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Articles 6511 - 6540 of 6717

Full-Text Articles in Physical Sciences and Mathematics

Observer: An Approach For Query Processing In Global Information Systems Based On Interoperation Across Pre-Existing Ontologies, Eduardo Mena, Vipul Kashyap, Amit P. Sheth, Arantza Illarramendi Jun 1996

Observer: An Approach For Query Processing In Global Information Systems Based On Interoperation Across Pre-Existing Ontologies, Eduardo Mena, Vipul Kashyap, Amit P. Sheth, Arantza Illarramendi

Kno.e.sis Publications

The huge number of autonomous and heterogeneous data repositories accessible on the “global information infrastructure” makes it impossible for users to be aware of the locations structure/organization, query languages and semantics of the data in various repositories. There is a critical need to complement current browsing, navigational and information retrieval techniques with a strategy that focuses on information content and semantics. In any strategy that focuses on information content, the most critical problem is that of different vocabularies used to describe similar information across domains. We discuss a scalable approach for vocabulary sharing. The objects in the repositories are represented …


Study Of The B0sb0s Oscillation Frequency Using D-S ℓ+ Combinations In Z Decays, Buskulic, D.; Et Al., M. Thulasidas Jun 1996

Study Of The B0sb0s Oscillation Frequency Using D-S ℓ+ Combinations In Z Decays, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

A lower limit on the oscillation frequency of the B s 0 B s 0 system is obtained from approximately four million hadronic Z decays accumulated using the ALEPH detector at LEP from 1991 to 1995. Leptons are combined with opposite sign D s − candidates reconstructed in seven different decay modes as evidence of semileptonic B s 0 decays. Criteria designed to ensure precise proper time reconstruction select 277D s − ℓ + combinations. The initial state of these B s 0 candidates is determined using an algorithm optimized to efficiently utilise the tagging information available for each event. …


Measurement Of Hadron And Lepton-Pair Production From E+E- Annihilation At Centre-Of-Mass Energies Of 130 And 136 Gev, Buskulic, D.; Et Al., M. Thulasidas Jun 1996

Measurement Of Hadron And Lepton-Pair Production From E+E- Annihilation At Centre-Of-Mass Energies Of 130 And 136 Gev, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.


Specifying Object-Oriented Federated Database From Existing Databases, Ee Peng Lim, M. L. Lim, J. Srivastava Jun 1996

Specifying Object-Oriented Federated Database From Existing Databases, Ee Peng Lim, M. L. Lim, J. Srivastava

Research Collection School Of Computing and Information Systems

In this paper, we present a mapping strategy that is based on a proposed set of DB integration operations. We first define an OO federated DB as a virtual view on multiple OO export DBs. Our DB mapping strategy systematically derives each of the class extents, deep class extents and relationships of the federated DB using an operator tree consisting of the integration operations. This mapping approach differs from the other existing approaches in that it is algebraic based, and is therefore very suitable for implementing federated query processing.


Towards Designing A Knowledge-Based Tutoring System : Sql-Tutor As An Example, Gang Zhou May 1996

Towards Designing A Knowledge-Based Tutoring System : Sql-Tutor As An Example, Gang Zhou

Dissertations

A Knowledge-Based Tutoring System, also sometimes called an Intelligent Tutoring System, is a computer based instructional system that uses artificial intelligence techniques to help people learn some subject. The goal of the system is to provide private tutoring to its students based on their different backgrounds, requests, and interests. The system knows what subject materials it should teach, when and how to teach them, and can diagnose the mistakes made by the students and help them correct the mistakes.

The major objective of this dissertation is to investigate and develop a generic framework upon which we can build a Knowledge-Based …


Pattern Discovery In Sequence Databases : Algorithms And Applications To Dna/Protein Classification, Gung-Wei Chirn May 1996

Pattern Discovery In Sequence Databases : Algorithms And Applications To Dna/Protein Classification, Gung-Wei Chirn

Dissertations

Sequence databases comprise sequence data, which are linear structural descriptions of many natural entities. Approximate pattern discovery in a sequence database can lead to important conclusions or prediction of new phenomena. Traditional database technology is not suitable for accomplishing the task, and new techniques need to be developed.

