Engineering Commons^™

Estimation Of Spacecraft Attitude Motion And Vibrational Modes Using Simultaneous Dual-Latitude Ground-Based Data, Zachary William Henry

Doctoral Dissertations and Master's Theses

Cutting-edge Space Situational Awareness (SSA) research calls for improved methods for rapidly characterizing resident space objects. In this thesis, this will take the form of speeding up convergence of spacecraft attitude estimates, and of a non-model-based approach to the detection of vibrational modes. Because attitude observability from photometric data is angle-based, dual-site simultaneous photometric observations of a resident space object are predicted to improve the convergence speed and steady-state error of spacecraft attitude state estimation from ground-based sensor data. Additionally, it is predicted that by adding polarimetric data to the measurements, the speed of convergence and steady-state error will be …

Computational Solutions Based On Bayesian Networks To Hierarchize And To Predict Factors Influencing Gender Fairness In The Transport System: Four Use Cases, Gemma Dolores Molero, Sara Poveda-Reyes, Ashwani Kumar Malviya Ashwani Kumar Malviya, Elena García-Jiménez, Maria Chiara Leva, Francisco Enrique Santarremigia

Articles

: Previous studies have highlighted inequalities and gender differences in the transport system. Some factors or fairness characteristics (FCs) strongly influence gender fairness in the transport system. The difference with previous studies, which focus on general concepts, is the incorporation of level 3 FCs, which are more detailed aspects or measures that can be implemented by companies or infrastructure managers and operators in order to increase fairness and inclusion in each use case. The aim of this paper is to find computational solutions, Bayesian networks, and analytic hierarchy processes capable of hierarchizing level 3 FCs and to predict by simulation …

Additive And Interface Engineering Of Lead-Tin Mixed Low-Bandgap Perovskite Solar Cells For Higher Efficiency And Improved Stability, Nabin Ghimire

Electronic Theses and Dissertations

Lead (Pb) -Tin (Sn) mixed perovskites suffer from large open-circuit voltage (VOC) loss due to the rapid crystallization of perovskite film, creating Sn and Pb vacancies. Such vacancies act as defect sites expediting charge carrier recombination, thus hampering the charge carrier dynamics and optoelectronic properties of perovskite films. In the first project, we focused on the passivation of perovskite surface defects to increase the opencircuit voltage of the 1.25 eV low-bandgap perovskite solar cells by utilizing a trace amount of Phenethylammonium iodide (PEAI) in the perovskite precursor solution as a doping agent. The incorporation of PEAI in perovskite precursors improved …

Bio-Inspired Materials For Electrochemical Sensors, Matthew Joseph Hummel

Electronic Theses and Dissertations

Electrochemical biosensors are a rapidly growing research area that has greatly improved its specificity, accuracy, and precision in the detection of biomolecules in contemporary literature and industry alike. Typically, these systems exist in a three-electrode conformation with a working electrode functioning as the anode, a counter electrode functioning as the cathode, and a reference electrode allowing for the control of potential in the system. The method by which these sensors work is through the sharing of electrons via redox reactions with the target molecule and the working electrode or modifications on its surface. By exploiting the function of biomaterials that …

Measurement Of Micro Burr And Slot Widths Through Image Processing: Comparison Of Manual And Automated Measurements In Micro‐Milling, Fatih Akkoyun, Ali Ercetin, Kubilay Aslantas, Danil Yurievich Pimenov, Khaled Giasin, Avinash Lakshmikanthan, Muhammad Aamir

Research outputs 2014 to 2021

In this study, the burr and slot widths formed after the micro‐milling process of Inconel 718 alloy were investigated using a rapid and accurate image processing method. The measurements were obtained using a user‐defined subroutine for image processing. To determine the accuracy of the developed imaging process technique, the automated measurement results were compared against results measured using a manual measurement method. For the cutting experiments, Inconel 718 alloy was machined using several cutting tools with different geometry, such as the helix angle, axial rake angle, and number of cutting edges. The images of the burr and slots were captured …

Automated Waterloo Rubric For Concept Map Grading, Shresht Bhatia, Sajal Bhatia, Irfan Ahmed

School of Computer Science & Engineering Faculty Publications

Concept mapping is a well-known pedagogical tool to help students organize, represent, and develop an understanding of a topic. The grading of concept maps is typically manual, time-consuming, and tedious, especially for a large class. Existing research mostly focuses on topological scoring based-on structural features of concept maps. However, the scoring does not achieve comparable accuracy to well-defined rubrics for manual analysis on the quality of content in a concept map. This paper presents Kastor, a new method to automate the Waterloo Rubric of scoring concept maps by quantifying the rubric’s quality assessment parameters. The evaluation is performed on a …

