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2003

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Articles 481 - 510 of 3372

Full-Text Articles in Physical Sciences and Mathematics

Mobicom Poster: Evaluating Location Predictors With Extensive Wi-Fi Mobility Data, Libo Song, David Kotz, Ravi Jain, Xiaoning He Oct 2003

Mobicom Poster: Evaluating Location Predictors With Extensive Wi-Fi Mobility Data, Libo Song, David Kotz, Ravi Jain, Xiaoning He

Dartmouth Scholarship

A fundamental problem in mobile computing and wireless networks is the ability to track and predict the location of mobile devices. An accurate location predictor can significantly improve the performance or reliability of wireless network protocols, the wireless network infrastructure itself, and many applications in pervasive computing. These improvements lead to a better user experience, to a more cost-effective infrastructure, or both. Location prediction has been proposed in many areas of wireless cellular networks as a means of enhancing performance, including better mobility management, improved assignment of cells to location areas, more efficient paging, and call admission control. To the …


Reflections On Apollo, Eugene A. Cernan Oct 2003

Reflections On Apollo, Eugene A. Cernan

IMSA Great Minds Program ®

During 20 years as a Naval Aviator, including 13 years with the National Aeronautics and Space Administration (NASA), Captain Eugene A. Cernan left his mark on history with three historic missions in space as the Pilot of Gemini IX (1966), the Lunar Module Pilot of Apollo X (1969), and the Commander of Apollo XVII (1972). After flying to the moon not once, but twice, he also holds the distinction of being the second American to walk in space and the last man to have left his footprints on the lunar surface.

Captain Cernan received a Bachelor of Science degree in …


Scwds Briefs: Volume 19, Number 3 (October 2003) Oct 2003

Scwds Briefs: Volume 19, Number 3 (October 2003)

Southeastern Cooperative Wildlife Disease Study: Publications


• Johne's Disease and Southeastern White-tailed Deer: Paratuberculosis or Johne's disease, caused by the bacterium Mycobacterium avium subspecies paratuberculosis (Mptb), occurs worldwide and is recognized as a significant health problem for domestic ruminants, wild ruminants in zoological collections, and farmed cervids. SCWDS recently completed a culture and serologic survey for Mptb infection among white-tailed deer populations in the southeastern United States.
• SCWDS has been involved in exotic tick research and surveillance throughout the United States and the Caribbean region for over 25 years, and surveillance efforts now are being expanded in the southeastern United States and Puerto Rico. One …


A Novel Behavior Observed In Humpback Whales On Wintering Grounds At Abrolhos Bank (Brazil), Maria Morete, Ana Freitas, Marcia Engel, Richard M. Pace Iii, Phillip Clapham Oct 2003

A Novel Behavior Observed In Humpback Whales On Wintering Grounds At Abrolhos Bank (Brazil), Maria Morete, Ana Freitas, Marcia Engel, Richard M. Pace Iii, Phillip Clapham

United States Department of Commerce: Staff Publications

We describe a novel behavior, termed “tail-up,” observed in humpback whales (Megaptera novaeangliae) on wintering grounds on Abrolhos Bank, Brazil. The behavior involves the whale positioned vertically in the water column with its tail in the air. Wirh the exception of calves, tail-up was observed in all social classes, and its frequency increased through the end of the season. Tail-ups were recorded in 144 (5.8%) of 2,465 groups of whales observed from a shore station, and in 297 (14.9%) of 1,996 groups observed from vessel surveys; biases in each method suggest that the true frequency lies between these …


Multi-Agent Coalition Via Autonomous Price Negotiation In A Real-Time Web Environment, Hoong Chuin Lau, Wei Sian Lim Oct 2003

Multi-Agent Coalition Via Autonomous Price Negotiation In A Real-Time Web Environment, Hoong Chuin Lau, Wei Sian Lim

Research Collection School Of Computing and Information Systems

In e-marketplaces, customers specify job requests in real-time and agents form coalitions to service them. This paper proposes a protocol for self-interested agents to negotiate prices in forming successful coalitions. We propose and experiment with two negotiation schemes: one allows information sharing while the other does not.


Dirichlet Boundary Control Of Hyperbolic Equations In The Presence Of State Constraints, Boris S. Mordukhovich, Jean-Pierre Raymond Oct 2003

Dirichlet Boundary Control Of Hyperbolic Equations In The Presence Of State Constraints, Boris S. Mordukhovich, Jean-Pierre Raymond

Mathematics Research Reports

We study optimal control problems for hyperbolic equations (focusing on the multidimensional wave equation) with control functions in the Dirichlet boundary conditions under hard/pointwise control and state constraints. Imposing appropriate convexity assumptions on the cost integral functional, we establish the existence of optimal control and derive new necessary optimality conditions in the integral form of the Pontryagin Maximum Principle for hyperbolic state-constrained systems.


