The present invention is directed to methods for flameproofing cellulose fibres and articles containing these fibres. Each acute tip is then applied a leveling process as to form a small flat surface on its top. The electromagnetic driving assembly has a housing with coil and a linear magnetic shaft capable of moving linearly in the housing. In addition, the method includes generating the standard reference die based on results of the combining step. The test sample may be a liquid or gas. Such methods may include performing one or more golf strikes to impart trajectories to one or more golf balls.