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Missouri University of Science and Technology

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2001

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Smooth Static And Dynamic Indentation Of A Cantilever Beam, Minggang Zhou, William P. Schonberg Dec 2001

Smooth Static And Dynamic Indentation Of A Cantilever Beam, Minggang Zhou, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The static and dynamic indentation of structural elements such as beams and plates continue to be intriguing problems, especially for scenarios where large area contacts are expected to occur. Standard methods of indentation analyses use a beam theory solution to obtain an overall load-displacement relationship and then a Hertzian contact solution to calculate local stresses under the indenter. However, these techniques are only applicable in a fairly limited class of problems: the stress distribution in the contact region will differ significantly from a Hertzian one when the contact length exceeds the thickness of the beam. The indentation models developed herein …

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Two-Dimensional Fast Evanescent Wave Algorithm, W. C. Chew, L. (Lijun) J. Jiang, S. Velamparambil Dec 2001

Two-Dimensional Fast Evanescent Wave Algorithm, W. C. Chew, L. (Lijun) J. Jiang, S. Velamparambil

Electrical and Computer Engineering Faculty Research & Creative Works

A new fast evanescent wave algorithm (FEWA) is introduced in the two-dimensional (2-D) case. It expands the Green's function into propagating waves and directional evanescent waves. Applying the evanescent wave correction technique, a procedure similar to the traditional MLFMA can be expedited. No buffer region is necessary anymore, and fewer translators are needed. Numerical examples are given to show the features of this method.

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Aisi Standard For Cold-Formed Steel Framing -- Header Design, American Iron And Steel Institute Dec 2001

Aisi Standard For Cold-Formed Steel Framing -- Header Design, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Header Standard document. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. …

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Aisi Standard For Cold-Formed Steel Framing -- Truss Design, American Iron And Steel Institute Dec 2001

Aisi Standard For Cold-Formed Steel Framing -- Truss Design, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Truss Standard document. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. …

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Multimedia Web-Based Resources For Engineering Education: The Media Design And Assessment Laboratory At Umr, Vicki M. Eller, Steve Eugene Watkins, Richard H. Hall, Joel Balestra, Asha S. Rao Dec 2001

Multimedia Web-Based Resources For Engineering Education: The Media Design And Assessment Laboratory At Umr, Vicki M. Eller, Steve Eugene Watkins, Richard H. Hall, Joel Balestra, Asha S. Rao

Business and Information Technology Faculty Research & Creative Works

The Design, Development, and Assessment of Web-Based Multimedia Learning Resources Are Important Aspects of Engineering Education. the Media Design and Assessment Laboratory at the University of Missouri-Rolla Was Established to Facilitate the Interaction between Web Designers and Content Providers. It Was Created under the Auspices of the Instructional Software Development Center. This Paper Will Discuss Design Philosophy in Terms of the Identification of Fundamental Concepts, Development Steps, and Assessment Implementation within the Context of Ongoing Projects. These Projects Include Modules for an Optics Curriculum, Tutorials for an Interdisciplinary Course, and Interactive Software for a Basic Engineering Course.

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Power System Deregulation, Mariesa Crow Dec 2001

Power System Deregulation, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Given the difficulties encountered by the state of California in deregulating their electric power industry, many people are questioning the wisdom of such a move. To better understand the motivation behind deregulation, the author looks at the cost of energy nationwide in the United States. For example, she considers some of the regional energy costs from August 2001.

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Energy Storage Systems For Advanced Power Applications, Aysen Arsoy, Yilu Liu, Paul F. Ribeiro, Brian K. Johnson, Mariesa Crow Dec 2001

Energy Storage Systems For Advanced Power Applications, Aysen Arsoy, Yilu Liu, Paul F. Ribeiro, Brian K. Johnson, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

While energy storage technologies do not represent energy sources, they provide valuable added benefits to improve stability power quality, and reliability of supply. Battery technologies have improved significantly in order to meet the challenges of practical electric vehicles and utility applications. Flywheel technologies are now used in advanced nonpolluting uninterruptible power supplies. Advanced capacitors are being considered as energy storage for power quality applications. Superconducting energy storage systems are still in their prototype stages but receiving attention for utility applications. The latest technology developments, some performance analysis, and cost considerations are addressed. This paper concentrates on the performance benefits of …

