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Full-Text Articles in Physical Sciences and Mathematics

The Ohio Gis Network: Stage 1 1993 Investment Fund Development Grant Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling Jan 1997

The Ohio Gis Network: Stage 1 1993 Investment Fund Development Grant Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling

All Maxine Goodman Levin School of Urban Affairs Publications

The Ohio Geographic Information Systems Network (Ohio GIS-Net) is an innovative consortium of Ohio’s urban and rural universities. The consortium is building a center of excellence where state-of-the-art geographic information systems (GIS) technology is applied to a research agenda that is critical to Ohio's economic development and central to research issues in policy sciences, civil engineering, public administration, economics and the environmental, urban and regional sciences. This cutting edge technology is an essential component of the basic research infrastructure of universities. It is also a critical resource in state and local economic development efforts, building and maintaining public infrastructure, and …


The Ohio Gis Network: Stage 2 1996 Investment Fund Grant First Year Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling Jan 1997

The Ohio Gis Network: Stage 2 1996 Investment Fund Grant First Year Progress Report To The Ohio Board Of Regents (Ohio Gis Network), Mark Salling

All Maxine Goodman Levin School of Urban Affairs Publications

The Ohio Geographic Information Systems Network (Ohio GIS-Net) is an innovative consortium of Ohio’s urban and rural universities. The consortium is building a center of excellence where state-of-the-art geographic information systems (GIS) technology is applied to a research agenda that is critical to Ohio's economic development and central to research issues in policy sciences, civil engineering, public administration, economics and the environmental, urban and regional sciences. This cutting edge technology is an essential component of the basic research infrastructure of universities. It is also a critical resource in state and local economic development efforts, building and maintaining public infrastructure, and …


Measurement Of The Spectral Functions Of Vector Current Hadronic Tau Decays, R. Barate, M. Thulasidas Jan 1997

Measurement Of The Spectral Functions Of Vector Current Hadronic Tau Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the spectral functions of non-strange τ vector current final states is presented, using 124 358 τ pairs recorded by the ALEPH detector at LEP during the years 1991 to 1994. The spectral functions of the dominant two- and four-pion τ decay channels are compared to published results of e + e - annihilation experiments via isospin rotation. A combined fit of the pion form factor from τ decays and e + e - data is performed using different parametrizations. The mass and the width of the ρ ±(770) and the ρ 0(770) are separately determined in order …


Measurement Of The Τ Lepton Lifetime With The Three-Dimensional Impact Parameter Method, R. Barate, M. Thulasidas Jan 1997

Measurement Of The Τ Lepton Lifetime With The Three-Dimensional Impact Parameter Method, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A new method is presented for the measurement of the mean lepton lifetime using events in which are pair-produced and both's decay to hadrons.


The Topology Dependence Of Charged Particle Multiplicities In Three-Jet Events, R. Barate, M. Thulasidas Jan 1997

The Topology Dependence Of Charged Particle Multiplicities In Three-Jet Events, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A study of individual jet and whole-event charged particle multiplicities in three-jet events measured in e + e − annihilation at the Z reveals a significant topology dependence. Mean jet multiplicities are inadequately described by jet energies; interjet angles must also be specified. Quantitative tests suggest that it is necessary to use transversemomentum- like scales to describe the data.


A Study Of Τ Decays Involving Η And Ω Mesons, D. Buskulic, M. Thulasidas Jan 1997

A Study Of Τ Decays Involving Η And Ω Mesons, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The 132 pbt - 1 of data collected by ALEPH from 1991 to 1994 have been used to analyze η and ω production in τ decays. The following branching fractions have been measured: B(τ−→ντωh−)=(1.91±0.07±0.06)×10−2,B(τ−→ντωh−)=(1.91±0.07±0.06)×10−2, B(τ−→ντωh−π0)=(4.3±0.6±0.5)×10−3,B(τ−→ντωh−π0)=(4.3±0.6±0.5)×10−3, B(τ−→ντηK−)=(2.9+1.3−1.2±0.7)×10−4,B(τ−→ντηK−)=(2.9−1.2+1.3±0.7)×10−4, B(τ−→ντηh−π0)=(1.8±0.4±0.2)×10−3B(τ−→ντηh−π0)=(1.8±0.4±0.2)×10−3 and the 95% C.L. limit B(τ− → ντηπt -) t - 4 has been obtained. The ωπt- and ηπt -π0 rates and dynamics are found in agreement with the predictions made from e+e∼ - annihilation data with the help of isospin invariance (CVC).


