56 research outputs found

    XML-based Execution Plan Format (XEP)

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    Execution plan analysis is one of the most common SQL tuning tasks performed by relational database administrators and developers. Currently each database management system (DBMS) provides its own execution plan format, which supports system-specific details for execution plans and contains inherent plan operators. This makes SQL tuning a challenging issue. Firstly, administrators and developers often work with more than one DBMS and thus have to rethink among different plan formats. In addition, the analysis tools of execution plans only support single DBMSs, or they have to implement separate logic to handle each specific plan format of different DBMSs. To address these problems, this paper proposes an XML-based Execution Plan format (XEP), aiming to standardize the representation of execution plans of relational DBMSs. Two approaches are developed for transforming DBMS-specific execution plans into XEP format. They have been successfully evaluated for IBM DB2, Oracle Database and Microsoft SQL

    Annotation and visualization of endogenous retroviral sequences using the Distributed Annotation System (DAS) and eBioX

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    <p>Abstract</p> <p>Background</p> <p>The Distributed Annotation System (DAS) is a widely used network protocol for sharing biological information. The distributed aspects of the protocol enable the use of various reference and annotation servers for connecting biological sequence data to pertinent annotations in order to depict an integrated view of the data for the final user.</p> <p>Results</p> <p>An annotation server has been devised to provide information about the endogenous retroviruses detected and annotated by a specialized <it>in silico </it>tool called RetroTector. We describe the procedure to implement the DAS 1.5 protocol commands necessary for constructing the DAS annotation server. We use our server to exemplify those steps. Data distribution is kept separated from visualization which is carried out by eBioX, an easy to use open source program incorporating multiple bioinformatics utilities. Some well characterized endogenous retroviruses are shown in two different DAS clients. A rapid analysis of areas free from retroviral insertions could be facilitated by our annotations.</p> <p>Conclusion</p> <p>The DAS protocol has shown to be advantageous in the distribution of endogenous retrovirus data. The distributed nature of the protocol is also found to aid in combining annotation and visualization along a genome in order to enhance the understanding of ERV contribution to its evolution. Reference and annotation servers are conjointly used by eBioX to provide visualization of ERV annotations as well as other data sources. Our DAS data source can be found in the central public DAS service repository, <url>http://www.dasregistry.org</url>, or at <url>http://loka.bmc.uu.se/das/sources</url>.</p

    Non-Intrusive Computing

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    Pervasive computing is an important trend today. It concerns devices and services in a smart space that interact with users in a simple, natural, and harmonious way. Many problems in this domain have been studied from different perspectives in various projects. However, one important characteristic of pervasive computing, which is how to make it non-intrusive so that users can focus on their tasks, has received little formal attention. Nowadays, many computing entities including smart devices, and software components, are involved in our daily lives, and users need to deal with them as well as with other people. Besides, people are easy to reach with multiple devices. We believe there should be a systematic way to help users avoid intrusive ones. We propose a model for posing and answering two questions: will an interaction intrude on its receiver if delivered, and given that the interaction is deliverable, how can it be delivered effectively and not too overtly? With this model, the intrusion problem is analyzed and the essential factors are identified. A quantitative approach is used, so that factors have quantitative values for comparison and computation. We also apply context to refine them in order to achieve better results. We then illustrate how to materialize the model and build a system whose design is inspired by the Jabber framework that includes a collection of standards, technologies, and projects for instant messaging. The discussion is at a general level that does not depend on Jabber. However, by choosing Jabber in implementation, we reuse existing software and technologies, and benefit from Jabber/XMPP standardization, its low entry barrier for application developers, and its rich community support. The main contributions of our work are two-fold. First, we propose a model for intrusiveness in pervasive computing. Second, we address the problem at the system level by designing and realizing it. We also make use of standardized instant-messaging technologies, more precisely Jabber, in the system instantiation to reuse existing software, making the system more flexible and extensible

    An online platform for real-time sensor data collection, visualization, and sharing

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    Sharing sensor data between multiple devices and users can be^challenging for naive users, and requires knowledge of programming and use of different communication channels and/or development tools, leading to non uniform solutions. This thesis proposes a system that allows users to access sensors, share sensor data and manage sensors. With this system we intent to manage devices, share sensor data, compare sensor data, and set policies to act based on rules. This thesis presents the design and implementation of the system, as well as three case studies of its use.Universidade da Madeir

