Engineering Commons^™

Nanosecond Transient Electroluminescene From Polymer Light-Emitting Diodes, David Braun, D. Moses, C. Zhang, A. J. Heeger

Electrical Engineering

The transient electroluminescence from polymer light-emitting diodes is reported. When the devices are mounted on a microstrip transmission line, the temporal response is limited by the electrode geometry, with rise and fall times below 50 ns. With low duty-cycle pulses (0.5%) the electroluminescence intensity remains proportional to the current at values up to 10 A/cm², two orders of magnitude greater than possible under direct current operation. Since the spectral blue-shift observed at high current levels (with power dissipation above 1 W/cm²) indicates significant sample heating, still higher levels should be possible with proper thermal management.

Thermally Activated Reversible Threshold Shifts In Yba2Cu3O7-Δ/Yttria-Stabilized Zirconia/Si Capacitors, Jianmin Qiao, Eric M. Ajimine, Paresh P. Patel, Geoffrey L. Giese, Cary Y. Yang

Electrical and Computer Engineering

Yba₂Cu₃O_7-δ/yttria‐stabilized zirconia (YSZ)/silicon superconductor–insulator–semiconductor capacitors are characterized with capacitance‐voltage (C‐V) measurements at different gate‐voltage sweep rates and under bias‐temperature cycling. It is shown that ionic conduction in YSZ causes both hysteresis and stretch‐out in room‐temperature C‐V curves. A thermally activated process with an activation energy of about 39 meV in YSZ and/or at YSZ/Si interface is attributed to trapping/detrapping mechanisms in the SiO_x interfacial layer between YSZ and Si. The negative mobile ions in YSZ can be moved by an applied electric field at room temperature and then ‘‘frozen’’ with decreasing temperature, giving …

Fuzzy Logic Applied To Adaptive Kalman Filtering, Marlys Rae Remus

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The Kalman filter provides an effective means of estimating the state of a system from noisy measurements given that the system parameters are completely specified. The innovations sequence for a properly specified Kalman filter will be a zero-mean white noise process. However, when the system parameters change with time the Kalman filter will need to be adapted to compensate for the changes. Traditionally this has been accomplished by using nonlinear filtering, parallel Kalman filtering and covariance matching techniques. These methods have produced good results at the expense of large amounts of computational time. Necessary changes in the system parameters become …

High-Level Expression Of A Heterologous Protein In The Milk Of Transgenic Swine Using The Cdna Encoding Human Protein C, William H. Velander, John L. Johnson, Raymond L. Page, Christopher G. Russell, Anuradha Subramanian, Tracy D. Wilkins, Francis C. Gwazdauskas, Christoph Pittius, William N. Drohan

William H. Velander Publications

Transgenic pigs were generated that produced human protein C in their milk at up to 1 g/liter. The gene construct was a fusion gene consisting of the cDNA for human protein C inserted into the first exon of the mouse whey acidic protein gene. These results demonstrate that the mouse whey acidic protein gene contains regulatory elements that can direct cDNA expression at high levels in the pig mammary gland. Recombinant human protein C that was produced at about 380 pg/ml per hr in transgenic pig milk possessed anticoagulant activity that was equivalent to that of protein C derived from …

Method Of Predicting Cut-Time Of Milk Coagulum In Cheese-Making Process, Frederick A. Payne, Clair L. Hicks

Biosystems and Agricultural Engineering Faculty Patents

An apparatus for predicting milk coagulum cut-time in a cheese making process includes a light source, a sensor or detector for sensing diffuse reflectance of light from said milk and a controller for analyzing the diffuse reflectance and accurately predicting the cut-time to significantly enhance overall yield. More specifically, the apparatus includes an optical probe which may be suspended over the milk or attached to a wall of a fermentation vessel in which the milk is contained. A method for predicting milk coagulum cut-time includes the steps of (a) directing light from a light source toward milk undergoing enzymatic hydrolysis; …

The Implementation Of Photovoltaic Transportation Devices, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) and the Florida Department of Transportation (FDOT) are currently involved in a program to implement solar electric (photovoltaic) powered applications in the transportation sector. The objective of the program is to encourage the widespread use of cost-effective, transportation related, photovoltaic-powered systems in all areas of traffic control.

