Computer Sciences Commons^™

Images 2.1 : An Integrated Model Of An Arid Grazing System, Z G. Yan, K M. Wang

Resource management technical reports

The name IMAGES stands for An Integrated Model of an Arid Grazing Ecological System. The model was initiated by Dr R. Hacker in 1987-8 as an activity to (1) evaluate alternative management strategies and (2) identify key ecological processes and research priorities in shrub rangelands of Western Australia. Version 1 of the model was published in Agriculture Systems in 1991 (Hacker et al. 1991) and here after will be referred to as IMAGES 1. IMAGES 1 is a vegetation model, capable of predicting the prob ility of recruitment and mortality of the desirable species in a given vegetation type under …

Managing Multiple Information Sources Through Ontologies: Relationship Between Vocabulary Heterogeneity And Loss Of Information, Eduardo Mena, Vipul Kashyap, Arantza Illarramendi, Amit P. Sheth

Kno.e.sis Publications

The ability to deal with a huge number of independent and heterogeneous repositories is the most critical problem in Global Information Systems. One approach to enable efficient query processing is by utilizing semantic descriptions (organized as ontologies) of such repositories whenever available.

In this context semantic relationships among ontologies can be used Query Processors. Three kind of relationships are considered: synonyms and hypernyms. Using synonyms the semantic of the query is preserved; however, when synonyms are not available and hypernyms or hyponyms are used there exists some loss of information that must be measured.

Observer: An Approach For Query Processing In Global Information Systems Based On Interoperation Across Pre-Existing Ontologies, Eduardo Mena, Vipul Kashyap, Amit P. Sheth, Arantza Illarramendi

Kno.e.sis Publications

The huge number of autonomous and heterogeneous data repositories accessible on the “global information infrastructure” makes it impossible for users to be aware of the locations structure/organization, query languages and semantics of the data in various repositories. There is a critical need to complement current browsing, navigational and information retrieval techniques with a strategy that focuses on information content and semantics. In any strategy that focuses on information content, the most critical problem is that of different vocabularies used to describe similar information across domains. We discuss a scalable approach for vocabulary sharing. The objects in the repositories are represented …

Proof Strategies For Hardware Verification, Robert Eastham, Krishnaprasad Thirunarayan

Kno.e.sis Publications

Ascertaining correctness of digital hardware designs through simulation does not scale-up for large designs because of the sheer combinatorics of the problem. Formal verification of hardware designs holds promise because its computational complexity is of the order of number of different types of components (and not number of components in the design). This approach requires the specification of the behavior and the design in a formal language, and reason with them using a theorem prover. In this paper we attempt to develop a methodology for writing and using these specifications for some important classes of hardware circuits. We examine digital …

Semantic And Schematic Similarities Between Database Objects: A Context-Based Approach, Vipul Kashyap, Amit P. Sheth

Kno.e.sis Publications

In a multidatabase system, schematic conflicts between two objects are usually of interest only when the objects have some semantic similarity. We use the concept of semantic proximity, which is essentially an abstraction/mapping between the domains of the two objects associated with the context of comparison. An explicit though partial context representation is proposed and the specificity relationship between contexts is defined. The contexts are organized as a meet semi-lattice and associated operations like the greatest lower bound are defined. The context of comparison and the type of abstractions used to relate the two objects form the basis of a …

Spieltheorie, Alexander Chocholaty, Pascal Hitzler

Computer Science and Engineering Faculty Publications

No abstract provided.

Rex ' 96 : An Expert Guide To Revegetation, David Bicknell

Journal of the Department of Agriculture, Western Australia, Series 4

Agriculture Western Australia has provided coordination and technical input to a powerful source of information on plants for Australian conditions. David Bicknell outlines some of its features and uses.

Farmers, local government, advisers and even gardeners often have trouble finding the right plant for the right place for a given purpose. Rather than spend a lot of time, money and effort looking through scattered sources of information, many people stick with a limited number of species year after year. This neglects plants that may be much better suited to the purpose, and also fails to develop Australia's huge range of …

Simulation Modeling Within Workflow Technology, John A. Miller, Amit P. Sheth, Krzysztof J. Kochut, Xuzhong Wang, Arun Murugan

Kno.e.sis Publications

This paper presents an approach for integrating simulation modeling and analysis capabilities within the workflow management system (WFMS) being developed in the Large Scale Distributed Information Systems (LSDIS) Lab at the University of Georgia. Simulation modeling can be used for studying the efficiency of workflow designs as well as studying the general performance and reliability of WFMSs. We also discuss the importance of using sophisticated monitoring and animation capabilities, and the use of workflow management technology to advance simulation technology itself. Finally, we demonstrate a sample simulation where tasks and task managers are simulated.

