98 research outputs found

    Service composition based on SIP peer-to-peer networks

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    Today the telecommunication market is faced with the situation that customers are requesting for new telecommunication services, especially value added services. The concept of Next Generation Networks (NGN) seems to be a solution for this, so this concept finds its way into the telecommunication area. These customer expectations have emerged in the context of NGN and the associated migration of the telecommunication networks from traditional circuit-switched towards packet-switched networks. One fundamental aspect of the NGN concept is to outsource the intelligence of services from the switching plane onto separated Service Delivery Platforms using SIP (Session Initiation Protocol) to provide the required signalling functionality. Caused by this migration process towards NGN SIP has appeared as the major signalling protocol for IP (Internet Protocol) based NGN. This will lead in contrast to ISDN (Integrated Services Digital Network) and IN (Intelligent Network) to significantly lower dependences among the network and services and enables to implement new services much easier and faster. In addition, further concepts from the IT (Information Technology) namely SOA (Service-Oriented Architecture) have largely influenced the telecommunication sector forced by amalgamation of IT and telecommunications. The benefit of applying SOA in telecommunication services is the acceleration of service creation and delivery. Main features of the SOA are that services are reusable, discoverable combinable and independently accessible from any location. Integration of those features offers a broader flexibility and efficiency for varying demands on services. This thesis proposes a novel framework for service provisioning and composition in SIP-based peer-to-peer networks applying the principles of SOA. One key contribution of the framework is the approach to enable the provisioning and composition of services which is performed by applying SIP. Based on this, the framework provides a flexible and fast way to request the creation for composite services. Furthermore the framework enables to request and combine multimodal value-added services, which means that they are no longer limited regarding media types such as audio, video and text. The proposed framework has been validated by a prototype implementation

    A graphics software architecture for high-end interactive TV terminals

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    This thesis proposes a graphics architecture for next-generation digital television receivers. The starting assumption is that in the future, a number of multimedia terminals will have access through a number of networks to a variety of content and services. One example of such a device is a media station capable of integrating different kinds of multimedia objects such as 2D/3D graphics and video, reacting to user interaction, and supporting the temporal dimension of applications. Some of the services intended for these devices include, for example, games and enhanced information over broadcasted video. First, this thesis provides an overview of the digital television environment, focusing on the limitations of current receivers and hints at future directions. In addition, this thesis compares different solutions from regional standardisation bodies such as DVB, CableLabs, and ARIB. It proposes the adoption of the most relevant initiative, GEM by DVB. Unfortunately, GEM software middleware only considers Java language as an authoring format, meaning that the declarative environment and advanced functionalities (e.g., 3D graphics support) remain to be standardised. Because in the future different user groups will have different demands with regard to television, this thesis identifies two major extensions to the GEM standard. First, it proposes a declarative environment for GEM that takes into account W3C standardisation efforts. This environment is divided into two configurations: one capable of rendering limited interactive applications such as information services, and another intended for more demanding applications, for example a distance learning portal that synchronises videos of lecturers and slides. Second, this thesis proposes to extend the procedural environment of GEM with 3D graphics support. The potential services of this new profile, High-End Interactive, include games and commercials. Then, based on the requirements the proposed profiles should meet, this thesis defines a graphics architecture model composed of five layers. The hardware abstraction layer is in charge of rendering the final graphics output. The graphical context is a cross-platform abstraction of the rendering region and provides graphics primitives (e.g., rectangles and images). The graphical environment provides the means to control different graphical contexts. The GUI toolkit is a set of ready-made user interface widgets and layout schemes. Finally, high-level languages are easy-to-use tools for developing simple services. The thesis concludes with a report of my experience implementing a digital television receiver based on the proposals described. In addition to testing the application of the proposed graphics architecture to the design and implementation of a next-generation digital television receiver, the implementation permits the analysis of the requirements of such receivers and of the services they can provide.reviewe

    COMPONENT TECHNOLOGIES AND THEIR IMPACT UPON SOFTWARE DEVELOPMENT

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    Software development is beset with problems relating to development productivity, resulting in projects delivered late and over budget. While the term software engineering was first introduced in the late sixties, its current state reflects no other engineering discipline. Component-orientation has been proposed as a technique to address the problems of development productivity and much industrial literature extols the benefits of a component-oriented approach to software development. This research programme assesses the use of component technologies within industrial software development. From this assessment, consideration is given to how organisations can best adopt such techniques. Initial work focuses upon the nature of component-orientation, drawing from the considerable body of industrial literature in the area. Conventional wisdom regarding componentorientation is identified from the review. Academic literature relevant to the research programme focuses upon knowledge regarding the assessment of software technologies and models for the adoption of emergent technologies. The method pays particular attention to literature concerning practitioner focussed research, in particular case studies. The application of the case study method is demonstrated. The study of two industrial software development projects enables an examination of specific propositions related to the effect of using component technologies. Each case study is presented, and the impact of component-orientation is each case is demonstrated. Theories regarding the impact of component technologies upon software development are drawn from case study results. These theories are validated through a survey of practitioners. This enabled further examination of experience in component-based development and also understanding how developers learn about the techniques. A strategy for the transfer of research findings into organisational knowledge focuses upon the packaging of previous experience in the use of component-orientation in such a way that it was usable by other developers. This strategy returns to adoption theories in light of the research findings and identifies a pattern-based approach as the most suitable for the research aims. A pattern language, placed in the context of the research programme, is developed from this strategy. Research demonstrates that component-orientation undoubtedly does affect the development process, and it is necessary to challenge conventional wisdom regarding their use. While component-orientation provides the mechanisms for increased productivity in software development, these benefits cannot be exploited without a sound knowledge base around the domain

