Digital Commons Network^™

Systolic Algorithm For Processing Rle Images, Hao Feng, Fikret Erçal, Filiz Bunyak

Computer Science Faculty Research & Creative Works

Image difference operation is commonly used in on-line automated printed circuit board (PCB) inspection systems as well as many other image processing applications. In this paper, we describe a new systolic algorithm and its system architecture which computes image differences in run-length encoded (RLE) format. The efficiency of this operation greatly affects the overall performance of the inspection system. It is shown that, for images with a high similarity measure, the time complexity of the systolic algorithm is a small constant. A formal proof of correctness for the algorithm is also given in the paper.

Segmentation Of Printed Circuit Board Images Into Basic Patterns, Madhav Moganti, Fikret Ercal

Computer Science Faculty Research & Creative Works

Segmentation is the first and foremost step in the inspection of the printed circuit boards. In this paper a new technique for the segmentation of printed circuit board (PCB) images is presented. The technique basically segments a given PCB into small windows containing primitive PCB subpatterns. The technique proposed exploits the simplicity and the homogeneity of the PCB images and is inherently parallel. A detailed discussion of the experiments and the results obtained is also presented. © 1993 Academic Press.

An Interlibrary Loan System On The World Wide Web, Schubert Shou Boon Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

Inter-Library Loan (ILL) service is one of the services provided by libraries that offers users a way to access library resources beyond their affiliated libraries. Additionally, it allows participating libraries to share and maximize their resources. This work examines the ILL process used by libraries in Singapore and proposes that the existing paper-based manual system be replaced by a Web-based ILL system. Such a Web-based system has been successfully designed and implemented at the Nanyang Technological University. The paper presents an overview of the system requirements and architecture, implementation details and demonstrates the feasibility and advantages of the new system.

Java, Java, Java, Chaman Sabharwal

Computer Science Faculty Research & Creative Works

Everyone is talking about Java. The driving force for this chatter is Java''s simplicity and potential power. Java is programming language, and a language for the intranet and the World Wide Web (WWW). Java is a Write On one platform and Run on Many platforms (WORM) language. For network-friendly, platform-independent applications, Java (originally Oak) is an object oriented programming language. Java source code is compiled into a virtual machine code or bytecode. This makes the Java platform independent. It can be placed on a Web site, and executed on the client side on a PC-Intel, Mac, Motorola or UNIX-Solaris machine …

Creating A Canonical Scientific And Technical Information Classification System For Ncstrl+, Melissa E. Tiffany, Michael L. Nelson

Computer Science Faculty Publications

The purpose of this paper is to describe the new subject classification system for the NCSTRL+ project. NCSTRL+ is a canonical digital library (DL) based on the Networked Computer Science Technical Report Library (NCSTRL). The current NCSTRL+ classification system uses the NASA Scientific and Technical (STI) subject classifications, which has a bias towards the aerospace, aeronautics, and engineering disciplines. Examination of other scientific and technical information classification systems showed similar discipline-centric weaknesses. Traditional, library-oriented classification systems represented all disciplines, but were too generalized to serve the needs of a scientific and technically oriented digital library. Lack of a suitable existing …

Software Flexibility In A Web Environment, Michael Layng

Theses : Honours

Flexible software systems are designed to be able to adapt to changes in their environment without the need for programmer intervention. This allows companies and institutions to avoid the cost of hiring a programmer every time a business rule changes or a data structure is modified. The techniques of designing and implementing flexible 3GL software systems have been proven as a means of reducing the high cost of software maintenance caused by the changing of systems requirements. Such systems have been in operation in the European finance sector since the early 1980's. Edith Cowan University is participating in current research …

Measurement Of The Axial-Vector Τ Spectral Functions And Determination Of Αs (M2Τ) From Hadronic Τ Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

An analysis based on 124 000 selected ττ pairs recorded by the ALEPH detector at LEP provides the vector (V)(V) and axial-vector (A)(A) spectral functions of hadronic ττ decays together with their total widths. This allows the evaluation of finite energy chiral sum rules that are weighted integrals over the (V−A)(V−A) spectral functions. In addition, a precise measurement of αsαs along with a determination of nonperturbative contributions at the ττ mass scale is performed. The experimentally and theoretically most robust determination of αs(M2τ)αs(Mτ2) is obtained from the (V+A)(V+A) fit that yields αs(M2τ)=0.334±0.022αs(Mτ2)=0.334±0.022 giving αs(M2Z)=0.1202±0.0027αs(MZ2)=0.1202±0.0027 after the extrapolation to the mass …