In this dissertation, we propose several new techniques for discovering patterns in sequence databases. Our techniques incorporate pattern matching algorithms and novel heuristics for discovery and optimization. Experimental results of applying the techniques to both generated data and DNA/proteins show the effectiveness of the proposed techniques.

We then develop several classifiers using …


Proof Strategies For Hardware Verification, Robert Eastham, Krishnaprasad Thirunarayan May 1996

Proof Strategies For Hardware Verification, Robert Eastham, Krishnaprasad Thirunarayan

Kno.e.sis Publications

Ascertaining correctness of digital hardware designs through simulation does not scale-up for large designs because of the sheer combinatorics of the problem. Formal verification of hardware designs holds promise because its computational complexity is of the order of number of different types of components (and not number of components in the design). This approach requires the specification of the behavior and the design in a formal language, and reason with them using a theorem prover. In this paper we attempt to develop a methodology for writing and using these specifications for some important classes of hardware circuits. We examine digital …


The Quest For The Gnarl, Rudy Rucker May 1996

The Quest For The Gnarl, Rudy Rucker

SWITCH

The article describes some of the author’s own image-generating computer programs that he describes as “gnarly”. He began writing a simple spirograph program based off simple sine wave function called Spiro. Later transitioned into writing with C and better programs using more nonlinear feedback. Where Spiro is based on a simple sine wave function, Vine uses a nested sine function: the sine of the sine. The need for a more complicated computational approach lead to iteration and parallelism. Julgnarl uses Iteration and Calife uses parallelism. Calife shows one-dimensional cellular automata: spaces in which virtual computers are lined up like beads …


How I Got Gnarly, Rudy Rucker May 1996

How I Got Gnarly, Rudy Rucker

SWITCH

The article describes how Rudy Rucker’s curious interest in celluar automata led to his career in mathematical computer science at San José State University. After conducting interviews on the theory of cellular automata as a freelance writer, he felt compelled to be involved in this great intellectual revolution in computer-aided experimental mathematics. Committed to reinventing himself, Rucker's interactions with mathematicians inspired him to write “Mind Tools”, a book that surveys mathematics from the standpoint that is information. After publishing his book, in 1987, he was eventually offered a position at SJSU in the Mathematics and Computer Science department. With assistance …


Gnarly Rantings About The Hacker And The Ants, Rudy Rucker May 1996

Gnarly Rantings About The Hacker And The Ants, Rudy Rucker

SWITCH

The article is an excerpt from Rucker’s book “The Happy Mutant”. It begins with his reflection of his career with GoMotion. He discusses the relation that he saw between design and cyberspace. Later he discusses his experience with a game a colleague found on the net: a virtual world where player is an ant. He talks about the struggles he goes through in this virtual world because of game difficulty and poor visuals. He ties it all in with how the Silicon Valley works in a similar way, and is filled with hackers and programers all needing each other to …


A System For Structured Management Of Hypermedia Resources For The World Wide Web, Kevin L. Marlowe Mar 1996

A System For Structured Management Of Hypermedia Resources For The World Wide Web, Kevin L. Marlowe

Computer Science Theses & Dissertations

The World Wide Web (WWW) is arguably the preferred method for disseminating information across the Internet. Most of the work to support the advancement of WWW technology has focused on servers used in storing and retrieving information, browsers for viewing this information, and editors or filters for creating the information.

