Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, 2023 University of Maine
Efficient Sintering Of Lunar Soil Using Concentrated Sunlight, Diprajit Biswas
Electronic Theses and Dissertations
Construction material is one crucial need for long-term habitation on the moon. When concentrated for high heat flux, solar radiation can heat lunar soil or regolith until it sinters at temperatures above 900°C. The solid, sintered soil simulant can be used as construction material. This work explores the conditions leading to effective lunar soil sintering for both direct and indirect irradiated sintering. Lunar soil simulants were sintered using concentrated light from a xenon-arc lamp with varying heat flux intensity. During direct sintering of LHS-1, a sintering range of 860°C-1140°C corresponding to a peak heat flux of 105-120 kW/m2 was identified …
Mechanics And Mechanisms Of Fracture For An Eastern Spruce Subject To Transverse Loading Using Acoustic Emission, 2023 The University of Maine
Mechanics And Mechanisms Of Fracture For An Eastern Spruce Subject To Transverse Loading Using Acoustic Emission, Parinaz Belalpour Dastjerdi
Electronic Theses and Dissertations
Due to its excellent structural qualities and accessibility, wood is among the most often utilized structural materials. Despite its ubiquity, wood poses numerous challenges. It is heterogeneous and anisotropic. It has a complex hierarchical ultrastructure, and the properties can have wide variation within a species, and indeed within an individual tree. This work aims to improve our understanding of the strength and fracture behavior of spruce-pine-fir (south) (SPFs), particularly in cross-grain direction. This study’s primary goal is to examine the relationship between crack propagation and cross grain morphology under the following loading configurations: compact tension, compression, and rolling shear. The …
Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, 2023 University of Nebraska-Lincoln
Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system …
Comparative Analysis On Low Cost Continuous Carbon Fiber Polypropylene Composite Using Compression Molding And Automated Tape Placement, 2023 University of Tennessee, Knoxville
Comparative Analysis On Low Cost Continuous Carbon Fiber Polypropylene Composite Using Compression Molding And Automated Tape Placement, Benjamin U. Schwartz
Masters Theses
Carbon fiber reinforced plastics (CFRP) are widely used throughout the aerospace industry where a weight reduction remains the highest priority with less emphasis on cost. Textile grade carbon fiber (TCF) and other low cost carbon fiber (LCCF) alternatives have recently emerged for use in the automotive market where emissions regulations have pushed automotive manufacturers and research institutions to look for cost effective light weight materials. Fiber reinforced thermoplastics provide an effective solution that align with automotive design including low cost, high processing rates, high impact toughness, unlimited shelf life, and recyclability.
TCF and Zoltek_PX35 fibers are two LCCF aimed at …
Machine Learning-Based Data And Model Driven Bayesian Uncertanity Quantification Of Inverse Problems For Suspended Non-Structural System, 2023 Clemson University
Machine Learning-Based Data And Model Driven Bayesian Uncertanity Quantification Of Inverse Problems For Suspended Non-Structural System, Zhiyuan Qin
All Dissertations
Inverse problems involve extracting the internal structure of a physical system from noisy measurement data. In many fields, the Bayesian inference is used to address the ill-conditioned nature of the inverse problem by incorporating prior information through an initial distribution. In the nonparametric Bayesian framework, surrogate models such as Gaussian Processes or Deep Neural Networks are used as flexible and effective probabilistic modeling tools to overcome the high-dimensional curse and reduce computational costs. In practical systems and computer models, uncertainties can be addressed through parameter calibration, sensitivity analysis, and uncertainty quantification, leading to improved reliability and robustness of decision and …
Correlation Between Laboratory Testing Results And In-Situ Sidewalk Scaling, 2023 University of Massachusetts Amherst
Correlation Between Laboratory Testing Results And In-Situ Sidewalk Scaling, Brian R. Shea
Masters Theses
Scaling tests aim to induce scaling behavior in concrete specimens similar to environmental conditions. The efficacy of laboratory tests’ ability to match environmental conditions is important to be able to evaluate the durability of concrete exposed to freeze-thaw cycles and de-icers. This study attempts to correlate results between two existing scaling test standards, ASTM C672 and the BNQ NQ 2621-900. The correlation is done via scaling evaluation including computer-based photogrammetric analysis, visual ratings, and cumulative mass loss measurements. Then a correlation between the laboratory testing and in-situ sidewalk panel specimens is made via visual ratings.