On The Nitrogen Vacancy In Gan, David C. Look, Gary C. Farlow, P. J. Drevinsky, D. F. Bliss, J. R. Sizelove Oct 2003

On The Nitrogen Vacancy In Gan, David C. Look, Gary C. Farlow, P. J. Drevinsky, D. F. Bliss, J. R. Sizelove

Physics Faculty Publications

The dominant electrically active defect produced by 0.42 MeV electron irradiation in GaN is a 70 meV donor. Since only N-sublattice displacements can be produced at this energy, and since theory predicts that the N interstitial is a deep acceptor in n-type GaN, we argue that the 70 meV donor is most likely the isolated N vacancy. The background shallow donors, in the 24–26 meV range, actually decrease in concentration, probably due to interactions with mobile N interstitials that are produced by the irradiation. Thus, the recent assignment of a photoluminescence (PL) line as an exciton bound to a …


Seismogenic Zone Structure Of The Southern Middle America Trench, Costa Rica, H. R. Deshon, S. Y. Schwartz, S. L. Bilek, L. M. Dorman, V. Gonzalez, J. M. Protti, E. R. Flueh, Timothy H. Dixon Oct 2003

Seismogenic Zone Structure Of The Southern Middle America Trench, Costa Rica, H. R. Deshon, S. Y. Schwartz, S. L. Bilek, L. M. Dorman, V. Gonzalez, J. M. Protti, E. R. Flueh, Timothy H. Dixon

School of Geosciences Faculty and Staff Publications

The shallow seismogenic portion of subduction zones generates damaging large and great earthquakes. This study provides structural constraints on the seismogenic zone of the Middle America Trench offshore central Costa Rica and insights into the physical and mechanical characteristics controlling seismogenesis. We have located ∼300 events that occurred following the MW 6.9, 20 August 1999, Quepos, Costa Rica, underthrusting earthquake using a three-dimensional velocity model and arrival time data recorded by a temporary local network of land and ocean bottom seismometers. We use aftershock locations to define the geometry and characteristics of the seismogenic zone in this region. These …


Cs 790-01: Introduction To Parallel Algorithms, Natsuhiko Futamura Oct 2003

Cs 790-01: Introduction To Parallel Algorithms, Natsuhiko Futamura

Computer Science & Engineering Syllabi

Low-cost parallel computers such as PC clusters are becoming available, and many previously unsolvable problems can be solved using such computers. However, designing algorithms that perform well on parallel computers is often challenging. The focus of this course is on learning how to design algorithms for parallel computers and how to evaluate them.


ข่าวกิจกรรมสิ่งแวดล้อม Oct 2003

ข่าวกิจกรรมสิ่งแวดล้อม

Thai Environment

No abstract provided.


เทคโนโลยีชีวภาพกับการบำบัดสารเคมีอันตราย (ตอนที่ 1), เอกวัล ลือพร้อมชัย Oct 2003

เทคโนโลยีชีวภาพกับการบำบัดสารเคมีอันตราย (ตอนที่ 1), เอกวัล ลือพร้อมชัย

Thai Environment

No abstract provided.


ความร่วมมือด้านการขนส่งลำน้ำในเอเชียตะวันออกเฉียงใต้, ระหัตร โรจนประดิษฐ์ Oct 2003

ความร่วมมือด้านการขนส่งลำน้ำในเอเชียตะวันออกเฉียงใต้, ระหัตร โรจนประดิษฐ์

Thai Environment

No abstract provided.


การปกป้องอ่าว Aqaba เมือง Eilat, กนกธร ดำรงวัฒน Oct 2003

การปกป้องอ่าว Aqaba เมือง Eilat, กนกธร ดำรงวัฒน

Thai Environment

No abstract provided.


Magnetic Storage Device Using Induced Magnetic Reversal Of A Cobalt, Scott Whittenburg Oct 2003

Magnetic Storage Device Using Induced Magnetic Reversal Of A Cobalt, Scott Whittenburg

Chemistry Faculty Publications

The effects of the applied field, cell size, and cutting area on the ‘‘seed’’ induced magnetic reversal of a cobalt element array have been studied by a stochastic dynamic micromagnetics code using the Laudau–Lifshitz–Gilbert equation. Three magnetic reversal mechanisms under different magnitudes of the applied field have been investigated by examining the energy profiles. To minimize the effect of the thermal fluctuations on the switching time, an applied field with magnitude around 0.7 or 0.8 T and an element array with cutting area less than 10 nm310 nm are required. By using the smaller cellsize, the switching time and the …


สัมภาษณ์ : สภาเครือข่ายเยาวชนสิ่งแวดล้อมแห่งชาติ (Thai Yen), สิริพร แก่นสียา Oct 2003

สัมภาษณ์ : สภาเครือข่ายเยาวชนสิ่งแวดล้อมแห่งชาติ (Thai Yen), สิริพร แก่นสียา

Thai Environment

No abstract provided.


