Engineering Commons^™

Experimental Study Of Graphene Energy Absorbing Layer In Femtosecond Infrared Laser Assisted Bioprinting, Chaoran Dou

Theses and Dissertations

The bioprinting, as a new branch of additive manufacturing, already shown its potential in organ transplantation, medicine develop and personalized medicine. There are three types of bioprinting: droplet based bioprinting, extrusion based bioprinting and laser assisted bioprinting (LAB). Compared with other types of bioprinting, the LAB is the only bioprinting method that does not have a nozzle, which gives it the ability to print high viscosity bioink. The LAB also enjoys higher resolution and cell viability than other methods.

The bubble/jet formation process is the most important process for the LAB, which deposits the bioink to the substrate. To utilize …

An Experimental Thrust Measurement Study On The Nozzle Asymmetry Of Turbulent Pulsed Jets, Cesar Alberto Leos Jr.

Theses and Dissertations

The resurgence of pulsejet engines has renewed the interest of the flow characteristics responsible for the high levels of thrust augmentation that are necessary for Vertical/Short Take-Off and Landing (V/STOL) aircraft. It is well known that pulsation of the engine plays an important role on the thrust performance, but many of the characteristics that are primarily responsible for these enhancements are not well understood. This study is carried out to elucidate the effect of nozzle exit Mach number and the nozzle exit geometry on the characteristics of a high Reynolds number (~105), turbulent free pulsed jet.

Direct thrust measurements are …

Energy Harvesting Using Flextensional Piezoelectric Energy Harvesters In Resonance And Off-Resonance Modes, Mohamed A. Shabara

Mechanical & Aerospace Engineering Theses & Dissertations

Energy harvesting technologies are integrated into various modern devices and systems. These systems include Artificial Intelligence (AI) systems, Internet of Things (IoT), various types of energy harvesters are integrated in many engineering applications such as automotive, aerospace and ocean engineering. In order to develop a fully functioning stand-alone system, it is essential to integrate it with a built in power source such as a battery or a power generator. Also, in many situations, city power sources might not be available. Therefore, reliable, renewable and sustainable local power generators are desired. Piezoelectric energy harvesting (PEH) technologies, which are piezoelectric material-based devices, …

Human Error In Commercial Fishing Vessel Accidents: An Investigation Using The Human Factors Analysis And Classification System, Peter J. Zohorsky

Engineering Management & Systems Engineering Theses & Dissertations

The commercial fishing industry is frequently described as one of the most hazardous occupations in the United States. The objective, to maximize the catch, is routinely challenged by a variety of elements due to the environment, the vessel, the crew, and several external considerations and how they interact with each other. The analysis of fishing vessel accidents can be complicated due to the diverse nature of the industry, including the species caught, the type and size of boat that is employed, how far travelled from their homeport, and the adequacy of the support organizations ensuring safe and uninterrupted operations. This …

A Quest To Identify The Emerging Leadership Skills In Vuca World And Investigation Of Their Applications In Various Organizational Levels And Security Environments, Ali Can Kucukozyigit

Engineering Management & Systems Engineering Theses & Dissertations

The theoretical framework of this research is based on “skills approach” that emphasizes the leader’s capabilities (skills, knowledge, and capabilities) that can be learned, taught, and fostered. VUCA (Volatile, Uncertain, Complex and Ambiguous) environment is chosen as the focal point of this research as the leadership skills are extracted from studies referring to such environment. Although the acronym is dominantly used in management and business domains, the military also uses it to describe the complex operational environments like in Iraq and Afghanistan. The identification of individual leadership skills and delivering the right skill, at the right time, to the right …

Laser Metal Deposition Of An Alcocrfeniti₀.₅ High-Entropy Alloy Coating On A Ti6al4v Substrate: Microstructure And Oxidation Behavior, Wenyuan Cui, Wei Li, Wei Ting Chen, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ti6Al4V has been recognized as an attractive material, due to its combination of low density and favorable mechanical properties. However, its insufficient oxidation resistance has limited the high-temperature application. In this work, an AlCoCrFeNiTi_0.5 high-entropy alloy (HEA) coating was fabricated on a Ti6Al4V substrate using laser metal deposition (LMD). The microstructure and isothermal oxidation behaviors were investigated. The microstructure of as-deposited HEA exhibited a Fe, Cr-rich A2 phase and an Al, Ni, Ti-enriched B2 phase. Its hardness was approximately 2.1 times higher than that of the substrate. The oxidation testing at 700⁰C and 800⁰C suggested that the HEA coating …

