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2026 (Spring) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department Apr 2026

2026 (Spring) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department

ENSI Informer Magazine Archive

The ENSI Informer Magazine published in the spring of 2026.


Engineering Cryogenic Thermal Links And Transport Systems For Conduction-Cooled Superconducting Cavities, Jacob B. Lewis Apr 2026

Engineering Cryogenic Thermal Links And Transport Systems For Conduction-Cooled Superconducting Cavities, Jacob B. Lewis

Mechanical & Aerospace Engineering Theses & Dissertations

The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is currently developing a prototype conduction-cooled 915 MHz SRF cryomodule proposed for industrial use, capable of increasing the energy of an electron beam with 5 mA current by ~ 4 MeV. Two Nb3Sn resonant cavities are under development for this project, in which cryogenic cooling is provided by closed cycle refrigerators (cryocoolers). One cavity utilizes high-purity electroformed copper on the outer surface to provide heat extraction from the cavity, the other relies on high-purity aluminum thermal links. This thesis investigated the thermal conduction pathways between the cavities and cryocooler cold heads, with …


Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans Apr 2026

Observations Of An Oscillatory Mechanochemical Reaction Between Tetrathiafulvalene And Chloranilic Acid, Alastair Deans

Physics Theses & Dissertations

Mechanochemistry is the study of chemical reactions driven by the input of mechanical en ergy in addition to thermal activation. Mechanochemical reactions from powders are carried out by manual grinding or milling using various types of ball mills, or in twin extruders. While mechanochemistry has great potential affording economically and environmentally advantageous “green” synthetic methods, a drawback is that its chemical mechanisms are not well understood. One example of such a reaction currently under study involves tetrathiafulvalene, an organic elec tron donor with two polymorphs (orange and brown), and chloranilic acid, an electron acceptor. Previous results show that neat grinding …


Enhancing Nasa Sounding Rocket Capabilities Through Composite Material Adoption, Robert Burth Apr 2026

Enhancing Nasa Sounding Rocket Capabilities Through Composite Material Adoption, Robert Burth

Mechanical & Aerospace Engineering Theses & Dissertations

Sounding rockets are a suborbital research platform employed by NASA for heliophysics, astrophysics, geospace science investigations, and for technology development. They follow semi-parabolic trajectories and are launched using surplus military, and commercial, solid-propellant rocket motors. NASA sounding rocket payloads are comprised of standard, modular subassemblies, designed to perform specific functions critical to achieving specific mission success criteria.

Since the program’s inception, payload length and mass have trended upwards, limiting the capability of the platform to reach exospheric apogees and decreasing the time above critical altitudes to observe solar and celestial targets. To offset this trend, composite materials may be of …


Natural Convection Of Cuo-Water Nanofluid Flow Along A Vertical Plate With Variable Thermophysical Properties And Discrete Heat Sources, Nepal Roy, Ioan Pop, Rama Subba Reddy Gorla Apr 2026

Natural Convection Of Cuo-Water Nanofluid Flow Along A Vertical Plate With Variable Thermophysical Properties And Discrete Heat Sources, Nepal Roy, Ioan Pop, Rama Subba Reddy Gorla

Faculty Publications

Effects of discrete heat sources along a vertical plate are of practical importance due their occurrence in electronic devices. For growing demand of electronic appliances and their advancement, cooling processes of them must be improved. As usual fluids have limited heat transfer, nanofluids made by dispersing nanoparticles into them are utilized to enhance thermal performance. However, flow characteristics and heat transfer of a nanofluid for discrete heat sources along a vertical plate need to be explored. For this reason, this study analyzes the natural convective heat transfer and flow behaviors of CuO-water nanofluid induced by discrete heat sources along a …


Quantum Spin-Like Behavior Of Elastic Guided Waves: Quantized Geometric Phase For Nde And Shm, Md Ebrahim Khalil Bhuiyan Apr 2026

Quantum Spin-Like Behavior Of Elastic Guided Waves: Quantized Geometric Phase For Nde And Shm, Md Ebrahim Khalil Bhuiyan

