Engineering Commons^™

Deep Well Pump Seal, Peter M. Gordon, Matt C. Johnson, Dylan A. Smith

Mechanical Engineering

Lifewater International, a Christian non-profit, trains locals to repair water well hand pumps in various third world countries. It would be beneficial to retrofit difficult-to-repair hand pumps with a locally-made pump cylinder such as HydroMission's "SlapShot". The majority of the components in the "SlapShot" can be easily obtained in rural third world villages. However, the thick leather gaskets required to seal the water cylinder during the pumping operation are imported. These thick leather gaskets are expensive, and when they fail, this results in pumps being out of commission for extended periods of time. Lifewater has presented this problem to a …

Dyno-Mite Redesign, Brandon Joseph Miller, Daniel Robert Hoffman, Richard Demedici Young

Mechanical Engineering

The Cal Poly Mechanical Control Systems Laboratory currently employs an outdated device, known as the Motomatic, to teach students about various motor characteristics and control methods. These include open-loop vs. closed-loop control, speed vs. position control, and DC motor response curves. The current device does not function properly and produces unreliable data due to overwhelming non-linear effects such as stiction and shaft misalignment. Our team was tasked with designing a replacement device that retains many of the same educational goals as the original lab procedure, while also adding new educational goals pertaining to the device system dynamics. The new apparatus, …

Rogue Rotary - Modular Robotic Rotary Joint Design, Sean Wesley Murphy, Tyler David Riessen, Jacob Mark Triplett

Mechanical Engineering

This paper describes the design process from ideation to test validation for a singular robotic joint to be configured into a myriad of system level of robots.

Poly Spotlight Control, Ryan P. O'Neill, C. Oleg Frandle, Anthony T. Lombardi

Mechanical Engineering

When this project began, The Cambria Center for the Arts Theater used a manually-operated spotlight. The sound created by the fans, along with the sheer size of the spotlight, required that it be housed in an attic room above the theater and shined through a closed window. This trapped a lot of heat in the room and involved some risk with climbing into and out of the attic room. This project sought to remedy those issues by mounting a pair of newer LED spotlights inside the theater. Doing this required a method for remotely controlling and actuating the angular position …

An Analysis Of The Size And Impact Of Digital Footprints, Whitney Nielsen Maxwell

Theses and Dissertations

Personal information available online is known as a digital footprint. While many have a digital footprint, few if any, know what it encapsulates or how to control it. Technology and personal information are becoming more intertwined as technology becomes more integrated with everyday activities. Personal information can be defined as details that apply to a person such as race or shopping habits. Shopping habits are considered personal information by many corporations who spend money to track, or even predict purchases of individuals, whereas more traditional forms of personal information are details like gender, birthdate, and home town. With a wide …

A Comparison Between Self-Cleaning Properties Via Rolling Droplets And Condensation On Superhyrophobic Surfaces, David Leland Miller

Theses and Dissertations

Superhydrophobic (SH) surfaces are super water repellent surfaces on which a droplet of water will bead up like a marble and roll off the surface with minimal tilting of the surface. This is caused by the combination of a hydrophobic coating and a rough surface structure. To achieve thermodynamic stability, surface tension of the water pulls the droplet into this shape to minimize the contact area between the droplet and the surface. This creates a high contact angle (CA) between the droplet and the surface and a low sliding angle (SA) of which the droplet begins to roll off the …

Project Management: Skills, Tools, And Knowledge Construction Professionals Consider Important For Keeping Projects On Schedule, Lyle Scott Davies

Theses and Dissertations

Project managers have a major role in the construction and completion of projects. Much of their work consists of reviewing, clarifying, and coordinating information required by the field management and subcontractors performing the work on the job site. The assistance they give with the transfer of information helps with successfully completing projects. For many people, the largest indicator that a project was successful is that construction activities were completed on schedule. While finishing on schedule may be the primary focus of those involved with construction activities, projects still struggle to finish on time. The purpose of this study is to …

Advancements In Radio Astronomical Array Processing: Digital Back End Development And Interferometric Array Interference Mitigation, Mitchell Costus Burnett

Theses and Dissertations

The Brigham Young University (BYU) Radio Astronomy Systems group, in collaboration with the National Radio Astronomy Observatory (NRAO), the Center for Astrophysics at West Virginia University (WVU), and the Green Bank Observatory (GBO) have developed, and commissioned, a broadband real-time digital back end processing system for a 38-element phased array feed (PAF) with 150 MHz of instantaneous bandwidth. This system is capable of producing coarse and fine channel correlations, and implements a real-time beamformer that forms 7 simultaneous dual-polarized beams. This thesis outlines the hardware and software development for the digital back end and presents on-telescope commissioning results. This system …

