Computer Sciences Commons^™

User-Database Interface: The Effect Of Abstraction Levels On Query Performance, Hock Chuan Chan, Kwok Kee Wei, Keng Siau

Research Collection School Of Computing and Information Systems

A common classification of data models is based on their abstraction levels: physical, logical and conceptual. The user-database interaction can be similarly classified. For the conceptual-level interaction, the user and the database exchange information on the user's world, e.g., information of entities, relationships, and attributes. For the logical-level interaction, the user and the database communicate based on concepts in the database system, e.g., relations and join operations. We expect users to be familiar with concepts in their world but not the concepts in the database system. This is especially so for infrequent or naive database users. The conceptual level should …

Query Optimization And Processing In Federated Database Systems, Ee Peng Lim, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

No abstract provided.

Multiple Query Optimization With Depth-First Branch-And-Bound, Ahmet Cosar, Ee Peng Lim, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

In certain database applications such as deductive databases, batch query processing, and recursive query processing etc., a single query can be transformed into a set ofclosely related database queries. Great benefits can be obtained by executing a group of related queries all together in a single unijied multi-plan instead of executing each query separately. In order to achieve this, Multiple Query Optimization (MQO) identifies common task(s) (e.g. common subezpressions, joins, etc.) among a set of query plans and creates a single unified plan (multiplan) which can be executed to obtain the required outputs forall queries at once. In this paper, …

Establishing A Distributed Processing And Distributed Database Environment For Intergraph Mge & Orscle Products, Praveen Chandrasekhar

Electronic Dissertations and Theses

The department of Agricultural Economics undertake various government contracts for GIS based applications. Currently, they have multi-year contracts with the Louisiana Department of Health and Hospitals (LDHH). This contract is carried out in the Agricultural Economics Geographical Information System lab (AEGIS). One part of the contract is to integrate a heterogenous system comprising of PCs and Intergraph workstations so that the PC can share the data or Microstation Geographical information system Environment (MGE) and ORACLE based applications. Since the Department also undertakes other contracts which requires them to use ARC/INFOR as the front-end while the data would reside in ORACLE …

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 …

Entity Identification In Database Integration: An Evidential Reasoning Approach, Ee Peng Lim, Jaideep Srivastava

Research Collection School Of Computing and Information Systems

Entity identification is the problem of matching object instances from different databases which correspond to the same real-world entity. In this paper, we present a 2-step entity identification process in which attributes for matching tuples may be missing in certain tuples, and thus need to be derived prior to the matching. To match tuples, we require identity rules which specify the conditions to be satisfied by a pair of tuples, from different databases, before they can be considered as modeling the same real-world entity. We also introduce ILFD's (instance-level functional dependencies) as a form of inference rules which derive the …

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 …

Memory-Adaptive External Sorting, Hwee Hwa Pang, Michael J. Carey, Miron Livny

Research Collection School Of Computing and Information Systems

In real-time and goal-oriented database systems, the amount of memory assigned to queries that sort or join large relations may fluctuate due to contention from other higher priority transactions. This study focuses on techniques that enable external sorts both to reduce their buffer usage when they lose memory, and to effectively utilize any additional buffers that are given to them. We also show how these techniques can be extended to work with sort-merge joins. A series of experiments confirms that our proposed techniques are useful for sorting and joining large relations in the face of memory fluctuations.

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.

Ccis Networking - July 1993, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.

