No / This paper investigates into the performance and load management of web servers that are deployed in commercial websites. Such websites offer various services such as flight/hotel booking, online banking, stock trading, and product purchases among others. Customers are increasingly relying on these round-the-clock services which are easier and (generally) cheaper to order. However, such an increasing number of customers' requests makes a greater demand on the web servers. This leads to web servers' overload and the consequential provisioning of inadequate level of service. This paper addresses these issues and proposes an admission control scheme which is based on the class-based priority scheme that classifies customer's requests into different classes. The proposed scheme is formally specified using -calculus and is implemented as a Java-based prototype system. The prototype system is used to simulate the behaviour of commercial website servers and to evaluate their performance in terms of response time, throughput, arrival rate, and the percentage of dropped requests. Experimental results demonstrate that the proposed scheme significantly improves the performance of high priority requests but without causing adverse effects on low priority requests.

Ontology, an explicit specification of a shared conceptualisation, captures knowledge about a specific domain of interest. The realisation of ontologies, revolutionised the way data stored in relational databases is accessed and manipulated through ontology and database integration. When integrating ontologies with relational databases, several choices exist regarding aspects such as database implementation, ontology language features, and mappings. However, it is unclear which aspects are relevant and when they affect specific choices. This imposes difficulties in deciding which choices to make and their implications on ontology and database integration solutions. Within this study, a decision-making tool that guides users when selecting a technology and developing a solution that integrates ontologies with relational databases is developed. A theory analysis is conducted to determine current status of technologies that integrate ontologies with databases. Furthermore, a theoretical study is conducted to determine important features affecting ontology and database integration, ontology language features, and choices that one needs to make given each technology. Based on the building blocks stated above, an artifact-building approach is used to develop the decision-making tool, and this tool is verified through a proof-of-concept to prove the usefulness thereof. Key terms: Ontology, semantics, relational database, ontology and database integration, mapping, Web information portal. / Information Science / M. Sc. (Information Systems)

M. Tech. Business Information Systems / Data underpins the smooth operations and strategic decision-making of the day-to-day operation of an organization’s business processes. With the increasing automation of an organization's activities, large volumes of data are generated faster than they may be consumed and digested. The Department of Rural Development and Land Reform is faced with such a generation of large volumes of data. The department could have benefited from data warehousing in which data is stored within a single repository. However, there is no framework that could inform the adoption of Data Warehousing by a South African government department. This research study therefore intended to design a framework for the adoption of Data Warehousing by a South African government department.

O advento da tecnologia da Internet, juntamente com a World Wide Web, popularizaram e permitiram uma grande expansão e demanda por aplicações web. Por executarem em um ambiete heterogêneo e complexo, as aplicações web apresentam várias características que as diferenciam dos sistemas tradicionais. As particularidades dessas aplicações tornam o fator qualidade essencial para o sucesso dessas aplicações. Alguns requisitos de qualidade, como usabilidade, confiabilidade, interoperabilidade e segurança devem, então, ser validados. Para assegurar a qualidade desejada, são necessárias executar as atividades de Verificação, Validação e Teste (VV&T). Dentre elas, as mais utilizadas são as atividades de teste. Os critérios, estratégias e ferramentas de teste precisam ser identificados e avaliados para se estabelecer uma relação entre os custos e benefícios entre elas, a fim de guiar a escolha de cada uma durante os testes de aplicações web. A realização de estudos experimentais para realizar essa análise beneficia tanto a academia, nas atividades de ensino e pesquisa, como a indústria, nas atividades de seleção e aplicação de critérios, estratégias e ferramentas de teste de aplicações web. Para que os resultados obtidos estejam acessíveis, é proposto o desenvolvimento de um portal de conhecimento que disponibilize de maneira sistemática o conhecimento obtido sobre critérios, estratégias e ferramentas de teste de aplicações web. Esse portal tem como objetivo oferecer às organizações um ambiente compartilhado de conhecimento, a fim de proporcionar a existência de um ciclo de criação, troca, retenção e reuso do conhecimento / The development of internet technology, along with the World Wide Web, made popular and allowed a demand boom and expansion of web applications. Web applications present some characteristics that differentiate them from the traditional systems, since they execute in a heterogeneous and complex environment. The particularities of these applications demand quality as an essential factor for success. Is this way, quality requirements, like usability, reliability, interoperability and security must be validated. To assure the desired quality, it\'s necessary to execute the activities of Verification, Validation and Test (VV&T), where the most used are the testing activities. The testing criteria, strategies and tools need to be identified and evaluated to establish a relation between the costs and benefits, in order to guide the choice of each one during the tests of web applications. The carrying out of experimental studies benefits the academy, in the activities of education and research, and the industry, in the activities of selection and application of criteria, strategies and tools of testing web applications. Moreover, these results need to be accessible to make available information to the interest people. This work presents the development of a knowledge portal, to facilitate knowledge sharing in a systematic way, with information of test criteria, strategies and tools for validating web applications. This portal intends to offer to the organizations and academic institutions a shared environment of web application test knowledge, in order to constitute a knowledge creation, change, retention and reuse cycle

University of Macau / Faculty of Social Sciences and Humanities / Department of English

Thesis (Ph.D.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: leaf 281-310.