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Effect Of Rare Locally Ordered Regions On A Disordered Itinerant Quantum Antiferromagnet With Cubic Anisotropy, Rajesh S. Narayanan, Thomas Vojta Dec 2001

Effect Of Rare Locally Ordered Regions On A Disordered Itinerant Quantum Antiferromagnet With Cubic Anisotropy, Rajesh S. Narayanan, Thomas Vojta

Physics Faculty Research & Creative Works

We study the quantum phase transition of an itinerant antiferromagnet with cubic anisotropy in the presence of quenched disorder, paying particular attention to the locally ordered spatial regions that form in the Griffiths region. We derive an effective action where these rare regions are described in terms of static annealed disorder. A one-loop renormalization-group analysis of the effective action shows that for order-parameter dimensions p<4, the rare regions destroy the conventional critical behavior, and the renormalized disorder flows to infinity. For order-parameter dimensions p>4, the critical behavior is not influenced by the rare regions; it is described by the conventional dirty cubic fixed point. We also discuss the influence of the rare regions on the fluctuation-driven first-order transition …

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World Wide Web Resources For Materials Science, Serge Abrate Dec 2001

World Wide Web Resources For Materials Science, Serge Abrate

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The internet makes technical information readily available in ways that were unthinkable a few years ago. This article shows how the World Wide Web (the web) can be used in a Materials Science class to enrich the educational process. Strategies for finding and evaluating information and are discussed. © 2002 Wiley Periodicals, Inc.

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Inferring Liquid Chaotic Dynamics In Bubble Columns, M. Cassanello, F. Larachi, A. Kemoun, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic Nov 2001

Inferring Liquid Chaotic Dynamics In Bubble Columns, M. Cassanello, F. Larachi, A. Kemoun, M. (Muthanna) H. Al-Dahhan, M. P. Dudukovic

Chemical and Biochemical Engineering Faculty Research & Creative Works

Experiments Carried Out to Study the Liquid Displacements in Bubble Columns Via the Computer Automated Radioactive Particle Tracking Technique Are Analyzed by Means of Lagrangian and Qualitative Dynamics Tools. the Lagrangian Approach Yields the Detailed Motion Sequences of the Tracer as Entrained by the Fast Ascending Bubbles or by the Liquid Flow Alongside the Column Walls. the Qualitative Dynamics Tools, on the Other Hand, Provide Prima Facie Corroboration of Chaos in Liquid Motion based on an Analysis of the Volume-Averaged Kolmogorov Entropy and the Mutual Information Function. Other Features of the Chaotic Motion, the Reconstructed Attractors and the Radial and …

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Emi Mitigation With Multilayer Power-Bus Stacks And Via Stitching Of Reference Planes, Xiaoning Ye, David M. Hockanson, Min Li, Yong Ren, Wei Cui, James L. Drewniak, Richard E. Dubroff Nov 2001

Emi Mitigation With Multilayer Power-Bus Stacks And Via Stitching Of Reference Planes, Xiaoning Ye, David M. Hockanson, Min Li, Yong Ren, Wei Cui, James L. Drewniak, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

General methods for reducing printed circuit board (PCB) emissions over a broad band of high frequencies are necessary to meet EMI requirements, as processors become faster and more powerful. One mechanism by which EMI can be coupled off a PCB or multichip module (MCM) structure is from high-frequency fringing electric fields on the dc power and reference planes at the substrate periphery An approach for EMI mitigation by stitching multiple ground planes together along the periphery of multilayer PCB power-bus stacks with closely spaced vias is reported and quantified in this paper. Power-bus noise induced EMI and coupling from the …

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Earthquake Hazard Assessment Along Designated Emergency Vehicle Priority Access Routes, Neil Lennart Anderson, Hal Baker, Genda Chen, Tom Hertell, David J. Hoffman, Ronaldo Luna, Yulman Munaf, Shamsher Prakash, Paul Michael Santi, Richard Wesley Stephenson Nov 2001