Theses and Dissertations

Ultrasonic guided waves are widely used in nondestructive evaluation (NDE) and structural health monitoring (SHM) for detecting defects and damage in engineering materials and structures. Conventional diagnostic features, such as attenuation of wave amplitude, shifts in time-of-flight, and frequency variations are widely used for damage identification. However, these metrics are inherently sensitive to environmental and operational variations, including temperature, pressure, humidity, sensor coupling conditions, boundary constraints, and external loading. Such sensitivities introduce significant uncertainty in signal interpretation, often obscuring damage-related signatures. Recent advances in wave physics have revealed that elastic guided waves exhibit intrinsic spin angular momentum (SAM), arising from …


Development And Optimization Of Aluminum-Water Reactors For Efficient And Sustainable Hydrogen Production, Guru Prasad Dhungel Apr 2026

Development And Optimization Of Aluminum-Water Reactors For Efficient And Sustainable Hydrogen Production, Guru Prasad Dhungel

Theses and Dissertations

Hydrogen is a promising clean energy carrier; however, safe, controllable, and on- demand hydrogen generation remains a significant engineering challenge. Aluminum– water reactions offer high theoretical hydrogen yield, but practical implementation is limited by oxide passivation and difficulty in maintaining stable thermal and pressure conditions.

This study investigates hydrogen generation from aluminum foam–steam reactions under controlled temperature and pressure using engineered reactor configurations. Three reactor designs, horizontal, vertical, and cylindrical—were experimentally optimized, developed and evaluated to enhance hydrogen production rate and pressure stability without chemical additives. The experiments focused on heat transfer behavior, steam management, pressure buildup, and reaction stability. …


Strain-Induced Oxygen Vacancy Effect On Thermoelectric Properties In Oxide Thin Films, Ebenezer Seesi Apr 2026

Strain-Induced Oxygen Vacancy Effect On Thermoelectric Properties In Oxide Thin Films, Ebenezer Seesi

Theses and Dissertations

The development of highly efficient and cost-effective thermoelectric (TE) materials is critical for converting waste heat into electricity in advanced power generators. For high-temperature TE applications, transition metal oxides (TMOs) have attracted significant interest because they are comparatively safe, earth-abundant, and stable under oxidizing conditions where many conventional heavy-metal and chalcogenide TE materials degrade. However, the TE performance of TMOs is limited by the intrinsic trade-off between the Seebeck coefficient (S) and electrical conductivity (σ), both of which depend inversely on charge carrier concentration. This constraint limits the achievable power factor (PF = S²∙σ) and remains a central obstacle for …


Plasma Dynamics And Chemistry In Atmospheric Pressure, Ayoub Al Wahaibi Apr 2026

Plasma Dynamics And Chemistry In Atmospheric Pressure, Ayoub Al Wahaibi

Theses and Dissertations

Atmospheric-pressure plasmas are attractive for practical chemical and energy applications because they can be generated without vacuum systems and can produce reactive environments under relatively mild bulk conditions. However, these discharges are often non-uniform and highly sensitive to operating conditions, especially when water or multiphase flows are introduced. This dissertation investigates how atmospheric- pressure plasma behavior and plasma-driven chemistry change in three challenging but application-relevant regimes: water-mist dielectric barrier discharges (DBDs), multiphase plasma-assisted fuel reforming, and striated AC glow discharges. The work combines optical and electrical diagnostics, imaging, chemical analysis, and time-dependent analysis to connect discharge characteristics with measurable chemical …


Deep Learning Models For Anomaly Detection In Industrial Inspection, Jiawei Guo Apr 2026

Deep Learning Models For Anomaly Detection In Industrial Inspection, Jiawei Guo

Theses and Dissertations

Anomaly detection plays a pivotal role in ensuring the longevity and safety of engineered systems, particularly in domains where defects can have significant operational or economic consequences. From internal damage in structural parts to subtle visual defects in manufactured components, identifying abnormal patterns requires models that are both computationally efficient and suitable for real-world deployment. This dissertation explores deep learning-based solutions designed to address these challenges, with a focus on Structural Health Monitoring (SHM) and industrial defect inspection under real-world scenarios.

