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An Intelligent Editor For Natural Language Processing Of Unrestricted Text, Demetrios George Glinos Jan 1999

An Intelligent Editor For Natural Language Processing Of Unrestricted Text, Demetrios George Glinos

Retrospective Theses and Dissertations

The understanding of natural language by computational methods has been a continuing and elusive problem in artificial intelligence. In recent years there has been a resurgence in natural language processing research. Much of this work has been on empirical or corpus-based methods which use a data-driven approach to train systems on large amounts of real language data. Using corpus-based methods, the performance of part-of-speech (POS) taggers, which assign to the individual words of a sentence their appropriate part of speech category (e.g., noun, verb, preposition), now rivals human performance levels, achieving accuracies exceeding 95%. Such taggers have proved useful as …

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One-Prong Τ Decays With Kaons, R. Barate, M. Thulasidas Jan 1999

One-Prong Τ Decays With Kaons, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

One-prong ττ decays into final states involving kaons are studied with about 161 000 τ+τ−τ+τ− events collected by the ALEPH detector from 1991 to 1995. Charged kaons are identified by dE/dx measurement, while K0LKL0's are detected through their interaction in calorimeters. Branching ratios are measured for the inclusive mode, B(τ−→K−Xντ)=(1.52±0.04±0.04)%B(τ−→K−Xντ)=(1.52±0.04±0.04)%, where X can be any system of neutral particles, and for the exclusive modesB(τ−→K−ντ)=(6.96±0.25±0.14)×10−3,B(τ−→K−π0ντ)=(4.44±0.26±0.24)×10−3,B(τ−→K−π0π0ντ)=(0.56±0.20±0.15)×10−3,B(τ−→K−π0π0π0ντ)=(0.37±0.21±0.11)×10−3,B(τ−→K−K0ντ)=(1.62±0.21±0.11)×10−3,B(τ−→K−K0π0ντ)=(1.43±0.25±0.15)×10−3,B(τ−→K0¯¯¯¯¯¯¯π−ντ)=(9.28±0.45±0.34)×10−3,B(τ−→K0¯¯¯¯¯¯¯π−π0ντ)=(3.47±0.53±0.37)×10−3,B(τ−→K−ντ)=(6.96±0.25±0.14)×10−3,B(τ−→K−π0ντ)=(4.44±0.26±0.24)×10−3,B(τ−→K−π0π0ντ)=(0.56±0.20±0.15)×10−3,B(τ−→K−π0π0π0ντ)=(0.37±0.21±0.11)×10−3,B(τ−→K−K0ντ)=(1.62±0.21±0.11)×10−3,B(τ−→K−K0π0ντ)=(1.43±0.25±0.15)×10−3,B(τ−→K0¯π−ντ)=(9.28±0.45±0.34)×10−3,B(τ−→K0¯π−π0ντ)=(3.47±0.53±0.37)×10−3,where the first error is statistical and the second is systematical. Upper limits for B(τ−→K0¯¯¯¯¯¯¯π−π0π0ντ)B(τ−→K0¯π−π0π0ντ) and B(τ−→K−K0π0π0ντ)B(τ−→K−K0π0π0ντ) are also obtained. Mass spectra in the final states are investigated in order to study the relevant dynamics.

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Search For Bs0 Oscillations Using Inclusive Lepton Events, R. Barate, M. Thulasidas Jan 1999

Search For Bs0 Oscillations Using Inclusive Lepton Events, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A search for B0sBs0 oscillations is performed using a sample of semileptonic b-hadron decays collected by the ALEPH experiment during 1991–95. Compared to previous inclusive lepton analyses, the proper time resolution and b-flavour mistag rate are significantly improved. Additional sensitivity to B0sBs0 mixing is obtained by identifying subsamples of events having a B0sBs0 purity which is higher than the average for the whole data sample. Unbinned maximum likelihood amplitude fits are performed to derive a lower limit of Δms>9.5ps−1Δms>9.5ps−1 at the 95% confidence limit (95% CL). Combining with the ALEPH D−sDs−-based analyses yields Δms>9.6ps−1Δms>9.6ps−1 at 95% …

