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2001

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Full-Text Articles in Physical Sciences and Mathematics

Advanced Searchers???, Jimmy Ghaphery Jan 2001

Advanced Searchers???, Jimmy Ghaphery

VCU Libraries Faculty and Staff Presentations

Log analysis from 2001 focused on use and popularity of advanced search features of an online library catalog (OPAC).


Evolution Of Deep Centers In Gan Grown By Hydride Vapor Phase Epitaxy, Z-Q. Fang, David C. Look, J. Jasinski, M. Benamara, Z. Liliental-Weber, Richard J. Molnar Jan 2001

Evolution Of Deep Centers In Gan Grown By Hydride Vapor Phase Epitaxy, Z-Q. Fang, David C. Look, J. Jasinski, M. Benamara, Z. Liliental-Weber, Richard J. Molnar

Physics Faculty Publications

Deep centers and dislocation densities in undoped n GaN, grown by hydride vapor phase epitaxy (HVPE), were characterized as a function of the layer thickness by deep level transient spectroscopy and transmission electron microscopy, respectively. As the layer thickness decreases, the variety and concentration of deep centers increase, in conjunction with the increase of dislocation density. Based on comparison with electron-irradiation induced centers, some dominant centers in HVPE GaN are identified as possible point defects.


Synthesis And Characterization Of A Ruthenium-Thioxane Complex, Amanda Wroble, Scotty Sproles, Mark Draganjac, Paul M. Nave Jan 2001

Synthesis And Characterization Of A Ruthenium-Thioxane Complex, Amanda Wroble, Scotty Sproles, Mark Draganjac, Paul M. Nave

Journal of the Arkansas Academy of Science

No abstract provided.


Test 1792: Massey Ferguson 2210 Diesel 15-Speed, Nebraska Tractor Test Lab Jan 2001

Test 1792: Massey Ferguson 2210 Diesel 15-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA

The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data.

EXPLANATION OF THE TEST PROCEDURES

Purpose

The purpose of …


Scintillation Behind The Collecting Lens Of A Receiver, Clarissa A. Fleming Russell Jan 2001

Scintillation Behind The Collecting Lens Of A Receiver, Clarissa A. Fleming Russell

Retrospective Theses and Dissertations

One of the negative effects that a laser beam experiences as it propagates through the atmosphere is intensity fluctuations or scintillation. Because scintillation-- as it pertains to laser radar and laser satellite communication systems-- is the main subject of this research, the assumption of an optical element ( such as a Gaussian lens) along the propagation path in front of the detector is valid. The mathematical addition of optical elements to the propagation path is treated using the ABCD ray matrix method. The expression for scintillation is derived, analyzed, and numerically calculated for positions to the left and right of …


Using Computers In The Administration Of Primary Schools, Donncha Ó Fiannachta Jan 2001

Using Computers In The Administration Of Primary Schools, Donncha Ó Fiannachta

Theses

This project investigates the use of computers in the administration of primary schools. A survey has been undertaken to determine current usage and future needs of schools such as training requirements.

It contains an overview of international thinking in this area and looks at aspects such as the legal issues involved in the keeping of electronic data on individuals in schools. Reference is made to the Freedom of Information Act, Data Protection Act and the Education Act.

The author has determined the type of data that is most commonly needed by primary schools in Ireland. Some of this information must …


Tackling The Deficit - It Solutions For Art Appreciation - Needs Study And Provision Project At Primary School Level., Séan Ó Hargáin Jan 2001

Tackling The Deficit - It Solutions For Art Appreciation - Needs Study And Provision Project At Primary School Level., Séan Ó Hargáin

Theses

This project looks at the changing environment in terms of the approach to the Visual Arts curriculum at Primary School level. It aims to provide an innovative solution to the art appreciation area, which is being given equal status with the art creation area, which traditionally has been the main focus of the curriculum.

The Project includes a review of the curricular climate, both at home and abroad. In this context it focusses particularly on the role of Information Technology in addressing access problems from those living remote from major population, and therefore major artistic centres.