Search For Supersymmetry With A Dominant R-Parity Violating Llē Coupling In E+E- Collisions At Centre-Of-Mass Energies Of 130 Gev To 172 Gev, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LLE¯LLE¯ coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130–172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This is translated into lower limits on the mass of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, charginos with masses less than 73 GeV/c2c2 and neutralinos with masses less than 23 GeV/c2c2 are excluded at 95% confidence level for any generation structure of the LLE¯LLE¯ coupling, and for neutralino, slepton …

Study Of B0s Oscillations And Lifetime Using Fully Reconstructed D̄S Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A search for B0sBs0 oscillations is performed using approximately 4 million Z→qq¯Z→qq¯ events collected by the ALEPH experiment during 1991–1995. B0sBs0 candidates are partially reconstructed by combining tracks with fully reconstructed D−sDs− candidates. The B0sBs0 production flavour is estimated from the sign of the opposite hemisphere charge, a fragmentation kaon in the same hemisphere, or a lepton in the opposite hemisphere. From a total sample of 1620 candidates, with a B0sBs0 purity estimated to be 22%, all values of ΔmsΔms below 3.9 ps−1−1 and between 6.5 and 8.8 ps−1−1 are excluded at 95% CL. From the same sample, the B0sBs0 …

An Integrated Web-Based Ill System For Singapore Libraries, Schubert Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The paper proposes an integrated Web-based inter-library loan (ILL) system to replace and enhance the existing manual-based ILL system used by Singapore libraries. It describes the system requirements that must be supported in order to make it a viable and acceptable solution to all participating libraries. Subsequently, it presents the client-server Web-based system architecture, database design and Java development platform that are used to implement the system. The new system exhibits a host of advantages over the manual system including the minimising of human resource by eliminating form-filling and other forms of paper work completely, improving the access and speed …

Specification-Driven Optimization, Sheena Day

Dissertations and Theses

Traditionally, optimizing transformations have been built into compilers. The end-user has little or no control over guiding any optimizations that may be applied by the compiler. Moreover, the compiler-writer does not have a simple way to direct the optimizations. Thus, many potentially beneficial opportunities for code optimization may be lost. We have built a system that allows the user to participate in guiding source-to-source transformations via the specification of rewrite rules. A clean separation of the rules from the strategy of applying them makes the system easier to use and modify, compared to other integrated systems. This is especially relevant …

Learning To See Analogies: A Connectionist Exploration, Douglas S. Blank

Computer Science Faculty Research and Scholarship

The goal of this dissertation is to integrate learning and analogy-making. Although learning and analogy-making both have long histories as active areas of research in cognitive science, not enough attention has been given to the ways in which they may interact. To that end, this project focuses on developing a computer program, called Analogator, that learns to make analogies by seeing examples of many different analogy problems and their solutions. That is, it learns to make analogies by analogy. This approach stands in contrast to most existing computational models of analogy in which particular analogical mechanisms are assumed a priori …

Bias And The Probability Of Generalization, Tony R. Martinez, D. Randall Wilson

Faculty Publications

In order to be useful, a learning algorithm must be able to generalize well when faced with inputs not previously presented to the system. A bias is necessary for any generalization, and as shown by several researchers in recent years, no bias can lead to strictly better generalization than any other when summed over all possible functions or applications. This paper provides examples to illustrate this fact, but also explains how a bias or learning algorithm can be “better” than another in practice when the probability of the occurrence of functions is taken into account. It shows how domain knowledge …

Ta Da! - The Text Adventure Design Assistant A Visual Tool For The Development Of Adventure Games, Sean Molley

Masters Theses & Specialist Projects

In this paper, I survey past and present tools available to text adventure game authors, and then describe a new product: the Text Adventure Design Assistant (TA DA!), a visual programming system for creating text adventure games. My system consists of two parts: an abstract framework which defines an archetypical game, and a user interface which allows for the construction of games in a visual manner by manipulating the elements of the abstract game to produce a concrete design. The two most popular contemporary programming languages for creating text adventure games, TADS and Inform, are compared and contrasted, and my …