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Training Methods For Shunting Inhibitory Artificial Neural Networks, Son Lam Phung Jan 1999

Training Methods For Shunting Inhibitory Artificial Neural Networks, Son Lam Phung

Theses : Honours

This project investigates a new class of high-order neural networks called shunting inhibitory artificial neural networks (SIANN's) and their training methods. SIANN's are biologically inspired neural networks whose dynamics are governed by a set of coupled nonlinear differential equations. The interactions among neurons are mediated via a nonlinear mechanism called shunting inhibition, which allows the neurons to operate as adaptive nonlinear filters. The project's main objective is to devise training methods, based on error backpropagation type of algorithms, which would allow SIANNs to be trained to perform feature extraction for classification and nonlinear regression tasks. The training algorithms developed will …

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Implementing Flexible Software Techniques In A 4gl Environment, Stephen O'Connor Jan 1999

Implementing Flexible Software Techniques In A 4gl Environment, Stephen O'Connor

Theses : Honours

Today more IT professionals arc employed on the maintenance of existing software applications than are employed to develop new systems. Why is there such a need for this maintenance? Part of the problem is that developers have traditionally seen system requirements as fixed from the time they have been 'signed off. In reality requirements arc dynamic and subject to change as an organisation's environment changes. Flexible software techniques recognise that software requirements are subject to future changes. Flexibility is seen as an important design goal criterion with "true" or "strong" flexibility implying that an application's behaviour can be altered without …

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Adaptive Information Filtering: Improvement Of The Matching Technique And Derivation Of The Evolutionary Algorithm, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper Jan 1999

Adaptive Information Filtering: Improvement Of The Matching Technique And Derivation Of The Evolutionary Algorithm, Daniel R. Tauritz, Ida G. Sprinkhuizen-Kuyper

Computer Science Faculty Research & Creative Works

Adaptive Information Filtering is concerned with filtering information streams in changing environments. The changes may occur both on the transmission side (the nature of the streams can change) and on the reception side (the interests of a user can change). The research described in this report details the progress made in a prototype Adaptive Information Filtering system based on weighted trigram analysis and evolutionary computation. The main improvements of the algorithms employed by the system concern the computation of the distance between weighted trigram vectors and a further analysis of the two-pool evolutionary algorithm. We tested our new prototype system …

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Benchmarking Financial Operations Using The Premier Operations Outlook Database, Margaret M. Thompson Jan 1999

Benchmarking Financial Operations Using The Premier Operations Outlook Database, Margaret M. Thompson

Community & Environmental Health Theses & Dissertations

Acute-care hospitals have come under increased pressure to reduce costs while increasing the quality of providing care. Historically, increasing costs of providing care has had the greatest impact on the reduction of operating margins necessary to expand capital and for repayment of debt. Facilities can benchmark internal historical data to identify areas where costs have increased and are able to explain the factors that contribute to the increases. One of the challenges facing hospitals in their efforts to reduce operating costs is how, what, and where, do they obtain comparative data to benchmark the cost of operating medical facility to …

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A 2d Dwt Architecture Suitable For The Embedded Zerotree Wavelet Algorithm, James Martinez Jan 1999

A 2d Dwt Architecture Suitable For The Embedded Zerotree Wavelet Algorithm, James Martinez

Theses : Honours

Digital Imaging has had an enormous impact on industrial applications such as the Internet and video-phone systems. However, demand for industrial applications is growing enormously. In particular, internet application users are, growing at a near exponential rate. The sharp increase in applications using digital images has caused much emphasis on the fields of image coding, storage, processing and communications. New techniques are continuously developed with the main aim of increasing efficiency. Image coding is in particular a field of great commercial interest. A digital image requires a large amount of data to be created. This large amount of data causes …

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Applications Of Advanced Software Techniques To Internet And Www Server Development, John A. Brosnan Jan 1999

Applications Of Advanced Software Techniques To Internet And Www Server Development, John A. Brosnan

