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Pltw And Epics‐High: Curriculum Comparisons To Support Problem Solving In The Context Of Engineering Design, Todd Kelley, Daniel C. Brenner, John T. Pieper 2010 Utah State University

Pltw And Epics‐High: Curriculum Comparisons To Support Problem Solving In The Context Of Engineering Design, Todd Kelley, Daniel C. Brenner, John T. Pieper

Reports of Center Studies

A comparative study was conducted to compare two approaches to engineering design curriculum between different schools (inter-school) and between two curricular approaches, Project Lead the Way (PLTW) and Engineering Projects in Community Service (EPIC High) (inter-curricular). The researchers collected curriculum materials, including handouts, lesson plans, guides, presentation files, design descriptions, problem statements, and support guides. The researchers conducted observations in the classrooms to collect qualitative indicators of engineering/technology reasoning, collect data on the nature of students‟ questions, how students define problems, and operate within the constraints of a design problem.

Observational studies were conducted with students participating in Project ...


Design Assessment: Consumer Reports Style, Todd R. Kelley 2010 Purdue University

Design Assessment: Consumer Reports Style, Todd R. Kelley

Publications

The article analyzes a design assessment-based activity, in which students are asked to evaluate an existing technology through a Consumer Reports-style approach. According to H. Petroski, the exposure of students to several design examples is important to start learning the basic elements needed in the design process. It claims that the activity will enable students to sharpen their knowledge in several areas including identifying design constraints and criteria, training via study of open designs, and practicing engineering design methods for optimization. It suggests that these are important skills for creating the student's capacity to undertake bigger design activities.


Stem Education And Leadership: A Mathematics And Science Partnership Approach, Chris Merrill, Jenny Daugherty 2010 Illinois State University

Stem Education And Leadership: A Mathematics And Science Partnership Approach, Chris Merrill, Jenny Daugherty

Publications

The issue of attracting more young people to choose careers in science, technology, engineering, and mathematics (STEM) has become critical for the United States. Recent studies by businesses, associations, and education have all agreed that the United States’ performance in the STEM disciplines have placed our nation in grave risk of relinquishing its competitive edge in the marketplace (e.g., Rising above the gathering storm, 2007). A Congressional Research Service (2006) report stated that, a “large majority of secondary students fail to reach proficiency in math and science, and many are taught by teachers lacking adequate subject matter knowledge” (Congressional ...


Engineering Professional Development Design For Secondary School Teachers: A Multiple Case Study, Jenny L. Daugherty 2010 Purdue University

Engineering Professional Development Design For Secondary School Teachers: A Multiple Case Study, Jenny L. Daugherty

Publications

The effectiveness of teachers has been regarded as crucial to the success of standards-based reform (Fishman, Marx, Best, & Tal, 2003). Research, particularly within science and mathematics, has underscored the need for professional development to help teachers understand (a) subject matter, (b) learners and learning, and (c) teaching methods (Loucks-Horsley, 1999). In addition to focusing on teacher professional development, national reform efforts have also emphasized science, technology, engineering, and mathematics (STEM) education (i.e., Rising Above the Gathering Storm, NRC, 2006). While substantial work has been conducted in mathematics and science, the efforts in technology and engineering education are much less mature. This makes sense given the relatively recent development of the Standards for Technological Literacy (ITEA, 2000) and recent calls for integrating engineering into the K-12 classroom as both an avenue to technological literacy and as a way to enhance the engineering pipeline (Erekson & Custer, 2008; Lewis, 2005; Wicklein, 2006).

The complexity of engineering and its integration into K-12 education, however, have resulted in a variety of issues requiring sustained empirical research (Johnson, Burghardt, & Daugherty, 2008). One particular area of need given the emphasis on teacher effects on student learning is to research engineering-oriented teacher professional development. A lack of publication on the effective practices of engineering-specific professional development projects makes a study investigating mature efforts necessary. Thus, the purpose of this qualitative study was to explore professional ...