Inclusive Production Of Neutral Pions In Hadronic Z Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the inclusive production of π0 mesons in hadronic Z decays is presented and compared to Monte Carlo model predictions. The analysis is based on approximately 2 million hadronic events recorded with the ALEPH detector at LEP at a centre-of-mass energy of ⊡s = 91.2 GeV. Neutral pions are reconstructed using photons measured in the electromagnetic calorimeter and photons from conversion pairs. The inclusive π0 momentum spectrum is measured in the range 0.025 x p = p/p beam 0 per hadronic Z is found to be 4.80 ± 0.07(stat) ± 0.31(sys). The differential inclusive π0 cross section is …

The Effect Of Data Model, System And Task Characteristics On User Query Performance – An Empirical Study, Hock Chan, Keng Siau, Kwok-Kee Wei

Research Collection School Of Computing and Information Systems

With the proliferation of end-user computing and empowerment of end users in the organizations, the user-database interface is increasingly being recognized as an important research area. A user-database interface consists of two key components: the data model and the query language. Database management system designers can manipulate these two components to produce an effective database interface to maximize user task performance. However, in order to do this, the designers first need to know the effect of the two components on end users and the interaction effect of the two components. Despite the acknowledgment of user-database interface as a cornerstone in …

Developing A Corpus Specific Stoplist Using Quantitative Comparison, Craig N. Berg

Theses and Dissertations

We have become overwhelmed with electronic information and it seems our situation is not going to improve. It is becoming increasingly common for people to work with information on a daily basis. We seem to spend more and more time looking for information, and it is taking longer because more information is available. This thesis will look at how we can provide faster access to the information we want to find. Today's requirements are closely related to searching for information using queries. At the heart of the query process is the removal of search terms having little or no significance …

Market-Based Resource Control For Mobile Agents, Jonathan Bredin, David Kotz, Daniela Rus

Computer Science Technical Reports

Mobile agents are programs that can migrate from machine to machine in a heterogeneous, partially disconnected network. As mobile agents move across a network, they consume resources. We discuss a system for controlling the activities of mobile agents that uses electronic cash, a banking system, and a set of resource managers. We describe protocols for transactions between agents. We present fixed-pricing and dynamic-pricing policies for resources. We focus on and analyze the sealed-bid second-price auction as a mechanism for dynamic pricing.

Simulation Study Of Learning Automata Games In Automated Highway Systems, Cem Unsal, Pushkin Kachroo, John S. Bay

Electrical & Computer Engineering Faculty Research

One of the most important issues in Automated Highway System (AHS) deployment is intelligent vehicle control. While the technology to safely maneuver vehicles exists, the problem of making intelligent decisions to improve a single vehicle’s travel time and safety while optimizing the overall traffic flow is still a stumbling block. We propose an artificial intelligence technique called stochastic learning automata to design an intelligent vehicle path controller. Using the information obtained by on-board sensors and local communication modules, two automata are capable of learning the best possible (lateral and longitudinal) actions to avoid collisions. This learning method is capable of …

Tertiary Storage In Multimedia Systems: Staging Or Direct Access?, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

Multimedia applications that are required to manipulate large collections of objects are becoming increasingly common. Moreover, the size of multimedia objects, which are already huge, are getting even bigger as the resolution of output devices improve. As a result, many multimedia storage systems are not likely to be able to keep all of their objects disk-resident. Instead, a majority of the less popular objects have to be off-loaded to tertiary storage to keep costs down. The speed at which objects can be accessed from tertiary storage is thus an important consideration. In this paper, we propose an adaptive data retrieval …

Searches For Scalar Top And Scalar Bottom Quarks At Lep2, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Searches for scalar top and bottom quarks have been performed with data collected by the ALEPH detector at LEP. The data sample consists of 21.7 pb−1 taken at √ s = 161, 170, and 172 GeV and 5.7 pb−1 taken at √ s = 130 and 136 GeV. No evidence for scalar top quarks or scalar bottom quarks was found in the channels ˜t → cχ, ˜t → bℓν˜, and b˜ → bχ. For the channel ˜t → cχ a limit of 67 GeV/c 2 has been set on the scalar top quark mass, independent of the mixing angle between …

Updated Measurement Of The Τ Lepton Lifetime, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

A new measurement of the mean lifetime of the τ lepton is presented. Three different analysis methods are applied to a sample of 90000 τ pairs, collected in 1993 and 1994 with the ALEPH detector at LEP. The average of this measurement and those previously published by ALEPH is ττ = 290.1±1.5±1.1fs.

