A semiconductor device including a threshold voltage detector and a boosted voltage generating unit. Use of such a device enables a multi-port digital data communications device such as an ATM network switch to be tested using only one performance test generator while still respecting the statistical multiplexing advantages of the multi-port digital data communications device. Instructions generated by the WTRU in this regard may take the form of simply adjusting one or more timing control values used to dictate deferral, backoff andor other collision avoidance behavior. Flow control is exerted to reduce buffering in the Node B upon degradation of channel qualities, and prior to a High Speed Downlink Shared Channel handover. Each of the steps are repeated at with respect to a different region at least once so as to generate at least one succeeding pose estimation of the vehicle. To this end, in the present invention, a gelatin net is cleaned in a pre-process, the gelatin net is dissolved by a solvent, and a foreign substance is filtered by sequentially using a normal filtering scheme, a microfiltering scheme and an ultrafiltering scheme, a coloring causing material is removed in an ion separating step, and the gelatin net is concentrated and dried.