Abstract: A map generation device is provided with an optimal road network information generation section (11) which extracts only arterial roads from the road map data stored in the road map data storage section (10) in accordance with a fixed determination standard and which generates information about a road network composed of the arterial roads as optimal road network information, and an optimal road map data storage section (12) which stores the generated optimal road network information.

Abstract: A map generation device is provided with an optimal road network information generation section (11) which extracts only arterial roads from the road map data stored in the road map data storage section (10) in accordance with a fixed determination standard and which generates information about a road network composed of the arterial roads as optimal road network information, and an optimal road map data storage section (12) which stores the generated optimal road network information.

Abstract: A temperature pattern measuring device for obtaining the surface temperature distribution of an object. The device receives an image of the measured object and two different wavelength components of light emitted from the object. The device performs a two color temperature process for each minute area within a visual field of the image pickup, detecting the temperature at a portion on the surface of the corresponding measured object, thereby obtaining the temperature pattern thereof. The above minute areas can be set by an electrical method using photoelectric conversion means. Also, a supervision unit for the weld zone at an electrically seamed pipe, may employ the temperature pattern measuring unit of the present invention, the supervision unit producing a composite display of the form of the weld zone and the temperature pattern thereof.