Investigating If Multidisciplinary Or Homogenous Teams Are More Innovative In A Higher Education Setting, Blake Howard Hoover

Theses and Dissertations

This study is derived from the claim that multidisciplinary groups are more innovative than homogeneous groups; a claim that has flooded the business industry and has become criteria for accreditation in higher education. However, the impact of disciplinary diversity in work groups is a growing area of research; therefore, it is yet to be thoroughly understood. The purpose of this study is to answer the question: are multidisciplinary teams more innovative than homogenous teams. To accomplish this university students from differing majors were sorted into multidisciplinary and homogeneous groups while participating in a two-day innovation course. The course taught the …

Analysis Of Safety Impacts Of Access Management Alternatives Using The Surrogate Safety Assessment Model, Kyung Min Kim

Theses and Dissertations

In a traditional safety impact analysis, it is necessary to have crash data on existing roadway conditions in the field and a few years must pass before accumulating reliable crash data. This is a time-consuming approach and there remains uncertainty in the crash data due to the random nature of crash occurrences. The Surrogate Safety Assessment Model (SSAM) was developed for resolving these issues. With SSAM, a conflict analysis is performed in a simulated environment. A planned improvement alternative under study is modeled and no physical installation of the alternative is needed. Hence, the method using a simulation software along …

Tribopairs In Wellbore Drilling: A Study Of Pcd Tilting Pad Bearings In An Electric Submersible Pump, Cameron B. Ellis

Theses and Dissertations

A polycrystalline diamond was tested as a bearing material for a tilting pad thrust bearing to be used in an electric submersible pump, which elevates process fluids from the bottom of well bores. The goal of this study was to compare the PCD to a current best of technology, which is stainless steel with an engineering polymer.This study found that PCD can handle larger loads than current technology but is limited in size due to diamond sintering and manufacturing constraints. The maximum size is Ø75mm.

An Investigation Of Elementary Teachers<'> Self-Efficacy For And Beliefs About The Importance Of Engineering Education, Khristen Lee Massic

Theses and Dissertations

In order for the United States to regain its global standing in science and engineering, educational and governmental organizations have started to re-emphasize science, technology, engineering, and math content in k-12 classrooms.While some preliminary research has been conducted on student and teacher perceptions related to engineering, there has been little research conducted related to teachers beliefs about the importance of engineering content in their classrooms and relatively few studies have investigated elementary teachers teaching engineering self-efficacy. Current studies have investigated the impact of professional development on teachers teaching engineering self-efficacy but these studies were conducted with limited sample sizes, for …

Coorstek- Spine Discectomy, Rhett Prestwich, Logan Bolingbroke, Ryan Thomsen, Aaron Blanchard, Kayla Park

Undergraduate Honors Capstone Projects

The objective is to design improved instrumentation for performing a spine discectomy. In particular, the instrument should remove the nucleus pulposus without damaging the annulus in order to prepare the spine disc for the insertion of an artificial spacer. As more nucleus pulposus is removed from the disc, the spine will fuse more quickly and completely after the artificial spacer is inserted. The current process involves removing the nucleus pulposus piece by piece with pituitary rongeurs. This process is slow and often incomplete.

Determination Of Safe Ballasts For Anchoring Event Tents By Finite Element Analysis, Sandeep Manoharan

All Theses

Event tents are large structures made of fabric covers attached to a structural frame and poles. Every year, many temporarily installed tents are subjected to large wind conditions that lead to sliding or lift of the frame due to improper anchoring to the ground. When ballasted, as opposed to anchored using stakes that penetrate the ground, non-certified tents are generally installed without proper analysis of sufficient ballast weights, which results into tent movements and lack of safety. The objective of this thesis is to determine load factors for non-certified tents affected by high wind loads. The load requirements (load factors) …

Me-Em Enewsbrief, July-December 2017, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical and Aerospace Engineering eNewsBrief

No abstract provided.

A Silicon Carbide Power Management Solution For High Temperature Applications, Robert Murphree

Graduate Theses and Dissertations

The increasing demand for discrete power devices capable of operating in high temperature and high voltage applications has spurred on the research of semiconductor materials with the potential of breaking through the limitations of traditional silicon. Gallium nitride (GaN) and silicon carbide (SiC), both of which are wide bandgap materials, have garnered the attention of researchers and gradually gained market share. Although these wide bandgap power devices enable more ambitious commercial applications compared to their silicon-based counterparts, reaching their potential is contingent upon developing integrated circuits (ICs) capable of operating in similar environments.

The foundation of any electrical system is …

Power Interface Design And System Stability Analysis For 400 V Dc-Powered Data Centers, Yuzhi Zhang

Graduate Theses and Dissertations

The demands of high performance cloud computation and internet services have increased in recent decades. These demands have driven the expansion of existing data centers and the construction of new data centers. The high costs of data center downtime are pushing designers to provide high reliability power supplies. Thus, there are significant research questions and challenges to design efficient and environmentally friendly data centers with address increasing energy prices and distributed energy developments.

