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Full-Text Articles in Engineering

Additive Manufacturing And Performance Of Architectured Cement-Based Materials, Mohamadreza Moini, Jan Olek, Jeffrey P. Youngblood, Bryan Magee, Pablo D. Zavattieri Jan 2018

Additive Manufacturing And Performance Of Architectured Cement-Based Materials, Mohamadreza Moini, Jan Olek, Jeffrey P. Youngblood, Bryan Magee, Pablo D. Zavattieri

Lyles School of Civil Engineering Faculty Publications

There is an increasing interest in hierarchical design and Additive Manufacturing (AM)of cement-based materials. However, the brittle behavior of these materials and the presence of interfaces from the additive manufacturing process represent the current major challenges. Our work focuses on harnessing the heterogeneous interfaces by employing clever designs from bio-inspired Bouligand architectured materials. In this paper, we aim to demonstrate some key mechanisms that can allow brittle hardened cement-based materials to gain flaw-tolerant properties. Mechanisms such as cracktwisting at the interfaces have been previously observed in naturally-occurring orsynthetic composite Bouligand architectures. In this paper, a heterogeneous interface with porous characteristics …


Understanding How First-Generation College Students’ Out-Of-School Experiences, Physics And Stem Identities Relate To Engineering Possible Selves And Certainty Of Career Path, Dina Verdín, Allison Godwin, Gerhard Sonnert, Phillip M. Sadler Jan 2018

Understanding How First-Generation College Students’ Out-Of-School Experiences, Physics And Stem Identities Relate To Engineering Possible Selves And Certainty Of Career Path, Dina Verdín, Allison Godwin, Gerhard Sonnert, Phillip M. Sadler

School of Engineering Education Graduate Student Series

This full, research category study examines how out-of-school experiences in Grades 9-12 predict first-generation college students’ engineering possible selves and certainty of career path. The data for this study came from a large-scale survey on outreach programs which was distributed in first- semester English courses to capture an array of responses from students interested in STEM and non-STEM careers. We used structural equation modeling to examine a set of hypotheses: 1) out-of-school experiences would be mediated by interest and recognition in physics and STEM and no direct effect will be found for out-of-school experiences on physics and STEM identities, 2) …


Igniting Self-Directed Learning And Higher Level Workforce Competencies In An Aviation Curriculum, Timothy D. Ropp Jan 2018

Igniting Self-Directed Learning And Higher Level Workforce Competencies In An Aviation Curriculum, Timothy D. Ropp

IMPACT Presentations

Discusses the underlying concepts and pedagogies informing an IMPACT redesign course in Aviation, focused on developing workplace competencies and students' self-directed learning.


Development And Impact Of Teacher Social Capital In An Engineering Education Teacher Professional Development Program, Wei Zakharov Jan 2018

Development And Impact Of Teacher Social Capital In An Engineering Education Teacher Professional Development Program, Wei Zakharov

Libraries Faculty and Staff Scholarship and Research

Teacher social capital is a set of social interaction assets such as collegiality and collaboration that enable teachers to work with each other in groups to improve teaching and learning. This results in instructional improvement and student success in school reform.

This study discusses how an engineering education teacher professional development program has developed an environment for long-term collegiality and collaboration among its teachers. Furthermore, the study presents an empirical evidence of the impact of teacher social capital on students’ engineering knowledge learning.

Ninety teachers and 621 students are examined in this program. The participants are from fifteen elementary schools …


Brain Motion, Deformation, And Potential Injury During Soccer Heading, Charles F. Babbs Dec 2017

Brain Motion, Deformation, And Potential Injury During Soccer Heading, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

This paper addresses the problem of what is happening physically inside the skull during head-ball contact. Mathematical models based upon Newton’s laws of motion and numerical methods are used to create animations of brain motion and deformation inside the skull.

