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2001

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Full-Text Articles in Physical Sciences and Mathematics

โครงการมหาวิทยาลัยรวมพลังหารสอง, กรชนก รักษาเสรี, สิริพร แก่นสียา Jul 2001

โครงการมหาวิทยาลัยรวมพลังหารสอง, กรชนก รักษาเสรี, สิริพร แก่นสียา

Thai Environment

No abstract provided.


โครงการฐานข้อมูลสารเคมีอันตรายเพื่อการอ้างอิง, วรพรรณ ด่านอุตรา Jul 2001

โครงการฐานข้อมูลสารเคมีอันตรายเพื่อการอ้างอิง, วรพรรณ ด่านอุตรา

Thai Environment

No abstract provided.


การคัดกรองข้อมูลทางโภชนาการผ่านสื่ออินเตอร์เน็ต, จงจิตร อังคทะวานิช Jul 2001

การคัดกรองข้อมูลทางโภชนาการผ่านสื่ออินเตอร์เน็ต, จงจิตร อังคทะวานิช

Thai Environment

No abstract provided.


ถังขยะในสยามสแควร์, เกศรินทร์ พาราทิพย์เจริญชัย, บุณฑริก มากบุญ Jul 2001

ถังขยะในสยามสแควร์, เกศรินทร์ พาราทิพย์เจริญชัย, บุณฑริก มากบุญ

Thai Environment

No abstract provided.


แนะนำโครงการของสถาบันวิจัยสภาวะแวดล้อม : การศึกษาวิจัยเพื่อสร้างเครื่องมือทางเศรษฐศาสตร์ และเครื่องมือทางสังคมในการประเมินผลการอนุรักษ์พลังงาน, เสถียร รุจิรวนิช Jul 2001

แนะนำโครงการของสถาบันวิจัยสภาวะแวดล้อม : การศึกษาวิจัยเพื่อสร้างเครื่องมือทางเศรษฐศาสตร์ และเครื่องมือทางสังคมในการประเมินผลการอนุรักษ์พลังงาน, เสถียร รุจิรวนิช

Thai Environment

No abstract provided.


Reactivity Of Acyclic (Pentadienyl)Iron(1+) Cations With Weak Carbon Nucleophiles, M. Azad Hossain, Myung-Jong Jin, William Donaldson Jul 2001

Reactivity Of Acyclic (Pentadienyl)Iron(1+) Cations With Weak Carbon Nucleophiles, M. Azad Hossain, Myung-Jong Jin, William Donaldson

Chemistry Faculty Research and Publications

The reaction of acyclic tricarbonyl(pentadienyl)iron(1+) cations with allyl trimethylsilane or with excess furan leads to (E,E-diene)iron complexes. Attack of these weak nucleophiles on the transoid form of the pentadienyl cation is presumably faster than attack on the more stable cisoid form.


Secure And Private Distribution Of Online Video And Some Related Cryptographic Issues, Feng Bao, Robert H. Deng, Peirong Bao, Yan Guo, Hongjun Wu Jul 2001

Secure And Private Distribution Of Online Video And Some Related Cryptographic Issues, Feng Bao, Robert H. Deng, Peirong Bao, Yan Guo, Hongjun Wu

Research Collection School Of Computing and Information Systems

With the rapid growth of broadband infrastructure, it is thought that the bottleneck for video-on-demand service through Internet is being cleared. However, digital video content protection and consumers privacy protection emerge as new major obstacles. In this paper we propose an online video distribution system with strong content security and privacy protection. We mainly focus on the study of security and privacy problems related to the system. Besides presenting the new system, we intensively discuss some relevant cryptographic issues, such as content protection, private information retrieval, super-speed encryption/decryption for video, and PKC with fast decryption etc. The paper can be …


Application Of A Watershed Model (Basinsim) And A Tidal Prism Water Quality Model (Tpwqm) To The Great Wicomico River, Virginia, Sung-Chan Kim, Richard Wetzel, Leonard Hass, Albert Kuo Jul 2001

Application Of A Watershed Model (Basinsim) And A Tidal Prism Water Quality Model (Tpwqm) To The Great Wicomico River, Virginia, Sung-Chan Kim, Richard Wetzel, Leonard Hass, Albert Kuo

