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Articles 42181 - 42210 of 196421

Full-Text Articles in Engineering

An Effective Prediction Method For Network State Information In Sd-Wan, Erdal Akin, Ferdi̇ Saraç, Ömer Aslan Jan 2022

An Effective Prediction Method For Network State Information In Sd-Wan, Erdal Akin, Ferdi̇ Saraç, Ömer Aslan

Turkish Journal of Electrical Engineering and Computer Sciences

In a software-defined wide area network (SD-WAN), a logically centralized controller is responsible for computing and installing paths in order to transfer packets among geographically distributed locations and remote users. Accordingly, this would necessitate obtaining the global view and dynamic network state information (NSI) of the network. Therefore, the centralized controller periodically collects link-state information from each port of each switch at fixed time periods. While collecting NSI in short periods causes protocol overhead on the controller, collecting in longer periods leads to obtaining inaccurate NSI. In both cases, packet losses are inevitable, which is not preferred for quality of …


Temporal Bagging: A New Method For Time-Based Ensemble Learning, Göksu Tüysüzoğlu, Derya Bi̇rant, Volkan Kiranoğlu Jan 2022

Temporal Bagging: A New Method For Time-Based Ensemble Learning, Göksu Tüysüzoğlu, Derya Bi̇rant, Volkan Kiranoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

One of the main problems associated with the bagging technique in ensemble learning is its random sample selection in which all samples are treated with the same chance of being selected. However, in time-varying dynamic systems, the samples in the training set have not equal importance, where the recent samples contain more useful and accurate information than the former ones. To overcome this problem, this paper proposes a new time-based ensemble learning method, called temporal bagging (T-Bagging). The significant advantage of our method is that it assigns larger weights to more recent samples with respect to older ones, so it …


An Active Contour Model Using Matched Filter And Hessian Matrix For Retinalvessels Segmentation, Mahtab Shabani, Hossein Pourghassem Jan 2022

An Active Contour Model Using Matched Filter And Hessian Matrix For Retinalvessels Segmentation, Mahtab Shabani, Hossein Pourghassem

Turkish Journal of Electrical Engineering and Computer Sciences

Medical image analysis, especially of the retina, plays an important role in diagnostic decision support tools. The properties of retinal blood vessels are used for disease diagnoses such as diabetes, glaucoma, and hypertension. There are some challenges in the utilization of retinal blood vessel patterns such as low contrast and intensity inhomogeneities. Thus, an automatic algorithm for vessel extraction is required. Active contour is a strong method for edge extraction. However, it cannot extract thin vessels and ridges very well. In this research, we propose an improved active contour method that uses discrete wavelet transform for energy minimization to solve …


Stressed Or Just Running? Differentiation Of Mental Stress And Physical Activityby Using Machine Learning, Yekta Sai̇d Can Jan 2022

Stressed Or Just Running? Differentiation Of Mental Stress And Physical Activityby Using Machine Learning, Yekta Sai̇d Can

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, modern people have excessive stress in their daily lives. With the advances in physiological sensors and wearable technology, people?s physiological status can be tracked, and stress levels can be recognized for providing beneficial services. Smartwatches and smartbands constitute the majority of wearable devices. Although they have an excellent potential for physiological stress recognition, some crucial issues need to be addressed, such as the resemblance of physiological reaction to stress and physical activity, artifacts caused by movements and low data quality. This paper focused on examining and differentiating physiological responses to both stressors and physical activity. Physiological data are collected …


Investigation Of Domestic Level Ev Chargers In The Distribution Network: An Assessment And Mitigation Solution, Arsalan Hussain Zaidi Jan 2022

Investigation Of Domestic Level Ev Chargers In The Distribution Network: An Assessment And Mitigation Solution, Arsalan Hussain Zaidi

Doctoral

This research focuses on the electrification of the transport sector. Such electrification could potentially pose challenges to the distribution system operator (DSO) in terms of reliability, power quality and cost-effective implementation. This thesis contributes to both, an Electrical Vehicle (EV) load demand profiling and advanced use of reactive power compensation (D-STATCOM) to facilitate flexible and secure network operation. The main aim of this research is to investigate the planning and operation of low voltage distribution networks (LVDN) with increasing electrical vehicles (EVs) proliferation and the effects of higher demand charging systems. This work is based on two different independent strands …


