Mechanical Engineering Commons^™

A Marine Knowledge System For Ocean Affairs: Integrating Data, Evaluating Usage, And Enabling Sustainable Marine Management, Yu-Jen Pan

Journal of Marine Science and Technology–Taiwan

This study presents the evolution and assessment of the Marine Knowledge Education System (MKES), designed to improve user acceptance among students in professional marine science courses in Taiwan. The MKES leverages real-world maritime cases from the General Coast Guard Administration and is built upon existing technologies like cloud services, social networks, and data analysis tools. The technology acceptance model (TAM) provides the theoretical underpinning for the assessment of user confidence. Data was collected from 190 participants through purposive sampling. Path analysis confirmed all hypothesized relationships within the TAM with statistical significance (p < 0.001). Additionally, paired-sample t-tests revealed a significant increase in student acceptance of the MKES after integrating it into the marine science curriculum. These findings underscore the capacity of the MKES as a digital learning tool to enrich course pedagogy and improve student learning outcomes, thereby offering valuable support in advancing the education of professional marine managers.

Improved Parameters Of Anand Model And Advanced Fea Technique For Low-Cycle Fatigue Life: Finite Element Analysis Models For Pb-Free Solder And Pb Solder In Real Life Ball Gird Ally Package, Hamidreza Nahavandi

Dissertations and Theses

The present study uses the finite element method to evaluate the fatigue life of solder joints of plastic ball grid array packages (PBGA) under thermal-cycling conditions. A Series of precise 3D FE models for solder joints of plastic ball grid array packages is created to improve reliability prediction accuracy. Damage parameters are obtained from the FEA results and used to estimate solder balls’ thermal fatigue life. The Coffin-Manson equation is employed. The predicted thermal fatigue lives are discussed in detail.

Due to marketing and legislative pressures, Pb-free solder is fast becoming a reality in electronic manufacturing. The industry has concluded …

Boosting Steam Tolerance And Electrochemical Performance Of An La0.6Sr0.4Co0.2,Fe0.8O3− Δ-Based Air Electrode For Protonic Ceramic Electrochemical Cells, Lei Wu, Jiqiang Sun, Huiyang Qi, Baofeng Tu, Chunyan Xiong, Fanglin Chen, Peng Qiu

Faculty Publications

La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) is the state-of-the-art air electrode material for solid oxide electrochemical cells using oxide-ion electrolytes, yet its application in proton ceramic electrochemical cells (PCCs) remains limited, mainly attributed to its instability under operating conditions of high temperature and high humidity. To address this issue, coating a PrCoO_3−δ (PCO) catalyst onto the LSCF scaffold has been evaluated in this study. The introduction of the PCO coating not only enhances the LSCF electrode's electrochemical performance but also significantly improves its steam tolerance by preventing direct contact between steam and …

Experimental Study Of Drag Characteristics And Dust Removal Performance Of A Hybrid Wet-Filter Precipitator, Hang Yi, Zifeng Yang, Deqiang Chang, Xinjiao Tian, Jingxian Liu

Mechanical and Materials Engineering Faculty Publications

With their advantages of high dust removal efficiency and low drag characteristics, hybrid wet-filter precipitators have great potential for dust control in coal mines, but the underlying mechanisms are not well understood. In this study, to help fill this knowledge gap, a hybrid wet-filter precipitator consisting of a 40-layer metal filter and a defogger device is designed and a prototype is constructed. Experiments are conducted to investigate its drag characteristics under wind velocities from 0.85 to 5.68 m/s and its dust removal performance under wind velocities of 2 and 4 m/s. On the basis of results with the initial design, …

The Effect Of Gamma-Ray Irradiation On Polymer-Graphene Nanocomposite Interfaces, Sagar Patil, Josh Kemppainen, Travis Wavrunek, Gregory Odegard

