Systems and methods presented herein provide for the testing and reconfiguration of x-ray devices. The retractable cover may be rolled out and opened using a pulley system having pulley cables, pulleys andor rollers. The oxygen generated by the oxygen-generating electrode is available to the catalyst within a membrane system andor the counter electrode, thereby enabling the electrochemical sensors of the preferred embodiments to function even during ischemic conditions. A number of related operations are determined for each one of the classified data elements. The updated data is then compared to the stored measure. This can limit an influence of the congestion state only to the provisional queue.