Ammonia Cycling And Emerging Particulate Matter Pollutants Under Arable Land-Use Management: A Modelling Approach, Vivien Pohl Jan 2022

Ammonia Cycling And Emerging Particulate Matter Pollutants Under Arable Land-Use Management: A Modelling Approach, Vivien Pohl

Doctoral

Air quality monitoring in Ireland is under the jurisdiction of the Environmental Protection Agency in compliance with the Gothenburg Protocol, EU/national legislation, and the National Clean Air Strategy. Particulate Matter (PM) has been acknowledged as a key atmospheric pollutant, with serious public health impacts and no safe threshold of exposure in place to-date. Ammonia (NH3) emissions are linked to the secondary production of PM through atmospheric reactions occurring with acidic atmospheric components such as sulfuric acid, nitric acid, and hydrochloric acid. These reactions result in the formation of ammonium sulfate, ammonium nitrate and ammonium chloride, among others. More than 95% …


Artificial Intelligence-Based Material Discovery For Clean Energy Future, Reza Maleki, Mohsen Asadnia, Amir Razmjou Jan 2022

Artificial Intelligence-Based Material Discovery For Clean Energy Future, Reza Maleki, Mohsen Asadnia, Amir Razmjou

Research outputs 2022 to 2026

Artificial intelligence (AI)-assisted materials design and discovery methods can come to the aid of global concerns for introducing new efficient materials in different applications. Also, a sustainable clean future requires a transition to a low-carbon economy that is material-intensive. AI-assisted methods advent as inexpensive and accelerated methods in the design of new materials for clean energies. Herein, the emerging research area of AI-assisted material discovery with a focus on developing clean energies is discussed. The applications, advantages, and challenges of using AI in material discovery are discussed and the future perspective of using AI in clean energy is studied. This …


Towards A Digital Twin For Characterising Natural Source Zone Depletion: A Feasibility Study Based On The Bemidji Site, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner Jan 2022

Towards A Digital Twin For Characterising Natural Source Zone Depletion: A Feasibility Study Based On The Bemidji Site, Kaveh Sookhak Lari, Greg B. Davis, John L. Rayner

Research outputs 2022 to 2026

Natural source zone depletion (NSZD) of light non-aqueous phase liquids (LNAPLs) may be a valid long-term management option at petroleum impacted sites. However, its future long-term reliability needs to be established. NSZD includes partitioning, biotic and abiotic degradation of LNAPL components plus multiphase fluid dynamics in the subsurface. Over time, LNAPL components are depleted and those partitioning to various phases change, as do those available for biodegradation. To accommodate these processes and predict trends and NSZD over decades to centuries, for the first time, we incorporated a multi-phase multi-component multi-microbe non-isothermal approach to representatively simulate NSZD at field scale. To …


Optimum Geological Storage Depths For Structural H2 Geo-Storage, Stefan Iglauer Jan 2022

Optimum Geological Storage Depths For Structural H2 Geo-Storage, Stefan Iglauer

Research outputs 2022 to 2026

H2 geo-storage has been suggested as a key technology with which large quantities of H2 can be stored and withdrawn again rapidly. One option which is currently explored is H2 storage in sedimentary geologic formations which are geographically widespread and potentially provide large storage space. The mechanism which keeps the buoyant H2 in the subsurface is structural trapping where a caprock prevents the H2 from rising by capillary forces. It is therefore important to assess how much H2 can be stored via structural trapping under given geo-thermal conditions. This structural trapping capacity is thus …


Application Of Neuromorphic Olfactory Approach For High-Accuracy Classification Of Malts, Anup Vanarse, Adam Osseiran, Alexander Rassau, Peter Van Der Made Jan 2022

Application Of Neuromorphic Olfactory Approach For High-Accuracy Classification Of Malts, Anup Vanarse, Adam Osseiran, Alexander Rassau, Peter Van Der Made