Initially a 1 cm gap filled with cerebrospinal fluid (CSF) separates the brain from the rigid skull in adults and older children. Whole head acceleration induces a pulse of artificial gravity within the skull. Because brain density differs slightly from that of CSF, the brain accelerates and strikes the inner aspect of the skull, undergoing viscoelastic deformation, ranging from 1 …


Supporting Mechanistic Reasoning In Domain-Specific Contexts, Paul J. Weinberg Dec 2017

Supporting Mechanistic Reasoning In Domain-Specific Contexts, Paul J. Weinberg

Journal of Pre-College Engineering Education Research (J-PEER)

Mechanistic reasoning is an epistemic practice central within science, technology, engineering, and mathematics disciplines. Although there has been some work on mechanistic reasoning in the research literature and standards documents, much of this work targets domain-general characterizations of mechanistic reasoning; this study provides domain-specific illustrations of mechanistic reasoning. The data in this study comes from the Assessment of Mechanistic Reasoning Project (AMRP) (Weinberg, 2012), designed using item response theory modeling to diagnose individuals’ mechanistic reasoning about systems of levers. Such a characterization of mechanistic reasoning illuminates what is easy and difficult about this form of reasoning, within the subdomain of …


Comparing Laser Diffraction And Optical Microscopy For Characterizing Superabsorbent Polymer Particle Morphology, Size, And Swelling Capacity, Cole R. Davis, Stacey L. Kelly, Kendra Erk Nov 2017

Comparing Laser Diffraction And Optical Microscopy For Characterizing Superabsorbent Polymer Particle Morphology, Size, And Swelling Capacity, Cole R. Davis, Stacey L. Kelly, Kendra Erk

School of Materials Engineering Faculty Publications

In this study, we determined the accuracy and practicality of using optical microscopy (OM) and laser diffraction (LD) to characterize hydrogel particle morphology, size, and swelling capacity (Q). Inverse-suspension-polymerized polyacrylamide particles were used as a model system. OM and LD showed that the average particle diameter varied with the mixing speed during synthesis for the dry (10–120 lm) and hydrated (34–240 lm) particles. The LD volume and number mean diameters showed that a few large particles were responsible for the majority of the water absorption. Excess water present in the gravimetric swelling measurements led to larger Qs (8.2 6 0.37 …


Gender And Participation In An Engineering Problem-Based Learning Environment, Laura Hirshfield, Milo D. Koretsky Nov 2017

Gender And Participation In An Engineering Problem-Based Learning Environment, Laura Hirshfield, Milo D. Koretsky

Interdisciplinary Journal of Problem-Based Learning

The use of problem-based learning (PBL) is gaining attention in the engineering classroom as a way to help students synthesize foundational knowledge and to better prepare students for practice. In this work, we study the discourse interactions between 27 student teams and two instructors in an engineering PBL environment to analyze how participation is distributed among team members, paying particular attention to the differences between male and female students. There were no statistically significant differences between the amount that male and female students spoke; however, stereotypical gender roles and traditional gendered behavior did manifest in the discussion. Also, regardless of …


Indiana Local Roads - An Asset Management Guide For Cities, Towns And Counties, Applied Pavement Technology, Inc. Nov 2017

Indiana Local Roads - An Asset Management Guide For Cities, Towns And Counties, Applied Pavement Technology, Inc.

Indiana Local Technical Assistance Program (LTAP) Publications

This Guide is designed to serve as a resource to agencies adopting an asset management philosophy. It presents an asset management process that can be used by any local agency in Indiana. It also introduces common terminology and helpful hints to get you started. The Guide promotes a statewide approach to gather and analyze the information you need to develop an asset management plan. You can use this Guide to: learn more about what asset management is, identify the steps involved with implementing asset management, discover ways to use data to better communicate with elected officials, develop an effective asset …


Open Access, Open Access, How Does Your Catalog Grow? With Selection, Access, And Usage All In A Virtual Row!, David W. Schuster, Susan J. Martin Oct 2017

Open Access, Open Access, How Does Your Catalog Grow? With Selection, Access, And Usage All In A Virtual Row!, David W. Schuster, Susan J. Martin

Charleston Library Conference

Much of the open access (OA) focus and discussion has been on journals (think Glossa), but the open access monograph has come fully into its own. University and scholarly publishers are providing high-quality books, often in areas that rely on long-form scholarship. However, open access monographs presented a challenge. How do they fit into the traditional models of selection, acquisition, cataloging, and tracking usage?

In the spring of 2016, Texas Woman’s University Libraries created a simple workflow to make open access monographs accessible through the libraries’ discovery layer using Google Sheets to track the workflow and EZproxy to track usage.


