Digital Commons Network^™

Deep Learning For Predicting Impact Energy And Compression After Impact Strength Of Composite Materials Using C-Scan Images, K. T. Tan, Jason P. Mack, Faizan Mirza, Zhong-Hui Duan

University Research

Traditional assessment of post-impact performance in carbon fiber reinforced polymer (CFRP) composites often relies on simplified scalar metrics that fail to capture the complex spatial interactions driving failure. This study addresses this limitation by developing an automated, end-to-end deep learning framework that shifts from manual feature extraction to the direct interpretation of raw damage morphology from ultrasonic C-scans. Using a ResNet18-based convolutional neural network (CNN) trained on 1,428 augmented images, the model achieved coefficients of determination (R2) of 0.7948 ± 0.0847 for compression after impact (CAI) strength and 0.9436 ± 0.0098 for impact energy. Beyond prediction, this dual-purpose methodology serves …

Development Of A Simulation-Driven Evaluation System For Foreign Objects In Aircraft Structures, Daniela Garcia

Open Access Theses & Dissertations

This thesis investigates the use of simulation-driven methods to evaluate the behavior and potential impact of foreign objects within aircraft structures. Foreign Object Damage (FOD) remains a major concern in aerospace safety, as small components unintentionally left inside aircraft compartments can create uncertainty regarding their effect during flight. Although current inspection methods can detect the presence of foreign objects (FOs), they often cannot determine whether these objects pose a significant structural risk, leading to conservative maintenance decisions. To address this limitation, this work develops a simulation-based framework that integrates Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) to evaluate …

Experimental Investigation Of A Shrouded Dual-Rotor Wind Turbine For Small-Scale Applications, Ahmed Elbaz, Mahmoud Alghrieb Mr

Mechanical Engineering

Small-scale wind power faces significant challenges in areas characterized by low wind speeds and turbulent wind patterns, limiting its contribution to the global energy demand. To spread the use of wind energy even at regions of low wind speeds, the turbine with wind lens concept was introduced in the literature. This device increases the free stream wind speed at the turbine section which enhances power output of the turbine. Other methods involved using dual rotors to augment power output of the turbine too. In the current study, the performance of single and dual rotors was investigated using wind lens to …

Comparative Experimental Analysis Of Vertical And Inclined Bifacial Pv Panels Under Varying Azimuthal Angles In Egypt For Agrivoltaics Systems, Ahmed Elbaz, Yahia Hassanein Nr, Iman Elmahallawi Dr, Tarek Abdelsalam Dr

Mechanical Engineering

The growing deployment of photovoltaic (PV) technologies across a wide range of applications, from residential rooftops to agrivoltaic systems, has created new opportunities, such as harnessing albedo from bright surroundings, as well as challenges, including limited space availability and adverse shading effects, which urge the need for optimising space along with energy use. While vertical bifacial photovoltaic (VBPV) systems may offer a potential solution, their effectiveness against their conventional inclined counterparts remains largely unexplored in different locations. This paper presents an experimental evaluation of the energy performance of vertical and inclined Bifacial PV configurations under the different climatic conditions of …

Technology Based Assessment Of Workplace Biomechanical Risk: A Roadmap For Process Improvement, Tamer Adel Mohamed, Noha Mostafa, Ahmed Elsayed

Mechanical Engineering

The main objective of this paper is to develop a methodology for assessing the biomechanical risk in the workplace and design and apply improvements to reduce this risk by redesigning the working process. The risks are measured using Ergonomics tools to assess body posture and lifting index. Kinect sensor and video recordings are utilized to evaluate the joints' positions as an input for body posture data. Then, the specialized CATIA V5 software [26] is used to simulate the workers' bodies in the form of 3D models. Risk factors were assessed, and a new design was developed to be implemented in …