Research outputs 2022 to 2026

Current developments in artificial olfactory systems, also known as electronic nose (e-nose) systems, have benefited from advanced machine learning techniques that have significantly improved the conditioning and processing of multivariate feature-rich sensor data. These advancements are complemented by the application of bioinspired algorithms and architectures based on findings from neurophysiological studies focusing on the biological olfactory pathway. The application of spiking neural networks (SNNs), and concepts from neuromorphic engineering in general, are one of the key factors that has led to the design and development of efficient bioinspired e-nose systems. However, only a limited number of studies have focused on …


A New Comprehensive Dimensionless Inflow Performance Relationship For Gas Wells, Azim Kalantariasl, Isa Farhadi, Soosan Farzani, Alireza Keshavarz Jan 2022

A New Comprehensive Dimensionless Inflow Performance Relationship For Gas Wells, Azim Kalantariasl, Isa Farhadi, Soosan Farzani, Alireza Keshavarz

Research outputs 2022 to 2026

Prediction of gas well deliverability is important for reservoir management. Conventional flow after flow, isochronal or modified isochronal tests are common methods for calculation of well deliverability. Single-point test using Vogel-type dimensionless inflow performance relationships (IPR) was also proposed to overcome the need for multi-point tests. However, analysis of field data showed that existing dimensionless IPR correlations fail to accurately predict well deliverability for some reservoir conditions. In this study, a wide range of reservoir rock and fluid data was used to develop a comprehensive dimensionless IPR correlation for calculation of gas well deliverability from single-point test data. Multi-point well …


Application Of Benchtop Humidity And Temperature Chamber In The Measurement Of Water Vapor Sorption In Us Shales From Mancos, Marcellus, Eagle Ford And Wolfcamp Formations, Hesham Abdulelah, Berihun Mamo Negash, Atta Dennis Yaw, Tareq M. Al-Shami, Ahmed Al-Yaseri, Eswaran Padmanabhan Jan 2022

Application Of Benchtop Humidity And Temperature Chamber In The Measurement Of Water Vapor Sorption In Us Shales From Mancos, Marcellus, Eagle Ford And Wolfcamp Formations, Hesham Abdulelah, Berihun Mamo Negash, Atta Dennis Yaw, Tareq M. Al-Shami, Ahmed Al-Yaseri, Eswaran Padmanabhan

Research outputs 2022 to 2026

A benchtop humidity and temperature chamber was used to assess water vapor sorption in four US shale samples at 90 °C. Water sorption isotherms were measured at relative humidity ranging from 10 to 99% and temperature of 90 °C. Shale fractal properties were then evaluated, and capillary pressure (ranging from 1.70 to 386 MPa) was obtained using Kelvin relationship. The results show that Mancos shale, from the US, adsorbed more absorbed water due to its high clay concentration and low TOC. However, Wolfcamp shale, from the US, has the lowest TOC and clay concentration, adsorbing the lowest amount of water. …


Evaluation Of The Mechanical Properties And Drilling Of Glass Bead/Fiber-Reinforced Polyamide 66 (Pa66)-Based Hybrid Polymer Composites, Recep Demirsöz, Nafiz Yasar, Mehmet Erdi Korkmaz, Mustafa Günay, Khaled Giasin, Danil Yorievich Pimenov, Muhammad Aamir, Huseyin Unal Jan 2022

Evaluation Of The Mechanical Properties And Drilling Of Glass Bead/Fiber-Reinforced Polyamide 66 (Pa66)-Based Hybrid Polymer Composites, Recep Demirsöz, Nafiz Yasar, Mehmet Erdi Korkmaz, Mustafa Günay, Khaled Giasin, Danil Yorievich Pimenov, Muhammad Aamir, Huseyin Unal

Research outputs 2022 to 2026

In this study, mechanical testing of glass bead (GB), glass fiber (GF), and hybrid (GB/GF) composites was carried out. Following that, drilling tests were undertaken on glass bead/fiber-reinforced hybrid Polyamide 66 (PA66) polymer composites. The purpose of this study is to determine the mechanical properties of the cutting elements and the effect of cutting parameters (spindle speed and feed rate) and reinforcement ratios on thrust force and surface roughness (Ra). The contribution of the cutting parameters to the investigated outcomes was determined using statistical analysis. Optical microscopy and scanning electron microscopy (SEM) was used to inspect the hole quality and …


Measurement Of Orientation And Distance Change Using Circularly Polarized Uwb Signals, Janusz Przewocki, Max Ammann, Adam Narbudowicz Jan 2022