Integrated Queries To Existing Bibliographic And Structured Databases, Ee Peng Lim, Ying Lu Jan 1997

Integrated Queries To Existing Bibliographic And Structured Databases, Ee Peng Lim, Ying Lu

Research Collection School Of Computing and Information Systems

It is widely accepted that future digital library applications have to be built upon different kinds of database servers to draw upon different forms of data, including bibliographic, text, multimedia, and structured data. In this paper, the problem of integrating existing public bibliographic databases and structured databases which reside at different locations in the network is addressed. Although bibliographic data is semistructured, its attribute set is often determined by an international standard known as MARC. To unify bibliographic and structured data, the well-known SQL was extended to model bibliographic related attributes and queries. In particular, a new data type was …


Improved Measurement Of The Bd0 -B̄D0 Oscillation Frequency, D. Buskulic, M. Thulasidas Jan 1997

Improved Measurement Of The Bd0 -B̄D0 Oscillation Frequency, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The time dependence of B0 d {B 0 d oscillations is measured by the ALEPH experiment at LEP, using three techniques, two of which are updates of previous measurements. In all cases the charge of the decaying b quark and its decay time are measured in one hemisphere of the event; the quark charge at production is tagged mainly using the opposite hemisphere. The first method uses the charge correlation between a D and a lepton in the opposite hemisphere; if no lepton is present, the produced quark charge is determined from the hemisphere charges. In the second method, the …


Production Of Orbitally Excited Charm Mesons In Semileptonic B Decays, D. Buskulic, M. Thulasidas Jan 1997

Production Of Orbitally Excited Charm Mesons In Semileptonic B Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

A sample of 3.6 million hadronic Z decays recorded between 1991 and 1995 with the ALEPH detector at LEP is used to investigate semileptonic decays of B mesons into final states involving orbitally excited charm mesons. Topological vertex criteria are used to search for decays involving narrow D** states as well as wide D** resonances and non-resonant D(*)π final states. The sum of the branching ratios for these processes is measured to be ${⤪ Br}({⩈erline {⤪ B}}⌝ghtarrow {⤪ D}≪ ⫑l^{-}{⩈erline v}) + {⤪ Br}({⩈erline {⤪ B}}⌝ghtarrow {⤪ D}^{⇒t}≪ ⫑l^{-}{⩈erline v})↦op =(2.26 pm 0.29({⤪ stat}) pm 0.33({⤪ syst}))%,$which accounts for a …


A Hypermedia Database To Manage World-Wide-Web Documents, Schubert Shou Boon Foo, Ee Peng Lim Jan 1997

A Hypermedia Database To Manage World-Wide-Web Documents, Schubert Shou Boon Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The surge of interest in the World-Wide-Web (WWW) with its potential commercial payoff has resulted in an explosion of information as organisations join in to publish and do business on the Internet. A related development, Intranet, which basically uses the same technology to build private corporate WWW-based networks, has emerged to provide cost-effective and efficient groupware and information management solutions for organisations. As a result, the Hyper Text Markup Language (HTML), used for constructing WWW documents, has become a contender for authoring future office documents. With this scenario, this study examines WWW practices and highlights the inadequacy and drawbacks of …


Managing World Wide Web Publications, Schubert Foo, Ee Peng Lim Jan 1997

Managing World Wide Web Publications, Schubert Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The surge of interest in the World Wide Web (WWW), with its potential commercial payoff, has resulted in an explosion of information as organizations join in the fray to publish and do business on the Internet. In addition, Intranet, the private corporate WWW‐based network, has also emerged to provide cost‐effective and efficient groupware and information management solutions for organizations. As a result, the HyperText Markup Language used for constructing WWW documents has become a contender for authoring future office documents. Examines the current practices of WWW publishing and highlights its inadequacies and drawbacks. Demonstrates the need and advantages of using …


Transverse Momentum Correlations In Hadronic Z Decays, D. Buskulic, M. Thulasidas Jan 1997

Transverse Momentum Correlations In Hadronic Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

Using data obtained with the ALEPH detector at the Z resonance, a measure based on transverse momentum is shown to exhibit a correlation between the two halves of a hadronic event which cannot be explained by energy-momentum conservation, flavour conservation, the imposition of an event axis or imperfect event reconstruction. Two possible interpretations based on existing Monte Carlo models are examined: a) ARIADNE, with the correlation forming early in the parton shower and with the transition from partons to hadrons playing only a minor part; b) JETSET, with the correlation forming at the fragmentation stage. A correlation technique based on …


