Research On Cloud Service Composition Based On Process Logic

Cloud manufacturing(CMfg)is a new service-oriented networked manufacturing model inspired by the thought of cloud computing and internet of things.It organizes distributed manufacturing resources to fulfill users' demands with high-quality,cheap and real-time lifecycle manufacturing services.In this way,CMfg could improve the resource utilization,reduce manufacturing costs and promote the development of modern manufacturing technologies in the direction of servitization,greenization and intelligentization.Service composition is a key technology to meet users' demands and realize the value-add of manufacturing resources in the environment of CMfg.In order to improve the flexibility and intelligentization during the process of service composition,information models of manufacturing tasks and manufacturing services are presented.Then,the service matching and composition are studied based on related work and mechanical processes.During the service composition,the decomposition of original manufacturing task and the processing sequence of subtasks codetermine the number and the order of service in the compositional cloud service.However,the determinate processing sequence would limit the flexibility and solution space of cloud service composition.To solve the problem,a matrix of process logic is presented to describe the processing requirements.Based on the matrix,a processing sequence test method is put forward to ensure the flexibility of the processing sequence under the processing requirements.Taking into consideration the logistics time and costs,a result chosen model based on time,cost,energy andreliability is established.For the best compositional cloud service under the limitation of process logic,a double-layer ant colony algorithm(double-layer ACO)is designed which is suitable for the service composition process.In the next,simulation test is conducted to verify the effectiveness of the double-layer ACO,and to compare the algorithm's performances under different logistics conditions and process logic.Finally,based on previous theoretical work,a CMfg service platform is developed.Its core processes,database and partial functions are presented.