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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 …


Putting Type Annotations To Work, Martin Odersky, Konstantin Laufer Jan 1996

Putting Type Annotations To Work, Martin Odersky, Konstantin Laufer

Computer Science: Faculty Publications and Other Works

We study an extension of the Hindley/Milner system with explicit type scheme annotations and type declarations. The system can express polymorphic function arguments, user-defined data types with abstract components, and structure types with polymorphic fields. More generally, all programs of the polymorphic lambda calculus can be encoded by a translation between typing derivations. We show that type reconstruction in this system can be reduced to the decidable problem of first-order unification under a mixed prefix.


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 …


Improved Data Migration And Processing For Projecting The Financial Aid Budget, Jeffery L. Olson '96 Jan 1996

Improved Data Migration And Processing For Projecting The Financial Aid Budget, Jeffery L. Olson '96

Honors Projects

Last fall, I again resumed work on the budget projection model that encompassed five spreadsheets. Four of these sheets generated a set of statistical averages for each class. Each one consisted of 101 columns containing data for the four-to five-hundred students(rows) in each class. In addition, a fifth sheet used these averages to generate a highly accurate prediction for expenditures in the upcoming year. However, there were two main areas of improvement that became readily apparent: importing data and the sheets themselves.


Automatic Pcb Inspection Algorithms: A Survey, Madhav Moganti, Fikret Ercal, Cihan H. Dagli, Shou Tsunekawa Jan 1996

Automatic Pcb Inspection Algorithms: A Survey, Madhav Moganti, Fikret Ercal, Cihan H. Dagli, Shou Tsunekawa

Computer Science Faculty Research & Creative Works

The importance of the inspection process has been magnified by the requirements of the modern manufacturing environment. In electronics mass-production manufacturing facilities, an attempt is often made to achieve 100% quality assurance of all parts, subassemblies, and finished goods. A variety of approaches for automated visual inspection of printed circuits have been reported over the past two decades. In this survey, algorithms and techniques for the automated inspection of printed circuit boards are examined. A classification tree for these algorithms is presented and the algorithms are grouped according to this classification. This survey concentrates mainly on image analysis and fault …


A Systematic Tradeoff Methodology For Acquiring And Validating Imprecise Requirements, J. Yen, Xiaoqing Frank Liu, W. A. Tiao Jan 1996

A Systematic Tradeoff Methodology For Acquiring And Validating Imprecise Requirements, J. Yen, Xiaoqing Frank Liu, W. A. Tiao

Computer Science Faculty Research & Creative Works

Requirement analysis is one of the most important phases in a software development process. Existing requirement methodologies are limited in specifying requirements that are usually vague and imprecise, and in supporting tradeoff analysis between the conflicting requirements. In this paper, the elasticity of imprecise requirements is captured using fuzzy logic to facilitate tradeoffs between conflicting requirements. Based on the marginal rate of substitution in decision science, we have developed a systematic approach to elicit the structures and the parameters of imprecise requirements, to validate the scheme for aggregating requirements, and to assess relative priorities of conflicting requirements.


Adaptive Information Filtering As A Means To Overcome Information Overload, Daniel R. Tauritz Jan 1996

Adaptive Information Filtering As A Means To Overcome Information Overload, Daniel R. Tauritz

Computer Science Faculty Research & Creative Works

Information Filtering is concerned with filtering data streams in such a way as to leave only pertinent data (information) to be perused. When the data streams are produced in a changing environment (as most if not all are) the filtering has to adapt too in order to remain effective. Adaptive Information Filtering (AIF) is concerned with filtering 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 interest of a user can change). The thesis research described in this paper combines trigram analysis, clustering, and …


Concepts Of Adaptive Information Filtering, Daniel R. Tauritz Jan 1996

Concepts Of Adaptive Information Filtering, Daniel R. Tauritz

Computer Science Faculty Research & Creative Works

This paper was written for the project study “Adaptive Information Filtering” at the Department of Computer Science, Leiden University, The Netherlands. The assignment was to write an introduction to Adaptive Information Filtering (AIF), based on the author’s ideas for his M.Sc. thesis, and with as large an audience as possible in mind. In addition to a simple introduction to AIF, this paper should also provide easy introductions to clustering algorithms, evolutionary computation, and n-gram analysis. (Preface, page 2)


Optimization Of The Discriminatory Power Of A Trigram Based Document Clustering Algorithm Using Evolutionary Computation, Daniel R. Tauritz Jan 1996

Optimization Of The Discriminatory Power Of A Trigram Based Document Clustering Algorithm Using Evolutionary Computation, Daniel R. Tauritz

Computer Science Faculty Research & Creative Works

No abstract provided.


