Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Faculty Publications

Discipline
Institution
Keyword
Publication Year
File Type

Articles 12151 - 12180 of 14926

Full-Text Articles in Entire DC Network

Transmission Of Mycobacterium Tuberculosis Associated With Failed Completion Of Treatment For Latent Tuberculosis Infection - Chickasaw County, Mississippi, June 1999-March 2002, T. Chamblee, D. Hartley, M. Holcombe, K. Parham, P. Upchurch, R. M. Webb, Alyssa G. Robillard, L. Diem, B. Metchock, N. Deluca, P. D. Mcelroy, T. Navin, W. Walton, P. K. Dewan Mar 2003

Transmission Of Mycobacterium Tuberculosis Associated With Failed Completion Of Treatment For Latent Tuberculosis Infection - Chickasaw County, Mississippi, June 1999-March 2002, T. Chamblee, D. Hartley, M. Holcombe, K. Parham, P. Upchurch, R. M. Webb, Alyssa G. Robillard, L. Diem, B. Metchock, N. Deluca, P. D. Mcelroy, T. Navin, W. Walton, P. K. Dewan

Faculty Publications

During June 1999-March 2002, a total of 16 tuberculosis (TB) cases were reported from Chickasaw County, Mississippi (2000 population: 19,440), corresponding to annual TB incidences of 20.5-27.6 cases per 100,000 population. In comparison, annual TB incidences for Mississippi during the same period decreased from 7.8 to 5.4 cases per 100,000 population. This report summarizes the results of an investigation of the patients and their contacts and demonstrates the need for strategies to increase the proportion of infection contacts that successfully complete treatment for latent TB infection (LTBI).

Go to article

Inverse Multiplexing In Short-Range Multi-Transport Wireless Communications, Lichen Dai, Heidi R. Duffin, James C. Funk, Charles D. Knutson Mar 2003

Inverse Multiplexing In Short-Range Multi-Transport Wireless Communications, Lichen Dai, Heidi R. Duffin, James C. Funk, Charles D. Knutson

Faculty Publications

This paper describes a mechanism for utilizing Inverse Multiplexing to significantly increase the bandwidth available to short-range wireless devices. Previous work with Inverse Multiplexing has focused on wired networks; its implementation with short-range wireless transports introduces heterogeneity in the links, which must be taken into account. A mathematical model for an Inverse Multiplexing system is derived for several scheduling algorithms. Both Process Limited and Transport Limited systems are examined. The validity of this model is shown by our implementation of an Inverse Multiplexing layer that uses IrDA and Bluetooth transports. Concepts related to Inverse Multiplexing such as usage models, negotiation, …

Go to article

Transport Discovery In Wireless Multi-Transport Environments, Shannon B. Barnes, Charles D. Knutson, Ryan W. Woodings Mar 2003

Transport Discovery In Wireless Multi-Transport Environments, Shannon B. Barnes, Charles D. Knutson, Ryan W. Woodings

Faculty Publications

In order to utilize multiple transports, devices must discover common mechanisms for communication, a procedure we call Multi-Transport Discovery. The Multi-Transport Discovery algorithm presented in this paper is a four-phase procedure (Transport Probing, Transport Querying, Address-to-Device Mapping, and Transport Accessibility) that can discover common transports within a multi-transport environment. Transport Probing uses a transport-dependent device discovery mechanism to discover an initial link. Transport Querying communicates over the probed link to query additional transports. Address-to-Device Mapping correctly correlates each transport to a remote device. Finally, Transport Accessibility periodically ascertains link availability during an application session.

Go to article

Gaussian And Mean Curvatures Of Rational Bézier Patches, Thomas W. Sederberg, Jianmin Zheng Mar 2003

Gaussian And Mean Curvatures Of Rational Bézier Patches, Thomas W. Sederberg, Jianmin Zheng

Faculty Publications

This note derives formulae for Gaussian and mean curvatures for tensor-product and triangular rational Bézier patches in terms of the respective control meshes. These formulae provide more geometric intuition than the generic formulae from differential geometry.