This dissertation first addresses the problem of efficient and reliable component- level perception with limited supervision and strict hardware …


Laser-Based Wideband Guided Ultrasonic Wave Inspection Of Isotropic And Anisotropic Materials, Andrew Philip Campbell Apr 2026

Laser-Based Wideband Guided Ultrasonic Wave Inspection Of Isotropic And Anisotropic Materials, Andrew Philip Campbell

Theses and Dissertations

Non-destructive evaluation (NDE) and structural health monitoring (SHM) have experienced significant growth in both capability and utility as material evaluation and damage detection methods for structural components throughout various industries over the past two decades. Evaluating a structure throughout its life cycle or on demand as needed can identify critical weaknesses that impact safe operation and may prevent failures. Various NDE/SHM methods have been shown to be effective; among them, guided ultrasonic waves (GUW), particularly Lamb wave-based methods, have been intensively studied due to their capability to interrogate internal defects and their relatively larger coverage. With the advancements in new …


Optimizing Auv Perception For Competitive Underwater Robotics: Analyzing Performance And Simplicity Of Machine Vision Hardware, Joseph King Apr 2026

Optimizing Auv Perception For Competitive Underwater Robotics: Analyzing Performance And Simplicity Of Machine Vision Hardware, Joseph King

Honors Theses

Underwater robotics is a growing field with many practical applications, such as pipeline and offshore structure monitoring, deep sea mining, mine reconnaissance/removal, and marine environmental monitoring. USM’s Robotics Club will participate in the international RoboSub competition, where student-led teams build autonomous underwater vehicles (AUVs) that perform a variety of tasks within a pool requiring camera-based object detection. This project analyzes affordable hardware and software options for providing machine vision to USM’s future RoboSub AUV. The performance of an ESP32-CAM microcontroller, Raspberry Pi 5, and Jetson Orin Nano single-board computers running FOMO and YOLO object detection models was compared. These models …


Modeling And Autonomous Control Systems For A Delivery Drone Application, Dana Helal Alnuaimi Apr 2026

Modeling And Autonomous Control Systems For A Delivery Drone Application, Dana Helal Alnuaimi

Theses

This thesis focuses on the development of a multi-drone navigation and control system, aiming to enhance payload capacities beyond the limits of single-drone systems. By integrating multiple drones to work collaboratively as a unit, this study addresses the challenges associated with lifting and transporting heavier payloads.

The primary objective is to design and evaluate a multi-drone system capable of working in tandem to transport larger payloads efficiently. The research aims to develop robust control algorithms, supported by system identification for dynamic modeling, and navigation strategies to enable effective coordination between drones.

The study employs a combination of simulation and real-world …


Development Of A Novel Cfd Approach For Predicting Multiphase Flow Enhanced By Machine Learning, Abdulrahman Elazazi Salem Apr 2026

Development Of A Novel Cfd Approach For Predicting Multiphase Flow Enhanced By Machine Learning, Abdulrahman Elazazi Salem

Theses

Accurate estimation of interface orientation is crucial for ensuring both the accuracy and robustness of Volume of Fluid (VOF) schemes in multiphase flow simulations, especially when using non-uniform Cartesian meshes. Conventional gradient reconstruction approaches, such as least-squares (LSQ) methods, often suffer from significant errors and strong oscillations on highly stretched grids. This work proposes a grid-transferable, learning-based methodology that predicts interface unit normal vectors directly from the local volume-fraction field on nonuniform structured Cartesian grids using a feedforward neural network. The methodology extends earlier work originally developed for uniform grids, which is first reproduced to assess how performance deteriorates in …


Study Of The Effect Of Biodiesel Derived From Jojoba Oil With Alcohols Blends On Diesel Engine Performance, Exhaust Emissions, Vibration, And Noise, Yassir Abdelrahman Elbashier Apr 2026