Theses

We are living in an information age. Never before has so much data been globally available and instantaneously accessible. The main reason for this revolution is the arrival of the Internet; or perhaps more accurately, the World Wide Web(WWW). This thesis discusses the development of Internet and WWW servers and the latest Web technologies including Java, CORBA and Object Databases. It presents the fundamental concepts of server development and aims to study in particular dynamic WWW servers providing multimedia content. From the viewpoint of interoperability, the CORBA multimedia standard is reviewed. The various mechanisms of data storage and retrieval for …

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Development Of A Model For Smart Card Based Access Control In Multi-User, Multi-Resource, Multi-Level Access Systems, David Shaw Jan 1999

Development Of A Model For Smart Card Based Access Control In Multi-User, Multi-Resource, Multi-Level Access Systems, David Shaw

Theses: Doctorates and Masters

The primary focus of this research is an examination of the issues involved in the granting of access in an environment characterised by multiple users, multiple resources and multiple levels of access permission. Increasing levels of complexity in automotive systems provides opportunities for improving the integration and efficiency of the services provided to the operator. The vehicle lease / hire environment provided a basis for evaluating conditional access to distributed, mobile assets where the principal medium for operating in this environment is the Smart Card. The application of Smart Cards to existing vehicle management systems requires control of access to …

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Nonlinear Constrained Optimizer And Parallel Processing For Golden Block Line Search, Duc T. Nguyen, Wilson H. Tang, Yeou K. Tung, Hakizumwami B. Runesha Jan 1999

Nonlinear Constrained Optimizer And Parallel Processing For Golden Block Line Search, Duc T. Nguyen, Wilson H. Tang, Yeou K. Tung, Hakizumwami B. Runesha

Civil & Environmental Engineering Faculty Publications

Generalized exponential penalty functions are constructed for the multiplier methods in solving nonlinear programming problems. The non-smooth extreme constraint Gext is replaced by a single smooth constraint Gs by using the generalized exponential function (base a>1). The well-known K.S. function is found to be a special case of our proposed formulation. Parallel processing for Golden block line search algorithm is then summarized, which can also be integrated into our formulation. Both small and large-scale nonlinear programming problems (up to 2000 variables and 2000 nonlinear constraints) have been solved to validate the proposed algorithms.

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Developing Database Applications By Using Software Components, Nusret Conk Jan 1999

Developing Database Applications By Using Software Components, Nusret Conk

College of Graduate Studies: Theses & Dissertations (1964–2006)

Today, the software application development process is more assembly work than a "build from scratch" approach. By placing pre-existing software components together, it is possible to create a complete application. Such components provide interfaces so that programs use them for their intended purposes. The objective of this thesis is to illustrate how software components work together to make a complete application. To illustrate the ideas and the components, this project presents a three-tiered web database application. This application, as a whole, is made up of the client side web browser, a database and the actual application programs which are Java …

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Light Aircraft Management System, Evan Karjalainen Jan 1999

Light Aircraft Management System, Evan Karjalainen

Theses : Honours

This report details methods to construct a flight data logging system that can be used to manage student flight and aircraft maintenance records. These methods utilise GPS, embedded processors and associated software to depict the occurrence of landings, "Touch and Goes" and record aircraft total flight time. By manipulating these methods it was possible to produce a usable data-logging unit which facilitated the automation of flight maneuver recording. This datatogging unit was constructed from embedded components and interfaced with a user defined database. Perusal of the details within should provide the reader with a clear understanding of the tasks involved …

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Software Quality Function Deployment : A Method For Building Better Software, Dean Carruthers Jan 1999

Software Quality Function Deployment : A Method For Building Better Software, Dean Carruthers

Theses : Honours

In recent years it is becoming increasingly more apparent that quality even more than productivity is emerging as the key issue in the development of software. The quality systems currently employed by most software companies however arc simply not up to the task, traditional quality systems focus upon conformance to company standards, automation to eliminate human error and in some cases quality improvement teams. These traditional quality assurance methods lead to quality as defined from the organizations point of view, all work performed is done to their standards, however a what it is that makes a quality product is defined …