    Developing a distributed electronic health-record store for India

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    The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

    Embedded System Design

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    A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues

    Embedded System Design

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    A unique feature of this open access textbook is to provide a comprehensive introduction to the fundamental knowledge in embedded systems, with applications in cyber-physical systems and the Internet of things. It starts with an introduction to the field and a survey of specification models and languages for embedded and cyber-physical systems. It provides a brief overview of hardware devices used for such systems and presents the essentials of system software for embedded systems, including real-time operating systems. The author also discusses evaluation and validation techniques for embedded systems and provides an overview of techniques for mapping applications to execution platforms, including multi-core platforms. Embedded systems have to operate under tight constraints and, hence, the book also contains a selected set of optimization techniques, including software optimization techniques. The book closes with a brief survey on testing. This fourth edition has been updated and revised to reflect new trends and technologies, such as the importance of cyber-physical systems (CPS) and the Internet of things (IoT), the evolution of single-core processors to multi-core processors, and the increased importance of energy efficiency and thermal issues

    Abstractions and Static Analysis for Verifying Reactive Systems

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    Fokkink, W.J. [Promotor]Sidorova, N. [Copromotor

    Component-based control system development for agile manufacturing machine systems

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    It is now a common sense that manufactures including machine suppliers and system integrators of the 21 st century will need to compete on global marketplaces, which are frequently shifting and fragmenting, with new technologies continuously emerging. Future production machines and manufacturing systems need to offer the "agility" required in providing responsiveness to product changes and the ability to reconfigure. The primary aim for this research is to advance studies in machine control system design, in the context of the European project VIR-ENG - "Integrated Design, Simulation and Distributed Control of Agile Modular Machinery"

    A proposal for a formal specification using SDL of an invehicle network based on the FlexRay protocol with automatic Java code generation

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    Orientador: Walter da Cunha BorelliDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoResumo: Este trabalho apresenta uma proposta de especificação formal em SDL de uma rede de comunicação intraveicular baseada no protocolo de comunicação FlexRay com geração automática de código Java. O modelo proposto se baseia naquele apresentado na especificação padrão do protocolo FlexRay, porém algumas contribuições foram feitas a fim de gerar uma rede FlexRay funcional e executável. O modelo SDL gerado confere uma formalização comportamental ao sistema, permitindo a sua validação e a simulação de suas principais funcionalidades e casos críticos através da ferramenta SDL TAU Suite. Depois de o sistema ser modelado, simulado e validado é gerado código Java para execução do sistema criado. Para isso, foi desenvolvida uma ferramenta geradora de código Java que recebe como entrada um arquivo com as especificações em SDL e tem-se como resultado um sistema descrito em Java que faz uso de sockets para comunicação entre os processos.Abstract: This work presents a proposal of formal specification using SDL for an in-vehicle network based on the FlexRay protocol with automatic generation of Java code. The proposed model is based on that presented in the standard specification of the FlexRay protocol, although some contributions were made in order to generate a functional and executable FlexRay network. The SDL model generated provides the system a behavioural formalization, making it possible to validate and simulate its key features and critical cases by the use of the tool TAU SDL Suite. After the system is modeled, simulated and validated is generated Java code for implementing the system created. For this reason it was developed a tool for generating Java code that receives as input a file with the specifications in SDL, and delivers as result a system written in Java that makes use of sockets for communication between processes.MestradoTelecomunicações e TelemáticaMestre em Engenharia Elétric

    Real Time System Development with UML: A Case Study

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    In this thesis we look at the challenges regarding VoIP and to the developer of an application providing this service. We explore CASE tools that can be used to model and verify the design of a VoIP application. VoIP applications will not be accepted by the market unless it is able to provide an audio quality comparable to traditional phones. The voice module of the application that we analyse initially did not meet these requirements. We investigate how the design and implementation must be altered to meet them. Although UML in its current specification is not adapted to the design of real-time applications, CASE tools exist that propose an extension of UML for this purpose. We investigate two of these - Rational Rose RT and Telelogic Tau - for their usefulness in re-engineering the application. We show their support partially covers our needs and we present novel UML concepts that would have been useful in resolving our task. We further demonstrate important new concepts of UML 2.0
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