Study Of The Effect Of Biodiesel Derived From Jojoba Oil With Alcohols Blends On Diesel Engine Performance, Exhaust Emissions, Vibration, And Noise, Yassir Abdelrahman Elbashier

Theses

This study presents a mutual investigation on the properties of the fuels and the performance of an engine using biofuels from mixtures of jojoba oil biodiesel with alcohols. The work consists of mainly two phases, examining the properties of the jojoba biodiesel-alcohols mixtures and the performance and emission behavior in a single piston diesel engine. A base mixture of 50% jojoba biodiesel and 50% diesel produced, and this was fractionally mixed with 5, 10, and 20% methanol and with 5, 10, and 20% diethyl ether (DEE). The rheological properties namely viscosity and shear stresses of all biodiesel blend mixtures were …


Ellie - Exteroceptive Light Locomotion In Eukaryote-Fungi, Brandon Etwarroo Apr 2026

Ellie - Exteroceptive Light Locomotion In Eukaryote-Fungi, Brandon Etwarroo

Doctoral Dissertations and Master's Theses

Over the past decade, fungal research and its technological applications have expanded across multiple disciplines, including the emerging field of biohybrid systems. This thesis develops and evaluates a wireless, untethered mobile robot controlled by the action potential-like activity generated by Pleurotus ostreatus sporocarps under red, green, and blue optical stimulation. Light is applied to the sporocarps, the resulting electrical responses are recorded, and these signals are transmitted wirelessly to actuate the mobile robot. Both the action potential-like activity patterns and the robot’s movement trajectories were analyzed. The results demonstrate that wireless robotic control mediated by fungal electrophysiology is feasible. Overall, …


Effect Of Nozzle Pressure Ratio On Thrust And Flow Behavior In A Supersonic De Laval Nozzle, Esha Jain Apr 2026

Effect Of Nozzle Pressure Ratio On Thrust And Flow Behavior In A Supersonic De Laval Nozzle, Esha Jain

Doctoral Dissertations and Master's Theses

Supersonic nozzles operate across a range of flow regimes. While an ideally expanded condition yields optimal thrust, practical propulsion systems rarely operate at this design point due to variations in altitude and engine operating conditions. As a result, nozzles frequently operate in off-design conditions. In overexpanded regime, where the exit pressure is lower than the ambient pressure, shock-induced separation may occur within the divergent section of the nozzle, potentially degrading nozzle performance. Understanding the aerodynamic behavior of nozzles operating under off-design conditions is therefore important for improving propulsion system performance and stability. In particular, direct thrust measurements provide a key …


Additive Manufacturing Of Ti-Ni Based Ternary Shape Memory Alloys, Yitao Chen, Frank Liou Apr 2026

Additive Manufacturing Of Ti-Ni Based Ternary Shape Memory Alloys, Yitao Chen, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metal additive manufacturing has become a powerful tool to develop customized metal alloys and to discover more advanced properties for novel extended applications. Ti-Ni based shape memory alloy is a group of intriguing smart functional materials, and adding a small amount of a third element can promote and induce more attractive functions. Due to the difficulty in traditional processing and the unique feature of material flexibility of in-situ alloying in additive manufacturing processes, not only Ti-Ni binary shape memory alloys but also Ti-Ni-X ternary shape memory alloys can be developed, manufactured, and investigated in-depth by additive manufacturing. This paper provides …


Cavitation-Aware Design Of Hydrofoil Sections For Marine Propeller Blade Development, Samuel G. Bacon Apr 2026

Cavitation-Aware Design Of Hydrofoil Sections For Marine Propeller Blade Development, Samuel G. Bacon

Mechanical & Aerospace Engineering Theses & Dissertations

Cavitation is a major design constraint for marine propeller blade sections because it can reduce hydrodynamic performance, increase vibration and noise, and contribute to surface damage. This thesis develops and applies an exploratory computational framework for cavitation-aware hydrofoil-section design relevant to marine propeller blade development. The framework combines section-level CFD validation, CST-based geometry parameterization, pressure-based pre-screening, matched-load comparison, and focused predicted inception envelope or cavitation-bucket analysis.

