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Full-Text Articles in Engineering

Smart City Management Using Machine Learning Techniques, Mostafa Zaman Jan 2022

Smart City Management Using Machine Learning Techniques, Mostafa Zaman

Theses and Dissertations

In response to the growing urban population, "smart cities" are designed to improve people's quality of life by implementing cutting-edge technologies. The concept of a "smart city" refers to an effort to enhance a city's residents' economic and environmental well-being via implementing a centralized management system. With the use of sensors and actuators, smart cities can collect massive amounts of data, which can improve people's quality of life and design cities' services. Although smart cities contain vast amounts of data, only a percentage is used due to the noise and variety of the data sources. Information and communication technology (ICT) …


Understanding Structure/Process-Property Relationships To Optimize Development Lifecycle In Yttria-Stabilized Zirconia Aerogels For Thermal Management, Rebecca C. Walker Jan 2022

Understanding Structure/Process-Property Relationships To Optimize Development Lifecycle In Yttria-Stabilized Zirconia Aerogels For Thermal Management, Rebecca C. Walker

Theses and Dissertations

Aerogels are mesoporous materials with unique properties, including high specific surface area, high porosity, low thermal conductivity, and low density, increasing these materials’ effectiveness in applications such as catalyst supports, sorption media, and electrodes in solid oxide fuel cells. Zirconia (ZrO2) aerogels have special interest for high-temperature applications due to the high melting point of ZrO2 (2715°C) and stability between 600°C and 1000°C, where other aerogel systems often begin to sinter and densify. These properties and unique pore structure make zirconia aerogels advantageous as thermal management systems, especially in aeronautics and aerospace applications. However, to be effective …


Influence Of Annealing And Compaction On Enhancing The Temperature And Strain Sensitivities Of Multi-Walled Carbon Nanotube (Mwcnt) Films, Rufaydah Hassan Jan 2022

Influence Of Annealing And Compaction On Enhancing The Temperature And Strain Sensitivities Of Multi-Walled Carbon Nanotube (Mwcnt) Films, Rufaydah Hassan

Theses and Dissertations

Carbon nanotubes (CNTs) possess superior thermal, electrical, and mechanical properties. When CNTs undergo particular fabrication procedures, they transform from a nanoscale form into macroscopic thin sheets referred to as buckypapers (BPs). The main idea behind using BP is to facilitate the handling of CNTs without losing their exceptional properties. Additionally, BPs showed potential for being the used material in strain and temperature applications thanks to their thermal stability, flexibility, high sensitivity, and the ability to conform to any complex structure.

In the current study, the multi-walled carbon nanotube (MWCNT) thin films were prepared using the vacuum filtration technique. Following the …


Stability Analysis Of Dc Microgrid With Constant Power Load, Sarah Ansari Dec 2021

Stability Analysis Of Dc Microgrid With Constant Power Load, Sarah Ansari

Theses and Dissertations

Development towards sustainability has led to an increase in the integration of various distributed generation (DG) units like renewable sources of energy, energy storage systems (ESS). In order to counteract the challenges, caused due to integration of DG units into conventional power systems, the concept of DC microgrid (DCMG) has been introduced. DCMGs have power converters that are present on the source side and load side of the DCMGs. The power converters at the load side when tightly regulated behave as constant power loads (CPLs). There are stability issues pertaining to the inherent non-linear characteristic of the ideal CPLs because …


Energy Planning Model Design For Forecasting The Final Energy Consumption Using Artificial Neural Networks, Haidy Eissa Dec 2021

Energy Planning Model Design For Forecasting The Final Energy Consumption Using Artificial Neural Networks, Haidy Eissa

Theses and Dissertations

“Energy Trilemma” has recently received an increasing concern among policy makers. The trilemma conceptual framework is based on three main dimensions: environmental sustainability, energy equity, and energy security. Energy security reflects a nation’s capability to meet current and future energy demand. Rational energy planning is thus a fundamental aspect to articulate energy policies. The energy system is huge and complex, accordingly in order to guarantee the availability of energy supply, it is necessary to implement strategies on the consumption side. Energy modeling is a tool that helps policy makers and researchers understand the fluctuations in the energy system. Over the …