Earthquake Hazard Assessment Along Designated Emergency Vehicle Priority Access Routes, Neil Lennart Anderson, Hal Baker, Genda Chen, Tom Hertell, David J. Hoffman, Ronaldo Luna, Yulman Munaf, Shamsher Prakash, Paul Michael Santi, Richard Wesley Stephenson

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Because of the compelling need to reopen vehicular access routes to Sikeston, Cape Girardeau and St. Louis following a devastating earthquake, Missouri Department of Transportation initiated a study of those portions of US 60 and MO 100 that have been officially designated as emergency vehicle priority access routes. The primary objectives of this study were twofold. Objective 1 was to establish a current subsurface and earthquake design geographic information systems (GIS) database for areas in proximity to designated portions of US 60 and MO 100 (includes counties of Butler, Stoddard, New Madrid, Franklin and St. Louis). Objective 2 was to …

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A Comparison Of Facts Integrated With Battery Energy Storage Systems, Lin Zhang, Shen Chen, Stan Atcitty, Mariesa Crow Nov 2001

A Comparison Of Facts Integrated With Battery Energy Storage Systems, Lin Zhang, Shen Chen, Stan Atcitty, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The integration of energy storage into FACTS devices lead to increased controller flexibility by providing decentralized active power capabilities. Combined FACTS/ESS can improve power flow control, oscillation damping and voltage control. This paper presents a comparison between the dynamic performance of a StatCom, a StatCom/BESS, an SSSC, an SSSC/BESS and a UPFC. Experimental verification is also presented.

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Monte Carlo Simulations Of Peptide Adsorption On Solid Surfaces (Monte Carlo Simulations Of Peptide Adsorption), D. Song, Daniel Forciniti Nov 2001

Monte Carlo Simulations Of Peptide Adsorption On Solid Surfaces (Monte Carlo Simulations Of Peptide Adsorption), D. Song, Daniel Forciniti

Chemical and Biochemical Engineering Faculty Research & Creative Works

Monte Carlo (MC) simulations of a short peptide in bulk water and at charged and neutral surfaces were performed. To pursue the objective of finding whether or not the water structure around the peptide changes upon adsorption and how these changes affect the orientation of the peptide at the surface, the water structure around the peptide in the bulk and at charged and neutral surfaces were compared by analyzing the pair correlation functions (PCFs) between selected groups in the peptide and the surrounding water. In general, evidence was obtained that water is not homogeneously distributed over the peptide surface.

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Quantifying Smt Decoupling Capacitor Placement In Dc Power-Bus Design For Multilayer Pcbs, Jun Fan, James L. Drewniak, James L. Knighten, Norman W. Smith, Antonio Orlandi, Thomas Van Doren, Todd H. Hubing, Richard E. Dubroff Nov 2001

Quantifying Smt Decoupling Capacitor Placement In Dc Power-Bus Design For Multilayer Pcbs, Jun Fan, James L. Drewniak, James L. Knighten, Norman W. Smith, Antonio Orlandi, Thomas Van Doren, Todd H. Hubing, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

Noise on a dc power-bus that results from device switching, as well as other potential mechanisms, is a primary source of many signal integrity (SI) and electromagnetic interference (EMI) problems. Surface mount technology (SMT) decoupling capacitors are commonly used to mitigate this power-bus noise. A critical design issue associated with this common practice in high-speed digital designs is placement of the capacitors with respect to the integrated circuits (ICs). Local decoupling, namely, placing SMT capacitors in proximity to ICs, is investigated in this study. Multilayer PCB designs that employ entire layers or area fills for power and ground in a …

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Closure To Discussion Of "Voltage Stability Analysis: V-Q Power Flow Simulation Versus Dynamic Simulation", Badrul H. Chowdhury, C. W. Taylor Nov 2001

Closure To Discussion Of "Voltage Stability Analysis: V-Q Power Flow Simulation Versus Dynamic Simulation", Badrul H. Chowdhury, C. W. Taylor

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Size-Induced Lattice Relaxation In Ceo₂ Nanoparticles, X.-D. Zhou, Wayne Huebner Nov 2001