Primary Research included involved …


Development Of Non-Contact Scanning Force Microscopy For Imaging In Liquid Environments, Anthony Grant Jan 2001

Development Of Non-Contact Scanning Force Microscopy For Imaging In Liquid Environments, Anthony Grant

Theses

The aim of this work was to develop a non-contact mode scanning force microscope (SFM) for application to biological samples within liquid environments. Given that biological samples are particularly soft in their natural state and that a liquid is the most difficult operating environment for non-contact mode scanning force microscopy, the development of an instrument that is optimised to image biological samples in vitro presents significant challenges.

Firstly, the SFM tip to sample interaction has to be minimised either, in the worst case, to prevent the sample from being detached from its support or to maximise spatial resolution by minimising …


An Approach To Networking In Irish Primary Schools, Donal A. O'Connor Jan 2001

An Approach To Networking In Irish Primary Schools, Donal A. O'Connor

Theses

In this Thesis, I hope to develop an approach to networking in the Irish Primary school which will provide practical as well as theoretical advice to Primary Teachers. In the pages that follow, I will detail a general outline of the principles of computer networking and detail models appropriate to the primary school.

At the outset, I wish to acknowledge that there are as many solutions to the primary school’s networking requirements as there are individual schools. This document is intended as a general set of guidelines for the average Primary school in this country. By this, I mean schools …


On Stochastic Comparisons Of Energy Functions With Applications, Broderick O. Oluyede Jan 2001

On Stochastic Comparisons Of Energy Functions With Applications, Broderick O. Oluyede

Department of Mathematical Sciences Faculty Publications

We develop simple methods for the stochastic comparisons of informational energy functions. We introduce modified informational energy functions and uncertainty of parameter functions are introduced for models with realistic parameter spaces. We present inequalities, comparisons, and applications including test procedures for testing the equality of informational energy functions. Some illustrative examples are also presented.


Expanding The Notion Of Relevance In Is Research: A Proposal And Some Recommendations, Deepak Khazanchi, Bjørn Erik Munkvold Jan 2001

Expanding The Notion Of Relevance In Is Research: A Proposal And Some Recommendations, Deepak Khazanchi, Bjørn Erik Munkvold

Information Systems and Quantitative Analysis Faculty Publications

Based on an analysis of a priori discussion on the notion of relevance, this paper proposes a holistic view of relevance in IS research. This expanded notion of relevance incorporates a broader definition of audience/stakeholder, and includes additional dimensions such as scope/value of relevant research, time frame, and "situatedness" of relevance. In view of this definition, it is argued that "practical relevance" is not the sole goal of academic research. Hence, the authors recommend, for example, that knowledge claims in IS need to be better communicated and targeted for the future development and recognition of the IS discipline.


Growth, Structure, Electronic, And Magnetic Properties Of Mgo/Fe(001) Bilayers And Fe/Mgo/Fe(001) Trilayers, M. Klaua, D. Ullmann, J. Barthel, W. Wulfhekel, J. Kirschner, R. Urban, Theodore L. Monchesky, Axel Enders, John F. Cochran, Brett Heinrich Jan 2001

Growth, Structure, Electronic, And Magnetic Properties Of Mgo/Fe(001) Bilayers And Fe/Mgo/Fe(001) Trilayers, M. Klaua, D. Ullmann, J. Barthel, W. Wulfhekel, J. Kirschner, R. Urban, Theodore L. Monchesky, Axel Enders, John F. Cochran, Brett Heinrich

Axel Enders Publications

Single-crystal epitaxial MgO thin films were grown directly onto high-quality Fe single crystal and Fe whisker substrates and covered with Fe/Au layers. Reflection high-energy electron diffraction and low-energy electron diffraction patterns and scanning tunneling microscopy images showed that the growth of MgO proceeded pseudomorphically in a nearly layer-by-layer mode up to six monolayers. A misfit dislocation network is formed for MgO layers thicker than six monolayers. The thin MgO films were characterized electrically by scanning tunneling spectroscopy. The tunneling barrier in MgO was found to depend on the MgO layer thickness, starting from 2.5 eV at two monolayer thickness to …


B-Nodes: A New Scalable High Level Abstraction Model, Stanislaw P. Maj, Craig William Caulfield Jan 2001