Compact Survey And Inspection Day/Night Image Sensor Suite For Small Unmanned Aircraft Systems (Eyepod), Alan Bird, Scott A. Anderson, Dale Linne von Berg, Morgan Davidson, Niel Holt, Melvin Kruer, Michael L. Wilson 2010 Utah State University

Compact Survey And Inspection Day/Night Image Sensor Suite For Small Unmanned Aircraft Systems (Eyepod), Alan Bird, Scott A. Anderson, Dale Linne Von Berg, Morgan Davidson, Niel Holt, Melvin Kruer, Michael L. Wilson

Space Dynamics Lab Publications

EyePod is a compact survey and inspection day/night imaging sensor suite for small unmanned aircraft systems (UAS). EyePod generates georeferenced image products in real-time from visible near infrared (VNIR) and long wave infrared (LWIR) imaging sensors and was developed under the ONR funded FEATHAR (Fusion, Exploitation, Algorithms, and Targeting for High-Altitude Reconnaissance) program. FEATHAR is being directed and executed by the Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL) and FEATHAR’s goal is to develop and test new tactical sensor systems specifically designed for small manned and unmanned platforms (payload weight < 50 lbs). The EyePod suite consists of two VNIR/LWIR (day/night) gimbaled sensors that, combined, provide broad area survey and focused inspection capabilities. Each EyePod sensor pairs an HD visible EO sensor with a LWIR bolometric imager providing precision geo-referenced and fully digital EO/IR NITFS output imagery. The LWIR sensor is mounted to a patent-pending jitter-reduction stage to correct for the high-frequency motion typically found on small aircraft and unmanned systems. Details will be presented on both the wide-area and inspection EyePod sensor systems, their modes of operation, and results from recent flight demonstrations.


Anterior-Posterior Impedance Cardiography: A New Approach To Accurate, Non-Invasive Monitoring Of Cardiac Function, Charles F. Babbs 2010 Purdue University

Anterior-Posterior Impedance Cardiography: A New Approach To Accurate, Non-Invasive Monitoring Of Cardiac Function, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

The conventional impedance cardiogram is a record of pulsatile changes in the electrical impedance of the chest with each heartbeat. The signal seems intuitively related to cardiac stroke volume. However doubts persist about the validity of stroke volume measurements based on electrical impedance. This paper presents a new electrical axis for impedance cardiography that is perpendicular to the conventional head-to-foot axis in an anterior-posterior direction. Dual chest and back electrodes are concentric, permitting tetrapolar technique. A relatively simple analytical model is developed, and this model is validated in a three-dimensional finite element model of current flow through the human chest ...


Automated Tank Surface Finishing System, Purdue ECT Team 2010 Purdue University

Automated Tank Surface Finishing System, Purdue Ect Team

ECT Fact Sheets

The current finishing techniques are costly and laborious, and they expose workers to significant health and safety risks. The automated tank surface finishing system uses a computer-controlled motion module to refinish the vertical exterior walls of a tank. The module is configurable for both blasting and painting and utilizes conventional surface finishing equipment for these processes. An overspray hood is included to reduce contamination of the surrounding environment during painting. The module attaches to a tank’s wind girts with steel cables, and its position and velocity are controlled by servo-driven hoists.


Appia® – Construction Management Web Application, Purdue ECT Team 2010 Purdue University

Appia® – Construction Management Web Application, Purdue Ect Team

ECT Fact Sheets

The Appia® software is a hosted web application for construction program administration. The Appia system can manage the business processes in the major functional areas of the project life-cycle – estimation, bid management and construction – due to its flexible configuration and customizable business rules, providing organizations the opportunity to simplify and standardize their processes.


2010 Enacted Wheel Tax Rates (Lohut), Indiana LTAP 2010 Purdue University

2010 Enacted Wheel Tax Rates (Lohut), Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

This publication is a compilation of wheel tax rates using data provided by the Indiana Bureau of Motor Vehicles.


Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Shailaja Pandit, Adri C. T. van Duin, Ananth Y. Grama 2010 Purdue University - Main Campus

Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Shailaja Pandit, Adri C. T. Van Duin, Ananth Y. Grama

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

Modeling atomic and molecular systems requires computation-intensive quantum mechanical methods such as, but not limited to, density functional theory (DFT) [11]. These methods have been successful in predicting various properties of chemical systems at atomistic detail. Due to the inherent nonlocality of quantum mechanics, the scalability of these methods ranges from O(N3) to O(N7) depending on the method used and approximations involved. This significantly limits the size of simulated systems to a few thousands of atoms, even on large scale parallel platforms. On the other hand, classical approximations of quantum systems, although computationally (relatively) easy to implement, yield ...


Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, Ajit K. Vallabhaneni, Jeffrey F. Rhoads, Xiulin Ruan, Jayathi Y. Murthy 2010 Purdue University - Main Campus

Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, Ajit K. Vallabhaneni, Jeffrey F. Rhoads, Xiulin Ruan, Jayathi Y. Murthy

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

This work examines the quality factors (Q factors) of resonance associated with the axial and transverse vibrations of single-wall carbon nanotube (SWCNT) resonators through the use of molecular dynamics (MD) simulation. Specifically, the work investigates the effect of device length, diameter, and chirality, as well as temperature, on the resonant frequency and quality factor of these devices, and benchmarks the results of MD simulation against classical theories of energy dissipation. Of note are the facts that the quality factors associated with transverse vibration decrease with increasing device diameter and are largely insensitive to chirality. Additionally, quality factors increase with increasing ...


Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface, Adam Fruehling, Mohammad Abu Khater, Byunghoo Jung, Dimitrios Peroulis 2010 Purdue University - Main Campus

Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface, Adam Fruehling, Mohammad Abu Khater, Byunghoo Jung, Dimitrios Peroulis

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

This paper presents the first ultra-low power, fully electronic methodology for real-time monitoring of the dynamic behavior of RF MEMS switches. The measurement is based on a capacitive readout circuit composed of 67 transistors with 105 µm x 105 µm footprint consuming as little as 60 µW. This is achieved by accurately sensing the capacitance change around the contact region at sampling rates from 10 kHz to 5 MHz. Experimental and simulation results show that times of not only the first contact event but also all subsequent contact bounces can be accurately measured with this technique without interfering with the ...


A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, Hao-Han Hsu, Dimitrios Peroulis 2010 Purdue University - Main Campus

A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, Hao-Han Hsu, Dimitrios Peroulis

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

In this paper we present, for the ¯rst time, an experimentally-extracted model for the spring con- stant and tuning range of an analog RF-MEMS var- actor that includes viscoelastic e®ects in RF-MEMS devices. By utilizing a bi-state bias condition with one state lasting 60 minutes and the other 1 minute, this model focuses on capturing the true electrome- chanical behavior of the varactor. An experimental setup with very high long-term accuracy is created to measure capacitance of the varactor up to 1,370 hours. The impact of these e®ects and the e®ective- ness of the model are ...


Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers, Murat Manguoglu, Mehmet Koyuturk, Ahmed Sameh, Ananth Y. Grama 2010 Purdue University - Main Campus

Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers, Murat Manguoglu, Mehmet Koyuturk, Ahmed Sameh, Ananth Y. Grama

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

The emergence of multicore architectures and highly scalable platforms motivates the development of novel algorithms and techniques that emphasize concurrency and are tolerant of deep memory hierarchies, as opposed to minimizing raw FLOP counts. While direct solvers are reliable, they are often slow and memory-intensive for large problems. Iterative solvers, on the other hand, are more efficient but, in the absence of robust preconditioners, lack reliability. While preconditioners based on incomplete factorizations ( whenever they exist) are effective for many problems, their parallel scalability is generally limited. In this paper, we advocate the use of banded preconditioners instead and introduce a ...


Assessment Of Benthic Flux Of Dissolved Organic Carbon In Estuaries Using The Eddy Correlation Technique, Michael P. Swett 2010 University of Maine - Main

Assessment Of Benthic Flux Of Dissolved Organic Carbon In Estuaries Using The Eddy Correlation Technique, Michael P. Swett

Electronic Theses and Dissertations

Dissolved organic carbon (DOC) is a water quality concern in estuarine environments, as DOC facilitates mobilization of metals and organics in sediments and leads to toxic disinfection byproducts during water treatment. Export of DOC from sediments can vary with changing environmental conditions, including wetland restoration and rising sea levels. Therefore, it is important to quantify flux of DOC across the sediment-water interface (SWI). Existing DOC flux measurement techniques, such as equilibrium dialysis, porewater extraction, and benthic chamber measurement, are intrusive to the sediment environment and underestimate flux by only capturing certain flux contributions. In this research, methods for estimating benthic ...


