Physical Sciences and Mathematics Commons^™

Computer Simulations Of Electromigration Based On A Molecular Dynamics Approach, John Stephen Peake

Electrical & Computer Engineering Theses & Dissertations

Most research on electromigration has centered around macroscopic simulations of electromigration where a value for the diffusion coefficient was assumed to be spatially uniform throughout the material. The research in this thesis goes a step further and, through microscopic molecular dynamics computer simulations, calculates and updates the atomic drift velocity and atomic position as a function of time to analyze how various defects within the conductor affect these quantities. The simulations are carried out with defects in the form of dislocation half-planes placed in different locations within the simulation space. The atomic drift velocity and position changes derived from these …

Chemical Modification Of Cvd Diamond Electrodes, Robert Matthew Johnson

Chemistry & Biochemistry Theses & Dissertations

The micro-array behavior of boron doped CVD diamond thin film electrodes has been studied in acetonitrile containing two redox couples. The analytical technique employed in these studies was cyclic voltammetry. One system is 0.4 mM ferrocene containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAH). This reversible redox system is not only well-known, but also involves only one electron transfer with no breakage/formation of chemical bonds, thus making it a simple system for analysis. The second test is 0.8 mM cobaltocenium hexafluorophosphate, with 0.4 mM ferrocene as an internal standard. Unlike ferrocene, which is neutral initially, cobaltocenium is positively charged, and is reduced …

สรุปข่าวสิ่งแวดล้อม : กรกฎาคม-กันยายน 2541

Thai Environment

No abstract provided.

ปรอทในก๊าซธรรมชาติ, มารยาท วีรกรม

Thai Environment

No abstract provided.

ความสำคัญของคุณภาพน้ำต่อทรัพยากรสัตว์น้ำจืด ในอ่างเก็บน้ำลำตะคอง จังหวัดนครราชสีมา, เดชาพล รุกขมธุร์

Thai Environment

No abstract provided.

Validation Of Waimss Incident Duration Estimation Model, Wei Wu, Pushkin Kachroo, Kaan Ozbay

Electrical & Computer Engineering Faculty Research

This paper presents an effort to validate the traffic incident duration estimation model of WAIMSS (wide area incident management support system). Duration estimation model of WAIMSS predicts the incident duration based on an estimation tree which was calibrated using incident data collected in Northern Virginia. Due to the limited sample size, a full scale test of the distribution, mean and variance of incident duration was performed only for the root node of the estimation tree, white only mean tests were executed at all other nodes whenever a data subset was available. Further studies were also conducted on the model error …

Wide-Area Incident Management System On The Internet, Kaan Ozbay, Pushkin Kachroo

Electrical & Computer Engineering Faculty Research

The incident management process consists of four sequential steps-incident detection, response, clearance and recovery. Each of these components comprises of a number of operations and coordinated decision-making between the agencies involved. The provision of computer based support tools for the personnel involved will help develop appropriate strategies and increase efficiency and expediency. Existing systems are developed on various traditional computing platforms. However, with the advent of World Wide Web and Internet based programming tools such as Java, it is now possible to develop platform independent decision support tools for the incident management agencies. Any agency will be able to use …

The Development And Characterisation Of A Red-Sensitised Photopolymer Holographic Recording Material, Clodagh Feely

Doctoral

The development and characterisation of a photopolymerisable photopolymer holographic recording material, for red sensitisation is described. The material comprises dye (methylene blue), an electron donor (triethanolamine) and monomer (acrylamide and methylene-bis-acrylamide). A binder is also included (poly(vinylalcohol) to allow recording in dry layer format. One of the main advantages of the material is its ability to self-develop, which makes it highly suitable for a range of applications which includes the fabrication of Holographic Optical Elements (HOEs). The optimisation of the material formula for red-sensitisation using holographic techniques is described. Diffraction efficiencies of over 70% were obtained in 25 seconds with …

Wiyn Open Cluster Study. I. Deep Photometry Of Ngc188, Ted Von Hippel, Ata Sarajedini

Publications

We have employed precise and carefully calibrated V - and I - band photometry of NGC 188 at WIYN Observatory to explore the cluster luminosity function (LF) and study the cluster white dwarfs. Our photometry is offset by V = 0.052 (fainter) from that of Sandage and Eggen & Sandage. All published photometry for the past three decades has been based on these two calibrations, which are in error by 0.05 ± 0.01. We employ the Pinsonneault et al. fiducial open cluster main sequence to derive a distance modulus of 11.43 ± 0.08 and E(B - V )=0.09, with …

