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1998

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Analysis Of The Value Of The Fe Examination For The Assessment Of Student Learning In Engineering And Science Topics, John L. Watson Jan 1998

Analysis Of The Value Of The Fe Examination For The Assessment Of Student Learning In Engineering And Science Topics, John L. Watson

Materials Science and Engineering Faculty Research & Creative Works

This paper presents the results of a project, which investigated the potential of fully using previously unreleased data from the nationally normed Fundamentals of Engineering (FE) examination to assess learning in key engineering and science topics. In the past, very limited information was released by the National Council of Examiners for Engineers and Surveyors (NCEES) for the eight hour FE examination, which is composed of 150-200 questions in ten morning and five afternoon topics. For the purposes of this project the NCEES agreed to release information to the University of Missouri-Rolla (UMR) to permit the value of the FE data …


Electrodeposition Of Copper On Thermally Oxidized 316 L Stainless Steel Substrates, Z. Zhou, Thomas J. O'Keefe Jan 1998

Electrodeposition Of Copper On Thermally Oxidized 316 L Stainless Steel Substrates, Z. Zhou, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

The effect of thermal oxidation of 316 L stainless steel cathode blanks used in copper electrodeposition was studied. Current and potential step experiments were performed to evaluate electrochemical changes caused by the oxidation treatments. SEM and AES were used to characterize the stainless-steel substrates and the deposited copper films. Particular emphasis was given to the initial stages of copper nucleation and growth. The copper electro crystallization process was strongly influenced by the temperature employed in oxidizing the stainless steel. Dense, uniform and fine copper nuclei were obtained on the stainless-steel substrate oxidized in air at 200°C and 300°C for 3 …


Organically Deposited Metallic Films For Device Fabrication, Thomas J. O'Keefe, M. Stroder, Matthew O'Keefe Jan 1998

Organically Deposited Metallic Films For Device Fabrication, Thomas J. O'Keefe, M. Stroder, Matthew O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

Advances in integrated circuit density, speed and complexity are dependent on lower resistance, finer line width on-chip interconnections. Methods for incorporating copper interconnects into IC fabrication processes have been developed which accomplish this objective but most of these methods use some form of blanket metal deposition that requires mechanical and/or chemical removal of excess material. To date, investigations into the selective deposition of conductor materials for device fabrication have met with limited success. A new process for selectively depositing metallic conductors using inexpensive, organic-based chemical solutions could potentially force a paradigm shift in the deposition of metals for microelectronic applications. …


Magnetic And Thermal Properties Of Pr In La₁₋ₓprxbacacu₃O₇ System With 0.0, Rajvir Singh, S. Uma, E. Gmelin, William B. Yelon, V. P. S. Awana, S. X. Dou, A. V. Narlikar, Satish K. Malik Jan 1998

Magnetic And Thermal Properties Of Pr In La₁₋ₓprxbacacu₃O₇ System With 0.0, Rajvir Singh, S. Uma, E. Gmelin, William B. Yelon, V. P. S. Awana, S. X. Dou, A. V. Narlikar, Satish K. Malik

Physics Faculty Research & Creative Works

No abstract provided.


Pressure Induced Reversal Of The Volume Expansion Caused By Interstitial Nitrogen In Nd₂Fe₁₇N₃, R. Luo, William B. Yelon, Yusheng S.. Zhao, M. Ellouze, Ph. I'Héritier, G. K. Marasinghe, Peter C. Ezekwenna, R. B. Von Dreele, William Joseph James Jan 1998

Pressure Induced Reversal Of The Volume Expansion Caused By Interstitial Nitrogen In Nd₂Fe₁₇N₃, R. Luo, William B. Yelon, Yusheng S.. Zhao, M. Ellouze, Ph. I'Héritier, G. K. Marasinghe, Peter C. Ezekwenna, R. B. Von Dreele, William Joseph James

Physics Faculty Research & Creative Works

No abstract provided.


Graduate Recital In Voice, Paul Huber Jan 1998

Graduate Recital In Voice, Paul Huber

Dissertations and Theses @ UNI

In partial fulfillment of the Master of Music degree requirements for performance, I performed a recital on Monday, October 26, 1998, in the Russell Hall Auditorium at the University of Northern Iowa. The recital consisted of three art songs by Gaetano Donizetti, a selection of art songs from Franz Schubert's Schwanengesang, Samuel Barber's Dover Beach, and Maurice Ravel's Don Quichotte á Dulcinee.


