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2019

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Full-Text Articles in Engineering

Projekti Ideor Për Rehabilitimin E Rrugës Nacionale N25.3, Segmenti Qendra E Gjilanit, Armend Sertolli May 2019

Projekti Ideor Për Rehabilitimin E Rrugës Nacionale N25.3, Segmenti Qendra E Gjilanit, Armend Sertolli

Theses and Dissertations

Ky punim kryesisht përbëhet nga mbledhja dhe shqyrtimi i literaturave të ndryshme që ndërlidhen me punimet tokësore për ndërtimin e infrastrukturës rrugore. Në shtjellimin e kësaj teme të punimit të diplomës jam shërbyer me metodën e analizës kërkimore dhe me metodën e hulumtimit, softverve të ndryshëm si dhe dalja në terren dhe inspektimin nga afër ku do të realizohet projekti ideor për rehabilitimin e rrugës nacionale N25.3, segmenti qendra e Gjilanit. Në bazë të të dhënave që kemi grumbulluar në terren kemi formuar një ide rreth këtij projekti dhe kemi ardhur në përfundim se gjatë këtij projekti duhet ti kemi …


Projekti Ideor Për Rrugën ‘’2 Korriku’’ (Lagjja Ramuk - Kashan) – Hani I Elezit, Arianit Murseli May 2019

Projekti Ideor Për Rrugën ‘’2 Korriku’’ (Lagjja Ramuk - Kashan) – Hani I Elezit, Arianit Murseli

Theses and Dissertations

Nga paraqitja e idesë për nevojën e ndërtimit të rrugës"2 KORRIKU" (Lagjja Ramuk- Kashan) e deri tek ndërtimi i saj janë bërë studime të shumta të qarkullimit, rëndësisë ekonomike dhe shoqërore, me qëllim që ndërtimi i rrugës t’i përgjigjet llojit të destinimit. Studimet që janë bërëjanë bazuar në disa variante dhe nga këto është caktuar rëndësia dhe niveli i rrugës së re në kuadër të rrjetit ekzistues rrugor.Ndërtimi i kësaj rruge ka për qëllim lehtësimin e qarkullimit të qytetareve për nevojat e tyre.

Kjo rrugë ka edhe një rendësi të veçantë sepse në rast të bllokimit të rrugës magjistrale "IMER …


Implications Of Combination Of Operating Systems And Programming Languages On Parallel Programming Efficiency, Isaac Cerda May 2019

Implications Of Combination Of Operating Systems And Programming Languages On Parallel Programming Efficiency, Isaac Cerda

Honor’s College Freeman Research Journal

There are a number of programming languages and operating systems, and the appropriate selection of the two depends on the type of application. The effective application of parallel programming depends on a number of factors such as hardware and software, the application type, and the cost. At the micro level, understanding the concepts of threading, processors, and memory are also critical factors in deciding the type of parallel programming to use. The purpose of this paper is to discuss the impact of different combinations of operating systems and programming languages on the efficiency of parallel programming.


Duocel Metal Foam Display Cases, Kate Goldsworthy, Katherina Prodanov, Benjamin Swanson, Syed Hasan May 2019

Duocel Metal Foam Display Cases, Kate Goldsworthy, Katherina Prodanov, Benjamin Swanson, Syed Hasan

Mechanical Engineering

This Final Design Review (FDR) report outlines the senior design project that was conducted by a team of four mechanical engineering students at California Polytechnic State University-San Luis Obispo for ERG Materials and Aerospace Corporation. The goal of this project was to design displays that showcase the properties of ERG’s Duocel® foam at tradeshows and client meetings. To better understand the needs of our sponsor, the team researched Duocel®’s capabilities, related technologies, and relevant standards and regulations. With this information, we further defined the problem by creating a problem statement and a set of engineering specifications through a Quality Function …


Insulated Solar Electric Cooker With Phase Change Thermal Storage Medium, Justin Brett Unger, Nathan Robert Christler, Matthew Weeman, Marcus Edward Strutz May 2019

Insulated Solar Electric Cooker With Phase Change Thermal Storage Medium, Justin Brett Unger, Nathan Robert Christler, Matthew Weeman, Marcus Edward Strutz