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Distributed Artificial Intelligence In A Virtual Reality Setting: A Case Study, Rebecca Lohr Jan 1999

Distributed Artificial Intelligence In A Virtual Reality Setting: A Case Study, Rebecca Lohr

Presidential Scholars Theses (1990 – 2006)

Artificial intelligence, or Al, is a fascinating area of research. Al refers to the attempt to create a computer program, known as an intelligent agent, which can "think" and operate in a complex, changing environment. Many problems have been discovered in attempting to develop these intelligent agents, including the simulation of learning, planning, and natural language understanding. While researching these issues, a new branch of Al research has developed. Researchers discovered that there are other problems associated with how intelligent agents work together to solve problems. This field of research has become known as distributed artificial intelligence, or DAI.

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Reconfigurable Shift Switching Parallel Comparators, R. Lin, S. Olariu Jan 1999

Reconfigurable Shift Switching Parallel Comparators, R. Lin, S. Olariu

Computer Science Faculty Publications

We present novel asynchronous VLSI comparator schemes which are based on recently proposed reconfigurable shift switch logic and the traditional (precharged) CMOS domino logic. The schemes always produce a semaphore as a by-product of the process to indicate the end of domino process, which requires no additional delay and a minimal number of additional devices. For a large percentage of inputs the computations are much faster than traditional synchronous comparators due to the full utilization of the inherent speed of the circuits. Also the schemes are simple, area compact and stable.

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Feedback Based Dynamic Proportion Allocation For Disk I/O, Dan Revel, Dylan Mcnamee, Calton Pu, David Steere, Jonathan Walpole Jan 1999

Feedback Based Dynamic Proportion Allocation For Disk I/O, Dan Revel, Dylan Mcnamee, Calton Pu, David Steere, Jonathan Walpole

Computer Science Faculty Publications and Presentations

In this paper we propose to use feedback control to automatically allocate disk bandwidth in order to match the rate of disk I/O to the real-rate needs of applications. We describe a model for adaptive resource management based on measuring the relative progress of stages in a producer-consumer pipeline. We show how to use prefetching to transform a passive disk into an active data producer whose progress can be controlled via feedback. Our progress-based framework allows the integrated control of multiple resources. The resulting system automatically adapts to varying application rates as well as to varying device latencies.

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Transition From Research To Operations: Arktos - A Knowledge-Based Sea Ice Classification System, Cheryl Bertoia, Denise Gineris, Kim Partington, Leen-Kiat Soh, Costas Tsatsoulis Jan 1999

Transition From Research To Operations: Arktos - A Knowledge-Based Sea Ice Classification System, Cheryl Bertoia, Denise Gineris, Kim Partington, Leen-Kiat Soh, Costas Tsatsoulis

School of Computing: Conference and Workshop Papers

ARKTOS is a fully automated intelligent system that classifies sea ice and that is now being used by the U.S. National Ice Center (NIC) for daily operations related to the NIC’s task of mapping the ice covered oceans. In this paper we describe the process of taking a research project and transitioning it to an operational environment. We discuss the theoretical methodologies implemented in ARKTOS, and how ARKTOS was developed, tested, and finally moved to operations.

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A Synthesis For Testability Scheme For Finite State Machines Using Clock Control, Kent L. Einspahr, Shashank K. Mehta, Sharad C. Seth Jan 1999

A Synthesis For Testability Scheme For Finite State Machines Using Clock Control, Kent L. Einspahr, Shashank K. Mehta, Sharad C. Seth

School of Computing: Faculty Publications

A new method is proposed for improving the testability of a finite state machine (FSM) during its synthesis. The method exploits clock control to enhance the controllability and observability of machine states. With clock control it is possible to add new state transitions during testing. Therefore, it is easier to navigate between states in the resulting test machine. Unlike prior work, where clock control is added to the circuit as a postdesign step, here, clock control is considered in conjunction with a symbolic scheme for encoding the states of the FSM. The encoding is shown to result in significant reductions …