Beirut Arab University - Faculty Of Engineering - Newsletter Issue 0, 2023 Beirut Arab University
Beirut Arab University - Faculty Of Engineering - Newsletter Issue 0, Faculty Of Engineering, Beirut Arab University
Engineering Newsletters
No abstract provided.
Mechanical Property Of Body-Thoroughly Enhanced Austenitic Stainless Steel And High-Mn Steel By Industry-Applicable 3-Axis Stress-Released Impact, 2023 The University of Western Ontario
Mechanical Property Of Body-Thoroughly Enhanced Austenitic Stainless Steel And High-Mn Steel By Industry-Applicable 3-Axis Stress-Released Impact, Busheng Zhang
Electronic Thesis and Dissertation Repository
As two important austenitic steels, the austenitic stainless steel (SS) and austenitic high-Mn steel have been seeking a decent yield strength to match their versatile exceptional advantages. However, the traditional, severe, and high-strain-rate plastic deformation techniques currently used to strengthen the austenitic steels, are limited by their ability to produce ultrastrong steel, bulk sized steel, and the fracturing risk they pose to the steel, respectively. In this research, we propose an industry-applicable 3-axis stress-released impact process, which addresses the challenges facing the current techniques and successfully prepares the body-thorough ultrastrong and ductile austenitic steels without fracturing risk.
The bulk 316L …
Precious Plastics - Plastic Brick Machine Fabrication, 2023 California Polytechnic State University, San Luis Obispo
Precious Plastics - Plastic Brick Machine Fabrication, Timothy Ukaobasi Kanu, Evi Paraskevi Troulis
Architectural Engineering
The goal of this research is to determine the structural parameters of the recycled plastic polypropylene when molded into bricks resembling CMU blocks. To accomplish this, three mechanisms had to be assembled: the shredder, the injector, and the 1x1 mold. A tensile and compression test were to be performed on the plastic brick, and the values would be used to compare the tensile and compressive strength of PP plastic bricks, as well as their modulus of elasticity and stress vs. Strain performance. These values would be analyzed to determine whether it would be feasible to build an entire plastic wall. …
Atomistic Simulation Studies Of Thin Film Growth And Plastic Deformation In Metals And Metal/Ceramic Nanostructures, 2023 Louisiana State University and Agricultural and Mechanical College
Atomistic Simulation Studies Of Thin Film Growth And Plastic Deformation In Metals And Metal/Ceramic Nanostructures, Reza Namakian
LSU Doctoral Dissertations
Despite the significant improvements in manufacturing and synthesis processes of metals and ceramics in the past decades, there are still areas in which the procedure is still frequently more of an art or skill rather than a science. Therefore, systematic and combined experimental and computational studies are required to facilitate the development of techniques that offer thorough understanding of the events taking place during manufacturing and synthesis processes. With regard to these issues, it is paramount to address microscale characterizations and atomic scale understanding of the events during fabrication processes. One of the focuses of this study is unraveling fundamental …
Freespan Analysis For Subsea Pipeline Integrity Management Strategy, 2023 Universitas Indonesia
Freespan Analysis For Subsea Pipeline Integrity Management Strategy, Nurul Hadi, Muhammad Helmi, Edo Cathaputra, Dedi Priadi, Donanta Dhaneswara
Journal of Materials Exploration and Findings (JMEF)
Abstract. Over a rough seabed or on seabed subject to scour, freespans can occur when contact between a subsea pipeline and the seabed is lost over an acceptable distance. When this exceeds the allowable freespan length, design stresses can be exceeded, and a vortex induced vibration (VIV) response can be initiated, resulting in the risk of fatigue failure. If this is not predicted and controlled properly, it will affect pipeline integrity, leading to expensive rectification and intervention work. Freespan analysis consisted primarily of a screening check in which the as-found freespans from Remotely Operated Vehicle (ROV) or multibeam Side …
Architecture Of Heptagonal Metallo-Macrocycles Via Embedding Metal Nodes Into Its Rigid Backbone, 2023 Department of Physics, Old Dominion University, Norfolk, Virginia 23529, United States
Architecture Of Heptagonal Metallo-Macrocycles Via Embedding Metal Nodes Into Its Rigid Backbone, A.M.Shashika D. Wijerathna, He Zhao, Qiangqiang Dong, Qixia Bai, Zhiyuan Jiang, Jie Yuan, Jun Wang, Mingzhao Chen, Markus Zirnheld, Rockwell T. Li, Yuan Zhang, Yiming Li, Pingshan Wang
College of Sciences Posters
Metal-organic macrocycles have received increasing attention not only due to their versatile applications such as molecular recognition, compounds encapsulation, anti-bacteria and others, but also for their important role in the study of structure-property relationship at nano scale. However, most of the constructions utilize benzene ring as the backbone, which restricts the ligand arm angle in the range of 60, 120 and 180 degrees. Thus, the topologies of most metallo-macrocycles are limited as triangles and hexagons, and explorations of using other backbones with large angles and the construction of metallo-macrocycles with more than six edges are very rare.