Towards Dynamic Vehicular Clouds, Aida Ghazizadeh

Computer Science Theses & Dissertations

Motivated by the success of the conventional cloud computing, Vehicular Clouds were introduced as a group of vehicles whose corporate computing, sensing, communication, and physical resources can be coordinated and dynamically allocated to authorized users. One of the attributes that set Vehicular Clouds apart from conventional clouds is resource volatility. As vehicles enter and leave the cloud, new computing resources become available while others depart, creating a volatile environment where the task of reasoning about fundamental performance metrics becomes very challenging. The goal of this thesis is to design an architecture and model for a dynamic Vehicular Cloud built on …

Dynamic Analysis And Fabrication Of A Bi-Stable Structure Designed For Mems Energy Harvesting Applications., Masoud Derakhshani

Electronic Theses and Dissertations

Thanks to the rapid growth in demand for power in remote locations, scientists’ attention has been drawn to vibration energy harvesting as an alternative to batteries. Over the past ten years, the energy harvesting community has focused on bistable structures as a means of broadening the working frequency range and, by extension, the effective efficiency of vibration-based power scavenging systems. In the current study, a new method is implemented to statically and dynamically analyze a bistable buckled, multi-component coupled structure designed specifically for low-frequency vibration energy harvesting systems in both macro and MEMS-scale sizes. Furthermore, several micro-fabrication steps using advanced …

U.S. Greenhouse Gas Emission Bottlenecks: Prioritization Of Targets For Climate Liability, Alexis Pascaris, Joshua M. Pearce

Michigan Tech Publications, Part 1

Due to market failures that allow uncompensated negative externalities from burning fossil fuels, there has been a growing call for climate change-related litigation targeting polluting companies. To determine the most intensive carbon dioxide (CO₂)-emitting facilities in order prioritize liability for climate lawsuits, and risk mitigation strategies for identified companies as well as their insurers and investors, two methods are compared: (1) the conventional point-source method and (2) the proposed bottleneck method, which considers all emissions that a facility enables rather than only what it emits. Results indicate that the top ten CO₂ emission bottlenecks in the U.S. …

Investigation Of Strength And Fatigue Life Of Rubber Asphalt Mixture, Jiang Yuan, Songtao Lv, Xinghai Peng, Lingyun You, Milkos Borges Cabrera

Michigan Tech Publications, Part 1

Strength and fatigue life are essential parameters of pavement structure design. To accurately determine the pavement structure resistance of rubber asphalt mixture, the strength tests at various temperatures, loading rate, and fatigue tests at different stress levels were conducted in this research. Based on the proposed experiments, the change law of rubber asphalt mixture strength with different temperatures and loading rates was revealed. The phenomenological fatigue equation of rubber asphalt mixture was established. The genetic algorithm optimized backpropagation neural network (GA-BPNN) is highly reliable for optimizing production processes in civil engineering, and it has a remarkable application effect. A GA-BPNN …

Climate Change And Market-Based Insurance Feedbacks, Eric R. Holley, Adam Liska, Cory Walters, Geoffrey C. Friesen, Michael Hayes, Max J. Rudolph, Donald A. Wilhite

Adam Liska Papers

Climatic events have accounted for 91% of $1.05 trillion in insured costs for global catastrophic events from 1980 to 2016. Costs are driven by socio-economic development and increased frequency and severity of climatic disasters driven by climate change. Government policies to reduce systemic risk (e.g., cap-and-trade, carbon tax) have been a predominant approach for mitigation and adaptation. Alternatively, market-based incentives for climate change adaptation and mitigation already operate via the insurance industry to lessen impacts on society. Insurance feedbacks include changes in 1) premiums and insurance policies, 2) non-coverage, and 3) policy making and litigation. Alongside government policies, insurance feedbacks …

Hydrothermal Reaction Synthesis And Characterization Of Zns:Ag Scintillator, Yuchen Shao