Mechanical Engineering

This final design review document outlines the senior design project carried out by a team of four mechanical engineering students at the California Polytechnic State University – San Luis Obispo under the sponsorship of Dr. Peter Schwartz of the Cal Poly Physics department. The aim of this project was to improve upon the design of previously developed Insulated Solar Electric Cookers (ISECs) by adding a thermal storage system to allow for quicker cook times and the ability to cook food at non-peak solar hours. The team’s goal was to develop a working prototype utilizing a phase change medium as the …


Framed Human Powered Vehicle Frame, Keyanna Brielle Henderson, Brendon Howard Morey, Kyra Noelle Schmidt, Austin Patrick Henry May 2019

Framed Human Powered Vehicle Frame, Keyanna Brielle Henderson, Brendon Howard Morey, Kyra Noelle Schmidt, Austin Patrick Henry

Mechanical Engineering

The following is the Final Design Review (FDR) Report for Framed, a team tasked with designing and fabricating the frame of the 2018-2019 Cal Poly Human Powered Vehicle (HPV) Club bike. The bike is to be raced at the 2019 World Human Powered Speed Challenge in Battle Mountain, Nevada with the goal of breaking the American collegiate speed record. The purpose of the FDR Report is to introduce the project’s background and objectives, discuss the final design, and present the results of manufacturing and testing. Prior to beginning work on the design of the frame, the group conducted extensive research …


Vaccine Cooler For The Global Poor, Benjamin J. Larson, Cooper E. Gibson, Eilbron Younan, Cody R. Volk May 2019

Vaccine Cooler For The Global Poor, Benjamin J. Larson, Cooper E. Gibson, Eilbron Younan, Cody R. Volk

Mechanical Engineering

Cal Poly physics professors Peter Schwartz and Nathan Heston approached the Solar Freeze team with the problem that remote communities in Africa have limited access to modern-day medicine or vaccines. They suggested that we try and design a cooling device that can keep vaccines cold for multiple days at a time while the medicine is transported to remote villages. Currently, there are vaccine cooler products on the market, but most of them are very expensive or lack portability. Peter and Nate have tasked the Solar Freeze team to come up with a less expensive solution that is also portable and …


A Review Of Field Oil-Production Response Of Injection-Well Gel Treatments, Munqith Aldhaheri, Mingzhen Wei, Na Zhang, Baojun Bai May 2019

A Review Of Field Oil-Production Response Of Injection-Well Gel Treatments, Munqith Aldhaheri, Mingzhen Wei, Na Zhang, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

As life-span extenders, bulk gels have been widely applied to rejuvenate oil production from uneconomic producers in mature oil fields by improving the sweep efficiency of improved-oil-recovery (IOR)/enhanced-oil-recovery (EOR) floods. This paper presents a comprehensive review of the responses of injection-well gel treatments implemented between 1985 and 2014. The survey includes 61 field projects compiled from SPE papers and US Department of Energy reports. Seven parameters related to the oil-production response were evaluated according to the reservoir lithology, formation type, and recovery process, using univariate analysis and stacked histograms. The interquartile-range (IQR) method was used to detect the underperforming and …


Solar Tracking Using A Parallel Manipulator Mechanism To Achieve Two-Axis Position Tracking, Joseph Otto Hubach May 2019

Solar Tracking Using A Parallel Manipulator Mechanism To Achieve Two-Axis Position Tracking, Joseph Otto Hubach

Graduate Theses - Mechanical Engineering

A novel solar tracker is presented that uses a parallel manipulator for the tracking mechanism instead of a traditional serial manipulator. The motivation is to create a solar tracker that displays the advantages of two-axis tracking systems (e.g., increased exposure to incident radiation, and enabling the use of efficient concentrating solar cells) while addressing some of the disadvantages of current two-axis tracking systems (e.g., the difficulties associated with having actuators mounted to moving elements within the mechanism). The mobility of the proposed parallel manipulator is examined using Grübler’s Criterion to establish that the manipulator displays the required two degrees of …


Data Visualization Of Treatment Outcomes For Tuberculosis Patients, Joy Jenkins May 2019

Data Visualization Of Treatment Outcomes For Tuberculosis Patients, Joy Jenkins

Industrial Engineering Undergraduate Honors Theses

Tuberculosis is an infectious disease, and different treatments have been discovered over the years. However, patients may develop various drug resistance levels that affect the likelihood of becoming cured or dying. In this study, we sought to employ data visualization to explore the relationship between treatment trajectory, as indicated by smear and culture results in the follow-up tests and patient outcomes. A large sample of patients have been broken down by demographics including age, gender, and drug resistance status. Sankey diagrams were used to visualize the pathway progression of the patients over time split between two time periods- months 0-6 …