Reports

The objective of this project is to develop a modeling package to assist in water quality management of small coastal basins (SCBs) of the Chesapeake Bay system. Efforts by the Commonwealth to address water quality and its effect on living resources in tidal, estuarine systems has focused primarily on the Chesapeake Bay and the major tributaries of the lower bay (James, York and Rappahannock Rivers), as evidenced by the extensive monitoring and modeling efforts directed to them. This has been at the expense of smaller coastal basins such as the Great Wicomico River and the numerous tidal creek systems of …


On The Utility Of Entanglement In Quantum Neural Computing, Dan A. Ventura Jul 2001

On The Utility Of Entanglement In Quantum Neural Computing, Dan A. Ventura

Faculty Publications

Efforts in combining quantum and neural computation are briefly discussed and the concept of entanglement as it applies to this subject is addressed. Entanglement is perhaps the least understood aspect of quantum systems used for computation, yet it is apparently most responsible for their computational power. This paper argues for the importance of understanding and utilizing entanglement in quantum neural computation.


An Evaluation Of Shared Multicast Trees With Multiple Active Cores, Daniel Zappala, Aaron Fabbri Jul 2001

An Evaluation Of Shared Multicast Trees With Multiple Active Cores, Daniel Zappala, Aaron Fabbri

Faculty Publications

Core-based multicast trees use less router state, but have significant drawbacks when compared to shortest-path trees, namely higher delay and poor fault tolerance. We evaluate the feasibility of using multiple independent cores within a shared multicast tree. We consider several basic designs and discuss how using multiple cores improves fault tolerance without sacrificing router state. We examine the performance of multiple-core trees with respect to single-core trees and find that adding cores significantly lowers delay without increasing cost. Moreover, it takes only a small number of cores, placed with a k-center approximation, for a multiple-core tree to have lower delay …


Stochastic Properties Of Spacings In A Single-Outlier Exponential Model, Baha-Eldin Khaledi, Subhash C. Kochar Jul 2001

Stochastic Properties Of Spacings In A Single-Outlier Exponential Model, Baha-Eldin Khaledi, Subhash C. Kochar

Mathematics and Statistics Faculty Publications and Presentations

Let X1,..., Xn be independent exponential random variables with possibly different scale parameters. Kochar and Korwar [J. Multivar. Anal. 57 (1996)] conjectured that, in this case, the successive normalized spacings are increasing according to hazard rate ordering. In this article, we prove this conjecture in the case of a single-outlier exponential model when all except one of the parameters are identical. We also prove that the spacings are more dispersed and larger in the sense of hazard rate ordering when the vector of scale parameters is more dispersed in the sense of majorization.


Mantle Deformation Beneath Southern Africa, Paul G. Silver, Stephen S. Gao, Kelly H. Liu, Kaapvaal Seismic Group Jul 2001

Mantle Deformation Beneath Southern Africa, Paul G. Silver, Stephen S. Gao, Kelly H. Liu, Kaapvaal Seismic Group

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Seismic anisotropy from the southern African mantle has been inferred from shear-wave splitting measured at 79 sites of the Southern African Seismic Experiment. These data provide the most dramatic support to date that Archean mantle deformation is preserved as fossil mantle anisotropy. Fast polarization directions systematically follow the trend of Archean structures and splitting delay times exhibit geologic control. The most anisotropic regions are Late-Archean in age (Zimbabwe craton, Limpopo belt, western Kaapvaal craton), with delay times reduced dramatically in off-craton regions to the southwest and Early-Archean regions to the southeast. While thin lithosphere can account for weak off-craton splitting, …


An Information Theoretic Methodology For Prestructuring Neural Networks, Bjorn Chambless, George G. Lendaris, Martin Zwick Jul 2001

An Information Theoretic Methodology For Prestructuring Neural Networks, Bjorn Chambless, George G. Lendaris, Martin Zwick

Systems Science Faculty Publications and Presentations

Absence of a priori knowledge about a problem domain typically forces use of overly complex neural network structures. An information-theoretic method based on calculating information transmission is applied to training data to obtain a priori knowledge that is useful for prestructuring (reducing complexity) of neural networks. The method is applied to a continuous system, and it is shown that such prestructuring reduces training time, and enhances generalization capability.


