An electrochemical fuel cell stack includes a plurality of fuel cells. The DTV receiver adds, to the standardized hostname, a name for a particular service provider and sends, to a data server, a request for channel map information, where the request is based on the standardized hostname, the name for the particular service provider, and the standardized filename. A set of precoder coefficients can vary with each tone used by each user and depend upon the encoding order of users selected for each tone. A detector is positioned to detect light emanating from at least one object in the flow path, the object having a width along the y-axis, a thickness along the z-axis, and a length along the x-axis. This allows portable languages, such as Java, to be used for secure embedded multiprocessor environments. The techniques have the advantage of minimizing or eliminating external inputs that can introduce inaccuracies.