All Theses

Thisworkaims at the development of a reactive ultrafiltration membrane scintillator for rapid activity determination and isotopic quantification of waterborne special nuclear materials (SNMs) based on ZnS:Ag. The effects of the pH of the precursor solution on ZnS:Ag synthesized under various conditions of temperature and time by the hydrothermal reaction synthesis method (200℃ for 6 hours, pH from 1 to 12; 100℃ for 2 hours, pH from 7 to 12;60℃ for 6 hours, pH from 7 to 12) were investigated. Samples were characterized on their structure, morphology and luminescence by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), photoluminescence (PL) …

Hydraulic Effects Of Perpendicular Water Approach Velocity On Meter Gate Flow Measurement, John M. Thorburn

Master's Theses

Accurate flow measurement is required to effectively manage water resources. California Senate Bill X7-7 (SB X7-7), legislates this need by requiring agricultural water providers serving areas greater than 25,000 acres to develop an Agricultural Water Management Plan (AWMP) and adopt pricing based at least partly on volumetric water deliveries (DWR, 2009). This study focused on two of the most common flow measurement/flow control devices used in California open channel water conveyance systems: the circular meter gate and the rectangular meter gate. Testing was conducted on three Armco-type (round gates over round discharge pipe) gates measuring 12”, 18”, and 24” and …

Pathfinding Interplanetary Bus Capability For The Cal Poly Cubesat Laboratory Through The Development Of A Phobos-Deimos Mission Concept, Alyssa M. Ralph

Master's Theses

With the rise of CubeSats and the demonstration of their many space applications, there is interest in interplanetary CubeSats to act for example as scientific investigations or communications relays. In line with the increasing demand for this class of small satellites, the Cal Poly CubeSat Lab (CPCL) seeks to develop a bus that could support an interplanetary science payload. To facilitate this, a mission concept to conduct science of the moons of Mars, Phobos and Deimos, is investigated by determining the mission needs for a CubeSat in a Phobos-Deimos cycler orbit through the development of a baseline design to meet …

Boost Converter Inductor Sizing Effects On The Performance Of Mppt Algorithms, Alan Nonaka

Master's Theses

With solar power and other renewables set to take over the market in the coming decades, maximum power point tracking will be essential to optimizing power output. One underserved topic of research is the effect of inductor current ripple on performance of Maximum Power Point Tracking (MPPT) algorithms. Many new topologies are focused on decreasing the ripple from PV source to increase efficiency and power output. However, not much has been done to show ripple degrading performance of MPPT algorithms. This study uses a boost converter topology to test the performance of constant duty cycle step Perturb and Observe (PO), …

Low-Cost Reaction Wheel Design For Cubesat Applications, Nicholas J. Bonafede Jr.

Master's Theses

As science instruments on CubeSats become more sensitive to the attitude of the spacecraft, better methods must be employed to provide the accuracy needed to complete the planned mission. While systems that provide the accuracy required are available commercially, these solutions are not cost-effective, do not allow the design to be tailored to a specific mission, and most importantly, do not give students hand-on experience with attitude control actuators. This thesis documents the design, modeling, and simulation of a low-cost, student-fabricated, reaction wheel system for use in 3U CubeSat satellites. The entire design process for the development of this reaction …

Traffic Privacy Study On Internet Of Things – Smart Home Applications, Ayan Patel

Master's Theses

Internet of Things (IoT) devices have been widely adopted in many different applications in recent years, such as smart home applications. An adversary can capture the network traffic of IoT devices and analyze it to reveal user activities even if the traffic is encrypted. Therefore, traffic privacy is a major concern, especially in smart home applications. Traffic shaping can be used to obfuscate the traffic so that no meaningful predictions can be drawn through traffic analysis. Current traffic shaping methods have many tunable variables that are difficult to optimize to balance bandwidth overheads and latencies. In this thesis, we study …

A Comparison Study Using Particle Swarm Optimization Inversion Algorithm For Gravity Anomaly Interpretation Due To A 2d Vertical Fault Structure, Neil Lennart Anderson, Khalid S. Essa, Mahmoud Elhussein