Mobile Commerce: Promises, Challenges And Research Agenda, Keng Siau, Ee Peng Lim Jul 2001

Mobile Commerce: Promises, Challenges And Research Agenda, Keng Siau, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Advances in wireless technology increase the number of mobile device users and give pace to the rapid development of e-commerce using these devices. The new type of e-commerce, conducting transactions via mobile terminals, is called mobile commerce. Due to its inherent characteristics such as ubiquity, personalization, flexibility, and dissemination, mobile commerce promises businesses unprecedented market potential, great productivity, and high profitability. This paper presents an overview of mobile commerce development by examining the enabling technologies, the impact of mobile commerce on the business world, and the implications to mobile commerce providers. The paper also provides an agenda for future research …


Feedback Correction Of Angular Error In Grating Readout, Monish Ranjan Chatterjee, Sundaram Ramachandran Jul 2001

Feedback Correction Of Angular Error In Grating Readout, Monish Ranjan Chatterjee, Sundaram Ramachandran

Electrical and Computer Engineering Faculty Publications

Angular and wavelength READ beam errors in holographic interconnection systems are often a recurrent problem. Several strategies have been proposed to minimize or eliminate such READOUT misalignments.

Some years ago, Chatterjee and co-workers proposed a method involving READ beam wavelength tuning to correct output angular errors. In this paper, we investigate the possibility of using an acousto-optic (A-O) Bragg cell with optoelectronic feedback to dynamically correct the scattered beam for deviations in the incidence direction of the READ beam of a hologram. The concept here is based on an acoustic frequency feedback strategy used recently by Balakshy and Kazaryan for …


Recent Advances In Content-Based Video Analysis, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang Jul 2001

Recent Advances In Content-Based Video Analysis, Chong-Wah Ngo, Ting-Chuen Pong, Hong-Jiang Zhang

Research Collection School Of Computing and Information Systems

In this paper, we present major issues in video parsing, abstraction, retrieval and semantic analysis. We discuss the success, the difficulties and the expectations in these areas. In addition, we identify important opened problems that can lead to more sophisticated ways of video content analysis. For video parsing, we discuss topics in video partitioning, motion characterization and object segmentation. The success in video parsing, in general, will have a great impact on video representation and retrieval. We present three levels of abstracting video content by scene, keyframe and key object representations. These representation schemes in overall serve as a good …


Riparian Forest Buffer Restoration Targeting For The York River Watershed, Anne Newsome, Carl Hershner, Dan Schatt, Virginia Institute Of Marine Science, Wetlands Program Jul 2001

Riparian Forest Buffer Restoration Targeting For The York River Watershed, Anne Newsome, Carl Hershner, Dan Schatt, Virginia Institute Of Marine Science, Wetlands Program

Reports

No abstract provided.


Securing Web Servers Against Insider Attack, Shan Jiang, Sean Smith, Kazuhiro Minami Dartmouth College Jul 2001

Securing Web Servers Against Insider Attack, Shan Jiang, Sean Smith, Kazuhiro Minami Dartmouth College

Computer Science Technical Reports

Too often, ``security of Web transactions'' reduces to ``encryption of the channel''---and neglects to address what happens at the server on the other end. This oversight forces clients to trust the good intentions and competence of the server operator---but gives clients no basis for that trust. Furthermore, despite academic and industrial research in secure coprocessing, many in the computer science community still regard ``secure hardware'' as a synonym for ``cryptographic accelerator.' This oversight neglects the real potential of COTS secure coprocessing technology to establish trusted islands of computation in hostile environments---such as at web servers with risk of insider attack. …


Measurement Of The Gπnn(T) Form Factor, Kelly Gene Vansyoc Jul 2001

Measurement Of The Gπnn(T) Form Factor, Kelly Gene Vansyoc

Physics Theses & Dissertations

Cross sections were measured for the reaction 1H(e, e′π+) n at the energy W = 1.95 GeV and momentum transfer Q2 = 0.6 (GeV/c)2. At this W and Q2, the longitudinal cross section is dominated by t-channel production, giving a unique opportunity to examine the strong coupling form factor gπNN(t). The measured cross sections were separated using a method similar to a Rosenbluth separation. For the extraction of gπNN(t), the Actor and Körner model [42] and a parameterization of the MAID2000 …


The Crest, Summer 2001, Virginia Institute Of Marine Science Jul 2001

The Crest, Summer 2001, Virginia Institute Of Marine Science

Reports

Table of Contents:

