A method and apparatus for modifying a reference voltage between refreshes in a memory device are disclosed. Each point data value included in the line data is obtained based upon each pixel value in a pixel array arranged in a Y-axis direction having the same X coordinates in the evaluation area. The boot image is used to harvest an image by determining data on a local disk of the managed endpoint to be included in the image that are not already stored in the image library. The vibration is attributable to a composite mechanical operation of the first and second subassemblies of the equipment.