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A new approach to the inversion of gravity data utilizing the Particle Swarm Optimization (PSO) algorithm is used to model 2D vertical faults. The PSO algorithm is stochastic in nature; its development was motivated by the communal in-flight performance of birds looking for food. The birds are represented by particles (or models). Individual particles have a location and a velocity vector. The location vectors represent the parameter value. PSO is adjusted with random particles (models) and searches for targets by updating generations. Herein, the PSO algorithm is applied to three synthetic data sets (residual only with and without noise, residual …

Effects Of Clay Creep On Long-Term Load-Carrying Behaviors Of Bored Piles: Aiming At Reusing Existing Bored Piles, Lin Li, Weibing Gong, Jingpei Li, Jingpei Li

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An analytical procedure is presented for assessing the long-term load-carrying behavior of bored piles in clay, where the plastic volumetric strain of surrounding clay caused by creep is estimated by an advanced elasto-viscoplastic constitutive model. Two key soil parameters, the undrained shear strength and the shear modulus, which govern the load-carrying behavior of bored piles in clay, are determined from the definition of the quasi-over consolidation ratio and the concept of the critical state theory-based Cam-clay model. The long-term load-carrying capacity of bored piles is evaluated based on the total stress method. Hyperbolic load-transfer models are developed with proper incorporation …

Methods To Investigate Hyperthermia Induced By Tumor Treating Fields, Ruchi Singh

Dissertations and Theses (Open Access)

Tumor Treating Fields (TTFields) are an antineoplastic treatment delivered via application of alternating electric fields using insulated transducer arrays placed directly on the skin in the region surrounding the tumor. TTF’s is a non-invasive application of low-intensity (1-3 V/cm), intermediate-frequency (100-500 kHz) alternating electric fields. The predominant mechanism by which TTFields are thought to kill tumor cells is the disruption of mitosis through the depolymerization of microtubules and interruption of the spindle structure leading to mitotic catastrophe and the formation of non-viable daughter cells. Tumor Treating fields do not stimulate nerves and muscle because of their high frequency, and do …

Wind Uplifting Performance Of Roof-To-Wall Connections And Roof Structures With Elastomeric Adhesives In Light-Frame Wood Buildings, Bilal M. Alhawamdeh

Dissertations

Light-frame wood residential buildings are highly susceptible to damage caused by severe wind events such as hurricanes and tornados. Roof failures in residential buildings are commonly observed due to weaknesses of or missing connections. Roof-to-wall connections not only have significant influences on roof performance but also affect building resistance due to their critical role of transferring wind loads to the wall system and ultimately to the foundation. Roof fails when it has no sufficient wind uplift resistance due to improper selection or installation of construction materials (including fasteners) and strength degradation due to aging or long service. Toenailing is commonly …

Production And Characterization Of Uranium Sol Gel Surrogates Produced With Cerium Acetate And Cerium Nitrate, Matthew Brett Alford

All Dissertations

For the production of ceramic microspheres for future space travel, new methods of processing must be explored. The sol gel method proves promising for the production of uranium-based ceramic microspheres that are consistent enough in size and shape for such an application. A process for producing these microspheres has already been established, but there are avenues for improvement.

Handling of radioactive material like uranium is not always possible or warranted. As such, a non-radioactive surrogate that greatly resembles the processing of its actual radioactive counterpart. Herein this work a cerium-based surrogate is developed to closely resemble an already established process …

Effects Of Process Parameter Variation On The Surface Roughness Of Polylactic Acid (Pla) Materials Using Design Of Experiments (Doe), C. Burke, A. Dalal, A. Abukhalaf, Rafiqul Noorani

Mechanical Engineering Faculty Works

3D Printing (3DP) is an additive manufacturing technology used to rapidly build parts that are designed using 3D modeling software. 3DP builds a part by adding one layer of the working material at a time until the process is complete. One main concern with 3D printed samples is the high levels of surface roughness, which can result in the rejection of parts by many precision manufacturing companies. The objective of this research is to use the Design of Experiment (DOE) to analyze which factors influence the surface roughness of the part built from a 3D printer. In this research, a …

