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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Missing Data in the Relational Model

Morrissett, Marion 25 April 2013 (has links)
This research provides improved support for missing data in the relational model and relational database systems. There is a need for a systematic method to represent and interpret missing data values in the relational model. A system that processes missing data needs to enable making reasonable decisions when some data values are unknown. The user must be able to understand query results with respect to these decisions. While a number of approaches have been suggested, none have been completely implemented in a relational database system. This research describes a missing data model that works within the relational model, is implemented in MySQL, and was validated by a user feasibility study.
362

Evaluation of potential DSS tool for BDF-HQ manpower and operational equipment resource planning / Evaluation of potential decision support system tool for Bahrain Defense Force HQ manpower and operational equipment resource planning

Alhamdan, Ali M. 06 1900 (has links)
Approved for public release; distribution is unlimited / This thesis explores the Bahrain Defense Force (BDF) needs for a decision support system in the area of analyzing, establishing and maintaining the organizational structures of BDF units. It also identifies the BDF measures that must be taken to qualify a certain unit structure. Subsequently, the thesis designs and develops a specific DSS prototype that can aid BDF decision makers and planners perspectives in this area. Creating this prototype has involved three different layers to be investigated: the data, the models and the user interfaces. The data layer consists of a Microsoft Access database application that houses BDF Units, Manpower, Vehicles, Weapons, Salaries, and Jobs information. The model layer consists of two Microsoft Excel spreadsheets that contain Infantry Battalion and enhanced Armor Battalion HR optimization models. The UI layer consists of user controls, input/output forms, queries, reports, and visualization aids (i.e. charts and pivot tables). These interfaces were developed using MS Access capabilities. Consequently, the BDF-DSS is an integration of database and optimization technology using widely available desktop tools. The general benefits of this DSS are reduced costs for data gathering, computation, and data presentation, and added value resulting from investigating more alternatives, doing more sophisticated analyses of alternatives, using better methods of comparing alternatives, and making quicker and better decisions. / Bahrain Defense Force author. / Major, Bahrain Defense Force
363

Visualization for Verification Driven Learning in Database Studies

Kallem, Aditya 17 December 2010 (has links)
This thesis aims at developing a data visualization tool to enhance database learning based on the Verification Driven Learning (VDL) model. The goal of the VDL model is to present abstract concepts in the contexts of real-world systems to students in the early stages of computer science program. In this project, a personnel/training management system has been turned into a learning platform by adding a number of features for visualization and quizzing. We have implemented various tactics to visualize the data manipulation and data retrieval operations in database, as well as the message contents in data messaging channels. The results of our development have been utilized in eight learning cases illustrating the applications of our visualization tool. Each of these learning cases were made by systematically implanting bugs in a functioning component; the students are assigned to identify the bugs and at the same time to learn the structure of the software system active
364

Spatiotemporal Indexing With the M-Tree

Finigan, John 07 August 2008 (has links)
Modern GIS applications for transportation and defense often require the ability to store the evolving positions of a large number of objects as they are observed in motion, and to support queries on this spatiotemporal data in real time. Because the M-Tree has been proven as an index for spatial network databases, we have selected it to be enhanced as a spatiotemporal index. We present modifications to the tree which allow trajectory reconstruction with fast insert performance and modifications which allow the tree to be built with awareness of the spatial locality of reference in spatiotemporal data.
365

A metadata service for an infrastructure of large scale distributed scientific datasets