Circulation, Vol. 6, No. 1, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Fall 1998 issue of CCPO Circulation featuring article "Renewed Effort by Mexican Oceanographers to Understand the Dynamics of Coastal Lagoons"

Reactions Of Chlorine Atoms With Aromatic Compounds, Barbara O'Leary

Masters

This thesis presents the results of kinetic studies on the reactions of chlorine atoms with a series of aromatic compounds. (please see full text for complete abstract)

Variability Analysis Of Discrete Cosine Transform Coefficient (Dctc) Features For Speech Processing, Bingjun Dai

Electrical & Computer Engineering Theses & Dissertations

In this research, the variability of Discrete Cosine Transform Coefficient (DCTC) features was investigated. Additionally, a new pitch-synchronous processing method was explored to increase the stability of features and to reduce window effects when compared to the regular method. The noise sources that lead to feature variability were analyzed, and different smoothing methods were tested. It was found that longer frames, frequency warping, time smoothing of the log spectrum, and DCS level time smoothing, all help reduce DCTC variability and increase classification performance. The pitch­ synchronous method was implemented with Matlab. Important processing methods, including pitch period estimation, time­ domain …

Earth News, Fall 1998, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- Faculty Achievements and Activities
--- 1998 Earth Science Graduates
--- Student Research Presentations
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Earth Science Majors
--- Observatory: Room with a Stellar View
--- Gifts to the Department of Earth Science
--- 1998 Scholarship and Award Recipients
--- Earth Science Seminar Series
--- UNI Students Get Up Close and Personal with Nature
--- Earth Science Alumni Notes

Mountain Evolution And Environmental Changes Of Huangshan, China, P.-H. Huang, Robert F. Diffendal Jr., M. Yang, Patricia E. Helland

Department of Earth and Atmospheric Sciences: Faculty Publications

Huangshan (Yellow Mountain) is located in southern part of the lower reaches of the Yangtze River. The highest Lotus Flower peak is 1,864 m above sea level. Formative ages of the Huangshan and its granite, process of mountain geomorphic evolution from the Eocene to Quaternary, environmental changes of Quaternary, formative origin of beautiful peaks and fascinating rocks were studied and questionable "Pleistocene glaciation" was also discussed in this paper.

Automated Highway Systems, Bruce M. Mcmillin, Kristen L. Sanford

Computer Science Faculty Research & Creative Works

Intelligent transportation systems (ATS) have received much attention in the transportation community and by the government in the past decade. The technology is an extension of intelligent vehicle highway systems to include transportation modes beyond highways. Major elements of ITS include: advanced traffic management systems; advanced traveller information systems; automated highway systems; the Intelligent Vehicle Initiative; and advanced commercial vehicle systems. ITS initiatives are proposed for both urban and rural areas to increase transportation system capacity by more fully utilizing the existing transportation system and improve transportation system safety. The feasibility of realizing a fully automated highway system is discussed.

Design And Implementation Of A Maritime Conflict Prediction System, Wee-Keong Ng, Ee Peng Lim, Wen Jing Hsu, Yy Cao

Research Collection School Of Computing and Information Systems

Maritime conflicts have serious impacts on Singapore and the surrounding region both economically and environmentally. This is particularly severe for conflicts such as collisions between large vessels or tankers carrying oil and chemicals. Thus, it is in the interests of the Maritime and Port Authority of Singapore (MPA) to avoid collisions or near-collisions among such vessels navigating through Singapore waters. Existing systems used by MPA predict potential maritime conflicts arising within a short and fixed time horizon. The system produces inconsequential warnings that are often ignored. In this paper, we describe an advanced computerbased system designed to assist in the …

Analysis Of The Interpolation Error Between Multiresolution Images, Bryan S. Morse

Faculty Publications

Many rendering or image-analysis systems require calculation of versions of an image at lesser resolutions than the original. Because the filtering required to perform such calculations accurately cannot typically be done in real time, many systems use interpolation between images at precalculated resolutions. This discrete sampling of the scale component of multiresolution image spaces is analogous to spatial sampling in discrete images. This paper quantifies and bounds the error that can be introduced during such interpolation as a function of the scale-space sampling rate used. A method is presented that uses the diffusion equation to relate spatial derivatives to scale …

Isophote-Based Interpolation, Bryan S. Morse, Duane Schwartzwald

Faculty Publications

Standard methods for image interpolation are based on smoothly fitting the image intensity surface. Recent edge-directed interpolation methods add limited geometric information (edge maps) to build more accurate and visually appealing interpolations at key contours in the image. This paper presents a method for geometry-based interpolation that smoothly fits the isophote (intensity level curve) contours at all points in the image rather than just at selected contours. By using level set methods for curve evolution, no explicit extraction or representation of these contours is required (unlike earlier edge-directed methods). The method uses existing interpolation techniques as an initial approximation and …

