Mechanical Engineering Commons^™

Optimization Of Bearing Design In Centrifugal Pumps Using Finite Element And Experimental Methods: Application At South Refineries Company, Basra, Mohammed Hasab Naser Al-Mtasher

Al-Esraa University College Journal for Engineering Sciences

In the study, nonlinear vibration and thermo-mechanical characteristics of centrifugal pump bearings utilized in the cooling tower system of South Refineries Company (Basra) were properly examined using a combined experimental and numerical method. The intent of the study was to learn the impact of misalignment, the nature of the lubrication film, and thermal gradients on the stability of the operation of these bearings and their service life under realistic industry environment conditions. Finite element model (FEM) was constructed and tested on the basis of real field data obtained at the working pumps that allowed realistic distribution of stress and temperature. …

The Impact Of Gender Sensitization On Requirements Elicitation: A Controlled Experiment, Ruthbertha Kateule, Salome Maro, Leonard Peter Binamungu

Tanzania Journal of Engineering and Technology (TJET)

Previous studies in software engineering have reported the importance of considering gender aspects in various software engineering activities, including requirements engineering, however, to the best of our knowledge, no work has investigated the impact of gender sensitisation on eliciting gender inclusive software requirements. The objective of this study was to understand the impact of gender sensitisation on software requirements elicitation. We conducted a controlled experiment using 40 undergraduate students from three different computing programs at the University of Dar es Salaam. The 40 participants were divided into 9 groups with both males and females. The participants were asked to elicit …

Load Flow And Fault Performance Evaluation Of Interconnected Minigrids In Uganda Using Digsilent Powerfactory, Prossy Mutesi, Santos Kihwele, Emmanuel Matee

Tanzania Journal of Engineering and Technology (TJET)

The increasing demand for decentralized, reliable electricity in rural Sub-Saharan Africa has catalyzed the deployment of minigrids as an intermediate electrification strategy. This study investigates two solar photovoltaic (PV) mini-grids: Kyamugarura and Kanyegaramire, located in western Uganda, approximately 3km apart. Each mini grid initially consisted of 13 kW installed photovoltaic (PV) capacity, supplying power to households and small businesses. Due to rising demand and regular evening blackouts, both mini-grids are being upgraded to 57 kWp each. The integration of these upgraded systems into the national utility grid is proposed and simulated to evaluate performance improvements under two medium-voltage interconnection options: …

Trajectory-Based Model Predictive Control For Rotary Crane Sway Suppression With Only Horizontal Boom Actuation, Haryson J. Nyobuya

Tanzania Journal of Engineering and Technology (TJET)

Safety is of biggest importance in construction and industrial activities involving rotary cranes. These cranes are huge and responsible of moving large parts or/and materials from different positions. Now operating these cranes tend to be subdue to pay load oscillations when moving the load for which is extremely dangerous when not suppressed. This study proposes the generation of trajectory using Model predictive control approach with reduced control horizon compared to state horizon. Reduced control horizon design reduces computational time for trajectory generation while maintaining the pay-load sways to a minimum. In this approach the complex dynamic model is reduced to …

Hybrid Solar - Coal Thermal Energy System For Industrial Process Heat At Sayona Drinks Limited In Tanzania, Santos Kihwele, Elisha D. Bitesigirwe

Tanzania Journal of Engineering and Technology (TJET)

Over the past two decades, global efforts to mitigate pollution from conventional energy sources have intensified, with coal remaining a major contributor to carbon emissions. While fossil fuels cannot be eliminated from thermal generation in manufacturing industries, particularly in middle‑income countries such as Tanzania, they continue to dominate as the primary energy source. Industries including food and beverage, paper, textile, paints, chemicals, and pharmaceuticals require substantial thermal energy for heating and drying, and typically rely on coal and natural gas.This study introduces a unique application of a parabolic trough solar thermal system with integrated thermal energy storage, specifically tailored to …