On The Equivalence Of Upward And Downward Inheritance Reasoners, Krishnaprasad Thirunarayan

Kno.e.sis Publications

In this paper, we analyze systematically the downward (property flow) and the upward (individual flow) views of inheritance for different categories of inheritance networks. We observe that both these views assign the same meaning to tree-structured hierarchies, and explain the divergence in the interpretation of more general networks in terms of their expressive power. This simple analysis sheds light on the inherent nature of nonmonotonic inheritance and can form the basis for the design of efficient algorithms for certain classes of queries. In addition, we describe the notion of preferential inheritance to specify additional conflict resolution information that can be …

Power Systems Marginal Cost Curve And Its Applications, Shaojun Wang, S. M. Shahidehpour, Nian-De Xiang

Kno.e.sis Publications

This paper presents a forward recursive procedure to calculate the expected system marginal cost curve (EMC). The EMC formulation allows for multi-state and multi-block dispatch of generating units and is used to determine the optimal energy of pumped-storage units. A new approach is developed to compute the first and second derivatives of the expected generation energy of a thermal unit with respect to the capacity of all thermal units in the system. The salient feature of the proposed approach is that it applies to hydro-thermal systems with multiple limited-energy hydro units.

Interview: Brenda Laurel, Jason Challas

SWITCH

This interview with Brenda Laurel, Virtual Reality (VR) author and thinker, discusses the applications and challenges of VR. Creating an emphatic experience using VR technology is possible, but the challenge lies in designing an environment that models the senses to stimulate emotions. VR enables experiences of different genders, but physiological differences between the sexes exist and are important to understand. However, technology used to create the environment and simulation of physical objects in VR is only in the developmental stage. Laurel believes in the importance of keeping the mind grounded in the physical body, in order to strengthen the appreciation …

Predicting Conserved Water-Mediated Interactions In Protein Active Sites, Michael L. Raymer, Sridhar Venkataraman, William F. Punch, Erik D. Goodman, Brenda Kuhn

Kno.e.sis Publications

No abstract provided.

Physiologically-Based Pharmacokinetic Modeling Of Skin Absorption Using Dermal Subcompartments, Richard L. Bookout Jr.

Theses and Dissertations

Dermal penetration of chemicals and drugs is important to both toxicologists and pharmacologists. Drug developers try to enhance and environmental professionals try to limit penetration of chemicals through the skin. Both can use predictive biologically-based mathematical models to assist in understanding the processes involved. When these models are based on physiological and biochemical parameters which can be measured in the laboratory, they can be extremely useful. Appropriately validated models based on first principles can be predictive of human exposures when the processes involved are adequately understood. In this thesis we develop four new physiologically-based pharmacokinetic (PBPK) models to predict blood …

Transitions In Masculinity And Hemingway's Developed "Code", Daniel Polk

Honors Theses

The "Hemingway Code" is much more than two words that fit nicely together for a scholar's usage; the words signify a much deeper championing of masculinity, almost a haunting presence. For Ernest Hemingway living life every day, every moment with its fullest masculine fervor, became an obsession, a never-ending quest to be at one with the attitude of never complaining, never crying out, panicking, thinking too much, or regretting. To live a manly life in a series of tactical victories, performed with steadfast ritualistic mannerisms, is to embody masculinity, and therefore the "Hemingway Code."

A Meta-Interpreter For Circuit-Extraction, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The design of a VLSI circuit consists of a description of the circuit in terms of its components and subcomponents, at various levels of detail. To verify that the layout of a VLSI circuit conforms to its design, one needs to work backwards from the lowest-level description of the circuit and recognize the higher-level components it constitutes. This paper is concerned with the application of logic programming techniques in the formal verification of the structural correctness of the VLSI circuit layouts. In particular, we review Michael Dukes' Generalized Extraction System (1990) that compiles design descriptions into a set of extraction …

Nonrecursive Incremental Evaluation Of Datalog Queries, Guozhu Dong, Jianwen Su, Rodney Topor