Transportation departments have generally relied on conventional practices of using generators, primary batteries, and extensions of utility grid to fulfil their power needs. There exist many remote and conventional electric power requirements within the FDOT that may be effectively satisfied by photovoltaic (PV) power. Applications ranging from …

An Investigation Of Performance Appraisal With Recommendations For White Collar And Blue Collar Workers, Mark W. Alberts

Graduate Research Papers

The accurate evaluation of an employee's performance, whether it be a salary or wage worker, is one of the most challenging problems confronting any organization. According to Lazer (1977), which is still true today, performance appraisal is absolutely necessary if an organization is to prosper in the highly competitive world of modern business.

Regardless of all that has been written about the how and why of performance appraisal, there still seems to be constant problems and areas of clear disagreement. Published writings about performance appraisal cover approximately the past 30 years and deal mostly with private corporations. Before that, performance …

Active Vibration Control Device, Keith E. Rouch, Sanjiv Tewani, Bruce L. Walcott, Ted R. Massa, Robert W. Stephenson, L. Scott Stephens

Mechanical Engineering Faculty Patents

An active vibration control device for controlling vibration in a cantilevered member and a method for the same are disclosed. The device is comprised of a cantilevered member having a longitudinal axis comprising a sensor mounted near the free end of the member to measure motion of the member in a transverse direction and to produce a corresponding signal. A force generating assembly is mounted to the member near the free end to oppose the measured motion with a force thereby minimizing subsequent motion along the transverse axis caused by vibration.

Royal Institute Of Technology: Department Of Polymer Technology, Otto Vogl, Ann Christine Albertsson

Emeritus Faculty Author Gallery

No abstract provided.

70. Obituary, Herman F. Mark, Otto Vogl

Emeritus Faculty Author Gallery

No abstract provided.

Project Smart: A Restoration/Demonstration, Martin Wanielista

BMP Trains Research and Publications

No abstract provided.

10th Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences

Senior Engineering Design Conference

The 10th Conference on Senior Engineering Design Projects was held on December 8, 1992 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.

Acuta Enews December 1992, Vol. 21, No. 12

ACUTA Newsletters

In This Issue

Regulatory update

President's column

Dual routing protects Duke

Talking clock "tells" time

Seminar ratings

Director's column

Losses In Electric Power Systems, E. Benedict, T. Collins, D. Gotham, S. Hoffman, D. Karipides, S. Pekarek, R. Ramabhadran

Department of Electrical and Computer Engineering Technical Reports

This report concerns losses in power systems. The report was assembled by seven authors in EE 532 class at Purdue University in December, 1992. The work was part of a class project on losses . All aspects of losses are discussed from the transmission system through utilization stages. High efficiency motors and lighting are also considered . The students participating in this project also videotaped presentations on power system losses .

Guide To Revenue Calculations: Local Option Highway User Tax 1992, Jon D. Fricker

Indiana Local Technical Assistance Program (LTAP) Publications

This guide is provided to explain the output generated by the computer programs, and to suggest ways in which the results can be adapted to specific LOHUT proposals before a County Council. HERPICC neither endorses nor opposes passage of a LOHUT. The revenue projections it provides are intended to be an aid to well-informed decision-making on the part of a county’s citizens and its County Council.

Rebuilding For Efficiency: Improving The Energy Use Of Reconstructed Residences In South Florida, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

On August 24th, 1992, Hurricane Andrew devastated a large part of South Dade County in Florida. With over 35,000 homes to be rebuilt, there is interest in seeing if these reconstructed residences can be made more energy-efficient.

This report provides a comprehensive assessment of potential energy efficiency improvements for both new and existing homes in South Florida. Over forty energy-efficiency measures were considered in the analysis. Many homes in the effected zone experienced damage to their windows, roofs and the surrounding landscape. As a result, the analysis closely examined options associated with these design aspects. All major end-uses of electricity …

Design Of Automotive Structural Components Using High Strength Sheet Steels Influence Of Strain Rate On The Mechanical Properties Of Sheet Steels And Structural Performance Of Cold-Formed Steel Members, Chi-Ling Pan, Wei-Wen Yu

CCFSS Library (1939 - present)

The current design criteria for effective design width being used in the AISI Automotive Steel Design Manual 1 for the design of cold-formed steel members are based on tests under static loading condition. The primary objective of this investigation was to study the validity of these effective design width formulas for members subjected to dynamic loads. This report presents a detailed description of an experimental study. Selected steels with nominal yield strengths ranging from 25 ksi to 100 ksi were uniaxially tested under different strain rates. In order to study the structural behavior and strength of cold-formed steel members having …