A Transaction Model For Mobile Computing, Sanjay Kumar Madria, Bharat Bhargava Jan 1998

A Transaction Model For Mobile Computing, Sanjay Kumar Madria, Bharat Bhargava

Computer Science Faculty Research & Creative Works

We introduce a prewrite operation before a write operation in a mobile transaction to improve data availability. A prewrite operation does not update the state of a data object but only makes visible the value that the data object will have after the commit of the transaction. Once the transaction has read all the values and declares all the prewrites, it can precommit at a mobile host. The remaining transaction's execution is shifted to the stationary host. Writes on a database consume both time and resources at the stationary host and are therefore delayed. A pre-committed transaction's prewrite values are …


A Transmission-Constrained Unit Commitment Method, Chung-Li Tseng, Chao-An Li, S. S. Oren, C. S. Cheng, A. J. Svoboda, R. B. Johnson Jan 1998

A Transmission-Constrained Unit Commitment Method, Chung-Li Tseng, Chao-An Li, S. S. Oren, C. S. Cheng, A. J. Svoboda, R. B. Johnson

Engineering Management and Systems Engineering Faculty Research & Creative Works

The paper presents a transmission-constrained unit commitment method using a Lagrangian relaxation approach. The transmission constraints are modeled as linear constraints based on a DC power flow model. The transmission constraints, as well as the demand and spinning reserve constraints, are relaxed by attaching Lagrange multipliers. The authors take a new approach in the algorithmic scheme. A three-phase algorithm is devised including dual optimization, a feasibility phase and unit decommitment. A test problem involving more than 2500 transmission lines and 2200 buses is tested along with other test problems


Systolic Algorithm For Processing Rle Images, Hao Feng, Fikret Erçal, Filiz Bunyak Jan 1998

Systolic Algorithm For Processing Rle Images, Hao Feng, Fikret Erçal, Filiz Bunyak

Computer Science Faculty Research & Creative Works

Image difference operation is commonly used in on-line automated printed circuit board (PCB) inspection systems as well as many other image processing applications. In this paper, we describe a new systolic algorithm and its system architecture which computes image differences in run-length encoded (RLE) format. The efficiency of this operation greatly affects the overall performance of the inspection system. It is shown that, for images with a high similarity measure, the time complexity of the systolic algorithm is a small constant. A formal proof of correctness for the algorithm is also given in the paper.


Optical Digital Fragmentation Measuring Systems -- Inherent Sources Of Error, Norbert H. Maerz, Wei Zhou Jan 1998

Optical Digital Fragmentation Measuring Systems -- Inherent Sources Of Error, Norbert H. Maerz, Wei Zhou

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Automated optical imaging systems of measuring fragmentation are increasingly being used in the mining, comminution, and materials handling industries. These methods have been well received in many of the industries involved. Considering that in many of these applications there are no alternative ways of sizing material, having even a rudimentary measurement of size distributions allows evaluations of explosive, blast design, detonator performance, crusher and milling performance, and material degradation due to transport.

Optical methods have inherent limitations, which reflect on accuracy, precision, and reproducibility of measurement results. This stems from the fact that there are myriads of variables, which affect …


A Practical Continually Online Trained Artificial Neural Network Controller For A Turbogenerator, Ganesh K. Venayagamoorthy, Ronald G. Harley Jan 1998

A Practical Continually Online Trained Artificial Neural Network Controller For A Turbogenerator, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper reports on the simulation and practical studies carried out on a single turbogenerator connected to an infinite bus through a short transmission line, with a continually online trained (COT) artificial neural network (ANN) controller to identify the turbogenerator, and another COT ANN to control the turbogenerator. This identifier/controller augments/replaces the automatic voltage regulator and the turbine governor. Results are presented to show that this COT ANN identifier/controller has the potential to allow turbogenerators to operate more closely to their steady-state stability limits and nevertheless “ride through” severe transient disturbances such as three phase faults. This allows greater usage …


An Efficient, Fast Converging Adaptive Filter For Network Echo Cancellation, Steven L. Grant Jan 1998

An Efficient, Fast Converging Adaptive Filter For Network Echo Cancellation, Steven L. Grant

Electrical and Computer Engineering Faculty Research & Creative Works

This paper discusses a fast efficient adaptive filtering algorithm for network echo cancellers PNLMS++ (proportionate normalized least mean squares ++). Compared to the conventional normalized least mean squares (NLMS) algorithm, PNLMSI++ converges much more quickly when the echo path is sparse. When the echo path is dispersive, the convergence rate is the same as NLMS. In addition, the new algorithm diverges at the same rate and to the same misalignment level as NLMS during periods of undetected double-talk. PNLMS++ is only 50% more computationally complex than NLMS and requires no additional memory