Cylindrical Versus Spherical Self-Similar Capillary Cavity Collapse, Karl Cardin, Christophe Josserand, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Drop tower experiments have been performed to study the capillary collapse of large high-aspect-ratio cavities. Cavities are formed by momentarily impinging the free surface of a liquid bath with a jet of air in the microgravity environment of a drop tower. The collapse may give rise to a jet and three distinct jetting regimes are identified. Simulations are performed to further investigate the phenomena. The abrupt emergence of a thin high velocity jet is observed experimentally and numerically at a specific initial cavity aspect ratio. Different power laws are identified in different regions of the cavity during the collapse providing …

Optimization Of A Point Absorber Wave Energy Converter (Wec), Rutwa Dilipkumar Nagar

Electronic Theses and Dissertations 2020 - Present

This study examines the performance and optimization of a point absorber wave energy converter with a partially submerged spherical float. A comprehensive open-source computational framework integrates frequency-domain hydrodynamic analysis with time-domain simulation using Capytaine, BEMIO, and WEC-Sim. Hydrodynamic coefficients such as added mass, radiation damping, and excitation forces are calculated and integrated into the governing equation of motion using the Cummins formulation. A parametric analysis varies the float diameter and geometric configurations across several cases. Hydrodynamic coefficients and response amplitude operators are assessed to analyze system behavior and resonance characteristics. Results indicate consistent trends in normalized added mass, with radiation …

Evaluation Of Quantification Methods Applied To Overlapping Ftir Features, Benjamin P. Diehl

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Quantifying overlapping FTIR spectral features is critical for electrochemical analysis but often requires complex deconvolution. This work systematically evaluates several area ratio and proxy-based quantification methods using a controlled synthetic spectral model with varying signal-to-noise ratio, peak spacing, width, background, and data resolution. Constrained peak fitting and fixed-window integration consistently exhibit near-perfect monotonicity (Spearman ≈ 1.000) and linearity (Pearson ≈ 0.999–1.000) across all conditions. In contrast, derivative and moment-based metrics show sensitivity to peak overlap, width, and background. These results demonstrate that physically grounded area-based methods provide the most robust and reliable quantification of overlapping FTIR features.

External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Turbulence in wall-bounded flows governs momentum transport, drag, and energy efficiency in a wide range of engineering systems, yet its response to external forcing remains incompletely understood across transitional and high Reynolds number regimes. This dissertation investigates an active flow control strategy based on spanwise external forcing and demonstrates how it modifies the dynamics of transitional and turbulent channel flows with the objective of identifying the mechanisms through which forcing alters transition, flow physics, and turbulent drag reduction.

Firstly, direct numerical simulations are performed to examine the subcritical transition under external forcing. The onset and sustenance of turbulence are shown …

Vacuum Modification Of The Surface Properties Of T15k6 Hard Alloy By Plasma–Chemical Synthesis Of Tin-Cu Coatings, Aleksandr Semenov, Dmitriy Tsyrenov, Nikolay Ulakhanov, Irina Semenova, Undrakh Mishigdorzhiyn, Wen Ma, Simon C. Tung, George E. Totten

Mechanical and Materials Engineering Faculty Publications and Presentations

The design and main parameters of a plasma–chemical reactor containing two compartments are presented. One compartment houses a vacuum-arc evaporator, while the other houses a planar magnetron. The compartments are separated by a diaphragm with a dosing slot for injecting copper vapor into the TiN synthesis compartment. The conditions for the synthesis of superhard TiN-Cu composite coatings are experimentally determined. Based on established process parameters for TiN synthesis in a nitrogen-containing plasma by Ti evaporation using a vacuum-arc discharge, it is proposed to apply TiN-Cu coatings by injecting Cu vapor into the TiN synthesis area and sputtering Cu using a …

Automatic Determination Of Mechanical Properties From Molecular Dynamic Stress-Strain Curves Using Regression Fringe Response, Josh Kemppainen, Tristan Muzzy, Travis Wavrunek, Gregory Odegard