Viscosities Of Vegetable Oils And Fatty Acids, Hossein Noureddini, B C. Teoh, L Davis Clements

Papers in Biomaterials

Data for viscosity as a function of temperature from 24 to llO°C (75 to 230°F) have been measured for a number of vegetable oils (crambe, rapeseed, corn, soybean, milk- coconut, lesquerella) and eight fatty acids in the from Cg to CZZ The viscosity measurements were performed according to ASTM test methods D 445 and D 446. Several correlations were fitted to the experimental data. Correlation constants for the best fit are presented. The range of temperature in which the correlations are valid is from 24'C (75'F), or the melting point of the substance, to llO°C (230°F). The correlation constants are …

Densities Of Vegetable Oils And Fatty Acids, Hossein Noureddini, B C. Teoh, L Davis Clements

Papers in Biomaterials

Complete data for density as a function of temperature have been measured for a number of vegetable oils (cramhe, rapeseed, corn, soybean, milkweed, coconut, lesquerella), as well as eight fatty acids in the range CS to C,, at temperatures from above their melting points to llQ°C (23Q°F). The specific gravity and density measure mente were performed according to American Society for Testing and Materials (ASTM) standard test methods D 368, D 891 and D 1298 for hydrometers and a modified ASTM D 369 and D 891 for pycnometers. Correlation constants, based on the experimental data, are presented for calculating the …

High-Level Expression Of A Heterologous Protein In The Milk Of Transgenic Swine Using The Cdna Encoding Human Protein C, William H. Velander, John L. Johnson, Raymond L. Page, Chritopher G. Russell, Anuradha Subramanian, Tracy D. Wilkins, Francis C. Gwazdauskas, Christoph Pittus, William N. Drohan

Papers in Biotechnology

Transgenic pigs were generated that produced human protein C in their milk at up to 1 g/liter. The gene construct was a fusion gene consisting of the cDNA for human protein C inserted into the first exon of the mouse whey acidic protein gene. These results demonstrate that the mouse whey acidic protein gene contains regulatory elements that can direct cDNA expression at high levels in the pig mammary gland. Recombinant human protein C that was produced at about 380 pg/ml per hr in transgenic pig milk possessed anticoagulant activity that was equivalent to that of protein C derived from …

Photopolymer-Based Stratified Volume Holographic Optical Elements, Gregory P. Nordin, A. R. Tanguay

Faculty Publications

We report the implementation of stratified volume holographic optical elements (SVHOE's) using DuPont's Omnidex holographic photopolymer material and an in situ exposure technique for simultaneous multilayer grating recording. Experimental measurement of the +1-order angular sensitivity of a seven-layer SVHOE structure shows remarkable agreement with both theory and numerical simulation for incidence angles near the Bragg angle. For SVHOE's having modulation layers that individually operate in the Bragg or transition diffraction regimes, the envelope of the SVHOE angular sensitivity is experimentally shown to approximate closely that of a single modulation layer.

An Efficient Technique For Finding The Desired Global Optimum Of Robotic Joint Displacement, Paul P. Lin, An-Jen J. Yang

Mechanical Engineering Faculty Publications

For an industrial robot on a daily operation basis such as pick and place, it is desired to minimize the robotic joint displacements when moving the robot from one location to another. The objective of the optimization here is to simultaneously minimize a robot end effector's positional error and the robotic joint displacements. By modifying the searching algorithm in the existing complex optimization method, this article presents a technique for finding the desired global optimum solution more efficiently. To compare the optimum searching capability between the proposed and existing searching algorithms, a modified Himmelblau's function is used as an objective …

Laminar/Turbulent Oscillating Flow In Circular Pipes, Kyung H. Ahn, Mounir B. Ibrahim

Mechanical Engineering Faculty Publications

A two-dimensional oscillating flow analysis was conducted simulating the gas flow inside Stirling engine heat exchangers. Both laminar and turbulent oscillating pipe flow were investigated numerically for Re_max = 1,920 (Va = 80), 10,800 (Va = 272), 19,300 (Va = 272), and 60,800 (Va = 126). The results are here compared with experimental results of previous investigators. Predictions of the flow regime on present oscillating flow conditions are also checked by comparing velocity amplitudes and phase difference with those from laminar theory and quasi-steady profile. A high Reynolds number k-ε turbulence model was used for turbulent oscillating pipe flow. …

Efficient Accommodation Of May-Alias Information In Ssa Form, Ron Cytron, Reid Gershbein

All Computer Science and Engineering Research

We present an algorithm for incrementally including may-alias information into Static Single Assignment form by computing a sequence of increasingly precise (and correspondingly larger) partial SSA forms. Our experiments show significant speedup of our method over exhaustive use of may-alias information, as optimization problems converge well before most may-aliases are needed.

