Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

2002

Series

Discipline
Institution
Keyword
Publication
File Type

Articles 1 - 30 of 1079

Full-Text Articles in Engineering

Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta Dec 2002

Optimal Pumping Strategies For Umatilla Chemical Depot Rdx And Tnt Plumes, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We present optimal pumping strategies to address RDX and TNT plumes at Umatilla Chemical Depot (UCD). We provide strategies for four optimization problem formulations. Each strategy requires constructing 2 wells. New Well U-1 is in the same location for all strategies. The second well location can differ with formulation. The number in a strategy’s name refers to the formulation it addresses. Using optimization in design is normally an iterative process involving interaction between the designer and client after preliminary optimizations are performed. This project does not permit that. To compensate, we present a second strategy for Formulation 1 (Strategy USU1B), …


Electrostatic Particle Separation System, Apparatus, And Related Method, John M. Stencel, John L. Schaefer, James K. Neathery, Heng Ban, Dennis Finseth Dec 2002

Electrostatic Particle Separation System, Apparatus, And Related Method, John M. Stencel, John L. Schaefer, James K. Neathery, Heng Ban, Dennis Finseth

Center for Applied Energy Research Faculty Patents

An electrostatic separation apparatus or system is provided for separating a particle mixture into two constituent species. The system includes a distributor for differentially tribocharging the particle species forming the mixture and supplying the charged mixture to a plurality of electrostatic separation cells. Each cell includes at least one separator having an inlet, a separation chamber having an electric field zone for drawing selected charged particles from the particle mixture, a collector, and a transition outlet. The length of the electric field zone is selectively adjustable for varying the charged particle drawing action. A curtain gas flow introduced into the …


Milliwatt Power Deep Ultraviolet Light-Emitting Diodes Over Sapphire With Emission At 278 Nm, J. P. Zhang, A. Chitnis, V. Adivarahan, S. Wu, V. Mandavilli, R. Pachipulusu, M. Shatalov, Grigory Simin, J. W. Yang, M. Asif Khan Dec 2002

Milliwatt Power Deep Ultraviolet Light-Emitting Diodes Over Sapphire With Emission At 278 Nm, J. P. Zhang, A. Chitnis, V. Adivarahan, S. Wu, V. Mandavilli, R. Pachipulusu, M. Shatalov, Grigory Simin, J. W. Yang, M. Asif Khan

Faculty Publications

We report on AlGaN multiple-quantum-well (MQW)-based deep ultraviolet light-emitting diodes over sapphire with peak emission at 278 nm. A new buffer layer growth process was used to reduce the number of defects and hence the nonradiative recombination. The improved material quality and carrier confinement resulted in pulsed powers as high as 3 mW at 278 nm and a significantly reduced deep-level-assisted long-wavelength emission.


Seismic Response Study Of Asymmetric Systems With Linear And Nonlinear Fluid Viscous Dampers, Rakesh K. Goel Dec 2002

Seismic Response Study Of Asymmetric Systems With Linear And Nonlinear Fluid Viscous Dampers, Rakesh K. Goel

Civil and Environmental Engineering

This investigation is concerned with application of nonlinear fluid viscous dampers for asymmetric-plan systems. For this purpose, the behavior of nonlinear fluid viscous dampers is summarized first followed by the effects of damper nonlinearity on seismic response of asymmetric systems. It is shown that the peak force in nonlinear damper tends to be smaller compared to linear damper. However, this is true only for values of V / ůo less that a certain threshold value; for larger values of V / ůo, the force in nonlinear damper may become larger· than that in the linear damper. While …


Chaotic Free-Space Laser Communication Over Turbulent Channel, N. F. Rulkov, Mikhail Vorontsov, L. Illing Dec 2002

Chaotic Free-Space Laser Communication Over Turbulent Channel, N. F. Rulkov, Mikhail Vorontsov, L. Illing

Electro-Optics and Photonics Faculty Publications

The dynamics of errors caused by atmospheric turbulence in a self-synchronizing chaos-based communication system that stably transmits information over a ∼5  km free-space laser link is studied experimentally. Binary information is transmitted using a chaotic sequence of short-term pulses as a carrier. The information signal slightly shifts the chaotic time position of each pulse depending on the information bit. We report the results of an experimental analysis of the atmospheric turbulence in the channel and the impact of turbulence on the bit-error-rate performance of this chaos-based communication system.


