Studying The Production Of Nanocelluloses,
2024
Tashkent State Technical University, Tashkent city, Republic of Uzbekistan, Doctoral student, [email protected], https://orcid.org/0009-0006-9785-1988;
Studying The Production Of Nanocelluloses, Shohzodbek Abduvahobovich Rashidov, Elmurod Abduqodirovich Egamberdiev, Sadritdin Maxamatdinovich Turabdjanov
Technical science and innovation
Nanoscience is a broad field that includes nanophysics and nanochemistry. Nanotechnologies are aimed at obtaining nanoparticles with new properties and creating materials and devices based on them. This is one of the modern trends in the development of science in the 21st century.
Based on the study of information about nano-sized materials, the mechanisms of their production and changes in their properties, we will consider the technology for producing nanocellulose from organic substances, i.e. from cellulose. The article describes a technology that examines devices for producing nanocellulose and the principles of their operation, as well as a combined method of …
Analysis Of Wingtip Vortex Structure Generated By Bio-Inspired Winglets,
2024
Embry-Riddle Aeronautical University
Analysis Of Wingtip Vortex Structure Generated By Bio-Inspired Winglets, D'Zahn A. Smith
Doctoral Dissertations and Master's Theses
Bio-inspired winglets were studied with the goal of better understanding the structure of the wingtip vortices they generate. Measurements of the tip vortex were previously carried out using stereoscopic particle image velocimetry (sPIV). The bio-inspired winglet was tested on a rectangular NACA 0012 wing section at a 5-degree angle of attack and at a chord Reynolds number of 900,000. Velocity field measurements were recorded at 0.7 and 2 chord lengths aft of the wing’s trailing edge. Compared to the wing with no attachment and a traditional blended winglet, the bio-inspired winglet’s vortex exhibited significantly less intense flow field properties. These …
Comparative Analysis Of Cutting Forces In Axial-Compliant And Rigid Chamfering Tools,
2024
Tashkent State Technical University, Tashkent city, Republic of Uzbekistan, Researcher, [email protected], https://orcid.org/0009-0001-8263-2620;
Comparative Analysis Of Cutting Forces In Axial-Compliant And Rigid Chamfering Tools, Sultonmurod Bekpulatovich Normatov, Oybek Tuyboyov, Azimjon Axror O'G'Li Pardayev, Alisher G‘Ayratjon Ogli Boratov, Shohjahon Tuxtasin Ogli Abdullayev
Technical science and innovation
This study delves into the analysis of cutting forces in axial-compliant systems, focusing specifically on the comparison between axially spring-compensated 90° conical tools and rigid chamfering tools. The research incorporates a predictive model for chamfer size calculation in the axially spring-compensated tools, verified through experimental tests on representative parts. The study aims to control chamfer size within tolerances by adjusting process conditions and optimizing processing efficiency. By exploring the fundamentals of the chamfering process, this research offers insights into breaking sharp edges on components with positional errors and shape deformations, with a particular emphasis on aero-engine casings. The integration of …
Enhancing Cybersecurity In Wireless Sensor Networks: Machine Learning, Blockchain And Future Perspectives,
2024
University of Southern Mississippi
Enhancing Cybersecurity In Wireless Sensor Networks: Machine Learning, Blockchain And Future Perspectives, Ilemona Solomon Atawodi
Dissertations
Security in the Industrial Internet of Things encounters various security issues but the main issues can be broken down into three core issues: Availability, Integrity, and Confidentiality. Security challenges generally tend to be caused by a failure of the system in one of these areas or cause a failure in one of these areas. Therefore researching scalable solutions to these security issues is prudent to explore methods that could be applied to large-scale industrial IIoT with tens to hundreds of devices as well as small-scale systems on a tiny factory floor comprising of just a few devices. In our research, …
A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion,
2024
University of Arkansas, Fayetteville
A Comprehensive Investigation Of The Influence Of Geometric Structure On The Shape Memory Performance Of Nafion, Jade Thomas
Physics Undergraduate Honors Theses
While perfluorosulfonic acid (PFSA) membranes have primarily been used in fuel cells due to their chemical, thermal, and mechanical stability, one PFSA, Nafion, boasts two unique characteristics: a broad glass transition (~55 °C to 130 °C) and a temperature-persistent electrostatic network. The combination of these two characteristics endows Nafion with exceptional shape memory properties – the ability of a material to morph and transform into pre-programmed shapes when exposed to an external stimulus – with enhanced permanent shape memorization, and a potentially near-infinite number of temporary shape memorization. This study focused on expanding the base of knowledge surrounding Nafion’s shape …
