A multilayer flow path member of an ultrasonic fluid measurement apparatus and an ultrasonic fluid measurement apparatus capable of enhancing the measurement accuracy of the mean flow velocity are provided. Particular examples of feed streams that may be concentrated are for example the following feed solutions: brines, seawater, drilling mud, waste water, bio-digestate, and the like. The wheeled chassis is adapted for hitched connection to a vehicle. At least one element in the first set represents data for the first picture of at least one respective GOP, with each such first picture having been encoded as a reference I picture. For example, a suspected cancerous breast of a human may be compared to a known healthy breast to detect differences in the vasculature.