GIS Representation Method (Exam 12 may, 2014)

Represents discrete objects using coordinates (x, y) to define points, lines, and polygons. Each feature has associated attributes.

A single location in space, represented by a pair of coordinates (x, y), like a tree or a building.

A series of connected points representing a path, such as a road or a stream.

A closed shape representing an area, like a lake or a field.

Represents continuous data using grid cells. Each cell holds a value describing a feature, like elevation or temperature.

A real-world location linked to a point or area on a map.

Data associated with geographic features, stored in a table, such as color, street name or tree type.

The relationships between features, like adjacency (features touching) or containment in vector data.

Raster data can efficiently represent continuous surfaces like temperature or elevation because each cell represents a value at a specific location.

Raster data cannot directly represent spatial relationships like adjacency or containment, which are essential for network analysis or connectivity analysis.

Vector data precisely defines the shape and location of geographic features using points, lines, and polygons, allowing accurate measurements and analysis.

Vector data struggles to represent continuous phenomena like elevation or rainfall, which vary smoothly across space.

The challenge in GIS is to represent the vast amount of geographic information in a way that computers can efficiently manage and analyze - it's about simplifying the real world for digital representation.

Raster systems solve the GIS problem by using a grid of cells, where each cell represents a value, thereby reducing the amount of information needed to represent reality.

Vector systems solve the problem by simplifying geographic features using points, lines, and polygons with minimum information about their shape.

A local ellipsoid is a reference surface for a specific region, adjusted to fit the Earth's geoid better than the global WGS84 ellipsoid.

A process that removes geometric distortions from aerial photographs or satellite imagery, resulting in a geometrically corrected image where all points are at their true geographic positions.

A sensor that emits its own energy source (e.g., radar, lidar) to collect information about a target. It measures the reflected or emitted energy from the target.

A sensor that detects and measures natural energy sources like sunlight or heat (e.g., camera, thermal camera).

Essential components that make up a map's structure and convey information. These typically include a title, legend, scale bar, projection, data source, north arrow, grid, author, date, and inset map.

A map that adheres to strict cartographic principles, providing precise spatial information with accurate representation of geographic features and data.

A visual representation that resembles a map but doesn't follow strict cartographic standards, focusing on conveying a specific message or idea through visual relationships.

A type of map designed to show the distribution of a specific theme or phenomenon, such as population density, temperature, or rainfall.

A map that provides general geographic information about an area, primarily focusing on portraying features like roads, landmarks, and boundaries.