พ.ร.บ. สิ่งบ่งชี้ทางภูมิศาสตร์, สิริพร แก่นสียา Oct 2003

พ.ร.บ. สิ่งบ่งชี้ทางภูมิศาสตร์, สิริพร แก่นสียา

Thai Environment

No abstract provided.


ระบบทะเบียนการปลดปล่อยมลพิษสู่สิ่งแวดล้อม, สุรเชษฐ์ พิทยาพิบูลพงศ์ Oct 2003

ระบบทะเบียนการปลดปล่อยมลพิษสู่สิ่งแวดล้อม, สุรเชษฐ์ พิทยาพิบูลพงศ์

Thai Environment

No abstract provided.


มุมมองการจัดการทรัพยากรธรรมชาติและสิ่งแวดล้อม ในทัศนะของประชาชน, สิริพร แก่นสียา Oct 2003

มุมมองการจัดการทรัพยากรธรรมชาติและสิ่งแวดล้อม ในทัศนะของประชาชน, สิริพร แก่นสียา

Thai Environment

No abstract provided.


สิ่งแวดล้อมน่ารู้ Oct 2003

สิ่งแวดล้อมน่ารู้

Thai Environment

No abstract provided.


Climate: Past, Present, And Future, Saxon E. Sharpe, Rick Forester, Amy J. Smiecinski Oct 2003

Climate: Past, Present, And Future, Saxon E. Sharpe, Rick Forester, Amy J. Smiecinski

Publications (YM)

Climatology and meteorology studies in the Yucca Mountain area have resulted in the following key observations and conclusions: • The present-day arid climate of the Yucca Mountain area can be understood in terms of global-scale atmospheric circulation and regional to-local physiographic features. In general terms, the area is under the influence of mid-latitude westerly winds and associated storm systems during the cool part of the year and and is under the influence of moist air advected from the eastern tropical Pacific Ocean and Gulf of California during the summer. Temperature and precipitation data from Nevada regions 3 and 4 (southern …


Exact Multiplicity For Periodic Solutions Of Duffing Type, Hongbin Chen, Yi Li, Xiaojie Hou Oct 2003

Exact Multiplicity For Periodic Solutions Of Duffing Type, Hongbin Chen, Yi Li, Xiaojie Hou

Mathematics and Statistics Faculty Publications

In this paper, we study the following Duffing-type equation:

x″+cx′+g(t,x)=h(t),

where g(t,x) is a 2π-periodic continuous function in t and concave–convex in x, and h(t) is a small continuous 2π-periodic function. The exact multiplicity and stability of periodic solutions are obtained.


Corner Cases In Value-Based Partial Redundancy Elimination, Thomas Vandrunen, Antony L. Hosking Oct 2003

Corner Cases In Value-Based Partial Redundancy Elimination, Thomas Vandrunen, Antony L. Hosking

Department of Computer Science Technical Reports

No abstract provided.


Single-Walled Carbon Nanotube Bundles Intercalated With Semiconductor Nanoparticles, Manashi Nath, Pallavi V. Teredesai, D. V. S. Muthu, A. K. Sood, Chintamani Nagesa Ramachandra Rao Oct 2003

Single-Walled Carbon Nanotube Bundles Intercalated With Semiconductor Nanoparticles, Manashi Nath, Pallavi V. Teredesai, D. V. S. Muthu, A. K. Sood, Chintamani Nagesa Ramachandra Rao

Chemistry Faculty Research & Creative Works

Nanoparticles of CdSe, CdS and ZnSe have been incorporated in the inter-tubular gaps of single-walled carbon nanotube (SWNT) bundles. Electron microscope, X-ray diffraction (XRD), electronic spectroscopy and Raman studies have been employed to characterize these systems. The lengths of the intercalate inside the bundles could be varied by changing the reaction conditions. Electronic absorption and photoluminescence studies from the semiconductor intercalates show the expected blue-shift with respect to the corresponding bulk samples in CdS and ZnS samples. The SWNT lattice is expanded on incorporating CdSe as confirmed by XRD in the low-angle range. The expansion in the lattice is also …


Toy Models For The Falling Chimney, Gabriele U. Varieschi, Kaoru Kamiya Oct 2003

Toy Models For The Falling Chimney, Gabriele U. Varieschi, Kaoru Kamiya

Physics Faculty Works

In this paper we review the theory of the ‘‘falling chimney,’’ which deals with the breaking in mid-air of tall structures when they fall to the ground. We show that these ruptures can be caused by either shear forces typically developing near the base, or by the bending of the structure which is caused primarily by the internal bending moment. In the latter case the breaking is more likely to occur between one-third and one-half of the height of the chimney. Small scale toy models are used to reproduce the dynamics of the falling chimney. By examining photos taken during …