Sustainable Wastewater Treatment Technology For Rural Communities, Yousra Ahmed Dec 2021

Sustainable Wastewater Treatment Technology For Rural Communities, Yousra Ahmed

Theses and Dissertations

Egypt is considered the country with the largest population in the Middle East Region. It is also expected to have the most significant population increase. The main objective of the present research was to develop a sustainable and effective wastewater treatment technology based on locally available materials such as sand and fabric in the treatment process. From the results obtained from the different experimental runs, it can be concluded that the use of fabric-aided sand filters achieves significant removal efficiency, especially in terms of COD and TSS. The results indicated the technical feasibility of utilizing different fabric materials with nylon …


Machine Learning Based Critical Resource Allocation In Mixed-Traffic Cellular Networks, Mohamed Nomeir Dec 2021

Machine Learning Based Critical Resource Allocation In Mixed-Traffic Cellular Networks, Mohamed Nomeir

Theses and Dissertations

The proliferation of cellular networks over the past two decades has encouraged the expansion of their use in many modern applications. These applications involve the use of data traffic of different quality of service (QoS) requirements. Some of these requirements are quite stringent such as in the case of critical Internet of Things (IoT) health care, military and homeland security applications. This situation resulted in imposing a variety of resource allocation requirements on the cellular network operation in a simultaneous manner.

In this thesis, we consider the challenging problem of mixed-traffic resource allocation, or scheduling, in cellular networks. We focus …


Framework For Enhanced Applicability Of The Egyptian Public Procurement Law To International Administrative Construction Contracts, Amr Abu Helw Dec 2021

Framework For Enhanced Applicability Of The Egyptian Public Procurement Law To International Administrative Construction Contracts, Amr Abu Helw

Theses and Dissertations

Local governments and public authorities conclude contracts for the purpose of acquisition of goods, delivery of services and construction of public facilities like bridges, infrastructures and public buildings. A public contract is an agreement to perform particular tasks financed by government funds to the benefit of the whole community. Private entities and corporations are subject to stricter standards in their dealings with the government than in private transactions. Conversely, the government must deal fairly and equitably with those who it contracted with to achieve successful implementation of the projects. On October 3, 2018, a new Egyptian public procurement law, namely, …


Investigation Of Lithium-Ion Battery Electrode Fabrication Through A Predictive Particle-Scale Model Validated By Experiments, Mojdeh Nikpour Dec 2021

Investigation Of Lithium-Ion Battery Electrode Fabrication Through A Predictive Particle-Scale Model Validated By Experiments, Mojdeh Nikpour

Theses and Dissertations

Next-generation batteries with improved microstructure and performance are on their way to meet the market demands for high-energy and power storage systems. Among different types of batteries, Li-ion batteries remain the best choice for their high energy density and long lifetime. There is a constant but slow improvement in Li-ion batteries by developing new materials and fabrication techniques. However, further improvements are still needed to meet government and industry goals for cost, cycling performance, and cell lifetime. A fundamental understanding of particle-level interactions can shed light on designing new porous electrodes for high-performance batteries. This is a complex problem because …


Design And Analysis Of Flexible Insulated Pavement For Cold Region Applications, Zhuang Zhuo Dec 2021

Design And Analysis Of Flexible Insulated Pavement For Cold Region Applications, Zhuang Zhuo

Theses and Dissertations

Pavements in cold regions suffer from additional deterioration due to the influences of extreme climate on frost-susceptible subgrade layers. To address this problem, one efficient strategy is to add a thermal insulating layer above the frost-susceptible layer. This study aims to evaluate the insulating effects of four materials: XPS boards, tire chips, foamed glass aggregates, and foamed concrete. Large-scale insulated pavement boxes (1.2m×1.2m×0.8m) were constructed to compare the thermal performance of different materials. The thermal performance of each box was evaluated and graded based on indicators related to the short-term temperature decrease and long-term temperature variation.

