A brush seal device for sealing a gap of varying dimensions between two parts moving relatively, has a brush formed by a number of thin bristles arranged in a wall-like form, one end secured to one part in parallel with a retaining portion that supports the brush, and a seal portion at the other end facing the other part for sealing the gap. The present invention also provides a manufacturing method for the semiconductor structure. The lower edge has a plurality of anchor points for affixing the lower edge to a seabed below a body of water. The non-linear gain adaptation is performed, for example, when the input voltage is above a threshold input voltage. Thus, the accommodating member and the attracting member are accurately coaxially formed.