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Selected Works

Selected Works

2004

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Articles 31 - 60 of 147

Full-Text Articles in Physical Sciences and Mathematics

The Hanle Effect As A Diagnostic Of Magnetic Fields In Stellar Envelopes Iv. Application To Polarized P Cygni Wind Lines., R. Ignace, K. H. Nordsieck, J. P. Cassinelli Jul 2004

The Hanle Effect As A Diagnostic Of Magnetic Fields In Stellar Envelopes Iv. Application To Polarized P Cygni Wind Lines., R. Ignace, K. H. Nordsieck, J. P. Cassinelli

Richard Ignace

The Hanle effect has been proposed as a new diagnostic of circumstellar magnetic fields for early-type stars, for which it is sensitive to field strengths in the 1-300 G range. In this paper we compute the polarized P-Cygni line profiles that result from the Hanle effect. For modeling the polarization, we employ a variant of the ``last scattering approximation''. For cases in which the Sobolev optical depths are greater than unity, the emergent line intensity is assumed to be unpolarized; while for smaller optical depths, the Stokes source functions for the Hanle effect with optically thin line scattering are used. …


Ws-Net: A Petri-Net Based Specification Model For Web Services, Jia Zhang, Carl Chang, Jen-Yao Chung, Seong Kim Jun 2004

Ws-Net: A Petri-Net Based Specification Model For Web Services, Jia Zhang, Carl Chang, Jen-Yao Chung, Seong Kim

Jia Zhang

No abstract provided.


Wind Shear, Christopher Roman Jun 2004

Wind Shear, Christopher Roman

Christopher N. Roman

Article that appeared in Sail magazine (ISSN: 0036-2700).


Assisting Seller Pricing Strategy Selection For Electronic Auction, Jia Zhang, Ning Zhang, Jen-Yao Chung Jun 2004

Assisting Seller Pricing Strategy Selection For Electronic Auction, Jia Zhang, Ning Zhang, Jen-Yao Chung

Jia Zhang

No abstract provided.


Ab Initio And 1H Nmr Study Of The Zn(Ii) Complexes Of A Nido- And A Closo-Carboranylporphyrin, Petia Bobadova-Parvanova, Yuko Oku, Anura Wickramasinghe, Randall W. Hall, Graca H. Vicente Jun 2004

Ab Initio And 1H Nmr Study Of The Zn(Ii) Complexes Of A Nido- And A Closo-Carboranylporphyrin, Petia Bobadova-Parvanova, Yuko Oku, Anura Wickramasinghe, Randall W. Hall, Graca H. Vicente

Randall W. Hall

n ab initio study of a promising nido-carboranylporphyrin for the boron neutron capture therapy of tumors, and of its closo precursor is reported. Base-induced deboronation of neutral ZnDCP, believed to exist as a mixture of 3 stereoisomers, produces the tetraanionic ZnDCP4- as a complex mixture of isomers. 1H NMR data and ab initio calculations support these findings. The position of the axial pyridine ligand in ZnDCP4- and the orientation of the endo hydrogen atoms on the open faces of the nido-carborane cages significantly influence the total energy of the ZnDCP4- structures. It is suggested that the "cocktail" of isomers possibly …


Ester Type Banana-Shaped Liquid Crystalline Monomers: Synthesis And Physical Properties, Katalin Fodor-Csorba, Aniko Vajda, Antal Jakli, Christian Slugovc, Gregor Trimmel, Dietrich Demus, Eszter Gacz-Baitz, Sandor Holly, Giancarlo Galli Jun 2004

Ester Type Banana-Shaped Liquid Crystalline Monomers: Synthesis And Physical Properties, Katalin Fodor-Csorba, Aniko Vajda, Antal Jakli, Christian Slugovc, Gregor Trimmel, Dietrich Demus, Eszter Gacz-Baitz, Sandor Holly, Giancarlo Galli