In this study, …
Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, 2023 Technological University Dublin
Hdd Dataset: Optimising Retrofitted Insulation For Irish Residential Building Walls, Rakshit D. Muddu, Aimee Byrne, Anthony James Robinson
Datasets
In this study, a thermal-economic analysis was conducted to determine the optimum insulation thickness of retrofitted insulation walls in different regions in Ireland. This was based on the Heating Degree Day method (HDD). This dataset contains optimum insulation thickness, payback period, cost savings and carbon emission for all 25 counties in the Republic of Ireland
Application Of Multi-Scale Computational Techniques To Complex Materials Systems, 2023 University of Kentucky
Application Of Multi-Scale Computational Techniques To Complex Materials Systems, Mujan N. Seif
Theses and Dissertations--Chemical and Materials Engineering
The applications of computational materials science are ever-increasing, connecting fields far beyond traditional subfields in materials science. This dissertation demonstrates the broad scope of multi-scale computational techniques by investigating multiple unrelated complex material systems, namely scandate thermionic cathodes and the metallic foam component of micrometeoroid and orbital debris (MMOD) shielding. Sc-containing "scandate" cathodes have been widely reported to exhibit superior properties compared to previous thermionic cathodes; however, knowledge of their precise operating mechanism remains elusive. Here, quantum mechanical calculations were utilized to map the phase space of stable, highly-faceted and chemically-complex W nanoparticles, accounting for both finite temperature and chemical …
Investigation Of Microstructurally Dependent Mechanical Properties Of Cold Sprayed Copper Using Correlative Microscopy, 2023 University of North Florida
Investigation Of Microstructurally Dependent Mechanical Properties Of Cold Sprayed Copper Using Correlative Microscopy, Quintin Otto
UNF Graduate Theses and Dissertations
This project employs multi-instrument materials characterization to analyze material made with the “Cold Spray” additive manufacturing process. Cold spray is an emerging additive manufacturing technique with unique benefits resulting from its low temperature adhesion process induced by plastic deformation. Metallic powder collides at high speeds creating three dimensional materials and coatings without the need for melting. Copper cold sprayed specimens were analyzed using a series of imaging techniques to characterize the microstructure at varying levels of detail and magnification. Scanning electron microscopy and electron back scattered diffraction were paired with microhardness testing to generate a correlative comparison between microstructure and …
Deep Reinforcement Learning For Approximate Policy Iteration: Convergence Analysis And A Post-Earthquake Disaster Response Case Study, 2023 Missouri University of Science and Technology
Deep Reinforcement Learning For Approximate Policy Iteration: Convergence Analysis And A Post-Earthquake Disaster Response Case Study, Abhijit Gosavi, L. (Lesley) H. Sneed, L. A. Spearing
Engineering Management and Systems Engineering Faculty Research & Creative Works
Approximate Policy Iteration (API) is a Class of Reinforcement Learning (RL) Algorithms that Seek to Solve the Long-Run Discounted Reward Markov Decision Process (MDP), Via the Policy Iteration Paradigm, Without Learning the Transition Model in the Underlying Bellman Equation. Unfortunately, These Algorithms Suffer from a Defect Known as Chattering in Which the Solution (Policy) Delivered in Each Iteration of the Algorithm Oscillates between Improved and Worsened Policies, Leading to Sub-Optimal Behavior. Two Causes for This that Have Been Traced to the Crucial Policy Improvement Step Are: (I) the Inaccuracies in the Policy Improvement Function and (Ii) the Exploration/exploitation Tradeoff Integral …
Investigation Of Fiber Orientation And Mechanical Properties Of Pyrolysis Recycled Carbon-Fiber Reinforced Thermoset Composite, 2023 Purdue University