    Middleware for Large-scale Distributed Systems

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    Nos últimos anos o aumento exponencial da utilização de dispositivos móveis e serviços disponibilizados na “Cloud” levou a que a forma como os sistemas são desenhados e implementados mudasse, numa perspectiva de tentar alcançar requisitos que até então não eram essenciais. Analisando esta evolução, com o enorme aumento dos dispositivos móveis, como os “smartphones” e “tablets” fez com que o desenho e implementação de sistemas distribuidos fossem ainda mais importantes nesta área, na tentativa de promover sistemas e aplicações que fossem mais flexíveis, robutos, escaláveis e acima de tudo interoperáveis. A menor capacidade de processamento ou armazenamento destes dispositivos tornou essencial o aparecimento e crescimento de tecnologias que prometem solucionar muitos dos problemas identificados. O aparecimento do conceito de Middleware visa solucionar estas lacunas nos sistemas distribuidos mais evoluídos, promovendo uma solução a nível de organização e desenho da arquitetura dos sistemas, ao memo tempo que fornece comunicações extremamente rápidas, seguras e de confiança. Uma arquitetura baseada em Middleware visa dotar os sistemas de um canal de comunicação que fornece uma forte interoperabilidade, escalabilidade, e segurança na troca de mensagens, entre outras vantagens. Nesta tese vários tipos e exemplos de sistemas distribuídos e são descritos e analisados, assim como uma descrição em detalhe de três protocolos (XMPP, AMQP e DDS) de comunicação, sendo dois deles (XMPP e AMQP) utilzados em projecto reais que serão descritos ao longo desta tese. O principal objetivo da escrita desta tese é demonstrar o estudo e o levantamento do estado da arte relativamente ao conceito de Middleware aplicado a sistemas distribuídos de larga escala, provando que a utilização de um Middleware pode facilitar e agilizar o desenho e desenvolvimento de um sistema distribuído e traz enormes vantagens num futuro próximo.Over the last few years the designing and implementation of applications have evolved to a new breed of applications that are used by a huge number of users at the same time and are capable of being executed in up to thousands of machines physically distributed, even geographically, such as the cloud computing systems, the new concept of “big data” and smart cities. The existence of several components of these systems, distributed in independent machines, brings inevitable issues in terms of designing and implementation of those systems in order to achieve flexible, scalable, robust, reliable and interoperable systems. It is extremely important to design and implement systems that can be capable of providing a communication and coordination among all the components of the system. The concept of implementing a Middleware seems to be a great option to solve most of these issues, allowing a system to communicate with other systems in a really fast, robust and secure way. This thesis pretends to demonstrate that the usage of Middleware technologies to ensure the communication in distributed systems brings a huge number of advantages, such as interoperability between systems, robustness regarding the communication layer, scalability and high speed communications

    Automatic Deployment of Services in the Cloud with Aeolus Blender

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    International audienceWe present Aeolus Blender (Blender in the following), a software product for the automatic deployment and configuration of complex service-based, distributed software systems in the " cloud ". By relying on a configuration optimiser and a deployment planner, Blender fully automates the deployment of real-life applications on OpenStack cloud deployments , by exploiting a knowledge base of software services provided by the Mandriva Armonic tool suite. The final deployment is guaranteed to satisfy not only user requirements and relevant software dependencies , but also to be optimal with respect to the number of used virtual machines

    Design and realization of a middleware for mobile task coordination

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    The trend towards interconnection of applications has long been recognized as a key challenge for information systems design. Following this trend, organi- zations have developed and introduced many distributed systems with differ- ent functionalities. Furthermore, computing becomes today increasingly mobile; performances of mobile devices (i.e. PDAs and smartphones) as well as the expansion of high-speed mobile networks allows many tasks to be performed beyond stationary workspaces. The dramatic growth of stand-alone and partly incompatible applications will negatively affect the integration, coordination and communication for entire so- lution. Contemporary solutions focus on stationary systems only; the usage of mobile devices is limited to simple scenarios (i.e. information access). In order to support the seamless integration of mobile devices, future distributed solutions should take services and service meta-information into account (e.g. variation of network bandwidth, battery power, availability, connectivity, reachability, sensors data and locations of services and service providers). In this master thesis we want to analyze how a distributed environment with va- riety of separated (mobile) service providers - implemented with different tech- nologies - can be integrated and coordinated. Finding compromises between performance, comfort and intelligent intercommunication is the main goal of this thesis. Therefore, it is concentrated on the conceptualization and design of a central middleware component that provide the coordination and communication functionalities for stationary and mobile entities. In order to prove some possible communication scenarios, the thesis provides a middleware-based scenario

