enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Restrictions on geographic data in China - Wikipedia

    en.wikipedia.org/wiki/Restrictions_on_geographic...

    Article 1 says: This Law is enacted to strengthen the administration of the surveying and mapping undertaking, promote its development and ensure that it renders service to development of the national economy, the building up of national defence, and progress of the society.

  3. Topography - Wikipedia

    en.wikipedia.org/wiki/Topography

    Similar techniques are applied in bathymetric surveys using sonar to determine the terrain of the ocean floor. In recent years, LIDAR (LIght Detection And Ranging), a remote sensing technique that uses a laser instead of radio waves, has increasingly been employed for complex mapping needs such as charting canopies and monitoring glaciers.

  4. Dasymetric map - Wikipedia

    en.wikipedia.org/wiki/Dasymetric_map

    Scrope's 1833 map of world population density, possibly the first dasymetric map. The earliest maps using this kind of approach include an 1833 map of world population density by George Julius Poulett Scrope [4] and an 1838 map of population density in Ireland by Henry Drury Harness, although the methods used to create these maps were never documented.

  5. Surveying - Wikipedia

    en.wikipedia.org/wiki/Surveying

    A surveyor using a total station A student using a theodolite in field. Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial two-dimensional or three-dimensional positions of points and the distances and angles between them.

  6. List of GIS data sources - Wikipedia

    en.wikipedia.org/wiki/List_of_GIS_data_sources

    Only roads between settlements are included, not residential streets, and the dataset is suitable for mapping at the 1:250,000 level. OpenStreetMap: Crowdsourced data for the whole world including most things you'd find on a standard local paper map: points of interest, buildings, roads and road names, ferry routes etc. World Port Index

  7. Geodetic control network - Wikipedia

    en.wikipedia.org/wiki/Geodetic_control_network

    A geodetic control network is a network, often of triangles, that are measured precisely by techniques of control surveying, such as terrestrial surveying or satellite geodesy. It is also known as a geodetic network, reference network, control point network, or simply control network.

  8. Map projection - Wikipedia

    en.wikipedia.org/wiki/Map_projection

    A medieval depiction of the Ecumene (1482, Johannes Schnitzer, engraver), constructed after the coordinates in Ptolemy's Geography and using his second map projection. In cartography, a map projection is any of a broad set of transformations employed to represent the curved two-dimensional surface of a globe on a plane.

  9. Trilateration - Wikipedia

    en.wikipedia.org/wiki/Trilateration

    Two slant ranges from two known locations can be used to locate a third point in a two-dimensional Cartesian space (plane), which is a frequently applied technique (e.g., in surveying). Similarly, two spherical ranges can be used to locate a point on a sphere, which is a fundamental concept of the ancient discipline of celestial navigation ...