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Exception Handling In Workflow Systems, Zongwei Luo, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller Sep 2000

Exception Handling In Workflow Systems, Zongwei Luo, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller

Kno.e.sis Publications

In this paper, defeasible workflow is proposed as a framework to support exception handling for workflow management. By using the “justified” ECA rules to capture more contexts in workflow modeling, defeasible workflow uses context dependent reasoning to enhance the exception handling capability of workflow management systems. In particular, this limits possible alternative exception handler candidates in dealing with exceptional situations. Furthermore, a case-based reasoning (CBR) mechanism with integrated human involvement is used to improve the exception handling capabilities. This involves collecting cases to capture experiences in handling exceptions, retrieving similar prior exception handling cases, and reusing the exception handling experiences …


Dimensionality Reduction Using Genetic Algorithms, Michael L. Raymer, William F. Punch, Erik D. Goodman, Leslie A. Kuhn, Anil K. Jain Jul 2000

Dimensionality Reduction Using Genetic Algorithms, Michael L. Raymer, William F. Punch, Erik D. Goodman, Leslie A. Kuhn, Anil K. Jain

Kno.e.sis Publications

Pattern recognition generally requires that objects be described in terms of a set of measurable features. The selection and quality of the features representing each pattern affect the success of subsequent classification. Feature extraction is the process of deriving new features from original features to reduce the cost of feature measurement, increase classifier efficiency, and allow higher accuracy. Many feature extraction techniques involve linear transformations of the original pattern vectors to new vectors of lower dimensionality. While this is useful for data visualization and classification efficiency, it does not necessarily reduce the number of features to be measured since each …


On-Line Bayesian Speaker Adaptation By Using Tree-Structured Transformation And Robust Priors, Shaojun Wang, Yunxin Zhao Jun 2000

On-Line Bayesian Speaker Adaptation By Using Tree-Structured Transformation And Robust Priors, Shaojun Wang, Yunxin Zhao

Kno.e.sis Publications

This paper presents new results by using our previously proposed on-line Bayesian learning approach for affine transformation parameter estimation in speaker adaptation. The on-line Bayesian learning technique allows updating parameter estimates after each utterance and it can accommodate flexible forms of transformation functions as well as prior probability density functions. We show through experimental results the robustness of heavy tailed priors to mismatch in prior density estimation. We also show that by properly choosing the transformation matrices and depths of hierarchical trees, recognition performance improved significantly.


Local Properties Of Query Languages, Guozhu Dong, Leonid Libkin, Limsoon Wong May 2000

Local Properties Of Query Languages, Guozhu Dong, Leonid Libkin, Limsoon Wong

Kno.e.sis Publications

In this paper we study the expressiveness of local queries. By locality we mean — informally — that in order to check if a tuple belongs to the result of a query, one only has to look at a certain predetermined portion of the input. Examples include all relational calculus queries. We start by proving a general result describing outputs of local queries. This result leads to many easy inexpressibility proofs for local queries. We then consider a closely related property, namely, the bounded degree property. It describes the outputs of local queries on structures that locally look “simple.” Every …


The Space Of Jumping Emerging Patterns And Its Incremental Maintenance, Jinyan Li, Kotagiri Ramamohanarao, Guozhu Dong Jan 2000

The Space Of Jumping Emerging Patterns And Its Incremental Maintenance, Jinyan Li, Kotagiri Ramamohanarao, Guozhu Dong

Kno.e.sis Publications

The concept of jumping emerging patterns (JEPs) has been proposed to describe those discriminating features which only occur in the positive training instances but do not occur in the negative class at all; JEPs have been used to construct classifiers which generally provide better accuracy than the state-of-the-art classifiers such as C4.5. The algorithms for maintaining the space of jumping emerging patterns (JEP space) are presented in this paper. We prove that JEP spaces satisfy the property of convexity. Therefore JEP spaces can be concisely represented by two bounds: consisting respectively of the most general elements and the most specific …


Separating Auxiliary Arity Hierarchy Of First-Order Incremental Evaluation Using (3+1)-Ary Input Relations, Guozhu Dong, Louxin Zhang Jan 2000

Separating Auxiliary Arity Hierarchy Of First-Order Incremental Evaluation Using (3+1)-Ary Input Relations, Guozhu Dong, Louxin Zhang

Kno.e.sis Publications

Presents a first-order incremental evaluation system that uses first-order queries to maintain a database view defined by a non-first-order query. Reduction of the arity of queries to understand the power of foies; Use of a key lemma for proving a query which encodes the multiple parity problem.


