The present invention provides a process for preparing vinylpyrrolidone polymer powder, which has high bulk density and favorable powder flowability and can be handled with ease. A second plurality of computations are performed on rendered versions of the first and second markup language documents to determine a second plurality of signals, each signal in the second plurality of signals representing a comparison of attributes for the rendered versions of the first and second documents. A microprocessor and memory are provided together with an annunciator which determine whether a slave card annunciator code corresponds to an annunciator code on the master card, thus determining whether a respective student is boarding a bus which corresponds with his respective route. The squitter messages are received while the radio is not communicating on the main channel. Flow calculation circuitry determines flow rate andor composition of the process fluid as a function of the detected microwave signal.