Agentic Ai-Enabled Physics-Informed Machine Learning Framework For Intelligent Building Modeling, Control, And Automation, Zixin Jiang

Dissertations - ALL

Buildings account for a significant share of global energy consumption, and meeting the 2050 net-zero decarbonization targets requires retrofitting approximately 10,000 buildings per day in the United States alone. However, current human-centered workflows for building modeling, simulation, control, and operation remain too slow and labor-intensive to support deployment at this scale. This dissertation proposes an integrated two-pillar framework consisting of a physics-informed machine learning framework for integrated building modeling, control, and simulation, and a multi-agent agentic AI framework for automating building energy engineering workflows built on top of that foundation. The first pillar introduces a Physics-Informed Modularized Neural Network (PI-ModNN) …

Rapid Synthesis And Processing Of High-Capacity Layered Oxide Cathode Materials For Lithium And Sodium Batteries, Hansheng Li

Dissertations - ALL

Lithium-Manganese-Rich-Oxide (LMRO) is a type of layered oxide cathode active material with high energy densities of up to 900 - 1,000 Wh kg-1, competitive in capacity-demanding rechargeable lithium batteries. The increased energy density is beneficial for the range and recharging interval of electric vehicles. Based on layered Ni/Mn/Co oxide cathode materials, a high Mn content is chosen for this project as being abundant, while increased Ni concentration trades off thermal stability with specific capacity, while Co is carcinogenic and sourced less sustainably. Lithium content is increased along with Manganese content stoichiometrically as a second phase is introduced. Traditional synthesis routes …

Investigation Of Inlet Turbulence Effects On Mixing Characteristics Of A Jet In Crossflow, Erin Jagger

Masters Theses

Gas flaring is widely used in the oil and gas industry to dispose of excess waste gas, and improving flare efficiency is critical for reducing emissions. Flare performance depends strongly on turbulent mixing between the flare gas and surrounding crossflow. While previous studies have examined the effects of crossflow velocity and low turbulence levels, the combined effects of crossflow turbulence intensity and integral length scale on mixing remains insufficiently understood.

This study uses a non-reacting jet in crossflow (JICF) configuration to represent the mixing process between the flare and crossflow interaction. Using computational fluid dynamics (CFD), Reynolds-Averaged Navier-Stokes (RANS) simulations …

Enhancing The Barrier And Mechanical Properties Of Kraft Paper For Food Packaging Using Poly (Lactic Acid) Coatings Via Dip-Coating Technique, Putu Hadi Setyarini

Makara Journal of Science

Moisture-resistant kraft paper is important for food packaging because it helps preserve product quality and extend shelf life. However, untreated kraft paper exhibits limited barrier performance owing to the porous and hydrophilic nature of its cellulose structure. Herein, the mechanical and barrier properties of kraft paper were enhanced by applying poly (lactic acid) (PLA) coatings using a dip-coating technique with PLA concentrations ranging from 1 to 5 g/100 mL and either single- or double-dip-coating cycles. The results showed that increasing the PLA concentration and applying a double dip-coating treatment consistently improved coating thickness, tensile strength, elongation at break, water resistance, …

Nozzle Erosion Reconstruction Model For Data Analysis In Rocket Engines And Correlation With Chamber Pressure, Ryan J. Thibaudeau, Stephen A. Whitmore

Mechanical and Aerospace Engineering Student Publications and Presentations

Graphite nozzles remain the dominant choice for small hybrid and solid rocket motors operating on laboratory and university budgets, owing to their low cost, ease of machining, and rapid turnaround during iterative design campaigns. These same programs, however, must contend with the fact that graphite erodes through coupled thermochemical and mechanical mechanisms when exposed to the oxidizing species generated by high-energy propellant combustion, and the resulting throat-area growth fundamentally alters the time histories of chamber pressure, thrust, and delivered specific impulse. This paper presents a nozzle-erosion reconstruction model that extracts the time-resolved throat area from coupled thrust and chamber-pressure measurements …

