【摘要】 一种扩展的Pi演算被提出并用来建模使用PSO方法的QoS感知的服务选择问题。首先对Pi演算的语法部分做如下扩展:将通道扩展为带有维数约束和并发约束的束通道;将并行组合扩展为并行链接并将求和扩展为随机选择和代价选择。其次对Pi演算的语义部分进行扩展,主要是代价测度函数和PSO元控制原语的融入。最后,在这个目标语言的基础上,通过多媒体环境下的一个服务组合例子,对基于PSO的离散模式DPSO的QoS感知的服务选择进行了建模和仿真。仿真结果表明,该方法在处理该类问题时具有良好的性能和规模性。更多还原

【Abstract】 An extended Pi-calculus is proposed to model the QoS-aware service selection using PSO(Particle Swarm Optimization).Firstly,the syntactic components are expanded,which include the beam-channel with dimension and concurrency constraints based on channel,paralleling linkage derived from parallel composition and stochastic and cost choice from summation.Secondly,the semantics of the extended Pi-calculus which import the cost measure function and PSO meta-control primitives are illustrated.Finally,based on this target language,the discrete scheme of PSO-DPSO is used to solve a service selection with a real scenario in multimedia conference with the modeling and simulation.The simulation results show that this method can ensure the good performance and scalability.更多还原