Adeleke, Oluwalani Aeoluwa 12 June 2014 (has links)
In this constantly growing information technology driven era, data migration and replication pose a serious bottleneck in the distributed database infrastructure envi- ronment. For large heterogeneous environments with domains such as geospatial sci- ence and high energy physics, where large array of scienti c data are involved, diverse challenges are encountered with respect to dataset identi cation, location services, and e cient retrieval of information. These challenges include locating data sources, identifying e ective transfer route, and replication, just to mention a few. As dis- tributed systems aimed at constant delivery of data to the point of query origination continue to expand in size and functionality, e cient replication and data retrieval systems have subsequently become increasingly important and relevant. One such system is an infrastructure for large scale distributed scienti c data management. Several data management systems have been developed to help manage these fast growing datasets and their metadata. However little work has been done on allowing cross-communication and data-sharing between these di erent dataset management systems in a distributed, heterogeneous environment. This dissertation addresses this problem, focusing particularly on metadata and provenance service associated with it. We present the Virtual Uni ed Metadata architecture to establish communication between remote sites within a distributed heterogeneous environment using a client-server model. The system provides a frame- work that allows heterogeneous metadata services communicate and share metadata and datasets through the implementation of a communication interface. It allows for metadata discovery and dataset identi cation by enabling remote query between heterogeneous metadata repositories. The signi cant contributions of this system include: { the design and implementation of a client/server based remote metadata query system for scienti c datasets within distributed heterogeneous dataset reposito- ries; { Implementation of a caching mechanism for optimizing the system performance; { Analyzing the quality of service with respect to correct dataset identi cation, estimation of migration and replication time frame, and cache performance.
366

Vestígios de peixes em sítios arqueológicos de caçadores-coletores do Rio Grande do Sul, Brasil / Fish remains in hunter-gatherers archaeological sites of Rio Grande do Sul, Brazil