Dec 2002, Tractor Museum Dec 2002

Dec 2002, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Report from Director on Leave Development Projects Liason Report


Buffer Interference Architecture, Vladimir I. Prodanov Dec 2002

Buffer Interference Architecture, Vladimir I. Prodanov

Electrical Engineering

An up to 3× breakdown voltage tristate capable integrated circuit CMOS buffer includes a level shifter circuit and a driver circuit. The driver stage includes a series connected n-channel and p-channel cascode stacks, each including at least three transistors. Dynamic gate biasing is provided for the third n-channel and p-channel cascode transistors to prevent voltage overstress of the cascode transistors. The level shifter circuit includes at least one pseudo N-MOS inverter including an input transistor, a protective cascode stack including at least one n-channel cascode transistor, and a load transistor. The level shifter provides at least one voltage shifted input …


Terahertz-Driven Nonlinear Electrical Transport In Semiconductor Nanostructures, C. Zhang Dec 2002

Terahertz-Driven Nonlinear Electrical Transport In Semiconductor Nanostructures, C. Zhang

Faculty of Engineering - Papers (Archive)

In this work, we used the quantum transport equation and density matrix formalism to calculate the frequency dependent electrical current of a two-dimensional electron gas directly driven by an intense terahertz laser. It is found that due to increased electron-photon coupling, the electron-impurity scattering decreases rapidly with the electric field.


Selective Laser Excitation Spectroscopy Of Gallium And Phosphorous In Germanium, C. A. Freeth, R. A. Lewis Dec 2002

Selective Laser Excitation Spectroscopy Of Gallium And Phosphorous In Germanium, C. A. Freeth, R. A. Lewis

Faculty of Engineering - Papers (Archive)

Shallow impurity states of donors and acceptors in Ge have been investigated by far-infrared laser magnetospectroscopy. The Zeeman splitting of the impurity states produces resonant absorption of the laser radiation at certain magnetic fields. The data are compared to measurements made using a conventional spectrometer and good agreement is found.


On-Chip Actuation Of An In-Plane Compliant Bistable Micromechanism, Michael S. Baker, Larry L. Howell Dec 2002

On-Chip Actuation Of An In-Plane Compliant Bistable Micromechanism, Michael S. Baker, Larry L. Howell

Faculty Publications

A compliant bistable micromechanism has been developed which can be switched in either direction using on-chip thermal actuation. The energy storage and bistable behavior of the mechanism is achieved through the elastic deflection of compliant segments. The Pseudo-Rigid-Body Model was used for the compliant mechanism design, and for analysis of the large deflection flexible segments. To achieve on-chip actuation, the mechanism design was optimized to allow it to be switched using linear motion thermal actuators. The modeling theory and analysis are presented for three design iterations, with two iterations fabricated in the MUMP's process and the third in the SUMMiT …


An Assessment Of Seawinds On Quikscat Wind Retrieval, David Draper, David G. Long Dec 2002

An Assessment Of Seawinds On Quikscat Wind Retrieval, David Draper, David G. Long

Faculty Publications

The scatterometer ocean wind retrieval process produces several possible solutions or ambiguities at each point, requiring a separate ambiguity selection step to infer a unique wind vector field. An ambiguity selection error occurs when the selected wind vector is not the closest ambiguity to the true wind. The current ambiguity selection routine for SeaWinds is ad hoc, but performs well under most circumstances. Factors such as instrument noise and rain can also cause the estimated wind flow to deviate from the true wind. A quality assurance (QA) analysis is performed to assess the ambiguity selection effectiveness and noise level of …


An Optimum Greedy Algorithm For Choosing Minimal Set Of Conflicting Constraints In The Point Sequencing Problem, Florent Launay, Mitra Debasis Dec 2002

An Optimum Greedy Algorithm For Choosing Minimal Set Of Conflicting Constraints In The Point Sequencing Problem, Florent Launay, Mitra Debasis

Electrical Engineering and Computer Science Faculty Publications

In this work, we first have proposed a technique to define the "causes" of inconsistency on an online point based reasoning constraint network. Second, we introduce an algorithm that proposes the user a minimal set of relations to remove when inconsistencies are detected. We have developed and implemented a battery of algorithms for the purpose of this type of reasoning. Some useful theorems and properties are defined for proving the 'minimal' aspect of the algorithm. Finally, we found that our investigation was a polynomially solvable sub problem of the vertex cover problem.