Measurement Of Orientation And Distance Change Using Circularly Polarized Uwb Signals, Janusz Przewocki, Max Ammann, Adam Narbudowicz

Articles

The article proposes methodology to use circularly polarized (CP) ultra-wideband (UWB) signals for simultaneous measurement of orientation and distance changes between transmitter and receiver. The proposed technique uses the rotational Doppler effect on CP pulsed communication. The amplitude of a CP signal is immune to polarization misalignment in the presence of rotation; however, the phase is subjected to a frequency-invariant shift proportional to the rotation angle. This significantly distorts the pulse shape in the time domain and can be used for the measurement of the rotated angle. By combining the technique with the well-known localization capability of UWB systems, one …


Effect Of Carbon Fibres On Electromagnetic-Interference-Shielding Properties Of Geopolymer Composites, Dimuthu Wanasinghe, Farhad Aslani, Guowei Ma Jan 2022

Effect Of Carbon Fibres On Electromagnetic-Interference-Shielding Properties Of Geopolymer Composites, Dimuthu Wanasinghe, Farhad Aslani, Guowei Ma

Research outputs 2022 to 2026

Many of the construction materials available are known to cause a drastic level of damage to the environment during their manufacturing stages. Hence, many researchers have attempted to formulate construction materials that are more environmentally friendly. Additionally, the rise in wireless communications in recent decades has seen a rapid increase in electromagnetic pollution and interference, which affects the functionality of sensitive electronic devices. This research is focused on fabricating a more sustainable construction material that could prevent electromagnetic interference for electronic devices housed inside. Carbon fibres of three different lengths were added in four variations to a geopolymer control mix …


High Latency Unmanned Ground Vehicle Teleoperation Enhancement By Presentation Of Estimated Future Through Video Transformation, Md Moniruzzaman, Alexander Rassau, Douglas Chai, Syed Mohammed Shamsul Islam Jan 2022

High Latency Unmanned Ground Vehicle Teleoperation Enhancement By Presentation Of Estimated Future Through Video Transformation, Md Moniruzzaman, Alexander Rassau, Douglas Chai, Syed Mohammed Shamsul Islam

Research outputs 2022 to 2026

Long-distance, high latency teleoperation tasks are difficult, highly stressful for teleoperators, and prone to over-corrections, which can lead to loss of control. At higher latencies, or when teleoperating at higher vehicle speed, the situation becomes progressively worse. To explore potential solutions, this research work investigates two 2D visual feedback-based assistive interfaces (sliding-only and sliding-and-zooming windows) that apply simple but effective video transformations to enhance teleoperation. A teleoperation simulator that can replicate teleoperation scenarios affected by high and adjustable latency has been developed to explore the effectiveness of the proposed assistive interfaces. Three image comparison metrics have been used to fine-tune …


Deep Learning Inspired Feature Engineering For Classifying Tremor Severity, Ahmed Al Taee, Seyedehmarzieh Hosseini, Rami N. Khushaba, Tanveer Zia, Chin-Teng Lin, Adel Al-Jumaily Jan 2022

Deep Learning Inspired Feature Engineering For Classifying Tremor Severity, Ahmed Al Taee, Seyedehmarzieh Hosseini, Rami N. Khushaba, Tanveer Zia, Chin-Teng Lin, Adel Al-Jumaily

Research outputs 2022 to 2026

Bio-signals pattern recognition systems can be impacted by several factors with a potential to limit their associated performance and clinical translation. Among these factors, selecting the optimum feature extraction method, that can effectively exploit the interaction between the temporal and spatial information, is the most prominent. Despite the potential of deep learning (DL) models for extracting temporal, spatial, or temporal-spatial information, they are typically restricted by their need for a large amount of training data. The deep wavelet scattering transform (WST) is a relatively recent advancement within the DL literature to replace expensive convolution neural networks models with computationally less …


Fine-Grained Ship Image Recognition Based On Bcnn With Inception And Am-Softmax, Zhilin Zhang, Ting Zhang, Zhaoying Liu, Peijie Zhang, Shanshan Tu, Yujian Li, Muhammad Waqas Jan 2022