Size-Induced Lattice Relaxation In Ceo₂ Nanoparticles, X.-D. Zhou, Wayne Huebner

Materials Science and Engineering Faculty Research & Creative Works

Size-induced lattice relaxation was observed for nanoscale CeO2 single crystals with an average size from 4 to 60 nm. Results showed the finest crystallites exhibited no strain-induced line broadening, while high temperature annealing resulted in larger grain sizes and significant strains. The observed shift in the x-ray diffraction lattice parameters was assumed to be due to the formation of defects on the lattice, specifically oxygen vacancies. Modeling revealed that the oxygen vacancy concentration ([V••O]) was found to be ≈4 x 1020/cm3 for the 4 nm crystallites, and decreased two orders of magnitude for …

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Dc Power-Bus Modeling And Design With A Mixed-Potential Integral-Equation Formulation And Circuit Extraction, Jun Fan, James L. Drewniak, Hao Shi, James L. Knighten Nov 2001

Dc Power-Bus Modeling And Design With A Mixed-Potential Integral-Equation Formulation And Circuit Extraction, Jun Fan, James L. Drewniak, Hao Shi, James L. Knighten

Electrical and Computer Engineering Faculty Research & Creative Works

Application of a circuit extraction approach based on a mixed-potential integral equation formulation (CEMPIE) for dc power-bus modeling in high-speed digital designs is detailed herein. Agreement with measurements demonstrates the effectiveness of the approach. Dielectric losses are included into the calculation of Green's functions, and thus, incorporated into the rigorous first principles formulation. A SPICE model is then extracted from the discretized integral equation. A quasistatic approximation is used for Green's functions to keep the extracted circuit elements frequency independent. Previous work has established a necessary meshing criterion in order to ensure accuracy for a given substrate thickness and dielectric …

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Dc Power-Bus Design Using Fdtd Modeling With Dispersive Media And Surface Mount Technology Components, Xiaoning Ye, Marina Koledintseva, Min Li, James L. Drewniak Nov 2001

Dc Power-Bus Design Using Fdtd Modeling With Dispersive Media And Surface Mount Technology Components, Xiaoning Ye, Marina Koledintseva, Min Li, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

DC power-bus modeling in high-speed digital design using the finite-difference time-domain (FDTD) method is demonstrated herein. The dispersive character of the dielectric layers used in printed circuit board substrates is taken into account in this study. In particular, FR-4 is considered. The complex permittivity of the dielectric is approximated by a Debye model. A wide-band frequency response (100 MHz-5 GHz) is obtained through a single FDTD simulation. Good agreement is achieved between the modeled and measured results for a typical dc power-bus structure with multiple surface mount technology (SMT) decoupling capacitors placed on the printed circuit board (PCB). The FDTD …

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Three-Body Coulomb Problem Probed By Mapping The Bethe Surface In Ionizing Ion-Atom Collisions, Robert Moshammer, Appathurai N. Perumal, Michael Schulz, V. D. Rodriguez, Holger Kollmus, Rido Mann, Siegbert Hagmann, Joachim Hermann Ullrich Nov 2001

Three-Body Coulomb Problem Probed By Mapping The Bethe Surface In Ionizing Ion-Atom Collisions, Robert Moshammer, Appathurai N. Perumal, Michael Schulz, V. D. Rodriguez, Holger Kollmus, Rido Mann, Siegbert Hagmann, Joachim Hermann Ullrich

Physics Faculty Research & Creative Works

The three-body Coulomb problem has been explored in kinematically complete experiments on single ionization of helium by 100 MeV / u C 6 + and 3.6 MeV / u u 5 3 + impact. Low-energy electron emission (E e < 150 eV ) as a function of the projectile deflection ϑ p (momentum transfer), i.e., the Bethe surface [[15]], has been mapped with Δ ϑ p ± 25 nanoradian resolution at extremely large perturbations (3.6 MeV / uAu53+ ) where single ionization occurs at impact parameters of typically 10 times the He K -shell radius. The experimental data are not in agreement with state-of-the-art continuum distorted wave-eikonal initial state theory.