Remote Experimental Station For Engineering Education, Muralidhar Doddapuneni Dec 2002

Remote Experimental Station For Engineering Education, Muralidhar Doddapuneni

FIU Electronic Theses and Dissertations

This thesis provides a distance-learning laboratory for students of electrical and computer engineering department where the instructor can conduct experiments on a computer and send the results to the students at remote computers. The output of the experiment conducted by the instructor is sampled using a successive approximation Analog to Digital (A/D) converter. A microcontroller collects samples using high speed queued serial peripheral interface clock and transmits data to IBM-compatible personal computer over a serial port interface, where the samples are processed using Fast Fourier Transforms and graphed. The client/server application developed transfers the acquired samples over Transmission Control Protocol/Internet …


Interactive Learning Tools: Animating Statics, Nancy Hubing, David B. Oglesby, Timothy A. Philpot, Vikas Yellamraju, Richard H. Hall, Ralph E. Flori Dec 2002

Interactive Learning Tools: Animating Statics, Nancy Hubing, David B. Oglesby, Timothy A. Philpot, Vikas Yellamraju, Richard H. Hall, Ralph E. Flori

Business and Information Technology Faculty Research & Creative Works

Computer-Based Modules for Engineering Instruction Must Be Concise, Flexible, Educational and Engaging in Order to Effectively Supplement Traditional Classroom Teaching Tools. a Computer Example that Takes More Time Than a Chalkboard Presentation is Not Likely to Be Useful in Today's Engineering Classroom. Flexible Navigation is Necessary So that the Instructor Can Quickly and Easily Respond to Student Questions. Useful Modules Must Also Improve Problem-Solving Skills or Clarify Troublesome Concepts in Order to Be Considered Worthy of Inclusion in the Limited Class Time Available. Finally, and Perhaps Most Importantly, Effective Computer-Based Modules Must Meet the Challenge of Holding the Student's Attention. …


Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada Dec 2002

Osaka University: A Focus Of Polymer Science: 70th Anniversary Celebration, Otto Vogl, Koichi Hatada

Emeritus Faculty Author Gallery

No abstract provided.


Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl Dec 2002

Personalities In Polymer Science: Cover Page, Title Page, Introduction, And List Of Articles, Otto Vogl

Emeritus Faculty Author Gallery

A compilation of articles with short biographies of the scientists who played leading roles in the field and provided the basis of Polymer Science and Technology throughout the 20th century.


Poly(Meta-Phenylene Isophthalamide) Nanofibers: Coating And Post Processing, Wenxia Liu, Mathew Graham, Edward A. Evans, Darrell Hyson Reneker Dec 2002

Poly(Meta-Phenylene Isophthalamide) Nanofibers: Coating And Post Processing, Wenxia Liu, Mathew Graham, Edward A. Evans, Darrell Hyson Reneker

College of Polymer Science and Polymer Engineering

Electrospun nanofibers have applications in the areas of filtration, composites; biomaterials, and electronics. Controlling the surface properties of these nanofibers is important for many applications. Nanofibers can also be used as unique substrates for observing the growth of deposited films and creating nanoscale structures. In this work, electrospun poly(meta-phenylene isophthalamide) (MPD-I) nanofibers were used as substrates for creating nanoscale structures out of carbon-based materials and metals. MPD-I was used because it can be electrospun into nanofibers with diameters smaller than 10 nm and it has good thermal stability. MPD-I nanofibers were coated with carbon, copper, and aluminum using plasma enhanced …


Acuta Enews December 2002, Vol 31, No. 12 Dec 2002

Acuta Enews December 2002, Vol 31, No. 12

ACUTA Newsletters

In This Issue

lmpact of Mobitity on Higher Education................ Jeanne Jansenius, Univ. of the South

Awareness: the First Step to Safety....................... Diane Santerelli, www.wireville.com

Tech Talk: Honeypot: Sweet Revenge Against Hackers?................... Kevin Tanzillo, Dux Public Relations

DC Update...................... Whitney Johnson, Retired, Northern Michigan Univ.