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Camera Trackers, Matthew Cutts Jan 1999

Camera Trackers, Matthew Cutts

Link Foundation Modeling, Simulation and Training Fellowship Reports

Tracking an object's location with inertial sensors works well over short time periods, but sensor drift and errors in integration cause errors to accumulate exponentially. Images, in contrast, work very well to determine a camera's location provided that the camera moves slowly. I received fellowship funding to work on a hybrid image and inertial tracker. The idea was to use data from the image sensors to correct errors and drift in the inertial sensors. The computer vision community has expended a great deal of energy in pursuing motion tracking from images. This area of research is also related to compositing …

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Spatially Augmented Reality, Ramesh Raskar Jan 1999

Spatially Augmented Reality, Ramesh Raskar

Link Foundation Modeling, Simulation and Training Fellowship Reports

To create an effective illusion of virtual objects coexisting with the real world, see-through HMD-based Augmented Reality techniques supple1nent the user's view with images of virtual objects. We introduce here a new paradigm, Spatially Augmented Reality (SAR), where virtual objects are rendered directly within or on the user's physical space. A key benefit of SAR is that the user does not need to wear a head-mounted display. Instead, with the use of spatial displays, wide field of view and possibly high-resolution images of virtual objects can be integrated directly into the environ1nent. For example, the virtual objects can be realized …

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Determination Of The Lep Centre-Of-Mass Energy From Zγ Events, R. Barate, Manoj Thulasidas Jan 1999

Determination Of The Lep Centre-Of-Mass Energy From Zγ Events, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

A study of events with photons and missing energy has been performed with the data sample obtained with the ALEPH detector at centre-of-mass energies from 161 to 184 GeV, corresponding to a total integrated luminosity of about 80 pb−1. The measured distributions are in agreement with Standard Model predictions, leading to constraints on WWγ gauge coupling parameters ∆κγ and λγ. The results from the fit to the cross sections and to the energy and angular distributions of the photons are: ∆κγ = 0.05+1.15 −1.10(stat)±0.25(syst) λγ = −0.05+1.55 −1.45(stat)±0.30(syst).

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Monitoring The Stability Of The Aleph Vertex Detector, G. Sguazzoni, Manoj Thulasidas Jan 1999

Monitoring The Stability Of The Aleph Vertex Detector, G. Sguazzoni, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The ALEPH Silicon Vertex Detector features an optical fibre laser system to monitor its mechanical stability. The operating principle and the general performance of the laser system are described. The experience obtained during 1997 and 1998 operations confirms the important role that such a system can have with respect to the detector alignment requirements. In particular, the laser system has been used to monitor short-term temperature-related effects and long-term movements. These results and a description of the laser-based alignment correction applied to the 1998 data are presented.

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Weighting Unusual Feature Types, Nicholas Howe, Claire Cardie Jan 1999

Weighting Unusual Feature Types, Nicholas Howe, Claire Cardie

Computer Science: Faculty Publications

Feature weighting is known empirically to improve classification accuracy for k-nearest neighbor classifiers in tasks with irrelevant features. Many feature weighting algorithms are designed to work with symbolic features, or numeric features, or both, but cannot be applied to problems with features that do not fit these categories. This paper presents a new k-nearest neighbor feature weighting algorithm that works with any kind of feature for which a distance function can be defined. Applied to an image classification task with unusual set-like features, the technique improves classification accuracy significantly. In tests on standard data sets from the UCI repository, the …

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Harp: A Distributed Query System For Legacy Public Libraries And Structured Databases, Ee Peng Lim, Ying Lu Jan 1999

Harp: A Distributed Query System For Legacy Public Libraries And Structured Databases, Ee Peng Lim, Ying Lu

Research Collection School Of Computing and Information Systems

The main purpose of a digital library is to facilitate users easy access to enormous amount of globally networked information. Typically, this information includes preexisting public library catalog data, digitized document collections, and other databases. In this article, we describe the distributed query system of a digital library prototype system known as HARP. In the HARP project, we have designed and implemented a distributed query processor and its query front-end to support integrated queries to preexisting public library catalogs and structured databases. This article describes our experiences in the design of an extended Sequel (SQL) query language known as HarpSQL. …

