The Bike Sharing System is a sustainable urban transport solution that consists of a fleet of bikes placed in various stations. Users will be satisfied if they find available bikes at their departure station and free docks at the destination. Despite the regulation operations of the system provider (i.e., redistribution of bikes by truck) deeper modifications (bike fleet size or station capacity) are often necessary to ensure a satisfactory service rate. In this paper, we model a sub-graph of a Bike Sharing System using the closed queuing network with a Repetitive-Service-Random-Destination blocking mechanism. This model is solved using the Maximum Entropy Method. This model faithfully reproduces the system dynamics considering the limited capacity of stations. We analyze the performance, particularly, via an overall performance indicator of the system. The various control and monitoring decisions (fleet-size, capacity of stations, incoming and outgoing flow of bikes) are applied to find out the best performance levels. The results demonstrate that the overall performance is robust enough regarding the fleet size changes but it degrades with the increase of the stations’ capacity. Finally, the arrival and departure flows control is an efficient and powerful operational leverage.

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-In this work, we expose a closed loop production system which have great similarity with the Kanban system as the Work In-Process (WIP) is constant (CONWIP). This system can suppose more than one machine in every stage with a limited capacity buffer. We consider also that there is a preference for a machine usage in each stage. We use a Closed Queueing Network (CQN) with a repetitive blocking mechanism to model this system. In a first place, we derive the routings to machines in the same stage when we have a preference for a machine on another. In a second place, we look for the optimal WIP to keep in this system by exploiting the Maximum Entropy Method (MEM) for the resolution of the CQN. We present some numerical results on a simple two stage production system which holds the same number of batches looping. Interesting perspectives for the development of the presented model are looked over.