Materialized View Algorithms, Yubo Fan

Dissertations and Theses

A data warehouse is a stand-alone repository of integrated information available for decision support OLAP querying and analysis. Aggregate views can be materialized (stored in disk) to improve query performance in a data warehouse.

Several static and dynamic algorithms for selecting materialized aggregate views (MAV) in a data warehouse are proposed in this thesis. The algorithms are then compared by running a simulation system, which can be configured to compare several algorithms on different type of data warehouses. Simulation results for static algorithms are presented to show that several proposed algorithms perform close to an existing good algorithm (HRU Greedy) …

Search For The Standard Model Higgs Boson In E+E- Collisions At √S = 161, 170 And 172 Gev, Barate, R.; 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. The data sample consists of integrated luminosities of 10:9 pb1 , 1:1 pb1 , and 9:5 pb1 collected by the ALEPH experiment at LEP during 1996, at centre-of-mass energies of 161, 170 and 172 GeV, respectively. No candidate events were found, in agreement with the expected background of 0.84 events from all Standard Model processes. This search results in a 95% C.L. lower limit on the Higgs boson mass of 69:4 GeV=c2 . When combined with earlier ALEPH searches performed at energies at and …

Data Mining, Yongjian Fu

Computer Science Faculty Research & Creative Works

Data mining is the process of identifying interesting patterns from large databases. It is the core part of the knowledge discovery in database (KDD) process. Tasks in data mining are classified into summarization, classification, clustering, association and trend analysis. Data mining techniques are adopted from many research areas including statistics, machine learning, database systems, neural networks, rough sets and visualization. The techniques have been applied successfully in many areas from business to science to sports.

Formal Specification Of Fragmentation And Reassembly In Ipv6, Ibrahim Sahin

Electrical & Computer Engineering Theses & Dissertations

Development and implementation of a networking standard such as the new Internet Protocol (IPv6) is a very difficult process. Different implementations of the standard must be fully compatible to allow different computers to communicate with each other. However, standards are often ambiguous, frequently a result of providing specifications in the English language. A more formal specification could assist in the design of systems. This thesis demonstrates that capability using the Prototype Verification System (PVS).

In this thesis study, a formal specification for fragmentation and reassembly in IPv6 was created to provide a tool for the standardization of IPv6 using PVS. …

Search For Sleptons In E+E- Collisions At Centre-Of-Mass Energies Of 161 Gev And 172 Gev, R. Barate, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

The data recorded by the ALEPH experiment at LEP at centre–of–mass energies of 161 GeV and 172 GeV were analysed to search for sleptons, the supersymmetric partners of leptons. No evidence for the production of these particles was found. The number of candidates observed is consistent with the background expected from four–fermion processes and γγ–interactions. Improved mass limits at 95% C.L. are reported.

Information Retrieval On The World Wide Web, Venkat N. Gudivada, Vijay V. Raghavan, William I. Grosky, Rajesh Kasanagottu

Computer Science Faculty Research & Creative Works

Effective search and retrieval are enabling technologies for realizing the full potential of the Web. The authors examine relevant issues, including methods for representing document content. They also compare available search tools and suggest methods for improving retrieval effectiveness.

A Measurement Of The Qcd Colour Factors And A Limit On The Light Gluino, Barate, R.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

Using data collected from 1992 to 1995 with the ALEPH detector at LEP, a measurement of the colour factor ratios CA/CF and TF /CF and the strong coupling constant αs = CFαs(MZ)/(2π) has been performed by fitting theoretical predictions simultaneously to the measured differential two-jet rate and angular distributions in four-jet events. The result is found to be in excellent agreement with QCD, {fx4-1} Fixing CA/CF and TF/CF to the QCD values permits a determination of αs(MZ) and ηf, the number of active flavours. With this measurement the existence of a gluino with mass below 6.3 GeV/c2 is excluded at …

Multiple Representation For Understanding Data Structures, Biffah Hancies, Venky Shankararaman, Jose Munoz

Research Collection School Of Computing and Information Systems

In this paper an approach to enhance the learning of abstract computing concepts by novice students is presented. This approach is based on effective use of multiple visual representations, and it was applied within the domain of linear data structures: array, stack, queue and linked list. A prototype computer-based instructional system called MRUDS (Multiple Representation for Understanding Data Structures) was developed and evaluated. It was found from the evaluation that the three presentation modules namely, analogy, representation and algorithm contributed to the students' learning process, each contributing to and reinforcing the effect of the others.