This dissertation work aims to study and investigate the suitable technologies of power interface and system level configuration for high efficiency and reliable data centers.

A 400 …

Energy-Aware Sparse Sensing Of Spatial-Temporally Correlated Random Fields, Zuoen Wang

Graduate Theses and Dissertations

This dissertation focuses on the development of theories and practices of energy aware sparse sensing schemes of random fields that are correlated in the space and/or time domains. The objective of sparse sensing is to reduce the number of sensing samples in the space and/or time domains, thus reduce the energy consumption and complexity of the sensing system. Both centralized and decentralized sensing schemes are considered in this dissertation.

Firstly we study the problem of energy efficient Level set estimation (LSE) of random fields correlated in time and/or space under a total power constraint. We consider uniform sampling schemes of …

Peptoid-Modified Bicelles As Surrogate Cell Membranes For Membrane Protein Sensors And Analytics, Helya Najafi

Graduate Theses and Dissertations

Membrane-affiliated interactions are significant in understanding cell function, detecting biomarkers to diagnose disease, and in testing the efficiency of new therapeutic targets. Model membrane systems have been developed to study membrane proteins, allowing for stable protein structure and maintaining native activity. Bicelles, disc-shaped lipid bilayers created by combining long- and short-chain phospholipids, are the model membrane system of focus in this study. Bicelles are accessible from both sides and have a wide size range, which make them attractive for studying membrane proteins without affecting function. In this work, bicelles were functionalized with two peptoids to alter the edge and face …

Energy Shaping Control For Stabilization Of Interconnected Voltage Source Converters In Weakly-Connected Ac Microgrid Systems, Nadia Lenora Carmita Smith

Graduate Theses and Dissertations

With the ubiquitous installations of renewable energy resources such as solar and wind, for decentralized power applications across the United States, microgrids are being viewed as an avenue for achieving this goal. Various independent system operators and regional transmission operators such as Southwest Power Pool (SPP), Midcontinent System Operator (MISO), PJM Interconnection and Electric Reliability Council of Texas (ERCOT) manage the transmission and generation systems that host the distributed energy resources (DERs). Voltage source converters typically interconnect the DERs to the utility system and used in High voltage dc (HVDC) systems for transmitting power throughout the United States. A microgrid …

Modeling And Simulation Of Iii-Nitride-Based Solar Cells Using Nextnano®, Malak Refaei

Graduate Theses and Dissertations

Nextnano³ software is a well-known package for simulating semiconductor band-structures at the nanoscale and predicting the general electronic structure. In this work, it is further demonstrated as a viable tool for the simulation of III-nitride solar cells. In order to prove this feasibility, the generally accepted solar cell simulation package, PC1D, was chosen for comparison. To critique the results from both PC1D and Nextnano3, the fundamental drift-diffusion equations were used to calculate the performance of a simple p-n homojunction solar cell device analytically. Silicon was picked as the material for this comparison between the outputs of the two simulators as …

Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh

Graduate Theses and Dissertations

This research proposes novel solution techniques to optimize two real-world problems in the area of scheduling and transportation. We first consider a model for optimizing the operations of dredges. In this problem, scheduling and assignment decisions are integrated across a finite planning horizon. Additional constraints and problem elements explicitly considered include, but are not limited, to environmental work window restrictions, budget limitations, dredge operation rates and schedule-dependent dredge availability. Our approach makes use of Constraint Programming (CP) to obtain quality and robust solutions within an amount of time small enough to be useful to practitioners. The expanded feature set of …

Law Enforcement Resource Optimization With Response Time Guarantees, Jonathan Chase, Jiali Du, Na Fu, Truc Viet Le, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In a security-conscious world, and with the rapid increase in the global urbanized population, there is a growing challenge for law enforcement agencies to efficiently respond to emergency calls. We consider the problem of spatially and temporally optimizing the allocation of law enforcement resources such that the quality of service (QoS) in terms of emergency response time can be guaranteed. To solve this problem, we provide a spatio-temporal MILP optimization model, which we learn from a real-world dataset of incidents and dispatching records, and solve by existing solvers. One key feature of our proposed model is the introduction of risk …

Who Are Your Users? Comparing Media Professionals' Preconception Of Users To Data-Driven Personas, Lene Nielsen, Soon-Gyu Jung, Jisun An, Joni Salminen, Haewoon Kwak, Bernard J. Jansen

