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Articles 1 - 14 of 14

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of N-Tier Architecture Applied To Distributed-Database Systems, Alexandre G. Valente Jun 1999

Analysis Of N-Tier Architecture Applied To Distributed-Database Systems, Alexandre G. Valente

Theses and Dissertations

N-tier architecture has been more commonly used as a methodology for developing large database applications. This work evaluates the use of this architecture instead of the classical Client/Server architecture in developing corporate applications based on distributed databases. The comparison between architectures is performed using applications that execute transactions similar to those defined in the Transaction Process Council Type C benchmark (TPC-C). The environment used for development and testing was the AFIT Bimodal Cluster (ABC); a heterogeneous cluster of PCs, running Microsoft Windows NT 4.0 OS. The comparative experimental analysis demonstrated that the N-tier architecture allows more efficient bandwidth utilization between …


Methodology For Integrating The Scenario Databases Of Simulation Systems, Emilia M. Colonese Jun 1999

Methodology For Integrating The Scenario Databases Of Simulation Systems, Emilia M. Colonese

Theses and Dissertations

The use of many different simulation systems by the United States Department of Defense has resulted in many different scenario data representations contained in heterogeneous databases. These heterogeneous databases all represent the same data concept, but have different semantics due to intrinsic variations among the data models. In this research, I describe a unified scenario database to allow interoperability and reuse of the scenario data components while avoiding the problems of data redundancy. Using the object oriented approach, the data and schema of the scenario databases, represented in an object oriented model, are integrated into a global database also represented …


Multiobjective Evolutionary Algorithms: Classifications, Analyses, And New Innovations, David A. Van Veldhuizen Jun 1999

Multiobjective Evolutionary Algorithms: Classifications, Analyses, And New Innovations, David A. Van Veldhuizen

Theses and Dissertations

This research organizes, presents, and analyzes contemporary Multiobjective Evolutionary Algorithm (MOEA) research and associated Multiobjective Optimization Problems (MOPs). Using a consistent MOEA terminology and notation, each cited MOEAs' key factors are presented in tabular form for ease of MOEA identification and selection. A detailed quantitative and qualitative MOEA analysis is presented, providing a basis for conclusions about various MOEA-related issues. The traditional notion of building blocks is extended to the MOP domain in an effort to develop more effective and efficient MOEAs. Additionally, the MOEA community's limited test suites contain various functions whose origins and rationale for use are often …


Porting The Sisal Functional Language To Distributed-Memory Multiprocessors, Jui-Yuan Ku May 1999

Porting The Sisal Functional Language To Distributed-Memory Multiprocessors, Jui-Yuan Ku

Dissertations

Parallel computing is becoming increasingly ubiquitous in recent years. The sizes of application problems continuously increase for solving real-world problems. Distributed-memory multiprocessors have been regarded as a viable architecture of scalable and economical design for building large scale parallel machines. While these parallel machines can provide computational capabilities, programming such large-scale machines is often very difficult due to many practical issues including parallelization, data distribution, workload distribution, and remote memory latency.

This thesis proposes to solve the programmability and performance issues of distributed-memory machines using the Sisal functional language. The programs written in Sisal will be automatically parallelized, scheduled and …


Automatic Document Classification And Extraction System (Adoces), Xuhong Li May 1999

Automatic Document Classification And Extraction System (Adoces), Xuhong Li

Dissertations

Document processing is a critical element of office automation. Document image processing begins from the Optical Character Recognition (OCR) phase with complex processing for document classification and extraction. Document classification is a process that classifies an incoming document into a particular predefined document type. Document extraction is a process that extracts information pertinent to the users from the content of a document and assigns the information as the values of the “logical structure” of the document type. Therefore, after document classification and extraction, a paper document will be represented in its digital form instead of its original image file format, …


A New-Generation Class Of Parallel Architectures And Their Performance Evaluation, Qian Wang May 1999

A New-Generation Class Of Parallel Architectures And Their Performance Evaluation, Qian Wang

Dissertations

The development of computers with hundreds or thousands of processors and capability for very high performance is absolutely essential for many computation problems, such as weather modeling, fluid dynamics, and aerodynamics. Several interconnection networks have been proposed for parallel computers. Nevertheless, the majority of them are plagued by rather poor topological properties that result in large memory latencies for DSM (Distributed Shared-Memory) computers. On the other hand, scalable networks with very good topological properties are often impossible to build because of their prohibitively high VLSI (e.g., wiring) complexity. Such a network is the generalized hypercube (GH). The GH supports full-connectivity …


Applying Neural Networks In Case-Based Reasoning Adaptation For Cost Assessment Of Steel Buldings, Essam Amin Mlotfy Abdrabou May 1999

Applying Neural Networks In Case-Based Reasoning Adaptation For Cost Assessment Of Steel Buldings, Essam Amin Mlotfy Abdrabou

Archived Theses and Dissertations

No abstract provided.


