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Full-Text Articles in Science and Technology Studies

Characterizations Of Classes Of Programs By Three-Valued Operators, Anthony K. Seda, Pascal Hitzler Dec 1999

Characterizations Of Classes Of Programs By Three-Valued Operators, Anthony K. Seda, Pascal Hitzler

Computer Science and Engineering Faculty Publications

Several important classes of normal logic programs, including the classes of acyclic, acceptable, and locally hierarchical programs, have the property that every program in the class has a unique two-valued supported model. In this paper, we call such classes unique supported model classes. We analyse and characterize these classes by means of operators on three-valued logics. Our studies will motivate the definition of a larger unique supported model class which we call the class of Phi-accessible programs. Finally, we show that the class of Phi -accessible programs is computationally adequate in that every partial recursive function can be implemented by …


On-Line Bayesian Tree-Structured Transformation Of Hidden Markov Models For Speaker Adaptation, Shaojun Wang, Yunxin Zhao Dec 1999

On-Line Bayesian Tree-Structured Transformation Of Hidden Markov Models For Speaker Adaptation, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents a new recursive Bayesian learning approach for transformation parameter estimation in speaker adaptation. Our goal is to incrementally transform (or adapt) the entire set of HMM parameters for a new speaker or new acoustic enviroment from a small amount of adaptation data. By establishing a clustering tree of HMM Gaussian mixture components, the finest affine transformation parameters for individual HMM Gaussian mixture components can be dynamically searched. The on-line Bayesian learning technique proposed in our recent work is used for recursive maximum a posteriori estimation of affine transformation parameters. Speaker adaptation experiments using a 26-letter English alphabet …


Efficient Support For Decision Flows In E-Commerce Applications, Richard Hull, Francois Llirbat, Jianwen Su, Guozhu Dong, Bharat Kumar, Gang Zhou Oct 1999

Efficient Support For Decision Flows In E-Commerce Applications, Richard Hull, Francois Llirbat, Jianwen Su, Guozhu Dong, Bharat Kumar, Gang Zhou

Kno.e.sis Publications

In the coming era of segment-of-one marketing, decisions about business transactions will be quite intricate, so that customer treatments can be highly individualized, reflecting customer preferences, targeted business objectives, etc. This paper describes a paradigm called “decision flows” for specifying a form of incremental decision-making that can combine a myriad of diverse business factors and be executed in near-realtime. Starting with initial input, a decision flow will iteratively gather and derive additional information until a conclusion is reached. Decision flows can be specified in a rules-based manner that generalizes so-called “business rules” but provides more structure than traditional expert systems. …


Critical It Role In Healthcare: National Agenda, Applications, And Technologies, Jack Corley, Warren Karp, Amit P. Sheth Oct 1999

Critical It Role In Healthcare: National Agenda, Applications, And Technologies, Jack Corley, Warren Karp, Amit P. Sheth

Kno.e.sis Publications

We share a widely-held vision that tomorrow's health care will be delivered by a distributed team using a knowledge based process that is focused on prevention and wellness. Caregivers will be able to treat and monitor patients where and when needed, capturing data as a natural byproduct of care delivery. Clinical teams with a wide range of skills and expertise will deliver consistent, quality care based on timely, situation-specific knowledge and guidance derived from outcomes evidence. That same knowledge will support advances in healthcare research and education. Home care and remote medicine will increase, reducing the need for high-cost hospitalization. …


A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller Jun 1999

A Multilevel Secure Workflow Management System, Myong H. Kang, Judith N. Froscher, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller

Kno.e.sis Publications

The Department of Defense (DoD) needs multilevel secure (MLS) workflow management systems to enable globally distributed users and applications to cooperate across classification levels to achieve mission critical goals. An MLS workflow management system that allows a user to program multilevel mission logic, to securely coordinate widely distributed tasks, and to monitor the progress of the workflow across classification levels is required. In this paper, we present a roadmap for implementing MLS workflows and focus on a workflow builder that is a graphical design tool for specifying such workflows.