Algorithms For Adapting Materialised Views In Data Warehouses, Mukesh Mohania, Guozhu Dong Dec 1996

Algorithms For Adapting Materialised Views In Data Warehouses, Mukesh Mohania, Guozhu Dong

Kno.e.sis Publications

In this paper we consider the problem of materialised view adaptation in data warehouses. Materialised views are important in data warehousing where they are used to speed up query processing on large amounts of data. User requirements change over time, which may change the definitions of views dynamically. For such situations, the question arises whether the materialised views should be recomputed from scratch for every change in the definition or they should be obtained by adapting old materialised views. Changes to a view definition may be expensive, if the view is recomputed from scratch. Therefore, it is worthwhile to examine …


Export Database Derivation Approach For Supporting Object-Oriented Wrapper Queries, Ee Peng Lim, Hon-Kuan Lee Dec 1996

Export Database Derivation Approach For Supporting Object-Oriented Wrapper Queries, Ee Peng Lim, Hon-Kuan Lee

Research Collection School Of Computing and Information Systems

Wrappers export the schema and data of existing heterogeneous databases and support queries on them. In the context of cooperative information systems, we present a flexible approach to specify the derivation of object-oriented (OO) export databases from local relational databases. Our export database derivation consists of a set of extent derivation structures (EDS) which defines the extent and deep extent of export classes. Having well-defined semantics, the EDS can be readily used in transforming wrapper queries to local queries. Based on the EDS, we developed a wrapper query evaluation strategy which handles OO queries on the export databases. The strategy …


Four-Fermion Production In E+E- Collisions At Centre-Of-Mass Energies Of 130 And 136 Gev, D. Buskulic, Manoj Thulasidas Nov 1996

Four-Fermion Production In E+E- Collisions At Centre-Of-Mass Energies Of 130 And 136 Gev, D. Buskulic, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

Four-fermion events have been selected in a data sample of 5.8 pb−1 collected with the aleph detector at centre-of-mass energies of 130 and 136 GeV. The final states ℓ+ℓ−qq, ℓ+ℓ−ℓ+ℓ−, ννqq, and ννℓ+ℓ− have been examined. Five events are observed in the data, in agreement with the Standard Model predictions of 6.67±0.38 events from four-fermion processes and 0.14−0.05+0.19 from background processes.


On The Portability Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing Oct 1996

On The Portability Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing

Kno.e.sis Publications

Goossens defined a structural operational semantics for a subset of VHDL-87 and proved that the parallelism present in VHDL is benign. We extend this work to include shared variables in VHDL-93 that changes the underlying semantic model. In the presence of shared variables, non-deterministic execution of VHDL-93 processes destroys the unique meaning property. We identify and characterize a class of portable VHDL-93 descriptions for which unique meaning property can be salvaged.


An Evidential Reasoning Approach To Attribute Value Conflict Resolution In Database Integration, Ee Peng Lim, Jaideep Srivastava, Shashi Shekhar Oct 1996

An Evidential Reasoning Approach To Attribute Value Conflict Resolution In Database Integration, Ee Peng Lim, Jaideep Srivastava, Shashi Shekhar

Research Collection School Of Computing and Information Systems

Resolving domain incompatibility among independently developed databases often involves uncertain information. DeMichiel [1] showed that uncertain information can be generated by the mapping of conflicting attributes to a common domain, based on some domain knowledge. In this paper, we show that uncertain information can also arise when the database integration process requires information not directly represented in the component databases, but can be obtained through some summary of data. We therefore propose an extended relational model based on Dempster-Shafer theory of evidence [2] to incorporate such uncertain knowledge about the source databases. The extended relation uses evidence sets to represent …


The Design Of A Financial Management Database System, Edward G. Leszynski Sep 1996

The Design Of A Financial Management Database System, Edward G. Leszynski

Theses and Dissertations

This research led to the design and development of a financial management database system for the Aeronautical Systems Center (AS C) Environmental Management (EM) Systems Program Office (SPO), which has the responsibility of managing the environmental contracts for the Government-Owned, Contractor-Operated (GOCO) plants that are owned by the Air Force. This thesis investigated the various 'development strategies' and 'methodologies' described in the Management Information Systems literature in order to devise an end-user development strategy capable of meeting the EM SPO's requirements. In addition, the information requirements, conceptual design and prototyping, and procedures phases of the System Development Life Cycle (SDLC) …


