, but it also avoids vendor lock-in and, additionally, saves time and cost. Although there is no established definition for Cloud interoperability, most researchers agree on the purposes of Cloud interoperability. Research and literature have attempted to explain interoperability as transferring data, moving workloads, and migrating virtual machines between Cloud platforms. Transferring data between Clouds refers to objects migrating between provider-specific domains. In comparison, data migration is the most commonly …
Test And Evaluation Of An Artec Leo 3d Scanner, Chelsea Alexis Reichard
Test And Evaluation Of An Artec Leo 3d Scanner, Chelsea Alexis Reichard
Theses and Dissertations
With new and innovative technologies, companies have begun utilizing 3-Dimensional Scanners to reverse engineer objects of virtually any size or complexity. These scanners increase efficiency, allowing companies to import physical items into the computer without the hassle of modeling it themselves in Computer Aided Design (CAD) software. Although these highly advanced devices can be very fast and effective, we will be studying the surfaces that are incompatible to these scanners. The study performed in this research will test the limitations of a new, highly advanced, wireless 3D Scanner; The Artec Leo. For many scanners, including the one used in this …
Measuring Pilot Control Force In General Aviation: Strain Gauges And Load Cell, Benjamin David Wyma
Measuring Pilot Control Force In General Aviation: Strain Gauges And Load Cell, Benjamin David Wyma
Theses and Dissertations
Flight test requires a variety of sensors and data systems to accurately read variables on an aircraft during testing. One of these important variables is the pilots control force. Control force is used in many tests in flight test to ensure the aircraft being tested meets the required FAA standards. One essential test is stick free longitudinal stability where control force is needed to calculate the stick free neutral points of the aircraft [1]. The objective of the project was to explore two methods of electronically measuring control force and determining which method is best suited for Florida Institute of …
Existence Of Ballistic Capture Transfer Trajectories From Trans-Lunar Injection To Lunar Polar Orbit For All Lunar Phases At Time Of Departure, Anthony Lawrence Genova
Existence Of Ballistic Capture Transfer Trajectories From Trans-Lunar Injection To Lunar Polar Orbit For All Lunar Phases At Time Of Departure, Anthony Lawrence Genova
Theses and Dissertations
This dissertation reveals several families of trajectories that can reduce the change in velocity(ΔV) required to transfer from trans-lunar injection (TLI) to a lunar polar circular orbit with 100 km altitude by up to 26.5% compared to conventional transfers. The primary hypothesis states that such trajectories, termed lunar polar ballistic capture (LPBC) transfers, exist for all lunar phases at the time of lunar departure (i.e., initial lunar flyby).The existence of LPBC transfers for all lunar phases can enable missions with ride-share restrictions (CubeSat), limited propellant capability (small spacecraft), and/or payloads that are not time sensitive (cargo).Evidence to support the primary …
Improving Long-Term Vascular Graft Viability Using Peritoneal Pre-Implantation And Epsin-Mimetic Peptides, Mahyar Sameti
Improving Long-Term Vascular Graft Viability Using Peritoneal Pre-Implantation And Epsin-Mimetic Peptides, Mahyar Sameti
Theses and Dissertations
The primary goal of this project was to produce and develop a tissue-engineered small-diameter vascular graft which can replace the arteries and function well for long-term grafting. Implanting an electrospun tubular conduit into the peritoneal cavity to recruit autologous cells prior to grafting the conduit into the artery is a method to achieve this goal. Incorporating an epsin-mimetic peptide on the conduit prior to grafting is another proposed method to reach the goal. This will be accomplished through four complementary studies: (1) determining the effect of a pouch in peritoneal pre-implantation and reducing the potential peritoneal adhesion formation;(2) determining the …
Efficient Edge Analytics: Addressing Cyber-Physical Masint With Machine Learning On Audio At The Edge, David Elliott
Efficient Edge Analytics: Addressing Cyber-Physical Masint With Machine Learning On Audio At The Edge, David Elliott
Theses and Dissertations
With the growth of the Internet of Things and the rise of Big Data, data processing and machine learning applications are being moved to cheap and low size, weight, and power (SWaP) devices at the edge, often in the form of mobile phones, embedded systems, or microcontrollers. The field of Cyber-Physical Measurements and Signature Intelligence (MASINT) makes use of these devices to analyze and exploit data in ways not otherwise possible, which results in increased data quality, increased security, and decreased bandwidth. However, methods to train and deploy models at the edge are limited, and models with sufficient accuracy are …
A Modified Peng-Robinson Cubic Equation Of State Based On Bayesian Framework, Wei Chen