Experimental results show that …


A Visually Realistic Simulator For Autonomous Evtol Aircraft, Seth M. Nielsen Dec 2021

A Visually Realistic Simulator For Autonomous Evtol Aircraft, Seth M. Nielsen

Theses and Dissertations

Electrically powered vertical takeoff and landing (eVTOL) aircraft could provide a new mode of air transportation of people and cargo that is low-cost, on-demand, and able to reach more areas than is possible with current technology. They have the unique ability to takeoff and land in congested spaces yet efficiently travel long distances which makes them a promising technology for applications such as rapid medical assistance, automated package delivery, or human transportation. This type of aircraft has only recently become a possibility, owing to advancements in battery technology, computing power, and sensor technologies, and thus support for eVTOLs is lacking …


Laser Forming Of Compliant Mechanisms And Flat-Foldable Furniture, Daniel Calvin Ames Dec 2021

Laser Forming Of Compliant Mechanisms And Flat-Foldable Furniture, Daniel Calvin Ames

Theses and Dissertations

Compliant mechanisms are useful for improving existing machines and creating new ones that were not previously possible. They also help us to think of new methods and technologies needed to both improve existing systems as well as manufacture systems that have not been done before. The purpose of this thesis is to show novel implementations of compliant mechanisms into folding systems, and to show new methods for fabricating such mechanisms with nontraditional materials and on difficult scales. Folding systems are shown in furniture applications with chairs, stools, and childcare furniture applications as results of research into how such structures could …


Prediction Equations To Determine Induced Force On Reinforcing Elements Due To Laterally Loaded Piles Behind Mse Wall And Lateral Load Test On Dense Sand, Pedro David Garcia Montesinos Dec 2021

Prediction Equations To Determine Induced Force On Reinforcing Elements Due To Laterally Loaded Piles Behind Mse Wall And Lateral Load Test On Dense Sand, Pedro David Garcia Montesinos

Theses and Dissertations

Researchers performed 35 full-scale lateral load tests on piles driven within the reinforcement zone of a mechanically stabilized earth wall (MSE wall). Data defining the induced tensile force on the reinforcements during lateral pile loading was used to develop multi-linear regression equations to predict the induced tensile force. Equations were developed by previous researchers that did not consider the diameter of the pile, the fixed head condition, relative compaction, or cyclic loading. The purpose of this research was to include this tensile force data and develop prediction equations that considered these variables. Additionally, a full-scale lateral load test was performed …


Advancing Cell-Free Protein Synthesis Systems For On-Demand Next-Generation Protein Therapeutics And Clinical Diagnostics, Emily Ann Long Zhao Dec 2021

Advancing Cell-Free Protein Synthesis Systems For On-Demand Next-Generation Protein Therapeutics And Clinical Diagnostics, Emily Ann Long Zhao

Theses and Dissertations

Recombinant proteins have many medical and industrial applications, but their use is complicated by commercial production and stability constraints. These issues are particularly challenging for recombinant proteins used in pharmaceutical therapeutics and clinical diagnostics. Expensive production and distribution limit the accessibility of therapeutics and diagnostics especially in the developing world. Additionally, clinical use of recombinant proteins face further challenges within biological systems including biological degradation and immunogenicity. To increase the accessibility of recombinant proteins, the cost and inefficiencies of protein manufacturing and distribution need to be significantly reduced. A powerful tool to aid in this endeavor is cell-free protein synthesis …


Identifying And Evaluating Common Subgenres In Asymmetric Virtual Reality Games, Miah Dawes Dec 2021

Identifying And Evaluating Common Subgenres In Asymmetric Virtual Reality Games, Miah Dawes

Theses and Dissertations

Recent years have seen a significant growth in what designers and players call asymmetric virtual reality (AVR) games. This dissertation creates a framework that defines the relevant characteristics of AVR as a genre and describes five common genres of AVR games, including David(s) and Goliath, Hide and Seek, Perspective Puzzle, Order Simulation, and Lifeline. The core features of each subgenre are expounded. These subgenres are then evaluated using design workshops to observe novice game designs use these subgenres in their game design process. An analysis of the workshops found that the AVR subgenre framework may benefit novice game designers in …


A Geometric Approach To Multiple Target Tracking Using Lie Groups, Mark E. Petersen Dec 2021

