882 research outputs found

    A programmable architecture for the provision of hybrid services

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    The success of new service provision platforms will largely depend on their ability to blend with existing technologies. The advent of Internet telephony, although impressive, is unlikely to make telephone customers suddenly turn in favor of computers. Rather, customers display increasing interest in services that span multiple networks (especially Internet Protocol-based networks and the telephone and cellular networks) and open new vistas. We refer to these services as hybrid services and propose an architecture for their provision. This architecture allows for programming the service platform elements (i.e., network nodes, gateways, control servers, and terminals) in order to include new service logics. We identify components that can be assembled to build these logics by considering a service as a composition of features such as address translation, security, call control, connectivity, charging and user interaction. Generic service components are derived from the modeling of these features. We assure that our proposal can be implemented even in existing systems in return for slight changes: These systems are required to generate an event when a special service is encountered. The treatment of this event is handled by an object at a Java Service Layer. Java has been chosen for its platform-neutrality feature and its embedded security mechanisms. Using our architecture, we design a hybrid closed user group service

    Real-Time Scheduling Method for Middleware of Industrial Automation Devices

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    In this study, a real-time scheduling algorithm, which supports periodic and sporadic executions with event handling, is proposed for the middleware of industrial automation devices or controllers, such as industrial robots and programmable logic controllers. When sensors and embedded controllers are included in control loops having different control periods, they should transmit their data periodically to the controllers and actuators; otherwise, fatal failure of the system including the devices could occur. The proposed scheduling algorithm manages modules, namely, the thread type (or .so type) and process type (or .exe type), for periodic execution, sporadic execution, and non-real-time execution. The program structures for the thread-type and process-type modules that can make the proposed algorithm manage the modules efficiently are suggested; then, they are applied in periodic and sporadic executions. For sporadic executions, the occurrences of events are first examined to invoke the execution modules corresponding to the events. The proposed scheduling algorithm is implemented using the Xenomai real-time operating system (OS) and Linux, and it is validated through several examples

    Approach to Adapt a Legacy Manufacturing System Into the IoT Paradigm

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    This work has been supported by Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, by Uninova-CTS research unit and by national funds through FCT -Fundação para a Ciência e a Tecnologia within the research unit CTS - Centro de Tecnologia e Sistemas (project UID/EEA/00066/2013). The authors would like to thank all the institutions.Enterprises are adopting the Internet of Things paradigm as a strategy to improve competitiveness. But enterprises also need to rely on their legacy systems, which are of vital importance to them and normally difficult to reconfigure or modify, their mere replacement being usually not affordable. These systems constitute, therefore, barriers to agility and competitiveness, raising the need to develop cost-effective ways for IoT adaptation. An approach for adapting legacy manufacturing systems into the IoT realm is proposed in this research. The methodology is twofold: an adaptation board is firstly designed to provide IoT connectivity, allowing to remotely invoke the “legacy” functionality as services. Then, the board itself can leverage the legacy system by developing additional functionalities inside it, as the update process is usually triggered by the need of new functionality from these systems. An experiment, which consists of adapting to IoT a small distribution line that is controlled by an aged Programmable Logic Controller, is developed to illustrate how straightforward, affordable and cost effective the adaptation approach is, allowing to holistically achieve a new system with more sophisticated functionality.publishersversionpublishe

    Design and Implementation of a Networked Control System

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    Accelerating BLAST Computation on an FPGA-enhanced PC Cluster

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    This paper introduces an FPGA-based scheme to accelerate mpiBLAST, which is a parallel sequence alignment algorithm for computational biology. Recent rapidly growing biological databases for sequence alignment require highthroughput storage and network rather than computing speed. Our scheme utilizes a specialized hardware configured on an FPGA-board which connects flash storage and other FPGAboards directly. The specialized hardware configured on the FPGAs, we call a Data Stream Processing Engine (DSPE), take a role for preprocessing to adjust data for high-performance multi- and many- core processors simultaneously with offloading system-calls for storage access and networking. DSPE along the datapath achieves in-datapath computing which applies operations for data streams passing through the FPGA. Two functions in mpiBLAST are implemented using DSPE to offload operations along the datapath. The first function is database partitioning, which distributes the biological database to multiple computing nodes before commencing the BLAST processes. Using DSPE, we observe a 20-fold improvement in computation time for the database partitioning operation. The second function is an early part of the BLAST process that determines the positions of sequences for more detailed computations. We implement IDP-BLAST (In-datapath BLAST), which annotates positions in data streams from solid-state drives. We show that IDP-BLAST accelerates the computation time of the preprocess of BLAST by a factor of three hundred by offloading heavy operations to the introduced special hardware
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