Go to article

Density Of States Simulations Of Proteins, Nitin Rathore, Thomas A. Knotts Iv, Juan J. De Pablo Mar 2003

Density Of States Simulations Of Proteins, Nitin Rathore, Thomas A. Knotts Iv, Juan J. De Pablo

Faculty Publications

A modified version of a recently introduced algorithm that calculates density of states by performing a random walk in energy space has been proposed and implemented to study protein folding in a continuum. A united atom representation and the CHARMM19 [B. R. Brooks, R. E. Bruccoleri, B. D. Olafson, D. J. States, S. Swaminathan, and M. Karplus, J. Comput. Chem. 4, 187 (1983)] force field are employed for these simulations. This method permits estimation of the density of states of a protein via a random walk in the energy space, thereby allowing the system to escape from local free-energy minima …

Go to article

An Advanced Ambiguity Selection Algorithm For Seawinds, David G. Long, David W. Draper Mar 2003

An Advanced Ambiguity Selection Algorithm For Seawinds, David G. Long, David W. Draper

Faculty Publications

SeaWinds on QuikSCAT, a spaceborne Ku-band scatterometer, estimates ocean winds via the relationship between the normalized radar backscatter and the vector wind. Scatterometer wind retrieval generates several possible wind vector solutions or ambiguities at each resolution cell, requiring a separate ambiguity selection step to give a unique solution. In processing SeaWinds on QuikSCAT data, the ambiguity selection is "nudged" or initialized using numerical weather prediction winds. We describe a sophisticated new ambiguity selection approach developed at Brigham Young University (BYU) that does not require nudging. The BYU method utilizes a low-order data-driven Karhunen-Loeve wind field model to promote self-consistency. Ambiguity …

Go to article

Experimental Characterization Of The Mimo Wireless Channel: Data Acquisition, Analysis, And Modeling, Michael A. Jensen, Jon W. Wallace, A. Lee Swindlehurst, Brian D. Jeffs Mar 2003

Experimental Characterization Of The Mimo Wireless Channel: Data Acquisition, Analysis, And Modeling, Michael A. Jensen, Jon W. Wallace, A. Lee Swindlehurst, Brian D. Jeffs

Faculty Publications

Detailed performance assessment of space-time coding algorithms in realistic channels is critically dependent upon accurate knowledge of the wireless channel spatial characteristics. This paper presents an experimental measurement platform capable of providing the narrowband channel transfer matrix for wireless communications scenarios. The system is used to directly measure key multiple-input-multiple-output parameters in an indoor environment at 2.45 GHz. Linear antenna arrays of different sizes and construction with up to ten elements at transmit and receive are utilized in the measurement campaign. This data is analyzed to reveal channel properties such as transfer matrix element statistical distributions and temporal and spatial …

Go to article

High-Resolution Measurements With A Spaceborne Pencil-Beam Scatterometer Using Combined Range/Doppler Discrimination Techniques, David G. Long, Michael W. Spencer, Wu-Yang Tsai Mar 2003

High-Resolution Measurements With A Spaceborne Pencil-Beam Scatterometer Using Combined Range/Doppler Discrimination Techniques, David G. Long, Michael W. Spencer, Wu-Yang Tsai

Faculty Publications

Conically scanning pencil-beam scatterometer systems, such as the SeaWinds radar, constitute an important class of instruments for spaceborne climate observation. In addition to ocean winds, scatterometer data are being applied to a wide range of land and cryospheric applications. A key issue for future scatterometer missions is improved spatial resolution. Pencil-beam scatterometers to date have been real-aperture systems where only range discrimination is used, resulting in a relatively coarse resolution of approximately 25 km. In this paper, the addition of Doppler discrimination techniques is proposed to meet the need for higher resolution. The unique issues associated with the simultaneous application …

Go to article

Advances In Experimental Method And Analysis For Estimation Of Geometrically-Necessary Dislocations, Brent L. Adams, Bassem S. El-Dasher, Anthony D. Rollett Mar 2003

Advances In Experimental Method And Analysis For Estimation Of Geometrically-Necessary Dislocations, Brent L. Adams, Bassem S. El-Dasher, Anthony D. Rollett