  • VIMS to Begin New Ecosystem Management Study
  • CBNERRVA Receives Coastal America Partnership Award
  • VIMS Shoreline Permit Application Reports Now Available Online
  • Marina Program Launched
  • Web Based Education Hub Developed by VIMS/Sea Grant Educators
  • In the middle of the storm... where VIMS scientists plan to be
  • Continental margins--where the action is
  • Aquaculture and agriculture--working together for solutions
  • Marine Finfish Culture Activities
  • Kauffman Aquaculture Center Campaign
  • New Graduate Courses for Science Teachers
  • VIMS scientists explore pollution of Antarctic sea ice
  • Mid-Atlantic Scallop Closed Areas Set to Reopen
  • VIMS study poses new questions on river carbon
  • Marine Industry Trends
  • Stranded …


Vims Shoreline Permit Database Impacts And Alterations Impacts And Alterations Summary 1993- 2000, Thomas A. Barnard, Patty Clancy, Karen Duhring, Kirk J. Havens, Carl Hershner, Pamela Mason, David O'Brien, Walter L. Priest, William L. Roberts, Lyle M. Varnell, David Weiss, Virginia Institute Of Marine Science, Wetlands Program Jul 2001

Vims Shoreline Permit Database Impacts And Alterations Impacts And Alterations Summary 1993- 2000, Thomas A. Barnard, Patty Clancy, Karen Duhring, Kirk J. Havens, Carl Hershner, Pamela Mason, David O'Brien, Walter L. Priest, William L. Roberts, Lyle M. Varnell, David Weiss, Virginia Institute Of Marine Science, Wetlands Program

Reports

No abstract provided.


An Investigation On The Impact Of Implementing Visual Quantum Mechanics On Student Learning And Student Instructor Beliefs, Lawrence Escalada Jul 2001

An Investigation On The Impact Of Implementing Visual Quantum Mechanics On Student Learning And Student Instructor Beliefs, Lawrence Escalada

Faculty Publications

Aspects of the Visual Quantum Mechanics instructional materials have been adapted and implemented into a university physical science course for pre-service elementary education majors and various high school physics classrooms. These materials utilize a learning cycle pedagogy involving interactive, simulation computer programs and inexpensive devices to introduce basic quantum physics ideas within the context of fundamental physics concepts. A brief description of how these materials and strategies were adapted and implemented in high school classrooms will be provided. The results found on student conceptual learning and student/instructor attitudes and beliefs will also be briefly discussed.


Development Of Atlas Based Simulation Capability For Automated Testing, Rami Hanbali Jul 2001

Development Of Atlas Based Simulation Capability For Automated Testing, Rami Hanbali

Electrical & Computer Engineering Theses & Dissertations

Computer software is emerging as a powerful tool for controlling a large number of instruments and for the testing of these instruments. The main aim of this work is to provide a software program capable of controlling a large number of engineering instruments at the touch of a button. In addition, the software is to have the capability of connecting the instruments with the desired Unit Under Test. There is great need for such software driven testing in industry, especially for large complex systems. Advantages of such an approach include: (a) automated testing in a very quick and efficient manner; …


Pulsed Electron Heating Of Atmospheric Pressure Air Glow Discharges, Hisham Merhi Jul 2001

Pulsed Electron Heating Of Atmospheric Pressure Air Glow Discharges, Hisham Merhi

Electrical & Computer Engineering Theses & Dissertations

By applying electric field pulses of short duration (compared to the time constant for glow-to-arc transitions) to a weakly ionized gas, the electron energy distribution can be temporarily shifted to higher energies. This effect causes a nonlinear increase in the ionization rate and consequently a larger electron decay time. This effect has been demonstrated using single pulse operation.3 In order to generate plasma with semi-continuous electron density, repetitive operation is required. As a first step towards repetitive pulsed electric field operation, the temporal development of the voltage across the plasma for two subsequent pulses was measured. The dual pulse …


Dynamical Sedimentary Models Of Shallow Marine Environments, Yong Zhang Jul 2001

Dynamical Sedimentary Models Of Shallow Marine Environments, Yong Zhang

OES Theses and Dissertations

This treatise represents a contribution of quantitative, dynamical sedimentary modeling to the analytical understanding of sedimentary processes in shallow marine environments. The dynamical sedimentary models in this treatise numerically simulate the sedimentary processes from an event time scale, based on the fundamental physics of sediment dynamics in coastal and shelf depositional environments, to a longer, facies time scale. The simulated geologic processes serve to the illustrate shoreface equilibrium profile, shelf storm bed generation, and the shelf sedimentary facies system.