Kno.e.sis Publications

We consider the problem of repeatedly evaluating the same (computationally expensive) query to a database that is being updated between successive query requests. In this situation, it should be possible to use the difference between successive database states and the answer to the query in one state to reduce the cost of evaluating the query in the next state. We use nonrecursive Datalog (which are unions of conjunctive queries) to compute the differences, and call this process “incremental query evaluation using conjunctive queries”. After formalizing the notion of incremental query evaluation using conjunctive queries, we give an algorithm that constructs, …

The "Infoharness" Information Integration Platform, Leon Shklar, Satish Thatte, Howard Marcus, Amit P. Sheth

Kno.e.sis Publications

The "InfoHarness" information integration platform, tools, and services being developed at Bellcore are aimed at providing integrated and rapid access to huge amounts of heterogeneous information independent of the type, representation, and location of information. InfoHarness provides advanced search and browsing capabilities without imposing the burden of restructuring, reformatting or relocating information on information suppliers or creators. This is achieved through object-oriented encapsulation of information and the associated meta-information (e.g., type, location, access rights, owner, creation date, etc.). The meta-information extraction methods ensure rapid and largely automatic creation of information repositories. A gateway that supports access to InfoHarness repositories from …

Using Tickets To Enforce The Serializability Of Multidatabase Transactions, Dimitrios Georgakopoulos, Marek Rusinkiewicz, Amit P. Sheth

Kno.e.sis Publications

To enforce global serializability in a multidatabase environment the multidatabase transaction manager must take into account the indirect (transitive) conflicts between multidatabase transactions caused by local transactions. Such conflicts are difficult to resolve because the behavior or even the existence of local transactions is not known to the multidatabase system. To overcome these difficulties, we propose to incorporate additional data manipulation operations in the subtransactions of each multidatabase transaction. We show that if these operations create direct conflicts between subtransactions at each participating local database system, indirect conflicts can be resolved even if the multidatabase system is not aware of …

Semantics-Based Information Brokering: A Step Towards Realizing The Infocosm, Vipul Kashyap, Amit P. Sheth

Kno.e.sis Publications

The rapid advances in computer and communication technologies, and their merger, is leading to a global information market place. It will consist of federations of very large number of information systems that will cooperate to varying extents to support the users' information needs. We propose an architecture which may facilitate meeting these needs. It consists of three main components: information providers, information brokers and information consumers. We also propose an approach to information brokering. We discuss two of it's tasks: information resource discovery, which identities relevant information sources for a given query, and query processing, which involves the generation of …

Specifying And Enforcing Intertask Dependencies, Paul Attie, Munindar Singh, Amit P. Sheth, Marek Rusinkiewicz

Kno.e.sis Publications

Extensions of the traditional atomic transaction model are needed to support the development of multi-system applications or workflows that access heterogeneous databases and legacy application systems. Most extended transaction models use conditions involving events or dependencies between transactions. Intertask dependencies can serve as a uniform framework for defining extended transaction models. In this paper we introduce event attributes needed to determine whether a dependency is enforceable and to properly schedule events in extended transaction models. Using these attributes and a formalization of a dependency into the temporal logic CTL, we can automatically synthesize an automaton that captures the computations that …

A Framework For Controlling Cooperative Agents, Kuo-Chu Lee, William H. Mansfield, Amit P. Sheth

Kno.e.sis Publications

Presents an overview of the ITX (Interacting Transaction) system, which supports complex interactions among cooperating agents in the presence of user interventions that change application objectives and system failures. The system's components and its unique fixed-point criterion for feedback control of iterative interactions are described. An example of a simplified multimedia teleconferencing application is discussed to illustrate the features of the ITX system.

Digital Information In The Peel-Harvey Catchment Area, Dennis Van Gool

Agriculture reports

This paper presents a summary of the main features of the digital mapping data available in the Peel-Harvey Catchment area. This type of information is essential for Geographic Information System (GIS) users to assess projects involving the use of digital data such as plotting of mapped themes, topological overlays, area calculations and reporting.

So Far (Schematically) Yet So Near (Semantically), Amit P. Sheth, Vipul Kashyap

Kno.e.sis Publications

In a multidatabase system, schematic conflicts between two objects are usually of interest only when the objects have some semantic affinity. In this paper we try to reconcile the two perspectives. We first define the concept of semantic proximity and provide a semantic taxonomy. We then enumerate and classify the schematic and data conflicts. We discuss possible semantic similarities between two objects that have various types of schematic and data conflicts. Issues of uncertain information and inconsistent information are also addressed.

