Made available in DSpace on 2014-06-12T15:49:34Z (GMT). No. of bitstreams: 1 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2009 / O processamento de consultas tem sido abordado como um problema central em ambientes dinâmicos e distribuídos. O ponto crítico do processamento, no entanto, é a reformulação da consulta submetida em um ponto origem em termos de um ponto destino, considerando as correspondências existentes entre eles. Abordagens tradicionais, em geral, realizam a reformulação utilizando correspondências de equivalência. Entretanto, nem sempre conceitos de um ponto origem têm correspondentes equivalentes no ponto destino, o que pode gerar uma reformulação vazia e, possivelmente, nenhuma resposta para o usuário. Neste caso, se o usuário considera interessante receber respostas relacionadas, mesmo que não precisas, é melhor gerar uma reformulação adaptada ou enriquecida e, por consequência, respostas aproximadas, do que nenhuma. Dentro deste escopo, o presente trabalho propõe um enfoque baseado em semântica, denominado SemRef, que visa integrar técnicas de enriquecimento e reformulação de consultas de forma a prover usuários com um conjunto de respostas expandidas. Reformulações exatas e enriquecidas são produzidas para permitir alcançar esse conjunto. Para tal, usamos semântica obtida principalmente de um conjunto de correspondências semânticas que estendem as normalmente encontradas na literatura. Exemplos de correspondências não usuais são closeness e disjointness. Além disso, usamos o contexto do usuário, da consulta e do ambiente como meio de favorecer o processo de reformulação e lidar com informações que somente são obtidas dinamicamente. Formalizamos as definições propostas através da Lógica Descritiva ALC e apresentamos o algoritmo que compõe o enfoque proposto, garantindo, através de propriedades aferidas, sua corretude e completude. Desenvolvemos o algoritmo SemRef através de um módulo de submissão e execução de consultas em um Sistema de gerenciamento de dados em ambiente P2P (PDMS). Mostramos exemplos que illustram o funcionamento e as vantagens do trabalho desenvolvido. Por fim, apresentamos a experimentação realizada com os resultados que foram obtidos

abstract: The ease of programmability in Software-Defined Networking (SDN) makes it a great platform for implementation of various initiatives that involve application deployment, dynamic topology changes, and decentralized network management in a multi-tenant data center environment. However, implementing security solutions in such an environment is fraught with policy conflicts and consistency issues with the hardness of this problem being affected by the distribution scheme for the SDN controllers. In this dissertation, a formalism for flow rule conflicts in SDN environments is introduced. This formalism is realized in Brew, a security policy analysis framework implemented on an OpenDaylight SDN controller. Brew has comprehensive conflict detection and resolution modules to ensure that no two flow rules in a distributed SDN-based cloud environment have conflicts at any layer; thereby assuring consistent conflict-free security policy implementation and preventing information leakage. Techniques for global prioritization of flow rules in a decentralized environment are presented, using which all SDN flow rule conflicts are recognized and classified. Strategies for unassisted resolution of these conflicts are also detailed. Alternately, if administrator input is desired to resolve conflicts, a novel visualization scheme is implemented to help the administrators view the conflicts in an aesthetic manner. The correctness, feasibility and scalability of the Brew proof-of-concept prototype is demonstrated. Flow rule conflict avoidance using a buddy address space management technique is studied as an alternate to conflict detection and resolution in highly dynamic cloud systems attempting to implement an SDN-based Moving Target Defense (MTD) countermeasures. / Dissertation/Thesis / Doctoral Dissertation Computer Science 2017