Segmentation Of Printed Circuit Board Images Into Basic Patterns, Madhav Moganti, Fikret Ercal Jan 1998

Segmentation Of Printed Circuit Board Images Into Basic Patterns, Madhav Moganti, Fikret Ercal

Computer Science Faculty Research & Creative Works

Segmentation is the first and foremost step in the inspection of the printed circuit boards. In this paper a new technique for the segmentation of printed circuit board (PCB) images is presented. The technique basically segments a given PCB into small windows containing primitive PCB subpatterns. The technique proposed exploits the simplicity and the homogeneity of the PCB images and is inherently parallel. A detailed discussion of the experiments and the results obtained is also presented. © 1993 Academic Press.


Investigation Of A Complex Reaction Network: I. Experiments In A High-Pressure Trickle-Bed Reactor, M. R. Khadilkar, Y. Jiang, M. (Muthanna) H. Al-Dahhan, M. P. Duduković, S. K. Chou, G. Ahmed, R. Kahney Jan 1998

Investigation Of A Complex Reaction Network: I. Experiments In A High-Pressure Trickle-Bed Reactor, M. R. Khadilkar, Y. Jiang, M. (Muthanna) H. Al-Dahhan, M. P. Duduković, S. K. Chou, G. Ahmed, R. Kahney

Chemical and Biochemical Engineering Faculty Research & Creative Works

A High-Pressure Trickle-Bed Reactor Was Used to Achieve High Productivity and Selectivity for the Manufacture of a Key Herbicide Intermediate (Α-Aminomethyl-2-Furanmethanol (Amino Alcohol, AA) from Α-Nitromethyl-2-Furanmethanol (Nitro Alcohol, NA). Raney Nickel Catalysts of Varying Activity Were Prescreened for Suitability in Trickle-Bed Operation. the Effect of Operating Parameters Such as Reactant Feed Concentration, Liquid Mass Velocity, and Temperature on the Yield of Amino Alcohol (AA) for RNi-A Are Discussed. the Superiority of Trickle-Bed Reactors over Others Such as Semibatch and Batch Slurry Systems is Demonstrated. the AA Yield Increases with Decrease in Feed Reactant Concentration and Liquid Mass Velocity, as Well …


Prediction Of Pressure Drop And Liquid Holdup In High-Pressure Trickle-Bed Reactors, M. (Muthanna) H. Al-Dahhan, M. R. Khadilkar, Y. Wu, M. P. Duduković Jan 1998

Prediction Of Pressure Drop And Liquid Holdup In High-Pressure Trickle-Bed Reactors, M. (Muthanna) H. Al-Dahhan, M. R. Khadilkar, Y. Wu, M. P. Duduković

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Holub Et Al. (1992, 1993) Phenomenological Model for Pressure Drop and Liquid Holdup in Trickle Flow Regime at Atmospheric Pressure Was Noted by Al-Dahhan and Duduković (1994) to Systematically Underpredict Pressure Drop at High Pressure and High Gas Flow Rates. in This Study, the Holub Et Al. (1992, 1993) Model Has Been Extended to Account for the Interaction between the Gas and Liquid Phases by Incorporating the Velocity and the Shear Slip Factors between the Phases. as a Result, the Prediction of Pressure Drop at the Operating Conditions of Industrial Interest (High Pressure) Has Been Improved Noticeably Without Any …


An Interlibrary Loan System On The World Wide Web, Schubert Shou Boon Foo, Ee Peng Lim Jan 1998

An Interlibrary Loan System On The World Wide Web, Schubert Shou Boon Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Inter-Library Loan (ILL) service is one of the services provided by libraries that offers users a way to access library resources beyond their affiliated libraries. Additionally, it allows participating libraries to share and maximize their resources. This work examines the ILL process used by libraries in Singapore and proposes that the existing paper-based manual system be replaced by a Web-based ILL system. Such a Web-based system has been successfully designed and implemented at the Nanyang Technological University. The paper presents an overview of the system requirements and architecture, implementation details and demonstrates the feasibility and advantages of the new system.