A Modified Peng-Robinson Cubic Equation Of State Based On Bayesian Framework, Wei Chen
Theses and Dissertations
Peng-Robinson cubic equations of state (PR-EoSs) as one of the most popular two-parameter cubic equations of state (2P-EoSs) are widely used to calculate thermodynamic properties of pure substances and their mixtures. However, the prediction accuracy of 2P-EoSs varies significantly among different substances due to its intrinsic limitation. To this end, many modifications have focused on changing the dependence structure of 𝛼 function with temperature for PR-EoS to enhance prediction accuracy. In this paper, we propose a Bayesian framework to calibrate a new 𝛼 function, which is a bias-corrected parametrized model form for the PR-EoS. The developed PR-EoS with the calibrated …
The Effect Of Intensive Auditory Cues On Flight Passengers’ Safe Behaviors, Tianhua Li
The Effect Of Intensive Auditory Cues On Flight Passengers’ Safe Behaviors, Tianhua Li
Theses and Dissertations
When passengers do not follow in-flight announcements, injuries can occur. It is critical to draw passengers’ attention and help them be aware of the importance of the instructions provided during in-flight announcements. Passengers’ attention can be improved by providing intensive auditory cues before announcements. The auditory cues with intensive acoustic parameters increase the hearers’ perceived level of urgency, and then, they are more likely to perform safer behaviors. Also, when the intensity level increases to an intermediate level, the stimulated persons should have better performance. However, when it increases excessively, their performance may be impaired. The study examined the effect …
Assessing The Methodological Quality Of Aviation Research: A Content Analysis Of Articles Published In Subscription And Open Access Aviation Journals 2014-2016, Isa Tuncman
Theses and Dissertations
The purpose of the study was to determine to what extent aviation research articles were consistent with commonly recommended research protocols. Using a purposive sampling strategy, two subscription and five open access journals published from 2014 to 2016 were targeted, and 139 articles were reviewed using a category based, researcher-developed coding form grounded in commonly accepted research practices presented in educational research methods textbooks. The form reflected models from the medical research community and employed a 3-point scoring rubric: 0 = Not Reported, 1 = Inadequate, and 2 = Adequate. At least two coders reviewed each article, and corresponding Krippendorff …
Development Of Nirs Based Noninvasive Cerebrovascular Regulation Assessment, Stephanie Marie Miller
Development Of Nirs Based Noninvasive Cerebrovascular Regulation Assessment, Stephanie Marie Miller
Theses and Dissertations
Alterations to cerebral blood flow (CBF) have been implicated in diverse neurological conditions, including mild traumatic brain injury, microgravity induced intracranial pressure (ICP) and intraocular pressure (IOP) increases, and mild cognitive impairment. Near infrared spectroscopy (NIRS)-measured regional cerebral tissue oxygen saturation (rSO2) provides an estimate of oxygenation of the interrogated cerebral volume that is useful in identifying trends and changes in oxygen supply to cerebral tissue and has been used to monitor cerebrovascular function during surgery and ventilation. In this study, CO2-inhalation-based hypercapnic breathing challenges were used as a tool to simulate CBF dysregulation, and NIRS was used to monitor …
Salt Transport To Saturated Porous Media Under Unstable Conditions: Experimental, Analytical, And Numerical Studies, Kamal Mamoua
Salt Transport To Saturated Porous Media Under Unstable Conditions: Experimental, Analytical, And Numerical Studies, Kamal Mamoua
Theses and Dissertations
There are three main transport mechanisms that occur under unstable flow conditions: a) The transport of saltwater from the overlying salt source to the underlying porous media, b) the transport of an equivalent volume of displaced groundwater from the porous media into the source, and c) the transport of the saltwater through the porous media. In many situations; such as, estuaries, salt lakes, and landfills, it may be necessary to determine the rate of saltwater transport from an overlying unstable salt source that has heavier saline water overlying porous media fully saturated by lighter saline water. Studies of unstable density …
Evaluation Of Accumulated Strain From Both Cyclic Triaxial And Static Creep Tests On Unbound Pavement Materials, Amir Mohammad Sajjadi
Evaluation Of Accumulated Strain From Both Cyclic Triaxial And Static Creep Tests On Unbound Pavement Materials, Amir Mohammad Sajjadi
Theses and Dissertations
In this research, the behavior of Limerock (LR) aggregates blended with different reclaimed asphalt pavement (RAP) materials were investigated as an unbound base layer. Various combinations of LR and RAP, including 100%LR, 25%RAP75%LR, 50%RAP50%LR, and 100%RAP, were evaluated. Three main experiments performed on the samples were: static creep, static triaxial test, and cyclic triaxial test. The cyclic triaxial test was performed to measure the resilient modulus (MR) of materials. The results of the static triaxial test for 100% RAP showed that the deviator stress at failure steadily increased by increasing the confining pressure, while the 100% LR showed a maximum …