Michigan Tech Publications

CNT yarns are used in ultra-high strength composites for use in manned deep-space vehicles. It has been previously demonstrated through experiments that gamma-ray irradiation substantially improves the mechanical performance of these composites. It is unclear how the irradiation affects the mechanical response of the CNT yarn/polymer interface that ultimately leads to these panel-level performance improvements. Physical insight into this process could enable further improvements in the CNT yarn/polymer interface design in the future. The objective of this research is to use molecular dynamics simulation to provide physical insight into the effect of gamma-ray irradiation on the mechanical behavior (interfacial interaction …

A Robust Recurrent Neural Networks-Based Surrogate Model For Thermal History And Melt Pool Characteristics In Directed Energy Deposition, Sung Heng Wu, Usman Tariq, Ranjit Joy, Muhammad Arif Mahmood, Asad Waqar Malik, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In directed energy deposition (DED), accurately controlling and predicting melt pool characteristics is essential for ensuring desired material qualities and geometric accuracies. This paper introduces a robust surrogate model based on recurrent neural network (RNN) architectures—Long Short-Term Memory (LSTM), Bidirectional LSTM (Bi-LSTM), and Gated Recurrent Unit (GRU). Leveraging a time series dataset from multi-physics simulations and a three-factor, three-level experimental design, the model accurately predicts melt pool peak temperatures, lengths, widths, and depths under varying conditions. RNN algorithms, particularly Bi-LSTM, demonstrate high predictive accuracy, with an R-square of 0.983 for melt pool peak temperatures. For melt pool geometry, the GRU-based …

Validation Of Mobile Devices In Arbitrary Locations Against Force Plate Standard For Balance Assessment, German J. Ellsworth

Master's Theses

With balance assessment being essential to the prediction of fall risk and detection and assessment of motor disorders, increasing clinical accessibility to objective balance metrics is essential. Work has been done validating center of mass (COM) acceleration metrics against well regarded force plate center of pressure (COP) position standards for mobile device data acquisition systems, but most research is restricted to devices being close to the COM or strapped in a harness configuration. Through the use of rigid body kinematics and the inverted pendulum model, this study develops novel methodology for calculating COM acceleration using mobile devices in arbitrary positions, …

Design And Implementation Of An Inverted Short Baseline Acoustic Positioning System, Jakob Frabosilio

Master's Theses

This document details the design, implementation, testing, and analysis of an inverted short baseline acoustic positioning system. The system presented here is an above-water, air-based prototype for an underwater acoustic positioning system; it is designed to determine the position of remotely-operated underwater vehicles (ROVs) and autonomous underwater vehicles (AUVs) in the global frame using a method that does not drift over time.

A ground-truth positioning system is constructed using a stacked hexapod platform actuator, which mimics the motion of an AUV and provides the true position of an ultrasonic microphone array. An ultrasonic transmitter sends a pulse of sound towards …

First-Order Comprehensive Adjoint Sensitivity Analysis Methodology For Neural Ordinary Differential Equations: Mathematical Framework And Illustrative Application To The Nordheim–Fuchs Reactor Safety Model, Dan Gabriel Cacuci

Faculty Publications

This work introduces the mathematical framework of the novel “First-Order Comprehensive Adjoint Sensitivity Analysis Methodology for Neural Ordinary Differential Equations” (1st-CASAM-NODE) which yields exact expressions for the first-order sensitivities of NODE decoder responses to the NODE parameters, including encoder initial conditions, while enabling the most efficient computation of these sensitivities. The application of the 1st-CASAM-NODE is illustrated by using the Nordheim–Fuchs reactor dynamics/safety phenomenological model, which is representative of physical systems that would be modeled by NODE while admitting exact analytical solutions for all quantities of interest (hidden states, decoder outputs, sensitivities with respect to all parameters and initial conditions, …