Enhanced Security System With Image Feature Identification, Musharrat Chowdhury May 2019

Enhanced Security System With Image Feature Identification, Musharrat Chowdhury

Publications and Research

Open source hardware and software will be used to acquire camera images and recognize and identify objects of interest in the image that would be used in new or existing personal security system. The mechanism of this system rotates either automatically or manually to track a face when a human is within view of the camera. The biometric security recognition system is a real world applications with complex effects of illumination and imaging conditions on live images.


A Comprehensive Behavioral Study On Lane Changing Manuevers, Saeed Reza Ramezanpour Nargesi May 2019

A Comprehensive Behavioral Study On Lane Changing Manuevers, Saeed Reza Ramezanpour Nargesi

Civil Engineering Dissertations - Archive

Since changing lanes might cause traffic congestion and car crashes, the investigation on different aspects of this behavior remains critical. In the past decades, most of lane changing behavior studies have continued to model this behavior mathematically. Lack of qualitative studies in traffic flow theory concepts, especially lane changing behavior is noticeable. This study tries to conduct a comprehensive view of lane changing behavior maneuvers with consideration and analysis the steps of the lane changing process. The author uses the mixed methodological approach to understand the factors which may cause drivers to change lane. After understanding the reasons that make …


Improving Multi-Reservoir Water Supply System Operation Using Ensemble Forecasting And Global Sensitivity Analysis, Reza Limon May 2019

Improving Multi-Reservoir Water Supply System Operation Using Ensemble Forecasting And Global Sensitivity Analysis, Reza Limon

Civil Engineering Dissertations - Archive

The objective of this research is to improve the cost-effectiveness, reliability and resilience of water supply system operation through the utilization of ensemble forecasting and optimization of the operating policies. For the effective operation of a multi-reservoir water supply system skillful inflow and outflow forecasts are required. To that end, this research first assesses the value of medium-range ensemble precipitation forecasts generated with the HEFS developed by the US NWS in increasing skill and lead time of ensemble inflow forecasts. The skill of reservoir outflow forecasts is then assessed using three different models with varying complexity. Also assessed in the …


Simultaneous Estimation Of Ocean Tides And Underwater Topography In The Weddell Sea, Edward D. Zaron May 2019

Simultaneous Estimation Of Ocean Tides And Underwater Topography In The Weddell Sea, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

A new model for theM2, S2, K1, and O1 tides in the Weddell Sea is developed by assimilating CryoSat-2 data into a barotropic tide model. A variational approach is used, which explicitly allows for errors in the water depth, that is, the bottom topography in open water and the water column thickness under floating ice shelves, so that an optimized estimate of the topography is obtained together with the tidal fields. In preparation for assimilation, the sensitivity of the tidal elevation to the interfacial drag at the sea floor and the ice-water interface (under the floating ice shelves) is investigated; …


Error-Floors Of The 802.3an Ldpc Code For Noise Assisted Decoding, Tasnuva Tarannum Tithi May 2019

Error-Floors Of The 802.3an Ldpc Code For Noise Assisted Decoding, Tasnuva Tarannum Tithi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In digital communication, information is sent as bits, which is corrupted by the noise present in wired/wireless medium known as the channel. The Low Density Parity Check (LDPC) codes are a family of error correction codes used in communication systems to detect and correct erroneous data at the receiver. Data is encoded with error correction coding at the transmitter and decoded at the receiver. The Noisy Gradient Descent BitFlip (NGDBF) decoding algorithm is a new algorithm with excellent decoding performance with relatively low implementation requirements. This dissertation aims to characterize the performance of the NGDBF algorithm. A simple improvement over …


Modeling And Experimental Determination Of Physical Properties Of Ge X Ga Y Se 1-X-Y Chalcogenide Glasses Ii: Optical And Thermal Properties, Jason Lonergan, Charmayne Lonergan, John Mccloy, Kathleen A. Richardson May 2019

Modeling And Experimental Determination Of Physical Properties Of Ge X Ga Y Se 1-X-Y Chalcogenide Glasses Ii: Optical And Thermal Properties, Jason Lonergan, Charmayne Lonergan, John Mccloy, Kathleen A. Richardson