One area which has received little attention is that of actually managing this information at the local host. This thesis describes the development of a means for organizing local data prior to its publishing on the WWW, a method for gathering local pages together and preparing them for distribution, and …


A Precise Measurement Of The Average B Hadron Lifetime, D. Buskulic, M. Thulasidas Feb 1996

A Precise Measurement Of The Average B Hadron Lifetime, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

An improved measurement of the average b hadron lifetime is performed using a sample of 1.5 million hadronic Z decays, collected during the 1991–1993 runs of ALEPH, with the silicon vertex detector fully operational. This uses the three-dimensional impact parameter distribution of lepton tracks coming from semileptonic b decays and yields an average b hadron lifetime of 1.533 ± 0.013 ± 0.022 ps.


Entity Identification In Database Integration, Ee Peng Lim, Jaideep Srivastava, Satya Prabhakar, James Richardson Feb 1996

Entity Identification In Database Integration, Ee Peng Lim, Jaideep Srivastava, Satya Prabhakar, James Richardson

Research Collection School Of Computing and Information Systems

The objective of entity identification is to determine the correspondence between objective instances from more than one database. This paper examines the problem at the instance level assuming that schema level heterogeneity has been resolved a priori. Soundness and completeness are defined as the desired properties of any entity-identification technique. To achieve soundness, a set of identity and distinctness rules have to be established for the entities in the integrated world. We then propose the use of extended key, which is the union of keys (and possibly other attributes) from the relations to be matched, and its corresponding identity rule …


Spieltheorie, Alexander Chocholaty, Pascal Hitzler Jan 1996

Spieltheorie, Alexander Chocholaty, Pascal Hitzler

Computer Science and Engineering Faculty Publications

No abstract provided.


Semantic And Schematic Similarities Between Database Objects: A Context-Based Approach, Vipul Kashyap, Amit P. Sheth Jan 1996

Semantic And Schematic Similarities Between Database Objects: A Context-Based Approach, Vipul Kashyap, Amit P. Sheth

Kno.e.sis Publications

In a multidatabase system, schematic conflicts between two objects are usually of interest only when the objects have some semantic similarity. We use the concept of semantic proximity, which is essentially an abstraction/mapping between the domains of the two objects associated with the context of comparison. An explicit though partial context representation is proposed and the specificity relationship between contexts is defined. The contexts are organized as a meet semi-lattice and associated operations like the greatest lower bound are defined. The context of comparison and the type of abstractions used to relate the two objects form the basis of a …


Syllogism Solving Under Time Pressure, Gondy Leroy, Koen Lamberts Jan 1996

Syllogism Solving Under Time Pressure, Gondy Leroy, Koen Lamberts

CGU Faculty Publications and Research

No abstract provided.


Rex ' 96 : An Expert Guide To Revegetation, David Bicknell Jan 1996

Rex ' 96 : An Expert Guide To Revegetation, David Bicknell

Journal of the Department of Agriculture, Western Australia, Series 4

Agriculture Western Australia has provided coordination and technical input to a powerful source of information on plants for Australian conditions. David Bicknell outlines some of its features and uses.

Farmers, local government, advisers and even gardeners often have trouble finding the right plant for the right place for a given purpose. Rather than spend a lot of time, money and effort looking through scattered sources of information, many people stick with a limited number of species year after year. This neglects plants that may be much better suited to the purpose, and also fails to develop Australia's huge range of …


Measurement Of The Λb Polarization In Z Decays, Buskulic, D.; Et Al., M. Thulasidas Jan 1996

Measurement Of The Λb Polarization In Z Decays, Buskulic, D.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

The Λb polarization in hadronic Z decays is measured in semileptonic decays from the average energies of the charged lepton and the neutrino. In a data sample of approximately 3 million hadronic Z decays collected by the ALEPH detector at LEP between 1991 and 1994, 462 ± 31 Λb candidates are selected using (Λπ+)-lepton correlations. From this event sample, the Λb polarization is measured to be PΛb = −0.23−0.20+0.24(stat.)−0.07+0.08(syst.).


