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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.
11

On-line tuning of data placement in parallel databases

Achyutuni, Kiran Jyotsna January 1996 (has links)
No description available.
12

AUTONOMIC WORKLOAD MANAGEMENT FOR DATABASE MANAGEMENT SYSTEMS

Zhang, Mingyi 07 May 2014 (has links)
In today’s database server environments, multiple types of workloads, such as on-line transaction processing, business intelligence and administrative utilities, can be present in a system simultaneously. Workloads may have different levels of business importance and distinct performance objectives. When the workloads execute concurrently on a database server, interference may occur and result in the workloads failing to meet the performance objectives and the database server suffering severe performance degradation. To evaluate and classify the existing workload management systems and techniques, we develop a taxonomy of workload management techniques. The taxonomy categorizes workload management techniques into multiple classes and illustrates a workload management process. We propose a general framework for autonomic workload management for database management systems (DBMSs) to dynamically monitor and control the flow of the workloads and help DBMSs achieve the performance objectives without human intervention. Our framework consists of multiple workload management techniques and performance monitor functions, and implements the monitor–analyze–plan–execute loop suggested in autonomic computing principles. When a performance issue arises, our framework provides the ability to dynamically detect the issue and to initiate and coordinate the workload management techniques. To detect severe performance degradation in database systems, we propose the use of indicators. We demonstrate a learning-based approach to identify a set of internal DBMS monitor metrics that best indicate the problem. We illustrate and validate our framework and approaches using a prototype system implemented on top of IBM DB2 Workload Manager. Our prototype system leverages the existing workload management facilities and implements a set of corresponding controllers to adapt to dynamic and mixed workloads while protecting DBMSs against severe performance degradation. / Thesis (Ph.D, Computing) -- Queen's University, 2014-05-07 13:35:42.858
13

Construction and management of large-scale and complex virtual manufacturing environments

Xu, Zhijie January 2000 (has links)
No description available.
14

Uma abordagem lógica para o gerenciamento de identificadores de objetos em sistemas gerenciadores de banco de dados não convencionais /

Ferrizzi, André Cid. January 2010 (has links)
Orientador: Carlos Roberto Valêncio / Banca: Rogéria Cristiane Gratão de Souza / Banca: Marilde Terezinha Prado Santos / Resumo: Os Sistemas Gerenciadores de Banco de Dados Não Convencionais são utilizados por aplicações que necessitam de e ciência no gerenciamento de objetos complexos. Um dos conceitos fundamentais nestes sistemas e o de identidade de objetos, pois em uma base de dados cada objeto possui um identificador unico que e utilizado para acessá-lo e referenciá-lo em relacionamentos com outros objetos. A implementação de identidade pode ser feita com OIDs físicos ou OIDs lógicos. A abordagem física apresenta o problema de fragmentação da base de dados, pois os OIDs são formados diretamente pelos endereções dos objetos. Já a abordagem lógica não tem este problema, e as técnicas são arvore-B, hashing e mapeamento direto. Cada uma destas abordagens apresenta um determinado problema: arvore-B pode ocupar muita mem oria e o tempo de mapeamento possui complexidade logar tmica; em hashing ocorrem colisões pois o conhecimento prévio do tamanho da tabela hash se torna inviável em base de dados, que crescem de maneira imprevisível; e por ultimo, mapeamento direto, que apesar de possuir o menor tempo de mapeamento dentre as três abordagens, não permite a relocação de todas as páginas da base de dados. Uma outra abordagem lógica é utilizada no Núcleo Gerenciador de Dados Multimídia (NUGEM), o qual vem sendo desenvolvido junto ao Grupo de Banco de Dados do IBILCE de São José do Rio Preto com o intuito de gerenciar dados não convencionais. Neste trabalho e proposta uma nova estrutura e funcionalidades para a t ecnica de gerenciamento de OIDs, cuja experimenta cão foi efetivada junto ao NUGEM, caracterizando uma nova abordagem com um menor tempo de manipulação dos OIDs, a qual pode ser nomeada de mapeamento indireto. E tamb em avaliado o esgotamento de OIDs, comprovando-se que este não representa um problema para a abordagem de mapeamento indireto. Em comparaçãocom as abordagens... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Non-Conventional Database Management Systems are used for applications that require e cient management of complex objects. One fundamental concept of these systems is object identity, because in a database each object has a unique identi er that is used to access it and reference it in relationships with another objects. The implementation of identity can be made with physical OIDs or logical OIDs. The physical approach presents the problem of fragmenting the database, because the OIDs are formed directly by addresses of objects. The logical approach does not have this problem, and the techniques are B-tree, hashing and direct mapping. Each of these approaches presents a particular problem: B-tree can occupy a lot of memory and its mapping time is logarithmic, in hashing collisions occur because the prior knowledge of the table size becomes a problem in databases, which grow in unpredictable ways, and nally, direct mapping, which despite having the smallest mapping time of the three approaches, does not allow the relocation of all pages in the database. Another logical approach is used in the Multimedia Data Manager Kernel (NUGEM), which is being developed by the Database Group at IBILCE, S~ao Jos e do Rio Preto, S~ao Paulo, Brazil, in order to manage non-conventional data. This work proposes a new structure and features for the OID management, which was tested in NUGEM, featuring a new approach with a shorter handling time of OIDs, that can be named indirect mapping. It is also evaluated the exhaustion of OIDs, proving that this is not a problem for the indirect mapping approach. Compared with the approaches of the literature, the approach of indirect mapping has constant mapping time, uses less memory than the B-tree approach, has no problems like collisions and, unlike direct mapping, allows total exibility for relocating pages in the database / Mestre
15