Antal Jakli

New ester-type banana (bent-shaped) monomers, 1,3-phenylene bis[4'-(alken-1-yloxy)-biphenyl-4-carboxylate] s Ia - Vb, with different substituent(s) on the central phenyl ring (H, CH3, Cl or NO2) and alkenyl tails in the side arms ( decenyl or undecenyl) were prepared. The analogues IIIa - IVb with 4-chloro- or 4,6-dichloro-substituents exhibited a nematic phase, while Va, Vb with 2-nitro-substituent showed a B-7 phase at relatively low temperature. All the compounds were stable, no degradation or polymerization was observed under applied electric fields or heat treatments. Electro-hydrodynamic instabilities were observed in the nematic phase of each sample. In the B-7 phase of Vb there was …


Constraining The Exhumation And Burial History Of The Safod Pilot Hole With Apatite Fission Track And (U-Th)/He Thermochronometry, Ann Blythe, M D’Alessio, R Bürgmann Jun 2004

Constraining The Exhumation And Burial History Of The Safod Pilot Hole With Apatite Fission Track And (U-Th)/He Thermochronometry, Ann Blythe, M D’Alessio, R Bürgmann

Ann Blythe

[1] The San Andreas Fault Observatory at Depth (SAFOD) pilot hole traverses the upper 2 km of a site 1.8 km west of the San Andreas fault (SAF) near Parkfield, California. In order to evaluate the burial and exhumation history of the site and its relationship to the kinematics and mechanics of the SAF, we use 15 apatite fission-track (FT) and 5 (U-Th)/He analyses from pilot hole samples to document their thermal history. Sample ages decrease with depth: FT and (U-Th)/He ages range from ∼60 and ∼31 Ma, respectively, in the upper 800 m of the hole to ∼3 and …


Bounding The Firing Synchronization Problem On A Ring, André Berthiaume, Todd Bittner, Ljubomir Perković, Amber Settle, Janos Simon Jun 2004

Bounding The Firing Synchronization Problem On A Ring, André Berthiaume, Todd Bittner, Ljubomir Perković, Amber Settle, Janos Simon

Amber Settle

In this paper we improve the upper and lower bounds on the complexity of solutions to the firing synchronization problem on a ring. In this variant of the firing synchronization problem the goal is to synchronize a ring of identical finite automata. Initially, all automata are in the same state except for one automaton that is designated as the initiator for the synchronization. The goal is to define the set of states and the transition function for the automata so that all machines enter a special fire state for the first time and simultaneously during the final round of the …


Investigation Of New Chelation Ion Chromatography Procedure To Determine The Surface Composition Of Powdered Metal Oxide Samples In The Solid State., B. Peebles, Michael Setter Jun 2004

Investigation Of New Chelation Ion Chromatography Procedure To Determine The Surface Composition Of Powdered Metal Oxide Samples In The Solid State., B. Peebles, Michael Setter

Michael P. Setter

Numerous tests have been conducted on the feasibility of characterizing the surfaces of metal oxide powders using HPLC. An in-line filter housing was modified to serve as a sample chamber to replace the sample loop. A gradient pump was used to gradually increase eluent acidity to find the conditions at which the surface of a metal oxide powder began to dissolve. The theoretical masses of surface monolayers of metal oxide powders were compared with the experimentally determined masses of dissolved material thought to be from the surface to test whether surface and bulk dissolution phenomena in acidic conditions are separable …


Waiting To Inhale: The Demographics Of Toxic Air Release Facilities In 21st-Century California, Manuel Pastor, James Sadd, Rachel Morello-Frosch May 2004

Waiting To Inhale: The Demographics Of Toxic Air Release Facilities In 21st-Century California, Manuel Pastor, James Sadd, Rachel Morello-Frosch

James Sadd

We examine the spatial distribution of toxic air releases and residential demographics in California using 2000 Census data and coeval information from the Federal Toxic Release Inventory for evidence of disproportionate exposure. Methods. We use spatial analysis using GIS, and multivariate regression analysis, including ordered and multinomial logit regressions, in our study. Results. Analytical results suggest a pattern of disproportionate exposure based on race, with the disparity most severe for Latinos, which holds in a series of multivariate regressions, including attempts to test for varying levels of pollution risk and to control for spatial dependence. Conclusions. The study corroborates earlier …


Application Of Fuzzy Logic To System Reliability, Invited Paper, Caroline Lubert May 2004

Application Of Fuzzy Logic To System Reliability, Invited Paper, Caroline Lubert

Caroline P Lubert

No abstract provided.