Dt. Hochsch. für Verwaltungswiss., Habil.-Schr. 2007--Speyer, 2007.

Thesis (MEd(Computer Integrated Education, Curriculum Studies))--University of Pretoria, 2008. / Includes bibliographical references.

Submitted by PEDRO LUIS BUENO BERTI null (p_berti@hotmail.com) on 2017-12-12T16:49:16Z No. of bitstreams: 1 Dissertação final.pdf: 3486193 bytes, checksum: 51d73640dc4cfc182bbdfa9c7a86778a (MD5) / Submitted by PEDRO LUIS BUENO BERTI null (p_berti@hotmail.com) on 2017-12-14T11:25:02Z No. of bitstreams: 1 Dissertação final.pdf: 3486193 bytes, checksum: 51d73640dc4cfc182bbdfa9c7a86778a (MD5) / Approved for entry into archive by Minervina Teixeira Lopes null (vina_lopes@bauru.unesp.br) on 2017-12-14T13:31:54Z (GMT) No. of bitstreams: 1 berti_plb_me_bauru.pdf: 3486203 bytes, checksum: 72c4491d85beebe056472feffef50669 (MD5) / Made available in DSpace on 2017-12-14T13:31:54Z (GMT). No. of bitstreams: 1 berti_plb_me_bauru.pdf: 3486203 bytes, checksum: 72c4491d85beebe056472feffef50669 (MD5) Previous issue date: 2017-10-30 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / À medida que a internet pode contribuir para revigorar a democracia, a projeção de opiniões e a circulação de ideias sobre gestão pública, portais web que exploram as potencialidades da conversação online têm sido objetos apropriados de pesquisas que buscam conhecer as características da deliberação pública online. Esta dissertação investigou a conversação online em duas iniciativas similares, em países diferentes: VotenaWeb (Brasil) e ISideWith (Estados Unidos), que permitem a expressão de preferências sobre projetos de lei em apreciação no Parlamento. Os dados foram analisados em seis categorias de compreensão: “‘justificação’”, “reciprocidade”, “reflexividade”, “respeito”, “informação” e “tópico”. Os objetivos específicos foram: a) identificar as características da conversação virtual e indicar possíveis condições favoráveis à deliberação; b) fornecer um quadro geral sobre as características da utilização dos dois portais como plataforma para expressão política; c) apontar as possíveis diferenças na exposição de argumentos e uso de fontes de informação pelos usuários. Do portal VotenaWeb foram coletados e analisados, no total, 26.664 comentários, e do portal ISideWith, 3.528 comentários. Os resultados apresentaram diferenças significativas no uso de fontes de informação e no ambiente deliberativo construído pelos usuários. / As far as the internet can contribute to reinvigorate the democracy, the projection of opinions and the circulation of ideas about public administration, web portals that explore potentialities of online conversation have been appropriate subjects of research seeking to understand characteristics of public online deliberation. This dissertation investigated two similar initiatives in different countries: VotenaWeb (Brazil) and ISideWith (United States), which allow expression of preferences concerning bills on appreciation at parliaments. The data were analysed in six categories of comprehension, each one admitting possibilities of classification: “justification”, “reciprocity”, “reflexivity”, “respect”, “information” and “topic”. The specific aims were: a) to identify the virtual conversation characteristics and indicate possible conditions favorable to deliberation present in the each analyzed portal, according to the specialized literature; b) to provide a general framework on the use of the characteristics of the two portals as a platform for political expression; c) to point out possible differences in the expression of opinions and in the use of sources of information by citizens of each country. From VotenaWeb portal 26.664 comments were collected and analysed, and from ISideWith portal 3.528 comments were collected and analysed. The results presented significative differences in the use of sources of information and in the deliberative environment created by users. / 2015/23669-9

Ontology, an explicit specification of a shared conceptualisation, captures knowledge about a specific domain of interest. The realisation of ontologies, revolutionised the way data stored in relational databases is accessed and manipulated through ontology and database integration. When integrating ontologies with relational databases, several choices exist regarding aspects such as database implementation, ontology language features, and mappings. However, it is unclear which aspects are relevant and when they affect specific choices. This imposes difficulties in deciding which choices to make and their implications on ontology and database integration solutions. Within this study, a decision-making tool that guides users when selecting a technology and developing a solution that integrates ontologies with relational databases is developed. A theory analysis is conducted to determine current status of technologies that integrate ontologies with databases. Furthermore, a theoretical study is conducted to determine important features affecting ontology and database integration, ontology language features, and choices that one needs to make given each technology. Based on the building blocks stated above, an artifact-building approach is used to develop the decision-making tool, and this tool is verified through a proof-of-concept to prove the usefulness thereof. Key terms: Ontology, semantics, relational database, ontology and database integration, mapping, Web information portal. / Information Science / M. Sc. (Information Systems)