The CFD methodology was validated against published YS-920 hydrofoil water-tunnel data using selected fully wetted, near-inception, and cavitating reference cases. The validation results showed that the adopted framework reproduced the key experimental trends needed …


Ultra-High Vacuum Outgassing Characterization Of Thermally Processed Low-Carbon Steel For Advanced Particle Accelerator And Gravitational Wave Detector Applications, Aiman H. Al-Allaq Apr 2026

Ultra-High Vacuum Outgassing Characterization Of Thermally Processed Low-Carbon Steel For Advanced Particle Accelerator And Gravitational Wave Detector Applications, Aiman H. Al-Allaq

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation investigated AISI 1020 low-carbon steel as an alternative vacuum chamber material to conventional stainless steel for ultra-high vacuum (UHV) and extreme-high vacuum (XHV) applications. After a 400 °C/48 h bake, AISI 1020 tube chambers achieved a hydrogen outgassing rate of 2.4 × 10⁻¹⁶ Torr·L·s⁻¹·cm⁻², approximately 2,300 times lower than the prebaked 316L stainless-steel comparator, among the lowest hydrogen outgassing rates ever reported for an uncoated metallic vacuum chamber. Bare and magnetite-coated AISI 1020 chambers were then compared using throughput and rate-of-rise methods. The magnetite coating yielded 5× lower water outgassing at room temperature, but this advantage disappeared after …


Tuning And Performance Of Pid Controlled Low Complexity Systems, Timothy Evans Apr 2026

Tuning And Performance Of Pid Controlled Low Complexity Systems, Timothy Evans

Honors Theses

Proportional integral derivative (PID) controllers are used for precise position and orientation control in systems such as autonomous underwater vehicles (AUVs). This project supports the University of Southern Mississippi’s (USM) Robotics Club’s RoboSub AUV effort by developing, troubleshooting, and manually tuning PID controllers to characterize tracking performance and settling time across systems of increasing complexity. Initially, the project hypothesized that tracking performance would be reduced and settling times would increase as system complexity advanced from one degree-of-freedom (DOF) to two DOF. However, prior research was found that suggests that for small disturbances around an equilibrium state, separate PID-controlled DOFs can …


Community Engagement Through Robotics Mentoring – Unlv, First Nv, And High School Robotics Teams, Brendan O'Toole Mar 2026

Community Engagement Through Robotics Mentoring – Unlv, First Nv, And High School Robotics Teams, Brendan O'Toole

Community Engagement Expo Research Posters

The UNLV Robotics Mentorship program includes a two-semester course that trains students to support local high school FIRST Robotics Competition (FRC) teams. ‘ME 464 Robotics Mentoring I’ provides training in design, mentoring,  fabrication, and programming. ‘ME 465 Robotics Mentoring II’, pairs students with local high school teams to serve as technical mentors for the competition season.


Asymmetric Airfoil Selection For A Small-Scale Vertical Axis Wind Turbine: A Numerical Study, Babak Ranjbaran, Yonatan Afework Tesfahunegn, Raul Bayoan Cal, Ármann Gylfason Mar 2026

Asymmetric Airfoil Selection For A Small-Scale Vertical Axis Wind Turbine: A Numerical Study, Babak Ranjbaran, Yonatan Afework Tesfahunegn, Raul Bayoan Cal, Ármann Gylfason

Mechanical and Materials Engineering Faculty Publications and Presentations

Vertical-axis wind turbine (VAWT) efficiency depends mainly on the aerodynamic properties of the airfoils used in their blades. During each rotation of the turbine, the blade experiences a range of angles of attack (AOAs) with respect to the relative wind, resulting in a variation of its contribution to the overall performance of the turbine. This paper leverages the capabilities of XFoil for preliminary performance analysis and ANSYS Fluent for detailed Computational Fluid Dynamics (CFD) simulations. The initial selection of airfoils is based on geometric characteristics and their potential for high tangential force coefficients. The asymmetric airfoils were selected by maximizing …