Ricken, Claudio January 2015 (has links)
Foram estudados os restos de peixes de três sítios arqueológicos no estado do Rio Grande do Sul, Brasil. Os sítios RS-S-327 e o RS-C-61 Pilger, estão localizados nas bacias dos rios Sinos e Caí, em abrigos sob-rocha, formados pela erosão dos arenitos da formação Botucatu. Foram identificadas 14 espécies de peixes no sítio arqueológico RS-S-327-Sangão: Bunocephalus sp.; Crenicichla sp.; Geophagus sp.; Hoplias sp.; Hypostomus sp.; Hoplosternum sp.; Microglanis sp.; Oligosarcus sp.; Pimelodus sp.; Prochilodus sp.; Rhamdia sp.; Salminus sp.; Synbranchus sp. No sítio arqueológico RS-C-61- Adelar Pilger 12 espécies de peixes: Crenicichla sp.; Geophagus sp.; Hoplias sp.; Hoplosternum sp.; Hypostomus sp.; Leporinus sp.; Oligosarcus sp.; Pimelodus sp.; Prochilodus sp.; Rhamdia sp.; Salminus sp.; Synbranchus sp., e uma espécie marinha:Carcharinus sp. A presença de espécies que apresentam migração reprodutiva corrobora a hipótese de que esses abrigos sob-rocha, eram ocupados em períodos mais quentes do ano. A maior exploração de espécies de peixes oriundas de ambientes próximos aos sítios aponta para uma atividade de pesca não especializada, feita dentro da área de influência doméstica dos abrigos. A análise dos vestígios do sítio RS-AS-01, Sambaqui Praia do Paraíso, localizado em Arroio do Sal (RS), demonstrou que molusco Mesodesma mactroides, foi a espécie dominante em todos os níveis estratigráficos, sendo seguida por Donax hanleyanus. Dentre os vertebrados, os peixes apresentaram o maior número de peças identificadas, representados em maior número por Genidens sp., Pogonias chromis, Menticirrhuslittoralise Micropogonias furnieri e espécies com menor representação: Paralonchurus brasiliensis, Macrodon sp., Cynoscion sp., Mugil sp., Paralichthys sp., Urophycis sp. e duas espécies dulcícolas: Hoplias sp. e Microglanis sp.. A estimativa das dimensões corporais com base nos otólitos das espécies Genidens sp., Menticirhuslitorallis e Micropogoniasfurnieri, conduziu a hipótese do uso de redes com malha padronizada. As experimentações da quebra e seccionamento de esporões de Genidens barbus, demonstraram que a quebra de esporões "in natura" e dos espécimes assados envoltos em folhas mostraram padrões de quebra irregulares. Os esporões dos exemplares assados em forno elétrico mostraram padrões de quebra regulares. Os exemplares expostos ao cozimento apresentaram um padrão de descoloração diretamente proporcional ao tempo de exposição. Os exemplares seccionados com lasca lítica por fricção apresentaram padrões condizentes com aqueles encontrados em esporões procedentes de sítios arqueológicos da cultura Sambaqui. Tendo como objetivo fornecer opções para melhoria das análises arqueofaunísticas, foi desenvolvido um programa para o gerenciamento de dados zooarqueológicos, utilizando a linguagem Pascal e como compilador/editor o ambiente de programação Delphi. O banco de dados é formado por lotes numerados sequencialmente, onde além das informações básicas para identificação da origem das peças é possível incluir informações sobre taxonomia, anatomia e tafonomia das peças. Considerando a grande diversidade de animais, as opções para inclusão de novos táxons estão em aberto a partir do nível de Filo. Diversas opções oferecidas pela bibliografia para os cálculos de NISP (número de espécimes identificados), NMI (Número mínimo de indivíduos) e tafonomia, foram contempladas pelo programa O sistema desenvolvido possibilita a tradução do software para qualquer língua com alfabeto latino e interação remota entre o usuário remoto e um servidor central. O programa ArchaeoBones, demonstrou ser eficiente para o registro de vestígios arqueológicos, geração de dados primários e secundários com confiabilidade e repetibilidade compatíveis com o grande número de dados utilizados. / Were studied the fish remains of three archaeological sites in the state of Rio Grande do Sul State, Brasil. The RS-S-327 and the RS-C-61, Pilger sites are located in the Sinos and Caí rivers basins in rock shelters formed by erosion of the Botucatu formation sandstones. Were identified 14 species of fish in RS-S-327-Sangão site: Bunocephalus sp.; Crenicichla sp.; Geophagus sp.; Hoplias sp.; Hypostomus sp.; Hoplosternum sp.; Microglanis sp.; Oligosarcus sp.; Pimelodus sp.; Prochilodus sp.; Rhamdia sp.; Salminus sp.; Synbranchus sp. And 12 species of fish in the RS-C-61- Adelar Pilger archaeological site: Crenicichla sp.; Geophagus sp.; Hoplias sp.; Hoplosternum sp.; Hypostomus sp.; Leporinus sp.; Oligosarcus sp.; Pimelodus sp.; Prochilodus sp.; Rhamdia sp.; Salminus sp.; Synbranchus sp., and a marine species: Carcharinus sp. The hypothesis that these rock shelters were occupied in warmer periods of the year is suported by the presence of species with reproductive migration. A further exploration of fish species from environments close to the sites point to a fishing activity unspecialized made within the domestic shelters range of influence.The analysis of the remains of RS-AS-01, Sambaqui Praia do Paraíso site, located in Arroio do Sal (RS) showed that clam Mesodesma mactroides was the dominant species in all stratigraphic levels, followed by Donax hanleyanus. Among vertebrates, the fish had the highest number of identified parts, represented in numbers by Genidens sp.; Pogonias chromis, Menticirrhus littoralis and Micropogonias furnieri and species with less representation: Paralonchurus brasiliensis, Macrodon sp.; Cynoscion sp.; Mugil sp.; Paralichthys sp.; Urophycis sp., and two freshwater species: Hoplias sp. and Microglanis sp. Based on otolith dimensions, the estimation of body size of Genidens sp.; Menticirhus litorallis and Micropogonias furnieri has led the hypothesis of a use of nets with standardized mesh. The experiments of breaking and sectioning demonstrated that in Genidens barbus copies, breaking spines "in natura" and roasted specimens wrapped in leaves showed irregulars break patterns The spines of specimens roasted in an electric oven showed regular breaks paterns. The specimens exposed to cooking in wather, showed a discoloration pattern directly proportional to the exposure time. Spines sectioned by lithic flake friction showed consistent patterns with those found in spines coming from Sambaqui culture archaeological sites. Aiming supply options to improvement of archaeofaunal analyzes, we developed a software for zooarchaeologycal data management, using Pascal language and Delphi programming environment how compiler/editor. The database consists of sequentially numbered lots, in which beyond the basic information to identify the origin of parts, can include information on taxonomy, anatomy and taphonomy of the pieces. Regard to the great diversity of animals, the options to include new taxa are open from Phylum level. Several options offered by bibliography for NISP (number of identified specimens) and MNI (minimum number of individuals) calculations and taphonomic characteristics were included in the program. The developed system allows the software translation into any language in Latin alphabet and interaction between the remote user and a central server. The ArchaeoBones software proved efficient for recording archaeological remains, generating primary and secondary data with consistent reliability and repeatability with the large number of data used.
367