Geopolitics Of Rare Earth Elements, Bert Chapman Oct 2017

Geopolitics Of Rare Earth Elements, Bert Chapman

Libraries Faculty and Staff Presentations

Rare earth elements (REE) contain unique chemical physical properties such as lanthamum, are found in small concentrations, need extensive precise properties to separate, and are critical components of modern technologies such as laser guidance systems, personal electronics such as IPhones, satellites, and military weapons systems as varied as Virginia-class fast attack submarines, DDG-51 Aegis destroyers, the F-35 Joint Strike Fighter, and precision guided munitions. The U.S. has some rare earth resources, but is heavily dependent on access to them from countries as varied as Afghanistan, Bolivia, and China. Losing access to these resources would have significant adverse economic, military, and …


Safety Climate Of Ab-Initio Flying Training Organizations: The Case Of An Australian Tertiary (Collegiate) Aviation Program, Yi Gao, Natalia Rajendran Oct 2017

Safety Climate Of Ab-Initio Flying Training Organizations: The Case Of An Australian Tertiary (Collegiate) Aviation Program, Yi Gao, Natalia Rajendran

Journal of Aviation Technology and Engineering

A healthy safety culture is essential to the safe operation of any aviation organization, including flight schools. This study aimed to assess the safety climate of an Australian tertiary (collegiate) aviation program using a self-constructed instrument. Factor analysis of the instrument identified four safety themes, which are Safety Reporting Culture, Safety Reporting Procedure, Organizational Culture and Practice, and General Safety Knowledge. The responses of student pilots suggested that the overall safety climate of the subject flight training academy was healthy at the time of the survey. Further analyses found that perceptions of students of different year groups on Reporting Culture …


Profile Interview With Vincent Duffy, Apoorva Sulakhe Oct 2017

Profile Interview With Vincent Duffy, Apoorva Sulakhe

Purdue Journal of Service-Learning and International Engagement

Dr. Vincent Duffy is an associate professor in the Department of Industrial Engineering at Purdue University holding a joint appointment with Agricultural and Biological Engineering. Duffy focuses on human factors engineering and ergonomic design. His interest in teaching began early when he was a teaching assistant for IE 386 at Purdue University while pursuing his master’s degree. As an industrial engineering master’s non-thesis student, Duffy realized he had a natural inclination toward teaching. This motivation, along with the support and mentorship of Ferdinand Leimkuhler, the head of the department, turned him toward the fi eld of research. He rejoined Purdue …


Best Management Practices: A Community-Based Approach To Construction And Installation, Nathanael J. La Breche Oct 2017

Best Management Practices: A Community-Based Approach To Construction And Installation, Nathanael J. La Breche

Purdue Journal of Service-Learning and International Engagement

The Wabash River Enhancement Corporation (WREC) is a nonprofit organization dedicated to improving both the health of the Wabash River and the surrounding terrestrial areas. In an effort to improve water quality, their urban cost-share program focuses on supporting green projects within a critical region surrounding the Great Bend of the Wabash River. In this essay, a Purdue student describes his experience as leader of a six-member group who worked with WREC to locate a suitable site within this critical area and implement a green project. They selected the Lighthouse Baptist Church, located in Lafayette, Indiana, since it was experiencing …


Constructing Slow Sand Filters: Engineering Students’ Experiences In San José De Playón, Bolívar, Colombia, Sol Park, Sanyukta Gokhale, Kaylyn Colinco Oct 2017

Constructing Slow Sand Filters: Engineering Students’ Experiences In San José De Playón, Bolívar, Colombia, Sol Park, Sanyukta Gokhale, Kaylyn Colinco

Purdue Journal of Service-Learning and International Engagement

Sol Park, Sanyukta Gokhale, and Kaylyn Colinco were members of a Global Design Team (GDT) involved in providing innovative solutions to drinking water treatment in rural areas of developing countries. The immediate goal of the GDT in May 2016 was to deliver large slow sand filters (SSFs) to a rural school in Colombia. The experience placed the students in a small town 80 km (~50 miles) south of Cartagena, Colombia, called San José de Playón. The town pumps water from the Arroyo Reservoir, which is then consumed by the citizens and students at the local school (the only one in …


Answering Food Insecurity: Serving The Community With Food And Knowledge Using Technology, Courtney Simpson Oct 2017

Answering Food Insecurity: Serving The Community With Food And Knowledge Using Technology, Courtney Simpson

Purdue Journal of Service-Learning and International Engagement

The courses of Tech120, CGT110, and ENGT 180/181 and Red Gold at Purdue collaborated to design a robot that would plant and water a garden for a local community charter school. The students centered the project on the users’ needs for fresh food, nutrition education, and early exposure to STEM for children. The school, Anderson Preparatory Academy (APA), is comprised of many children who come from low-income families and are in the free or reduced lunch program. Inspired from “Farm Bot,” a similar system that allows for almost hands-free gardening, the “Boiler Bot” is designed to be scalable so children …