Imprecise Answers In Distributed Environments: Estimation Of Information Loss For Multi-Ontology Based Query Processing, Eduardo Mena, Vipul Kashyap, Arantza Illarramendi, Amit P. Sheth Jan 2000

Imprecise Answers In Distributed Environments: Estimation Of Information Loss For Multi-Ontology Based Query Processing, Eduardo Mena, Vipul Kashyap, Arantza Illarramendi, Amit P. Sheth

Kno.e.sis Publications

The World Wide Web is fast becoming a ubiquitous computing environment. Prevalent keyword-based search techniques are scalable, but are incapable of accessing information based on concepts. We investigate the use of concepts from multiple, real-world pre-existing, domain ontologies to describe the underlying data content and support information access at a higher level of abstraction. It is not practical to have a single domain ontology to describe the vast amounts of data on the Web. In fact, we expect multiple ontologies to be used as different world views and present an approach to "browse" ontologies as a paradigm for information access. …


Optimization Techniques For Data Intensive Decision Flows, Richard Hull, Francois Llirbat, Bharat Kumar, Gang Zhou, Guozhu Dong, Jianwen Su Jan 2000

Optimization Techniques For Data Intensive Decision Flows, Richard Hull, Francois Llirbat, Bharat Kumar, Gang Zhou, Guozhu Dong, Jianwen Su

Kno.e.sis Publications

For an enterprise to take advantage of the opportunities afforded by electronic commerce it must be able to make decisions about business transactions in near-real-time. In the coming era of segment-of-one marketing, these decisions will be quite intricate, so that customer treatments can be highly personalized, reflecting customer preferences, the customer's history with the enterprise, and targeted business objectives. This paper describes a paradigm called “decision flows” for specifying a form of incremental decision-making that can combine diverse business factors in near-real-time.

This paper introduces and empirically analyzes a variety of optimization strategies for decision flows that are “data-intensive”, i.e. …


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 …


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. …


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. …


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.


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 …


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.


Logical Information Modeling Of Web-Accessible Heterogeneous Digital Assets, Kshitij Shah, Amit P. Sheth Apr 1998

Logical Information Modeling Of Web-Accessible Heterogeneous Digital Assets, Kshitij Shah, Amit P. Sheth

Kno.e.sis Publications

This paper introduces the MREF framework for representing and correlating information at a higher semantic level than is possible with Web-based information systems today. The role that metadata plays in this framework is described, together with a metadata based infrastructure to support our media independent information correlation paradigm. To keep it consistent with evolving standards, broader acceptance and ease of implementation, MREF abstraction is structured on top of RDF and XML. Its central role in the context of the InfoQuilt system, for exploiting heterogeneous digital media using a federated and scalable architecture, is briefly described.


Zebra Image Access System, Srilekha Mudumbai, Kshitij Shah, Amit P. Sheth, Krishnan Parasuraman, Clemens Bertram Feb 1998

Zebra Image Access System, Srilekha Mudumbai, Kshitij Shah, Amit P. Sheth, Krishnan Parasuraman, Clemens Bertram

Kno.e.sis Publications

The ZEBRA system, which is part of the VisualHarness platform for managing heterogeneous data, supports three types of access to distributed image repositories: keyword based, attribute based, and image content based. A user can assign different weights (relative importance) to each of the three types, and within the last type of access, to each of the image properties. The image based access component (IBAC) supports access based on computable image properties such as those based on spatial domain, frequency domain or statistical and structural analysis. However, it uses a novel black box approach of utilizing a Visual Information Retrieval (VIR) …


Interestingness Of Discovered Association Rules In Terms Of Neighborhood-Based Unexpectedness, Guozhu Dong, Jinyan Li Jan 1998

Interestingness Of Discovered Association Rules In Terms Of Neighborhood-Based Unexpectedness, Guozhu Dong, Jinyan Li

Kno.e.sis Publications

One of the central problems in knowledge discovery is the development of good measures of interestingness of discovered patterns. With such measures, a user needs to manually examine only the more interesting rules, instead of each of a large number of mined rules. Previous proposals of such measures include rule templates, minimal rule cover, actionability, and unexpectedness in the statistical sense or against user beliefs.

In this paper we will introduce neighborhood-based interestingness by considering unexpectedness in terms of neighborhood-based parameters. We first present some novel notions of distance between rules and of neighborhood of rules. The neighborhood-based interestingness of …


From Contemporary Workflow Process Automation To Adaptive And Dynamic Work Activity Coordination And Collaboration, Amit P. Sheth Sep 1997

From Contemporary Workflow Process Automation To Adaptive And Dynamic Work Activity Coordination And Collaboration, Amit P. Sheth

Kno.e.sis Publications

The article outlines a research agenda for researchers in the area of workflow. We believe that today's workflow systems should evolve to what is termed as work coordination and collaboration systems (WCCSs). A WCCS will: (a) adapt to various changes in the organization (including its interactions with external organizations) and the organizational processes by being able to change the process definitions as well as change the processes and component activities while they are being enacted or executed; and (b) support a unified framework for managing coordination, collaboration, and information based decision making activities that naturally occur as part of organizational …


A Vhdl-93 Hardware Description Browser, Laura C. Debrock, Krishnaprasad Thirunarayan May 1997

A Vhdl-93 Hardware Description Browser, Laura C. Debrock, Krishnaprasad Thirunarayan

Kno.e.sis Publications

This paper describes the design and implementation of the VHDL-93 Hardware Description Browser, which is a tool for the intelligent retrieval of information from VHDL designs. The Browser consists of two UNIX processes: a TCL/TK Graphical User Interface and a Prolog search engine. The GUI elicits queries from the user and submits them to the Prolog search engine via a two-way communication pipe. The search engine satisfies queries by traversing a forest of parse trees corresponding to the associated VHDL designs. The results are then sent to the GUI for posting.

