16,021 research outputs found

    Multi-criteria content adaptation service selection broker

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    In this paper, we propose a service-oriented content adaptation framework and an approach to the Content Adaptation Service Selection (CASS) problem. In particular, the problem is how to assign adaptation tasks (e.g., transcoding, video summarization, etc) together with respective content segments to appropriate adaptation services. Current systems tend to be mostly centralized suffering from single point failures. The proposed algorithm consists of a greedy and single objective assignment function that is constructed on top of an adaptation path tree. The performance of the proposed service selection framework is studied in terms of efficiency of service selection execution under various conditions. The results indicate that the proposed policy performs substantially better than the baseline approach.<br /

    Preliminary specification and design documentation for software components to achieve catallaxy in computational systems

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    This Report is about the preliminary specifications and design documentation for software components to achieve Catallaxy in computational systems. -- Die Arbeit beschreibt die Spezifikation und das Design von Softwarekomponenten, um das Konzept der Katallaxie in Grid Systemen umzusetzen. Eine Einführung ordnet das Konzept der Katallaxie in bestehende Grid Taxonomien ein und stellt grundlegende Komponenten vor. Anschließend werden diese Komponenten auf ihre Anwendbarkeit in bestehenden Application Layer Netzwerken untersucht.Grid Computing

    A scalability analysis of grid allocation mechanisms

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    This article examines the broker's behavior with regard to a varying number of participating nodes and shows that incremental losses have to be accepted in central resource allocation when introducing new nodes. --Grid Computing

    The crowd as a cameraman : on-stage display of crowdsourced mobile video at large-scale events

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    Recording videos with smartphones at large-scale events such as concerts and festivals is very common nowadays. These videos register the atmosphere of the event as it is experienced by the crowd and offer a perspective that is hard to capture by the professional cameras installed throughout the venue. In this article, we present a framework to collect videos from smartphones in the public and blend these into a mosaic that can be readily mixed with professional camera footage and shown on displays during the event. The video upload is prioritized by matching requests of the event director with video metadata, while taking into account the available wireless network capacity. The proposed framework's main novelty is its scalability, supporting the real-time transmission, processing and display of videos recorded by hundreds of simultaneous users in ultra-dense Wi-Fi environments, as well as its proven integration in commercial production environments. The framework has been extensively validated in a controlled lab setting with up to 1 000 clients as well as in a field trial where 1 183 videos were collected from 135 participants recruited from an audience of 8 050 people. 90 % of those videos were uploaded within 6.8 minutes

    Proof-of-Concept Application - Annual Report Year 1

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    In this document the Cat-COVITE Application for use in the CATNETS Project is introduced and motivated. Furthermore an introduction to the catallactic middleware and Web Services Agreement (WS-Agreement) concepts is given as a basis for the future work. Requirements for the application of Cat-COVITE with in catallactic systems are analysed. Finally the integration of the Cat-COVITE application and the catallactic middleware is described. --Grid Computing

    An architecture for user preference-based IoT service selection in cloud computing using mobile devices for smart campus

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    The Internet of things refers to the set of objects that have identities and virtual personalities operating in smart spaces using intelligent interfaces to connect and communicate within social environments and user context. Interconnected devices communicating to each other or to other machines on the network have increased the number of services. The concepts of discovery, brokerage, selection and reliability are important in dynamic environments. These concepts have emerged as an important field distinguished from conventional distributed computing by its focus on large-scale resource sharing, delivery and innovative applications. The usage of Internet of Things technology across different service provisioning environments has increased the challenges associated with service selection and discovery. Although a set of terms can be used to express requirements for the desired service, a more detailed and specific user interface would make it easy for the users to express their requirements using high-level constructs. In order to address the challenge of service selection and discovery, we developed an architecture that enables a representation of user preferences and manipulates relevant descriptions of available services. To ensure that the key components of the architecture work, algorithms (content-based and collaborative filtering) derived from the architecture were proposed. The architecture was tested by selecting services using content-based as well as collaborative algorithms. The performances of the algorithms were evaluated using response time. Their effectiveness was evaluated using recall and precision. The results showed that the content-based recommender system is more effective than the collaborative filtering recommender system. Furthermore, the results showed that the content-based technique is more time-efficient than the collaborative filtering technique

    Fuzzy model reference adaptive controller for position control of a DC linear actuator motor in a robotic vehicle driver

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    This paper presents the controller development for DC linear actuator motors that are used to control the throttle and brake pedals of a passenger car with automatic transmission. The Fuzzy Model Reference Adaptive Control (Fuzzy MRAC) system allows the vehicle to follow speed vs. time profiles of driving cycles by dynamically adjusting the position of the driver pedals in a vehicle. The designed controller was implemented to a virtual vehicle model to determine the required position of the linear pedal actuators over a standard driving cycle. The driving- cycle simulation was conducted using Matlab Simulink and the performance of the controller was analyzed based on overshoot, rise time, settling time and mean square error whereas the robustness test was carried out via set-point tracking method. The result shows 19.79 s rise time, 0.1619% overshoot, 32.65 s settling time and 0.0041 mean square error. The results have proven Fuzzy MRAC to be a viable option for use in highly dynamic systems such as automotive standard driving cycle controllers

    Community resilience frameworks for building disaster resilient community in Malaysia

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    Disasters cannot be prevented fully but their impacts and severity can be lessened through the application of certain frameworks. However, there is currently a lack of a robust framework in building the disaster resilient and sustainable communities in Malaysia. Malaysians are increasingly finding themselves not being spared from disasters especially flood events. In order to keep pace with these occurring disasters in Malaysia, Community Resilience Frameworks are the backbone strategies among various stakeholders and can assure non-futile efforts for building safer and more resilient communities. Community Resilience Framework sets out the drivers, existing good practices, scopes, aims and work streams respectively for a long-term programme designed to increase the disaster resilience of communities. This paper has attempted to review the existence of disaster resilient communities in detail. Some Community Resilience Frameworks in the context of natural disasters in Malaysia will also be discussed. In this paper, literature is used as a foundation for a new insight contribution. A document analysis method on relevant policies and literatures also been adopted. It is envisaged that the findings of this study could be clinically useful for building a disaster resilient community and also closing the gaps in disaster risk reduction (DRR) in Malaysi
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