Faculty Publications

The authors wish to thank The Alcoa Technical Research Center for supplying the specimens and performing the compression tests. This work was supported by the MRSEC program of the National Science Foundation under DMR-0079996 as well as Lawrence Livermore Laboratory DOE/DoD Joint Program. An behavior of grain boundaries of the polycrystalline materials over a wide range of length scales during plastic deformation is considered. Electron backscattering diffraction and orientation imaging microscopy provide automated scanning measurements of the lattice orientation near grain boundaries. These methods are useful to set the necessary length scales. The data are presented for directionally-solidified pure Al …

Go to article

A Joint Trajectory Generator For Motion Recovery, Edward Red, Wei Li Mar 2003

A Joint Trajectory Generator For Motion Recovery, Edward Red, Wei Li

Faculty Publications

This paper describes an adaptive S-curve used to recover a tool path upon a system crash in the Windows operating system (OS). For a mechanism such as a robot or machine tool, the joint values, being delivered as setpoints to the servo-controller, are dynamically recorded by the real-time operating system also residing on the computer. The real-time OS can control the abort and record pertinent motion data after Windows OS crash.

Go to article

What The Universe Means To People Like Me, David D. Allred Mar 2003

What The Universe Means To People Like Me, David D. Allred

Faculty Publications

When I picked up David's paper to read it, I had a pencil in my hand. Years of reading my students' and my own papers made it natural to edit as I read. However, I heard in my mind the voice of my mother advising me to put the pencil down. This wasn't time to edit but to hear and understand. Still, I kept the pencil in my hand for the first few pages and made a few notes before I put it down and just read. I could hear David's voice speaking the words I read. It was good …

Go to article

Fuel Characteristics Of Processed, High-Fiber Sugarcane, Scott Q. Turn, Charles M. Kinoshita, Lee A. Jakeway, Bryan M. Jenkins, Larry Lin Baxter 8507091, Ben C. Wu, Linda G. Blevins Feb 2003

Fuel Characteristics Of Processed, High-Fiber Sugarcane, Scott Q. Turn, Charles M. Kinoshita, Lee A. Jakeway, Bryan M. Jenkins, Larry Lin Baxter 8507091, Ben C. Wu, Linda G. Blevins

Faculty Publications

A study of treatment methods to improve the fuel characteristics of sugarcane variety B52298 was conducted. Two parent materials, whole cane (WC) and stripped cane (SC), were included in the study. The whole cane material was subjected to three treatments: (1) no treatment, WC-U; (2) a single milling, WC-M; and (3) an initial milling followed by leaching and a secondary milling, WC-MLM. Treatments (1) through (3) are in order of increasing severity. The stripped cane material was subjected to treatment (3) and designated as SC-MLM. Regardless of parent material, milling produced moisture contents of ∼50% wet basis and fiber bulk …

Go to article

Neutral-Plasma Oscillations At Zero Temperature, Scott D. Bergeson, Ross L. Spencer Feb 2003

Neutral-Plasma Oscillations At Zero Temperature, Scott D. Bergeson, Ross L. Spencer

Faculty Publications

Cold plasma theory is used to calculate the response of an ultracold neutral plasma to an applied rf field. The free oscillation of the system has a continuous spectrum and an associated damped quasimode. This quasimode dominates the driven response and is resonant in the tail of the density distribution. Recent experiments used the plasma response to an applied rf field to determine the plasma density in an expanding ultracold plasma. The comparison between experiment and theory indicates that this method accurately determines the expansion velocity and underestimates the initial plasma density by a factor of 3 in weakly collisional …

Go to article

Algan/Gan Heterostructure Field-Effect Transistors On Single-Crystal Bulk Aln, X. Hu, J. Deng, N. Pala, R. Gaska, M. S. Shur, C. Q. Chen, J. Yang, Grigory Simin, M. A. Khan, J. C. Rojo, L. J. Schowalter Feb 2003

Algan/Gan Heterostructure Field-Effect Transistors On Single-Crystal Bulk Aln, X. Hu, J. Deng, N. Pala, R. Gaska, M. S. Shur, C. Q. Chen, J. Yang, Grigory Simin, M. A. Khan, J. C. Rojo, L. J. Schowalter

Faculty Publications

We report on the performance of AlGaN/GaN/AlN heterostructurefield-effect transistors(HFETs) grown over slightly-off c-axis, single-crystal, bulk AlN substrates. Dc and rf characteristics of these devices were comparable to HFETs grown on semi-insulating SiC. The obtained results demonstrate that bulk AlN substrates are suitable for fabricating high-power microwave AlGaN/GaN transistors.