Fine-Grained Ship Image Recognition Based On Bcnn With Inception And Am-Softmax, Zhilin Zhang, Ting Zhang, Zhaoying Liu, Peijie Zhang, Shanshan Tu, Yujian Li, Muhammad Waqas

Research outputs 2022 to 2026

The fine-grained ship image recognition task aims to identify various classes of ships. However, small inter-class, large intra-class differences between ships, and lacking of training samples are the reasons that make the task difficult. Therefore, to enhance the accuracy of the fine-grained ship image recognition, we design a fine-grained ship image recognition network based on bilinear convolutional neural network (BCNN) with Inception and additive margin Softmax (AM-Softmax). This network improves the BCNN in two aspects. Firstly, by introducing Inception branches to the BCNN network, it is helpful to enhance the ability of extracting comprehensive features from ships. Secondly, by adding …


Insights Into The Aerodynamic Versus Radiometric Surface Temperature Debate In Thermal-Based Evaporation Modeling, Kaniska Mallick, Dennis Baldocchi, Andrew Jarvis, Tian Hu, Ivonne Trebs, Mauro Sulis, Nishan Bhattarai, Christian Bossung, Yomna Eid, Jamie Cleverly, Jason Beringer, William Woodgate, Richard Silberstein, Nina Hinko-Najera, Wayne S. Meyer, Darren Ghent, Zoltan Szantoi, Gilles Boulet, William P. Kustas Jan 2022

Insights Into The Aerodynamic Versus Radiometric Surface Temperature Debate In Thermal-Based Evaporation Modeling, Kaniska Mallick, Dennis Baldocchi, Andrew Jarvis, Tian Hu, Ivonne Trebs, Mauro Sulis, Nishan Bhattarai, Christian Bossung, Yomna Eid, Jamie Cleverly, Jason Beringer, William Woodgate, Richard Silberstein, Nina Hinko-Najera, Wayne S. Meyer, Darren Ghent, Zoltan Szantoi, Gilles Boulet, William P. Kustas

Research outputs 2022 to 2026

Global evaporation monitoring from Earth observation thermal infrared satellite missions is historically challenged due to the unavailability of any direct measurements of aerodynamic temperature. State-of-the-art one-source evaporation models use remotely sensed radiometric surface temperature as a substitute for the aerodynamic temperature and apply empirical corrections to accommodate for their inequality. This introduces substantial uncertainty in operational drought mapping over complex landscapes. By employing a non-parametric model, we show that evaporation can be directly retrieved from thermal satellite data without the need of any empirical correction. Independent evaluation of evaporation in a broad spectrum of biome and aridity yielded statistically significant …


Synergistic Efficiency Of Zinc Oxide/Montmorillonite Nanocomposites And A New Derived Saponin In Liquid/Liquid/Solid Interface-Included Systems: Application In Nanotechnology-Assisted Enhanced Oil Recovery, Ahmad Nourinia, Abbas Khaksar Manshad, Seyed Reza Shadizadeh, Jagar A. Ali, Stefan Iglauer, Alireza Keshavarz, Amir H. Mohammadi, Muhammad Ali Jan 2022

Synergistic Efficiency Of Zinc Oxide/Montmorillonite Nanocomposites And A New Derived Saponin In Liquid/Liquid/Solid Interface-Included Systems: Application In Nanotechnology-Assisted Enhanced Oil Recovery, Ahmad Nourinia, Abbas Khaksar Manshad, Seyed Reza Shadizadeh, Jagar A. Ali, Stefan Iglauer, Alireza Keshavarz, Amir H. Mohammadi, Muhammad Ali

Research outputs 2022 to 2026

Oil production faces challenges such as limited oil production from carbonate reservoirs, high oil production costs, and environmental issues. Chemical flooding as an enhanced oil recovery (EOR) method (CEOR) can increase oil production by the use of chemical additives such as surfactants into the reservoirs. Surfactants can increase oil recovery by interfacial tension (IFT) reduction and alteration of the rock wettability from oil-wet to water-wet. The synthesis of chemicals such as synthetic surfactants is usually costly and harmful to the environment. To solve these problems, many researchers have oriented on the use of natural surfactants instead of synthetic ones within …