Privacy preserving data publishing. / CUHK electronic theses & dissertations collection

January 2008 (has links)
The advance of information technologies has enabled various organizations (e.g., census agencies, hospitals) to collect large volumes of sensitive personal data (e.g., census data, medical records). Due to the great research value of such data, it is often released for public benefit purposes, which, however, poses a risk to individual privacy. A typical solution to this problem is to anonymize the data before releasing it to the public. In particular, the anonymization should be conducted in a careful manner, such that the published data not only prevents an adversary from inferring sensitive information, but also remains useful for data analysis. / This thesis prevents an extensive study on the anonymization techniques for privacy preserving data publishing. We explore various aspects of the problem (e.g., definitions of privacy, modeling of the adversary, methodologies of anonymization), and devise novel solutions that address several important issues overlooked by previous work. Experiments with real-world data confirm the effectiveness and efficiency of our techniques. / Xiao, Xiaokui. / Adviser: Yufei Yao. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3618. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 307-314). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
368

Enhance DBMS capabilities using semantic data modelling approach.

January 1990 (has links)
by Yip Wai Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 132-135. / ABSTRACT / ACKNOWLEDGEMENTS / PART I / Chapter 1 --- OVERVIEW ON SEMANTIC DATA MODELLING APPROACH … --- p.1 / Chapter 2 --- SCOPE OF RESEARCH --- p.4 / Chapter 3 --- CONCEPTUAL STRUCTURE OF SAM* --- p.7 / Chapter 3.1 --- Concepts and Associations --- p.7 / Chapter 3.1.1 --- Membership Association --- p.8 / Chapter 3.1.2 --- Aggregation Association --- p.8 / Chapter 3.1.3 --- Generalization Association --- p.9 / Chapter 3.1.4 --- Interaction Association --- p.10 / Chapter 3.1.5 --- Composition Association --- p.11 / Chapter 3.1.6 --- Cross-Product Association --- p.12 / Chapter 3.1.7 --- Summary Association --- p.13 / Chapter 3.2 --- An Example --- p.14 / Chapter 3.3 --- Occurrences --- p.15 / PART II / Chapter 4 --- SYSTEM OVERVIEW --- p.17 / Chapter 4.1 --- System Objectives --- p.17 / Chapter 4.1.1 --- Data Level --- p.17 / Chapter 4.1.2 --- Meta-Data Level --- p.18 / Chapter 4.2 --- System Characteristics --- p.19 / Chapter 4.3 --- Design Considerations --- p.20 / Chapter 5 --- IMPLEMENTATION CONSIDERATIONS --- p.23 / Chapter 5.1 --- Introduction --- p.23 / Chapter 5.2 --- Data Definition Language for Schema --- p.24 / Chapter 5.3 --- Construction of Directed Acyclic Graph --- p.27 / Chapter 5.4 --- Query Manipulation Language --- p.28 / Chapter 5.4.1 --- Semantic Manipulation Language --- p.29 / Chapter 5.4.1.1 --- Locate Concepts --- p.30 / Chapter 5.4.1.2 --- Retrieve Information About Concepts --- p.30 / Chapter 5.4.1.3 --- Find a Path Between Two Concepts --- p.31 / Chapter 5.4.2 --- Occurrence Manipulation Language --- p.32 / Chapter 5.5 --- Examples --- p.35 / Chapter 6 --- RESULTS AND DISCUSSIONS --- p.41 / Chapter 6.1 --- Allow Non-Homogeneity of Facts about Entities --- p.41 / Chapter 6.2 --- Field Name is Information --- p.42 / Chapter 6.3 --- Description of Group of Information --- p.43 / Chapter 6.4 --- Explicitly Description of Interaction --- p.43 / Chapter 6.5 --- Information about Entities --- p.44 / Chapter 6.6 --- Automatically Joining Tables --- p.45 / Chapter 6.7 --- Automatically Union Tables --- p.45 / Chapter 6.8 --- Automatically Select Tables --- p.46 / Chapter 6.9 --- Ambiguity --- p.47 / Chapter 6.10 --- Normalization --- p.47 / Chapter 6.11 --- Update --- p.50 / PART III / Chapter 7 --- SCHEMA VERIFICATION --- p.55 / Chapter 7.1 --- Introduction --- p.55 / Chapter 7.2 --- Need of Schema Verification --- p.57 / Chapter 7.3 --- Integrity Constraint Handling Vs Schema Verification --- p.58 / Chapter 8 --- AUTOMATIC THEOREM PROVING --- p.60 / Chapter 8.1 --- Overview --- p.60 / Chapter 8.2 --- A Discussion on Some Automatic Theorem Proving Methods --- p.61 / Chapter 8.2.1 --- Resolution --- p.61 / Chapter 8.2.2 --- Natural Deduction --- p.63 / Chapter 8.2.3 --- Tableau Proof Methods --- p.65 / Chapter 8.2.4 --- Connection Method --- p.67 / Chapter 8.3 --- Comparison of Automatic Theorem Proving Methods --- p.70 / Chapter 8.3.1 --- Proof Procedure --- p.70 / Chapter 8.3.2 --- Overhead --- p.70 / Chapter 8.3.3 --- Unification --- p.71 / Chapter 8.3.4 --- Heuristics --- p.72 / Chapter 8.3.5 --- Getting Lost --- p.73 / Chapter 8.4 --- The Choice of Tool for Schema Verification --- p.73 / Chapter 9 --- IMPROVEMENT OF CONNECTION METHOD --- p.77 / Chapter 9.1 --- Motivation of Improving Connection Method --- p.77 / Chapter 9.2 --- Redundancy Handled by the Original Algorithm --- p.78 / Chapter 9.3 --- Design Philosophy of the Improved Version --- p.82 / Chapter 9.4 --- Primary Connection Method Algorithm --- p.83 / Chapter 9.5 --- AND/OR Connection Graph --- p.89 / Chapter 9.6 --- Graph Traversal Procedure --- p.91 / Chapter 9.7 --- Elimination Redundancy Using AND/OR Connection Graph --- p.94 / Chapter 9.8 --- Further Improvement on Graph Traversal --- p.96 / Chapter 9.9 --- Comparison with Original Connection Method Algorithm --- p.97 / Chapter 9.10 --- Application of Connection Method to Schema Verification --- p.98 / Chapter 9.10.1 --- Express Constraint in Well Formed Formula --- p.98 / Chapter 9.10.2 --- Convert Formula into Negation Normal Form --- p.101 / Chapter 9.10.3 --- Verification --- p.101 / PART IV / Chapter 10 --- FURTHER DEVELOPMENT --- p.103 / Chapter 10.1 --- Intelligent Front-End --- p.103 / Chapter 10.2 --- On Connection Method --- p.104 / Chapter 10.3 --- Many-Sorted Calculus --- p.104 / Chapter 11 --- CONCLUSION --- p.107 / APPENDICES / Chapter A --- COMPARISON OF SEMANTIC DATA MODELS --- p.110 / Chapter B --- CONSTRUCTION OP OCCURRENCES --- p.111 / Chapter C --- SYNTAX OF DDL FOR THE SCHEMA --- p.113 / Chapter D --- SYNTAX OF SEMANTIC MANIPULATION LANGUAGE --- p.116 / Chapter E --- TESTING SCHEMA FOR FUND INVESTMENT DBMS --- p.118 / Chapter F --- TESTING SCHEMA FOR STOCK INVESTMENT DBMS --- p.121 / Chapter G --- CONNECTION METHOD --- p.124 / Chapter H --- COMPARISON BETWEEN RESOLUTION AND CONNECTION METHOD --- p.128 / REFERENCES --- p.132
369

