Engineering Commons^™

Hysteresis And Anchoring Energy In Ferroelectric Liquid Crystals, Yuri Panarin

Articles

The frequency dispersion of the coercive force of Ferroelectric Liquid Crystals (FLC) cells has been detected and examined in the range of infralow (lower than 0.1 Hz) frequencies. To clarify the low-frequency dispersion, the model has been suggested, based on the arrangement of free charges and well describing the experimental curves. The method for determination of the energy of FLC anchoring at the surface, developed on the basis of the static hysteresis loop, has been proposed. The dependence of bistability and the anchoring energy upon the orientant layer thickness has experimentally been investigated.

Intel Nx To Pvm 3.2 Message Passing Conversion Library, Trey Arthur, Michael L. Nelson

Computer Science Faculty Publications

NASA Langley Research Center has developed a library that allows Intel NX message passing codes to be executed under the more popular and widely supported Parallel Virtual Machine (PVM) message passing library. PVM was developed at Oak Ridge National Labs and has become the defacto standard for message passing. This library will allow the many programs that were developed on the Intel iPSC/860 or Intel Paragon in a Single Program Multiple Data (SPMD) design to be ported to the numerous architectures that PVM (version 3.2) supports. Also, the library adds global operations capability to PVM. A familiarity with Intel NX …

A Comparison Of Queueing, Cluster And Distributed Computing Systems, Joseph A. Kaplan, Michael L. Nelson

Computer Science Faculty Publications

Using workstation clusters for distributed computing has become popular with the proliferation of inexpensive, powerful workstations. Workstation clusters offer both a cost effective alternative to batch processing and an easy entry into parallel computing. However, a number of workstations on a network does not constitute a cluster. Cluster management software is necessary to harness the collective computing power. A variety of cluster management and queuing systems are compared: Distributed Queueing Systems (DQS), Condor, Load Leveler, Load Balancer, Load Sharing Facility (LSF - formerly Utopia), Distributed Job Manager (DJM), Computing in Distributed Networked Environments (CODINE), and NQS/Exec. The systems differ in …

Observation Of The Charmed Baryon C+ And Measurement Of The Isospin Mass Splittings Of The C, Crawford, G.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.

Superheating Of Bi(0001), E. A. Murphy, H. E. Elsayed-Ali, J. W. Herman

Electrical & Computer Engineering Faculty Publications

Superheating of Bi(0001) by about 90 K above the bulk melting temperature is observed using time-resolved reflection high-energy electron diffraction with ∼200-ps time resolution. Larger temperature excursions above the bulk melting temperature result in melting accompanied by irreversible laser damage to the surface. The rhombohedral structure of Bi leads to very different behavior of material parameters upon melting as compared with fcc metals. Therefore, our observation of the superheating of Bi(0001), together with the previously observed superheating of Pb(111), suggests the generality of the superheating phenomenon.

Design And Implementation Of Fuzzy Logic Controllers. Thesis Final Report, 27 July 1992 - 1 January 1993, Osama A. Abihana, Oscar R. Gonzalez

Electrical & Computer Engineering Faculty Publications

The main objectives of our research are to present a self-contained overview of fuzzy sets and fuzzy logic, develop a methodology for control system design using fuzzy logic controllers, and to design and implement a fuzzy logic controller for a real system. We first present the fundamental concepts of fuzzy sets and fuzzy logic. Fuzzy sets and basic fuzzy operations are defined. In addition, for control systems, it is important to understand the concepts of linguistic values, term sets, fuzzy rule base, inference methods, and defuzzification methods. Second, we introduce a four-step fuzzy logic control system design procedure. The design …

Lattice Boltzmann Thermohydrodynamics, F. J. Alexander, S. Chen, J. D. Sterling

Business and Information Technology Faculty Research & Creative Works

We introduce a lattice Boltzmann computational scheme capable of modeling thermohydrodynamic flows of monatomic gases. The parallel nature of this approach provides a numerically efficient alternative to traditional methods of computational fluid dynamics. The scheme uses a small number of discrete velocity states and a linear, single-time relaxation collision operator. Numerical simulations in two dimensions agree well with exact solutions for adiabatic sound propagation and Couette flow with heat transfer. © 1993 The American Physical Society.