Michigan Tech Publications

Molecular dynamics (MD) simulations have become a powerful tool for studying polymers, designing new materials, and composites. Mechanical behavior in MD simulations are typically evaluated through stress-strain curves. However, MD-generated stress-strain curves are often obscured by thermal noise from atomic vibrations. This noise complicates the reliable derivation of mechanical properties and hinders objective and reproducible analysis. The noise in the stress-strain curves has been removed by using a Butterworth low-pass filter, enabling clearer interpretation of stress-strain data. Building on this, a novel analysis framework the Regression Fringe Response (RFR) is introduced to systematically determine the Young's modulus, yield strength, and …

Analysis For Predicting Surface Temperature And Combustion Of Heavy-Duty, Pre-Chamber-Enabled, Hydrogen Engines, Tony Spezia

Master's Theses (2009 -)

Hydrogen as an alternative fuel shows great promise to help reduce greenhouse gas emissions from heavy duty engines. However, the challenge for hydrogen engines is that hydrogen has very different combustion properties compared to conventional hydrocarbon fuels. Hydrogen has very high flame speeds, very low ignition energy, and very wide flammability limit. These properties result in hydrogen engines being prone to abnormal combustion. Abnormal combustion makes hydrogen engines difficult to control or can cause catastrophic damage to the engine, so it is important to avoid conditions where abnormal combustion occurs. Hot spots along the combustion chamber walls are often the …

Techno-Enviro-Economic Analysis Of Precipitated Calcium Carbonate Production From Carbon Dioxide In Cement Industry Flue Gas And Calcium Hydroxide, Natalia Debora Panggabean, Widodo Wahyu Purwanto

Journal of Materials Exploration and Findings

CCUS is a technological solution to reduce emissions from the cement industry, which is the second largest CO2-intensive industry. This study aims to analyze technical, economic, and environmental performance of Precipitated Calcium Carbonate (PCC) synthesis in cement industry flue gas. The process simulation includes the CO2 capture system from cement plant, CO2 captured used as feedstock for PCC synthesis process through its reaction with calcium hydroxide. The simulation was carried out using ASPEN Plus software. Technical analysis was performed to determine the CO2 capture efficiency and PCC synthesis efficiency. Economic analysis was conducted to calculate CO2 capture cost and production …

Feasibility Analysis Of Thermal Oxidizer To Determine Remaining Life Using Fitness- For-Service Level 3 Method, Yudhi Yudistirawan, Donanta Dhaneswara, Wahyuaji Narottama Putra, Gama Widyaputra, Dewi Kurnia Suci, Agung Putra Mahardhika

Journal of Materials Exploration and Findings

An aged thermal oxidizer (TOX) in the oil and gas industry necessitates a comprehensive evaluation to ensure its continued safe operation. This study presents a Remaining Life Assessment (RLA) and a Fitness for Service (FFS) evaluation for the four main components of the TOX, in accordance with API 510, API 579/ASME FFS-1, and ASME BPVC Section VIII Div-1 standards. The investigation includes the determination of maximum stress and maximum temperature required to assess the operational viability of the reactor. The four components are radiant, convection, transition, and stack sections—were modeled using the finite element method (FEM). Following the geometric modeling, …

Assessing Passenger Electric Vehicle Growth Strategies And Their Impacts On Electricity Demand Load And Co2 Emissions In Aceh Province To Achieve Net Zero Emission Target By 2060, Taufik Hidayat, Widodo Wahyu Purwanto

Journal of Materials Exploration and Findings

The electrification of the transport sector is a crucial pathway for achieving Indonesia’s Net Zero Emissions (NZE) target by 2060. This study assesses the potential impact of passenger electric vehicle (EV) penetration on electricity demand and CO2 emissions in Aceh Province through a scenario-based modelling approach. Two policy-aligned scenarios are assessed: a low-penetration (LP) scenario and a high-penetration (HP) scenario. Using the Gompertz model and the ASIF framework, total CO2 emissions were projected from 2020 to 2060. Results show that although higher EV penetration reduces direct emissions from internal combustion engine (ICE) vehicles, total CO2 emissions increase more significantly under …

