Engineering Commons^™

Photovoltaic Material Characterization With Steady-State And Transient Photoluminescence, Xufeng Wang, Jayprakash Bhosale, James Moore, Rehan Kapadia, Peter Bermel, Ali Javey, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

In this study, we develop an approach to characterize the surface and bulk properties for thin films of photovoltaic materials by combining two experimental photoluminescence (PL) techniques with one multiphysics simulation. This contactless, in-line characterization technique allows reliable extraction of key lifetime parameters. In this study, we first discuss the strengths and weaknesses of both steady-state and transient PL techniques (specifically, steady-state PL excitation spectroscopy and time-resolved PL) and show that combining them with numerical simulation can be used to extract surface and bulk lifetimes self consistently. The method is applied to InP thin films grown with a novel vapor-liquid-solid …

Emission-Diffusion Theory Of The Mosfet, Mark S. Lundstrom, Supriyo Datta, Xingshu Sun

Department of Electrical and Computer Engineering Faculty Publications

An emission-diffusion theory that describes MOSFETS from the ballistic to diffusive limits is developed. The approach extends the Crowell-Sze treatment of metalsemiconductor junctions to MOSFETs and is equivalent to the scattering/transmission model of the MOSFET. The paper demonstrates that the results of the transmission model can be obtained from a traditional, drift-diffusion analysis when the boundary conditions are properly specified, which suggests that traditional drift-diffusion MOSFET models can also be extended to comprehend ballistic limits.

Mass Media And The Contagion Of Fear: The Case Of Ebola In America, Sherry M J Towers, Shehzad Afzal, Gilbert Bernal, Nadya T. Bliss, Baltazar Espinoza, Jasmine Jackson, Julia Judson-Garcia, Maryam Khan, Michael Lin, Robert Mamada, Victor M. Moreno, Fereshteh Nazari, Kamaldeen Okumeye, Mary L. Ross, Claudia Rodriguez, Jan Medlock, David S. Ebert, Carlos Castillo-Chavez,

Department of Electrical and Computer Engineering Faculty Publications

Background: In the weeks following the first imported case of Ebola in the U. S. on September 29, 2014, coverage of the very limited outbreak dominated the news media, in a manner quite disproportionate to the actual threat to national public health; by the end of October, 2014, there were only four laboratory confirmed cases of Ebola in the entire nation. Public interest in these events was high, as reflected in the millions of Ebola-related Internet searches and tweets performed in the month following the first confirmed case. Use of trending Internet searches and tweets has been proposed in the …

The Origin Of Korotkoff Sounds And The Accuracy Of Auscultatory Blood Pressure Measurements, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This study explores the hypothesis that the sharper, high frequency Korotkoff sounds come from resonant motion of the arterial wall, which begins after the artery transitions from a buckled state to an expanding state. The motion of one mass, two nonlinear springs, and one damper, driven by transmural pressure under the cuff, are used to model and compute the Korotkoff sounds according to principles of classical Newtonian physics. The natural resonance of this spring-mass-damper system provides a concise, yet rigorous, explanation for the origin of Korotkoff sounds. Fundamentally, wall stretching in expansion requires more force than wall bending in buckling. …

Civil Engineering/ Graduate Students/ Johnston & Jeffryes/ University Of Minnesota/ 2012, Lisa Johnston, Jon Jeffryes

Data Information Literacy Case Study Directory

From the University of Minnesota, this case study describes the seven modules that comprise their data information literacy program for students in Civil Engineering. The modules include: data management, organization and documentation, data access and ownership, data sharing and re-use, and preservation. Materials include a book chapter describing the case study, the syllabus for the program, a template for developing a data management plan and the evaluation forms that were used.

Eco-Design Integration Into New Product Development Processes: Comparison Between Lca Software And Cad-Integrated Tools, Maria I. Hernandez Dalmau

Purdue Polytechnic Masters Theses

The constant growth of environmental concerns and in order to satisfy the increasing population demands, designers have started to integrate eco-design parameters in early design stages. The technological development that happened in the last decade has started to integrate LCA methods within CAD tools, allowing non-geometric data to be integrated in a typical geometrical model. The main research interest of this thesis is focused on the evaluation of the use of these emerging CAD tools, as tools capable to evaluate the futures environmental impacts of products and processes. This thesis studies through three comparative case studies if SolidWorks Sustainability as …

Agriculture And Biological Engineering/ Graduate Students/ Bracke & Fosmire/ Purdue University/ 2012, Marianne S. Bracke, Michael Fosmire

Data Information Literacy Case Study Directory

This case study was comprised of three workshops for a lab in Agricultural and Biological Engineering. Data Information Literacy topics covered include developing and following a standard operating procedure, search for external data and creating metadata. Materials include a book chapter describing the case study, a data archiving checklist to follow for describing the types of data generated by the lab, a metadata entry form and an evaluation form used to gather feedback for each of the three sessions.