B-Nodes: A New Scalable High Level Abstraction Model, Stanislaw P. Maj, Craig William Caulfield

Research outputs pre 2011

This paper proposes a new modeling technique called B-Nodes. B-Nodes represent a new, high-level abstraction that allows technical detail to be controlled using top-down recursive decomposition. This abstraction. is independent of architectural detail and can therefore accommodate rapid changes in technology. The use of recursive decomposition allows B-Nodes to be used not only for entire e-commerce system but also sub-modules within this system. The use of fundamental units allows the performance of heterogeneous technologies to be compared and other units to be derived. Results to date indicate no comparable model exists. Should further work validate this technique the authors recommend …


Clustering Of Web Users Using Session-Based Similarity Measures, Jitian Xiao, Yanchun Zhang Jan 2001

Clustering Of Web Users Using Session-Based Similarity Measures, Jitian Xiao, Yanchun Zhang

Research outputs pre 2011

One important research topic in web usage mining is the clustering of web users based on their common properties. Informative knowledge obtained from web user clusters were used for many applications, such as the prefetching of pages between web clients and proxies. This paper presents an approach for measuring similarity of interests among web users from their past access behaviors. The similarity measures are based on the user sessions extracted from the user's access logs. A multi-level scheme for clustering a large number of web users is proposed, as an extension to the method proposed in our previous work (2001). …


A Case For Systems Thinking And System Dynamics, Craig William Caulfield, Stanislaw P. Maj Jan 2001

A Case For Systems Thinking And System Dynamics, Craig William Caulfield, Stanislaw P. Maj

Research outputs pre 2011

Systems thinking is a way of thinking that focuses on the relationships between the parts forming a purposeful whole. System dynamics is concerned with building computer models of complex problem situations and then experimenting with and studying the behaviour of these models over time. This paper is a review of systems thinking that considers its unique history and influences, paradigms and methodologies, and presents a case for the system dynamics methodology as the best tool for the most diverse range of problem situations


Inference Of Regular Languages Using Model Simplicity, Philip Hingston Jan 2001

Inference Of Regular Languages Using Model Simplicity, Philip Hingston

Research outputs pre 2011

We describe an approach that is related to a number of existing algorithms for the inference of a regular language from a set of positive (and optionally also negative) examples. Variations on this approach provide a family of algorithms that attempt to minimise the complexity of a description of the example data in terms of a finite state automaton model. Experiments using a standard set of small problems show that this approach produces satisfactory results when positive examples only are given, and can be helpful when only a limited number of negative examples is available. The results also suggest that …


Heckman's Methodology For Correcting Selectivity Bias : An Application To Road Crash Costs, Margaret Giles Jan 2001

Heckman's Methodology For Correcting Selectivity Bias : An Application To Road Crash Costs, Margaret Giles

Research outputs pre 2011

Aggregate road crash costs are traditionally determined using average costs applied to incidence figures found in Police-notified crash data. Such data only comprise a non-random sample of the true population of road crashes, the bias being due to the existence of crashes that are not notified to the Police. The traditional approach is to label the Police-notified sample as 'non-random' thereby casting a cloud over data analyses using this sample. Heckman however viewed similar problems as 'omitted variables' problems in that the exclusion of some observations in a systematic manner (so-called selectivity bias) has inadvertently introduced the need for an …


Are Bank Deposits And Bank-Affiliated Managed Funds Close Substitutes?, David E. Allen, Jerry T. Parwada Jan 2001

Are Bank Deposits And Bank-Affiliated Managed Funds Close Substitutes?, David E. Allen, Jerry T. Parwada

Research outputs pre 2011

This study tests the hypothesis that bank liabilities and managed funds are close substitutes. Some literature associates the alleged decline in banking business with the disintermediation of banks’ traditional deposit-taking business in favour of investment management. A comparative assessment of managed fund and bank deposit qualitative attributes fails to support substitutability. Using data on Australian bank-affiliated funds and a nine-year record of bank liability balances, this study finds that, empirically, managed funds do not displace bank liabilities. Prudential capital adequacy requirements dissuade banks from using in-house managed investments as indirect conduits for raising funds in the same manner as deposit …