A Family Of Parallel Runge-Kutta Pairs, P. Bogacki Jan 1996

A Family Of Parallel Runge-Kutta Pairs, P. Bogacki

Mathematics & Statistics Faculty Publications

Increasing availability of parallel computers has recently spurred a substantial amount of research concerned with designing explicit Runge-Kutta methods to be implemented on such computers. Here, we discuss a family of methods that require fewer processors than methods presently available do, still achieving a similar speed-up. In particular, (5,6) and (6,7) pairs are derived, that require a minimum number of function evaluations on two and three processors, respectively.


Simulator For The Performance Analysis Of Cpm Schemes In An Indoor Wireless Environment, Ronald Chua Jan 1996

Simulator For The Performance Analysis Of Cpm Schemes In An Indoor Wireless Environment, Ronald Chua

Theses : Honours

A software simulator for characterising Continuous Phase Modulation (CPM) schemes in an indoor multipath environment has been developed using SIMULINK and MATLAB. The simulator is capable of simulating a wide range of CPM schemes to determine bandwidth efficiency and robustness to additive white Gaussian noise (AWGN) and Rician fading. Initial trials of the simulator indicate that the simulator is functioning correctly. Eventually, the simulator will be used to determine the most suitable modulation scheme for the development of an actual indoor wireless system.


Time- And Cost-Optimal Parallel Algorithms For The Dominance And Visibility Graphs, D. Bhagavathi, H. Gurla, S. Olariu, J. L. Schwing, J. Zhang Jan 1996

Time- And Cost-Optimal Parallel Algorithms For The Dominance And Visibility Graphs, D. Bhagavathi, H. Gurla, S. Olariu, J. L. Schwing, J. Zhang

Computer Science Faculty Publications

The compaction step of integrated circuit design motivates associating several kinds of graphs with a collection of non-overlapping rectangles in the plane. These graphs are intended to capture various visibility relations amongst the rectangles in the collection. The contribution of this paper is to propose time- and cost-optimal algorithms to construct two such graphs, namely, the dominance graph (DG, for short) and the visibility graph (VG, for short). Specifically, we show that with a collection of n non-overlapping rectangles as input, both these structures can be constructed in θ (log n) time using n processors in the CREW model.


Arbitrary Views Of High-Dimensional Space And Data, Andrew Ellerton Jan 1996

Arbitrary Views Of High-Dimensional Space And Data, Andrew Ellerton

Theses : Honours

Computer generated images of three dimensional scenes objects are the result of parallel/perspective projections of the objects onto a two dimensional plane. The computational techniques may be extended to project n-dimensional hyperobjects onto (n-1) dimensions, for n > 3. Projection to one less dimension may be applied recursively for data of any high dimension until that data is two-dimensional, when it may be directed to a computer screen or to some other two-dimensional output device. Arbitrary specification of eye location, target location, field-of-view angles and other parameters provide flexibility, so that data may be viewed-and hence perceived-in previously unavailable ways. However, …


The Design And Implementation Of A Toolkit For The Creation Of Virtual Environments, Jesse Kinross-Smith Jan 1996

The Design And Implementation Of A Toolkit For The Creation Of Virtual Environments, Jesse Kinross-Smith

Theses : Honours

Virtual Reality is a field that is steadily increasing in popularity and interest. New developments in both hardware and software have empowered developers with new devices allowing faster and better quality interaction with virtual environments. However, the emphasis of research in virtual environments has been more concerned with development of new display and input devices, as opposed to the investigation of different methods of interaction that a three-dimensional environment offers. This project designs and implements a three-dimensional, interactive, virtual environment development system upon an existing three-dimensional rendering engine. The aim of the project is to allow users to generate virtual …


Combinatorial Approaches For Hard Problems In Manpower Scheduling, Hoong Chuin Lau Jan 1996

Combinatorial Approaches For Hard Problems In Manpower Scheduling, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Manpower scheduling is concerned with the construction of a workers' schedule which meets demands while satisfying given constraints. We consider a manpower scheduling Problem, called the Change Shift Assignment Problem(CSAP). In previous work, we proved that CSAP is NP-hard and presented greedy methods to solve some restricted versions. In this paper, we present combinatorial algorithms to solve more general and realistic versions of CSAP which are unlikely solvable by greedy methods. First, we model CSAP as a fixed-charge network and show that a feasible schedule can be obtained by finding disjoint paths in the network, which can be derived from …


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.).


