A sheet conveying device including: a separating roller; a separating piece; and conveying rollers. The first mask pattern has a first window wider than the selective area and a second mask pattern has a second window and a third window. The thermally conductive structures can be secured in the heat spreader frame by sizing the openings and the thermally conductive structures such that the thermally conductive structures can be secured within the openings without requiring welding or adhesives. The method further includes subjecting candidate user items to similarity processing, where the degree to which the candidate user items are similar to the seed item is determined, and placing user items in a list of items based on user selected preferences for similarity between items in the list and the seed item.