One Dimensional Neural Time Series Generation, Kaleb Earl Smith

Theses and Dissertations

Time dependent data is a main source of information in today’s data driven world.Generating this type of data though has shown its challenges and made it an interesting research area in the field of generative machine learning. The challenge with this one-dimensional (1D) data has been for applications in machine learning to gain access to a considerable amount of quality data needed for algorithm development and analysis. Modeling synthetic data using a Generative Adversarial Network (GAN) has been at the heart of providing a viable solution. Our work focuses on one dimensional times series and explores the “few shot” generation …

Signal Processing Combined With Machine Learning For Biomedical Applications, Md Shakhawat Hossain

Theses and Dissertations

The Master’s thesis is comprised of four projects in the realm of machine learning and signal processing. The abstract of the thesis is divided into four parts and presented as follows,

Abstract 1: A Kullback-Leibler Divergence-Based Predictor for Inter-Subject Associative BCI.

Inherent inter-subject variability in sensorimotor brain dynamics hinders the transferability of brain-computer interface (BCI) model parameters across subjects. An individual training session is essential for effective BCI control to compensate for variability. We report a Kullback-Leibler Divergence (KLD)-based predictor for inter-subject associative BCI. An online dataset comprising left/right hand, both feet, and tongue motor imagery tasks was used to …

A Feature-Based Approach To Function Modeling And Reasoning For Thermal-Fluid Systems Engineering, Lakshmi Narasimhon Athinarayana Venkatanarasimhan

Theses and Dissertations

This research is focused on extending the language of function modeling by developing CAD-like features that are built using primitive functions. These features are reusable units of functions that represent the working principle of a system of higher level of abstraction than the ones of the primitive functions published in prior literature. This approach can be used to also establish an alternate concept/working principle that satisfies the same features, and thus enabling the integration of function models into previously established concept generation programs. It is expected that designers perceive concepts at different levels of abstractions. As a result, the feature-based …

Investigating The Use Of 3d Printing Pens For Additive Manufacturing Component Repair, Kyle Andrew Koren

Theses and Dissertations

The work presented in this thesis provides fundamental research for investigating the application of 3D printing pens for the repair of components manufactured by 3D printers. Test specimens of three different print orientations were 3D printed with acrylonitrile-butadiene-styrene (ABS) and underwent a tensile load test, through rupture, to determine the maximum tensile load experienced. These ruptured specimens were then manually repaired with a 3D printing pen and put through another tensile test to determine the percentage of maximum tensile load retained. The two print orientations that had the axis of tensile load applied parallel to their print layers experienced rupture …

Submerged And Floating Woody Debris-Blocking Sensitivity Of Labyrinth Weirs, Taylor Vaughn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Accumulation of floating and submerged woody debris at flow control structures can result in reduced discharge efficiency (higher upstream head for a given weir discharge). Labyrinth weirs are more prone to debris blockage than less efficient control structures due to their ability to pass large amounts of flow with relatively small heads. Labyrinth weirs also have geometric properties that are more likely to prevent debris from passing over the weir than linear weirs.

A laboratory study was performed to evaluate the interaction between labyrinth weirs and debris sizes. The individual debris tests indicated that debris blockage probability is influenced by …

Improving Hardware Implementation Of Cryptographic Aes Algorithm And The Block Cipher Modes Of Operation, Chu-Wen Cheng

Theses and Dissertations

With ever increasing Internet traffic, more business and financial transactions are being conducted online. This is even more so during these days of COVID-19 pandemic when traditional businesses such as traditional face to face educational systems have gone online requiring huge amount of data being exchanged over Internet. Increase in the volume of data sent over the Internet has also increased the security vulnerabilities such as challenging the confidentiality of data being sent over the Internet. Due to sheer volume, all data will need to be effectively encrypted. Due to increase in the volume of data, it is also important …

Performance Analysis Of V2v And V2i Communications Using Empirical Path Loss Models Indicators And Embedded Iot Devices, Ibrahim Lateef Oraibi Al Kinoon

Theses and Dissertations

Vehicle management technologies deals with the management of critical vehicle information, including location, idle time, speed, and mileage. Such information can always be transferred through a direct vehicle-to-vehicle communication among cars. However, the limitation of this type of design is that it is based on the assumption that vehicles are always served by cellular bases, which is not always the case. For the effective implementation of the Internet-of-Things (IoT) technology in this sector, it is critical to design vehicles with systems that enable them to transmit essential information in the absence of base stations. IoT technologies can then be used …