A Decision Criteria To Select An Associative-Memory Organization That Minimizes The Execution Time Of A Mix Of Associative-Search Operations, David W. Banton

Theses and Dissertations

The dissertation develops a decision criteria to select an associative-memory organization that minimizes the execution time of a mix of associative-search operations and a decision criteria to estimate the layout dimensions of each organization for a specified memory size. The dissertation reclassifies Feng's associative-search operations into three hardware-influenced categories: bit-position independent (BPI), record-content independent (RCI); bit-position dependent (BPD), RCI; and BPD, record-content dependent (RCD). It develops a relationship between the categories and three associative-memory organizations: the CAM, the bit-serial word-parallel associative memory (BSWPAM) , and the extreme-search associative memory (ESAM). A version of the CAM, three versions of the BSWPAM, …

Partially Preemptible Hash Joins, Hwee Hwa Pang, Michael J. Carey, Miron Livny

Research Collection School Of Computing and Information Systems

With the advent of real-time and goal-oriented database systems, priority scheduling is likely to be an important feature in future database management systems. A consequence of priority scheduling is that a transaction may lose its buffers to higher-priority transactions, and may be given additional memory when transactions leave the system. Due to their heavy reliance on main memory, hash joins are especially vulnerable to fluctuations in memory availability. Previous studies have proposed modifications to the hash join algorithm to cope with these fluctuations, but the proposed algorithms have not been extensively evaluated or compared with each other. This paper contains …

Federated Autonomous Databases: Project Overview, Satya Prabhakar, Jiandong Huang, James Richardson, Jaideep Srivastava, Ee Peng Lim, Sham Navathe, Ashok Savarase, Mark Foresti

Research Collection School Of Computing and Information Systems

The paper presents an overview of an ongoing research program, Federated Autonomous Databases, sponsored by Rome Laboratory (US Air Force) and conducted by Honeywell in collaboration with the University of Minnesota and Georgia Institute of Technology. This program is exploratory in nature and is aimed at understanding and solving, within the scope of the program definition, the problem of providing integrated access to distributed, heterogeneous and autonomous databases.

Entity Identification In Database Integration, Ee Peng Lim, Jaideep Srivastava, Satya Prabhakar, James Richardson

Research Collection School Of Computing and Information Systems

The objective of entity identification is to determine the correspondence between object instances from more than one database. Entity identification at the instance level, assuming that schema level heterogeneity has been resolved a priori, is examined. Soundness and completeness are defined as the desired properties of any entity identification technique. To achieve soundness, a set of identity and distinctness rules are established for entities in the integrated world. The use of extended key, which is the union of keys, and possibly other attributes, from the relations to be matched, and its corresponding identify rule are proposed to determine the equivalence …

A Distributed Object-Oriented Database Application Design, Hsin-Feng Edward Wu

Theses and Dissertations

The purpose of this study is to analyze and develop a distributed object-oriented database management system (DOODBMS) application to support parallel software development of the Parallel Algorithms and Applications Group (PAAG) at AFIT. By following the software lifecycle of object-oriented paradigm, this thesis investigation is intended to generate requirements analysis, design, implementation, user interface design and implementation, and integration of the database application with the user interface. ITASCA, an existing DOODBMS platform, has been chosen to prototype the application for its distribution functionalities and object-oriented modeling power. The user interface of the database application is based on X-window OSF/Motif front-end …

Computer Implementation Of Mason's Rule And Software Development Of Stochastic Petri Nets, Xiaoyong Zhao

Theses

A symbolic performance analysis approach for discrete event systems can be formulated based on the integration of Petri nets and Moment Generating Function concepts [1-3]. The key steps in the method include modeling a system with arbitrary stochastic Petri nets (ASPN), generation of state machine Petri nets with transfer functions, derivation of equivalent transfer functions, and symbolic derivation of transfer functions to obtain the performance measures. Since Mason's rule can be used to effectively derive the closed-form transfer function, its computer implementation plays a very important role in automating the above procedure. This thesis develops the computer implementation of Mason's …

Protocol Conformance Test Generation Using Circular Uio With Overlapping, Sesharao Patchipala

Theses

The purpose of the protocol conformance testing is to ensure that protocol implementations are consistent with their specifications. After the U-method was introduced, several test methods based on the Unique Input/Output (UI0) sequences which were the main concept in the U-method have been proposed, namely, the RCP-method, MUIO-method, MUIO with overlapping method, B-method, C-method. A good test sequence must be short and have wide fault coverage. By comparing the test sequences generated by the above test methods based on experimental results, reveals that the test sequences by the MUIO with overlapping method are the worst in quality but their lengths …

Systems Integration In Pharmaceutical Industry Using Object-Oriented Expert System Technology, Korrapolu Reddy

Theses

SPHINX is an object-oriented expert system addressed to solve the burning problems of pharmaceutical industry. SPHINX stands for Systems integration in PHarmaceutical INdustry using object-oriented eXpert system technology.