Sweep Angle Effects Of Flow Over A Seal Whisker-Inspired Undulated Cylinder, Trevor Dunt, Christin T. Murphy, Ondrej Fercak, Raúl Bayoán Cal, Jennifer A. Franck Mar 2026

Sweep Angle Effects Of Flow Over A Seal Whisker-Inspired Undulated Cylinder, Trevor Dunt, Christin T. Murphy, Ondrej Fercak, Raúl Bayoán Cal, Jennifer A. Franck

Mechanical and Materials Engineering Faculty Publications and Presentations

Flow over a seal whisker-inspired undulated cylinder at swept back angles is computationally investigated, comparing the vortex shedding, forces, and wake characteristics to those of an equivalent smooth geometry. Numerous prior studies have demonstrated that undulated cylinders can reduce mean drag and unsteady lift oscillations; however, none have isolated the effects of the sweep angle resulting from whisker positioning in flow. Inspired by the active control seals exert over their whiskers while navigating and sensing in unsteady aquatic environments, this study investigates how such orientation influences the hydrodynamic performance of the geometry. Simulations are performed of flow across a rigid, …


Wearable Sensor System Used To Measure Linear And Angular Acceleration Of The Head Of American Football Players, David A. Emerson Mar 2026

Wearable Sensor System Used To Measure Linear And Angular Acceleration Of The Head Of American Football Players, David A. Emerson

LSU Master's Theses

American football players are repeatedly subject to high-velocity impacts; collisions can exceed 100 g in the NFL [1]. Rotational accelerations of the head caused by high-velocity collisions have been proven to be extremely damaging to the highly organized brain fibers at the brain-skull interface [2]. The sensor system (SS) measures the nonplanar acceleration at four locations on a chin strap using ADXL314 accelerometers and utilizes rigid-body kinematics to estimate the head rotational state from the measured acceleration of the SS [3]. The SS was validated through progressive testing, including steady-state, linear impact, and rotational impact testing. The ADLX314 sensor exhibited …


Deep Learning Based Control System For Multi-Zone Hvac Residential Buildings, Mohammad H. Z. Alghalayeeni Mar 2026

Deep Learning Based Control System For Multi-Zone Hvac Residential Buildings, Mohammad H. Z. Alghalayeeni

Mechanical Engineering Theses

Heating, ventilation, and air conditioning (HVAC) systems are major contributors to residential energy consumption. However, most homes continue to rely on single zone thermostat control, which regulates temperature based on a single sensor and cannot account for thermal variations across multiple rooms. This often leads to uneven thermal conditions and inefficient energy use in multi-zone residential buildings. This thesis presents a deep reinforcement learning based approach for improving HVAC zoning control through dynamic airflow distribution. A physics based multi zone thermal model of a residential house was developed to simulate heat transfer processes including conduction, convection, solar and internal heat …


Mechanical Performance Of Equilateral Triangular Lattices: The Role Of Nodal Fillets, Fakhreddin Emami, Andrew J. Gross Mar 2026

Mechanical Performance Of Equilateral Triangular Lattices: The Role Of Nodal Fillets, Fakhreddin Emami, Andrew J. Gross

Faculty Publications

Triangular lattices are widely employed for their high strength to weight ratios, yet their mechanical performance is sensitive to geometric features, particularly the nodal geometry. This study investigates the influence of nodal geometry on the mechanical behavior of equilateral triangular lattices across a broad range of relative densities using high fidelity finite element simulations. We characterize the elastic properties, and strength limits as functions of fillet radius. Our results confirm the expected trend that, in stretching-dominated lattices with low relative density, the introduction of fillets reduces both stiffness and buckling resistance. In contrast, at higher relative densities, filleted nodes can …


Mould Risk Prevention In Healthcare Facilities In Hot And Humid Climates Through Acmv Air Supply Parameter Optimisation: Development And Validation Of A Multi-Objective Optimisation Framework, Jiang Kaiyun Mar 2026