High-Altitude Ballooning And Payload Design,
2024
Murray State University
High-Altitude Ballooning And Payload Design, Matthew Smith
Honors College Theses
The Icarus project began in 2017 where a team performs high-altitude balloon (HAB) launches to conduct atmospheric and payload design research. The project involves sending a data-collecting payload containing recording equipment to high altitudes (~100,000 feet). This paper outlines the Icarus project as well as the efforts to design a payload that will remain stable throughout flight while also protecting the equipment housed within the payload shell. SOLIDWORKS computer-aided design (CAD) software was used to design a unique payload system. The payload parts were manufactured with PLA filament using a Prusa MK4 3D printer. The secondary goal of this thesis …
Numerical Investigation Of Supersonic Flow Over A Wedge By Solving 2d Euler Equations Utilizing The Steger–Warming Flux Vector Splitting (Fvs) Scheme,
2024
Wright State University - Main Campus
Numerical Investigation Of Supersonic Flow Over A Wedge By Solving 2d Euler Equations Utilizing The Steger–Warming Flux Vector Splitting (Fvs) Scheme, Mitch Wolff, Hashim H. Abada, Hussein Awad Kurdi Awad Kurdi Saad
Mechanical and Materials Engineering Faculty Publications
Supersonic flow over a half-angle wedge (θ = 15°) with an upstream Mach number of 2.0 was investigated using 2D Euler equations where sea level conditions were considered. The investigation employed the Steger–Warming flux vector splitting (FVS) method executed in MATLAB 9.13.0 (R2022b) software. The study involved a meticulous comparison between theoretical calculations and numerical results. Particularly, the research emphasized the angle of oblique shock and downstream flow properties. A substantial iteration count of 2000 iteratively refined the outcomes, underscoring the role of advanced computational resources. Validation and comparative assessment were conducted to elucidate the superiority of the Steger–Warming flux …
Rasc-Al Large Scale Lunar Crater Prospector,
2024
Kennesaw State University
Rasc-Al Large Scale Lunar Crater Prospector, Austin Arnold, Coleman Alvarez, Mark Suberu
Senior Design Project For Engineers
The purpose of this project is to design a conceptual layout of a lunar rover capable of exploring craters at the lunar south pole. The rover should be autonomous and capable of self-sustainment for at least one year in extreme cold and darkness. While determining the location and accessibility of water ice and other volatiles within the crater. This document will contain all information related to the team's conceptual design. Including research, component selection, electrical design, and mechanical design.
Lunar Rascals Video: https://www.youtube.com/watch?v=MdcjzVMtzaI
Using Convolutional Neural Networks For Autonomous Drone Navigation,
2024
University of Arkansas, Fayetteville
Using Convolutional Neural Networks For Autonomous Drone Navigation, Joshua Jowers
Industrial Engineering Undergraduate Honors Theses
Unmanned Aerial Vehicles (UAVs), more commonly known as drones, serve various purposes, notably in military applications. Consequently, there arises a need for navigation methods impervious to intercepted signals [1]. Previous research has explored numerous solutions, including machine learning. This paper delves into a specific machine learning approach employing a Convolutional Neural Network (CNN) to discern image locations [2]. It elucidates the conversion of a CNN model between two machine learning libraries and presents results from multiple experiments examining parameters and factors influencing the approach's efficacy. These experiments encompass testing different data sources, image quantities, and processing pipelines to gauge their …
Transfer-Learning-Enhanced Regression Generative Adversarial Networks For Optimal Evtol Takeoff Trajectory Prediction,
2024
Missouri University of Science and Technology
Transfer-Learning-Enhanced Regression Generative Adversarial Networks For Optimal Evtol Takeoff Trajectory Prediction, Shuan Tai Yeh, Xiaosong Du
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Electric vertical takeoff and landing (eVTOL) aircraft represent a crucial aviation technology to transform future transportation systems. The unique characteristics of eVTOL aircraft include reduced noise, low pollutant emission, efficient operating cost, and flexible maneuverability, which in the meantime pose critical challenges to advanced power retention techniques. Thus, optimal takeoff trajectory design is essential due to immense power demands during eVTOL takeoffs. Conventional design optimizations, however, adopt high-fidelity simulation models in an iterative manner resulting in a computationally intensive mechanism. In this work, we implement a surrogate-enabled inverse mapping optimization architecture, i.e., directly predicting optimal designs from design requirements (including …