Diante do moderno paradigma de projeto otimizado de grandes sistemas de engenharia, este trabalho apresenta um ambiente de projeto que inclui uma série de inovações que permitem otimizar problemas multidisciplinares utilizando colaboração remota pela Internet. Muitos trabalhos têm sido desenvolvidos nesse sentido, o que motivou uma parceria internacional entre o Departamento de Engenharia Naval da Universidade de São Paulo e a Ecole Centrale de Nantes. O objetivo desta parceria foi unir a experiência brasileira em projetos de sistemas complexos de engenharia com a experiência francesa em otimização multidisciplinar. Sendo este trabalho fruto de uma colaboração internacional, é importante ter em mente a obrigação existente para que a pesquisa desenvolvida atenda a ambas as expectativas. O objetivo é, a um só tempo, viabilizar a integração de subsistemas conhecidos em um ambiente de projeto que permita a otimização multidisciplinar de sistemas complexos de engenharia e desenvolver contribuições pontuais relevantes no uso de superfícies de resposta, projeto distribuído e no desenvolvimento de estratégias de otimização multidisciplinares. O relatório apresentará uma descrição do problema, seguida da revisão bibliográfica sobre os principais assuntos envolvidos na pesquisa. A descrição do trabalho desenvolvido ocupará os dois próximos capítulos. No primeiro, o trabalho é apresentado privilegiando a visão global do sistema e a integração dos diferentes subsistemas desenvolvidos em um enfoque claramente influenciado pela tradicional visão sistêmica da Engenharia Naval. No capítulo seguinte as principais contribuições pontuais desenvolvidas são detalhadas ao estilo Francês. Por fim é apresentada a aplicação deste trabalho em diversos problemas matemáticos e de engenharia. / Facing the modern paradigm of optimized projects of large engineering systems, this research work presents a project environment that includes a series of innovations that allow the optimization of multidisciplinary problems using remote collaboration through the internet. Many research works have been done around this subject, which have motivated an international partnership between the Departamento de Engenharia Naval da Universidade de Sao Paulo and Ecole Centrale de Nantes. The objective of this partnership was mix the Brazilian expertise in design of engineering systems with the French expertise in multidisciplinary optimization. Being the result of an international collaboration, it is important to keep in mind the existing compromise to fulfill both expectations. The objective is altogether to make the integration of known systems viable in a project environment that allows multidisciplinary optimization of complex engineering systems with the creation of focused contributions that are relevant on the use of response surfaces, design collaborative and on the development of strategies of multidisciplinary optimization. The report will present a description of the problem, followed by a bibliographic revision about the main issues involved in the research. The description of the work is covered on the two following chapters. On the first one, the work approaches a global view of the system and the integration of different developed sub-systems under a perspective clearly influenced by the traditional systemic vision of Naval Engineering. On the next chapter, the main punctual contributions are detailed in the French style. Finally, the application of this work is presented in several mathematical and engineering problems.

Highly distributed environments (HDEs) are deployment environments that include powerful and robust machines in addition to resource-constrained and mobile devices such as laptops, personal digital assistants (or PDAs), smart-phones, GPS devices, sensors, etc. Developing software for HDEs is fundamentally different from the software development for central systems and stable distributed systems. This argument is discussed deeply and in-details throughout this dissertation. HDE applications are challenged by two problems: unreliable networks, and heterogeneity of hardware and software. Both challenges need careful handling, where the system must continue functioning and delivering the expected QoS. This dissertation is a direct response to the mentioned challenges of HDEs. The contribution of this dissertation is the cloud component model and its related formal language and tools. This is the general title. However, and to make this contribution clear, we prefer to present it in the following detailed form: (1) We propose a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. (2) To achieve the above mentioned objective, we propose a novel component model called cloud component (CC). (3) In this dissertation we propose a new approach to assemble CCs using systematic methodology that maintains the properties of CC model. (4) Cloud component development process and cloud component based systems development process. (5) Location modeling and advanced localization for HDEs are the pivotal key in our contribution. (6) Formal language to model single CC, CC assembly, CC development process, and CC based systems. (7) We finally present our fully-developed supporting tools: the cloud component management system CCMS, and the Registry utility. To respond to the challenges posed by HDEs, and to maintain expected software quality at the user endpoint, we think we need to pass a ¿paradigm shift¿ from the way software is designed and implemented currently to our new vision that this dissertation is devoted to. This is a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. The contribution in this thesis has several faces as explained above, but still, these faces are cohesive. Each of these faces form a partial contribution, however, this partial contribution does not mean anything if isolated from the overall proposal. Moreover, the merit of the overall proposal can not be grasped by reading one partial contribution. The merit of the proposal is evident only if all parts of this work are cohesively organized. Finally, we claim that our proposal spans the entire software development process for HDEs, from requirements to deployment and runtime management.