A Geometric Approach To Multiple Target Tracking Using Lie Groups, Mark E. Petersen

Theses and Dissertations

Multiple target tracking (MTT) is the process of localizing targets in an environment using sensors that perceive the environment. MTT has many applications such as wildlife monitoring, air traffic monitoring, and surveillance. These applications motivate further research in the different challenging aspects of MTT. One of these challenges that we will focus on in this dissertation is constructing a high fidelity target model. A common approach to target modeling is to use linear models or other simplified models that do not properly describe the target's pose (position and orientation), motion, and uncertainty. These simplified models are typically used because they …


Modeling The Effects Of Parameter Changes On Heating And Pressure At The Weld Interface And Joint Strength In Friction Bit Joining, Adam Hartly Wagner Dec 2021

Modeling The Effects Of Parameter Changes On Heating And Pressure At The Weld Interface And Joint Strength In Friction Bit Joining, Adam Hartly Wagner

Theses and Dissertations

Joining of dissimilar metals is a process that is of interest in many fields, especially the automotive industry where lightweighting of the body structure is important. However, creating strong joints between dissimilar metals can be challenging. Friction bit joining (FBJ) is a solid-state method that uses a consumable bit to create a strong joint between dissimilar metals such as aluminum and steel. The purpose of this research is to gain understanding of how adjusting FBJ parameters affects the heating and pressure at the weld interface using a modeling approach, in order to better understand the bonding process. The questions guiding …


The Impact Of Inkjet Parameters And Environmental Conditions In Binder Jetting Additive Manufacturing, Trenton Miles Colton Dec 2021

The Impact Of Inkjet Parameters And Environmental Conditions In Binder Jetting Additive Manufacturing, Trenton Miles Colton

Theses and Dissertations

Binder jetting is an additive manufacturing process in which a part is fabricated layer-by-layer using inkjet technology to selectively dispense binder into powder layers in a designated area. The approach gives this process significant advantages over other additive manufacturing processes such as lower cost, capability to print in a wide range of materials, and little to no heat applied. Although binder jetting has many advantages and has been successful implemented in various industries its overall rate of adoption is slow compared to other processes. This is largely due to poor mechanical properties and consistency in printing which stems from a …


Spline-Based Contact: Algorithms And Applications, Pulama Bhattacharya Dec 2021

Spline-Based Contact: Algorithms And Applications, Pulama Bhattacharya

Theses and Dissertations

Contact is one of the most challenging nonlinearities to solve in solid mechanics. In traditional linear finite element analysis, the contact surface is only C^0 continuous, as a result, the normal to the contact surface is not continuous. The normal contact force is directed along the normal in the direction of the contact surface, and therefore, the contact force is discontinuous. This issue is tackled in linear finite element analysis using various surface smoothing techniques, however, a better solution is to use isogeometric analysis where the solution space is spanned by smooth spline basis functions. Unfortunately, spline-based isogeometric contact analysis …


A Data-Driven Approach For The Investigation Of Microstructural Effects On The Effective Piezoelectric Responses Of Additively Manufactured Triply Periodic Bi-Continuous Piezocomposite, Wenhua Yang Dec 2021

A Data-Driven Approach For The Investigation Of Microstructural Effects On The Effective Piezoelectric Responses Of Additively Manufactured Triply Periodic Bi-Continuous Piezocomposite, Wenhua Yang

Theses and Dissertations

A two-scale model consisting of ceramic grain scale and composite scale are developed to systematically evaluate the effects of microstructures (e.g., residual pores, grain size, texture) and geometry on the piezoelectric responses of the polarized triply periodic bi-continuous (TPC) piezocomposites. These TPC piezocomposites were fabricated by a recently developed additive manufacturing (AM) process named suspension-enclosing projection-stereolithography (SEPS) under different process conditions. In the model, the Fourier spectral iterative perturbation method (FSIPM) and the finite element method will be adopted for the calculation at the grain and composite scale, respectively. On the grain scale, a DL approach based on stacked generative …