Effect Of Heat Treatments On The Corrosion Resistance Of A Trip Steel And Its Evaluation By Non-Destructive Testing, Karla Ivette Vega-Nava, Ariosto Medina-Flores, Marco Antonio Espinosa-Medina, José Sergio Pacheco-Cedeño, Héctor Guillermo Carreón-Garcidueñas, Francisco Fernando Curiel-López, Jose Jaime Taha-Tijerina

Mechanical Engineering Faculty Publications

The development of advanced high-strength steels (AHSS) for the automotive industry requires optimizing the balance between mechanical properties and durability in aggressive environments. This study investigates the effects of two heat treatment routes on the microstructure and corrosion resistance of a transformation-induced plasticity (TRIP) steel (Fe-0.2C-1.75Mn-0.5Si-1Al). Route A includes a full austenitizing step at 1000 °C prior to intercritical annealing, whereas Route B omits this step and begins directly with intercritical annealing at 800 °C. Microstructural characterization (SEM/XRD), electrochemical assays, and eddy current tests were employed. The results revealed that Route A yields a homogeneous microstructure with 12.7% retained austenite, …

Vibration Diagnostics For Industrial Machinery: From Signal Processing To Deep Learning, Walid M. Shewakh

Emirates Journal for Engineering Research

When machines break down unexpectedly, it costs factories a lot of money and can even put workers at risk. That is why vibration analysis has become such a big deal in predictive maintenance. By listening to how a machine vibrates, engineers can often tell something is wrong before the whole thing falls apart. This paper looks at how we have gotten better at this over the years. We started with fairly basic signal processing, things like Fourier transforms that have been around for ages, and now we are seeing some really interesting work with neural networks and deep learning. I …

Mae Enewsbrief January-March 2026, Department Of Mechanical And Aerospace Engineering, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

Ion Irradiation Of Microelectromechanical Resonators, Hengky Chandrahalim, David D. Lynes

AFIT Patents

A method of enhancing an electromechanical coupling coefficient of a microelectromechanical (“MEMS”) device. The method includes applying, to a fully fabricated MEMS device, heavy particle ion radiation to the MEMS device at a fluence of at least 1×10¹⁴ cm.⁻². According to other embodiments of the present invention are directed to a bandpass filter comprising a plurality of MEMS devices fabricated in accordance with the methods provided. The MEMS of the plurality are electronically or mechanically coupled.

Improved Method Of Evaluating Gas-Phase Air Cleaners Considering Adsorption And Desorption Mechanisms To And From Internal Test Chamber Surfaces, Casey Douglas Coffland

Dissertations and Theses

Portable air cleaners are playing an increasingly important role in managing indoor air quality in response to pressing issues like wildfire smoke events. Smoke is a complex mixture of gases and particulate matter; while established test methods exist for particulate matter, the dynamic behavior of gaseous pollutants is not well accounted for in current test methods. This is because prevailing air cleaner testing methods typically treat background losses as irreversible, whereas gases can engage in partitioning to and from test chamber surfaces. Ignoring these sorption interactions causes inaccurate estimation of an air cleaner's impact.

A new approach has been developed …

Topographical Mobility Envelope Modeling And Geometric Analysis For Off-Road Unmanned Ground Vehicles, Huashuai Fan

ETDs from 2020-2029

This dissertation introduces topographical mobility as a quantitative framework for assessing off-road unmanned ground vehicle performance based on geometric interaction between the vehicle and terrain. Rather than relying on conventional discrete indices, the proposed formulation evaluates mobility directly from vehicle and terrain geometry, expressing vehicle capability in terms of radius constraints implied by its dimensions and suspension state. On the vehicle side, longitudinal and lateral mobility radii are derived analytically from vehicle geometry—wheelbase, track width, ground clearance, and lowest underbody point location—quantifying the minimum terrain radius negotiable without underbody interference. Suspension state is shown to alter longitudinal mobility radius by …

Centrifugally Spun Silica Fibers For Lithium-Ion Battery Anodes: Structure And Cycling Stability, Alejandra Guerrero, Valeria Tirado, Jason Parsons, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications

Introduction: Silicon dioxide (SiO2) fiber structures have attracted attention as alternative anode materials for lithium-ion batteries because of their ability to improve cycling stability compared to commercial silicon particles.