Improved Measurement Of The B0 And B+ Meson Lifetimes, D. Buskulic, M. Thulasidas Jan 1996

Improved Measurement Of The B0 And B+ Meson Lifetimes, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

Updated measurements of the B0 and B+ meson lifetimes are presented. From a data sample of 1.72 million hadronic Z0 decays recorded during the period 1991 to 1993, a sample of approximately 1000 semileptonic B meson decays containing a D0, D+ or D*+ has been isolated. From the distribution of decay times in the different samples the lifetimes of the B0 and B+ mesons are determined to be 1.53±0.12±0.08 ps and 1.52±0.14±0.09 ps, respectively, where the first error is statistical and the second systematic. The ratio of the B+ to B0 lifetimes is measured to be 0.99±0.14+0.05−0.04, confirming expectations that …


Customer Feedback Information System For Quality Improvement, Ke Wang Jan 1996

Customer Feedback Information System For Quality Improvement, Ke Wang

Masters Theses

This research addressed the basic needs for an effective customer feedback information system and the database technology to develop the system. It discussed the system concept and configuration of a typical customer feedback information system, database management technology, programming flow charts, program functions and capabilities. A proposed customer feedback information system consists of customer data inputs, database management system and outputs to various departments in an organization. With a user-friendly interface, database management system serves as an information management tool. It can process the feedback from customers and use the information in decision making. Thus, customer feedback can be promptly …


A Formal Preparation For Object-Oriented Query Optimisation, Catherine Higgins Jan 1996

A Formal Preparation For Object-Oriented Query Optimisation, Catherine Higgins

Articles

This paper describes work that is in progress on a formalised preparation to object-oriented query optimisation. Such preparation is conducive to the development of optimisation strategies. As an example of a formal preparation, this paper presents a formalised object algebra, a suggested optimisation method and an implementation of an algebraic converter suitable for DAPLEX.


Determination Of Sin2Θw Eff Using Jet Charge Measurements In Hadronic Z Decays, D. Buskulic, M. Thulasidas Jan 1996

Determination Of Sin2Θw Eff Using Jet Charge Measurements In Hadronic Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The electroweak mixing angle is determined with high precision from measurements of the mean difference between forward and backward hemisphere charges in hadronic decays of the Z. A data sample of 2.5 million hadronic Z decays recorded over the period 1990 to 1994 in the ALEPH detector at LEP is used. The mean charge separation between event hemispheres containing the original quark and antiquark is measured forbb¯bb¯ andcc¯cc¯ events in subsamples selected by their long lifetimes or using fastD*’s. The corresponding average charge separation for light quarks is measured in an inclusive sample from the anticorrelation between charges of opposite …


Tau Hadronic Branching Ratios, D. Buskulic, M. Thulasidas Jan 1996

Tau Hadronic Branching Ratios, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

From 64492 selected τ-pair events, produced at the Z0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and π0s, and the removal of fake photons. A detailed study of the systematics entering the π0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test τ-μ, universality in …


Tau Leptonic Branching Ratios, D. Buskulic, M. Thulasidas Jan 1996

Tau Leptonic Branching Ratios, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

A sample of 62249 τ-pair events is selected from data taken with the ALEPH detector in 1991, 1992 and 1993. The measurement of the branching fractions for τ decays into electrons and muons is presented with emphasis on the study of systematic effects from selection, particle identification and decay classification. The results obtained are: B e = 17.79±0.12(stat)±0.06(syst)(%) and Bμ = 17.31±0.11(stat)±0.05(syst)(%). Combined with the most recent ALEPH determination of the τ lifetime, these results provide a relative measurement of the leptonic couplings in the weak charged current for transverse W bosons: ${cal G}_{ώ}/{cal G}_{e}=1.0002pm 0.0051$ and ${cal G}_{∢u}/{cal G}_{u}=0.9943pm …


Simulation Modeling Within Workflow Technology, John A. Miller, Amit P. Sheth, Krzysztof J. Kochut, Xuzhong Wang, Arun Murugan Dec 1995

