{
  "$type": "site.standard.document",
  "description": "Automotive navigation map data has a multilevel structure in which links have a relationship of association with one another among the minutest level and upper levels that are different from the minutest level in scale. A lowermost-level translation unit 13 uses as original data items old and new…",
  "path": "/patents/972947",
  "publishedAt": "2014-07-02T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "G01C21/26",
    "HITACHI LTD [JP]"
  ],
  "textContent": "Automotive navigation map data has a multilevel structure in which links have a relationship of association with one another among the minutest level and upper levels that are different from the minutest level in scale. A lowermost-level translation unit 13 uses as original data items old and new RDB-form map data items of the minutest level to produce RDB-form difference data of the minutest level. An upper-level difference translation unit 14 produces CSV-format data of a difference of each of the levels of the multilevel structure on the basis of CSV-format data, into which the difference data of the minutest level is translated, and information on the relationship of association among the links of the upper and lower levels in the automotive navigation map data, and integrates the difference data items as final map difference data for an automotive navigation map.",
  "title": "Map distribution server for automotive navigation systems, map data distribution system, and road difference data production method"
}