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 …


A Policy-Independent Secure X Server, Kirk Joseph Bittler Jan 1996

A Policy-Independent Secure X Server, Kirk Joseph Bittler

Dissertations and Theses

This thesis demonstrates that a secure X system can be designed and implemented to be independent of a particular security policy. The advantages and costs of a separation of security policy and enforcement are examined by developing a large scale application, the DX windowing system, on a DTOS platform. DTOS is a high assurance operating system that isolates policy decisions in a Security Server. A security conscious process, such as DX, eliminates policy considerations from the code. The process instead consults the Security Server and enforces the decisions that server derives from the policy. The DX architecture is described and …


Embedded Particle Computation In Evolved Cellular Automata, Wim Hordijk, James P. Crutchfield, Melanie Mitchell Jan 1996

Embedded Particle Computation In Evolved Cellular Automata, Wim Hordijk, James P. Crutchfield, Melanie Mitchell

Computer Science Faculty Publications and Presentations

In our work we are studying how genetic algorithms (GAs) can evolve cellular automata (CAs) to perform computations that require global coordination. The evolving cellular automata" framework is an idealized means for studying how evolution (natural or computational) can create systems that perform emergent computation, in which the actions of simple components with local information and communication give rise to coordinated global information processing [3].

In previous work [4, 5], we analyzed the process by which a genetic algorithm designed CAs to perform particular tasks. In this paper we focus on how these CAs implement the emergent computational strategies for …


Parallel Newton-Krylov-Schwarz Solvers For The Full Potential Flow Equation, Jie Zhang Jan 1996

Parallel Newton-Krylov-Schwarz Solvers For The Full Potential Flow Equation, Jie Zhang

Computer Science Theses & Dissertations

Newton-Krylov-Schwarz methods are increasingly applied in Computational Fluid Dynamics (CFD). We develop a parallel analysis code based on this method for the full potential flow model. The full potential model consists of a single nonlinear second-order partial differential equation of mixed type (elliptic/hyperbolic), which we solve as a steady boundary-value problem.

We use a nine-point finite-difference stencil to discretize the equation. A Newtonlike linearization and correction method is used to solve the resulting set of nonlinear algebraic equations. To solve the inner linear equations, we employ a Krylov space method. Preconditioners are used to improve the convergence rate. In order …


A Search Tool To Enhance The Selection And Utilisation Of Reusable Software Modules Within The Object-Oriented Paradigm, Robert H. Cross Jan 1996

A Search Tool To Enhance The Selection And Utilisation Of Reusable Software Modules Within The Object-Oriented Paradigm, Robert H. Cross

Theses: Doctorates and Masters

The affinity for reuse within the object-oriented paradigm may enable high levels of productivity; however, gains will become realisable only if a systems developer has access to tools which aid in the selection of classes. A method for object-oriented analysis and design is detailed and its process is assisted by an object-oriented search tool based on reference and corporate library technology. The search tool contributes to the determination of suitable existing inheritable classes and an explanation of its construction and use is included. A practical demonstration of the method, using the search tool, is elaborated. The thesis demonstrates that text …


Designing Dependencies, Howard A. Blair Dec 1995

Designing Dependencies, Howard A. Blair

Electrical Engineering and Computer Science - Technical Reports

Given a binary recursively enumerable relation R, one or more logic programs over a language L can be constructed and interconnected to produce a dependency relation D on selected predicates within the Herbrand base BL of L isomorphic to R. D can be, optionally, a positive, negative or mixed dependency relation. The construction is applied to representing any effective game of the type introduced by Gurevich and Harrington, which they used to prove Rabin's decision method for S2S, as the dependency relation of a logic program. We allow games over an infinite alphabet of possible moves. We use this representation …


The Application Of Hybridized Genetic Algorithms To The Protein Folding Problem, Robert L. Gaulke Dec 1995

The Application Of Hybridized Genetic Algorithms To The Protein Folding Problem, Robert L. Gaulke