Surrogate-Based Multidisciplinary Optimization For The Takeoff Trajectory Design Of Electric Drones, Samuel Sisk, Xiaosong Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Electric vertical takeoff and landing (eVTOL) aircraft attract attention due to their unique characteristics of reduced noise, moderate pollutant emission, and lowered operating cost. However, the benefits of electric vehicles, including eVTOL aircraft, are critically challenged by the energy density of batteries, which prohibit long-distance tasks and broader applications. Since the takeoff process of eVTOL aircraft demands excessive energy and couples multiple subsystems (such as aerodynamics and propulsion), multidisciplinary analysis and optimization (MDAO) become essential. Conventional MDAO, however, iteratively evaluates high-fidelity simulation models, making the whole process computationally intensive. Surrogates, in lieu of simulation models, empower efficient MDAO with the …

Slo Children’S Museum Music Education Exhibit, Charles Coffen, Madeline Carleton-Sniff, Yael Castillo, Anthony Ramos

Mechanical Engineering

The Children’s Museum in San Luis Obispo is a non-profit facility providing education to young children through interactive exhibits. The proposed project would address a basic introduction to musical theory through mechanical engineering principles. The target audience for this musical art installation would be young children, aged 5-10, who would be regularly interacting with this exhibit, as well as their parents, and the employees of the museum. The installation will educate children in basic musical understanding through interaction while still being engaging enough to hold their attention. This document describes the final concept design and various methods of verification in …

Electrified Membrane For Water Treatment And Resource Recovery: Advancing Multiscale Strategies In Gas-Involving Reactions, Jianan Gao

Dissertations

Multifunctional, modular, and scalable water treatment technologies that operate without chemical additives are crucial for addressing global water pollution challenges. While traditional membrane-based separation processes are crucial for ensuring clean water supplies, they primarily focus on pollutant removal rather than on the upcycling of pollutants into valuable resources. Electrified membrane filtration presents a robust alternative, utilizing minimal or no chemical additives and harnessing electrical power to directly reduce contaminants or produce reactive oxidants or reductants on-site.

This dissertation is dedicated to the development of innovative electrochemically reactive membranes designed to address three major challenges: (1) the engineering of electrocatalysts with …

Collision Dynamics Of Compound Droplets In Microchannels: A Combined Numerical And Data-Driven Study, S M Abdullah Al Mamun

Dissertations

Understanding and predicting the hydrodynamic interactions of micron-scale droplets is crucial in a wide range of industrial and real-life applications, including microfluidics, pharmaceutics, drug delivery, food science, and enhanced oil recovery. These multi-phase and multi-scale phenomena are further complicated by the presence of core droplets of an immiscible fluid within shell droplets, known as compound droplets. The collisions and interactions of droplets in emulsions are influenced by various physical and geometric parameters, leading to distinct rheological and dynamic responses. This research employs numerical methods for a systematic parametric study of both simple and compound droplet pair collisions under confined shear …

Modular Reconfigurable Rotary Style Soft Pneumatic Actuators, Nicholas Pagliocca, Aatish Gupta, Joshua Knospler, Nand K. Singh, Mitja Trkov

Henry M. Rowan College of Engineering Departmental Research

Modular soft robots have the advantage in their ability to be reconfigured and change their morphology on-demand according to a specified task. The actuator design and particularly the inter-unit connectivity strength commonly govern the usability and functionality of these modular robots and their applications. In this paper, we present development of reconfigurable modular rotary soft actuators that allow the construction of highly versatile soft robotic actuators and systems. These pneumatically driven modular actuators are composed of an inner balloon and a flexible arched reinforcement structure to produce a rotary motion. They serve as building blocks which may be combined in …

Effect Of Gas Tungsten Arc Welding Process Variants On The Microstructure And Properties Of Az31b Magnesium Alloy And 304hcu Austenitic Stainless Steel Welds, Srinivasan S