Materials and methods: SiO2 composite fibers were prepared by centrifugal spinning of polyvinylpyrrolidone (PVP)/SiO2 precursor solutions followed by calcination at 500–700 ◦C for different holding times to produce short-fiber composites and micro-belt SiO2 fiber structures. The morphology and crystal structure of the SiO2 short fibers and micro-belts were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS). Electrochemical performance was evaluated using CR2032 half-cells.

Results: The …

Optimizing Graphene Oxide In Self-Compacting Concrete: A Sustainable Nano-Material Strategy For Enhanced Durability And Structural Performance, Mohammed Shakeebulla Khan, Vijaya G. S

Journal of Sustainable Construction Materials and Technologies

In order to reduce the environmental impact of the constructed world, advanced and sustainable construction materials are needed. This work is a summary of the comprehensive study on a novel self-compacting concrete with nano-engineered material (graphene oxide) modified self-compacting concrete (GO-SCC). The optimum dosage of GO was determined using Taguchi method, Analysis of Variance (ANOVA) and Response Surface Methodology (RSM) multi-objective statistical optimization method, and was found to be 0.10% by weight of cement (bwoc). This dosage of 0.10% GO led to the overall desirability score of 0.87, which confirmed that this was the optimum dosage for six response variables …

Processing Mechanism And Efficacy Maintenance Strategy Of Ginseng Active Ingredients Based On Spectroscopy Technology, Yang Hantong, Kong Linghui, Jiang Mengmeng, Wang Yingxiu, Li Xiangguo

Food and Machinery

Ginseng, as a medicinal and edible plant, has ginsenosides as its core active components, which are widely applied due to their physiological functions such as antioxidant and anti-inflammatory activities; however, their structures and activities are easily affected by food processing. During processing steps such as cleaning, steaming/boiling, and fermentation, temperature, pH, and microbial enzyme systems alter the types, contents, and stability of active components through reactions such as hydrolysis and oxidation. The intrinsic linkage mechanism of "component transformation-activity-bioavailability" constitutes a core focus and challenge in current research. This study, based on spectroscopic techniques including high-performance liquid chromatography (HPLC), nuclear magnetic …

Beneficial Investigation Of Sustainable Recycled Waste Plastic In Treating The Consolidation Behavior Of Fine Soil, Aram Mohammed Raheem, Cumaraswamy Vipulanandan, Mohammed Hiwa Abdullrahman, Ali Tariq Omer

Journal of Sustainable Construction Materials and Technologies

Recycled waste plastic is one of the regular garbage utilized as a sustainable material in soil remediation. This study examines the efficacy of utilizing local recycled waste plastic as an ecological quantifiable along with soil containing fine particles to analyze the consolidation behavior. Various recycled waste plastic contents ranging from 2% to 10% were employed experimentally in two patterns where in the first pattern the recycled waste plastic were mixed as dry material with the fine soil particles while in the second pattern a sandwich layer of 10% of the recycled waste plastic was placed in the middle of the …

Enhanced Thermal Energy Storage In Buildings: Impregnation, Leakage, And Environmental Performance Of Organic And Inorganic Pcm Composites, Gökhan Genç, Esra Yılmaz, M. Yusuf Yazıcı

Journal of Sustainable Construction Materials and Technologies

This study experimentally investigates the impregnation and leakage performance of various organic (tobacco, sawdust, bay leaf, black cumin) and inorganic (vermiculite, perlite, bentonite, sepiolite) carrier materials used for phase change material (PCM) integration in building applications. The commercial paraffin-based PCM RT-31 was used as the thermal storage medium. Impregnation and leakage tests were conducted to evaluate the PCM absorption capacity, form stability, and energy storage potential of each carrier. The results revealed that perlite (C = 80%) and bay leaf (C = 78%) exhibited the highest impregnation capacities due to their porous and fibrous structures; however, they also demonstrated significant …

