Service selection is one of the current challenges in Service orientedcomputing (SOC). We propose a service selection method for replacing used services in case of a failure. the approach considers the functional as ...
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Developing fault tolerant ambient systems requires many challenging factors to be considered due to the nature of such systems, which tend to contain a lot of mobile elements that change their behaviour depending on t...
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ISBN:
(纸本)9780769527659
Developing fault tolerant ambient systems requires many challenging factors to be considered due to the nature of such systems, which tend to contain a lot of mobile elements that change their behaviour depending on the surrounding environment, as well as the possibility of their disconnection and re-connection. It is therefore necessary to construct the critical parts of fault tolerant ambient systems in a rigorous manner this can be achieved by deploying formal approach at the design stage, coupled with sound framework and support at the implementation stage. In this paper we briefly describe a middleware that we developed to provide system structuring through the concepts of roles, agents, locations and scopes, making it easier for the developers to achieve fault tolerance. We then outline our experience in developing an ambient lecture system using the combination of formal approach and our middleware.
this paper presents a lightweight CORBA fault-tolerance service called FTS. the service is based on standard portable features of CORBA, and in that respect is fully CORBA compliant, but does not follow the FT-CORBA s...
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ISBN:
(纸本)0769515762
this paper presents a lightweight CORBA fault-tolerance service called FTS. the service is based on standard portable features of CORBA, and in that respect is fully CORBA compliant, but does not follow the FT-CORBA specifications in areas where the authors felt the latter interfered withtheir other design goals. the service feat a res a unique architecture, based on a new type Of(172 object adaptor, called Group object Adaptor (GOA). the service is portable, interoperable, and aims for simplicity and high-performance request processing. Moreover, the service supports network, partitions, some aspects of non-deterministic processing, and mixing ORBs of different vendors in the same fault-tolerance infrastructure. the paper also presents an analysis of the differences between the service design and FT-CORBA, Withthe hope Of stimulating a discussion about future improvements to the FT-CORBA standard.
Cyber-Physical Systems (CPS) provides a smart infrastructure connecting abstract computational artifacts withthe physical world. this paper presents some challenges for developing distributedreal-time Cyber-Physical...
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Conventional cache memories act to bridge the gap in speeds between the processor and main memory. However, typical cache memories do not take into account of the specific characteristics of objects-oriented programs....
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the distributedreal-time services are developing as a new programming paradigm of the distributedobjectcomputing systems. For supporting these services, we construct a new model of a real-timeobject group (RTOG) p...
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Integration of system components is a crucial challenge in the design of embedded real-time systems, as complex non-functional interdependencies may exist. [20] presented a framework, enabling autonomous verification ...
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the paper develops a distributed systems architecture for dependable Internet based online auctions, meeting the requirements of data integrity, responsiveness, fairness and scalability. It is well-known that a tree-b...
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ISBN:
(纸本)0769510892
the paper develops a distributed systems architecture for dependable Internet based online auctions, meeting the requirements of data integrity, responsiveness, fairness and scalability. It is well-known that a tree-based, recursive design approach caters well for scalability requirements. Withthis observation in mind, the paper develops an approach that permits an auction service to be mapped on to globally distributed auction servers. the paper selects a suitable auction model that treats sellers and buyers symmetrically. this symmetry enables a computational node to play at one level of the tree the role of a seller by dealing with a group of potential buyers as well as to play the role of a potential buyer at the next higher level. Such a symmetric auction (also known as a double auction) is used for supporting a standard auction to be carried out in a hierarchic manner. An architecture is developed and basic algorithms and protocols are presented.
Recently, new trends in application development for distributed platforms, such as the composable services model, attempt to provide more flexibility in system design, deployment and execution. Such trends, and partic...
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ISBN:
(纸本)9780769527659
Recently, new trends in application development for distributed platforms, such as the composable services model, attempt to provide more flexibility in system design, deployment and execution. Such trends, and particularly the referred composable services model, can also be beneficial in real-timedistributed embedded systems, also providing a means to support more adaptive behaviors, reacting to the execution environment or coping with system. reconfiguration. this paper explores a relatively new direction, which is the extension of the service-based model to dynamic, i.e. at run-time, composition in real-timedistributed environments, in order to support the level of flexibility and adaptibility referred above. the paper proposes an architecture to support such dynamic service composition that is based on the Flexible time Triggered communication paradigm (FTT). To achieve the desired goal, we also redefine the concepts of service and service-based application in the concept of the FTT paradigm. Finally, we show experimental results obtained with a prototype implementation of the proposed architecture that confirm its feasibility and good temporal behavior
Many real-time systems use preemptive priorities in their internals to guarantee certain real-time performance. this includes technologies that range from RTSJ (the real- time Specification for Java) to middleware lik...
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