Theses and Dissertations

The automotive and aero sectors seek materials with high specific strength & specific stiffness for enhanced efficiency / emission control. Mg alloys, known for their low density, are used in the as-cast, and wrought forms, depending on the service requirements, and are predominantly used for non-loaded structural parts in varied engineering applications. Welding Mg alloys is of great interest to industry, not only for the fabrication of components but for the repair welding of casting as well. There has been considerable research in the fusion & solid-state welding of Mg alloys. Gas tungsten arc welding (GTAW) has often been preferred …

Identification Of Delamination Defect In Fibre Reinforced Polymer Composite Tapered Plate Based On Vibration Measurement, Venkatesan M

Theses and Dissertations

Fibre-reinforced polymer (FRP) composite plates have been widely used in various engineering applications due to their high strength-to-weight ratio, corrosion resistance, and durability. Despite their many benefits, Delamination is a separation of the layers in composite material and can occur due to various factors such as impact, fatigue, and manufacturing defects. Identifying delamination in composite structures is crucial for ensuring safety and reliability. In this study, model-dependent vibration methods, which are an effective non-destructive technique, were utilised for delamination identification. The primary objective is to investigate the dynamic behaviour of delaminated thickness-tapered plates and develop a reliable methodology for delamination …

Recent Evolution In Thermochemical Transformation Of Municipal Solid Wastes To Alternate Fuels, Tumpa R. Sarker, Lucky Khatun, Bangladesh Agricultural University, Rostom Ali, Shariful Islam, Sagor Chowdhury, Kazi Sakibur Rahman, Nafis Sadique Sayem, Akm S. Rahman

Publications and Research

The management of solid waste poses a worldwide obstacle in the pursuit of a sustainable society. This issue has intensified with the increase in waste production caused by rapid population expansion, industrialization, and urbanization. The continuously growing volume of municipal solid waste, particularly the substantial volume of organic waste, along with improper disposal practices, results in the release of greenhouse gases and other harmful airborne substances which simultaneously causes health risks and socioeconomic concerns. This article examines various waste-to-energy (energy production in the form of heat and electricity) concepts as well as waste-to-materials (various value-added materials including biofuel, biochemical, char, …

Capacitive Sensors With Ultra-Small Capacitance For Smart Measurement And Control Systems, Rustam Baratov, Farrux Jabbor O'G'Li Ko'charov

Chemical Technology, Control and Management

This article discusses methods of low capacitance measurement of capacitive sensors. The results of the study of the amplitude-frequency (AF) and phase-frequency (PF) response of measurement circuits of capacitive sensors for low capacitances measurement, consisting of RC - differentiating elements are presented. The input and output parameters of the differentiating circuit and the complex transfer function are analyzed. The research results show that low capacitances measurement by measuring the rectangular pulses duration is the most effective measurement method.

Endwall Contouring For Lowering The Thermal Load And Augmenting The Turbine Efficiency, Arjun Kozhikkatil Sunil, Tide Porathoor Sunny

Makara Journal of Technology

Endwall contouring having significance in delineating ideal endwalls competent in thermal load depletion is the focus of this study. We have successfully utilized non-axisymmetric contoured endwalls to enhance turbine performance by controlling the secondary flow characteristics in a blade passage through steady-state numerical hydrodynamics. The supreme endwall pattern could lower the gross pressure loss at the design stage and is related to the size of the top-loss location being productively lowered. The selective numerical shape change using multi-objective optimization at the most prominent locations resulted in contoured endwall geometry and a considerable reduction of thermal exchange in the vane passage …

Machine Learning Framework For Predicting Reliability Of Solder Joints, Robert Lee Jones

Dissertations and Theses

This paper presents the techniques and framework to produce an explainable machine learning model for predicting the reliability of solder joints exposed to thermal cycle testing. While machine learning techniques have become prevalent for many engineering and data analysis tasks, the complexity of the model occludes valuable information which can be used to refine the data, tune model parameters, and aid in scientific discovery. By exposing the relationships within the model, users can have greater confidence in the use and employment of it. The purpose of this study is to show how useful relationships can be obtained from a traditional …