Theses and Dissertations

The protein folding problem consists of attempting to determine the native conformation of a protein given its primary structure. This study examines various methods of hybridizing a genetic algorithm implementation in order to minimize an energy function and predict the conformation (structure) of Met-enkephalin. Genetic Algorithms are semi-optimal algorithms designed to explore and exploit a search space. The genetic algorithm uses selection, recombination, and mutation operators on populations of strings which represent possible solutions to the given problem. One step in solving the protein folding problem is the design of efficient energy minimization techniques. A conjugate gradient minimization technique is …


Dynamics Of Binary Liquids In Pores, J.C. Lee Dec 1995

Dynamics Of Binary Liquids In Pores, J.C. Lee

Faculty Publications

A computer simulation is performed to study the dynamics of binary liquids in the pores of Vycor glasses. The pores are modeled with glass walls that form randomly interconnected tunnels. When the relaxation is probed with a particular wavelength, the time autocorrelation function depends on whether or not there is a significant periodic or quasiperiodic structure in the distribution of the walls with that wavelength. If there is not, the relaxation may be fitted as the sum of an exponential term and a nonexponential activated term. If there is, the relaxation shows a long-lasting tail that can be fitted by …


Semantic Interpretation Of An Artificial Neural Network, Stanley D. Kinderknecht Dec 1995

Semantic Interpretation Of An Artificial Neural Network, Stanley D. Kinderknecht

Theses and Dissertations

Recent advances in machine learning theory have opened the door for applications to many difficult problem domains. One area that has achieved great success for stock market analysis/prediction is artificial neural networks. However, knowledge embedded in the neural network is not easily translated into symbolic form. Recent research, exploring the viability of merging artificial neural networks with traditional rule-based expert systems, has achieved limited success. In particular, extracting production (IF.. THEN) rules from a trained neural net based on connection weights provides a valid set of rules only when neuron outputs are close to 0 or 1 (e.g. the output …


Deriving Optimal Solutions From Incomplete Knowledge Bases, Shawn A. Northrop Dec 1995

Deriving Optimal Solutions From Incomplete Knowledge Bases, Shawn A. Northrop

Theses and Dissertations

Many real world domains cannot be represented using Bayesian Networks due to the need for complete probability tables and acyclic knowledge. However, Bayesian Knowledge Bases (BKBs) are a viable method for representing these incomplete domains, but very little research has been performed on inferencing with them. This paper presents three inference engines for extracting optimal solutions from three distinct BKB subclasses: singly- connected, multiply-connected with mutually exclusive cycles, and cyclic. The singly-connected inference engine has a worst case polynomial run time. Performance improvement techniques for increasing inference engine speed are discussed, in addition to a new tool for measuring incompleteness …


Neural Network Analysis Of Chemical Compounds In Nonrebreathing Fisher-344 Rat Breath, Robert E. Sackett Jr. Dec 1995

Neural Network Analysis Of Chemical Compounds In Nonrebreathing Fisher-344 Rat Breath, Robert E. Sackett Jr.

Theses and Dissertations

This research applies statistical and artificial neural network analysis to data obtained from measurement of organic compounds in the breath of a Fisher-344 rat. The Research Triangle Institute (RTI) developed a breath collection system for use with rats in order to collect and determine volatile organic compounds (VOCs) exhaled. The RTI study tested the hypothesis that VOCs, including endogenous compounds, in breath can serve as markers to exposure to various chemical compounds such as drugs, pesticides, or carcinogens normally foreign to living organisms. From a comparative analysis of chromatograms, it was concluded that the administration of carbon tetrachloride dramatically altered …


Dynamic Transfer Of Control Between Manned And Unmanned Simulation Actors, Neal W. Schneider Dec 1995

Dynamic Transfer Of Control Between Manned And Unmanned Simulation Actors, Neal W. Schneider

Theses and Dissertations

This thesis continues the ongoing research at the Air Force Institute of Technology's Virtual Environments Laboratory in the area of distributed simulation. As the relevance and interest of interactive simulation as a training medium continues to grow, there is a pressing need to provide more realistic and numerous intelligent autonomous agents for simulations. As those autonomous agents mature and become more realistic, the need exists to be able to handle individual agents by taking control of them and operating them as manned agents at certain points within the simulation. The author started with a protocol proposed in a working draft …


Kenematic Tolerance Analysis, Leo Joskowicz, Elisha Sacks, Vijay Srinivasan Dec 1995

Kenematic Tolerance Analysis, Leo Joskowicz, Elisha Sacks, Vijay Srinivasan

Department of Computer Science Technical Reports

No abstract provided.