In the upstream phase of object-oriented development, we usually model a target system from multiple points of view. A dataflow view has been recognized as one of the most important views in software engineering. We n...
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ISBN:
(纸本)0769523560
In the upstream phase of object-oriented development, we usually model a target system from multiple points of view. A dataflow view has been recognized as one of the most important views in software engineering. We need to relate dataflow models to OO models and check consistency between them as it is still important even if we adopt object-oriented approach. In this paper, we propose a method to analyze dataflows in OO design models withthe model checker Spin after formalizing them.
this paper proposes a framework based on Web Service to organize the corporation nodes on supply chain. We have defined a strategy for aggregating the agents, including the normal agent and the mobile agent, into the ...
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ISBN:
(纸本)0769523560
this paper proposes a framework based on Web Service to organize the corporation nodes on supply chain. We have defined a strategy for aggregating the agents, including the normal agent and the mobile agent, into the Web service architecture and the functionalities for them to control the business conducts. We also devise a UDDI ranking frame based on analysis of supply chain activities. In this frame, Web Service-oriented technologies and protocols are deployed for modeling, managing and executing business-oriented functionalities. We focus on the efficient integration of supply chain as key points to harmonize these technologies. Agent- orientation concepts and technologies are applied to SCM construction and interaction patterns.
In this work we propose and evaluate a framework for efficient and real-time dissemination of dynamic data in distributed simulation virtual environments in a scalable fashion. A peer-to-peer overlay is used to create...
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ISBN:
(纸本)0769523560
In this work we propose and evaluate a framework for efficient and real-time dissemination of dynamic data in distributed simulation virtual environments in a scalable fashion. A peer-to-peer overlay is used to create self-organizing groups of participants. Filters that combine application-level knowledge are utilized to control the message propagations and minimize the end-to-end delays. Our approach enables nodes to trade-off processing overhead for consistency precision. Our simulation results illustrate that our techniques meet the consistency requirements of the participants, while minimizing the data transmissions and the message delays.
this paper presents a memory management solution for distributedreal-time Java. the proposed model is targeted at distributed applications that require to keep their internal state and that consume a bounded memory s...
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ISBN:
(纸本)0769523560
this paper presents a memory management solution for distributedreal-time Java. the proposed model is targeted at distributed applications that require to keep their internal state and that consume a bounded memory size in their operation. the aim is to provide an alternative to the garbage collector for distributedreal-time systems and to avoid the penalties it introduces. the approach is based on the usage of scoped memory defined in the real-time Specification for Java (RTSJ). Our solution introduces constraints in the programming model and in the current distributed Java architecture. However, these are compensated by eliminating the dependency of the garbage collector in the end-to-end invocation and by achieving se cleaning with respect to the memory consumed by remote invocations.
One of the problems with Java for real-time systems is the unpredictable behavior of garbage collection (GC). GC introduces unexpected load and causes widesirable delays for real-time applications. In this paper, we p...
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ISBN:
(纸本)0769523560
One of the problems with Java for real-time systems is the unpredictable behavior of garbage collection (GC). GC introduces unexpected load and causes widesirable delays for real-time applications. In this paper, we propose a technique that reduces and bounds the memory requirements for real-time Java programs. this technique can eliminate or reduce the need for GC and allows for a more predictable execution behavior and efficient utilization of the available memory. A theoretical model is presented and a number of benchmark tests are used to evaluate this technique in PERC, NewMonics' real-time JVM, and Sun's JVM the results show that in some cases GC can be eliminated and an application's execution time decreases and becomes more predictable.
Organic computing is becoming the new vision for the design of complex systems, satisfying human needs for trustworthy systems that behave life-like by adapting autonomously to dynamic changes of the environment, and ...
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ISBN:
(纸本)0769523560
Organic computing is becoming the new vision for the design of complex systems, satisfying human needs for trustworthy systems that behave life-like by adapting autonomously to dynamic changes of the environment, and have self-x properties as postulated for Autonomic computing. Organic computing is a response to the threatening view of being surrounded by interacting and self-organizing systems which may become unmanageable, showing undesired emergent behavior. Major challenges for organic system design arise from the conflicting requirements to have systems that are at the same time robust and adaptive, having sufficient degrees of freedom for showing self-x properties but being open for human intervention and operating with respect to appropriate rules and constraints to prevent the occurrence of undesired emergent behavior.
Dynamic software reconfiguration is a useful tool to adapt and maintain software systems. In most approaches, the system has to be stopped while the reconfiguration is in progress. this is not suitable for real-time s...
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ISBN:
(纸本)0769523560
Dynamic software reconfiguration is a useful tool to adapt and maintain software systems. In most approaches, the system has to be stopped while the reconfiguration is in progress. this is not suitable for real-time systems, even on small-embedded systems. Timing constraints must be met even while the system is reconfiguring. Our approach is based on the realtime middleware OSA+. Our main objective is to be able to reconfigure services during run-time, with a predictable and predefined blackout time (the timethe systems does not react due to the reconfiguration). three different approaches concerning the blocking or non-blocking state of a service are presented. these approaches can be used to realize a tradeoff between the reconfiguration time and the blackout time.
the widespread use of mobile and wireless computing platforms is leading to a growing interest on dependability issues. Several research studies have been conducted on dependability of mobile environments, but none of...
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ISBN:
(纸本)0769523560
the widespread use of mobile and wireless computing platforms is leading to a growing interest on dependability issues. Several research studies have been conducted on dependability of mobile environments, but none of them attempted to identify system bottlenecks and to quantify dependability measures. this paper proposes a distributed automated infrastructure for monitoring and collecting spontaneous failures of the Bluetooth infrastructure, which is nowadays more and more recognized as an enabler for mobile systems. Information sources for failure data are presented, and preliminary experimental results are discussed.
To ensure global serializability, traditional distributed database systems implement both concurrency control and transaction commit protocols. In a distributed database systems, a commit protocol guarantees the unifo...
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ISBN:
(纸本)0769523560
To ensure global serializability, traditional distributed database systems implement both concurrency control and transaction commit protocols. In a distributed database systems, a commit protocol guarantees the uniform commitment of distributed transaction execution. In the last decade, several extensions to the transaction model adopted in traditional database systems have been proposed in order to support the functional and performance requirements of emerging advanced applications such as CAD/CAM, large software design projects and object-oriented databases. Nested transaction models have been shown to play an important role in such applications, however, these models are not yet fully studied. In this paper our contributions in the field of real-time nested transactions are two fold: (i) we propose a hierarchical and flat protocols for real-time nested transactions, called 2PC-RT-NT, and (ii) we implement a lock mechanism, called 2LP-NT-HP, to solve the data conflicts problem between nested transactions.
Code generation from hybrid system models is a promising approach to producing reliable embedded systems. this approach presents new challenges as the precise semantics of the model are hard to capture in the code. A ...
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ISBN:
(纸本)0769523560
Code generation from hybrid system models is a promising approach to producing reliable embedded systems. this approach presents new challenges as the precise semantics of the model are hard to capture in the code. A framework for generating code was introduced for single threaded/processor environments. Here, we extend it by considering code generation for distributed environments. We also define criteria for faithful implementation of the model. To this end, we define faulty and missed transitions. For preventing faulty transitions, we build on the idea of instrumentation we have developed for sound simulation of hybrid systems. Finally, we present sufficient conditions to avoid missed transitions and provide examples.
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