Leveraging Convolutional Neural Networks For Through-The-Wall Radar Imaging: Challenges, Impacts, And Future Directions, Tumaini Edgar, Abdulla F. Ally, Abdi T. Abdalla

Tanzania Journal of Engineering and Technology (TJET)

Through-the-wall radar imaging (TWRI) is an essential technology for military and rescue applications; however, its performance in detecting and visualizing high-quality images of targets behind walls is significantly degraded by multipath reflections and signal attenuation. This paper reviews the current state of TWRI and its challenges, and explores the transformative potential of deep learning, particularly convolutional neural networks (CNNs), in addressing these challenges. Peer-reviewed articles published from 2018 to 2024 were analysed to examine CNN applications in addressing TWRI challenges. The analysis reveals that using CNNs, TWRI systems can be more effective by filtering wall distortions, reducing noise, lowering computational …

Implementation Of The Fourth Industrial Revolution Technologies In Tanzania’S Downstream Oil And Gas Industries, Vitalis John Mwinyi

Tanzania Journal of Engineering and Technology (TJET)

The advent of the fourth industrial revolution (IR4.0) has resulted in the digital transformation of multiple sectors of the economy due to the disruptive nature of the technologies driving the revolution. The technologies have already found their way into the oil and gas industries across the globe, especially in upstream, midstream, and downstream operations. However, the degree of implementation is not the same for these operations, considering the complexities involved, integrated process, the associated risk and investment cost, among others. This study aimed to establish the implementation level of IR4.0 technologies in the downstream operations. A survey method was employed …

Acoustic Response Of The Cnt-Reinforced Multilayered Acoustic Foam Composites (Mafc), Trey Brauch

Electronic Theses and Dissertations 2020 - Present

Acoustic metamaterials are engineered materials designed to control and manipulate sound propagation. Many such systems incorporate acoustic foams due to their porous structure, low density, and high specific surface area, which promotes efficient sound absorption. However, a major limitation of conventional acoustic foams -particularly open-cell varieties- is their lack of waterproofing, rendering them unsuitable for underwater or moisture-prone environments. To address this limitation, a multilayered acoustic foam composite (MAFC) was developed as a lightweight, waterproof structure with enhanced sound absorption performance. The MAFC consists of five layers: the first and fifth layers are aluminum foam, providing structural integrity; the second …

Three Degree Of Freedom Wave Energy Converter Design For Resonant Motion, Greg Ballen, David G. Wilson, Rush Robinett, Shangyan Zou, Wayne Weaver

Michigan Tech Publications

As multiple-degree-of-freedom (3-DOF) wave energy converters (WECs) have demonstrated the ability to produce more power than single-degree-of-freedom devices, the challenge of designing buoys for efficient energy harvesting has increased in complexity. In this paper, a cylindrical WEC is designed to naturally resonate in surge, pitch, and heave modes at a specific target frequency of 0.2 Hz. By utilizing a penalty-based optimization method to balance buoyancy requirements with natural resonance, the design achieves minimal control force input, thereby reducing fluctuations in energy output and local energy storage requirements. The performance is evaluated under irregular sea states using a Bretschneider spectrum. Results …

Development Of An Experimental Platform For Hydrogen-Propelled Cold Spray, Michael James Katz

Theses and Dissertations

Cold spray (CS) has gained recent interest as an additive manufacturing process. This process uses high pressure propellant gas to accelerate solid-state powder particles through a specialized nozzle, beyond which the powder deposits onto a substrate as a dense coating and without either material undergoing a phase change. Both nitrogen (N2) and helium (He) are commonly used as CS propellants, with He generally yielding superior results at otherwise similar processing conditions. However, performance advantages of He come with a significant drawback: He is a limited resource that may be sensitive to geopolitical conflicts and, in recent history, has been subject …

Hypersonic Impact Method For Aerodynamics And Convective Heating (Hi-Mach) With Sensitivities, Jeremiah Goates, Logan Freeman, Nathan Hoch, Douglas Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

