摘要：Multiple constraints for schematic road network map cartographic design are analyzed and summarized. Based on this, a set of quantitative criteria are set up and a new road network generalization method including progressive selection and displacement is proposed. Furthermore, topological checking methods for road networks are researched. Based on these constraints, the points in a road network are classified, and a satisfactory and effective schematic map is designed in a con- crete experiment while maintaining topological consistency of the road network between the original and the schematic map

摘要：At Quesang on the Tibetan Plateau we report a series of hand and foot impressions that appear to have been intentionally placed on the surface of a unit of soft *** travertine was deposited by water from a hot spring which is now inactive and as the travertine lithified it preserved the *** the basis of the sizes of the hand and foot traces,we suggest that two track-makers were involved and were likely *** interpret this event as a deliberate artistic act that created a work of parietal *** travertine unit on which the traces were imprinted dates to between~169 and 226 ka *** would make the site the earliest currently known example of parietal art in the world and would also provide the earliest evidence discovered to date for hominins on the High Tibetan Plateau(above 4000 m a.s.l.).This remarkable discovery adds to the body of research that identifies children as some of the earliest artists within the genus Homo.