On The Effects Of Personalizing Vibrotactile Feedback To Facilitate User Interaction With A Robotic System, Sudip Hazra, Panos S. Shiakolas

Open Initiatives Grant Funded Publications-Archive

Distinguishable vibrotactile feedback can convey information non-verbally and complete the sensory loop when using assistive devices. Feedback can increase acceptance of assistive devices but could require personalization as these devices need to adapt to user capabilities and preferences that may affect the location for inducing feedback. Developing personalized feedback for each user may be ideal, but impractical if demand for these devices increases. In this research, we evaluate the hypothesis that the ability to define, generate, and use personalized feedback is preferred and should be provided. The hypothesis is evaluated using a system capable of capturing and recognizing non-verbal inputs, …

Damage Of Nickel-Coated Glass/Epoxy Foam-Core Composites Induced By Artificial Lightning Strikes, Van-Tho Hoang, Won-Ho Choi, Juhyeong Lee, Chanyeop Park, Jin-Hwe Kweon, Byeong-Su Kwak, Young-Woo Nam

Mechanical and Aerospace Engineering Faculty Publications

In the field of composite materials, many reports have shown that catastrophic structural damage is caused by lightning strikes. In this study, new design concepts were proposed for the lightning-strike protection of nickel-coated glass/epoxy foam-core composites. Instead of using a neat metal mesh, glass fibers were modified with nickel particles via a plating technique to improve their thermal and electrical conductivities. In addition, a thin Invar plate was inserted at the middle of the structure and a foam core was introduced to reduce damage to the structure. Three models with different materials and stacking sequences were used in this study. …

Tendrilbot: Modular Soft Robot With Versatile Radial Grasping And Locomotion Capabilities, Joshua Knospler, Nicholas Pagliocca, Wei Xue, Mitja Trkov

Henry M. Rowan College of Engineering Departmental Research

This paper introduces TendrilBot, a novel modular soft robot designed for versatile manipulation, stiffness modulation, and locomotion tasks. Built upon previously developed modular units, the TendrilBot consists of multiple actuators connected linearly in linear, cylindrical, or helix configurations. Cylindrical configurations (single row or stacked) enable the robot to wrap around objects for grasping and manipulation in a single row or stacked configuration when interconnected with the magnets on sides of the units. Additionally, such configurations further facilitate internal grasping within hollow tubes or objects holding them with its reconfigurable shape. Both wrapping and internal grasping are experimentally validated to demonstrate …

Investigation Of Distributed Additive Manufacturing For 3d Printed Headband Component During Global Supply Chain Disruptions, Elizabeth M. Mamros, Saketh Kantipudi, Matthew C. Eaton, Jinjin Ha, Brad L. Kinsey

Faculty Conference Papers and Presentations

During the COVID-19 global pandemic, a shortage of personal protective equipment (PPE) occurred. Manufacturers of these critical products were unable to keep up with the growing demands as the situation evolved. Most face shields, a common type of PPE, include a headband component to provide the appropriate fit for the user and curvature for the clear face shield attachment. To mitigate this shortage in the local region, the Portsmouth Naval Shipyard (PNSY) generated a computeraided design (CAD) file for the headband component and asked the University of New Hampshire (UNH) to manufacture it with all available 3D printers, including printers …

Evaluation Of Business-Driven Reference Architecture For Big Data Analytics Implementation By Public Sector Organizations In Resource-Constrained Setting: A Case Study Of Uganda, Matendo Didas

Tanzania Journal of Engineering and Technology (TJET)