Exact Dominance Without Search In Decision Trees, Nilesh L. Jain, Ronald P. Loui

All Computer Science and Engineering Research

In order to improve understanding of how planning and decision analysis relate, we propose a hybrid model containing concepts from both. This model is comparable to [Hartman90], with slightly more detail. Dominance is simple concept in decision theory. In a restricted version of our model, we give conditions under which dominance can be detected without search: that is, it can be used as a pruning strategy to avoid growing large trees. This investigation follows the lead of [Wellman87]. The conditions seem hard to meet, but may nevertheless be useful in forward-chaining situations without focus, such as [Breese87]. It may be …

Diffraction Properties Of Stratified Volume Holographic Optical Elements, Gregory P. Nordin, R. V. Johnson, A. R. Tanguay

Faculty Publications

We present a unified treatment of the diffraction properties of stratified volume holographic optical elements (SVHOE's). We show that the relative phasing of the diffraction orders as they propagate from layer to layer gives rise to a unique notched diffraction response of the +1 order (for the case of Bragg incidence) as a function of the normalized buffer-layer thickness, the grating spatial frequency, and the readout wavelength. For certain combinations of these parameters Bragg diffraction behavior characteristic of volume holographic optical elements (VHOE's) is observed, whereas for other combinations pure Raman-Nath behavior periodically recurs. By using these same relative-phasing arguments, …

Hands-On Structural Engineering Experiences With The "Anex" Mini-Laboratory, Richard A. Behr, Colin Othniel Benjamin, Azam A. Mirza

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The ANEX facility has been developed to allow nearly real-time comparisons of analysis results with experimental data gathered on small-scale structural models. ANEX has been used successfully for in-class demonstrations, student-designed experiments, and comprehensive design/build competitions in an introductory structural analysis course at the University of Missouri-Rolla. An expert system is now being developed to guide ANEX users and to act as a trouble-shooter and advisor in the event that analytical and experimental results do not correlate acceptably well. ANEX, using only simple, small-scale model structures, is able to enrich structural engineering instruction by introducing students to the sophisticated capabilities …

Sediment Delivery On Rill And Interrill Areas, John E. Gilley, D. C. Kincaid, W. J. Elliot, J. M. Laflen

Biological Systems Engineering: Papers and Publications

Equations which relate sediment delivery to a power function of flow rate and slope gradient were calculated in this study. The data used to parameterize the calculations were obtained from sites where crop residues had been removed. and moldboard plowing and disking had occurred. Measurements of sediment delivery resulting from simulated rainfall were obtained from preformed rills and interrill areas. The equations provided reliable sediment delivery estimates for selected soils located throughout the United States. To use the sediment delivery equations, soil-related parameter values must be identified. Multiple regression analyses were performed to relate parameter values used in the equations …

On The Difficulty Of Manhattan Channel Routing, Ronald I. Greenberg, Joseph Jaja, Sridhar Krishnamurthy

Computer Science: Faculty Publications and Other Works

We show that channel routing in the Manhattan model remains difficult even when all nets are single-sided. Given a set of n single-sided nets, we consider the problem of determining the minimum number of tracks required to obtain a dogleg-free routing. In addition to showing that the decision version of the problem isNP-complete, we show that there are problems requiring at least d+Omega(sqrt(n)) tracks, where d is the density. This existential lower bound does not follow from any of the known lower bounds in the literature.

Oxidative Mechanisms In Arterial Distension Injury: Observations Relevant To Restenosis After Angioplasty, Charles F. Babbs, Yuan Zhong

Weldon School of Biomedical Engineering Faculty Working Papers

Background: To explore the hypothesis that tissue iron and reactive oxygen species, including superoxide (O2), mediate acute inflammatory and late hyperplastic responses to vascular injury, we studied experimental overdistension of normal carotid and femoral arteries in dogs. Experimental design: Arterial segments isolated in situ were distended with Ringer solution at 2 atmospheres pressure. In initial experiments the arteries were excised immediately after distension and immersed in diaminobenzidine solutions containing Mn++ ions to initiate histochemical reactions for O2. In other experiments distended arterial segments were reperfused with arterial blood in the presence or absence of the iron chelator, deferoxamine, or the …