Two public-domain tools were used to implement the Browser: …


The Carnot Heterogeneous Database Project: Implemented Applications, Munindar Singh, Phil Cannata, Michael N. Huhns, Nigel Jacobs, Tomasz Ksiezyk, Kayliang Ong, Amit P. Sheth, Christine Tomlinson, Darrell Woelk Apr 1997

The Carnot Heterogeneous Database Project: Implemented Applications, Munindar Singh, Phil Cannata, Michael N. Huhns, Nigel Jacobs, Tomasz Ksiezyk, Kayliang Ong, Amit P. Sheth, Christine Tomlinson, Darrell Woelk

Kno.e.sis Publications

The Carnot project was an ambitious research project in heterogeneous databases. It integrated a variety of techniques to address a wide range of problems in achieving interoperation in heterogeneous environments. Here we describe some of the major implemented applications of this project. These applications concern(a) accessing a legacy scientific database, (b) automating a workflow involving legacy systems, (c) cleaning data, and (d) retrieving semantically appropriate information from structured databases in response to text queries. These applications support scientific decision support, business process management, data integrity enhancement, and analytical decision support, respectively. They demonstrate Carnot‘s capabilities for (a) heterogeneous query processing, …


Characterizing A Portable Subset Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing Apr 1997

Characterizing A Portable Subset Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing

Kno.e.sis Publications

Goossens defined a structural operational semantics for a subset of VHDL-87 and proved that the parallelism present in VHDL is benign. We extend this work to include VHDL-93 features such as shared variables and postponed processes that change the underlying semantic model. In the presence of shared variables, nondeterministic execution of VHDL-93 processes destroys the unique meaning property. We identify and characterize a class of portable VHDL-93 descriptions for which unique meaning property can be salvaged. Our specification can serve as a correctness criteria for a VHDL-93 simulator.


Some Relationships Between Foies And Sigma 1 1 Arity Hierarchies, Guozhu Dong, Limsoon Wong Feb 1997

Some Relationships Between Foies And Sigma 1 1 Arity Hierarchies, Guozhu Dong, Limsoon Wong

Kno.e.sis Publications

No abstract provided.


Structural Issues In Active Rule Systems, James Bailey, Guozhu Dong, Kotagiri Ramamohanarao Jan 1997

Structural Issues In Active Rule Systems, James Bailey, Guozhu Dong, Kotagiri Ramamohanarao

Kno.e.sis Publications

Active database systems enhance the functionality of traditional databases through the use of active rules or ‘triggers’. There is little consensus, though, on what components should be included in a rule system. In this paper, the expressive power of some simple active database rule systems is examined and the effect of choosing different features studied. Four important parameters of variation are presented, namely the rule language, the external query language, the meta rule language and the pending rule structure. We show that each of these is highly influential in determining the expressiveness of the rule system as a whole, and …


An Error Handling Framework For The Orbwork Workflow Enactment Service Of Meteor, Davasish Worah, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller Jan 1997

An Error Handling Framework For The Orbwork Workflow Enactment Service Of Meteor, Davasish Worah, Amit P. Sheth, Krzysztof J. Kochut, John A. Miller

Kno.e.sis Publications

Workflow Management Systems (WFMSs) can be used to re-engineer, streamline, automate, and track organizational processes involving humans and automated information systems. However, the state-of-the-art in workflow technology suffers from a number of limitations that prevent it from being widely used in large-scale mission critical applications. Error handling is one such issue. What makes the task of error handling challenging is the need to deal with errors that appear in various components of a complex distributed application execution environment, including various WFMS components, workflow application tasks of different types, and the heterogeneous computing infrastructure.

In this paper, we discuss a top-down …


Algorithms For Adapting Materialised Views In Data Warehouses, Mukesh Mohania, Guozhu Dong Dec 1996

Algorithms For Adapting Materialised Views In Data Warehouses, Mukesh Mohania, Guozhu Dong

Kno.e.sis Publications

In this paper we consider the problem of materialised view adaptation in data warehouses. Materialised views are important in data warehousing where they are used to speed up query processing on large amounts of data. User requirements change over time, which may change the definitions of views dynamically. For such situations, the question arises whether the materialised views should be recomputed from scratch for every change in the definition or they should be obtained by adapting old materialised views. Changes to a view definition may be expensive, if the view is recomputed from scratch. Therefore, it is worthwhile to examine …


On The Portability Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing Oct 1996

On The Portability Of Behavioral Vhdl-93, Krishnaprasad Thirunarayan, Robert Ewing

Kno.e.sis Publications

Goossens defined a structural operational semantics for a subset of VHDL-87 and proved that the parallelism present in VHDL is benign. We extend this work to include shared variables in VHDL-93 that changes the underlying semantic model. In the presence of shared variables, non-deterministic execution of VHDL-93 processes destroys the unique meaning property. We identify and characterize a class of portable VHDL-93 descriptions for which unique meaning property can be salvaged.