Water Supply In Developing Countries: Student Experiences In The Dominican Republic, Albert Alwang, Margaret Busse, Audrey Caprio, Marieke Fenton, Jason Hawes, Andrew Kanach, Autumn Mcelfresh-Sutton Oct 2017

Water Supply In Developing Countries: Student Experiences In The Dominican Republic, Albert Alwang, Margaret Busse, Audrey Caprio, Marieke Fenton, Jason Hawes, Andrew Kanach, Autumn Mcelfresh-Sutton

Purdue Journal of Service-Learning and International Engagement

In 2010, the United Nations established access to safe drinking water as a basic human right; however, many areas around the globe still lack access. The interdisciplinary service-learning course “Water Supply in Developing Countries” was established at Purdue in 2012 to address the complex issue of water insecurity around the world. Over the past five years, the course has produced teams involving students from nursing, engineering, agricultural economics, biology, and food science working together to develop sustainable, community-scale drinking water treatment systems. In partnership with Aqua Clara International, the student team in 2017 established a drinking water treatment system at …


Safety And Organization: An Epics Partnership With Habitat For Humanity, Trevor Drouillard, Logan Quaas, Colleen Kelch, Jeremiah Campbell, Anna Francis, Connor Moore, Jiayin Qi, Alyssa Trobl Oct 2017

Safety And Organization: An Epics Partnership With Habitat For Humanity, Trevor Drouillard, Logan Quaas, Colleen Kelch, Jeremiah Campbell, Anna Francis, Connor Moore, Jiayin Qi, Alyssa Trobl

Purdue Journal of Service-Learning and International Engagement

The student authors of this essay are a group of eight participating in the Engineering Projects in Community Service (EPICS) program on the Habitat for Humanity (HFH) team. In this article, they describe how they have improved the working conditions within the loft space of the local Habitat for Humanity office in Lafayette, Indiana. Their work is intended to permanently improve the safety conditions of the loft, as well as the organization of the equipment within the loft. The specific safety concerns addressed by the HFH team include horizontal steel trusses at head level and an unprotected access opening in …


Time Series Uav Image-Based Point Clouds For Landslide Progression Evaluation Applications, Abdulla Al-Rawabdeh, Adel Moussa, Marzieh Foroutan, Naser El-Sheimy, Ayman Habib Oct 2017

Time Series Uav Image-Based Point Clouds For Landslide Progression Evaluation Applications, Abdulla Al-Rawabdeh, Adel Moussa, Marzieh Foroutan, Naser El-Sheimy, Ayman Habib

Lyles School of Civil Engineering Faculty Publications

Landslides are major and constantly changing threats to urban landscapes and infrastructure. It is essential to detect and capture landslide changes regularly. Traditional methods for monitoring landslides are time-consuming, costly, dangerous, and the quality and quantity of the data is sometimes unable to meet the necessary requirements of geotechnical projects. This motivates the development of more automatic and efficient remote sensing approaches for landslide progression evaluation. Automatic change detection involving low-altitude unmanned aerial vehicle image-based point clouds, although proven, is relatively unexplored, and little research has been done in terms of accounting for volumetric changes. In this study, a methodology …


Prediction-Based Adaptive Robust Control For A Class Of Uncertain Time-Delay Systems, Jayaprakash Suraj Nandiganahalli, Cheolhyeon Kwon, Inseok Hwang Oct 2017

Prediction-Based Adaptive Robust Control For A Class Of Uncertain Time-Delay Systems, Jayaprakash Suraj Nandiganahalli, Cheolhyeon Kwon, Inseok Hwang

School of Aeronautics and Astronautics Faculty Publications

This paper presents an integrated control design approach for a class of dynamical systems that satisfy a certain matching condition subject to known input time-delay, unknown parameters, and time-varying disturbances, simultaneously. A novel nonlinear predictor adaptive robust control (PARC) is proposed to track a desired state trajectory. The controller uses predictor-based model compensation to attenuate the effect of input time-delay, gradient type projection with prediction-based learning mechanisms to reduce the parameter uncertainties, and prediction-based nonlinear robust feedback to attenuate the effect of model approximation errors and disturbances, simultaneously. The controller guarantees a prescribed transient performance (with global exponential convergence) and …


Latinx And Caucasian Elementary School Children’S Knowledge Of And Interest In Engineering Activities, Gamze Ozogul, Cindy Faith Miller, Martin Reisslein Oct 2017