Simulation Modeling Within Workflow Technology, John A. Miller, Amit P. Sheth, Krzysztof J. Kochut, Xuzhong Wang, Arun Murugan

Kno.e.sis Publications

This paper presents an approach for integrating simulation modeling and analysis capabilities within the workflow management system (WFMS) being developed in the Large Scale Distributed Information Systems (LSDIS) Lab at the University of Georgia. Simulation modeling can be used for studying the efficiency of workflow designs as well as studying the general performance and reliability of WFMSs. We also discuss the importance of using sophisticated monitoring and animation capabilities, and the use of workflow management technology to advance simulation technology itself. Finally, we demonstrate a sample simulation where tasks and task managers are simulated.


On The Equivalence Of Upward And Downward Inheritance Reasoners, Krishnaprasad Thirunarayan Nov 1995

On The Equivalence Of Upward And Downward Inheritance Reasoners, Krishnaprasad Thirunarayan

Kno.e.sis Publications

In this paper, we analyze systematically the downward (property flow) and the upward (individual flow) views of inheritance for different categories of inheritance networks. We observe that both these views assign the same meaning to tree-structured hierarchies, and explain the divergence in the interpretation of more general networks in terms of their expressive power. This simple analysis sheds light on the inherent nature of nonmonotonic inheritance and can form the basis for the design of efficient algorithms for certain classes of queries. In addition, we describe the notion of preferential inheritance to specify additional conflict resolution information that can be …


Quality Of Service Specification For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier Nov 1995

Quality Of Service Specification For Multimedia Presentations, Richard Staehli, Jonathan Walpole, David Maier

Computer Science Faculty Publications and Presentations

The bandwidth limitations of multimedia systems force tradeoffs between presentation data fidelity and real-time performance. For example, digital video is commonly encoded with lossy compression to reduce bandwidth and frames may be skipped during playback to maintain synchronization. These tradeoffs depend on device performance and physical data representations that are hidden by a database system. If a multimedia database is to support digital video and other continuous media data types, we argue that the database should provide a Quality of Service (QOS) interface to allow application control of presentation timing and information loss tradeoffs.

This paper proposes a data model …


Measurement Of The Bs0 Lifetime And Production Rate With Ds- ℓ+ Combinations In Z Decays, D. Buskulic, M. Thulasidas Nov 1995

Measurement Of The Bs0 Lifetime And Production Rate With Ds- ℓ+ Combinations In Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

A precise determination of the effective Bs0→K+K− lifetime can be used to constrain contributions from physics beyond the Standard Model in the Bs0 meson system. Conventional approaches select B meson decay products that are significantly displaced from the B meson production vertex. As a consequence, B mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0fb−1 of data recorded by the LHCb experiment, the effective Bs0→K+K− lifetime is …


Air Force Materiel Command (Afmc) Modeling, Simulation, And Analysis (Ms&A) Interactive Database, Timothy J. Wagner Sep 1995

Air Force Materiel Command (Afmc) Modeling, Simulation, And Analysis (Ms&A) Interactive Database, Timothy J. Wagner

Theses and Dissertations

This study develops a high level, unifying taxonomy for Modeling, Simulation, and Analysis (MS&A) products for the Air Force Materiel Command (AFMC). AFMC is concerned that limited resources are being expended on duplicative MS&A efforts. No mechanism exists that would confirm or deny this concern, so it was suggested that a database could be developed to catalog and track AFMC's MS&A inventory. First, it was necessary to determine the information that a decision maker needs to select a suitable MS&A product. Potential traits and characteristics were identified through review of current regulatory guidance, interviews with MS&A users, and a study …


Measurement Of Αs From Scaling Violations In Fragmentation Functions In E+E- Annihilation, D. Buskulic, Manoj Thulasidas Sep 1995

Measurement Of Αs From Scaling Violations In Fragmentation Functions In E+E- Annihilation, D. Buskulic, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

A study of scaling violations in fragmentation functions performed by the ALEPH collaboration at LEP is presented.