The purpose of this paper is to present the development of an engineering level code for calculating hypersonic aerodynamics and convective heating, HI-Mach. Novel to this paper are the use of analytic methods for streamline tracing and the direct differentiation of geometric sensitivities for both forces and heat load. Independent panel inclination methods calculate the pressure distribution on the surface of a hypersonic vehicle. Normal shock relations provide the thermodynamic state on each panel. Streamlines are integrated using closed-form streamline equations. Flat plate formulas corrected for compressibility calculate the skin friction coefficient and acreage heat flux on each panel. Formulas …

Further Development Of A Low-Energy Arc-Ignition System For Nytrox/Abs Hybrid Propulsion Systems, Stephen A. Whitmore, Jared S. Coen, Ryan J. Thibaudeau

Mechanical and Aerospace Engineering Faculty Publications

Utah State University has developed a high-performance “green” hybrid propulsion technology based on the unique electrical breakdown properties of 3D-printed acrylonitrile butadiene styrene. Using 3D-printed ABS as fuel, typical startup sequences require approximately 5–15 joules and, once started, the system can be sequentially fired with no additional energy inputs required. The number of possible ignitions is limited only by the amount of fuel. The most technologically mature version uses gaseous oxygen (GOX) as oxidizer and 3D-printed ABS as fuel. While GOX is mass-efficient, it lacks volumetric efficiency unless highly pressurized. Nytrox, a blend of GOX and nitrous oxide, improves propellant …

Implantable, Sensor-Embedded Vascular Graft Towards Wireless Monitoring Of Stenosis, Nnamdi Dike

LSU Master's Theses

Arteriovenous (AV) grafts are commonly used to provide vascular access for hemodialysis in patients with end-stage renal disease. Despite their widespread use, AV grafts are prone to complications such as stenosis and thrombosis. Early detection of these conditions remains challenging with current monitoring methods too costly or insufficient. This work presents the design, fabrication, and validation of an LC pressure sensor embedded within a model AV graft to enable real-time monitoring. The proposed system integrates a parallel-plate capacitive pressure sensor with a spiral inductor to form an LC circuit embedded within an elastomeric graft wall. The Ecoflex 00-30 dielectric layer …

On The Drainage Vortices Of Liquid In A Container With Two Outlets, Radivoje Stankovic

Electronic Theses and Dissertations 2020 - Present

Vortices that form over multiple drainage ports may exhibit a distinct, periodic alternating behavior, whereby the air core moves periodically between different drainage ports. The physical processes which govern this behavior have not yet been explained, despite the widespread and thorough attempts to describe the flow of water through single or multiple outlets. Early experiments on the alternating behavior of this vortex resulted in a nondimensional relation between the alternating frequency and water height and container geometry with an R2 = 0.91. Subsequent 2D PIV measurements of the flow were performed at different laser heights of 25 mm and 128 …

Mathematical Modelling And Optimisation Of The Reactor For The Esterification Process Of Safflower Oil With N-Butyl Alcohol, Sadritdin Makhamatdinovich Turabdjanov Academician, Hasan Sadriddin Ugli Fozilov, Ozoda Bakhronovna Axmedova, Sadriddin Fayzullayevich Fozilov

Technical science and innovation

This study addresses the mathematical modelling and optimisation of a reactor for the esterification of safflower oil with n-butyl alcohol. To improve process controllability and reduce the need for numerous pilot-scale trials, an ideal-mixing continuous stirred-tank reactor (CSTR) model was adopted. Incorporating reaction kinetics, the effect of contact time on the relative viscosity of the product mixture was analysed. The modelling results indicate that achieving an acceptable degree of feedstock conversion is difficult when a single ideal-mixing reactor is used. Therefore, a CSTR cascade was proposed, and the configuration with N = 2 reactors was selected as the most appropriate …

Manufacturing Of Functional Surface Coatings In The Automotive Industry, Gulirano Saidakhmedova