Extensive Regional Atmospheric Hydrocarbon Pollution In The Southwestern United States, Lambert A. Doezema Oct 2003

Extensive Regional Atmospheric Hydrocarbon Pollution In The Southwestern United States, Lambert A. Doezema

Chemistry and Biochemistry Faculty Works

Light alkane hydrocarbons are present in major quantities in the near-surface atmosphere of Texas, Oklahoma, and Kansas during both autumn and spring seasons. In spring 2002, maximum mixing ratios of ethane [34 parts per 109 by volume (ppbv)], propane (20 ppbv), and n-butane (13 ppbv) were observed in north-central Texas. The elevated alkane mixing ratios are attributed to emissions from the oil and natural gas industry. Measured alkyl nitrate mixing ratios were comparable to urban smog values, indicating active photochemistry in the presence of nitrogen oxides, and therefore with abundant formation of tropospheric ozone. We estimate that 4-6 teragrams of …


Adaptive Parallel Framework Algorithm (Apfa) For Environmental Engineering Applications, Lianghua Zhou Oct 2003

Adaptive Parallel Framework Algorithm (Apfa) For Environmental Engineering Applications, Lianghua Zhou

Civil & Environmental Engineering Theses & Dissertations

This research proposes a new framework methodology for integrating environmental computer applications in flexible, open and adaptively and reusable manners so that the resulting application framework could be used to effectively, flexibly and rapidly handle various environmental problems and issues. Research also demonstrates the framework algorithm with a case study. The proposed algorithm is referred as Adaptive Parallel Framework Algorithm (APF A). Core concept of the APF A is based on a parallelism, "many-to-one" mode to communicate among environmental applications, and takes advantages of a loosely coupled technology that helps archiving the required flexibility, extensibility and usability of integrated systems. …


A Computer-Based Articulation Training Aid For Short Words (Cata), Mukund Devarajan Oct 2003

A Computer-Based Articulation Training Aid For Short Words (Cata), Mukund Devarajan

Electrical & Computer Engineering Theses & Dissertations

Several improvements in the vowel articulation training aid (VATA) are described, as well as the efforts to extend the visual feedback system to operate with short words in the form of consonant, vowel and consonant (CVC). The extended version of the visual feedback system is referred to as CATA (Computer-based Articulation Training Aid); the vowel version of the aid (VATA) only operates with ten American English monopthong vowels. Improvements in VATA include the use of a neural network (NN) recognizer method to prune a large database of vowel recordings to eliminate noisy and/or mispronounced tokens. The spectral jitter problem, previously …


Brownian Dynamics Simulation Studies Of Ion Throughput During Cellular Electroporation, Juan A. Gonzalez-Cuevas Oct 2003

Brownian Dynamics Simulation Studies Of Ion Throughput During Cellular Electroporation, Juan A. Gonzalez-Cuevas

Electrical & Computer Engineering Theses & Dissertations

The purpose of the present research work is to analyze the flow of ions through pores formed in the plasma membrane of biological cells during electroporation. In this regard, simulations have been conducted to track the movement of ions in 3-D space based on a Brownian dynamics model, which is mostly deterministic but has some stochastic properties to account for ionic scattering. From the Brownian dynamics simulations, it has been possible to estimate the pore's conductance as well as transport parameters such as the diffusion coefficient and mobility within the pore region, of which there is no experimental data currently …


Dissolved Humic Substances: Characterization Of Their Sorption Onto Iron Hydroxide Aluminum Hydroxide Kaolinite And Smectite, Sarah E. Diebel Oct 2003

Dissolved Humic Substances: Characterization Of Their Sorption Onto Iron Hydroxide Aluminum Hydroxide Kaolinite And Smectite, Sarah E. Diebel

OES Theses and Dissertations

Humic (HA) and fulvic (FA) acids participate in many geochemical processes and the mechanisms of their sorption to colloidal surfaces are numerous, indicating these substances are complex and heterogeneous. The current study focuses on the interactions of the Fe hydroxide (FE), Al hydroxide, Kaolinite (KA) and Smectite (SM) and these naturally occurring organic acids using Fourier Transform Infrared Spectroscopy (FTIR) and DOC analysis at pH 4. FTIR was used for the initial functional group characterization, as well as the comparison of before and after adsorption spectra of the HA and FA. DOC examined the amounts of HA and FA adsorbed …


การจัดการน้ำเสียในมหาวิทยาลัย, นุชนาถ แช่มช้อย Oct 2003

การจัดการน้ำเสียในมหาวิทยาลัย, นุชนาถ แช่มช้อย

Thai Environment

No abstract provided.