Modeling Of Tensile Stress-Strain Response For Steel Fiber Reinforced Self-Compacting Concretes, Anıl Niş, Nilufer Özyurt, Turan Özturan

Journal of Sustainable Construction Materials and Technologies

Main aim of the research was to further understand self-compacting concrete reinforced with steel fibers (SFR-SCC) behavior and to contribute modeling of the tensile stress-strain diagrams for the standardization of the fiber reinforced materials for structural utilization. Fiber reinforced materials has not been used without structural rebar because of the absence of stress-strain curve in tension required for the structural design codes. Hence, an inverse analysis (multi-layer model) was further modified for various steel fibers to predict tensile stress-strain behaviour. For this purpose, 5 different mixes; control, reinforced with long fibers with 0.5% and 1%, short fiber with 0.5% and …

Optimization Of Bio-Briquettes Production From Cassava Stems Co-Blended With Sisal Bole Bagasse Using Response Surface Methodology, Agnes Nshoma Msobi, Neema O. Msuya, Kando Khalifa Janga

Tanzania Journal of Science

This research aimed at producing bio-briquettes from cassava stems and sisal bole bagasse as an alternative source of cooking energy. A Response Surface Methodology (RSM) with Face - Centered Central Composite Design (FCCCD) featured a multi-objective optimization of the effect of the production parameters, focusing on maximizing char yield and Higher Heating Value (HHV) of the produced briquette while minimizing carbonization temperature and residence time. The findings showed that bio-briquettes produced at the lowest temperature (250 ℃) and residence time (30 min) and the blending ratio of 75% by 25% had the highest char yield of 76.92% and HHV of …

Load Profile Analysis And Forecasting For Rural Mini Grids In Uganda, Prossy Mutesi, Santos L. Kihwele, Emmanuel S. Matee

Tanzania Journal of Science

Accurate load forecasting is essential for the reliable and cost-effective operation of rural mini grids, where constrained generation capacity and high penetration of renewable energy resources require well-informed operational decisions. This study examines electricity demand characteristics and forecasting performance for the Buzaami and Ssenyondo mini grids in Uganda, with particular focus on diurnal load profiles, peak demand behavior, and seasonal variability. 2022 operational data show extended peak demand from early morning to late evening, driven by socio-economic activities that strain resource scheduling and reliability management. To address these challenges, the study evaluates and compares Long Short-Term Memory (LSTM) networks, fuzzy …

Ontology-Based Decision Support System For Improving Aquaculture Management, Thuy Thi Thu Pham, Phuong Thi Can, Nga Thi Thanh Ha

Journal of Marine Science and Technology–Taiwan

Early detection of shrimp diseases is vital for reducing losses and ensuring sustainable aquaculture. In this study, a novel ontology-driven framework for shrimp disease diagnosis that integrates environmental knowledge with machine learning-based image analysis is proposed. An ontology was constructed from a structured dataset of environmental parameters and farm conditions related to shrimp diseases, which formally represents concepts such as farm characteristics, environmental factors, symptoms, and disease types. Two public shrimp image datasets were subsequently used to train convolutional neural networks (ResNet50 and MobileNetV2) for automated disease classification. The predicted disease labels and confidence scores were mapped onto the ontology. …

Case Study On Operational Performance Improvement By Turbocharger Nozzle-Ring Modification In Shipboard Generators, Jong-Hun Im, Mukyeong Kang, Sang-Deuk Lee

Journal of Marine Science and Technology–Taiwan

Owing to increasingly stringent emission regulations imposed by the International Maritime Organization and rising fuel prices, the demand for enhanced energy efficiency and emission control in marine power systems is increasing. This study presents a case study in which the performance of an aging auxiliary generator is restored by modifying the turbocharger nozzle ring. The vessel, a 12-year-old crude-oil tanker, experienced repeated operational issues with its No. 3 generator. This included elevated exhaust gas temperatures, reduced intake air pressure, and frequent turbocharger surges. To address these challenges, the nozzle-ring blade angle was reduced by approximately 2° using spare components, while …