Addressing The Inadequacies Of Information Available On The Internet: The Prospect For A Technical Solution, Alan I. Goldman Jun 1999

Addressing The Inadequacies Of Information Available On The Internet: The Prospect For A Technical Solution, Alan I. Goldman

Critical and Creative Thinking Capstones Collection

In the past ten years the Internet has been the carrier and transmitter of vast amounts of information. Most of it has never been subjected to peer review or even casual review and has therefore been the source of misinformation. Additionally, there is need for more researchers to utilize critical thinking techniques of evaluating the credibility of sources.

This paper chronicles my critical and creative thinking processes and results regarding these three areas of the information problems that are prevalent on the Internet. The first area is the problem of bad, biased or incorrect information including hoaxes and scams. I …


How Proteins Fold, Flex, And Bind Other Molecules, Leslie A. Kuhn, Volker Schnecke, Michael L. Raymer, Paul C. Sanschagrin Apr 1999

How Proteins Fold, Flex, And Bind Other Molecules, Leslie A. Kuhn, Volker Schnecke, Michael L. Raymer, Paul C. Sanschagrin

Kno.e.sis Publications

No abstract provided.


Data Integration By Describing Sources With Constraint Databases, Xun Cheng, Guozhu Dong, Tzekwan Lau, Jianwen Su Mar 1999

Data Integration By Describing Sources With Constraint Databases, Xun Cheng, Guozhu Dong, Tzekwan Lau, Jianwen Su

Kno.e.sis Publications

We develop a data integration approach for the efficient evaluation of queries over autonomous source databases. The approach is based on some novel applications and extensions of constraint database techniques. We assume the existence of a global database schema. The contents of each data source are described using a set of constraint tuples over the global schema; each such tuple indicates possible contributions from the source. The “source description catalog” (SDC) of a global relation consists of its associated constraint tuples. Such a method of description is advantageous since it is flexible to add new sources and to modify existing …


Efficient Mining Of Partial Periodic Patterns In Time Series Database, Jiawei Han, Guozhu Dong, Yiwen Yin Mar 1999

Efficient Mining Of Partial Periodic Patterns In Time Series Database, Jiawei Han, Guozhu Dong, Yiwen Yin

Kno.e.sis Publications

Partial periodicity search, i.e., search for partial periodic patterns in time-series databases, is an interesting data mining problem. Previous studies on periodicity search mainly consider finding full periodic patterns, where every point in time contributes (precisely or approximately) to the periodicity. However, partial periodicity is very common in practice since it is more likely that only some of the time episodes may exhibit periodic patterns.

We present several algorithms for efficient mining of partial periodic patterns, by exploring some interesting properties related to partial periodicity, such as the Apriori property and the max-subpattern hit set property, and by shared mining …


Multivalued Mappings, Fixed-Point Theorems And Disjunctive Databases, Pascal Hitzler, Anthony K. Seda Jan 1999

Multivalued Mappings, Fixed-Point Theorems And Disjunctive Databases, Pascal Hitzler, Anthony K. Seda

Computer Science and Engineering Faculty Publications

In this paper, we discuss the semantics of disjunctive programs and databases and show how multivalued mappings and their fixed points arise naturally within this context. A number of fixed-point theorems for multivalued mappings are considered, some of which are already known and some of which are new. The notion of a normal derivative of a disjunctive program is introduced. Normal derivatives are normal logic programs which are determined by the disjunctive program. Thus, the well-known single-step operator associated with a normal derivative is single-valued, and its fixed points can be found by well-established means. It is shown how fixed …


The Toeplitz Algebra Of A Hilbert Bimodule, Neal J. Fowler, Iain Raeburn Jan 1999

The Toeplitz Algebra Of A Hilbert Bimodule, Neal J. Fowler, Iain Raeburn

Faculty of Engineering and Information Sciences - Papers: Part A

Suppose a C -algebra A acts by adjointable operators on a Hilbert A -module X. Pimsner constructed a C -algebra 𝒪 X which includes, for particular choices of X , crossed products of A by Z , the Cuntz algebras 𝒪 n , and the CuntzKrieger algebras 𝒪 B. Here we analyse the representations of the corresponding Toeplitz algebra. One consequence is a uniqueness theorem for the ToeplitzCuntz-Krieger algebras of directed graphs, which includes Cuntz’s uniqueness theorem for 𝒪.