An Integrated Web-Based Ill System For Singapore Libraries, Schubert Foo, Ee Peng Lim Jan 1998

An Integrated Web-Based Ill System For Singapore Libraries, Schubert Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The paper proposes an integrated Web-based inter-library loan (ILL) system to replace and enhance the existing manual-based ILL system used by Singapore libraries. It describes the system requirements that must be supported in order to make it a viable and acceptable solution to all participating libraries. Subsequently, it presents the client-server Web-based system architecture, database design and Java development platform that are used to implement the system. The new system exhibits a host of advantages over the manual system including the minimising of human resource by eliminating form-filling and other forms of paper work completely, improving the access and speed …


A-Train: Memoirs Of A Tuskegee Airman, By Lt. Col. Charles W. Dryden, Steven D. Smith Jan 1998

A-Train: Memoirs Of A Tuskegee Airman, By Lt. Col. Charles W. Dryden, Steven D. Smith

Faculty Publications

A review of A-Train: Memoirs of a Tuskegee Airman, by Lt C. Charles W. Dryden.


Experimental Measurements And Simulation Of Mixing And Chemical Reaction In A Stirred Tank, Robertp Zipp, Gary Kent Patterson Jan 1998

Experimental Measurements And Simulation Of Mixing And Chemical Reaction In A Stirred Tank, Robertp Zipp, Gary Kent Patterson

Chemical and Biochemical Engineering Faculty Research & Creative Works

Effects of mixing on the rate of second-order chemical reactions have been studied by measuring the time-average degree of conversion at enough points in a steady-state, continuous-flow stirred reactor to provide comparisons with numerical simulations of the same reactions using a standard Reynolds-averaged turbulence simulation code with an added closure. The reactants were introduced in widely separated feed streams in order to provide a difficult test for the measurements and simulations. Concentration and segregation measurements were made with two fluorescence based methods - one remote and one using a fiber optic probe. The rates of mixing and reaction were simulated …


Java, Java, Java, Chaman Sabharwal Jan 1998

Java, Java, Java, Chaman Sabharwal

Computer Science Faculty Research & Creative Works

Everyone is talking about Java. The driving force for this chatter is Java''s simplicity and potential power. Java is programming language, and a language for the intranet and the World Wide Web (WWW). Java is a Write On one platform and Run on Many platforms (WORM) language. For network-friendly, platform-independent applications, Java (originally Oak) is an object oriented programming language. Java source code is compiled into a virtual machine code or bytecode. This makes the Java platform independent. It can be placed on a Web site, and executed on the client side on a PC-Intel, Mac, Motorola or UNIX-Solaris machine …


On-Line Team Project Communication Tool Set, Halvard E. Nystrom, D. R. Risco Jan 1998

On-Line Team Project Communication Tool Set, Halvard E. Nystrom, D. R. Risco

Engineering Management and Systems Engineering Faculty Research & Creative Works

Team projects offer a valuable mechanism for effective learning. However, communication within the team, with the instructor and between different teams is a challenging task that can greatly limit the effectiveness of the learning experience. Some of the tools and concepts that are being developed for distance learning applications can be used to enhance team project communication within teams that are geographically separated as well as for in-campus teams. This article documents a set of on-line tools that allow for asynchronous team participation and timely monitoring and feedback by the instructor.


A Neutron Diffraction Structural Study Of R₂Fe₁₇₋ₓalx(C) (R=Tb,Ho) Alloys, William B. Yelon, H. Luo, Mingxing Chen, W. C. Chang, S. H. Tsai Jan 1998

A Neutron Diffraction Structural Study Of R₂Fe₁₇₋ₓalx(C) (R=Tb,Ho) Alloys, William B. Yelon, H. Luo, Mingxing Chen, W. C. Chang, S. H. Tsai

Physics Faculty Research & Creative Works

No abstract provided.


Neutron Diffraction And Frequency Dependence Of The A.C. Susceptibility Of The System Zncr₂Xal₂-₂Xs₄, M. Hamedoun, A. Hourmatallah, N. Benzakour, K. Mediouri, J. Ilali, William B. Yelon, H. Luo Jan 1998

Neutron Diffraction And Frequency Dependence Of The A.C. Susceptibility Of The System Zncr₂Xal₂-₂Xs₄, M. Hamedoun, A. Hourmatallah, N. Benzakour, K. Mediouri, J. Ilali, William B. Yelon, H. Luo

Physics Faculty Research & Creative Works

No abstract provided.


Excitation Of The Whispering-Gallery-Modes At The Shielded Hemispherical Dielectric Resonator, Sergey Kharkovsky, V. V. Kutuzov, A. E. Kogut, V. A. Solodovnik Jan 1998

Excitation Of The Whispering-Gallery-Modes At The Shielded Hemispherical Dielectric Resonator, Sergey Kharkovsky, V. V. Kutuzov, A. E. Kogut, V. A. Solodovnik

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.