Diante do moderno paradigma de projeto otimizado de grandes sistemas de engenharia, este trabalho apresenta um ambiente de projeto que inclui uma série de inovações que permitem otimizar problemas multidisciplinares utilizando colaboração remota pela Internet. Muitos trabalhos têm sido desenvolvidos nesse sentido, o que motivou uma parceria internacional entre o Departamento de Engenharia Naval da Universidade de São Paulo e a Ecole Centrale de Nantes. O objetivo desta parceria foi unir a experiência brasileira em projetos de sistemas complexos de engenharia com a experiência francesa em otimização multidisciplinar. Sendo este trabalho fruto de uma colaboração internacional, é importante ter em mente a obrigação existente para que a pesquisa desenvolvida atenda a ambas as expectativas. O objetivo é, a um só tempo, viabilizar a integração de subsistemas conhecidos em um ambiente de projeto que permita a otimização multidisciplinar de sistemas complexos de engenharia e desenvolver contribuições pontuais relevantes no uso de superfícies de resposta, projeto distribuído e no desenvolvimento de estratégias de otimização multidisciplinares. O relatório apresentará uma descrição do problema, seguida da revisão bibliográfica sobre os principais assuntos envolvidos na pesquisa. A descrição do trabalho desenvolvido ocupará os dois próximos capítulos. No primeiro, o trabalho é apresentado privilegiando a visão global do sistema e a integração dos diferentes subsistemas desenvolvidos em um enfoque claramente influenciado pela tradicional visão sistêmica da Engenharia Naval. No capítulo seguinte as principais contribuições pontuais desenvolvidas são detalhadas ao estilo Francês. Por fim é apresentada a aplicação deste trabalho em diversos problemas matemáticos e de engenharia. / Facing the modern paradigm of optimized projects of large engineering systems, this research work presents a project environment that includes a series of innovations that allow the optimization of multidisciplinary problems using remote collaboration through the internet. Many research works have been done around this subject, which have motivated an international partnership between the Departamento de Engenharia Naval da Universidade de Sao Paulo and Ecole Centrale de Nantes. The objective of this partnership was mix the Brazilian expertise in design of engineering systems with the French expertise in multidisciplinary optimization. Being the result of an international collaboration, it is important to keep in mind the existing compromise to fulfill both expectations. The objective is altogether to make the integration of known systems viable in a project environment that allows multidisciplinary optimization of complex engineering systems with the creation of focused contributions that are relevant on the use of response surfaces, design collaborative and on the development of strategies of multidisciplinary optimization. The report will present a description of the problem, followed by a bibliographic revision about the main issues involved in the research. The description of the work is covered on the two following chapters. On the first one, the work approaches a global view of the system and the integration of different developed sub-systems under a perspective clearly influenced by the traditional systemic vision of Naval Engineering. On the next chapter, the main punctual contributions are detailed in the French style. Finally, the application of this work is presented in several mathematical and engineering problems.

在文件資料庫的查詢處理上，Top-k相似文件查詢主要是協助使用者可以從龐大的文件集合中，檢索出和查詢文件具有高度相關性的文件集合。將資料庫內的文件依據和查詢文件之相似度程度，選擇出相似度最高的前k篇文件回傳給使用者。然而過去集中式資料庫，因其覆蓋性和可擴充性的不足，使得這種排名傾向的文件查詢處理，需耗費大量時間及運算成本。近年來，使用端對端(Peer-to-peer, P2P)架構解決相關的文件檢索問題已成為一種趨勢，但在高度分散式環境下，支援排名傾向的相似文件查詢是困難的，因為缺乏全域資訊和適當的系統協調者。 在本研究中，我們先針對各節點資料庫作分群前處理，並提出一個利用區域切割的作法[1]，將P2P環境劃分成數個子區塊後，建立特徵索引表。因此在查詢處理時，可透過索引表加快挑選出Top-k相似群集的速度，並且確保有適當數量的回傳結果。最後在實驗中，我們提出的方法會與傳統集中式搜尋引擎以及SON-based [1] 做比較，在高度分散式環境下，我們的方法在執行Top-k相似文件查詢時，會比上述兩種作法有較為優異的表現。 / On query processing in a large database, similar top-k documents query is an important mechanism to retrieve the highly correlated document collection with query for users. It ranks documents with a similarity ranking function and reports the k documents with highest similarity. However, the former approach in web searching, i.e., centralized search engines, rises some issues such as lack of coverage and scalability, impact provides rank-based query become a costly operation. Recently, using Peer-to-peer (P2P) architectures to tackle above issues has emerged as a trend of solution, but due to the shortage of global knowledge and some appropriate central coordinators, support rank-based query in highly distributed environment has been difficulty. In this paper, we proposed a framework to solve these problems. First, we performed the local cluster pre-processing on each peer, followed by the zone creation process, forming sub-zones over P2P network, and then constructing the feature index table to improve the performance of selecting similar top-k cluster results. The experiments show that our approach performs similar top-k documents query outperforms than SON-based approach in highly distributed environment.