Mass Limit For The Standard Model Higgs Boson With The Full Lep I Aleph Data Sample, Buskulic, D.; Et Al., M. Thulasidas Sep 1996

Mass Limit For The Standard Model Higgs Boson With The Full Lep I Aleph Data Sample, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

The reaction e+e− → HZ∗ is used to search for the standard model Higgs boson in the Hνν and the Hℓ+ℓ− channels. The data sample corresponds to about 4.5 million hadronic Z decays collected by the ALEPH experiment at LEP from 1989 to 1995 at centre-of-mass energies at and around the Z peak. Three candidate events are found in the Hμ+μ− channel, in agreement with the expected background from the electroweak process e+e− ℓ+ℓ−qq. This search results in a 95% C.L. lower limit on the Higgs boson mass of 63.9 GeV/c2.


Search For Charginos And Neutralinos With R-Parity Violation At √S = 130 And 136 Gev, Buskulic, D.; Et Al., M. Thulasidas Sep 1996

Search For Charginos And Neutralinos With R-Parity Violation At √S = 130 And 136 Gev, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Searches for charginos and neutralinos produced in e +e - collisions at centre-of-mass energies of 130 and 136 GeV have been performed under the assumptions that R-parity is not conserved, that the dominant R-parity violating coupling involves only leptonic fields, and that the lifetime of the lightest supersymmetric particle can be neglected. In the 5.7 pb -1 data sample collected by ALEPH, no candidate events were found. As a result, chargino and neutralino masses and couplings are constrained and the domains previously excluded at LEP1 are extended.


Strange B Baryon Production And Lifetime In Z Decays, D. Buskulic, M. Thulasidas Sep 1996

Strange B Baryon Production And Lifetime In Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

In a data sample of approximately four million hadronic Z decays recorded with the ALEPH detector from 1990 to 1995, a search for the strange b baryon Ξb is performed with a study of Ξ-lepton correlations. Forty-four events with same sign Ξ−ℓ− combinations are found whereas 8.4 are expected based on the rate of opposite sign Ξ−ℓ+ combinations. This significant excess is interpreted as evidence for Ξb semileptonic decays. The measured product branching ratio is Br(b → Ξb) × Br(Ξb→ XcXℓ−νℓ) × Br(Xc→ Ξ−X′) = (5.4±1.1(stat) ± 0.8(syst)) × 10−4 per lepton species, averaged over electrons and muons, with Xc …


Measurement Of The B Forward-Backward Asymmetry And Mixing Using High-P⊥ Leptons, Buskulic, D., M. Thulasidas Sep 1996

Measurement Of The B Forward-Backward Asymmetry And Mixing Using High-P⊥ Leptons, Buskulic, D., M. Thulasidas

Research Collection School Of Computing and Information Systems

The B0 - B̄0 average mixing parameter χ and b forward-backward asymmetry AFB0(b) are measured from a sample of about 4 200 000 Z → qq̄ events recorded with the ALEPH detector at LEP in the years 1990–1995. High transverse momentum electrons and muons produced in b semileptonic decays provide the tag of the quark flavour and of its charge.The average mixing parameter and the pole b asymmetry are measured to be χ = 0.1246 ± 0.0051stat ± 0.0052syst, AFB0(b) = 0.1008 ± 0.0043stat ± 0.0028syst. The value of sin2θweff = 0.23198 ± 0.00092 is extracted from the asymmetry measurement.


Search For Cp Violation In The Decay Z → B B̄ G, Buskulic, D.; Et Al., M. Thulasidas Sep 1996

Search For Cp Violation In The Decay Z → B B̄ G, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

About three million hadronic decays of the Z collected by ALEPH in the years 1991 to 1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z → bb̄g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, ĥb = ĥAbgVh - ĥVbgAb and hb* = √ĥVb2 + ĥAb2, limits of | ĥb | b*


Observation Of Charmless Hadronic B Decays, Buskulic, D.; Et Al., M. Thulasidas Sep 1996

Observation Of Charmless Hadronic B Decays, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Managing Multiple Information Sources Through Ontologies: Relationship Between Vocabulary Heterogeneity And Loss Of Information, Eduardo Mena, Vipul Kashyap, Arantza Illarramendi, Amit P. Sheth Aug 1996

Managing Multiple Information Sources Through Ontologies: Relationship Between Vocabulary Heterogeneity And Loss Of Information, Eduardo Mena, Vipul Kashyap, Arantza Illarramendi, Amit P. Sheth

Kno.e.sis Publications

The ability to deal with a huge number of independent and heterogeneous repositories is the most critical problem in Global Information Systems. One approach to enable efficient query processing is by utilizing semantic descriptions (organized as ontologies) of such repositories whenever available.