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Electron-Impact Excitation To The 4p⁵5s And 4p⁵5p Levels Of Kr | Using Different Distorted-Wave And Close-Coupling Methods, Arati K. Dasgupta, Klaus Bartschat, D. Vaid, Alexei N. Grum-Grzhimailo, Don H. Madison, Milan Blaha, John L. Giuliani Nov 2001

Electron-Impact Excitation To The 4p⁵5s And 4p⁵5p Levels Of Kr | Using Different Distorted-Wave And Close-Coupling Methods, Arati K. Dasgupta, Klaus Bartschat, D. Vaid, Alexei N. Grum-Grzhimailo, Don H. Madison, Milan Blaha, John L. Giuliani

Physics Faculty Research & Creative Works

Electron-impact excitation of the 4p55s and 4p55p levels of Kr I has been investigated in detail by calculating cross sections using distorted-wave and close-coupling approaches. The results are presented from the excitation thresholds up to 50 eV incident energy. They are contrasted among the different calculations and compared with other theoretical predictions and experimental data. Significant disagreement is found with many of the recent experimental data of Chilton et al. [Phys. Rev. A 62, 032714 (2000)].

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Practical Issues For The Application Of High-Performance Concrete To Highway Structures, John J. Myers, Yumin Yang Nov 2001

Practical Issues For The Application Of High-Performance Concrete To Highway Structures, John J. Myers, Yumin Yang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In recent years, the advantages of high-performance concrete (HPC) have been well documented. Among others, these advantages include enhanced design flexibility and improved durability performance that results in reduced maintenance costs and an increased service life. Despite these obvious benefits, the implementation of HPC has been very slow. This can be attributed to several factors including the uncertainty related to current design codes and a lack of familiarity of designers and contractors with practices and requirements for proper design and construction of high-performance concrete structures. This paper introduces and discusses several fundamental issues that affect the implementation of HPC and …

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A New Crystalline Phase (Na2o · 8teo2) In The Na2o-Teo2 System, Dongmei Zhu, Wancheng Zhou, C. S. Ray Nov 2001

A New Crystalline Phase (Na2o · 8teo2) In The Na2o-Teo2 System, Dongmei Zhu, Wancheng Zhou, C. S. Ray

Materials Science and Engineering Faculty Research & Creative Works

The formation and decomposition of NT8 crystal phase was investigated using differential scanning calorimetry (DSC) and x-ray diffraction analysis (XRD). DSC measurements indicated that all the glasses used in the investigation crystallized at about 330±5 °C. Results suggested that the NT8 phase, which was very stable at 330 °C was not stable at or above 340 °C and readily decomposed to NT4 and TeO2.

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Ultrasonic Characterization Of Poling In Lead Zirconate Titanate Ceramics, James R. Friend, Eric Jamieson, Marvin Pennell, Wayne Huebner Oct 2001

Ultrasonic Characterization Of Poling In Lead Zirconate Titanate Ceramics, James R. Friend, Eric Jamieson, Marvin Pennell, Wayne Huebner

Materials Science and Engineering Faculty Research & Creative Works

A method for measuring the spatial variation of the macroscopic poling state of a piezoelectric material using an ultrasonic transducer is described. The relatively simple method clearly indicates the distribution of poling within the material, demonstrated by the testing of a collection of partially poled lead zirconate titanate samples.

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Highly Plasma Etch-Resistant Photoresist Composition Containing A Photosensitive Polymeric Titania Precursor, Tony D. Flaim, Douglas J. Guerrero, Michelle R. Fowler, William Joseph James, Vladimir Petrovsky, Harlan U. Anderson Oct 2001

Highly Plasma Etch-Resistant Photoresist Composition Containing A Photosensitive Polymeric Titania Precursor, Tony D. Flaim, Douglas J. Guerrero, Michelle R. Fowler, William Joseph James, Vladimir Petrovsky, Harlan U. Anderson

Chemistry Faculty Research & Creative Works

A composition is derived from an addition polymerizable organotitanium polymer which upon exposure to an oxygen plasma or baking in air, is converted to titanium dioxide (titania) or is converted to a mixed, titanium-containing metal oxide. The metal oxide formed in situ imparts etch- resistant action to a patterned photoresist layer. The composition may also be directly deposited and patterned into permanent metal oxide device features by a photolithographic process.