Role Of Primary Freeboard On Staged Combustion Of Hardwood Pellets In A Fixed Bed Combustor, Awais Junejo, Yasir Al-Abdeli, Jacobo Porteiro Jan 2022

Role Of Primary Freeboard On Staged Combustion Of Hardwood Pellets In A Fixed Bed Combustor, Awais Junejo, Yasir Al-Abdeli, Jacobo Porteiro

Research outputs 2022 to 2026

In staged fixed bed biomass combustion, primary air is supplied beneath the fuel bed with secondary air then provided above in the freeboard region. For fixed bed configurations, the freeboard is further divided into a primary freeboard length (LI), which is upstream of the secondary air and a secondary freeboard length (LII), measured from the secondary air all the way to the exhaust port. Despite extensive research into fixed bed configurations, no work has been successfully completed that resolves the effects of changing LI on fuel conversion, both in the fuel bed and within the freeboard of batch-type biomass combustors. …


Study Of Electric Vehicle Smart Charging And Energy Management For Vehicle-Grid Integration Systems, Zhouquan Wu Jan 2022

Study Of Electric Vehicle Smart Charging And Energy Management For Vehicle-Grid Integration Systems, Zhouquan Wu

Dissertations, Master's Theses and Master's Reports

The emerging need of building an efficient Electric Vehicle (EV) charging infrastructure requires the investigation of all aspects of Vehicle-Grid Integration (VGI). This dissertation studies the optimal EV charging control and energy management of VGI system to address the economic benefits of EV charging customers and operation stability of distribution power grids. First of all, a centralized EV charging control method is developed under the transactive energy environment to minimize the EV charging cost and avoid the distribution power grid overloading. The quadratic programming is used to obtain optimized charging control actions. Case studies with hundreds of EVs are conducted …


Molecular Modeling Of High-Performance Thermoset Polymer Matrix Composites For Aerospace Applications, Prathamesh P. Deshpande Jan 2022

Molecular Modeling Of High-Performance Thermoset Polymer Matrix Composites For Aerospace Applications, Prathamesh P. Deshpande

Dissertations, Master's Theses and Master's Reports

The global efforts from major space agencies to transport humans to Mars will require a novel lightweight and ultra-high strength material for the spacecraft structure. Three decades of research with the carbon nanotubes (CNTs) have proved that the material can be an ideal candidate for the composite reinforcement if certain shortcomings are overcome. Also, the rapid development of the polymer resin industry has introduced a wide range of high-performance resins that show high compatibility with the graphitic surface of the CNTs. This research explores the computational design of these materials and evaluates their efficacy as the next generation of aerospace …


Kinematics And Preliminary Fema P-695 Evaluation Of The Newz-Breakss Steel Boundary Frame With Buckling Restrained Brace Structural Fuses, Alexander M. Baker Jan 2022

Kinematics And Preliminary Fema P-695 Evaluation Of The Newz-Breakss Steel Boundary Frame With Buckling Restrained Brace Structural Fuses, Alexander M. Baker

Dissertations, Master's Theses and Master's Reports

Buckling Restrained Braced Frames (BRBFs) have become a popular seismic force resisting system (SFRS) due to their high ductility and energy dissipation. However, BRBFs are also susceptible to large residual drifts, which can make repair difficult. Efforts to reduce the residual drift of BRBFs typically involve special self-centering braces, or by using a dual system in tandem with the BRBF. This study proposes an alternative approach, in which a self-centering steel rocking frame is used as the boundary frame for the BRBF. The proposed system, called the NewZ-BREAKSS Buckling Restrained Braced Frame (NZ-BRBF) utilizes the recently proposed NewZ-BREAKSS (NZ) boundary …


Towards A Circular Economy: Liquid-Fed Fast Pyrolysis Of Waste Polyolefin Plastics, Daniel G. Kulas Jan 2022

Towards A Circular Economy: Liquid-Fed Fast Pyrolysis Of Waste Polyolefin Plastics, Daniel G. Kulas

Dissertations, Master's Theses and Master's Reports

Plastic usage has quickly grown in recent years as plastics have become an essential part of everyday life. Unfortunately, recycling rates have not matched the increased growth, with the majority of waste plastic landfilled. The strategy of circular economy has been proposed to reuse the waste plastic to create new polymers, thus avoiding both landfilling and the use of virgin raw materials. Achieving a circular economy for plastics requires the development of new technologies capable of recycling plastic waste under a circular economy perspective. In this dissertation, a novel liquid-fed fast pyrolysis process is introduced towards achieving a circular economy. …


