In order to solve the problem that the service composition in the logistics field has poor tolerance and unreliable service, a model of logistics service fault-tolerant composition for intelligent logistics system of Internet of Things (IoT) based on π-net was built. Firstly, after a brief introdution of IoT intelligent logistics system, a fault-tolerant service composition framework for the system was provided. Then, a model of logistics service fault-tolerant composition for the system based on π-net was built, and the correctness of fault tolerance and fitting degree of the model were analyzed. Finally, the service reliability and the fault-tolerant reliability of the model were tested, and the comparison with Petri-net, QoS (Quality of Service) dynamic prediction, fuzzy Kano model and modified particle swarm optimization methods in the service composition execution time, user satisfaction, reliability and optimal degree were carried out. The results show that the proposed model has high service reliability and fault-tolerant reliability, and has certain advantages in terms of service composition execution time, user satisfaction, reliability and optimal degree.

The reliability of Embedded System Hardware (ESH) is very important, which is directly related to the quality and longevity of the embedded system. To analyze the reliability of ESH, it was studied on the perspective of hardware using Copula function. At first, abstract formalization of the ESH was defined from composition level. Then reliability modeling of each function module of the ESH was given by considering integration of hardware and software, as well as using Copulas function to establish the reliability model of ESH. Finally, the parameters of the proposed reliability model were estimated, and a specific calculation example by using this proposed model was put forward and compared with some other Copulas functions. The result shows that the proposed model using Copula function is effective.

Embedded Real-time Control System (ERCS) is widely used in all kinds of control systems. Its software is different from other common software. Besides to meet the real-time requirements, the software needs to be reliable. At first, abstract formalization for the software of embedded real-time control system was defined. Then, reliability modeling was given for software modules which can not be subdivided, and the reliability modeling for software of embedded real-time control system was also provided by applying Copula function. The reliability of specific system software was calculated by using the model. The results show that the reliability model established with Copula function takes account of the correlation between software modules, therefore the reliability of software modules of embedded real-time control system was improved compared with the independent modules.