Microwave Filtering Of Unwanted Oscillations On Base Of Hexagonal Ferrite Composite Thick Films, Marina Koledintseva, Alexander A. Kitaytsev, Andrey A. Shinkov Jan 1998

Microwave Filtering Of Unwanted Oscillations On Base Of Hexagonal Ferrite Composite Thick Films, Marina Koledintseva, Alexander A. Kitaytsev, Andrey A. Shinkov

Electrical and Computer Engineering Faculty Research & Creative Works

The paper is aimed at the design of waveguide filters of lower frequencies using composite thick films (CTF) made of high-anisotropy polycrystalline hexagonal ferrite powders. Theoretical and experimental results describing the possibility of forming the desired frequency characteristic of the filters are presented


Millimeter Wave Signals Detection By Means Of Monocrystal Hexagonal Ferrite Ellipsoid, Marina Koledintseva, Alexander A. Kitaytsev Jan 1998

Millimeter Wave Signals Detection By Means Of Monocrystal Hexagonal Ferrite Ellipsoid, Marina Koledintseva, Alexander A. Kitaytsev

Electrical and Computer Engineering Faculty Research & Creative Works

Stable nonlinear resonance effects (SNLREs) have been already studied in crystallographically "isotropic" ferrogarnet ferrite resonators (FR), employed as microwave detectors in the frequency range of 300 MHz to 30 GHz. Application of prospective hexagonal monocrystal ferrites with large field of crystallographic magnetic anisotropy leads to the possibility of a gyromagnetic converter (GC) design for mm waveband (from 30 to 200 GHz) without massive external magnets. This paper deals with the analysis of a more general case with taking into account both crystallographic and form anisotropy as well as the arbitrary orientation of the main crystallographic axis with respect to the …


Deuterium Nmr Of Adsorbed Poly(Methyl Acrylate)-D₃, Frank D. Blum, Wuu-Yung Lin Jan 1998

Deuterium Nmr Of Adsorbed Poly(Methyl Acrylate)-D₃, Frank D. Blum, Wuu-Yung Lin

Chemistry Faculty Research & Creative Works

The dynamics of polymers at interfaces are important in a variety of applications, especially where those applications depend on the mechanical or surface properties. Unfortunately, the surface properties of interfacial species like polymers used in composites are not easily measured macroscopically. Microscopic techniques, especially spectroscopic ones, have been successful. In our laboratory we have been successful in applying NMPR to determine the behavior of absorbed polymers. NMR has several advantages for this kind of study, the principal ones being that it can be used on opaque materials, different nuclei can be used as probes, and interfacial material can sometimes be …


Structural And Magnetic Properties Of Rsr₂Fe₃O₉ (R=La, Y, Pr, And Gd), I. Felner, I. Nowik, A. Mehta, Rajvir Singh, William B. Yelon, V. P. S. Awana, S. X. Dou, Satish K. Malik, A. V. Narlikar Jan 1998

Structural And Magnetic Properties Of Rsr₂Fe₃O₉ (R=La, Y, Pr, And Gd), I. Felner, I. Nowik, A. Mehta, Rajvir Singh, William B. Yelon, V. P. S. Awana, S. X. Dou, Satish K. Malik, A. V. Narlikar

Chemistry Faculty Research & Creative Works

No abstract provided.


Designing Power Bus Decoupling For Cmos Devices, S. Radu, Richard E. Dubroff, Todd H. Hubing, Thomas Van Doren Jan 1998

Designing Power Bus Decoupling For Cmos Devices, S. Radu, Richard E. Dubroff, Todd H. Hubing, Thomas Van Doren

Electrical and Computer Engineering Faculty Research & Creative Works

The adequacy of the DC power bus decoupling for CMOS devices can be determined if the effective board decoupling capacitance, the CMOS load capacitance, the CMOS power dissipation capacitance, the switching time, and the allowable bus noise voltage are known. A simple method is presented for estimating the effective decoupling capacitance. The load and power dissipation capacitance values are shown analytically and experimentally to be closely related to the transient current. The transient current and switching time are used to estimate the transient noise voltage on the power bus


Biological Fixed-Film Systems, Mark W. Fitch, Natalie Pearson, Gene Richards, Joel Gerard Burken Jan 1998

Biological Fixed-Film Systems, Mark W. Fitch, Natalie Pearson, Gene Richards, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.