Cybersecurity Analysis Of Load Frequency Control In Power Systems: A Survey, Sahaj Saxena, Sajal Bhatia, Rahul Gupta

School of Computer Science & Engineering Faculty Publications

Today, power systems have transformed considerably and taken a new shape of geographically distributed systems from the locally centralized systems thereby leading to a new infrastructure in the framework of networked control cyber-physical system (CPS). Among the different important operations to be performed for smooth generation, transmission, and distribution of power, maintaining the scheduled frequency, against any perturbations, is an important one. The load frequency control (LFC) operation actually governs this frequency regulation activity after the primary control. Due to CPS nature, the LFC operation is vulnerable to attacks, both from physical and cyber standpoints. The cyber-attack strategies ranges from …

Tensile Environment Chamber, Cameron Ngai, Trent Hamilton, Mitchell Carroll, Jack Molitor

Mechanical Engineering

This project created the heating system, cooling system, and control system for an environmental chamber for a tensile test machine in the Cal Poly Composites Lab. This chamber allows for students to test material properties under a variety of thermal conditions. This project was done in collaboration with a team working on the structural aspect of the chamber. While consumer environmental chambers are on the market, they often cost more than $50,000. Additionally, our chamber conforms to further size and weight constraints. Because of this constraint, many conventional techniques and components used for these chambers are not feasible for our …

Dual Motor Drive System For Formula Sae Electric Race Car, Bryan D. Neill, Jackson T. Mcfaul, Cole T. Andrews, Isaiah D. Penzell

Mechanical Engineering

This paper serves as the Final Design Report (FDR) for the senior project developed by our team. This FDR builds on our CDR, in which the main deliverable was the detailed design of a planetary gearbox delivering a 5:1 reduction to be mated to an Emrax 188 motor. This planetary gearbox would allow for the possibility of implementing a dual-motor torque-vectoring rear-wheel-drive system in Cal Poly Racing’s electric FSAE car, which has demonstrated in simulation to yield significant performance gain over the current single motor/mechanical LSD system. As this project’s scope is purely mechanical, the intent is for the Cal …

Wind Tunnel Data Acquisition System Development Using Labview, Riley Bishop

Mahurin Honors College Capstone Experience/Thesis Projects

Utilizing an educational-purpose wind tunnel, a data acquisition system through LabVIEW was created to experimentally analyze the aerodynamic forces experienced by objects in uniform external flow by automatically performing trials and interpreting electrical measurement signals. To verify experimental results from pressure distribution data around an object, a force balance was designed to mount objects stationarily in the wind tunnel test section while directly measuring the total lift and drag forces, calculating the pitching moment (for airfoils), and monitoring the angle of attack. The force balance design includes three load cells, one for measuring drag force and two for measuring total …

Synthesis And Catalytic Properties Of Metal-Organic Frameworks Mimicking Carbonic Anhydrase, Longji Li

Mahurin Honors College Capstone Experience/Thesis Projects

The natural enzyme carbonic anhydrase has gained attention in recent years for its ability to catalyze the interconversion of aqueous carbon dioxide (CO₂) and bicarbonate. However, it lacks the efficiency to qualify practical usage on a large scale due to its inherent deficiency and fragile nature. On the other hand, its active center can be used as an ideal model for the design of novel catalytic materials targeting carbon dioxide capture and sequestration. This study focused on the synthesis of a zinc-based metal-organic framework (Zn-MOF-1) mimicking the carbonic anhydrase using the solvothermal method. Important properties such as catalytic …

Heavy Metals Found In Juul's Electronic Cigarettes, Joshua F. Gesselberty

Honors Theses

Electronic cigarettes better known as e-cigarettes have been consistently rising in popularity with new products entering the market daily. E-cigarettes function by vaporizing a liquid composed of propylene glycol, glycerin, benzoic acid, nicotine, and flavor additives with the use of a metallic heating element. This vapor produced is then inhaled by the user. The composition of this liquid is critical to discovering the possible health effects.