Uma abordagem lógica para o gerenciamento de identificadores de objetos em sistemas gerenciadores de banco de dados não convencionais

Ferrizzi, André Cid [UNESP] 21 May 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-21Bitstream added on 2014-06-13T18:39:30Z : No. of bitstreams: 1 ferrizzi_ac_me_sjrp.pdf: 598030 bytes, checksum: 77b6ef0379d56ab11ae68873cafa2f56 (MD5) / Os Sistemas Gerenciadores de Banco de Dados Não Convencionais são utilizados por aplicações que necessitam de e ciência no gerenciamento de objetos complexos. Um dos conceitos fundamentais nestes sistemas e o de identidade de objetos, pois em uma base de dados cada objeto possui um identificador unico que e utilizado para acessá-lo e referenciá-lo em relacionamentos com outros objetos. A implementação de identidade pode ser feita com OIDs físicos ou OIDs lógicos. A abordagem física apresenta o problema de fragmentação da base de dados, pois os OIDs são formados diretamente pelos endereções dos objetos. Já a abordagem lógica não tem este problema, e as técnicas são arvore-B, hashing e mapeamento direto. Cada uma destas abordagens apresenta um determinado problema: arvore-B pode ocupar muita mem oria e o tempo de mapeamento possui complexidade logar tmica; em hashing ocorrem colisões pois o conhecimento prévio do tamanho da tabela hash se torna inviável em base de dados, que crescem de maneira imprevisível; e por ultimo, mapeamento direto, que apesar de possuir o menor tempo de mapeamento dentre as três abordagens, não permite a relocação de todas as páginas da base de dados. Uma outra abordagem lógica é utilizada no Núcleo Gerenciador de Dados Multimídia (NUGEM), o qual vem sendo desenvolvido junto ao Grupo de Banco de Dados do IBILCE de São José do Rio Preto com o intuito de gerenciar dados não convencionais. Neste trabalho e proposta uma nova estrutura e funcionalidades para a t ecnica de gerenciamento de OIDs, cuja experimenta cão foi efetivada junto ao NUGEM, caracterizando uma nova abordagem com um menor tempo de manipulação dos OIDs, a qual pode ser nomeada de mapeamento indireto. E tamb em avaliado o esgotamento de OIDs, comprovando-se que este não representa um problema para a abordagem de mapeamento indireto. Em comparaçãocom as abordagens... / Non-Conventional Database Management Systems are used for applications that require e cient management of complex objects. One fundamental concept of these systems is object identity, because in a database each object has a unique identi er that is used to access it and reference it in relationships with another objects. The implementation of identity can be made with physical OIDs or logical OIDs. The physical approach presents the problem of fragmenting the database, because the OIDs are formed directly by addresses of objects. The logical approach does not have this problem, and the techniques are B-tree, hashing and direct mapping. Each of these approaches presents a particular problem: B-tree can occupy a lot of memory and its mapping time is logarithmic, in hashing collisions occur because the prior knowledge of the table size becomes a problem in databases, which grow in unpredictable ways, and nally, direct mapping, which despite having the smallest mapping time of the three approaches, does not allow the relocation of all pages in the database. Another logical approach is used in the Multimedia Data Manager Kernel (NUGEM), which is being developed by the Database Group at IBILCE, S~ao Jos e do Rio Preto, S~ao Paulo, Brazil, in order to manage non-conventional data. This work proposes a new structure and features for the OID management, which was tested in NUGEM, featuring a new approach with a shorter handling time of OIDs, that can be named indirect mapping. It is also evaluated the exhaustion of OIDs, proving that this is not a problem for the indirect mapping approach. Compared with the approaches of the literature, the approach of indirect mapping has constant mapping time, uses less memory than the B-tree approach, has no problems like collisions and, unlike direct mapping, allows total exibility for relocating pages in the database
16