Lie Algebras Of Cohomological Codimension One, Grant F. Armstrong, Grant Cairns, Gunky Kim Jan 1999

Lie Algebras Of Cohomological Codimension One, Grant F. Armstrong, Grant Cairns, Gunky Kim

Faculty of Engineering and Information Sciences - Papers: Part A

We show that if g is a finite dimensional real Lie algebra, then g has cohomological dimension cd(g) = dim(g) - 1 if and only if g is a unimodular extension of the two-dimensional non-Abelian Lie algebra aff.


Simulated Annealing: Searching For An Optimal Temperature Schedule, Harry Cohn, Mark James Fielding Jan 1999

Simulated Annealing: Searching For An Optimal Temperature Schedule, Harry Cohn, Mark James Fielding

Faculty of Engineering and Information Sciences - Papers: Part A

A sizable part of the theoretical literature on simulated annealing deals with a property called convergence, which asserts that the simulated annealing chain is in the set of global minimum states of the objective function with probability tending to 1. However, in practice, the convergent algorithms are considered too slow, whereas a number of nonconvergent ones are usually preferred. We attempt a detailed analysis of various temperature schedules. Examples will be given of when it is both practically and theoretically justified to use boiling, fixed temperature, or even fast cooling schedules which have a small probability of reaching global minima. …


Magnetic Circuit Of A Synchronous Reluctance Motor, P P. Ciufo, D. Platt, B S. P Perera Jan 1999

Magnetic Circuit Of A Synchronous Reluctance Motor, P P. Ciufo, D. Platt, B S. P Perera

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a model of the magnetic circuit for an axially laminated synchronous reluctance motor. The basis of the modelling technique is the determination of a value for an equivalent ``q-channel'' reluctance. This reluctance contains all the effects of paths available to q-axis flux through the rotor body. Expressions for the distribution of airgap and other motor fluxes have been developed from basic analyses involving mmf and continuity of flux. The foundations of all of these expressions are the physical parameters of the motor. The equations developed have been applied to a 370 W motor and the results from …


Instrumentation For Slope Stability - Experience From An Urban Area, P N. Flentje, R N. Chowdhury Jan 1999

Instrumentation For Slope Stability - Experience From An Urban Area, P N. Flentje, R N. Chowdhury

Faculty of Engineering and Information Sciences - Papers: Part A

This paper describes the monitoring of several existing landslides in an urban area near Wollongong in the state of New South Wales, Australia. A brief overview of topography and geology is given and reference is made to the types of slope movement, processes and causal factors. Often the slope movements are extremely slow and imperceptible to the eye, and catastrophic failures are quite infrequent. However, cumulative movements at these slower rates do, over time, cause considerable distress to structures and disrupt residential areas and transport routes. Inclinometers and piezometers have been installed at a number of locations and monitoring of …


Consideration Of Probability Assessments Relevant To Hazard And Risk For Landslides, R N. Chowdhury, P N. Flentje Jan 1999

Consideration Of Probability Assessments Relevant To Hazard And Risk For Landslides, R N. Chowdhury, P N. Flentje

Faculty of Engineering and Information Sciences - Papers: Part A

Probability of occurrence is the most important component of landslide hazard and risk and this paper outlines different approaches for its assessment. The reasons for the popularity of qualitative approaches are first outlined. Quantitative approaches can be best applied if the important influencing factors and issues are fully understood. Formal probabilistic approaches are often based on geotechnical models or on a combination of hydrological and geotechnical models. The paper also highlights the situations for which the performance function must be formulated in terms of lateral displacements rather than the conventional safety factor. Reference is then made to a procedure, based …