Go to article

Semiclassical Dynamics With Quantum Trajectories: Formulation And Comparison With The Semiclassical Initial Value Representation Propagator, Sophya Garashchuk, Vitaly A. Rassolov Feb 2003

Semiclassical Dynamics With Quantum Trajectories: Formulation And Comparison With The Semiclassical Initial Value Representation Propagator, Sophya Garashchuk, Vitaly A. Rassolov

Faculty Publications

We present a time-dependent semiclassical method based on quantum trajectories. Quantum-mechanical effects are described via the quantum potential computed from the wave function density approximated as a linear combination of Gaussian fitting functions. The number of the fitting functions determines the accuracy of the approximate quantum potential (AQP). One Gaussian fit reproduces time-evolution of a Gaussian wave packet in a parabolic potential. The limit of the large number of fitting Gaussians and trajectories gives the full quantum-mechanical result. The method is systematically improvable from classical to fully quantum. The fitting procedure is implemented as a gradient minimization. We also compare …

Go to article

Chemomechanical Surface Patterning And Functionalization Of Silicon Surfaces Using An Atomic Force Microscope, Brent A. Wascaser, Michael J. Maughan, Travis L. Niederhauser, Matthew R. Linford, Robert C. Davis, Ian A. Mowat Feb 2003

Chemomechanical Surface Patterning And Functionalization Of Silicon Surfaces Using An Atomic Force Microscope, Brent A. Wascaser, Michael J. Maughan, Travis L. Niederhauser, Matthew R. Linford, Robert C. Davis, Ian A. Mowat

Faculty Publications

Surface modification and patterning at the nanoscale is a frontier in science with significant possible applications in biomedical technology and nanoelectronics. Here we show that an atomic force microscope (AFM) can be employed to simultaneously pattern and functionalize hydrogen-terminated silicon (111) surfaces. The AFM probe was used to break Si-H and Si-Si bonds in the presence of reactive molecules, which covalently bonded to the scribed Si surface. Functionalized patches and patterned lines of molecules were produced. Linewidths down to 30 nm were made by varying the force at the tip

Go to article

The James Willard Oliver Collection Of David Hume & Eighteenth-Century Philosophy, Patrick G. Scott Feb 2003

The James Willard Oliver Collection Of David Hume & Eighteenth-Century Philosophy, Patrick G. Scott

Faculty Publications

Describes a collection of first and other editions of the Scottish philosopher David Hume, recently donated to the University of South Carolina by Prof. James Willard Oliver, and uses older library records from the library of South Carolina College (founded in 1801) to chart the changing reputation and influence of Hume's philosophical works as compared to his essays and historical writings. First presented at the SE American Society for Eighteenth-Century Studies, in Columbia, SC, February 3003.

Go to article

Onset Of Major Depressive Disorder Among Adolescents, John P. Hoffmann, Scott A. Baldwin, Felicia G. Cerbone Feb 2003

Onset Of Major Depressive Disorder Among Adolescents, John P. Hoffmann, Scott A. Baldwin, Felicia G. Cerbone

Faculty Publications

Objectives: To examine the association between parental affective disorders and psychoactive substance use disor- ders and the onset of major depressive disorder (MDD) among adolescents and young adults and to determine whether this association is affected by stressful life events, family cohesion, self-esteem, or gender. Method: Prospective cohort study of 804 adolescents, aged 11–17 years, and their parents who were followed for seven consecutive years. The sam- ple was drawn from the Minneapolis-St. Paul metropolitan area. Parental diagnoses were based on Structured Clinical Interview for DSM-III-R administered during study screening stage. Diagnoses of MDD and age of onset were based …