Relationships Between Computer Skills And Technostress Levels: How Does This Affect Me?, Sonya Shepherd May 2004

Relationships Between Computer Skills And Technostress Levels: How Does This Affect Me?, Sonya Shepherd

Sonya S. Gaither

No abstract provided.


A Dunking Bird Of The Second Kind, Nadine Abraham, Peter Palffy-Muhoray May 2004

A Dunking Bird Of The Second Kind, Nadine Abraham, Peter Palffy-Muhoray

Peter Palffy-Muhoray

The conventional dunking bird is a heat engine that relies on the temperature difference between the head and the tail of the bird for its operation. We describe a new type of dunking bird that is not a heat engine, but one that directly uses the chemical potential difference between liquid water and its vapor.


Drafting A Career In Sports: Determining Underclassmen College Players’ Stock In The Nba Draft, Byron J. Gajewski, Todd Bishop May 2004

Drafting A Career In Sports: Determining Underclassmen College Players’ Stock In The Nba Draft, Byron J. Gajewski, Todd Bishop

Byron J Gajewski

No abstract provided.


Rotational Analysis Of Ftir Spectra From Cigarette Smoke.Pdf, Alan Ford, William A. Burns, Scott Reeve May 2004

Rotational Analysis Of Ftir Spectra From Cigarette Smoke.Pdf, Alan Ford, William A. Burns, Scott Reeve

Scott Reeve

No abstract provided.


Food Based Approaches For A Healthy Nutrition In Africa, Mamoudou Hama Dicko May 2004

Food Based Approaches For A Healthy Nutrition In Africa, Mamoudou Hama Dicko

Pr. Mamoudou H. DICKO, PhD

The latest estimates of the FAO demonstrate the problems of the fight against hunger. These problems are manifested by the ever-increasing number of chronically undernourished people worldwide. Their numbers during the 1999-2001 period were estimated at about 840 million of which 798 million live in developing countries. Sub-Saharan Africa alone represented 198 million of those. In this part of Africa the prevalence of undernourishment ranges from 5-34%, causing growth retardation and insufficient weight gain among one third of the children under five years of age and resulting in a mortality of 5-15% among these children. Malnutrition resulting from undernourishment is …


Studies Toward Understanding The Relationship Between Molecular Structure And Macroscopic Properties Of Interfaces, Mark Anderson May 2004

Studies Toward Understanding The Relationship Between Molecular Structure And Macroscopic Properties Of Interfaces, Mark Anderson

Mark R. Anderson

No abstract is currently available.


Optimization Of Protocrystalline Silicon P-Type Layers For Amorphous Silicon N-I-P Solar Cells, G. M. Ferreira, Chi Chen, R. J. Koval, Joshua M. Pearce, C. R. Wronski, R. W. Collins May 2004

Optimization Of Protocrystalline Silicon P-Type Layers For Amorphous Silicon N-I-P Solar Cells, G. M. Ferreira, Chi Chen, R. J. Koval, Joshua M. Pearce, C. R. Wronski, R. W. Collins

Joshua M. Pearce

Real time spectroscopic ellipsometry has been applied to develop deposition phase diagrams for p-type hydrogenated silicon (Si:H) films prepared at low temperature (200 °C) by rf plasma-enhanced chemical vapor deposition using gas mixtures of SiH4, H2, and BF3. These diagrams depict the regimes of accumulated thickness and H2-dilution ratio R=[H2]/[SiH4] within which p-type amorphous Si:H [a-Si:H], mixed-phase Si:H [(a + μc)-Si:H], and single-phase microcrystalline Si:H [μc-Si:H] films are obtained in depositions on R=0 a-Si:H surfaces. The performance of n–i–p solar cells incorporating p-layers deposited under the same conditions as those used in the phase diagram development has been correlated with …


Application Of A Mickens Finite-Difference Scheme To The Cylindrical Bratu-Gelfand Problem, Ron Buckmire Apr 2004

Application Of A Mickens Finite-Difference Scheme To The Cylindrical Bratu-Gelfand Problem, Ron Buckmire

Ron Buckmire

No abstract provided.


Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk Apr 2004

Prediction Of Radiation Pneumonitis By Dose-Volume Histogram Parameters In Lung Cancer--A Systematic Review, George Rodrigues, Michael Lock, David D'Souza, Edward Yu, Jake Van Dyk

Edward Yu

BACKGROUND AND PURPOSE: To perform a systematic review of the predictive ability of various dose-volume histogram (DVH) parameters (V(dose), mean lung dose (MLD), and normal tissue complication probability (NTCP)) in the incidence of radiation pneumonitis (RP) caused by external-beam radiation therapy. METHODS AND MATERIALS: Studies assessing the relationship between CT-based DVH reduction parameters and RP rate in radically treated lung cancer were eligible for the review. Synonyms for RP, lung cancer, DVH and its associated parameters (NTCP, V(20), V(30), MLD) were combined in a search strategy involving electronic databases, secondary reference searching, and consultation with experts. Individual or group data …


What Makes The Trades?, Christopher Roman Apr 2004

What Makes The Trades?, Christopher Roman

Christopher N. Roman

Article that appeared in Sail magazine (ISSN: 0036-2700).


Lattice Thermal Conductivity Of K2(Bi1_Zsbz)8se13 Solid Solutions, Jeffrey S. Dyck, Theodora Kyratsi, Evripides Hatzikraniotis, M Paraskevopoulous, H. K. Shin, Ctirad Uher, Mercouri Kanatzidis Apr 2004

Lattice Thermal Conductivity Of K2(Bi1_Zsbz)8se13 Solid Solutions, Jeffrey S. Dyck, Theodora Kyratsi, Evripides Hatzikraniotis, M Paraskevopoulous, H. K. Shin, Ctirad Uher, Mercouri Kanatzidis

Jeffrey Dyck

The family of solid solutions of the type B -K2(Bi1_zSbz)8Se13 (0


Liquid Crystal Blazed Gratings Formed In A Single-Step Through Photo-Induced Localization Of Polymer Into A Prismatic Structure, Sang Hwa Kim, Liang-Chy Chien Apr 2004

Liquid Crystal Blazed Gratings Formed In A Single-Step Through Photo-Induced Localization Of Polymer Into A Prismatic Structure, Sang Hwa Kim, Liang-Chy Chien

Sang Kim

A liquid crystal blazed grating having a prismatic polymer microstructure has been developed. The polymer structure is fabricated by photo-induced localization and polymerization of a small concentration of monomer onto one substrate of an electro-optical cell by using ultraviolet light irradiation at 45degrees direction from normal incident. Using this method a periodical one-dimensional pattern with a prismatic shape of polymer can be formed on a one-dimensional pattern-forming state of a cholesteric host. The optical diffraction properties of the grating are evaluated by the application of electric field and light incident angles.


Liquid Crystal Blazed Gratings Formed In A Single-Step Through Photo-Induced Localization Of Polymer Into A Prismatic Structure, Sang Hwa Kim, Liang-Chy Chien Apr 2004

Liquid Crystal Blazed Gratings Formed In A Single-Step Through Photo-Induced Localization Of Polymer Into A Prismatic Structure, Sang Hwa Kim, Liang-Chy Chien

Liang-Chy Chien

A liquid crystal blazed grating having a prismatic polymer microstructure has been developed. The polymer structure is fabricated by photo-induced localization and polymerization of a small concentration of monomer onto one substrate of an electro-optical cell by using ultraviolet light irradiation at 45degrees direction from normal incident. Using this method a periodical one-dimensional pattern with a prismatic shape of polymer can be formed on a one-dimensional pattern-forming state of a cholesteric host. The optical diffraction properties of the grating are evaluated by the application of electric field and light incident angles.