Some Statistical Models For Durations And Their Applications In Finance, Harry Zheng, David E. Allen, Lyn C. Thomas Jan 2001

Some Statistical Models For Durations And Their Applications In Finance, Harry Zheng, David E. Allen, Lyn C. Thomas

Research outputs pre 2011

We first consider a new class of time series models (introduced by Engle and Russell (1998)) use in statistical applications in finance. These models treat the time between events (durations) as a stochastic process and the corresponding durations are modelled using a theory similar to that of autoregressive processes. This new class of time series models is called Autoregressive Conditional Duration (ACD) models. Various extensions and the statistical properties of this class of ACD models are given. We also suggest some alternative models for durations arising from the market microstructure literature. An estimation procedure is discussed. The theory is illustrated …


The Duration Derby : A Comparison Of Duration Based Strategies In Asset Liability Management, Harry Zheng, David E. Allen, Lyn C. Thomas Jan 2001

The Duration Derby : A Comparison Of Duration Based Strategies In Asset Liability Management, Harry Zheng, David E. Allen, Lyn C. Thomas

Research outputs pre 2011

Macaulay duration matched strategy is a key tool in bond portfolio immunization. It is well known that if term structures are not at or changes are not parallel, then Macaulay duration matched portfolio can not guarantee adequate immunization. In this paper the approximate duration is proposed to measure the bond price sensitivity to changes of interest rates of non- at term structures. Its performance in immunization is compared with those of Macaulay, partial and key rate durations using the US Treasury STRIPS and Bond data. Approximate duration turns out to be a possible contender in asset liability management: it does …


Working For Excellence In The E-Conomy: 2nd International We-B Conference, Sue Stoney (Ed.) Jan 2001

Working For Excellence In The E-Conomy: 2nd International We-B Conference, Sue Stoney (Ed.)

Research outputs pre 2011

Welcome to Perth, Western Australia, and to the 2nd International We-B Conference 2001 "working for excellence in the e-conomy" hosted by the We-B Centre, School of Management Information Systems at Edith Cowan University.

This is an international conference for academics and industry specialists in e-business, e-government and related fields. The conference has drawn participants from national and international organisations.

All submitted papers were subjected to an anonymous peer review process managed by the Conference Committee.


Search For Electroweak Production Of Single Top Quarks In Pp̅ Collisions, B. Abbott Jan 2001

Search For Electroweak Production Of Single Top Quarks In Pp̅ Collisions, B. Abbott

Gregory Snow Publications

We present a search for electroweak production of single top quarks in the electron+jets and muon+jets decay channels. The measurements use ≈90 pb-1 of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the D Ø detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet, to set an upper limit at the 95% confidence level on the cross section for the s-channel process pp̅tb+X of 39 pb. The upper limit for the t-channel processpp̅tqb+X …


Crystal And Magnetic Structure Of Pr0.7sr0.3-Xmno3 (0 ≤ X ≤ 0.2) Compounds, Q. Cai, William B. Yelon, M. Ellouze, W. Boujelben, A. Cheikh-Rouhou Jan 2001

Crystal And Magnetic Structure Of Pr0.7sr0.3-Xmno3 (0 ≤ X ≤ 0.2) Compounds, Q. Cai, William B. Yelon, M. Ellouze, W. Boujelben, A. Cheikh-Rouhou

Physics Faculty Research & Creative Works

The electronic and magnetic properties of the ABO3 type manganite's (A = rare earth, B = Mn) depend sensitively on the ratio of divalent and trivalent atoms on the A sublattice. The substitution of rare-earth by Ca or Sr not only affects the total valence, but also the lattice spacing, which, in turn may affect the structure and magnetic ordering temperature. If these compounds are synthesized with less than stoichiometric amounts of the A site constituents, (relative to the Mn content), three possible outcomes may be considered: a) single phase materials with vacancies on the A sublattice may be formed, …


Generalized Block Diagram Of The Inner Bluegrass Karst, James C. Currens Jan 2001