Materials Science and Engineering Faculty Research & Creative Works

This study systematically analyzed the correlation between topological structure and chemical ordering on the optical and thermal properties of synthesized material in the glass forming region of the GexGaySe1-x-y ternary. A series of ten compositions from 5 to 30 mol% Ge and 5 to 15 mol% Ga were examined within the ternary, showing broadband infrared properties with transmission from 1 to 25 μm. Topological constraint theory applied to compositions examined exhibited sharp inflection at the average coordination number of = 2.67 defined as the chemical threshold where the glass network consists of tetrahedral Ge(Ga)Se2 …


Investigation Of Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Fe3o4 As Efficient Recyclable Magnetic Catalysts For Suzuki-Miyaura Cross-Coupling, Hany A. Elazab May 2019

Investigation Of Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Fe3o4 As Efficient Recyclable Magnetic Catalysts For Suzuki-Miyaura Cross-Coupling, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this research, a facile and reproducible approach was implemented for the synthesis of palladium nanoparticles supported on Fe3O4 with remarkable activity as an ideal catalyst for Suzuki-Miyaura cross-coupling. Magnetite supported Pd nanoparticles reveal high activity in Suzuki-Miyaura coupling reactions since they could be recycled up to seven times with the same high catalytic activity. This adopted method of catalyst synthesis has many advantages, including reproducibility and the reliability of the adopted synthetic method. The produced catalyst has unique magnetic properties to facilitate catalyst recovery from the reaction mixture by using a strong magnet as an external …


Fast Yield Estimation Of Multi-Band Patch Antennas By Pc-Kriging, Xiaosong Du, Leifur Leifsson, Slawomir Koziel May 2019

Fast Yield Estimation Of Multi-Band Patch Antennas By Pc-Kriging, Xiaosong Du, Leifur Leifsson, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The PC-Kriging metamodeling method is proposed for yield estimation of multi-band patch antennas. PC-Kriging is a combination of polynomial chaos expansion (PCE) and Kriging metamodeling, where PCE is used as a trend function for the Kriging interpolation metamodel. The method is demonstrated on the Ishigami analytical function and a dual-band patch antenna. The PC-Kriging is shown to reach the prescribed accuracy limit with significantly fewer training points than both PCE and Kriging. This translates into considerable computational savings of yield estimation over alternative metamodel-based procedures and direct EM-driven Monte Carlo simulation. The saving are obtained without compromising evaluation reliability.


Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu May 2019

Investigating Virus Clearance Via Ph Inactivation During Biomanufacturing, Wenbo Xu

Biomedical Engineering Undergraduate Honors Theses

In the processing of biopharmaceuticals, viral clearance and viral safety are important for the development of monoclonal antibodies. Murine xenotropic leukemia virus (XMuLV) is one of the retroviruses, recommended by Food and Drug Administration (FDA) as a model virus for viral clearance via inactivation from therapeutics derived from Chinese hamster ovary cells (CHO). A robust and effective method was investigated to clear or inactivate endogenous viruses by low pH inactivation. The effects of different conductivity and inactivated time on XMuLV clearance was determined. Acetate buffer was prepared with different conductivity, and 2% XMuLV was spiked into acetate buffer. XMuLV virus …


Effect Of Polymer Composition Of Injectable Hydrogels On Programmable Release Of Methylene Blue, Mary Brandecker May 2019

Effect Of Polymer Composition Of Injectable Hydrogels On Programmable Release Of Methylene Blue, Mary Brandecker

Biomedical Engineering Undergraduate Honors Theses

Temperature sensitive hydrogels have been used as injectable hydrogels because the polymer solutions can be liquid at room temperature and gel at body temperature. Injectable hydrogels have been used in biomedical applications to deliver drugs and other small molecules throughout the body. Methylene Blue was used as the drug in this study for its antioxidant and neuroprotective properties. PluronicⓇ F127 (PF127) is a copolymer consisting of repeating units of polyethylene oxide and polypropylene oxide in the form PEO-PPO-PEO. PF127 in solution is a temperature sensitive hydrogel that transitions to a gel at body temperature at specific polymer compositions. A standard …


Phenotypic Characterization Of Differentiation Of Human Mesenchymal Stem Cells To Smooth Muscle Cells, Jackson Hedrick May 2019

