An apparatus for delivering ions between vacuum stages. Application to an electronic timepiece. The calculated flow is derived from a process model of the fuel processor and known feed to the fuel processor. By changing the structure of the rollers, the disclosed chain has the advantages of long service life, low operation noise and high driving efficiency. The low-threat response service may also effect presentation of information at a mobile device of the responder directing the responder to the subscriber, information at the mobile device of the subscriber directing the subscriber to the responder, or both.