Multiscale Investigation Of Random Heterogenous Media In Materials And Earth Sciences, Andrew J. Goupee 2010 The University of Maine

Multiscale Investigation Of Random Heterogenous Media In Materials And Earth Sciences, Andrew J. Goupee

Electronic Theses and Dissertations

This dissertation is concerned with three major areas pertaining to the characterization and analysis of heterogeneous materials. The first is focused on the modeling of heterogeneous materials with random microstructure and understanding their thermomechanical properties as well as developing a methodology for the multiscale thermoelastic analysis of random heterogeneous materials. Realistic random microstructures are generated for computational analyses using random morphology description functions. The simulated microstructures closely resemble actual micrographs of random heterogeneous materials. The simulated random microstructures are characterized using statistical techniques and their homogenized material properties computed using the asymptotic expansion homogenization method. The failure response of random ...


A Monolithic Spiral Coil Acoustic Transduction Sensor For Chemical And Biological Analytes, Donald F. McCann 2010 The University of Maine

A Monolithic Spiral Coil Acoustic Transduction Sensor For Chemical And Biological Analytes, Donald F. Mccann

Electronic Theses and Dissertations

Acoustic wave sensor platforms typically consist of piezoelectric materials in which bulk or surface acoustic waves are excited by metallic transducers deposited on the sensing surface of the platform. This type of transduction has limitations. In particular the transducer may limit the type of sensing film that can be used or analyte that can be measured and limit the frequency of operation of the sensor. In this work a novel method of exciting high frequency bulk acoustic waves in piezoelectric sensor platforms has been explored. This technique consists of applying time varying electromagnetic fields to the sensor platform using an ...


1.5-Ghz Cmos Voltage-Controlled Oscillator Based On Thickness-Field-Excited Piezoelectric A1n Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van der Spiegel, Gianluca Piazza 2010 University of Pennsylvania

1.5-Ghz Cmos Voltage-Controlled Oscillator Based On Thickness-Field-Excited Piezoelectric A1n Contour-Mode Mems Resonators, Chengjie Zuo, Jan Van Der Spiegel, Gianluca Piazza

Departmental Papers (ESE)

This paper reports on the first demonstration of the 1.5 GHz CMOS oscillator based on thickness-field-excited (TFE) piezoelectric AIN MEMS contour-mode resonators (CMRs). The measured phase noise is -85 dBc/Hz at 10 kHz offset frequency and -151 dBc/Hz at 1MHz. This is the highest frequency MEMS oscillator ever reported using a laterally vibrating mechanical resonator. The high frequency operation has been enabled by optimizing the geometrical design and micro-fabrication process of TFE AIN CMRs, so that a low effective motional resistance around 50 Ω is achieved together with a high unloaded quality factor (Qu) approaching 2500 ...


Security In Ad Hoc Networks And Pervasive Computing, Isaac Z. Wu, X.-Y. Li, M. Song, C.-M. Liu 2010 Old Dominion University

Security In Ad Hoc Networks And Pervasive Computing, Isaac Z. Wu, X.-Y. Li, M. Song, C.-M. Liu

Electrical & Computer Engineering Faculty Publications

Pervasive computing is an exciting and blooming research field, in which innovative techniques and applications are continuously emerging and aim to provide ambient and personalized services to users with high quality. Ad hoc networks are wireless, self-organizing systems formed by cooperating nodes within communication range of each other that form temporary networks. Their topology is dynamic, decentralized, ever changing and the nodes may move around arbitrarily. The last few years have witnessed a wealth of research ideas on ad hoc networking that are moving rapidly into implemented standards. Technology under development for ad hoc networks and pervasive computing is making ...


Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza 2010 University of Pennsylvania

Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza

Departmental Papers (ESE)

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) superhigh- frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contourextensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt^2, in excess of 1.5%. These devices ...


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