Phenotypic Characterization Of Differentiation Of Human Mesenchymal Stem Cells To Smooth Muscle Cells, Jackson Hedrick

Biomedical Engineering Undergraduate Honors Theses

Abdominal aortic aneurysms (AAAs) are expansions in the aortic wall with an increased tendency to rupture. These expansions are triggered by the breakdown of key aortic extracellular matrix (ECM) proteins—elastin and collagen. The degradation of aortic ECM proteins is the consequence of overexpressed matrix metalloproteases (MMPs)–MMP-2 and MMP-9. Adult vascular smooth muscle cells (SMCs) lack the ability to repair the elastic matrix assembly; thus, it is imperative to find a solution to both restore the imbalance of essential ECM proteins in the aorta and mitigate the effects of MMPs. Previous studies have revealed that bone marrow derived mesenchymal stem cells …


Crude Oil Price Prediction With Decision Tree Based Regression Approach, Engu Chen, Xin James He May 2019

Crude Oil Price Prediction With Decision Tree Based Regression Approach, Engu Chen, Xin James He

Journal of International Technology and Information Management

Crude oil is an essential commodity for industry and the prediction of its price is crucial for many business entities and government organizations. While there have been quite a few conventional statistical models to forecast oil prices, we find that there is not much research using decision tree models to predict crude oil prices. In this research, we develop decision tree models to forecast crude oil prices. In addition to historical crude oil price time series data, we also use some predictor variables that would potentially affect crude oil prices, including crude oil demand and supply, and monthly GDP and …


Ipv6 Diffusion Milestones: Assessing The Quantity And Quality Of Adoption, John Pickard, Mark Angolia, Dale Drummond May 2019

Ipv6 Diffusion Milestones: Assessing The Quantity And Quality Of Adoption, John Pickard, Mark Angolia, Dale Drummond

Journal of International Technology and Information Management

There are currently two versions of Internet Protocol (IP) in use today, IP version 4 (IPv4) and IP version 6 (IPv6). The original version, IPv4, was standardized in the early 1980s as part of the Defense Advanced Research Project Agency Internet program and became the official Internet protocol in 1983 (Kleinrock, 2010). IPv6 was standardized in 1995 as its successor to provide enhanced capabilities and address IPv4 technological limitations, most notable of which was the anticipated exhaustion of address space (Deering & Hinden, 1995). While the two protocols have some functional similarities, they are distinct and not backward compatible; IPv4-only …


The Role Of Emotional Expression In Accessing Social Networks: The Case Of Newcomers' Blogs, Michael J. Hine, Luciara Nardon, Daniel Gulanowski May 2019

The Role Of Emotional Expression In Accessing Social Networks: The Case Of Newcomers' Blogs, Michael J. Hine, Luciara Nardon, Daniel Gulanowski

Journal of International Technology and Information Management

Research has established the critical role of social networks in facilitating adjustment to foreign environments. Increasingly, social interactions are happening through computer mediated technology. This paper explores the role of emotional expression in newcomers’ blogs in developing and interacting with social networks in a new country. This research uses a dictionary-based text analytics approach to detect emotional expression in newcomers’ blog posts and their associated discussions. Blog posts with more emotional expression had more associated responses; discussions tended to be more positive than posts; and the relative amount of negative emotion in the discussions increases as posts become more negative. …


Ac Direct Drive Led Lighting Using Low Cost Analog Components, Miles Head May 2019

Ac Direct Drive Led Lighting Using Low Cost Analog Components, Miles Head

Master's Theses

This project explores the rapidly expanding area of AC direct drive for LED lighting. AC LED driving does not use typical DC-DC converter-based driving but uses semiconductor switches and a linear regulator to activate a number of LEDs proportional to the input voltage at any given time. This allows bulky, expensive magnetics to be eliminated from the system. The goal of this project was to design a scaled-down physical AC LED direct drive system to validate the conclusions of methods for improving efficiency from a previous investigation that found minimizing voltage across the linear regulating MOSFET led to higher efficiency …


Developing Material Specification And Application Criteria For Sealing Concrete Bridge Decks, Danny Wells, Sudhir Palle, Theodore Hopwood Ii May 2019

Developing Material Specification And Application Criteria For Sealing Concrete Bridge Decks, Danny Wells, Sudhir Palle, Theodore Hopwood Ii

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC) has more aggressively pursued preventive maintenance in recent years. Sealing concrete bridge decks is one preventive maintenance activity the Cabinet has actively pursued. KYTC’s Divisions of Maintenance and Structural Design requested assistance from researchers at the Kentucky Transportation Center (KTC) in developing a material specification and application criteria for sealing concrete bridge decks at an appropriate time in their life cycle.