This treatise presents a nearshore profile evolution model for the abandoned Huanghe Delta, a two-dimensional storm deposition model, and a sedimentary …


Minimum Mean Square Error Spectral Peak Envelope Estimation For Automatic Vowel Classification, Jaishree Venugopal Jul 2001

Minimum Mean Square Error Spectral Peak Envelope Estimation For Automatic Vowel Classification, Jaishree Venugopal

Electrical & Computer Engineering Theses & Dissertations

Spectral feature computations continue to be a very difficult problem for accurate machine recognition of speech. In this work, which focuses on vowels, a new spectral peak envelope method for vowel classification is developed, based on a missing frequency components model of speech recognition. According to the missing frequency components model, vowel recognition depends only on the spectral (harmonic) peaks. Smoothing and interpolation of the spectra, performed in the standard cepstral analysis method commonly used in automatic speech recognition, actually loses valuable information and results in reduced recognition accuracy. The new method for feature extraction presented in this thesis is …


Transverse Variability Of The Flow And Density In Inlets Of Southern Chile, Mario Arturo Cáceres Muñoz Jul 2001

Transverse Variability Of The Flow And Density In Inlets Of Southern Chile, Mario Arturo Cáceres Muñoz

OES Theses and Dissertations

Measurements of velocity and density profiles were made to describe the flow transverse structure in three inlets of southern Chile. The inlets show marked differences in their transverse dynamics in response to external forcing. In Aysen Fjord (45.2°S) the mean flow showed a three layer structure that was consistent with up-fjord wind-induced exchange, while in Chacao Channel (41.8°S), the mean flow exhibited predominantly a lateral structure that featured sharp velocity shears. In both cases, a bank in the center of the sections seemed to play an important role in shaping the mean flows. In Ventisquero Sound (44.4°S), the presence of …


Application-Centric Analysis Of Ip-Based Mobility Management Techniques, Archan Misra, Subir Das, Prathima Agrawal Jul 2001

Application-Centric Analysis Of Ip-Based Mobility Management Techniques, Archan Misra, Subir Das, Prathima Agrawal

Research Collection School Of Computing and Information Systems

This paper considers three applications—VoIP, mobile Web access and mobile server-based data transfers—and evaluates the applicability of various IP-based mobility management mechanisms. We first survey the features and characteristics of various IP mobility protocols, such as MIPv4, MIPv6, MIP-RO, SIP, CIP, HAWAII, MIP-RR and IDMP, and then evaluate their utility on an application-specific basis. The diversity in the mobility-related requirements ensures that no single mobility solution is universally applicable. We recommend a hierarchical mobility architecture. The framework uses our Dynamic Mobility Agent (DMA) architecture for managing intra-domain mobility and multiple application-based binding protocols for supporting inter-domain mobility. Thus, we recommend …


Hydrographic Variability On Decadal And Interdecadal Scales In The Northern Gulf Of Alaska, Nandita Sarkar Jul 2001

Hydrographic Variability On Decadal And Interdecadal Scales In The Northern Gulf Of Alaska, Nandita Sarkar

OES Theses and Dissertations

The mixed layer depth (MLD) in the North Pacific is important to vertical mixing and hence the flux nutrients into the euphotic zone. A time series of hydrographic measurements, tem perature and salinity versus depth, at a coastal site in the northern Gulf of Alaska is used to determine the seasonal and interannual variations in the MLD. Data from this station called GAK 1 (59°50.7‘X. 149C28.0'\V) in 203 m of water begin in 1974 and end in 1998. The MLD changes seasonally from about 50 m in summer to more than 130 m in winter. These changes are in response …


Trichodesmium Spp.: Numerical Studies Of Resource Competition, Carbohydrate Ballasting, And Remote-Sensing Reflectance, Tonya Denise Clayton Jul 2001

Trichodesmium Spp.: Numerical Studies Of Resource Competition, Carbohydrate Ballasting, And Remote-Sensing Reflectance, Tonya Denise Clayton

OES Theses and Dissertations

In recent years, a new appreciation for the role of diazotrophy in the oceans has emerged. This dissertation reports on three modeling studies designed to investigate ecological processes associated with Trichodesmium spp., the most conspicuous marine diazotroph: (1) characterization of a generalized model Trichodesmium and issues of macronutrient resource competition; (2) carbohydrate ballasting by Trchodesmium and implications for the formation of surface accumulations; and (3) the vertical distribution of Trichodesmium and implications for detection from space.

The first study focuses on issues of nitrogen and phosphorus competition and ecosystem structure. It utilizes a simple ecosystem model that includes dissolved nitrogen …