Go to article

Real Time Dynamic Trajectory Smoothing For Uninhabited Aerial Vehicles, Erik Anderson, Randal Beard, Timothy W. Mclain Feb 2003

Real Time Dynamic Trajectory Smoothing For Uninhabited Aerial Vehicles, Erik Anderson, Randal Beard, Timothy W. Mclain

Faculty Publications

Sponsorship: AFOSR, DARPA. This paper presents a real-time, feasible trajectory generation algorithm for unmanned air vehicles (UAVs) flying through a sequence of waypoints. The algorithm produces extremal trajectories that transition between straight-line path segments in a time-optimal fashion. In addition, the algorithm can be configured so that the dynamically feasible trajectory has the same path length as the straight-line waypoint path. Implementation issues associated with the algorithm are described in detail. Simulation studies show the effectiveness of the proposed method.

Go to article

Sunni Modernist Theories Of Social Contract In Contemporary Egypt, Shahrough Akhavi Feb 2003

Sunni Modernist Theories Of Social Contract In Contemporary Egypt, Shahrough Akhavi

Faculty Publications

No abstract provided.

Go to article

Becoming A Subject: Political Prisoners During The Greek Civil War, By Polymeris Voglis, Gerasimos Augustinos Feb 2003

Becoming A Subject: Political Prisoners During The Greek Civil War, By Polymeris Voglis, Gerasimos Augustinos

Faculty Publications

Reviews the non-fiction book Becoming a Subject: Political Prisoners During the Greek Civil War, by Polymeris Voglis.

Go to article

On Extraction From Nps, William D. Davies, Stanley William Dubinsky Feb 2003

On Extraction From Nps, William D. Davies, Stanley William Dubinsky

Faculty Publications

This paper sheds new light on the conditions governing extraction from NPs. A close examination of wh-extraction out of object NPs reveals that previously unnoticed semantic factors play a greater role than has been recognized. In particular, we find that NPs lacking 'participant' structure do not permit wh-extraction at all, and that certain NPs permit extraction even when they are definite. At the same time, the prohibition on wh-extraction from subject NPs is shown to be a purely syntactic phenomenon which arises from the particular way in which the Extended Projection Principle is satisfied in English.

Go to article

Algan/Gan Hemts - Operation In The K-Band And Above, Ioulia P. Smorchkova, M. Wojtowicz, Rajinder Sandhu, R. Tsai, M. Barsky, C. Namba, P.-S. Liu, R. Dia, Minhdao Truong, D. Ko, J. Wang, H. Wange, Asif Khan Feb 2003

Algan/Gan Hemts - Operation In The K-Band And Above, Ioulia P. Smorchkova, M. Wojtowicz, Rajinder Sandhu, R. Tsai, M. Barsky, C. Namba, P.-S. Liu, R. Dia, Minhdao Truong, D. Ko, J. Wang, H. Wange, Asif Khan

Faculty Publications

We report on the power and microwave noise performance of AlGan/GaN high electron-mobility transistors (HEMTs) at frequencies f > 18 GHz (K- and Ka-bands). At 20 GHz, a record continuous-wave output power of 1.6 W has been achieved on an eight-finger 500-mum total gate-periphery device. At 29 GHz, a 120-mum gate-periphery device showed a pulsed output density of 1.6 W/mm with an associated gain of 6.7 dB and power-added efficiency of 26%. Minimum noise figure of 1.5 dB has been achieved on a 0.2 mum x 200 mum device at 26 GHz. The data demonstrate the viability of AlGan/GaN HEMTs for …

Go to article

Utilization Of Algal And Bacterial Extracellular Polymeric Secretions (Eps) By The Deposit-Feeding Brittlestar Amphipholis Gracillima (Echinodermata), D. L. Hoskins, S. E. Stancyk, Alan W. Decho Feb 2003

Utilization Of Algal And Bacterial Extracellular Polymeric Secretions (Eps) By The Deposit-Feeding Brittlestar Amphipholis Gracillima (Echinodermata), D. L. Hoskins, S. E. Stancyk, Alan W. Decho