Research Collection School Of Computing and Information Systems

One of the reasons for using personas is to align user understandings across project teams and sites. As part of a larger persona study, at Al Jazeera English (AJE), we conducted 16 qualitative interviews with media producers, the end users of persona descriptions. We asked the participants about their understanding of a typical AJE media consumer, and the variety of answers shows that the understandings are not aligned and are built on a mix of own experiences, own self, assumptions, and data given by the company. The answers are sometimes aligned with the data-driven personas and sometimes not. The end …

The Psychological Health Of Airline Pilots: A Flight Deck Crew’S Perceptions And Willingness To Fly, Jason Charles Herkimer

Theses and Dissertations

Pilots have an image of bravado and charisma which includes that of a hardened, unemotional professional. What happens when the inevitable hardship occurs to a pilot? In the past, physical attributes were highly sought after in the recruitment of pilots. Eventually, pilots can and will suffer from the same psychological stressors as the general population. The purpose of this study is to determine the effect stigmatizing attitudes and psychological treatment of pilots have on a flight deck crew’s willingness to fly. The current study incorporated several different methodologies including a between subjects true experimental, an analysis of covariance (ANCOVA), an …

Mining Electrical Meter Data To Predict Principal Building Use, Performance Class, And Operations Strategy For Hundreds Of Non-Residential Buildings, Clayton Miller, Forrest Meggers

Research Collection College of Integrative Studies

This study focuses on the inference of characteristic data from a data set of 507 non-residential buildings. A two-step framework is presented that extracts statistical, model-based, and pattern-based behavior. The goal of the framework is to reduce the expert intervention needed to utilize measured raw data in order to infer information such as building use type, performance class, and operational behavior. The first step is temporal feature extraction, which utilizes a library of data mining techniques to filter various phenomenon from the raw data. This step transforms quantitative raw data into qualitative categories that are presented in heat map visualizations …

Policy Gradient With Value Function Approximation For Collective Multiagent Planning, Duc Thien Nguyen, Akshat Kumar, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Decentralized (PO)MDPs provide an expressive framework for sequential decision making in a multiagent system. Given their computational complexity, recent research has focused on tractable yet practical subclasses of Dec-POMDPs. We address such a subclass called CDec-POMDP where the collective behavior of a population of agents affects the joint-reward and environment dynamics. Our main contribution is an actor-critic (AC) reinforcement learning method for optimizing CDec-POMDP policies. Vanilla AC has slow convergence for larger problems. To address this, we show how a particular decomposition of the approximate action-value function over agents leads to effective updates, and also derive a new way to …

Efficient Gate System Operations For A Multipurpose Port Using Simulation Optimization, Ketki Kulkarni, Trong Khiem Tran, Hai Wang, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Port capacity is determined by three major infrastructural resources namely, berths, yards and gates. Theadvertised capacity is constrained by the least of the capacities of the three resources. While a lot ofattention has been paid to optimizing berth and yard capacities, not much attention has been given toanalyzing the gate capacity. The gates are a key node between the land-side and sea-side operations in anocean-to-cities value chain. The gate system under consideration, located at an important port in an Asiancity, is a multi-class parallel queuing system with non-homogeneous Poisson arrivals. It is hard to obtaina closed form analytic approach for …

Nitrogen Doped Carbon Nanofibers Derived From Water-Soluble Precursors, Lee Cremar, Ben Jones, Nicole Martinez, Gustavo Mejia, Hilario Cortez, Edgar Muñoz, Rocío Nava, Karen Lozano

Mechanical Engineering Faculty Publications

Nitrogen doped carbon fibers were synthesized from polyvinyl alcohol (PVA), a water soluble precursor. The PVA fine fibers were first developed by centrifugally spinning an aqueous based solution using Forcespinning® technology. The precursor fibers were then exposed to sulfuric acid vapors to partially carbonize and stabilize the fibers for further heat treatment. For nitrogen doping, the fibers were exposed to two different heat treatment routes. One was under a nitrogen atmosphere at 850°C followed by exposure to ammonia gas at 500°C. The second route consisted of heating the treated fibers in pure ammonia gas only, up to 850°C. Both heating …

Micro-Cantilever Based Fiber Optic Hydrophone, Jie Liu

All Dissertations

Endoscopic photoacoustic imaging probe is becoming increasingly important for many clinical photoacoustic imaging applications in which the target tissue can only be accessed by introducing an endoscopic probe percutaneously or through a natural orifice. Miniature fiber optic hydrophone (FOH) has become an attractive choice for endoscopic photoacoustic imaging application. Fiber optic hydrophone has many proven advantages, including small size, light weight, immunity to electromagnetic interference, low cost for single-use application and capability of integration of excitation light source and acoustic wave receiver.

This dissertation demonstrates an open cavity, micro-cantilever based fiber optic Fabry-Perot interferometer (FPI) hydrophone. A fused silica micro-cantilever …