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Mapping Of The Bethe Surface In Single-Ionization Ion-Atom Collisions, Ronald E. Olson, J. Fiol Oct 2001

Mapping Of The Bethe Surface In Single-Ionization Ion-Atom Collisions, Ronald E. Olson, J. Fiol

Physics Faculty Research & Creative Works

The three-body Coulomb problem is explored using classical-trajectory Monte Carlo and continuum distorted-wave methods that include all interactions, including the nuclear-nuclear term. Calculations for low-energy electron emission as a function of projectile deflection, the Bethe surface, are compared with experiment for single ionization of He by 100 MeVu-1 C6+ and 3.6 MeV u-1 Au53+. Good agreement is realized for the C6+ system. For Au53+ poor agreement with experiment is obtained, indicating that the proposed lack of the nuclear-nuclear interaction is not the source of the discrepancy. The calculations further show that significant cross sections …

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The Effects Of Via Transitions On Differential Signals, Chen Wang, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, James L. Drewniak Oct 2001

The Effects Of Via Transitions On Differential Signals, Chen Wang, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Vias in differential transmission lines have been modeled using the finite-difference time-domain (FDTD) method. The velocity that the differential signal propagated through the vias was estimated. Differential S-parameters were calculated up to 50 GHz. Below 10 GHz, the differential signal can propagate through vias without much reflection and distortion. However, as frequency increases, the reflection from the vias and the loss of differential power become significant.

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Metrics-Guided Quality Management For Component-Based Software Systems, Sahra Sedigh, Arif Ghafoor, Raymond A. Paul Oct 2001

Metrics-Guided Quality Management For Component-Based Software Systems, Sahra Sedigh, Arif Ghafoor, Raymond A. Paul

Electrical and Computer Engineering Faculty Research & Creative Works

The growing reliance on commercial-off-the-shelf (COTS) components for developing large-scale projects introduces a new paradigm in software Engineering; which requires the design of new software development and business processes. Large scale component reuse leads to savings in development resources, enabling these resources to be applied to areas such as quality improvement. These savings come at the price of integration difficulties, performance constraints, and incompatibility of components from multiple vendors. Relying on COTS components also increases the system''s vulnerability to risks arising from third-party development, which can negatively affect the quality of the system, as well as causing expenses not incurred …

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A Simple, Robust, And On-Site Microwave Technique For Determining Water-To-Cement Ratio (W/C) Of Fresh Portland Cement-Based Materials, K. Mubarak, Karl Joseph Bois, R. Zoughi Oct 2001

A Simple, Robust, And On-Site Microwave Technique For Determining Water-To-Cement Ratio (W/C) Of Fresh Portland Cement-Based Materials, K. Mubarak, Karl Joseph Bois, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Inspection and evaluation of cement-based materials such as concrete is of great interest to the construction industry. In particular, real-time and on-site evaluation of water-to-cement ratio (w/c) is an important practical issue, since the compressive strength of a concrete structure is significantly influenced by its w/c. Currently, there is no single real-time, on-site, relatively in-expensive, easy-to-implement, and operator friendly technique for evaluating this parameter. Microwave nondestructive testing and evaluation techniques have shown great promise when used for inspection and evaluation of the properties of cement-based materials. In this paper, the optimal design of a monopole antenna probe used to evaluate …

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Pilot Study: Lateral Braced C-Sections Under Bending, B. Beshara, Roger A. Laboube Oct 2001

Pilot Study: Lateral Braced C-Sections Under Bending, B. Beshara, Roger A. Laboube

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The overall behavior under uniform load of cold-formed steel C-sections assemblies was investigated. Each test assembly consisted of C-sections acting as beams having a track section to restrain its ends. A lateral brace to restrain the C-sections from rotation was provided at mid-span. To better understand the influence of the brace on the flexural behavior, an experimental investigation was carried out with particular emphasis placed on the study of the effect of the mid-span brace connection when wallboard was attached to the tension flange. The tested moment capacities are compared to predictions based on the 1996 edition American Iron and …

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