Latinx And Caucasian Elementary School Children’S Knowledge Of And Interest In Engineering Activities, Gamze Ozogul, Cindy Faith Miller, Martin Reisslein

Journal of Pre-College Engineering Education Research (J-PEER)

Ethnic minorities, such as Latinx people of Hispanic or Latino origin, and women earn fewer engineering degrees than Caucasians and men. With shifting population dynamics and high demands for a technically qualified workforce, it is important to achieve broad participation in the engineering workforce by all ethnicities and both genders. Previous research has examined the knowledge of and interest in engineering among students in grades five and higher. In contrast, the present study examined elementary school students in grades K–5. The study found that older students in grades 4 and 5 had both greater knowledge of engineering occupational activities and …


Vfr-Into-Imc Accident Trends: Perceptions Of Deficiencies In Training, Wesley L. Major, Thomas Carney, Julius Keller, Allen Xie, Matt Price, John Duncan, Lori Brown, Geoffrey R. Whitehurst, William G. Rantz, Dominic Nicolai, Beth M. Beaudin-Seiler Oct 2017

Vfr-Into-Imc Accident Trends: Perceptions Of Deficiencies In Training, Wesley L. Major, Thomas Carney, Julius Keller, Allen Xie, Matt Price, John Duncan, Lori Brown, Geoffrey R. Whitehurst, William G. Rantz, Dominic Nicolai, Beth M. Beaudin-Seiler

Journal of Aviation Technology and Engineering

Pilots who operate under visual flight rules (VFR) and in visual meteorological conditions, who then continue flight into instrument meteorological conditions (IMC), remain as one of the leading causes of fatal aircraft accidents in general aviation. This paper examines past and current research initiatives, in seeking to identify causal factors and gaps in training that lead to VFR-into-IMC aircraft accidents, using a mixed methods approach. The Aircraft Owners and Pilots Association Air Safety Institute database and the National Transportation Safety Board database search engines were used to identify accident reports associated with VFR flight into IMC/deteriorating weather conditions for a …


Datumate, Purdue Ect Team Oct 2017

Datumate, Purdue Ect Team

ECT Fact Sheets

Datumate is digitally transforming civil engineering processes used in construction, surveying and infrastructure inspection markets with fully automated, highly precise, cost effective and safe tools. It utilizes state-of-the-art image processing and advanced drones and camera technologies dramatically reducing the amount of time surveying crews spend in the field, speeding up construction progress checks and shortening infrastructure inspection duration, while maintaining survey grade accuracy. The intuitive, simple and automated solutions increase productivity by saving field and office time in civil engineering and inspection projects of roads, intersections, stockpile volumes, topography, piping, industrial facilities, bridges, property surveys, building facades, railways, cellular infrastructure …


Assessing The Benefits Of Performance-Based Navigation Procedures, Kabir O. Kasim Oct 2017

Assessing The Benefits Of Performance-Based Navigation Procedures, Kabir O. Kasim

Journal of Aviation Technology and Engineering

Performance-based Navigation (PBN) allows aviation operations to be conducted based on actual operational requirements rather than the requirements of ground-based equipment. Although the general operational benefits of PBN procedures have been recognized by various studies, there is a need to specify the actual benefits in terms of the frequency of event anomalies that could be expected from the use of PBN procedures. The study reviewed some of the available literature and identified some operational improvements as reported by previous authors. The study then proceeded to review archival data from the Aviation Safety Reporting System (ASRS) database with a view to …


Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic Sep 2017

Design Of Dc-Link Vscf Ac Electrical Power System For The Embraer 190/195 Aircraft, Eduardo Francis Carvalho Freitas, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

A proposed novel DC-Link VSCF AC-DC-AC electrical power system converter for Embraer 190/195 transport category airplane is presented. The proposed converter could replace the existing conventional system based on the CSCF IDGs. Several contemporary production airplanes already have VSCF as a major or backup source of electrical power. Problems existed with the older VSCF systems in the past; however, the switched power electronics and digital controllers have matured and can be now, in our opinion, safely integrated and replace existing constant-speed hydraulic transmissions powering CSCF AC generators. IGBT power transistors for medium-level power conversion and relatively fast efficient switching are …


Vfr-Into-Imc: An Analysis Of Two Training Protocols On Weather-Related Posttest Scores, Julius C. Keller, Thomas Carney, Allen Xie, Wesley Major, Matt Price Sep 2017