A Messy, But Instructive, Case Study In Design Of Experiments, Leroy A. Franklin, Belva J. Cooley, Gary Elrod

Mathematical Sciences Technical Reports (MSTR)

A company manufacturing fans wished to conduct an experimental design to determine the best combination of three factors affecting the breaking torque of the fans. Analysis of the data ceased to be straightforward when the authors found that the data failed the test for homogeneity of variances. After unsuccessfully attempting to transform the data and thereby meet the assumptions necessary to carry on the analysis, the authors relied upon a graphical analysis and a careful study of the means for each design point. This paper describes a statistically sound but novel strategy used to complete the analysis.

A Zero Point And Accidental Errors For Published Values Of [Fe/H] For Cool Giants, B. J. Taylor

Faculty Publications

This paper is one of a series based on published values of [Fe/H] for late-type evolved stars. Only values of [Fe/H] from high-dispersion spectroscopy or related techniques are used. The narrative in this paper begins at a point where mean values of [Fe/H] have been derived for xiVir, alphaBoo, betaGem, and the Hyades giants. By using these stars as standard stars when necessary, a zero-point data base is assembled. This data base is then expanded into its final version by correcting and adding additional data in a step-by-step process. As that process proceeds, data comparisons are used to establish rms …

Construction Of Some Combinatorial Designs Arising Out Of Statistical Experiments., Tridib Kumar Dutta Dr.

Doctoral Theses

Chis dissertation considers construction of two kinds of combi natorial sesigns as used by statisticians: repeated measurements designs (RMDS) and symmetric balanced squares (SBSS). 1.1. REPEATED MEASUREMENTS DESIGNS The researchers need to perform experiments where each experimental unit receives some or all of the treatments in an appropriate sequence over a number of successive periods. These designs are known by several names in the statistical 1iterature: repeated measurements designs, crossover or changeover designs, (multiple) time series designs, and before-after designs. If there are n experimental units 1,2, ... n, t treatments and p periods 0,1, .. .p-1, applied, then an …

Certalert: Grasses Attractive To Hazardous Wildlife

Other Bird Strike and Aviation Materials

Recently, several reports have been received of airport owners or airport contractors planting disturbed areas (construction sites, re-grading projects, etc) with seed mixtures containing brown-top millet. All millets are a major attractant to doves and other seed eating birds.

An Analysis Of Temperature Dependent Photoluminescence Line Shapes In Ingan, John S. Colton, K. L. Teo, P. Y. Yu, E. R. Weber, M. F. Li, W. Lui, K. Uchida, H. Tokunaga, N. Akutsu, K. Matsumoto

Faculty Publications

Photoluminescence (PL) line shapes in InGaN multiple quantum well structures have been studied experimentally and theoretically between 10 and 300 K. The higher temperature PL spectra can be fitted qualitatively with a thermalized carrier distribution and a broadened joint-density-of-states. The low temperature PL line shapes suggest that carriers are not thermalized, as a result of localization by band-gap fluctuations. We deduce a localization energy of ~7 meV as compared with an activation energy of ~63 meV from thermal quenching of the PL intensity. We thus conclude that this activation energy and the band-gap fluctuation most likely have different origins.

Near-Infrared Galaxy Counts To J And K ∼ 24 As A Function Of Image Size, Matthew A. Bershady, James D. Lowenthal, David C. Koo

Astronomy: Faculty Publications

We have used the Keck 10 m telescope to count objects as a function of image size in two high Galactic latitude Ðelds covering 1.5 arcmin2 and reaching 50% completeness depths of K \ 24 and J \ 24.5 for stellar sources. Our counts extend D1 mag deeper in K than those of surveys with other telescopes; complement other Keck surveys in the K-band that provide counts at comparable or shallower depths but that have not utilized image structure; and extend by several magnitudes the J-band counts from brighter surveys using smaller telescopes that cover larger areas. We Ðnd the …

Comparison Between Dc-8 And Er-2 Species Measurements In The Tropical Middle Troposphere: No, NoY, O3, Co2, Ch4, And N2O, A. J. Weinheimer, D. D. Montzka, T. L. Campos, J. G. Walega, B. A. Ridley, Stephen G. Donnelly Ph.D., E. R. Keim, L. A. Del Negro, M. H. Proffitt, J. J. Margitan, K. A. Boering, A. E. Andrews, B. C. Daube, S. C. Wofsy, B. E. Anderson, J. E. Collins, G. W. Sachse, S. A. Vay, J. W. Elkins, P. R. Wamsley, E. L. Atlas, F. Flocke, S. Schauffler, C. R. Webster, R. D. May, M. Loewenstein, J. R. Podolske, T. P. Bui, K. R. Chan, S. W. Bowen, M. R. Schoeberl, L. R. Lait