The Dynamics Of Cyberspace: Examining And Modelling Online Social Structure, Brian S. Butler '89 Apr 1999

The Dynamics Of Cyberspace: Examining And Modelling Online Social Structure, Brian S. Butler '89

Doctoral Dissertations

It has been proposed that online social structures represent new forms of organizing which are fundamentally different from traditional social structures. However, while there is a growing body of empirical research that considers behavioral aspects of online activity, research on online social structure structural remains largely anecdotal. This work consists of three papers that combine previous studies of traditional social structures, empirical analysis of longitudinal data from a sample of Internet listservs, and computational modeling to examine the dynamics of social structure development in networked environments.

The first paper (Title: When is a Group not a Group: An Empirical Examination …


Extensible Multi-Agent System For Heterogeneous Database Association Rule Mining And Unification, Christopher G. Marks Mar 1999

Extensible Multi-Agent System For Heterogeneous Database Association Rule Mining And Unification, Christopher G. Marks

Theses and Dissertations

The Probabilities, Expert System, Knowledge, and Inference (PESKI) System uses the data mining of association rules to fill incompleteness in the knowledge of an expert system. The rules are mined from transactional data sources and then incorporated using an existing link to PESKI. One method of providing a system that will easily allow new data sources to be added is using an information gathering agent-based system. This research first develops a methodology for designing and creating a multi-agent system. It then applies this methodology to design a platform independent means of data mining data sources of any format. The use …


Methodology For Application Design Using Information Dissemination And Active Database Technologies, Robert H. Hartz Mar 1999

Methodology For Application Design Using Information Dissemination And Active Database Technologies, Robert H. Hartz

Theses and Dissertations

In dynamic data environments, the large volume of transactions requires flexible control structures to effectively balance the flow of information between producers and consumers. Information dissemination-based systems, using both data push and pull delivery mechanisms, provide a possible scalable solution for data-intensive applications. In this research, a methodology is proposed to capture information dissemination design features in the form of active database rules to effectively control dynamic data applications. As part of this design methodology, information distribution properties are analyzed, data dissemination mechanisms are transformed into an active rule framework, and the desired reactive behavior is achieved through rule customization. …


Incorporating Scene Mosaics As Visual Indexes Into Uav Video Imagery Databases, Timothy I. Page Mar 1999

Incorporating Scene Mosaics As Visual Indexes Into Uav Video Imagery Databases, Timothy I. Page

Theses and Dissertations

The rise of large digital video archives has strengthened the need for more efficient ways of indexing video files an accessing the information contained in them. Reconnaissance platforms, such as the Predator UAV, are contributing thousands of hours of video footage that require analysis, storage, and retrieval. A process is proposed for converting a video stream into a series of mosaic and selected still images that provide complete coverage of the original video. The video mosaic images can be utilized as visual indexes into a video database. In addition, mosaic images contain information from an entire sequence of video frames …


Data Distribution Techniques For Fault Tolerant Colored Two Dimensional Barcode, Rana Farid Mikhail Jan 1999

Data Distribution Techniques For Fault Tolerant Colored Two Dimensional Barcode, Rana Farid Mikhail

Archived Theses and Dissertations

No abstract provided.


Enterprise Business Objects : Design And Implementation Of A Business Object Framework, Kai-Uwe Schafer Jan 1999

Enterprise Business Objects : Design And Implementation Of A Business Object Framework, Kai-Uwe Schafer

Theses

Software components representing business entities like customer or purchase order introduce a new way of Online Transaction Processing to business applications. Collaborating business objects allow to complete whole business processes as a single distributed transaction, instead of dividing it into queued steps, which sometimes even require user intervention. This IS due to the fact that business objects contain both business data and logic and that they incorporate multiple databases from different vendors and different geographic locations in a single transaction.

Business objects cannot be used as stand-alone components, but require a framework of services that manage persistence, concurrent transactions, and …


Electronic Data Interchange : Its Benefits In Trade Activities For Developing Countries, Luis E. Nova [Morel] Jan 1999

Electronic Data Interchange : Its Benefits In Trade Activities For Developing Countries, Luis E. Nova [Morel]

World Maritime University Dissertations

No abstract provided.