Donate-A-Phone Program

Download Movies

TEACH Act Signed lnto Law...................... Jeri Semer, CAE, Executive Director

Welcome New Members

Thanks to Our Sponsors


Ccr4-Bearing T Cells Participate In Autoimmune Diabetes., Soon H. Kim, Mary M. Cleary, Howard S. Fox, Icos Coporation, Nora Sarvetnick Dec 2002

Ccr4-Bearing T Cells Participate In Autoimmune Diabetes., Soon H. Kim, Mary M. Cleary, Howard S. Fox, Icos Coporation, Nora Sarvetnick

Journal Articles: Regenerative Medicine

Chemokine receptor expression is exquisitely regulated on T cell subsets during the course of their migration to inflammatory sites. In the present study we demonstrate that CCR4 expression marks a pathogenic population of autoimmune T cells. CCR4 was found exclusively on memory CD4(+) T cells during the progression of disease in NOD mice. Cells expressing the CCR4 ligand TARC (thymus- and activation-regulated chemokine) were detected within infiltrated islets from prediabetic mice. Interestingly, neutralization of macrophage-derived chemokine (MDC) with Ab caused a significant reduction of CCR4-positive T cells within the pancreatic infiltrates and inhibited the development of insulitis and diabetes. Furthermore, …


Why Benchmarking Is An (Asymptotically) Optimal Approach To Numerical Methods: A Geombinatoric Proof, Vladik Kreinovich, Scott A. Starks Dec 2002

Why Benchmarking Is An (Asymptotically) Optimal Approach To Numerical Methods: A Geombinatoric Proof, Vladik Kreinovich, Scott A. Starks

Departmental Technical Reports (CS)

In numerical mathematics, one of the most frequently used ways of gauging the quality of different numerical methods is benchmarking. Specifically, once we have methods that work well on some (but not all) problems from a given problem class, we find the problem that is the toughest for the existing methods. This problem becomes a benchmark for gauging how well different methods solve problems that previous methods could not. Once we have a method that works well in solving this benchmark problem, we repeat the process again -- by selecting, as a new benchmark, a problem that is the toughest …


31st Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences Dec 2002

31st Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences

Senior Engineering Design Conference

The 31st Conference on Senior Engineering Design Projects was held on December 3, 2002 at the College of Engineering and applied Sciences on the Parkview Campus of Western Michigan University. The college sponsors the conference to showcase the work of its graduating seniors, who are required to complete a capstone project that puts into practice what they have learned. Many of the projects are sponsored by business and industry.


Electrical Properties Of Srbi₂Ta₂O₉ Ferroelectric Thin Films At Low Temperature, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz Dec 2002

Electrical Properties Of Srbi₂Ta₂O₉ Ferroelectric Thin Films At Low Temperature, Pingxiong Yang, David L. Carroll, John Ballato, Robert W. Schwartz

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The temperature dependence of electrical properties for SrBi2Ta2O9 thin film capacitors with platinum electrodes (Pt/SBT/Pt) on silicon wafers was studied from 10 to 300 K. with a decrease in temperature from 300 to 200 K, the remanent polarization of the thin films shows about an 11% reduction from its 300 K value; however, it is reduced by about 87% reduction from its 200 K value when the temperature drops from 200 to 100 K. with a decrease to 200 K, the polarization fatigue was significant, and the capacitor shows an approximate 29% reduction in polarization from its initial value following …


2002 Statewide Bridge Sufficiency Rating Report, Indiana Ltap Dec 2002

2002 Statewide Bridge Sufficiency Rating Report, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

This report contains information specific to the county of interest, plus summary tables relating information about all Indiana county bridge conditions and funding levels.


Weibull Model Development For Fatigue Crack Growth, Bobby Day, Tarun Goswami Dec 2002

Weibull Model Development For Fatigue Crack Growth, Bobby Day, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

This effort is an attempt to "Weibullize" fatigue crack growth rate data as a function of stress intensity range (ΔΚ). It is not a classical Weibull application in that it does not address a population but rather treats rate of crack growth as a fraction of the highest rate of crack growth rate in the data set (usually the final data point of the set) as the "failed fraction of a population." All da/dN values are converted to a percentage or fraction of the 100% data value, processed into a linear relationship and plotted against the natural log of the …


A Review Of Nanotechnology Applications, Nick Ledbetter, Tarun Goswami Dec 2002

A Review Of Nanotechnology Applications, Nick Ledbetter, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

A review of current technology research efforts has been conducted in this paper. In nanoscience, objects are measured in nanometers, 1 billionth of a meter. For comparison, a human hair is approximately 100,000 nanometers thick and the smallest feature on current computer chips measures about 200 nanometers. Since nanotechnology has a wide range of applications from computer chip manufacturing, new materials, renewable energy, interconnection technology to mount the nano-chips, and in medical science, this review presents a broad summary of development efforts in the government and private sector laboratories. Therefore this project on the one hand prepares a review of …


Solar Dhw Collector Thermal Performance Ratings, Florida Solar Energy Center, John Harrison Dec 2002