A Study Of Dynamic Optimization Techniques: Lessons And Directions In Kernel Design, Calton Pu, Jonathan Walpole

Computer Science Faculty Publications and Presentations

The Synthesis kernel [21,22,23,27,28] showed that dynamic code generation, software feedback, and fine-grain modular kernel organization are useful implementation techniques for improving the performance of operating system kernels. In addition, and perhaps more importantly, we discovered that there are strong interactions between the techniques. Hence, a careful and systematic combination of the techniques can be very powerful even though each one by itself may have serious limitations. By identifying these interactions we illustrate the problems of applying each technique in isolation to existing kernels. We also highlight the important common under-pinnings of the Synthesis experience and present our ideas on …

Chemical Structural Features Of Pyridine Extracts Of The Argonne Premium Coals Using 13c Nmr Spectroscopy, Thomas H. Fletcher, S Bai, Ronald J. Pugmire, Steven Wood, David M. Grant

Faculty Publications

Soxhlet extractions were performed on the eight Argonne Premium coals using pyridine purged with argon and followed by a novel washing procedure to remove the pyridine. Mass closure (extracts plus residues) on duplicate experiments accounted for 94-96% of the original coal, repeatable to within 2%. Chemical structural features determined from ¹³C NMR analyses of the extracts and residues showed more attachments per aromatic cluster for the residues, indicating a greater degree of covalent bonding in the residue than in the extract. ¹H NMR analysis of the extracts showed a gradual increase in the hydrogen aromaticity with rank, along …

Chemical Admixtures Of Highway Concrete: Fundamental Research And A Guide To Usage, Sidney Diamond, Keisuke Matsukawa

JTRP Technical Reports

No abstract provided.

Multiobjective Design Of Service Routes, J. R. Wright, Jin-Yuan Wang

JTRP Technical Reports

The purpose of this research has been the design of a computer-based decision support system for use in the design of service routes on the Indiana intrastate highway system. The following work has been completed for this purpose:

1) Acquisition of a 1:100,000 scale DLG data representation of the entire state transportation network.

2) Reclassification of those data with the aid of a computer-based interactive data filter and participation by DOT maintenance personnel from 6 districts.

3) Development of several route design algorithm components designed specifically for addressing the problem of routing snow and ice control vehicles for INDOT.

4) …

Subgrade Resilient Modulus For Pavement Design And Evaluation, Woojin Lee, Nihal Chand Bohra, A. G. Altschaeffl, Thomas D. White

JTRP Technical Reports

No abstract provided.

Strand Debonding In Pretensioned Beams - Precast Prestressed Concrete Bridge Girders With Debonded Strands - Continuity Issues, O. A. Abdalla, J. A. Ramirez, Robert H. Lee

JTRP Technical Reports

No abstract provided.

Debonding In Pretensioned Beams-Precast Strands, Part 2: Simply Supported Tests, O. A. Abdalla, J. A. Ramirez, Robert H. Lee

JTRP Technical Reports

No abstract provided.

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 …

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.

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 …

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; …

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 …

A Computational Algorithm For Squaring-Up, Part I: Zero Input-Output Matrix, Pradeep Misra

Electrical Engineering Faculty Publications

In this paper, some preliminary results on the problem of squaring-up a non-square linear multivariable system are presented. It. is shown that. for the case considered here. the squaring-up problem can be transformed into a state feedback problem. An illustrative numerical example is included to illustrate the results developed.

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 …

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.

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 …

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

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 …

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.

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. …

Project Smart: A Restoration/Demonstration, Martin Wanielista

BMP Trains Research and Publications

No abstract provided.

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 …