Rapid Response Satellite Launcher,
2024
Kennesaw State University
Rapid Response Satellite Launcher, Nathan Jones, Joey Cosentino, Jayson Layton, Afek Adar
Senior Design Project For Engineers
Air launch to orbit is a new style or spacecraft where rockets are attached to a large aircraft and released at cruising altitude to then ignite and launch into space. Companies such as Virgin Orbit are using it as a cheap and efficient way to move satellite payloads into lower or upper Earth orbit. These styles of launchers can be designed to be much smaller than ground-launched spacecraft, reducing cost and weight of the launcher in comparison. With many private companies coming into the space and satellite industry, the design and manufacturing of these launchers have become a focus within …
Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments,
2024
University of Texas at El Paso
Analysis Of Additively Manufactured Inconel 718 Combustion Behavior In Promoted Oxygen Environments, Dominic George Dieguez
Open Access Theses & Dissertations
Promoted combustion testing is a vital tool for engineers to establish the combustion and flammability characteristics of materials (metallic or otherwise) in oxygen enriched environments. Historically, much of the established data for metallic promoted combustion has been with regards to materials in their cast and wrought forms. However, with the emergence of additive manufacturing as a preferred method of fabrication, the need exists to evaluate how metals in that form behave. Recent testing has demonstrated that even if a metal or alloy is nominally the same with regards to chemistry, flammability between samples in the wrought form can differ significantly …
Physics-Guided Scan Paths Optimization For Controlled Microstructure In Laser Powder Bed Fusion,
2024
University of Texas at El Paso
Physics-Guided Scan Paths Optimization For Controlled Microstructure In Laser Powder Bed Fusion, Augustine Twumasi
Open Access Theses & Dissertations
Laser Powder Bed Fusion (L-PBF) is a renowned additive manufacturing technique, celebrated for its capability to construct intricate metal components with remarkable precision. However, one of the main challenges with L-PBF is the formation of complex microstructures, which can significantly impact the final material properties. To address this issue, our study proposes a physics-guided and machine-learning-aided approach to optimize scan paths for achieving desired microstructure outcomes, such as the generation of equiaxed grains that enhance material properties. By using phase-field modeling, a physics-based computational method, we gain insights into microstructure evolution. To reduce computational costs, we train a surrogate machine-learning …
Effects Of Process-Induced Defects On The Corrosion Of Additively Manufactured Stainless Steel 304l,
2024
Missouri University of Science and Technology
Effects Of Process-Induced Defects On The Corrosion Of Additively Manufactured Stainless Steel 304l, Leila Saberi, Frank W. Liou, Mehdi Amiri
Mechanical and Aerospace Engineering Faculty Research & Creative Works
This Study Investigates the Impact of Process-Induced Defects Such as Gas Pores, Lack of Fusions, and Surface Roughness on Corrosion Behavior of Stainless Steel 304L (SS304L) Fabricated by Laser Powder Bed Fusion Additive Manufacturing. Specimens Are Printed with Optimized Process Parameters but Selected from Different Locations on the Build Plate. Parallel and Perpendicular Surfaces to the Build Direction Are Investigated and Compared with Corrosion Properties of Wrought SS304L in 5 Wt% NaCl. the Results Reveal Significant Difference in Corrosion Behavior among Specimens Due to Variations in their Defect Features. Pitting Potential, Pit Initiation, and Growth Rates Are Found to Be …
Effect Of Pre-Heating On Residual Stresses And Deformation In Laser-Based Directed Energy Deposition Repair: A Comparative Analysis,
2024
Missouri University of Science and Technology
Effect Of Pre-Heating On Residual Stresses And Deformation In Laser-Based Directed Energy Deposition Repair: A Comparative Analysis, Usman Tariq, Sung Heng Wu, Muhammad Arif Mahmood, Michael M. Woodworth, Frank W. Liou
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Laser-Directed Energy Deposition (DED), a Metal Additive Manufacturing Method, is Renowned for its Role in Repairing Parts, Particularly When Replacement Costs Are Prohibitive. Ensuring that Repaired Parts Avoid Residual Stresses and Deformation is Crucial for Maintaining Functional Integrity. This Study Conducts Experimental and Numerical Analyses on Trapezoidal Shape Repairs, Validating Both the Thermal and Mechanical Models with Experimental Results. Additionally, the Study Presents a Methodology for Creating a Toolpath Applicable to Both the DED Process and Abaqus CAE Software. the Findings Indicate that Employing a Pre-Heating Strategy Can Reduce Residual Stresses by over 70% Compared to No Pre-Heating. However, Pre-Heating …