Solar Dhw Collector Thermal Performance Ratings, Florida Solar Energy Center, John Harrison

FSEC Energy Research Center®

Thermal performance ratings, derived from the FSEC testing and certification program, are a useful tool in comparing the efficiency and economics of various flat-plate solar collectors. Since collectors used in domestic hot water (DHW) systems typically operate in the intermediate temperature range (1200F-1600F), this is the rating provided for comparisons. It must be stressed that these comparisons are only a guide and should not be considered as a rank ordering of collectors. Such considerations as component sizing and proper installation procedures are equally important in determining a system's overall efficiency. In addition, because of the variability of weather conditions, instrumentation …


Dynamic Yield Analysis And Enhancement Of Fpga Reconfigurable Memory Systems, Minsu Choi, Nohpill Park Dec 2002

Dynamic Yield Analysis And Enhancement Of Fpga Reconfigurable Memory Systems, Minsu Choi, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

This paper addresses the issues of field programmable gate arrays (FPGA) reconfigurable memory systems with faulty physical memory cells and proposes yield measurement techniques. Static yield (i.e., the yield which does not take into account the inherited redundancy utilization for repair) and dynamic yield (i.e., the yield which takes into account the inherited redundancy utilization for repair) of FPGA reconfigurable memory systems and their characteristics are extensively analyzed. Yield enhancement of conventional memory systems relies on additional redundancy, but FPGA reconfigurable memory systems have inherited redundancy and customizability. Thus, they can accommodate numerous target memory configurations, and redundant memory cells, …


Improving The Conceptual Understanding Of Kinematics Through Graphical Analysis, Glenn W. Ellis, Warren A. Turner Dec 2002

Improving The Conceptual Understanding Of Kinematics Through Graphical Analysis, Glenn W. Ellis, Warren A. Turner

Engineering: Faculty Publications

In this study, we use graphical analysis to develop a learner-centered approach to understanding kinematics. The learner-centered approach offers three advantages: it is consistent with pedagogy that has been shown to be effective for learning, it can be naturally integrated with real-time data collection using motion detectors or video analysis, and it provides a mechanism for developing insight into both physics and calculus. Students discover fundamental principles through a series of laboratory modules. The learning process is integrated into a conceptual framework through a variety of activities and application projects.


Survey Of Aviation Maintenance Technical Manuals, Phase 3 Report: Final Report And Recommendations, Alex Chaparro, Loren S. Groff Dec 2002

Survey Of Aviation Maintenance Technical Manuals, Phase 3 Report: Final Report And Recommendations, Alex Chaparro, Loren S. Groff

Publications

This report contains the results from the final phase of a three-phase research effort. Phase 1 of this research effort surveyed the procedures used by five aircraft manufacturers to develop maintenance documentation. Several potential human factors issues were identified in the processes used by these manufacturers to develop their maintenance manuals. The issues included the reactive rather than proactive use of user evaluations, the limited use of user input and procedure validation, no systematic attempts to track errors, and the lack of standards for measuring document quality. In Phase 2, a written survey was used to solicit information about user …


Auger Timing Effects On Performance Of A Combine Unloading System, Todd Philip Cole Dec 2002

Auger Timing Effects On Performance Of A Combine Unloading System, Todd Philip Cole

Open Access Master's Theses (through 2010)

Performance effects were measured on a combine unloading system using three different auger timing settings.Performance measures included maximum startup torque, mean operating torque, standard deviation of the operating torque, flow rate of grain through the system, and mechanical damage to the grain.The performance effects were measured with the system unloading corn and soybeans.

The data were statistically analyzed to check for interactions between the grains and differences between the timings.Using an alpha value of 0.1 it was found that timing 1 for both grains had a 3% (<2.4 L/s) higher flow rate over timings 2 and 3.Timings 1 and 2 for both grains had higher maximum startup torque, about 10% (60 N·m) more torque required than timing 3.In soybeans, timings 2 and 3 also had the smallest standard deviation in operating torque, about 30% (20 N·m) less than timing 1.We were unable to detect any differences in mechanical damage to corn or soybeans as a result of unloading auger timing.These findings suggest that timing 3, with the cross augers lagging 90° behind the vertical unloading auger, may require less maximum startup torque and less variation in torque for the cross augers to effectively fill the loosely filled space left after the vertical auger lifts the grain without extra torque effects of having the augers push against each other as they do in timing 1.

Advisor: Michael F. Kocher