Various problems that American pharmaceutical industries are facing have been explained. Using the revolutionary object-oriented concepts and the powerful expert systems technology, it has been shown how a prescription can be written to solve all the problems of pharmaceutical industries. A problem "Minimizing the wastage of Interferon" has been taken to demonstrate the power of Object-oriented Expert System technology.

Ccis Networking - January 1993, Nova University

CCIS Networking / SCIS Networking magazines

No abstract provided.

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.

Development Of A Hypermedia Database For The Elementary Classroom, Jane Pattison Brown

All Graduate Projects

A hypermedia database including selected flora and fauna in Kittitas County, Washington, was developed using HyperCard software for researching information about 400+ species. students had the opportunity to use the database in school libraries and in the author's fifth-grade classroom. The database cards accessed videodisc images where available. On the basis of limited study to date, it appears that when studying the environment, student learning was enhanced by the use of database material created by the author.

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 …

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.

Observation Of The Charmed Baryon C+ And Measurement Of The Isospin Mass Splittings Of The C, Crawford, G.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.

Search For Τ-→Γμ-: A Test Of Lepton Number Conservation, A. Bean, M. Thulasidas

Research Collection School Of Computing and Information Systems

A search for the lepton mumber violating decay of the τ lepton to the γμ final state has been performed with the CLEO II detector at the Cornell e+e− storage ring CESR. In a data sample that corresponds to an integrated luminosity of 1.55 fb−1, we observe no candidates in the signal region. We thus determine an upper limit of B(τ−→γμ−)

A Rule-Based System For Query Feedback, Hock C. Chan, Kwok-Kee Wei, Keng Siau

Research Collection School Of Computing and Information Systems

The authors propose a rule-based system which provides feedback in order to give the user a better understanding of the user's queries. This technique improves query accuracy and confidence. A rule-based expert system that pinpoints syntax errors is described. It suggests possible semantics errors and provides possible solutions, as well as the English translation for the queries. The system can be used for computer-aided training and in actual operations. The system was experimentally tested with a group of students.

Observation Of B0 Decay To Two Charmless Mesons, M. Battle, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

We report results from a search for the decays B0→π+π-, B0→K+π-, and B0→K+K-. We find 90% confidence level upper limits on the branching fractions, Bππ

Tau Decays With One Charged Particle Plus Multiple Π0'S, M. Procario, Manoj Thulasidas

Research Collection School Of Computing and Information Systems

With the CLEO-II detector at the Cornell Electron Storage Ring, we have measured branching fractions for tau lepton decay into one-prong final states with multiple π0’s B0hnπ, normalized to the branching fraction for tau decay into one charged particle and a single π0. We find B0h2π/B0hπ=0.345±0.006±0.016, B0h3π/B0hπ=0.041 ±0.003±0.005, and B0h4π/B0hπ=0.006±0.002±0.002.

Measurement Of Charmless Semileptonic Decays Of B Mesons, Bartelt; J.; Et Al., M. Thulasidas

Research Collection School Of Computing and Information Systems

No abstract provided.

Evidence For Penguin-Diagram Decays: First Observation Of B→K*(892)Γ, R. Ammar, M. Thulasidas

Research Collection School Of Computing and Information Systems

We have observed the decays B0→K*(892)0γ and B−→K*(892)−γ, which are evidence for the quark-level process b→sγ. The average branching fraction is (4.5±1.5±0.9)×10−5. This value is consistent with standard model predictions from electromagnetic penguin diagrams.