Finite Element Method For Assessment Of Air Cushion Skirt Performance, Thomas Arthur Lipscomb
Finite Element Method For Assessment Of Air Cushion Skirt Performance, Thomas Arthur Lipscomb
Theses and Dissertations
The objective of this thesis is to create a method of simulating the performance of new materials for use in air cushion vehicle skirts. These systems currently exhibit unacceptable design lifetimes to be considered for widespread adoption, except in specific applications such a military or rapid transport, where high cost is not an obstacle. This project also focuses on using a new high strain to failure resin system that has recently been developed, in combination with high performance reinforcing fibers, to increase the lifespan of the skirt systems. Using industry-standard finite element modelling (FEM) software, a 3d model of the …
A Finite State Automata-Based Description Of Device States For Function Modeling Of Multi-State Technical Devices, Ahmed Mohammed Sobhan Chowdhury
A Finite State Automata-Based Description Of Device States For Function Modeling Of Multi-State Technical Devices, Ahmed Mohammed Sobhan Chowdhury
Theses and Dissertations
Many modern and innovative design problems require multi-modal, reconfigurable solutions. Function modeling (FM) is a common tool used to explore solutions in early stages of mechanical engineering design. Currently, function structure representations do not abet the modeling of formally-defined reconfigurable function models as graph-based function models used in early-stage systems design usually represent only one operational mode of the system. Currently there is a need, but no rigorous formalism to model multiple possible modes in the model and logically predict the behavior of the system as it transitions between the modes. Additionally, function modeling representations will benefit from dynamically capturing …
Correlation Between Air Quality Index And Traffic Volume Using Internet Of Things (Iot), Omar Sayah Alruwaili
Correlation Between Air Quality Index And Traffic Volume Using Internet Of Things (Iot), Omar Sayah Alruwaili
Theses and Dissertations
In highly populated world areas, such as metropolises, hazardous air pollution has been linked to the presence of damaging climate and health issues, which are becoming increasingly common. Indeed, a major problem facing urban areas today is air pollution. Gas emissions from vehicles can be seen as the most important source of this kind of pollution. Pollutant gases emitted as parts of car exhaust consist of chemicals such as carbon monoxide (CO), nitrogen dioxide (NO2), and sulphur dioxide (SO2), and ozone (O3), as well as particulate matter (PM). In some places in the world, non-governmental and foreign corporations have also …
Development Of A Design Method For Bonded Concrete Pavement Overlays, Ahmed Alsabbagh
Development Of A Design Method For Bonded Concrete Pavement Overlays, Ahmed Alsabbagh
Theses and Dissertations
Several asphalt pavements prematurely reached the end of their design life due to wheel loading has dramatically increased on highways. Therefore, transportation and highways agencies often endeavor to provide high-performance pavement to ensure the longest life with low maintenance required. Although asphalt pavement overlay (APO) can provide a quick and low-cost option for pavements rehabilitation, it frequently exhibits excessive rutting especially at highway pavement subjected to stop-and-go traffic conditions. Hence, concrete pavement overlays (CPO) is one of the alternative options for rehabilitating deteriorated pavements. The ultra-thin white topping (UTW) is one type of concrete overlay types and is considered a …
Extreme Response Analysis Of A Site-Specific Offshore Wind Turbine And Offshore Wind Farm Layout Optimization, Xiaosen Xu
Theses and Dissertations
Offshore floating wind turbines have been developed in deep water where bottom-fixed offshore wind turbines are cost-prohibitive. Gulf of Maine has one of the greatest potential wind energy on the east coast. A detailed analysis of metocean data is essential for the dynamic simulation of the floating offshore wind turbine and the offshore wind farm layout optimization. Wave scatter diagram represents the joint probability of significant wave height and peak periods. In the wind energy industry, turbulence intensity is defined as the standard deviation of the horizontal wind speed divided by the average wind speed over certain time period. Uniform …
An Empirical Investigation Of The Dimensions Of Product Similarity Used In Design By Analogy Of Electromechanical Products, Arnold Nkoane Tsoka
An Empirical Investigation Of The Dimensions Of Product Similarity Used In Design By Analogy Of Electromechanical Products, Arnold Nkoane Tsoka
Theses and Dissertations