Big Data Analytics (BDA) is a new area at the nexus of agenda, public sector organizations, and government business. It may satisfy the growing need for trustworthy, cost-effective services in the public sector for better, more informed decision-making processes. BDA has been proposed on the planning schedules of several public sector organizations and the government. Therefore, from the previous work, using Uganda as a case study, specifically the Uganda Bureau of Statistics (UBOS), Ministry of Health (MoH), and Ministry of Education and Sports (MoES), this study aims to evaluate a designed Business-Driven Reference Architecture for Big Data Analytics Implementation (BRABDAI) …

Modeling The Influence Of Internal Factors On Vehicular Mobility Performance, Aziz Mdimi

Tanzania Journal of Engineering and Technology (TJET)

Traffic mobility is significantly influenced by road conditions and the internal factors governing vehicular performance. Internal factors play a crucial role in vehicular mobility, influencing vehicles operate and performance. While existing vehicular mobility models primarily address external factors, external factors such as governor, engine, gear train and differential unit remain underexplored. This study formulates a comprehensive model to address this gap, focusing on the internal components that affect vehicular mobility. The proposed model employs both analytical and numerical methods to derive transfer functions for these subsystems using Matrix Laboratory (MATLAB), aiming to capture the dynamic behavior of vehicles under various …

Ai-Driven Innovation And Development In Manufacturing: An Overview Of Trends, Issues, And Suggestions, Rongping Mu, Jingjing Guo, Yuchen Li, Qiang Li, Chun Jiang, Ze Feng, Guowei Dong

Bulletin of Chinese Academy of Sciences (Chinese Version)

Artificial intelligence technology has become a key force in driving innovation and development in global manufacturing industries, and its application in production automation, intelligent management, and other areas has become an important trend for innovation and development of manufacturing in all countries. This study comprehensively analyzes the innovation and development trend driven by artificial intelligence in global manufacturing, outlines the policies and measures of major countries in promoting the innovation and development of the manufacturing industries driven by artificial intelligence. It also points out the current situation and problems of the manufacturing’s innovation and development driven by artificial intelligence in …

Data Communication Over Power-Lines: A Review On Technical, And Applications Challenges, Abdi Abdalla

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a review study on the data communication over power-lines, commonly referred to as power-line carrier, power-line communication (PLC), mains communications, or power-line digital subscriber line (PDSL). This study examines the technical and application advantages and challenges associated with adopting PLC as a preferred alternative technology for wideband or broadband data communication. The broader coverage area of the PLC network gives it a distinct advantage over other communication network technologies. Additionally, implementing a communication system using the existing power-line network is more cost-effective and less time-consuming compared to constructing a new network from scratch. However, the primary challenge …

Assessment Of Web Security Vulnerabilities For Common Open Source Virtualization Software, Said Ally

Tanzania Journal of Engineering and Technology (TJET)

Open-source hypervisors have emerged as an integral technology for virtualizing server resources in cloud and data center computing. Hypervisor security efficiency is determined by virtual machine isolation, which is a de facto adoption factor in the selection process, as well as its ability to respond to web attacks. This paper assesses the security performance of Proxmox VE and XenServer for type 1 hypervisors, and Kernel Virtual Machine and Oracle Virtual Box for type 2 hypervisors. Security analysis was conducted using common exposures extracted from vulnerability databases and mapped against the OWASP 2013 and 2017 projects. For clarity, experiments were carried …

Investigations Of Cell Tower Antennas Parameters On Reduction Of Radio Frequency Radiation Levels From Radio Base Stations, Florence U. Rashidi

Tanzania Journal of Engineering and Technology (TJET)

The widespread deployment of mobile cellular base stations in populated areas has raised public health concerns due to increased exposure to radio frequency (RF) radiation emissions. Exposure to high levels of RF radiation can have potential thermal and non-thermal biological effects. Optimizing the configuration of cell tower antenna parameters is crucial for mitigating these radiation levels. This study therefore aims at systematically investigating the influence of different cell tower antenna parameters on reducing the RF radiation levels from mobile base stations. Field measurements were conducted at two cell sites shared by multiple mobile operators. Electric field strengths were measured at …