GPS and Digitizers

12 Questions

What is the primary function of the Global Positioning System (GPS)?

To determine a place's exact location

What is the main purpose of digitizers?

To convert analogue or paper images into digital formats

What is an advantage of digital representation of geographic data over paper maps?

High-speed transmission and storage density

What type of geographic data refers to features linked to a single location in space?

Point data

What is the description of a feature's location using a string of spatial coordinates?

Line data

What is a model of the real world, consisting of points, lines, and areas, each defined by its location and attributes?

A map

What type of data model uses vectors to represent geographic features?

Vector data models

What is the function of nodes in vector data models?

To terminate a string of vertices

What determines the size of cells in raster data models?

Data accuracy and resolution

What has led to the development of more sophisticated mapping systems?

Advancements in Geographic Information Systems (GIS)

What is an essential component of GIS?

Hardware

What type of data is crucial for ensuring accurate location of geographic features in GIS?

Geographic data

Study Notes

Geographic Data and Representation

Area data, also known as polygons, describes features like forest stands, soil classification areas, administrative boundaries, and climate zones.

Spatial Data Models

There are three types of spatial data models: vector, raster, and image.
Vector data models use vectors to represent geographic features.
Raster data models use a grid-cell data structure, dividing geographic areas into cells.
Image data models use landscape photographs.

Vector Data Models

Vector data models define geographic features using sequential points or vertices.
Point features are defined by one coordinate pair.
Vector lines, or arcs, consist of a string of vertices terminated by a node.

Raster Data Models

Raster data models divide geographic areas into cells identified by row and column.
The size of cells is chosen based on data accuracy and resolution.
Cells are classified based on common attributes.

Historical Development of Mapmaking

Mapmaking has been a significant part of human history, predating written communication.
Maps have been used to define, explain, and navigate the world.
Technical advances have made maps larger, more detailed, and accurate.

Advances in Mapmaking and GIS

The advancement of Geographic Information Systems (GIS) has led to the development of more sophisticated mapping systems.
GIS has led to the creation of more accurate and detailed maps.

Components of GIS

Hardware components include computers, printers, plotters, and scanners.
Methods include well-designed plans and procedures for applying technology.
Software components include GIS software, database software, OS software, and network software.
Data components include vector, raster, image, and attribute data.

Geographic Data

Geographic data is a crucial component of GIS.
Types of geographic data include vector, raster, image, and attribute data.

Global Positioning System (GPS)

GPS is a satellite network used to determine a place's exact location.
GPS receivers connected to multiple satellites orbiting Earth provide users with their location.

Digitizers

Digitizers convert analogue or paper images into digital formats on computers.
Instruments used include table digitizers, scanners, and smartphones.
Digitizer data provides geo-referenced information.

Geographic Data Representation

Geographic data representation involves graphical visualization of data or producing maps.
There are two main forms of representation: hardcopy (analogue) and digital.
Digital representation offers advantages over paper maps, including easy copying, high-speed transmission, storage density, and transforming, processing, and analysis.