This study investigates the presence and concentrations of heavy metals in the e-liquid before and after vaping. An ICP-MS was used because of its ability to scan several metals rapidly and its high sensitivity. …

Peer-To-Peer Energy Trading For Networked Microgrids, Jonathan David Warner

Theses, Dissertations and Capstones

Considering the limitations of the existing centralized power infrastructure, research interests have been directed to decentralized smart power systems constructed as networks of interconnected microgrids. Therefore, it has become critical to develop secure and efficient energy trading mechanisms among networked microgrids for reliability and economic mutual benefits. Furthermore, integrating blockchain technologies into the energy sector has gained significant interest among researchers and industry professionals. Considering these trends, the work in this thesis focuses on developing Peer-to-Peer (P2P) energy trading models to facilitate transactions among microgrids in a multiagent network. Price negotiation mechanisms are proposed for both islanded and grid-connected microgrid …

Routing And Applications Of Vehicular Named Data Networking, Bassma G. Aldahlan

Theses and Dissertations--Computer Science

Vehicular Ad hoc NETwork (VANET) allows vehicles to exchange important informationamong themselves and has become a critical component for enabling smart transportation.In VANET, vehicles are more interested in content itself than from which vehicle the contentis originated. Named Data Networking (NDN) is an Internet architecture that concentrateson what the content is rather than where the content is located. We adopt NDN as theunderlying communication paradigm for VANET because it can better address a plethora ofproblems in VANET, such as frequent disconnections and fast mobility of vehicles. However,vehicular named data networking faces the problem of how to efficiently route interestpackets and …

Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu

College of Graduate Studies: Theses & Dissertations

In recent years, lightweight structures have become mature and adopted in various applications. The importance of quality assurance cannot be overemphasized hence extensive research has been conducted to assess the quality of lightweight structures. This study investigates a novel process that exploits motion magnification to investigate the damage characteristics of lightweight mission-critical parts. The goal is to assure the structural integrity of 3D printed structures and composite structures by determining the inherent defects present in the part by exploiting their vibration characteristics. The minuscule vibration of the structure was recorded with the aid of a high-speed digital camera, and the …

Determination Of Pollutant Load Reductions To Three Mile Creek As A Result Of The Implementation Of Storm Water Bio-Infiltration Basins On The Usa Campus, Jordan E. Blackmon

Honors Theses

Three Mile Creek has been identified as an impaired urban stream and is now a priority for cleanup for both the City of Mobile and the Alabama Department of Environmental Management. Methods to better manage storm water runoff on the USA campus have begun, with a goal to reduce sediment and nutrient inputs to Three Mile Creek. Both sediment and nutrient inputs to Three Mile Creek disrupt habitat and lower dissolved oxygen concentrations, which are detrimental to overall stream health. Low Impact Development strategies are an innovative way to use nature-like, green-infrastructures to minimize storm water runoff quantity and improve …

Amplification And Filtering Stage For An In-Home Wireless Polysomnograph, Seth Young

Honors Theses

Obstructive sleep apnea is a sleep disorder that tends to be easily treatable but, for most sufferers, is undiagnosed. To lower the economic barriers to screening the design of a portion of a polysomnograph, or obstructive sleep apnea testing tool, is considered. A filtering and amplification stage is theorized, simulated, and constructed for testing. The stage, consisting of three cascaded 1st order Butterworth low pass filters and amplifiers, did not achieve the target signal to noise ratio for a sinusoidal waveform of amplitude 200µv, but showed promising signal to noise ratios for waveforms with amplitudes as low as 600µv. The …

Comparative Analysis Of Computationally Accelerated Ngs Alignment, Ada Chaeli Van Der Zijp-Tan

Honors Theses

The Smith-Waterman algorithm is the basis of most current sequence alignment technology, which can be used to identify similarities between sequences for cancer detection and treatment because it provides researchers with potential targets for early diagnosis and personalized treatment. The growing number of DNA and RNA sequences available to analyze necessitates faster alignment processes than are possible with current iterations of the Smith-Waterman (S-W) algorithm. This project aimed to identify the most effective and efficient methods for accelerating the S-W algorithm by investigating recent advances in sequence alignment. Out of a total of 22 articles considered in this project, 17 …

Ogt Glycosylation Of Histones In T Cells May Participate In Systemic Lupus Erythematosus, Jared Luke Ridgeway

Honors Theses

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease that primarily affects women. The etiology is not known yet, but genetics and environmental factors trigger the disease. These epigenetic changes modify gene expression and contribute to the development of the disease. It is known that T cells from patients with lupus overexpress genes that may contribute to the onset and progression of the disease. Dr. Gorelik has shown that OGT (O-linked N-acetyl-Glucosamine Transferase), which is an X-linked gene, is overexpressed in women with SLE. OGT adds b-N-acetylglucosamine (O-GlcNAc) to serine and threonine residues of proteins. …

On The Mechanical Properties Of Al/Cu-Grid/Al Intermetallic Composite, Hamza Essoussi, Said Ettaqi