Investigation Of Fiber Orientation And Mechanical Properties Of Pyrolysis Recycled Carbon-Fiber Reinforced Thermoset Composite, Reva N. Simmons, Harry Lee, Garam Kim
Discovery Undergraduate Interdisciplinary Research Internship
With increasing demand of carbon fiber reinforced fiber thermoset composites, establishing a sustainable cycle for these materials becomes crucial. Pyrolysis is a process of reclaiming carbon fiber from thermoset composites by thermally degrading the polymer at high temperatures allowing the fibers to be extracted. Carbon fiber reclaimed through current pyrolysis processes for thermoset composites typically loses its original shape and orientation, making it difficult to reorganize the fibers. This study investigated the feasibility of maintaining the fiber orientations for continuous fiber reinforced thermoset composite during pyrolysis by stitching the carbon fiber layup to a conformable copper mesh during the manufacturing …
Predicting Dissolution Kinetics Of Tricalcium Silicate Using Deep Learning And Analytical Models, 2023 Missouri University of Science and Technology
Predicting Dissolution Kinetics Of Tricalcium Silicate Using Deep Learning And Analytical Models, Taihao Han, Sai Akshay Ponduru, Arianit Reka, Jie Huang, Gaurav Sant, Aditya Kumar
Electrical and Computer Engineering Faculty Research & Creative Works
The dissolution kinetics of Portland cement is a critical factor in controlling the hydration reaction and improving the performance of concrete. Tricalcium silicate (C3S), the primary phase in Portland cement, is known to have complex dissolution mechanisms that involve multiple reactions and changes to particle surfaces. As a result, current analytical models are unable to accurately predict the dissolution kinetics of C3S in various solvents when it is undersaturated with respect to the solvent. This paper employs the deep forest (DF) model to predict the dissolution rate of C3S in the undersaturated solvent. The …
Predicting Compressive Strength And Hydration Products Of Calcium Aluminate Cement Using Data-Driven Approach, 2023 Missouri University of Science and Technology
Predicting Compressive Strength And Hydration Products Of Calcium Aluminate Cement Using Data-Driven Approach, Sai Akshay Ponduru, Taihao Han, Jie Huang, Aditya Kumar
Electrical and Computer Engineering Faculty Research & Creative Works
Calcium aluminate cement (CAC) has been explored as a sustainable alternative to Portland cement, the most widely used type of cement. However, the hydration reaction and mechanical properties of CAC can be influenced by various factors such as water content, Li2CO3 content, and age. Due to the complex interactions between the precursors in CAC, traditional analytical models have struggled to predict CAC binders' compressive strength and porosity accurately. To overcome this limitation, this study utilizes machine learning (ML) to predict the properties of CAC. The study begins by using thermodynamic simulations to determine the phase assemblages of …
A Deep Learning-Informed Design Scheme For Shear Friction At Concrete-To-Concrete Interface: Recommendations For Inclusion In Aashto Lrfd Guidelines, 2023 Missouri University of Science and Technology
A Deep Learning-Informed Design Scheme For Shear Friction At Concrete-To-Concrete Interface: Recommendations For Inclusion In Aashto Lrfd Guidelines, Tarutal Ghosh Mondal, Nikkolas Edgmond, Lesley Sneed, Genda Chen
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Recent advancements in construction technology have led to high-strength concrete and steel. However, these developments have depreciated the accuracy of the design equations in current provisions, which were based on normal-grade materials. To fill such a research gap, this study presents a novel deep learning-based computation scheme that can replace the current design provisions by virtue of its superior accuracy and reliability. The proposed approach exploits Neural Additive Models (NAMs) in which geometric and material properties associated with a normal weight concrete-to-concrete shear interface are inputted to individual neural network blocks. The outputs of the individual blocks are linearly combined …