Mould Risk Prevention In Healthcare Facilities In Hot And Humid Climates Through Acmv Air Supply Parameter Optimisation: Development And Validation Of A Multi-Objective Optimisation Framework, Jiang Kaiyun

Student Works (2020-2029)

Air conditioning mechanical ventilation (ACMV) supply parameters—such as airflow rate, temperature, and humidity—significantly influence indoor thermal and hygrometric conditions, influencing airflow patterns and mould proliferation. In healthcare facilities, mould poses significant health risks, particularly for immunocompromised patients, contributing to respiratory issues, allergic reactions, and infections. While ACMV systems are central to infection control and indoor air quality, conventional designs often fall short in hot and humid climates. Existing practices typically prioritise high air change rates (ACH) without sufficient dehumidification, underestimate humidity control, and assume spatial homogeneity, overlooking microclimates conducive to localised mould growth. To address these limitations, this research develops …


Marine Vehicle Dynamics Using Koopman Operator Theory With Hybrid Observables, Mikhalib A L Green Mar 2026

Marine Vehicle Dynamics Using Koopman Operator Theory With Hybrid Observables, Mikhalib A L Green

LSU Master's Theses

Accurate modeling of marine vehicle dynamics remains challenging due to strong nonlinear hydrodynamic effects, environmental disturbances, and sensitivity to configuration changes, particularly for small-scale platforms. Classical physics-based models require extensive parameter identification and often exhibit degraded performance outside narrow operating regimes, while purely data-driven approaches may lack structure or impose high computational cost. This thesis presents a data-driven Koopman operator framework with hybrid observables for modeling the dynamics of unmanned marine vehicles. The proposed approach combines structured monomial observables with a learned neural network embedding to construct a lifted state representation in which the nonlinear vehicle dynamics are approximated by …


Mechanical, Thermal And Fire Behaviour Of Hemp-Based Composites With Different Binders For Sustainable Building Applications, Anilcan Aygun, Fahri Birinci, Selim Aytac, Ali Kemal Ayan, Hasan Alp Sahin, Ibrahim Isildak Mar 2026

Mechanical, Thermal And Fire Behaviour Of Hemp-Based Composites With Different Binders For Sustainable Building Applications, Anilcan Aygun, Fahri Birinci, Selim Aytac, Ali Kemal Ayan, Hasan Alp Sahin, Ibrahim Isildak

Journal of Sustainable Construction Materials and Technologies

This study investigates the physical, mechanical and thermal properties of hemp-based composites produced with traditional binders such as lime, cement, gypsum, clay, and water-based glue. Hemp fractions of different sizes (splinter, shiv, fiber and powder) were combined with these binders to manufacture cube and plate specimens, which were tested for physical, mechanical, thermal, and temperature resistance properties. The study aims to compare the mechanical, physical, thermal, and fire behaviour of these composites to assess their suitability for sustainable construction applications. The hemp-based composites were tested for unit weight, water absorption, compressive strength and thermal conductivity. Most specimens are lightweight (<1000 kg/m3), and exhibit good thermal insulation performance and high compressive deformability, making them suitable for seismic-prone regions. The glue-based composite had the lowest unit weight, measured as 330 kg/m3. Thermal conductivity ranged from 0.051 to 0.243 W/m· K, with several mixtures performing better than natural pumice. While cement-based composites showed the highest compressive strength, ranging from 5.5 to 24.8 kg/cm2, natural hydraulic lime is the lowest. Water absorption was high, and moisture release occurred slowly across all hemp fractions. Combustion tests indicated that hemp-based materials have moderate temperature resistance, with charring temperatures ranging from 238–265°C for raw hemp and 300–385°C when mixed with binders. Overall, hemp-based composites are lightweight, eco-friendly, and suitable for non-load-bearing construction and insulation applications. However, improvements in moisture resistance and long-term durability are necessary to enhance their practical applicability.