A Study Of The Effect Of Load And Displacement Control Strategies On Joint Strength In Friction Bit Joining Of Ga Dp 1180 Steel And Aa 7085-T71, Taylor George Berg Dec 2021

A Study Of The Effect Of Load And Displacement Control Strategies On Joint Strength In Friction Bit Joining Of Ga Dp 1180 Steel And Aa 7085-T71, Taylor George Berg

Theses and Dissertations

Friction Bit Joining (FBJ) is a new technology that can be used to join dissimilar materials together. This ability makes it a good candidate for creating lightweight structures for the automotive industry by combining lightweight materials such as aluminum to stronger materials like advanced high-strength steels. The automotive industry is putting significant effort into interest in reducing vehicle structure weight to increase fuel efficiency and reduce greenhouse gas emissions. Joining of dissimilar materials is a challenge they face in the light weighting the body of the vehicle. The purpose of the current research is to employ FBJ in the joining …


The Development Of A Finite Element Model For Ballistic Impact Predictions, Richard Allen Perkins Dec 2021

The Development Of A Finite Element Model For Ballistic Impact Predictions, Richard Allen Perkins

Theses and Dissertations

Concrete is a widely used product and is an important application throughout industry due to its inexpensive cost and wide range of applications. This work focuses on understanding the behavior of high strength concrete in high strain rate ballistic impact loading scenarios. A finite element analysis was created with the implementation of the Concrete Damage and Plasticity Model 2 (CDPM2) to represent the material behavior. The model’s parameters were calibrated to existing literature and the results were analyzed by a comparison of the impact velocity to residual velocity and a qualitative assessment of the impact crater. The model captured the …


Effects Of The Inclusion Of Rice Hull Derived Bio-Oil On Wood Pellet Production, Tyler E. Lowe Dec 2021

Effects Of The Inclusion Of Rice Hull Derived Bio-Oil On Wood Pellet Production, Tyler E. Lowe

Theses and Dissertations

Wood pellet production has become an advancing industry for the sake of reducing greenhouse emissions into the atmosphere especially, in European Union countries. Researchers and industry executives seek new methods and materials to improve the pelletization process. Rice hulls or husks has the potential to aid in wood pelletization as they possess high calorific values. This study focuses on using rice hull derived bio-oil from pyrolysis, which will also decrease ash content, as an additive to aid in the wood pelletization process. Using two groups of rice hull derived bio-oil as an additive in wood pelletization: Group 1 uses heavy …


Deep Multi-Modal U-Net Fusion Methodology Of Infrared And Ultrasonic Images For Porosity Detection In Additive Manufacturing, Christian E. Zamiela Dec 2021

Deep Multi-Modal U-Net Fusion Methodology Of Infrared And Ultrasonic Images For Porosity Detection In Additive Manufacturing, Christian E. Zamiela

Theses and Dissertations

We developed a deep fusion methodology of non-destructive (NDT) in-situ infrared and ex- situ ultrasonic images for localization of porosity detection without compromising the integrity of printed components that aims to improve the Laser-based additive manufacturing (LBAM) process. A core challenge with LBAM is that lack of fusion between successive layers of printed metal can lead to porosity and abnormalities in the printed component. We developed a sensor fusion U-Net methodology that fills the gap in fusing in-situ thermal images with ex-situ ultrasonic images by employing a U-Net Convolutional Neural Network (CNN) for feature extraction and two-dimensional object localization. We …


Evaluation Of Hyperspectral Band Selection Techniques For Real-Time Applications, Samantha Butler Dec 2021

Evaluation Of Hyperspectral Band Selection Techniques For Real-Time Applications, Samantha Butler

Theses and Dissertations

Processing hyperspectral image data can be computationally expensive and difficult to employ for real-time applications due to its extensive spatial and spectral information. Further, applications in which computational resources may be limited can be hindered by the volume of data that is common with airborne hyperspectral image data. This paper proposes utilizing band selection to down-select the number of spectral bands to consider for a given classification task such that classification can be done at the edge. Specifically, we consider the following state of the art band selection techniques: Fast Volume-Gradient-based Band Selection (VGBS), Improved Sparse Subspace Clustering (ISSC), Maximum-Variance …