On Transactional Workflows, Amit P. Sheth, Marek Rusinkiewicz

Kno.e.sis Publications

The basic transaction model has evolved over time to incorporate more complex transactions structures and to take the advantage of semantics of higher-level operations that cannot be seen at the level of page reads and writes. Well known examples of such extended transaction models include nested and multi-level transactions. A number of relaxed transaction models have been defined in the last several years that permit a controlled relaxation of the transaction isolation and atomicity to better match the requirements of various database applications. Correctness criteria other than global serializability have also been proposed. Several examples of extended/relaxed transaction models are …

Lecture Notes For Nscp-Funded Short Course - Remote Sensing Training For Resource Officers And Farmers, Western Australian Department Of Agriculture

Soil conservation survey collection

The aim of this course is to provide an introduction to remote sensing, and knowledge and practice in image processing techniques for the extraction of information from remotely sensed data. Aerial photography is the original form of earth remote sensing, and is still a widely used and important data source for many purposes. This course is directed principally at the analysis of digital image data recorded by satellite or airborne platforms. Remote sensing is considered to be the methodology of collecting and interpreting target information over a broad range of the electromagnetic spectrum.

Abduction In Annotated Logic Programming, Krishnaprasad Thirunarayan

Kno.e.sis Publications

The author investigates techniques to make the logic programming paradigm more expressive for knowledge representation, while simultaneously retaining the computational advantages of efficiency and simplicity. He extends the annotated language of K. Thirunarayan and K. Kifer (1989) in various directions to obtain an enriched representation language. In particular, rule bodies are permitted to be a conjunction of literals, and the rules to be recursive. A class of annotated logic programs called the stratified programs is identified which can be given a unique supported minimal Herbrand model as their meaning. Abductive reasoning is integrated into this annotated logic framework. The notion …

Using Flexible Transactions To Support Multisystem Telecommunication Applications, Mansoor Ansari, Linda Ness, Marek Rusinkiewicz, Amit P. Sheth

Kno.e.sis Publications

Service order provisioning is an important telecommunication application that automates the process of providing telephone services in response to the customer requests. It is an example of a multi-system application that requires access to multiple, independently developed application systems and their databases. In this paper, we describe the design and implementation of a prototype system1 that supports the execution of the Flexible Transactions and its use to develop the service order provisioning application. We argue that such approach may be used to support the development of multi-system, flow-through processing applications in a systematic and organized manner. Its advantages include fast …

Algorithms For Structural Schema Integration, James Geller, Ashish Mehra, Yehoshua Perl, Erich Neuhold, Amit P. Sheth

Kno.e.sis Publications

Current view and schema integration methodologies are driven by semantic considerations, and allow integration of objects only if that is valid from semantic and structural viewpoints. We had introduced a new integration technique called structural integration. It permits integration of objects that have structural similarities, even if they differ semantically. This technique uses the object-oriented Dual Model which separates the representation of structure and semantics.

In this paper we introduce algorithms for structural integration. We apply these algorithms to integrate two views of a large university database schema which had significant structural similarities but differed semantically.

Executing Multidatabase Transactions, Mansoor Ansari, Marek Rusinkiewicz, Linda Ness, Amit P. Sheth

Kno.e.sis Publications

In a multidatabase environment, the traditional transaction model has been found to be too restrictive. Therefore, several extended transaction models have been proposed in which some of the requirements of transaction, such as isolation or atomicity, are optional. The authors describe one of such extensions, the flexible transaction model and discuss the scheduling of transactions involving multiple autonomous database systems managed by heterogeneous DBMS.

The scheduling algorithm for flexible transactions is implemented using L.0, a logically parallel language which provides a framework for concisely specifying the multidatabase transactions and for scheduling them. The key aspects of a flexible transaction specification, …

Specifying Interdatabase Dependencies In A Multidatabase Environment, Marek Rusinkiewicz, Amit P. Sheth, George Karabatis

Kno.e.sis Publications

The problem of interdatabase dependencies and the effect they have on applications updating interdependent data are addressed. A model that allows specifications of constraints among multiple databases in a declarative fashion is proposed. The separation of the constraints from the application programs facilitates the maintenance of data constraints and allows flexibility in their implementation. It allows investigation of various mechanisms for enforcing the constraints, independently of the application programs. By grouping the constraints together, it is possible to check their completeness and discover possible contradictions among them. The concepts of polytransactions, which use interdatabase dependencies to generate a series of …