Electrical And Computer Engineering/ Undergraduates/ Carlson & Sappnelson/ Purdue University/ 2012, Jake Carlson, Megan R. Sapp Nelson

Data Information Literacy Case Study Directory

This is a case study of a semester long data information literacy program employing an embedded librarian approach to teach students competencies in describing, organizing and documenting their work in developing software code. Materials include a book chapter describing the case study, a rubric for evaluating software code and its accompanying documentation, a handout to introduce the program to teaching assistants, a lesson plan for a skills session on documenting software code, and a list of possible activities to encourage good practice in describing and documenting code.

Quantifying Benefits Of Signal Timing Maintenance And Optimization Using Both Travel Time And Travel Time Reliability Measures, Howell Li, Steven M. Lavrenz, Christopher M. Day, Amanda Stevens, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

High-Resolution Controller Data Performance Measures For Optimizing Diverging Diamond Interchanges And Outcome Assessment With Drone Video, Alexander M. Hainen, Amanda L. Stevens, Christopher M. Day, Howell Li, Jamie Mackey, Matt Luker, Mark Taylor, James R. Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Characterizing Signalized Intersection Performance Using Maximum Vehicle Delay, Steven M. Lavrenz, Christopher M. Day, Alexander M. Hainen, W Benjamin Smith, Amanda L. Stevens, Howell Li, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

Sequence Optimization At Signalized Diamond Interchanges Using High-Resolution Event-Based Data, Alexander M. Hainen, Howell Li, Amanda L. Stevens, Christopher M. Day, Jim Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

No abstract provided.

What Do Students Experience As Peer Leaders Of Learning Teams?, Eric C. Johnson, Brett A. Robbins, Michael Loui

School of Engineering Education Faculty Publications

In a course for engineering freshmen, peer leaders facilitated optional study sessions, which implemented peer-led team learning workshops. Some leaders were paid teaching assistants, but most were undergraduate volunteers. To understand the experiences of the peer leaders, we asked them to keep weekly reflective journals. By performing a basic qualitative analysis of fourteen journals from two semesters, we developed a description of the experience of leading peer-led team learning workshops over the course of the semester. At the beginning of the semester, the leaders were apprehensive about teaching and concerned with correctly answering students’ questions. As the semester progressed, the …

Simultaneous X-Ray Diffraction And Phase-Contrast Imaging For Investigating Material Deformation Mechanisms During High-Rate Loading, M Hudspeth, T Sun, N Parab, Z Guo, K Fezzaa, S Luo, Weinong W. Chen

Purdue Energetics Research Center Articles

No abstract provided.

New Challenges For The Archiving Of Digital Writing, Heiko Zimmermann

CLCWeb: Comparative Literature and Culture

In his article "New Challenges for the Archiving of Digital Writing" Heiko Zimmermann discusses the challenges of the preservation of digital texts. In addition to the problems already at the focus of attention of digital archivists, there are elements in digital literature which need to be taken into consideration when trying to archive them. Zimmermann analyses two works of digital literature, the collaborative writing project A Million Penguins (2006-2007) and Renée Tuner's She… (2008) and shows how the ontology of these texts is bound to elements of performance, to direct social interaction of writers and readers to the uniquely subjective …

Towards Digital Art In Information Society, Montse Arbelo, Joseba Franco

CLCWeb: Comparative Literature and Culture

In their article "Towards Digital Art in Information Society" Montse Arbelo and Joseba Franco propose the development of the platform of a Network of Experimental Centers be formed by small groups of people who are qualified and who seek optimal operational effectiveness and who dedicate their resources to the production of digital content and we offer artechmedia <http://www.artechmedia.org> as a base point of departure. Such an international network in a collaborative structure based on national networks would make possible to coordinate existing resources to develop social networks, generate and promote content, engage in forums of discussion and creativity workshops, and …

Ontogenetic Scaling Patterns And Functional Anatomy Of The Pelvic Limb Musculature In Emus (Dromaius Novaehollandiae), Luis P. Lamas, Russell P. Main, John R. Hutchinson