Examining Cognitive Empathy Elements Within Ai Chatbots For Healthcare Systems, Lamia Alam Jan 2022

Examining Cognitive Empathy Elements Within Ai Chatbots For Healthcare Systems, Lamia Alam

Dissertations, Master's Theses and Master's Reports

Empathy is an essential part of communication in healthcare. It is a multidimensional concept and the two key dimensions: emotional and cognitive empathy allow clinicians to understand a patient’s situation, reasoning, and feelings clearly (Mercer and Reynolds, 2002). As artificial intelligence (AI) is increasingly being used in healthcare for many routine tasks, accurate diagnoses, and complex treatment plans, it is becoming more crucial to incorporate clinical empathy into patient-faced AI systems. Unless patients perceive that the AI is understanding their situation, the communication between patient and AI may not sustain efficiently. AI may not really exhibit any emotional empathy at …


Development Of Advanced Models For Pre-Ignition Prediction In Gas Engines And Analytical Model For Wallfilm Evaporation, Ankith Ullal Jan 2022

Development Of Advanced Models For Pre-Ignition Prediction In Gas Engines And Analytical Model For Wallfilm Evaporation, Ankith Ullal

Dissertations, Master's Theses and Master's Reports

Ever-changing regulations aimed at improving efficiency and reducing harmful emissions have resulted in many power-generation device (engine) manufacturers to adopt new strategies. Computer simulation of these new strategies of power generation requires more accurate and higher fidelity modelling tools. In the present study, two such models are developed. The first model deals with pre-ignition phenomena driven by lubricant (lube) oil in natural gas engines and the second model is relevant to prediction of wallfilm evaporation by employing analytical solutions to transport governing equations for boundary layers.

Pre-ignition in engines has been the subject of current research with the advent of …


Molecular Modeling Of High-Performance Polymers, Sagar Umesh Patil Jan 2022

Molecular Modeling Of High-Performance Polymers, Sagar Umesh Patil

Dissertations, Master's Theses and Master's Reports

High-performance polymers are extensively used in the aerospace and aeronautics industries due to their low density, high specific strength, and high specific stiffness. These properties along with better infiltration with reinforcements [carbon nanotubes (CNTs), glass, etc.] capability make them an excellent candidate to fabricate Polymer Matrix Composites (PMCs) tailored for specific applications. The applications range from products used daily to deep space exploration. These materials are subjected to varying temperatures and pressures during fabrication and in service. Therefore, the evolution of their intrinsic properties needs to be studied and their ability to sustain extreme environmental conditions in outer space needs …


On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker Jan 2022

On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker

Dissertations, Master's Theses and Master's Reports

Arctic acoustics have been of concern in recent years for the US navy. First-year ice is now the prevalent factor in ice coverage in the Arctic, which changes the previously understood acoustic properties. Due to the ice melting each year, anthropogenic sources in the Arctic region are more common: military exercises, shipping, and tourism. For the navy, it is of interest to detect, classify, localize, and track these sources to have situational awareness of these surroundings. Because the sources are on-water or on-ice, acoustic radiation propagates at a longer distance and so acoustics are the method by which the sources …


Partially Stratified Combustion Of Natural Gas For Spark Ignition Engines, Philip S. Zoldak Jan 2022

Partially Stratified Combustion Of Natural Gas For Spark Ignition Engines, Philip S. Zoldak

Dissertations, Master's Theses and Master's Reports

In this work, the advantages of partially stratified direct injection natural gas versus premixed port-fueled injection natural gas spark ignited engines has been studied. The volumetric efficiency, ratio of specific heats and turbulent kinetic energy was found to be higher with direct injection versus port-fueled injection thus improving thermal efficiency. A background study of optical chamber experimental data was performed to develop an understanding on the effect of pressure ratio on direct injection of methane under both fully-expanded (sub-sonic) and under-expanded (super-sonic) conditions. Under-expanded jets had a noticeable advantage in terms of turbulent kinetic energy, which led to enhanced air …