Quantitative Landslide Hazard Assessment In An Urban Area, Phillip N. Flentje, Robin N. Chowdhury Jan 1999

Quantitative Landslide Hazard Assessment In An Urban Area, Phillip N. Flentje, Robin N. Chowdhury

Faculty of Engineering and Information Sciences - Papers: Part A

Before decisions can be made concerning the management of sloping areas subject to landsliding, systematic approaches for hazard and risk assessment must be developed. This paper is limited to a discussion of hazard assessment and describes quantitative approaches which have been developed for existing landslides. Consideration of areas of potential landsliding is outside the scope of the paper. The approach described here is based on (a) monitoring of subsurface shear movement at instrumented sites and (b) the percentage exceedance time of cumulative rainfalls considering different selected periods of antecedent rainfall. This approach is used in conjunction with a simpler approach, …


Aspects Of Recent Landslide Research At The University Of Wollongong, Robin N. Chowdhury, Phillip N. Flentje, Chit Ko Ko Jan 1999

Aspects Of Recent Landslide Research At The University Of Wollongong, Robin N. Chowdhury, Phillip N. Flentje, Chit Ko Ko

Faculty of Engineering and Information Sciences - Papers: Part A

This paper introduces the issues which are of critical importance to landslide hazard and risk assessment and management. These include understanding of probability and consequence, the separation of the role of site-dependent factors from that of influencing/triggering natural events and the factors influencing target levels of risk. The research completed at the University of Wollongong is then outlined. This includes the development of an observational approach based on monitoring of subsurface movements at individual sites and appropriate use of rainfall data in terms of the concept of annual rainfall percentage exceedance time (ARPET). Attention is then focused on current research …


Geotechnical Assessment And Management Of 148 Landslides Triggered By A Major Storm Event In Wollongong, Australia, P N. Flentje, R N. Chowdhury Jan 1999

Geotechnical Assessment And Management Of 148 Landslides Triggered By A Major Storm Event In Wollongong, Australia, P N. Flentje, R N. Chowdhury

Faculty of Engineering and Information Sciences - Papers: Part A

On the 17th August 1998 a severe rainfall event occurred over a widespread area of the City of Wollongong. During this storm, 1 person drowned and an estimated $50 to $100 million damage was caused to the City of Wollongong. Road access to the City was cut by raised water levels and debris flows covering and or scouring road and rail routes for up to 36 hours following this event. A geotechnical team of 3, including the first author, was organised at very short notice during the response phase of the emergency operations on the early morning of the 20th …


Optimization Of Soliton Amplitude In Dispersion-Decreasing Nonlinear Optical Fibres, Ken I M Mckinnon, Noel Smyth, Annette L. Worthy Jan 1999

Optimization Of Soliton Amplitude In Dispersion-Decreasing Nonlinear Optical Fibres, Ken I M Mckinnon, Noel Smyth, Annette L. Worthy

Faculty of Engineering and Information Sciences - Papers: Part A

The compression of a cw into a periodic train of noninteracting solitons by a dispersion-decreasing fiber is investigated with a variational method. To model the evolution from the cw to the soliton train, an elliptic-function-based expression is used as the trial function in the averaged Lagrangian. Both a continuous dispersion variation and a step dispersion variation in the fiber are considered. By use of an optimization method based on the approximate variational equations, the optimal dispersion profile required for achieving maximum pulse compression in a fixed length of fiber is determined. The solutions of the approximate equations are compared with …


Landslide Risk Assessment - Development Of A Hazard Consequence Approach, Chit Ko Ko, Phillip N. Flentje, Robin N. Chowdhury Jan 1999

Landslide Risk Assessment - Development Of A Hazard Consequence Approach, Chit Ko Ko, Phillip N. Flentje, Robin N. Chowdhury