Journal of Metals, Materials and Minerals

The present paper deals with the experimental investigation of new process combining static compression with high temperature as a simple way to prepare new Al/Cu-grid/Al metallic composite (MC) that consists of Aluminum matrix and Copper grid acting as ductile reinforcement stacked between the Al sheets. At the stage of composite fabrication, two different thermal cycles were tested to highlight the effect of processing temperature on the layers’ adherence and the mechanical properties of the prepared composites. Consequently, the microstructural and mechanical results revealed that the compression at 630℃ for 30 min, then furnace cooled to 450℃ followed by air cooling …

Thermal Behavior Of Solid Acids In The Rb3h(So4)2-Rbhso4 System Under Ambient Atmosphere, Chatr Panithipongwut Kowalski, Permpoon Chaijaroen, Farook Kaewniyom

Journal of Metals, Materials and Minerals

The thermal behavior of solid acids in the Rb3H(SO4)2-RbHSO4 system under ambient atmosphere has been studied in comparison to the previously reported high-temperature behavior of the same system under humidified atmosphere. The findings showed that, under this level of humidity, the transition of RbHSO4, the transition of Rb5H3(SO4)4, and the disproportionation of Rb3H(SO4)2, occurred at the same temperatures as those under humidified atmosphere. However, the results from differential scanning calorimetry did not reveal the reaction temperature between Rb3H(SO4)2 and RbHSO4 due to the slow process. The dehydration temperatures of Rb5H3(SO4)4 were surprisingly similar between the systems under low and high …

Graphene Enhanced Linear Low-Density Polyethylene Nanocomposites By Premixing And Melt Compounding, Wan Nazri Wan Busu, Ruey Shan Chen, Muhammad Jefri Mohd Yusof, Sahrim Ahmad

Journal of Metals, Materials and Minerals

In this study, linear low-density polyethylene/graphene nanoplatelets (LLDPE/GNPs) nanocomposites were prepared from conventional melt-mixing method and our new approach; two-step premix mixing technique. Indirect mixing technique (IDT) was employed to fabricate a premix of LLDPE/ GNPs in the ratio of 80:20 wt%. The effects of GNPs loadings and the processing method of nanocomposites on the mechanical strength, decomposition temperature, crystallinity, electrical impedance and morphology were investigated. Irrespective of processing methods, the prepared nanocomposites exhibited crystalline structure due to the presence of GNPs whilst the degradation temperature was recorded to be increased with GNPs loadings that signified improved thermal stability. The …

Preparation Of Transparent Alumina Thin Films Deposited By Rf Magnetron Sputtering, Busarin Noikaew Noikaew, Laksana Wangmooklang, Saisamorn Niyomsoan, Siriporn Larpkiattaworn

Journal of Metals, Materials and Minerals

Alumina (Al2O3) thin films were prepared by RF magnetron sputtering technique using Al2O3 ceramic target. Effects of sputtering powers and oxygen gas mixtures were investigated and the optimized coating condition was applied on semi-precious gemstones. RF sputtering powers were varied to optimize the transparency of the films. Besides, the oxygen gas mixtures were also studied at the optimized sputtering power with a constant sputtering pressure. Optical and physical properties of the thin films were investigated using UV-Vis Spectrophotometer, FESEM, XRF, GIXRD, XRR including a microscratch tester. The Al2O3 films were highly transparent in the visible region in form of an …

Extraction Of Cellulose Nanofibers From Empty Palm Fruit Bunches Via Mechanical Defibrillation, Zi-Qian Tan, Takaomi Kobayashi, Duangdao Aht-Ong

Journal of Metals, Materials and Minerals

In recent years, there has been an increasing interest in finding alternative material to replace fossil-oil based product due to the environmental concern. Lignocellulosic biomass has emerged as the promising candidate due to its low-cost and sustainability. The objective of this work was to prepare cellulose nanofibers (CNFs) from empty palm fruit bunches (EPFB), which are the waste originating from palm oil industry. Cellulose fibers were first extracted from EPFB by chemical treatment, followed by mechanical disintegration using high-pressure homogenization. Fiber concentration and defibrillation time during mechanical treatment were studied to investigate their effects on the properties of produced nanofibers. …

The Effect Of Phosphogypsum On Stabilizing Clay Soil And Improving Its Properties For Use As Foundation Soil, Mai Yahya Maaitah, Mus'ab Ziad Banat

Journal of Metals, Materials and Minerals

Expansive soil covers large areas in a variety of regions in Jordan which is insufficient to meet the engineering specifications in construction. Phosphogypsum is considered to be the main by-product material which comes from phosphate rock deposits that is available in Jordan. The main purpose of this research is to study the effects of stabilization by phosphogypsum on expansive soil properties. Three Jordanian regions were chosen to represent the expansive soils, Irbid, Madaba, and Abu-Nusire city. Soils were mixed with phosphogypsum at different percentages by dry weight of soil. Some of the representative laboratory tests for swell properties were conducted: …