Department of Basic Medical Sciences Faculty Publications

Emus (Dromaius novaehollandiae) are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive, as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric) analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths) and calculated muscle physiological cross sectional area …

Two-Dimensional Layered Mos2 Biosensors Enable Highly Sensitive Detection Of Biomolecules, Joonhyung Lee, Piyush Dak, Yeonsung Lee, Heekyeong Park, Woong Choi, Muhammad Ashraful Alam, Sunkook Kim

Birck and NCN Publications

We present a MoS₂ biosensor to electrically detect prostate specific antigen (PSA) in a highly sensitive and label-free manner. Unlike previous MoS₂-FET-based biosensors, the device configuration of our biosensors does not require a dielectric layer such as HfO₂ due to the hydrophobicity of MoS₂. Such an oxide-free operation improves sensitivity and simplifies sensor design. For a quantitative and selective detection of PSA antigen, anti-PSA antibody was immobilized on the sensor surface. Then, introduction of PSA antigen, into the anti-PSA immobilized sensor surface resulted in a lable-free immunoassary format. Measured off-state current of the device …

Privacy-Preserving And Outsourced Multi-User K-Means Clustering, Bharath Samanthula, Fang-Yu Rao, Elisa Bertino, Xun Yi, Dangxi Liu

Cyber Center Publications

Many techniques for privacy-preserving data mining (PPDM) have been investigated over the past decade. Often, the entities involved in the data mining process are end-users or organizations with limited computing and storage resources. As a result, such entities may want to refrain from participating in the PPDM process. To overcome this issue and to take many other benefits of cloud computing, outsourcing PPDM tasks to the cloud environment has recently gained special attention. We consider the scenario where n entities outsource their databases (in encrypted format) to the cloud and ask the cloud to perform the clustering task on their …

Traffic Safety Primer For Local Agencies, Indiana Ltap, Michigan Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

The purpose of this booklet is to empower local agency personnel to make informed decisions that can improve roadway safety in your community. By identifying and addressing potential roadway hazards, you can reduce the likelihood of a future traffic crash for your community and your family. Adapted by permission from the Michigan LTAP’s 2008 Publication What Elected Officials Need to Know About Traffic Safety (And What YOUR Constituents Expect YOU to Know!)

Impact Profile: Tech 120-Nathan Mentzer, Jason A. Ware

IMPACT Profile Directory

This profile highlights the course redesign and transformation of a foundational first-year course in Purdue University’s College of Technology. The faculty involved in this redesign were focused primarily on accomplishing two things with the course transformation. First, faculty recognized that the initial course objectives focused on students learning general skills that are taught throughout the University – career awareness and study skills. The goal with the course redesign was for students to learn skills that are unique to the fields of study within the College and for students to experience a student-centered pragmatic approach to teaching and learning. Second, faculty …

Students’ Perceptions Of And Responses To Teaching Assistant And Peer Feedback, Kelsey J. Rodgers, Aladar K. Horvath, Hyunyi Jung, Amanda S. Fry, Heidi Diefes-Dux, Monica E. Cardella

Interdisciplinary Journal of Problem-Based Learning

Authentic open-ended problems are increasingly appearing in university classrooms at all levels. Formative feedback that leads to learning and improved student work products is a challenge, particularly in large enrollment courses. This is a case study of one first-year engineering student team’s experience with teaching assistant and peer feedback during a series of open-ended mathematical modeling problems called Model-Eliciting Activities. The goal of this study was to gain deep insight into the interactions between students, feedback providers, and written feedback by examining one team’s perceptions of the feedback they received and the changes they made to their solutions based on …

Poster: Protecting Against Data Exfiltration Insider Attacks Through Application Programs, Asmaa Mohamed Sallama, Elisa Bertino

Cyber Center Publications

In this paper, we describe a system that distinguishes be- tween legitimate and malicious database transactions per- formed by application programs. Our system is particularly useful for protecting against code-modification attacks performed by insiders who have access to and can change the programs' source code to make them execute different queries than those they are expected to execute. Our system works with any type of DBMS and requires minimum modification to application programs.

Best Practices In Trail Maintenance, Indiana Ltap, Ohio River Greenway Development Commission

Indiana Local Technical Assistance Program (LTAP) Publications

This manual is intended for practical use by trail maintenance managers. It will also be useful for policy makers who are tasked with anticipating and planning for maintenance budget and personnel needs. The recommendations included in this manual were chosen, in part, to facilitate widespread adoption by other trail operators. They are cost-effective solutions that require minimal technological or financial commitments.