Development Of A Three Degree-Of-Freedom Control Simulation For A Group 3 Large Unmanned Aircraft System, Majka Anna Wilczynski Dec 2021

Development Of A Three Degree-Of-Freedom Control Simulation For A Group 3 Large Unmanned Aircraft System, Majka Anna Wilczynski

Theses and Dissertations

Aircraft modeling and simulation has become increasingly important in the aviation world. Simulations allow for safer and more economical training prior to flight testing. In this project, a three degree-of-freedom control simulation coded in a MATLAB environment is used to assess and simulate the dynamic stability of group three unmanned aircraft system. By calculating, evaluating, and simulating the static and dynamic stability derivatives of the aircraft, this project will allow for the estimation of the handling qualities of an unmanned aircraft system. This can help mitigate risks that come along with altering the mass and aerodynamic properties of an aircraft, …


Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates Dec 2021

Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates

Theses and Dissertations

This study produced cross-laminated timber panels at a range of four lamina thickness (5/8, 1, 1 1/8, and 1 1/4 inch) and three bonding pressures (50, 125, 200 psi), producing a total of 12 panels for mechanical testing. The goal of this study is to observe how the thickness and pressure trends affect the mechanical properties of CLT. Tests include flatwise bending, flatwise shear, internal-bond, and delamination. Results showed that bending MOE decreases as the panel thickness increases while bonding pressure had no significance. Bending MOR was less significant for the thickness and more significant for pressure compared to the …


A Longitudinal Analysis Of Pathways To Computing Careers: Defining Broadening Participation In Computing (Bpc) Success With A Rearview Lens, Mercy Jaiyeola Dec 2021

A Longitudinal Analysis Of Pathways To Computing Careers: Defining Broadening Participation In Computing (Bpc) Success With A Rearview Lens, Mercy Jaiyeola

Theses and Dissertations

Efforts to increase the participation of groups historically underrepresented in computing studies, and in the computing workforce, are well documented. It is a national effort with funding from a variety of sources being allocated to research in broadening participation in computing (BPC). Many of the BPC efforts are funded by the National Science Foundation (NSF) but as existing literature shows, the growth in representation of traditionally underrepresented minorities and women is not commensurate to the efforts and resources that have been directed toward this aim.

Instead of attempting to tackle the barriers to increasing representation, this dissertation research tackles the …


3d Shape Estimation Of Negative Obstacles Using Lidar Point Cloud Data, Viswadeep Lebakula Dec 2021

3d Shape Estimation Of Negative Obstacles Using Lidar Point Cloud Data, Viswadeep Lebakula

Theses and Dissertations

Obstacle detection and avoidance plays a crucial role in the autonomous navigation of unmanned ground vehicles (UGV). Information about the obstacles decreases as the distance between the UGV and obstacles increases. However, this information decreases much more rapidly for negative obstacles than for positive obstacles. UGV navigation becomes more challenging in off-road environments due to the higher probability of finding negative obstacles (e.g., potholes, ditches, trenches, etc.) compared with on-road environments. One approach to solve this problem is to avoid the candidate path with a negative obstacle, but in off-road environments avoiding negative obstacles in all situations is not possible. …


Modeling The Ballistic Limit Of Fragment Simulating Projectiles Impacting A36 Mild Steel Spaced Armor Configurations, Daniel H. Rios-Estremera Dec 2021

Modeling The Ballistic Limit Of Fragment Simulating Projectiles Impacting A36 Mild Steel Spaced Armor Configurations, Daniel H. Rios-Estremera

Theses and Dissertations

Terminal ballistics study multivariate behavior and aftermath of projectile and target interactions. Tests and models are often based on monolithic armors, however, layered and spaced armors are common in real world applications. Such configurations add complexities that require research to understand their effects on terminal ballistics. The ballistic limit velocity (V50) represents the speed where armor perforation probability is 50%. It is used for quantitative comparison of protection capabilities for different armors. This research studied the V50 of spaced and layered A36 steel armors against fragment simulating projectiles (FSPs). Four methods for estimating armor V50 were evaluated and compared to …