Computer-aided relational database design system.

January 1989 (has links)
Jessie Ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 98-101.
370

Resolving horizontal partitioning and schematic variances using metadatabase approach.

January 2000 (has links)
by Poon, Koon-hei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 80-83). / Abstracts in English and Chinese. / Chapter CHAPTER 1 --- INTRODUCTION --- p.6 / Chapter CHAPTER 2 --- LITERATURE REVIEW --- p.13 / Chapter 2.1. --- BACKGROUND --- p.13 / Chapter 2.2. --- example systems --- p.20 / Chapter 2.2.1 --- Multibase --- p.20 / Chapter 2.2.2. --- Mermai d --- p.23 / Chapter 2.2.3. --- The Metadatabase Approach --- p.26 / Chapter 2.3. --- SUMMARY --- p.29 / Chapter CHAPTER 3 --- THE METADATABASE APPROACH --- p.31 / Chapter 3.1. --- Two-Stage Entity Relationship (TSER) model --- p.31 / Chapter 3.2. --- The GIRD --- p.34 / Chapter 3.3. --- The Metadatabase system in action --- p.36 / Chapter 3.3. --- global query formulations and processing in the metadatabase system --- p.37 / Chapter CHAPTER 4 --- PROBLEM OUTLINES FOR HORIZONTAL PARTITIONING AND ITS VARIANTS --- p.39 / Chapter 4.1. --- Horizontal partitioning --- p.39 / Chapter 4.2. --- Level of abstraction --- p.41 / Chapter 4.3. --- Schematic variances --- p.42 / Chapter 4.4. --- Summary --- p.43 / Chapter 4.5. --- The Scenario --- p.44 / Chapter 4.6. --- Populating the Metadatabase --- p.48 / Chapter CHAPTER 5 --- THE ENHANCEMENTS FOR GLOBAL QUERY WITH HORIZONTAL PARTITIONED DATA OBJECTS --- p.51 / Chapter 5.1. --- Identifying partitioned data objects --- p.51 / Chapter 5.2. --- Additional metadata for the horizontal partitioned data objects --- p.52 / Chapter 5.3. --- Complications of horizontal partitioning problem --- p.54 / Chapter 5.3.1. --- Level of abstraction --- p.55 / Chapter 5.3.2. --- Schematic variances --- p.57 / Chapter 5.4. --- Global query with horizontal partitioning data objects --- p.59 / Chapter 5.5. --- Housing the new metadata --- p.68 / Chapter 5.6. --- Example --- p.72 / Chapter CHAPTER 6 --- ANALYSIS --- p.75 / Chapter CHAPTER 7 --- CONCLUSION AND FUTURE WORKS --- p.78 / REFERENCES --- p.80 / APPENDICES --- p.84 / Chapter A. --- GIRD Definitions --- p.84 / Chapter A1. --- GIRD Model --- p.84 / Chapter A2. --- GIRD/SER Contents --- p.84 / Chapter A3. --- GIRD/OER Constructs --- p.87 / Chapter A4. --- Definition of Meta-attributes --- p.89 / Chapter B. --- Problems Representations in Relation Algebra --- p.96 / Chapter B1. --- Horizontal problem --- p.96 / Chapter B2. --- Level of abstraction --- p.96 / Chapter B3. --- Schematic Variance --- p.97 / Chapter C. --- Details of local systems --- p.98

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