Analogical reasoning is known to be a core cognitive mechanism behind creative human tasks including the creativity in engineering design. Research shows that during product ideation, designers use analogy to transfer information from prior designs stored in their memory (the source of the analogy) to the task in hand (target of analogy). However, similar to any search process, the source product must be first identified as a potential candidate for analogy before this information transfer can take place. Two products can be similar along multiple dimensions such as their form, function, etc. The dimensions of similarity between two products that …
Application Of Classification In Machine Learning: An Analysis Of Highway-Rail Grade Crossing Systems Safety, Christopher John Helmer Cox
Application Of Classification In Machine Learning: An Analysis Of Highway-Rail Grade Crossing Systems Safety, Christopher John Helmer Cox
Theses and Dissertations
Highway-rail grade crossing accidents are the second leading cause of fatalities within the railway transportation industry. Highway-rail grade crossing fatality statistics have failed to improve over the last decade, and in some years have increased. Because of these trends, research has found that considerable Federal funding initiatives exist to support and develop contemporary risk reduction methodologies involving machine learning and artificial intelligence. In accord with these initiatives, this thesis investigates the highway-rail grade crossing safety problem using machine learning to implement an ensemble decision tree-based classification application. The resulting classifier has been validated to achieve a less than three percent …
Development Of A Graphical User Interface For Ecg Signals Classification Using Statistical Features Analysis, Mousa Hammad S Aldosari
Development Of A Graphical User Interface For Ecg Signals Classification Using Statistical Features Analysis, Mousa Hammad S Aldosari
Theses and Dissertations
Cardiac diseases are the most common cause of mortality in the world. The detection of cardiac arrhythmias is not a straightforward process, since minor variations in the electrocardiogram (ECG) signals cannot be easily identified manually. Therefore, automatic detection and classification of cardiac arrhythmia would shorten the diagnostic time and accelerate medical intervention resulting in reducing the mortality rate. In this thesis, I have developed a simple and low-cost computer-aided diagnostic system using MATLAB-based Graphical User Interface (GUI) to facilitate fast operation and access to the data along with the overall accuracy of the system. The acquired ECG signals are processed …
Airline Brand Experience Passengers’ Perceptions Of The Big Three Carriers In The United States, Sarinthree Udchachone
Airline Brand Experience Passengers’ Perceptions Of The Big Three Carriers In The United States, Sarinthree Udchachone
Theses and Dissertations
The purpose of the study was to observe passengers’ perceptions about brand experience research in the airline industry by applying a transcendental or descriptive phenomenological methodology designed to evaluate interview transcriptions and organize derived knowledge into defined themes. The NVivo program was utilized to analyze data from textual transcriptions. The experiences of passengers of the Big Three United States legacy carriers, including American Airlines, Delta Air Lines, and United Airlines, were described. The participants comprised three couples and seven individuals, all frequent-flyer members of the Big Three carriers and their partnering global airline alliances. The researcher-constructed instrument was used for …
A Quantitative Analysis Of The Robinson R44 Performance Characteristics, Jon Carroll Holzman
A Quantitative Analysis Of The Robinson R44 Performance Characteristics, Jon Carroll Holzman
Theses and Dissertations
The Robinson R44 is the most prolific civil helicopter in the world with over 6,000 delivered to customers since 1992. Approved for normal category flight by the FAA through 14 CFR Parts 21 and 27, the accompanying Pilot's Operating Handbook includes all performance material required under the same. Practical planning materials, such as cruise charts and accompanying fuel flow rates for various operational weights and density altitudes, however, are absent. This leaves a large gap in flight planning resources needed for an airframe which is currently being used in a broad range of demanding civil capacities to include offshore oil …
Application Of Neural Networks For Solving One Dimensional Inverse Heat Conduction Problems With Surface Ablation, Jian Zhang
Theses and Dissertations
Thermal protection systems (TPS) are critical for space vehicles to keep them safe against extensive aerothermal heating, particularly during the atmospheric entry. Ablative materials burn away gradually when subjected to extreme heat flux and therefore are considered as a practical option for TPS application. Measurement of TPS surface condition, particularly heat flux, is essential to reduce design margins and also improve active control strategies for damage avoidance. However, it is not possible to directly measure TPS surface heat flux, and alternative approaches must be utilized for this purpose. One method is to use temperature sensors at internal layers and solve …