To develop a material specification and application criteria for sealing concrete bridge decks, KTC researchers conducted the following work:

  1. Perform a national survey of departments of transportation (DOTs) for guidelines.
  2. Perform a literature search …


Design Optimization Of Electric Machines With 3d Fea And A New Hybrid Doe-De Numerical Algorithm, Narges Taran, Vandana Rallabandi, Dan M. Ionel, Greg Heins, Dean Patterson, Ping Zhou May 2019

Design Optimization Of Electric Machines With 3d Fea And A New Hybrid Doe-De Numerical Algorithm, Narges Taran, Vandana Rallabandi, Dan M. Ionel, Greg Heins, Dean Patterson, Ping Zhou

Power and Energy Institute of Kentucky Faculty Publications

This paper discusses the multi-objective optimization of axial flux permanent magnet (AFPM) machines with ferrite spoke-type magnets, utilizing 3D finite element models. Three-dimensional finite element analysis is computationally expensive, and furthermore, substantial computation time is expended by optimization algorithms in evaluating low performing designs whose performance is far from the optimum if the search space is not specified correctly. In this regard, this work proposes two new methods for identifying the search space. The search is limited to ranges of input geometric variables where high performing designs are likely to be found. The optimization algorithm utilized is based on surrogate …


Inductance Testing For Ipm Synchronous Machines According To The New Ieee Std 1812 And Typical Laboratory Practices, Vandana Rallabandi, Narges Taran, Dan M. Ionel, Ping Zhou May 2019

Inductance Testing For Ipm Synchronous Machines According To The New Ieee Std 1812 And Typical Laboratory Practices, Vandana Rallabandi, Narges Taran, Dan M. Ionel, Ping Zhou

Power and Energy Institute of Kentucky Faculty Publications

Equivalent circuit parameters serve as the basis for performance estimation and implementation of power electronic drives controls and therefore their accurate evaluation is very important. Specified in the newly approved IEEE Std 1812, a short-circuit test can be employed, in combination with an open-circuit measurement, in order to determine the back emf and the synchronous inductance. In the case of interior permanent magnet (IPM) machines, this approach can be used only to determine the d-axis inductance and additional and separate measurements are required for the q-axis inductance. In this respect, various methods, inclusive of dc step response tests, on-load tests, …


A Comparative Study Of Methods For Calculating Ac Winding Losses In Permanent Magnet Machines, Narges Taran, Vandana Rallabandi, Dan M. Ionel, Greg Heins, Dean Patterson May 2019

A Comparative Study Of Methods For Calculating Ac Winding Losses In Permanent Magnet Machines, Narges Taran, Vandana Rallabandi, Dan M. Ionel, Greg Heins, Dean Patterson

Power and Energy Institute of Kentucky Faculty Publications

In this study different methods of estimating the additional ac winding loss due to eddy currents at open-circuit are explored. A comparative study of 2D and 3D FEA, and hybrid numerical and analytical methods is performed in order to recommend feasible approaches to be employed. Axial flux permanent magnet (AFPM) machine case studies are included, namely a machine with open slots and a coreless configuration. These machine topologies are expected to present a substantial amount of ac winding loss, which would therefore need to be considered during optimal design. This study is one of the first ones to compare meticulous …


Design, Fabrication, And Characterization Of Multilayer Hyperbolic Metamaterials, James Dilts May 2019

Design, Fabrication, And Characterization Of Multilayer Hyperbolic Metamaterials, James Dilts

Graduate Theses - Physics and Optical Engineering

Hyperbolic metamaterials (HMMs) show extreme anisotropy, acting as metals and dielectrics along orthogonal directions. They are designed using the effective medium theory (EMT) and can be fabricated using standard semiconductor processing techniques. Current techniques used to characterize the optical behavior of HMMs have a high complexity or are unable to robustly determine the complex permittivity tensor. We describe the details of a procedure to obtain a very low mean-squared-error (MSE) for extraction of permittivity from hyperbolic metamaterials using spectroscopic ellipsometry. We have verified our procedure by fabricating three different samples of various materials and fill factors designed to have a …