Faculty Publications

Like many deposit-feeding organisms, the burrowing brittlestar Amphipholis gracillima feeds on particulate organic matter in surface sediments. Microbial exopolymeric secretions (EPS) are carbohydrate-enriched polymers produced by microalgae and bacteria that bind aggregates and form dense biofilms near the sediment-water interface. EPS are assimilable by some benthic infauna and may be utilized as a significant carbon source. EPS are absorbed by some deposit-feeders, including a holothurian, and may be supplemental sources of nutrition. The burrowing brittlestar A. gracillima is a deposit-feeder that was used in a mass balance approach to model the incorporation of radiolabeled EPS by bottom feeders. Brittlestars were …

Go to article

Comprehensive Model Of Alkali-Salt Deposition In Recovery Boilers, Richard A. Wessel, Larry Lin Baxter 8507091 Feb 2003

Comprehensive Model Of Alkali-Salt Deposition In Recovery Boilers, Richard A. Wessel, Larry Lin Baxter 8507091

Faculty Publications

Algorithms for alkali-salt deposition have been implemented into a comprehensive model for recovery boilers. The model includes (a) mechanisms for particle formation and chemistry, (b) particle deposition and adhesion, and (c) deposit thermal properties. These algorithms are fully coupled with models for turbulent flow, black liquor combustion, and heat transfer in the boiler. Model predictions for particle deposition in the convection pass are presented for a Babcock & Wilcox recovery boiler. This work is part of an ongoing project sponsored by the U.S. Department of Energy to demonstrate an improved ability to anticipate ash behavior with changes in fuel composition, …

Go to article

Every Three-Point Set Is Zero Dimensional, David L. Fearnley, J. W. Lamoreaux, David L. Fearnley Jan 2003

Every Three-Point Set Is Zero Dimensional, David L. Fearnley, J. W. Lamoreaux, David L. Fearnley

Faculty Publications

This paper answers a question of Jan J. Dijkstra by giving a proof that all three-point sets are zero dimensional. It is known that all two-point sets are zero dimensional, and it is known that for all n > 3, there are n-point sets which are not zero dimensional, so this paper answers the question for the last remaining case.

Go to article

Odd Perfect Numbers Have A Prime Factor Exceeding 10^7, Paul M. Jenkins Jan 2003

Odd Perfect Numbers Have A Prime Factor Exceeding 10^7, Paul M. Jenkins

Faculty Publications

It is proved that every odd perfect number is divisible by a prime greater than 10^7.

Go to article

Time-Resolved Electroluminescence Of Algan-Based Light-Emitting Diodes With Emission At 285 Nm, M. Shatalov, A. Chitnis, V. Mandavilli, R. Pachipulusu, J. P. Zhang, V. Adivarahan, S. Wu, Grigory Simin, M. Asif Khan, G. Tamulaitis, A. Sereika, I. Yilmaz, M. S. Shur, R. Gaska Jan 2003

Time-Resolved Electroluminescence Of Algan-Based Light-Emitting Diodes With Emission At 285 Nm, M. Shatalov, A. Chitnis, V. Mandavilli, R. Pachipulusu, J. P. Zhang, V. Adivarahan, S. Wu, Grigory Simin, M. Asif Khan, G. Tamulaitis, A. Sereika, I. Yilmaz, M. S. Shur, R. Gaska

Faculty Publications

We present a study on the time evolution of the electroluminescence(EL)spectra of AlGaN-based deep ultraviolet light-emitting diodes(LEDs) under pulsed current pumping. The ELspectra peaks at 285 nm and 330 nm are found to result from recombination involving band-to-band and free carriers to deep acceptor level transitions. The 330 nm long-wavelength transitions to deep acceptor levels in the p-AlGaN layer as well as the nonradiative processes significantly influence the LED internal quantum efficiency.

Go to article

Paul, Hardships, And Suffering, David E. Fredrickson Jan 2003

Paul, Hardships, And Suffering, David E. Fredrickson

Faculty Publications

No abstract provided.

Go to article

North American Lutheranism And The New Ethnics, Mark A. Granquist Jan 2003

North American Lutheranism And The New Ethnics, Mark A. Granquist

Faculty Publications

No abstract provided.

Go to article

First Prev Next Last