A variable capacitor is provided for use with an electronic circuit board including a first terminal portion and a second terminal portion, to be built in a position indicator. The disclosed lens provides a vision correcting area for the correction of a wearer’s refractive error. The resulting segmentation is coerced into a semantic concept graph and based on domain knowledge and a semantic concept hierarchy. The distortion removal loop removes from the amplified signal the detected distortion component that was produced by the amplifier and reduced by the filter. The image server includes CPU for checking the imaging number and the image end flag and for verifying completion of transfer of the tomographic medical images in the image group.