Technical science and innovation

The development of environmentally sustainable technologies for material processing represents one of the most pressing scientific and technical challenges in modern industrial production. This issue is particularly relevant to the automotive industry, where growing demands for energy efficiency, durability, and environmental safety necessitate the adoption of advanced manufacturing methods. Special attention is given to developing vacuum-based, import-substituting equipment and technologies for producing functional coatings from composite materials with predefined physical, mechanical, and optical properties, including reflective and protective characteristics. Current requirements for mechanical engineering products and production technologies drive the need for innovative approaches to material processing and specialized technical …

Theoretical And Practical Foundations Of Healthcare System Digitalization, Sanjarbek Bekturdiev Sharifboyevich Phd, Muxlisa G‘Ulom Qizi G‘Ofurova

Technical science and innovation

The digital transformation of healthcare represents a key direction in improving the accessibility, quality, and efficiency of medical services. This study examines the main components of eHealth, including telemedicine, electronic health records, cloud technologies, and mobile applications, as well as the role of international organizations in promoting national digital health strategies. Particular attention is given to the current state of digital healthcare in the Republic of Uzbekistan, where significant progress has been made in developing infrastructure and implementing information systems, although challenges related to integration, standardization, and regulatory support remain. The work identifies the main trends in the development of …

Development Of New Methods For Calculating Pressure And Energy Losses For Pumping Station Water Intakes, Faxriddin Jaylovovich Nosirov, Oleg Yakovlevich Glovatsky, Jurabek Abdyrahmon O'G'Li Urolov, Abduqodirkhon Samatkhonovich Abdullakhaev, Anvar Mamur Ugli Uzokov

Technical science and innovation

The aim of this study is to improve the efficiency of water resource management methods. Improvements to the water intake of the Karshi Main Canal are considered using calculations of pressure losses at the entry and exit of liquid into the flow, which differ from pressure losses in a stationary medium. The article considers some of the methods for using renewable energy sources, where the change in gravitational potential energy does not depend on the way of using energy and the operating scheme is a gravitational energy pump. The implementation of control and monitoring systems is necessary to ensure optimal …

Refinement Of Wind Speed Estimation At Turbine Hub Height Using Satellite Data And Regression Analysis Under Complex Terrain Conditions, Isroil Abriyevich Yuldoshev, Tulqin Rustamovich Jamolov, Sa'dullo Sayfiddin Ugli Fazliddinov, Jumanazar Farhodjon OʻGʻL Abdurashidov

Technical science and innovation

Reliable assessment of wind energy potential in regions characterized by complex terrain is often constrained by the limited availability of ground-based meteorological measurements. This study proposes an improved regression-based approach for refining wind speed estimates at the wind turbine hub height of 65 m using satellite-derived data from the NASA POWER database combined with a logarithmic vertical wind profile. The proposed methodology is validated using real operational data from a 750 kW wind power plant located in the mountainous Bostanlyk district of Uzbekistan for the period 2018–2021. The regression analysis demonstrates a strong linear relationship between the extrapolated wind speed …

Tunable Shock And Vibration Damping In Metal Laser Powder Bed Fusion Components Via Controlled Post-Print Compaction Of Particle Damper Cavities, Joud N. Stame, Yanzhou Fu, Samuel Roberts, Austin Downey, Tianyu Zhang, Lang Yuan, Daniel Kiracofe

Faculty Publications

Components manufactured by Laser Powder Bed Fusion (LPBF) can incorporate particle dampers (PDS) by retaining unfused powder within internal pockets, providing inherent vibration suppression without added mass or separate damping components. This study investigates the damping performance of such LPBF-integrated PDs through two complementary approaches: (1) quantifying the effect of post-printing volume compression on energy absorption by mechanically indenting the damper pocket, and (2) evaluating how variations in particle packing density influence the dynamic response under both sinusoidal and transient impulse excitation. Experimental results from shaker and shock testing demonstrate that increased packing density, whether by compression or tighter confinement, …