Towards Sustainable Marine Education: Assessing High School Students’ Understanding Of Conservation Concepts, Cheng-Chieh Chang, Tsuyoshi Sasaki, Ya-Yin Liao, Ling-Ya Hung, Liang-Ting Tsai

Journal of Marine Science and Technology–Taiwan

This study assesses the concepts of marine resource conservation and sustainability among Taiwanese high school students by developing a Chinese version of the Marine Resources Conservation and Sustainability Scale. Grounded in the cognitive, socio-emotional, and behavioral learning objectives outlined in UNESCO’s Education for Sustainable Development Goals (ESDGs), the scale targets students aged 16 to 18 to examine gender differences in marine knowledge and conservation concepts. The scale comprises 31 items across four dimensions: the first section evaluates marine knowledge, while the remaining dimensions utilize a four-point Likert scale to assess cognitive, socio-emotional, and behavioral learning objectives, respectively. The results indicate …

Dynamic Governance Of Transboundary Fisheries Through Deep Learning And High-Frequency Vessel Tracking Data For Climate-Resilient Management: An Application To The East China Sea, Qin Lin, Yaqing Shu, Manel Grifoll, Hongxiang Feng

Journal of Marine Science and Technology–Taiwan

Transboundary fisheries governance is increasingly challenged by jurisdictional conflicts, regulatory asymmetries, and climate-induced stock shifts in fish stocks, especially in contested regions like the East China Sea (ECS). This study capitalizes on China’s high-frequency BeiDou Navigation Satellite System (BDS) data (June 2021–May 2022) to pioneer a CNN-BiLSTM deep learning model to dynamically identify fishing hotspots and evaluate policy effectiveness. By integrating vessel trajectories, environmental variables, and regulatory events, we examine spatiotemporal patterns of fishing effort relative to seasonal bans, extreme weather, and quota systems. Key findings reveal: (1) post-moratorium (September–December) concentration of fishing intensity, peaking in November; (2) significant weather-driven …

Lock Scheduling Decisions And Strategy Optimization Under Operation Interruption Scenarios, Junhe Li, Qiang Zhang, Junpeng Jiang, Jiangchao Bao

Journal of Marine Science and Technology–Taiwan

Locks are critical nodes in inland waterway transportation systems that concentrate vessel traffic between upstream and downstream reaches, making their operations highly sensitive to hydrological conditions. Therefore, disruptions caused by droughts, floods, or routine maintenance can easily trigger congestion. To address this issue, this study systematically examines the interrelationships among the number of ships awaiting passage, scheduling strategies, the trade-off between lock chamber utilization and ship waiting time, the influence of ship entry sequences on user satisfaction, and the combined effects of these factors on overall lock scheduling performance. Based on these analyses, an integrated decision-making model for two-stage ship …

Corrosion Protection Assessment Of Offshore Wind Turbine Substructures Using Beasy Cp Simulation Analysis, Chuan-Yang Wan, Hung-Hua Sheu, Sheng-Yu Wang, Yao-Ming Wang, Wei-De Chen, Ming-Yuan Lin, Hung-Bin Lee

Journal of Marine Science and Technology–Taiwan

This study investigates the corrosion protection assessment of offshore wind turbine substructures established in the waters off Keelung, Taiwan. First, a cathodic protection system for the monopile foundation is designed and established. The Boundary Element Method (BEM) is applied using the BEASY simulation software to develop a 3D geometric model for cathodic protection. In the steel monopile simulation analysis, the exposed marine environment is set based on the sea conditions of the Keelung small boat marina, including parameters such as salinity, resistance, and polarization curves, to establish an effective cathodic protection system for underwater structures. By simulating these parameters, a …