A system for reducing signal disturbances in ECG, which disturbances are caused by cardio-pulmonary resuscitation. More specifically, provided are a novel compound 2-nitratoethyl oxirane expressed by formula III, a novel compound poly expressed by formula IV, obtained by polymerization of 2-nitratoethyl oxirane used as a monomer and a preparation method thereof. Substrates 17, 18 are detached from a defective liquid crystal panel, i. A housing body which has a housing upper face is molded around the semiconductor chip andor around the sacrificial layer in a lateral direction parallel to the radiation outlet face. A film of the invention is formed upon a substrate, and includes a nano-columnar structure of a first material and a co-deposited second material. The apparatus is able to receive over a downlink channel of a wireless communication system a first signal having a predetermined bit sequence and second signals having an unknown bit sequence and to determine the quality indicator of the second received signal based on a characteristic of the first received signal.