A method and system for controlling a drive motor are provided. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. The computing unit is provided with fault locating means locating the aircraft whose TCAS is faulty when in the presence of several intruding aircraft, by examining the observed differences in pairs of values of a same parameter established for each intruding aircraft. one or more low molecular weight compounds having two or more isocyanate reactive groups and a molecular weight of 120 or less wherein the low molecular weight compounds are present as a residue in the isocyanate functional group containing prepolymer, as a component of the isocyanate reactive component or both;D.