Conduction Band Splitting And Transport Properties Of Bi2se3., J. Navrátil, J. Horák, T. Plecháček, S. Kamba, P. LošŤÁK, Jeffrey Dyck, W. Chen, C. Uher Mar 2004

Conduction Band Splitting And Transport Properties Of Bi2se3., J. Navrátil, J. Horák, T. Plecháček, S. Kamba, P. LošŤÁK, Jeffrey Dyck, W. Chen, C. Uher

Jeffrey Dyck

Detailed transport studies of single crystals of Bi2Se3 were made in the temperature range of 2–300K, and the data were analyzed in terms of a model consisting of two groups of electrons—a centrosymmetrical lower conduction band and an upper conduction band located away from the Γ-point. Very good agreement with the experimental data is obtained assuming the electrons are scattered on acoustic phonons and ionized impurities. A rather strong influence of the latter mechanism is attributed to a large number of charged selenium vacancies in Bi2Se3. The fitted transport parameters were used to calculate the electronic portion of the thermal …


Local Community Participation In Livelihoods Improvement And Sustainability “Anaqeed Al-Khair Project Case Study, Raed Al-Tabini, I.A. Hawamdeh Mar 2004

Local Community Participation In Livelihoods Improvement And Sustainability “Anaqeed Al-Khair Project Case Study, Raed Al-Tabini, I.A. Hawamdeh

Raed Al-Tabini

No abstract provided.


Interacting Near-Solutions To A Hamiltonian System, Gregory S. Spradlin Mar 2004

Interacting Near-Solutions To A Hamiltonian System, Gregory S. Spradlin

Gregory S. Spradlin

A Hamiltonian system with a superquadratic potential is examined. The system is asymptotic to an autonomous system. The difference between the Hamiltonian system and the “problem at infinity,” the autonomous system, may be large, but decays exponientially. The existence of a nontrivial solution homoclinic to zero is proven. Many results of this type rely on a monotonicity condition on the nonlinearity, not assumed here, which makes the problem resemble in some sense the special case of homogeneous (power) nonlinearity. The proof employs variational, minimax arguments. In some similar results requiring the monotonicity condition, solutions inhabit a manifold homeomorphic to the …


Towards Increasing Web Application Productivity, Jia Zhang, Jen-Yao Chung, Carl Chang Feb 2004

Towards Increasing Web Application Productivity, Jia Zhang, Jen-Yao Chung, Carl Chang

Jia Zhang

No abstract provided.


Migration To Web Services Oriented Architecture – A Case Study, Jia Zhang, Jen-Yao Chung, Carl Chang Feb 2004

Migration To Web Services Oriented Architecture – A Case Study, Jia Zhang, Jen-Yao Chung, Carl Chang

Jia Zhang

No abstract provided.


Tools And Strategies For Processing Diffusion-Ordered 2d Nmr Spectroscopy (Dosy) Of A Broad, Featureless Resonance: An Application To Methylaluminoxane (Mao), Jan Lasse Eilertsen, Randall W. Hall, Larry S. Simeral, Leslie G. Butler Feb 2004

Tools And Strategies For Processing Diffusion-Ordered 2d Nmr Spectroscopy (Dosy) Of A Broad, Featureless Resonance: An Application To Methylaluminoxane (Mao), Jan Lasse Eilertsen, Randall W. Hall, Larry S. Simeral, Leslie G. Butler

Randall W. Hall

DOSY has been extremely successful in many studies of molecular weight distributions, especially when the components are separable along the chemical shift axis. However, an unresolved NMR resonance yields the familiar problem of overlapping exponential decays. In a study of methylaluminoxane (MAO), a set of data processing and simulation tools were developed: read Bruker data files (Matlab); preliminary non-linear least-squares fit with f-test (Matlab); movie generation of the fits (Matlab); conversion of diffusion coefficients to molecular masses through molecular volumes (Gaussian-98); and simulation of DOSY data sets for various molecular mass distributions (Mathematica). These tools are presented here and briefly …