This manual does not provide guidance for trail construction and design, except where a maintenance issue can best be resolved by constructing new trail segments. For best practices in design and construction, consult the thorough list of resources provided …

Driven By Beliefs: Understanding Challenges Physical Science Teachers Face When Integrating Engineering And Physics, Emily A. Dare, Joshua A. Ellis, Gillian H. Roehrig

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

It is difficult to ignore the increased use of technological innovations in today’s world, which has led to various calls for the integration of engineering into K-12 science standards. The need to understand how engineering is currently being brought to science classrooms is apparent and necessary in order to address these calls for integration. This multiphase, mixed-methods study investigated the classroom practices and beliefs of high school physical science teachers following an intensive professional development on physics and engineering integration.

Classroom observations showed that teachers new to incorporating engineering into their physical science classrooms often struggled to maintain focus on …

Design Practices Of Preservice Elementary Teachers In An Integrated Engineering And Literature Experience, Kristen Bethke Wendell

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

The incorporation of engineering practices and core ideas into the Next Generation Science Standards at the elementary school level provides exciting opportunities but also raises important questions about the preparation of new elementary teachers. Both the teacher education and engineering education communities have a limited literature base on the resources that novice elementary teachers bring to learning and teaching engineering. The purpose of this descriptive exploratory research study was to characterize the design practices used by preservice elementary teachers during an integrated engineering and literature experience. Using a modification of the Design Activity Coding Scheme (Atman et al., 2007), we …

High And Low Computer Self-Efficacy Groups And Their Learning Behavior From Self-Regulated Learning Perspective While Engaged In Interactive Learning Modules, Harry B. Santoso, Oenardi Lawanto, Kurt Becker, Ning Fang, Edward M. Reeve

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

The purpose of this research was to investigate high school students’ computer self-efficacy (CSE) and learning behavior in a selfregulated learning (SRL) framework while utilizing an interactive learning module. The researcher hypothesizes that CSE is reflected on cognitive actions and metacognitive strategies while the students are engaged with interactive learning modules. Two research questions guided this research: (1) how is students’ CSE while engaged in interactive learning modules? and (2) how do high and low CSE groups plan and monitor their cognitive action, and regulate their monitoring strategies based on their CSE level? The research used a mixedmethods approach to …

Gender Differences In The Consistency Of Middle School Students’ Interest In Engineering And Science Careers, Marsha Ing, Pamela R. Aschbacher, Sherry M. Tsai

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

This longitudinal study analyzes survey responses in seventh, eighth, and ninth grade from diverse public school students (n = 482) to explore gender differences in engineering and science career preferences. Females were far more likely to express interest in a science career (31%) than an engineering career (13%), while the reverse was true for males (58% in engineering, 39% in science). After controlling for student and school demographic characteristics, females were as consistent as males in their science career interests during the three years of the study but less consistent in their engineering career interests. Knowing an engineer significantly …

Field Cycle Length Sweep To Evaluate Resonant Cycle Sensitivity, Howell Li, Christopher M. Day, Alex M. Hainen, Amanda L. Stevens, Steven Lavrenz, W Benjamin Smith, Hayley Summers, Rick Freije, Jim Sturdevant, Darcy M. Bullock

JTRP Other Publications and Reports

Cycle length selection in corridor timing is often dictated by critical intersections with the highest level of saturation. Along corridors with balanced volumes and favorable link distances, a resonant cycle length is often sought to provide good progression in both directions of travel. This paper discusses the search for a resonant cycle length at a 5-intersection corridor in Fishers, Indiana over a three month period. The software traffic model suggests a reasonable range of cycle lengths from 104 seconds to 124 seconds for the corridor. This cycle length range is consistent with analytical highway capacity manual delay minimization approaches.

A …

Investigation And Modeling Of Uranium Polarization For The Electrorefining Of Scrap U-Mo Foils, Melissa Rose

Open Access Dissertations

A uranium molybdenum alloy fuel has been proposed to convert research and test reactors from highly enriched uranium to low enriched uranium to increase the proliferation resistance at such reactors. Pyroprocessing has been selected to recover uranium from the scrap produced in the manufacture of this novel fuel type. Electrorefining, the main separation process of pyroprocessing, is modeled through a novel approach using corrosion theory. To use corrosion theory, knowledge of uranium polarization and kinetic parameters such as Tafel constant, transfer coefficient and exchange current density are required. Uranium polarization was investigated at five temperatures and three scan rates in …