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Measurement Of W-Pair Production In E+E- Collisions At 183 Gev, R. Barate, Manoj Thulasidas Jan 1999

Measurement Of W-Pair Production In E+E- Collisions At 183 Gev, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The production of W+W− pairs is analysed in a data sample collected by ALEPH at a mean centre-of-mass energy of 182.7 GeV, corresponding to an integrated luminosity of 57 pb−1 . Cross sections are given for different topologies of W decays into leptons or hadrons. Under Standard Model assumptions for the W-pair production and decay, the W-pair cross section is measured to be 15.57 ± 0.62(stat.) ± 0.29(syst.) pb. Using also the W-pair data samples collected by ALEPH at lower centre-of-mass energies, the decay branching ratio of the W boson into hadrons is measured to be B(W → hadrons) = …

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Measurement Of The Hadronic Photon Structure Function At Lep 1 For 〈Q2〉 Values Between 9.9 And 284 Gev2, Barate, R.; Et Al., M. Thulasidas Jan 1999

Measurement Of The Hadronic Photon Structure Function At Lep 1 For 〈Q2〉 Values Between 9.9 And 284 Gev2, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Inclusive γ∗γ interactions to hadronic final states where one scattered electron or positron is detected in the electromagnetic calorimeters have been studied in the LEP 1 data taken by ALEPH from 1991 to 1995. The event sample has been used to measure the hadronic structure function of the photon F2γ in three bins with 〈Q2〉 of 9.9, 20.7 and 284 GeV2.

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Measurement Of The W Mass In E+E- Collisions At 183 Gev, Barate, R.; Et Al., M. Thulasidas Jan 1999

Measurement Of The W Mass In E+E- Collisions At 183 Gev, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

The mass of the W boson is obtained from reconstructed invariant mass distributions in W-pair events. The sample of W pairs is selected from 57 pb−1 collected with the ALEPH detector in 1997 at a centre-of-mass energy of 183 GeV.

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Search For The Standard Model Higgs Boson At The Lep2 Collider Near √S = 183 Gev, R. Barate, M. Thulasidas Jan 1999

Search For The Standard Model Higgs Boson At The Lep2 Collider Near √S = 183 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

During 1997 the ALEPH experiment at LEP gathered 57pb−1 of data at centre-of-mass energies near 183 GeV. These data are used to look for possible signals from the production of the Standard Model Higgs boson in the reaction e+e−→HZ. No evidence of a signal is found in the data; seven events are selected, in agreement with the expectation of 7.2 events from background processes. This observation results in an improved lower limit on the mass of the Higgs boson: mH>87.9GeV/c2 at 95% confidence level.

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Determination Of |Vub| From The Measurement Of The Inclusive Charmless Semileptonic Branching Ratio Of B Hadrons, R. Barate, M. Thulasidas Jan 1999

Determination Of |Vub| From The Measurement Of The Inclusive Charmless Semileptonic Branching Ratio Of B Hadrons, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

From a study of the kinematic properties of the final state produced in the semileptonic decays b→Xℓνℓb→Xℓνℓ, the inclusive charmless semileptonic branching ratio of b hadrons is measured. With a sample of 3.6 million hadronic Z decays recorded between 1992 and 1995 with the ALEPH detector at LEP, the value Br(b→Xuℓνℓ)Br(b→Xuℓνℓ) is determined to be (1.73±0.55stat±0.55syst)×10−3(1.73±0.55stat±0.55syst)×10−3, where XuXu represents any charmless hadronic state and b is a mixture of b hadrons weighted by their production rates. This measurement yields the result|Vub|2=(18.68±5.94stat±5.94syst±1.45HQE)×10−6,|Vub|2=(18.68±5.94stat±5.94syst±1.45HQE)×10−6,where the last error comes from the conversion of the branching ratio to the CKM matrix element squared.

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