Retrial queues arise in various applications such as call centers, services, and computer networks. The study of retrial queues is an important research branch of Queueing Theory. Retrial queues are characterized by the feature that customers who cannot receive service upon arrival do not queue but retry to enter the server after some random time. This makes the analysis of retrial queues more difficult than that of corresponding models without retrials. While the latter can be considered the limit of the former as the retrial time tends to infinity, some scaling limits are needed to obtain a scaled version of the number of retrial customers as the retrial time tends to zero, because the num... More >

As many IoT systems deploy machine learning models to implement intelligent functions, the reliability and performance assurance of artificial intelligence and the Internet of Things (AIoT) system is becoming a crucial issue. While reliability of AIoT system outputs can be improved by redundancy using multiple input data, the system involves performance and energy overheads that may be unacceptable in real deployment under limited computing resources. To ensure the performance and energy-efficiency of AIoT systems, this paper proposes the queueing models for multi-input AIoT systems in two different architectures, namely the parallel and the shared architectures, and compares them with respe... More >