The Effect Of Artificial Defects On The Fatigue Characteristics Of Aisi 4340 Steel, Yakov B. Unigovski, Dmitry Fishman, Liat Fishman, Liron Shichman, Ofir Moshe, Roni Shneck, Emmanuel Gutman

Journal of Metals, Materials and Minerals

This study examined the fatigue life (Nf) and fatigue limit (FL) of AISI 4340 steel in relation to surface roughness, artificial defects and shot peening. Artificial surface defects on fatigue specimens were obtained by electrical discharge machining (EDM) or by pre-corrosion in 3.5% NaCl and perchloric acid solutions, followed by a fatigue test. The presence of artificial defects of various sizes, taken into account by the area  parameter, led to a significant decrease in fatigue characteristics, while shot peening contributed to their noticeable improvement. Defects resulting from electrochemical corrosion had a much greater negative effect on fatigue …

The Enhancement Of Ethanol Gas Sensors Response Based On Calcium And Zinc Co-Doped Lafeo3/Fe2o3 Thick Film Ceramics Utilizing Yarosite Minerals Extraction As Fe2o3 Precursor, Endi Suhendi, Zeany Luckyta Amanda, Muhamad Taufik Ulhakim, Andhy Setiawan, Dani Gustaman Syarif

Journal of Metals, Materials and Minerals

A gas sensor is a renewed interest of research which has been developed to make a device that can be detected the harmful gases and applied in the several fields of industries. In this paper, we report the modified of gas sensor based thick film ceramic LaFeO3/Fe2O3 by added calcium and zinc co-doping prepared by screen-printed technique. In this work, yarosite mineral was utilized as Fe2O3 precursor. It aims to take the advantages of abundance natural resources in Indonesia to save a cost in gas sensor fabrication. Then, x-ray diffraction (XRD), scanning electron microscopy (SEM) and electrical properties characterization were …

Wollastonite And Talc Reinforced Polypropylene Hybrid Composites: Mechanical, Morphological And Thermal Properties, Naruedee Putfak, Amnouy Larpkasemsuk

Journal of Metals, Materials and Minerals

This study focused on evaluating the mechanical, thermal, and morphological properties of polypropylene (PP) hybrid composites containing two different inorganic mineral fillers, namely wollastonite (WO) and talc. The composites were prepared by melt mixing process using a twin screw extruder and an injection molding machine. All composites contained a constant filler loading at 20 wt% with varying WO/talc weight ratios (20/0, 15/5, 10/10, 5/15, and 0/20). Melt flow index (MFI), mechanical properties (impact strength and tensile properties), heat distortion temperature (HDT) fractured surface morphology, and thermal behaviors of the resulting composites were investigated. The results revealed an enhancement in the …

Effect Of Nitrocarburizing And Argon Admixing On Low Carbon Steel For Component Facility In Radiometallurgical Installation, Erwan Hermawan, Suprapto Suprapto, Usman Sudjadi, Siti Shaleha, Maman Kartaman Ajiriyanto

Journal of Metals, Materials and Minerals

Steel is an important component in the industrialized world with rising growth in world consumption. Steel has wide applications due to its high strength, durability, and cost-effectiveness. This has applications in the nuclear power plant. In Indonesian nuclear industry, low carbon steel is used not only for the fabrication of reactor components but also for the radiometallurgical facilities. However, to avoid the risk of premature failure and enhance the longevity of the components in the service condition, surface modification for the improvement of hardness has been realized. Amongst several methods, surface hardening by following nitrocarburizing has been found to be …

Structural, Magnetic And Transport Properties Of Ca And Sr Doped Lanthanum Manganites, Sunita Keshri, Shailendra Rajput, Sonali Biswas, Leena Joshi, Wojciech Suski, Piotr Wiśniewski

Journal of Metals, Materials and Minerals

This article presents a comparative study for the effect of average A-site cation size on the structural, transport and magnetic properties of Lanthanum manganites. Three polycrystalline colossal magneto-resistive compounds were synthesized using standard solid state reaction method. The electrical resistivity data were analyzed employing standard two-phase model to understand the conduction mechanism. The resistance of polycrystalline ceramic depends on the intragrain resistance (intrinsic resistance) and the intergrain or grain-boundary resistance (extrinsic resistance). The substitution of Sr ions at La-site provides higher magnetic and metal-insulator transitions as compared to Ca ions. The combined substitution of Ca and Sr ions at La-site …