A polymer comprising recurring units of formula and having a Mw of 1,000-500,000 is provided. The method, adopted by a wireless communication device, includes: searching for a plurality of signal-source types; in response to the searching, determining whether a first type of signal source is available; setting a search configuration based on availability of the first type of signal source; and searching again for the plurality of signal-source types according to the search configuration. Representations of the plurality of media assets are generated. The shield layer is in direct contact with the conductive particles. The section of each electrically-conductive patterns other than the solder-disposed section and a section on which the electronic component is mounted is internally formed in the block. The carriage includes a non-destructive inspection probe such as a meandering wave magnetometer probe or eddy current probe mounted on a slider, so that the probe may be moved along a radial axis, skew axis, axial axis, and rotation axis.