In this context semantic relationships among ontologies can be used Query Processors. Three kind of relationships are considered: synonyms and hypernyms. Using synonyms the semantic of the query is preserved; however, when synonyms are not available and hypernyms or hyponyms are used there exists some loss of information that must be measured.


On Integrating Existing Bibliographic Databases And Structured Databases, Ying Lu, Ee Peng Lim Aug 1996

On Integrating Existing Bibliographic Databases And Structured Databases, Ying Lu, Ee Peng Lim

Research Collection School Of Computing and Information Systems

It is widely accepted that future digital library applications have to be built upon different kinds of database servers to draw different forms of data from them. These data include bibliographic data, text data, multimedia data, and structured data. We address the problem of integrating existing bibliographic and structured databases which reside at different locations in the network. To integrate bibliographic data and structured data, we extended the well-known SQL model to represent bibliographic related attributes and queries. In particular, we have added a new data type to model attributes in the bibliographic database. We have also designed specialized predicates …


Concept Hierarchy Memory Model: A Neural Architecture For Conceptual Knowledge Representation, Learning, And Commonsense Reasoning, Ah-Hwee Tan, Hui-Shin Vivien Soon Jul 1996

Concept Hierarchy Memory Model: A Neural Architecture For Conceptual Knowledge Representation, Learning, And Commonsense Reasoning, Ah-Hwee Tan, Hui-Shin Vivien Soon

Research Collection School Of Computing and Information Systems

This article introduces a neural network based cognitive architecture termed Concept Hierarchy Memory Model (CHMM) for conceptual knowledge representation and commonsense reasoning. CHMM is composed of two subnetworks: a Concept Formation Network (CFN), that acquires concepts based on their sensory representations; and a Concept Hierarchy Network (CHN), that encodes hierarchical relationships between concepts. Based on Adaptive Resonance Associative Map (ARAM), a supervised Adaptive Resonance Theory (ART) model, CHMM provides a systematic treatment for concept formation and organization of a concept hierarchy. Specifically, a concept can be learned by sampling activities across multiple sensory fields. By chunking relations between concepts as …


Libsearch: A Window-Based Frontend To Remote Bibliographic Databases On The Internet, Ee Peng Lim, Soo-Yin Cheng Jul 1996

Libsearch: A Window-Based Frontend To Remote Bibliographic Databases On The Internet, Ee Peng Lim, Soo-Yin Cheng

Research Collection School Of Computing and Information Systems

Over the past several years, a number of wide-area information navigation and discovery tools have been introduced, including WAIS[1], Gopher[2], World-Wide Web[3], etc. In this paper, we describe a graphical query interface to remote bibliographic databases that can be found on the internet. A library query client, called LibSearch, has been designed and implemented using a set of APIs based on Z39.50 protocol standard[4]. Z39.50 is an application-layer protocol within the OSI reference model designed to allow library users to remotely access the bibliographic records in the library systems. As increasing number of OPAC systems are being established as Z39.50 …


Measurement Of The Mass Of The Λb Baryon, Buskulic, D.; Et Al., M. Thulasidas Jul 1996

Measurement Of The Mass Of The Λb Baryon, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Visual Speech Recognition Using Multiple Deformable Lip Models, Devi Chandramohan Jul 1996

Visual Speech Recognition Using Multiple Deformable Lip Models, Devi Chandramohan

Electrical & Computer Engineering Theses & Dissertations

Motivated by the fact that human speech perception is a bimodal process (auditory and visual), several researchers have designed and implemented automatic speech recognition (ASR) systems consisting of both audio and visual subsystems, and shown improved performance relative to traditional purely auditory systems. Several visual speech reading approaches have used deformable templates to model the shape of a speaker's lips. Deformable templates are models of image objects, which can be deformed by adjusting a set of parameters to match the object in some optimal way, as defined by a cost function. Using a single deformable lip model has disadvantages such …