Chemistry Faculty Publications

We compare measurements of six species taken aboard NASA DC-8 and ER-2 aircraft during two flight legs in the tropical middle troposphere near Hawaii. NO, NOy, O3, CH4, and N2O measurements agree to within the limits set by the known systematic errors. For CO2, which can be measured with better relative precision than the other five species, differences in measured values from the two platforms are slightly larger than expected if the air masses sampled by the two aircraft were indeed similar in CO2 composition to better than 0.08%. Copyright 1998 by the American Geophysical Union.

Ua12/2/1 College Heights Herald, Vol. 74, No. 7, Wku Student Affairs

WKU Administration Documents

WKU campus newspaper reporting campus, athletic and Bowling Green, Kentucky news. This issue contains articles:

• Harper, Molly. General Education Requirements May Toughen
• Lanter, Charlie. Staff Left in Dark by Staff Advisory Council Committee
• Goddard, Holly. Reclaiming the Night – Sexual Assault
• Goetz, Kristina. Dropping Masks, Women Reveal Pain, Strength – Sexual Assault
• Karen, Mattias. Intramural Field Opens After 5-Year Delay
• Standing Up Takes Courage – Diddle Arena
• Tabor, Chris. Editorial Cartoon: Big Red Pointing Way to Alumni Seating
• Durbin, Derek. U.S. Policy Invites Terrorism
• Ward, Teresa. Column on Grammar Mistakes Had Some Errors
• Chooljian, Cheryl. Hunting: Alternative to TV?
• Whitt, …

Monte Carlo Renormalization Of 2d Simplicial Quantum Gravity Coupled To Gaussian Matter, Simon Catterall, Eric B. Gregory, G. Thorleifsson

Physics - All Scholarship

We extend a recently proposed real-space renormalization group scheme for dynamical triangulations to situations where the lattice is coupled to continuous scalar fields. Using Monte Carlo simulations in combination with a linear, stochastic blocking scheme for the scalar fields we are able to determine the leading eigenvalues of the stability matrix with good accuracy both for c = 1 and c = 10 theories.

New Analytical Results On Anisotropic Membranes, Mark Bowick, Alex Travesset

Physics - All Scholarship

We report on recent progress in understanding the tubular phase of self-avoiding anisotropic membranes. After an introduction to the problem, we sketch the renormalization group arguments and symmetry considerations that lead us to the most plausible fixed point structure of the model. We then employ an epsilon-expansion about the upper critical dimension to extrapolate to the physical interesting 3-dimensional case. The results are $\nu=0.62$ for the Flory exponent and $\zeta=0.80$ for the roughness exponent. Finally we comment on the importance that numerical tests may have to test these predictions.

Comment On A Critique Of The Instantaneous Normal Mode (Inm) Approach To Diffusion, T. Keyes, Wu Xiong Li, Ulrich Zurcher

Physics Faculty Publications

A critique of the instantaneous normal mode (INM) theory of diffusion by Gezelter, Rabani, and Berne (GRB) [J. Chem. Phys. 107, 4618 (1997)] is analyzed. GRB assert that imaginary-frequency INM are corrupted with modes unrelated to barrier crossing, that proposals for removing such nondiffusive (ND) modes are inadequate, and thus that INM cannot be used to predict the self-diffusion constant, D. In rebuttal it is argued that Lennard-Jones, the system studied by GRB, is anamolously rich in ND modes. INM in molecular liquids are shown to behave as excellent indicators of barrier crossing. Even in LJ ND-INM, while plentiful, do …

Simultaneous Formation Of Functional Leading And Lagging Strand Holoenzyme Complexes On A Small, Defined Dna Substrate, Anthony J. Berdis, Stephen J. Benkovic

Chemistry Faculty Publications

The biochemical characterization of leading and lagging strand DNA synthesis by bacteriophage T4 replication proteins has been addressed utilizing a small, defined primer/template. The ATP hydrolysis activity of 44/62, the clamp loading complex responsible for holoenzyme assembly, was monitored during assembly of both the leading and lagging strand holoenzyme complex. The ATPase activity of 44/62 diminishes once a functional holoenzyme is assembled on both the leading and lagging strand. The assembly of the lagging strand holoenzyme is facilitated by several factors including biotinylated streptavidin blocks at the end of the fork strands, preassembly of the leading strand holoenzyme, and by …