A comparison of latency for MongoDB and PostgreSQL with a focus on analysis of source code

Lindvall, Josefin, Sturesson, Adam January 2021 (has links)
The purpose of this paper is to clarify the differences in latency between PostgreSQL and MongoDB as a consequence of their differences in software architecture. This has been achieved through benchmarking of Insert, Read and Update operations with the tool “Yahoo! Cloud Serving Benchmark”, and through source code analysis of both database management systems (DBMSs). The overall structure of the architecture has been researched with Big O notation as a tool to examine the complexity of the source code. The result from the benchmarking show that the latency for Insert and Update operations were lower for MongoDB, while the latency for Read was lower for PostgreSQL. The results from the source code analysis show that both DBMSs have a complexity of O(n), but that there are multiple differences in their software architecture affecting latency. The most important difference was the length of the parsing process which was larger for PostgreSQL. The conclusion is that there are significant differences in latency and source code and that room exists for further research in the field. The biggest limitation of the experiment consist of factors such as background processes which affected latency and could not be eliminated, resulting in a low validity.
17

Area Access Control Systems: Zone Management And Personnel Tracking

Natarajan, Bharath 12 July 2005 (has links)
Area access control is defined as the process of mediating requests to enter a physical area through one or more entry points. Area access control database systems are the collections of information required for an access control system to access, query, retrieve and match real time user inputs with persistent data to ensure the integrity of the resources it protects. This thesis presents an object oriented approach to the design and implementation of a centralized area access control database system and focuses on two features, zone management and personnel tracking. Zone management is defined as the process of hierarchically relating a zone to other immediately adjacent zone(s) that a user is required to have prior access to. This feature will automatically generate all zones that a user requires prior access to in order to approach a target zone. To implement zone management, the database system is required to support recursive relationships and recursive querying. The personnel-tracking feature allows the administrator to obtain information such as the movement of persons of interest and their interactions with others in the installation at any particular time. The results of this thesis contribute to the implementation of a sophisticated area access control database system capable of handling multiple installations, and generating the access rules and paths for each new user automatically. In addition, the object oriented area access control database system is able to support unconventional data types such as images and sound which are essential for emerging biometric security systems.
18

Searching without SQL: Re-engineering a database-centric web application with open-source information retrieval software.

Timothy A. Ross 26 November 2008 (has links)
This paper seeks to describe the process by which a database-centric web application was redesigned and rewritten to take advantage of Apache’s Lucene - an open-source information retrieval software library written in the Java programming language. After the implementation of a Lucene-based text index of “semi-structured data”, a college radio station's card catalog application was able to deliver higher-quality search results in significantly less time than it was able to do using just a relational database alone. Additionally, the dramatic improvements in speed and performance even allowed the search results interface to be redesigned and enhanced with an improved pagination system and new features such as faceted search/filtering.
19

Design and Implementation of a Web-based Financial Information System

Justin C Watt 2004 April 1900 (has links)
This paper describes the design and initial implementation of a web-based financial information system, intended to replace a Microsoft Access financial database in support of a federally funded, international health project. This system is being reimplemented for the web in order to provide stakeholders across the country (and potentially around the world) access to the project's financial information.
20

Spatial Decision Support System For Archaeological Application: A Case Study For Kaunos Archaeological Site

Baybas, Gizem 01 February 2013 (has links) (PDF)
Geographically located materials are used by the archaeology to analyze and explain the socio-cultural aspects of ancient life. Thus, Geographical Information Systems (GIS) have started to be used in archaeology for many applications. Although, cooperation of GIS and archaeology is considered as beneficial, it has become insufficient to meet the requirements of archaeologists about excavation study. Therefore, the aim of this thesis is to develop Spatial Decision Support System (SDSS) which includes both the GIS tools and analyses and / analytical modeling capabilities in order to satisfy the needs of archaeologists. Moreover, to develop a specialized system for specific archaeological excavation site is aimed. In this study, Kaunos is selected as a case study area and in order to furnish this aim, firstly, needs of archaeologists working in the excavation study of Kaunos are analyzed. Secondly, GIS tools and analyses are determined which meet the requirements of archaeologists. Finally, SDSS for Kaunos Archaeological Excavation Site is developed. It is composed of four components namely / Database Management, Model Management, Dialog Management and Stakeholder Components. Analyses are conducted under the Model Management Component and results are visualized in Dialog Management Component. Result maps help and assist archaeologists in terms of interpreting and examining the socio-cultural, economical and demographical characteristics of Kaunos.

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