Characterization And Analysis Of Supersonic Flow Through De Laval Nozzles At Varied Design Conditions,
2024
Embry-Riddle Aeronautical University
Characterization And Analysis Of Supersonic Flow Through De Laval Nozzles At Varied Design Conditions, Sarah Baird
Doctoral Dissertations and Master's Theses
A combined numerical and experimental investigation of supersonic planar nozzles under different design conditions has been conducted. Supersonic planar nozzles are common geometries observed in supersonic wind tunnels and aircraft or rocket engines. For the important role they play in wind tunnel testing and aircraft propulsion, it is important to conduct a thorough numerical and experimental study to characterize their performance at different operating conditions. In this study, a de Laval nozzle was scanned to extract its contours and subsequently modeled to compare analytical and numerical performance expectations under design and off-design conditions. The nozzle was then installed in a …
Blade Design And Validation Of Hydrokinetic Turbine To Harvest Water Current Energy,
2024
University of New Orleans
Blade Design And Validation Of Hydrokinetic Turbine To Harvest Water Current Energy, Setare Sadeqi
LSU New Orleans Theses and Dissertations
The innovative aspect of this research lies in the careful integration of cutting-edge technologies throughout the entire process of designing, fabricating, and testing the carbon fiber propeller for the 3-bladed horizontal axis ocean current turbine (OCT). SolidWorks software played a pivotal role in the initial design phase, enabling a meticulous and precise modeling of the propeller's geometry. The utilization of SolidWorks allowed for a detailed exploration of various design parameters, ensuring that the propeller's structure and form were optimized for performance in ocean current conditions. Moving beyond the realm of virtual design, the choice of carbon fiber as the fabrication …
Investigation On The Effects Of Biofouling On The Boundary Layer,
2024
LSU New Orleans
Investigation On The Effects Of Biofouling On The Boundary Layer, Adam N. Bacon
LSU New Orleans Theses and Dissertations
This study is an investigation of the effect of biofouling on the boundary layer of a flat plate and a NACA 4-digit series foil. Three identical hydrofoils made of resin were placed in the Gulf of Mexico at Grand Isle, Louisiana, and observed and analyzed by marine biologists at the University of New Orleans for their species composition. The resulting biofouling that grew was primarily made up of barnacles and bryozoans. The foils were submerged in an open channel flume at zero incidence and subjected to a series of experiments whose arc-length Reynolds numbers ranged from approximately 13000 to 32000. …
Towing Tank Trials Of Hydrokinetic Turbine Scale Model To Support Marine Energy System Verification,
2024
University of New Orleans
Towing Tank Trials Of Hydrokinetic Turbine Scale Model To Support Marine Energy System Verification, Shahab Rouhi
LSU New Orleans Theses and Dissertations
In response to the escalating demand for sustainable energy solutions and the critical reevaluation of conventional fossil fuels due to environmental concerns, this dissertation embarks on a comprehensive exploration of hydrokinetic energy as a promising alternative. The study delves into the underexplored domain of hydrokinetic energy, leveraging innovative methodologies for effective utilization and harnessing, particularly through the development and investigation of hydrokinetic turbines.
In the realm of hydrokinetic energy conversion, our research has exclusively concentrated on horizontal-axis turbines, distinct from other turbine configurations. Noteworthy is the adaptation of a conventional horizontal-axis wind turbine for water currents, revealing enhanced performance through …
Performance Effects Of Dissociated Hydrogen In Nuclear Thermal Propulsion Engines,
2024
University of Nevada, Las Vegas
Performance Effects Of Dissociated Hydrogen In Nuclear Thermal Propulsion Engines, Richard Adam Gorrell
UNLV Theses, Dissertations, Professional Papers, and Capstones
Nuclear thermal propulsion (NTP) research considers hydrogen dissociation as negligible to design and analysis of propulsion engines. This study reintroduces chemically reacting flow to NTP engine analysis for investigation of the dissociation effect on engine performance. A first-principles approach observes the basic chemical mechanism and reaction within the high-speed, high-temperature NTP flow to baseline expected atomic hydrogen levels and validate equilibrium. A surface reaction study looks into hydrogen absorption through dissociation and its effect on the boundary layer, and bulk flow. For total performance, the resulting dissociated flow is analyzed through nozzle expansion and performance metrics calculated.
All historic reactor …