Generalized Block Diagram Of The Inner Bluegrass Karst, James C. Currens

Map and Chart--KGS

Karst occurs where limestone or other soluble bedrock is near the earth's surface, and fractures in the rock become enlarged when the rock dissolves. Sinkholes and sinking streams are two surface features that indicate karst development. In karst areas most rainfall sinks underground, resulting in fewer streams flowing on the surface than in non-karst settings. Instead of flowing on the surface, the water flows underground through caves, sometimes reemerging at karst windows, then sinks again to eventually discharge at a base-level spring along a major stream or at the top of an impermeable strata. The development of karst features is …


Generalized Block Diagram Of The Eastern Pennyroyal Karst, James C. Currens Jan 2001

Generalized Block Diagram Of The Eastern Pennyroyal Karst, James C. Currens

Map and Chart--KGS

Karst occurs where limestone or other soluble bedrock is near the earth's surface, and fractures in the rock become enlarged when the rock dissolves. Sinkholes and sinking streams are two surface features that indicate karst development. In karst areas most rainfall sinks underground, resulting in fewer streams flowing on the surface than in non-caves, sometimes reemerging at karst windows, then sinks again to eventually discharge at a base-level spring along a major stream or at the top of an impermeable strata. The development of karst features is influenced by the type of soluble rock and how it has been broken …


Geologic Map Of Kentucky, M. C. Noger Jan 2001

Geologic Map Of Kentucky, M. C. Noger

Map and Chart--KGS

No abstract provided.


Protect Kentucky's Karst Aquifers From Nonpoint-Source Pollution, James C. Currens Jan 2001

Protect Kentucky's Karst Aquifers From Nonpoint-Source Pollution, James C. Currens

Map and Chart--KGS

No abstract provided.


Karst Occurrence In Kentucky, Randall L. Paylor, James C. Currens Jan 2001

Karst Occurrence In Kentucky, Randall L. Paylor, James C. Currens

Map and Chart--KGS

This map was compiled from a digital version of the 1:500,000-scale geologic map of Kentucky (Noger, M.C., comp., 1988, Geologic map of Kentucky: U.S. Geological Survey). The areas of potential karst development were delineated using stratigraphic units mapped on the geological map. The classification of the potential for karst development was based on the field experience of the authors and other data. A number of isolate carbonated unites that would not have otherwise been differentiated on the geologic map were newly digitized for this map.


Detection Of P2x Purinergic Receptors On Human B Lymphocytes, Ronald Sluyter, J A. Barden, James Wiley Jan 2001

Detection Of P2x Purinergic Receptors On Human B Lymphocytes, Ronald Sluyter, J A. Barden, James Wiley

Faculty of Science - Papers (Archive)

B lymphocytes are known to synthesise the P2X(7) subtype of the P2X purinergic receptor family; however, the identification of the other six P2X subtypes on these cells has been limited by the absence of specific antibodies. In this study, we used a panel of anti-P2X polyclonal antibodies and confocal microscopy to examine the presence of each P2X receptor on human B lymphocytes. We observed that P2X(1), P2X(2), P2X(4) and P2X(7) subtypes, but not P2X(3), P2X(5) and P2X(6) subtypes, are present on B lymphocytes.


Molecular Dynamics Simulation Of Biomolecular Systems, Wilfred Van Gunsteren, Dirk Bakowies, Roland Buergi, Indira Chandrasekhar, Markus Christen, Xavier Daura, Peter Gee, Alice Glaettli, Tomas Hansson, Chris Oostenbrink, Christine Peter, Jed Pitera, Lukas Schuler, Thereza Soares, Haibo Yu Jan 2001

Molecular Dynamics Simulation Of Biomolecular Systems, Wilfred Van Gunsteren, Dirk Bakowies, Roland Buergi, Indira Chandrasekhar, Markus Christen, Xavier Daura, Peter Gee, Alice Glaettli, Tomas Hansson, Chris Oostenbrink, Christine Peter, Jed Pitera, Lukas Schuler, Thereza Soares, Haibo Yu

Faculty of Science - Papers (Archive)

The group for computer-aided chemistry at the ETH Zurich focuses its research on the development of methodology to simulate the behavior of biomolecular systems and the use of simulation techniques to analyze and understand biomolecular processes at the atomic level. Here, the current research directions are briefly reviewed and illustrated with a few examples.