Engineering Commons^™

Head Impact Effects In Small Remotely Piloted Aircraft System (Srpas) Collisions: Gender Specific Risks And Vulnerable Population Protection, Md Farhan Hoque Sagar

Electronic Thesis and Dissertation Repository

This study focuses on supporting the development of safety regulations for vulnerable populations during drone to head impacts. First, the small female head and neck model was compared to cadaveric data. Then, combined with lab’s previous work, gender-based disparities in head impact responses were highlighted, with small females experiencing higher injury risk metrics, despite lower skull von Mises stress. Beyond small females, children of various ages and their head responses during impacts were also analyzed. In addition to the previously developed quadcopter drone model, a new Mavic Pro drone model was developed, and this model was integrated with human head …

Experimental And Simulation Study Of Reactive Silver Ink Droplet Evaporation, Weipeng Zhang

Electronic Thesis and Dissertation Repository

The evaporation of particle-free silver ink droplets on heated substrates directly impacts the morphology of the resultant silver particles and films. In this thesis, COMSOL Multiphysics simulations of the solvent (water-ethylene glycol mixture) droplet evaporation process are used to explain the microflows, mass transfers, and heat distribution responsible for the experimental observations. The reactive ink incorporates fluoro-surfactant FS-31 and poly (acrylamide) (PAM) to suppress the coffee-ring effect that negatively impacts the electrical conductivity. Experiments show that the droplet evaporation process results in varied silver particle morphology, depending on the locations within the droplet, leading to uneven surfaces. Large particles (3 …

Numerical Modeling And Simulation On Deformation And Failure Behaviors Of Polymeric Materials, Heng Feng

Electronic Thesis and Dissertation Repository

Featured by biocompatibility, high compliance and capacity in sustaining large deformation, dielectric elastomers (DEs) and hydrogels have gained extensive research popularity for their potential applications in the fields of soft robots, biomimetics, tissue engineering, drug delivery, and energy harvesting. The design of such soft and smart material-based devices and structures requires deep understanding and accurate simulation of their constitutive behaviors, which is challenged by their nonlinear material properties due to unique microstructures and multi-physics coupling. Meanwhile, in different application contexts, those structures are also susceptible to different failure modes, imposing further challenges in simulating and predicting their performance. To fulfill …

Effect Of Ion Irradiation On The Rate Dependence Of Plastic Deformation Of Extruded Zr-2.5%Nb, Konrad P. Mazurkiewicz

Electronic Thesis and Dissertation Repository

The purpose of this thesis is to examine the properties of Zr-2.5%Nb pressure tube material in the transverse direction. Through testing at room temperature, material properties such as the strain hardening, strain rate sensitivity and apparent activation volume were investigated. The effects of Zr⁺ ion-implantation occurring at 300°C, simulating irradiation-induced damage, and the strain rate of loading on these properties were also investigated.

Two methods of testing were performed: in-situ micro-pillar compressions and nanoindentation testing. Ion-implantation was observed to increase material strength and hardness. However, certain implanted micro-pillars displayed early localized failure that reduced strength. This finding warrants further …

Use Of Electrochemical Techniques And Statistical Analysis To Investigate The Pitting Probability Of Copper, Sina Matin

Electronic Thesis and Dissertation Repository

The development of a safe permanent disposal plan is essential for the long-term disposal of used fuel bundles. Nuclear Waste Management Organization (NWMO) has been investigating the deep geologic disposal of nuclear waste which offers the optimum passive safety system with a negligible probability of release of radionuclides into the environment.

The proposed used fuel containers (UFC) for the permanent disposal of high-level nuclear waste in Canada is comprised of a carbon steel vessel coated with a 3 mm corrosion-resistant copper layer deposited using a combination of electrodeposition and cold spray deposition. Although copper is often considered to be thermodynamically …

Development Of Pulsed Laser Deposited Tio2, Zno And Azo Thin Uv-Protection Films For Enhanced Perovskite Photostability, Kate Lochhead

Electronic Thesis and Dissertation Repository

Perovskite solar cells are an emerging sustainable energy conversion technology with the potential to provide relief from the global energy crisis. However, the UV-induced degradation of perovskites has been a barrier to commercialization. Thin film encapsulation represents a promising solution for extending device lifetimes. Three materials with suitable bandgaps for blocking UV light are identified: TiO₂, ZnO and AZO. Herein, the optical properties of TiO₂, ZnO and AZO thin films grown by room-temperature pulsed laser deposition are optimized by varying the oxygen partial pressure during deposition. UV-Vis spectroscopy reveals facile bandgap tuning via the concentration of …

Mechanical Property Of Body-Thoroughly Enhanced Austenitic Stainless Steel And High-Mn Steel By Industry-Applicable 3-Axis Stress-Released Impact, Busheng Zhang

Electronic Thesis and Dissertation Repository

As two important austenitic steels, the austenitic stainless steel (SS) and austenitic high-Mn steel have been seeking a decent yield strength to match their versatile exceptional advantages. However, the traditional, severe, and high-strain-rate plastic deformation techniques currently used to strengthen the austenitic steels, are limited by their ability to produce ultrastrong steel, bulk sized steel, and the fracturing risk they pose to the steel, respectively. In this research, we propose an industry-applicable 3-axis stress-released impact process, which addresses the challenges facing the current techniques and successfully prepares the body-thorough ultrastrong and ductile austenitic steels without fracturing risk.

The bulk 316L …