Faculty of Engineering and Information Sciences - Papers: Part A

Several Landslide Hazard and Risk Assessment methods have been developed and used in the State of New South Wales (NSW), Australia. The Rail Services Australia Geotechnical Services and the Roads and Traffic Authority of NSW have each developed Risk Assessment procedures suitable to their own specific needs. A generic risk management methodology is presented in the Australian Standard/New Zealand Standard (AS/NZS) 4360:1995. An approach similar to the (AS/NZS) 4360:1995 Risk Management Standard has been applied by a NSW State Emergency Services geotechnical team (which included one of the writers) to 191 problem sites in the Wollongong Area, following a major …


Network Reconfiguration For Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon Jan 1999

Network Reconfiguration For Load Balancing In Distribution Networks, Kashem M. Muttaqi, Velappa Ganapathy, G G. Jasmon

Faculty of Engineering and Information Sciences - Papers: Part A

Network reconfiguration of a power distribution system is an operation to alter the topological structure of distribution feeders by changing opedclosed status of sectionalising and tie switches. By transferring loads from the heavily loaded feeders to the lightly loaded ones, network reconfiguration can balance feeder loads and alleviate overload conditions of a network. The branch load-balancing index and the overall system load-balancing index are used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal configuration of load balancing. For optimal load balancing condition the branch load-balancing …


Pseudo-Shock In Supersonic Injection Feeder, Ajit R. Godbole, Peter W. Wypych, Wee King Soh, Brent Matthews Jan 1999

Pseudo-Shock In Supersonic Injection Feeder, Ajit R. Godbole, Peter W. Wypych, Wee King Soh, Brent Matthews

Faculty of Engineering and Information Sciences - Papers: Part B

The flow in a Supersonic Injection Feeder involves relatively thick boundary layers in a narrow channel. When the pressures at the extremities of such a duct are adjusted to produce a compression shock, the shock structure is radically different from a plane discontinuity. This difference arises solely due to shock wave-boundary layer interaction, and gives rise to the so-called "pseudo-shock". In this paper, results of CFD simulations of a pseudo-shock in clean gas (air) are compared with predictions of the "Diffusion" model, the "Modified-Fanno" model and with experimental results. An analysis of the effect of small particles on pseudo-shock structure …


Maintaining Transitive Closure Of Graphs In Sql, Guozhu Dong, Leonid Libkin, Jianwen Su, Limsoon Wong Jan 1999

Maintaining Transitive Closure Of Graphs In Sql, Guozhu Dong, Leonid Libkin, Jianwen Su, Limsoon Wong

Kno.e.sis Publications

It is common knowledge that relational calculus and even SQL are not expressive enough to express recursive queries such as the transitive closure. In a real database system, one can overcome this problem by storing a graph together with its transitive closure and maintaining the latter whenever updates to the former occur. This leads to the concept of an incremental evaluation system, or IES.

Much is already known about the theory of IES but very little has been translated into practice. The purpose of this paper is to fill in this gap by providing a gentle introduction to and …


Infoharness: Managing Distributed, Heterogeneous Information, Kshitij Shah, Amit P. Sheth Jan 1999

Infoharness: Managing Distributed, Heterogeneous Information, Kshitij Shah, Amit P. Sheth

Kno.e.sis Publications

Today, important information is scattered in so many places, formats, and media, that getting the right information at the right time and place is an extremely difficult task. Developing a single software product, for example, includes the creation of documents ranging from the requirements specification and project schedules to marketing presentations, multimedia tutorials, and more. Each document may be created by a different person using a different tool, and each may be stored in a different place. InfoHarness is an information integration system, platform, and tool set that addresses these problems, managing huge amounts of heterogeneous information in a distributed …


Processes Driving The Networked Economy, Amit P. Sheth, Will Van Der Aalst, I. Budak Arpinar Jan 1999

Processes Driving The Networked Economy, Amit P. Sheth, Will Van Der Aalst, I. Budak Arpinar

Kno.e.sis Publications

The authors propose that an organic workflow-process technology will power the evolution of information system architectures. The authors outline three likely stages of architectural evolution in the context of a networked economy and discuss critical gaps in the current technology with respect to their envisioned future.