Vfr-Into-Imc: An Analysis Of Two Training Protocols On Weather-Related Posttest Scores, Julius C. Keller, Thomas Carney, Allen Xie, Wesley Major, Matt Price

Journal of Aviation Technology and Engineering

According to the Aircraft Owners and Pilots Association Air Safety Institute, 264 accidents were identified as continued visual flight rules (VFR) into instrument meteorological conditions (IMC), during the past ten years. Approximately 89% of those VFR-into-IMC accidents were fatal, causing hundreds of deaths. VFR-into-IMC has been a major concern for the general aviation community, prompting focused efforts. Research, data analyses, outreach, training, and education are recommended practices to address risks associated with VFR-into-IMC. Researchers of the current study sought to evaluate the cause and effect relationship between two training protocols and weather-related posttest scores. A pretest–posttest experimental design was utilized …


Approaches To Integrating Engineering In Stem Units And Student Achievement Gains, Elizabeth A. Crotty, Selcen S. Guzey, Gillian H. Roehrig, Aran W. Glancy, Elizabeth A. Ring-Whalen, Tamara J. Moore Sep 2017

Approaches To Integrating Engineering In Stem Units And Student Achievement Gains, Elizabeth A. Crotty, Selcen S. Guzey, Gillian H. Roehrig, Aran W. Glancy, Elizabeth A. Ring-Whalen, Tamara J. Moore

Journal of Pre-College Engineering Education Research (J-PEER)

This study examined different approaches to integrating engineering practices in science, technology, engineering, and mathematics (STEM) curriculum units. These various approaches were correlated with student outcomes on engineering assessment items. There are numerous reform documents in the USA and around the world that emphasize the need to incorporate engineering into science education. The authors of this study contend that different approaches to integrating engineering in STEM units correlate to larger student achievement gains in engineering, based on assessment items developed from the Framework for Quality K–12 Engineering Education (Moore, Glancy, Tank, Kersten, & Smith, 2014). The goal of this work …


Molecular Structure And Confining Environment Of Sn Sites In Single-Site Chabazite Zeolites, James W. Harris, Wei-Chih Liao, John R. Di Iorio, Alisa M. Henry, Ta-Chung Ong, Aleix Comas-Vives, Christopher Coperet, Rajamani Gounder Sep 2017

Molecular Structure And Confining Environment Of Sn Sites In Single-Site Chabazite Zeolites, James W. Harris, Wei-Chih Liao, John R. Di Iorio, Alisa M. Henry, Ta-Chung Ong, Aleix Comas-Vives, Christopher Coperet, Rajamani Gounder

School of Chemical Engineering Faculty Publications

Chabazite (CHA) molecular sieves, which are industrial catalysts for the selective reduction of nitrogen oxides and the conversion of methanol into olefins, are also ideal materials in catalysis research because their crystalline frameworks contain one unique tetrahedral-site. The presence of a single lattice site allows for more accurate descriptions of experimental data using theoretical models, and consequently for more precise structure-function relationships of active sites incorporated into framework positions. A direct hydrothermal synthesis route to prepare pure-silica chabazite molecular sieves substituted with framework Sn atoms (Sn-CHA) is developed, which is required to predominantly incorporate Sn within the crystalline lattice. Quantitative …


New Fractals For Computer Generated Art Created By Iteration Of Polynomial Functions Of A Complex Variable, Charles F. Babbs Sep 2017

New Fractals For Computer Generated Art Created By Iteration Of Polynomial Functions Of A Complex Variable, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

Novel fractal forms can be created by iteration of higher order polynomials of the complex variable, z, with both positive and negative exponents, followed by optional integer power transformation, k zz . Such functions lead to an expanded universe of fascinating fractal patterns that can be incorporated into computer generated art.


Generalized Fractals For Computer Generated Art: Preliminary Results, Charles F. Babbs Sep 2017

Generalized Fractals For Computer Generated Art: Preliminary Results, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

This paper explores new types of fractals created by iteration of the functions xn+1 = f1(xn, yn) and yn+1 = f2(xn, yn) in a general plane, rather than in the complex plane. Iteration of such functions generates orbits with novel fractal patterns. Especially interesting are N-th order polynomials, raised to a positive or negative integer power, p.

Such functions create novel fractal patterns, including budding, spiked, striped, dragon head, and bat-like forms. The present faculty working paper shows how to create a rich variety of complex and fascinating fractals using this generalized approach, which is accessible to students with high …