    Web Syndication in a Multilevel Security Environment

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    In this thesis, we demonstrate the feasibility of a novel multilevel web application that merges the ability to share sensitive information with cutting-edge Web 2.0 communication paradigms: we develop a multilevel web aggregation service, allowing web content at various classifications to be gathered together and browsed. The architecture supports read-down across subscriptions, supports receiving near-real-time delivery of new low web content to high subjects and demonstrates several thoughtful, ergonomic user interfaces relevant in a multilevel security context. The architecture was prototyped and evaluated using the current Monterey Security Architecture (MYSEA) research system.http://archive.org/details/websyndicationin1094538482Civilian, Naval Postgraduate SchoolApproved for public release; distribution is unlimited

    Segurança e privacidade em terminologia de rede

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    Security and Privacy are now at the forefront of modern concerns, and drive a significant part of the debate on digital society. One particular aspect that holds significant bearing in these two topics is the naming of resources in the network, because it directly impacts how networks work, but also affects how security mechanisms are implemented and what are the privacy implications of metadata disclosure. This issue is further exacerbated by interoperability mechanisms that imply this information is increasingly available regardless of the intended scope. This work focuses on the implications of naming with regards to security and privacy in namespaces used in network protocols. In particular on the imple- mentation of solutions that provide additional security through naming policies or increase privacy. To achieve this, different techniques are used to either embed security information in existing namespaces or to minimise privacy ex- posure. The former allows bootstraping secure transport protocols on top of insecure discovery protocols, while the later introduces privacy policies as part of name assignment and resolution. The main vehicle for implementation of these solutions are general purpose protocols and services, however there is a strong parallel with ongoing re- search topics that leverage name resolution systems for interoperability such as the Internet of Things (IoT) and Information Centric Networks (ICN), where these approaches are also applicable.Segurança e Privacidade são dois topicos que marcam a agenda na discus- são sobre a sociedade digital. Um aspecto particularmente subtil nesta dis- cussão é a forma como atribuímos nomes a recursos na rede, uma escolha com consequências práticas no funcionamento dos diferentes protocols de rede, na forma como se implementam diferentes mecanismos de segurança e na privacidade das várias partes envolvidas. Este problema torna-se ainda mais significativo quando se considera que, para promover a interoperabili- dade entre diferentes redes, mecanismos autónomos tornam esta informação acessível em contextos que vão para lá do que era pretendido. Esta tese foca-se nas consequências de diferentes políticas de atribuição de nomes no contexto de diferentes protocols de rede, para efeitos de segurança e privacidade. Com base no estudo deste problema, são propostas soluções que, através de diferentes políticas de atribuição de nomes, permitem introdu- zir mecanismos de segurança adicionais ou mitigar problemas de privacidade em diferentes protocolos. Isto resulta na implementação de mecanismos de segurança sobre protocolos de descoberta inseguros, assim como na intro- dução de mecanismos de atribuiçao e resolução de nomes que se focam na protecçao da privacidade. O principal veículo para a implementação destas soluções é através de ser- viços e protocolos de rede de uso geral. No entanto, a aplicabilidade destas soluções extende-se também a outros tópicos de investigação que recorrem a mecanismos de resolução de nomes para implementar soluções de intero- perabilidade, nomedamente a Internet das Coisas (IoT) e redes centradas na informação (ICN).Programa Doutoral em Informátic

    Cooperative Project Planning in Getting Things GNOME

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    Tato práce pojednává o rozšíření pro aplikaci Getting Things GNOME, které ji umožní používat pro plánování a správu kooperativních projektů. Čtenář je seznámen se základními principy a vybranými metodami plánování a řízení projektů. V rámci této práce byla identifikovaná cílová skupina uživatelů a jejich potřeb, pro které bylo navrhnuto řešení. Práce obsahuje přehled rozšířeného uživatelského rozhraní pomocí náčrtků. Navrhnuté řešení bylo implementováno a otestováno.This work dicusses the extension for Getting Things GNOME which makes it possible to use it for planning and managment of cooperative projects. Reader is introduced to basics of project planning and project management and selected methods. The target audience and their needs for the extension were identified and their solutions were proposed. This work includes a walkthrough the extension of the user interface in the form of wireframes. The proposed extension was implemented and tested.
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