Exam 1

Question 1

Geographic information system

Answer 1

Linking where something is located on earth with what it is to help manage and use data

Question 2

Spatial data

Answer 2

Information about anything that is referenced to the earth

Question 3

Coordinate system

Answer 3

Locates data on a spherical surface (Lat/long)

Question 4

Projected coordinate system

Answer 4

Locates data go a flat surface (meters)

Question 5

Datum

Answer 5

Mathematical model that describes the shape of the earth

Question 6

What is the earths shape?

Answer 6

Ellipsoid

Question 7

Geodetic

Answer 7

Aligns the spheroid to fit a particular area

Question 8

Geocentric

Answer 8

Uses the earths center of mass as the origin

Question 9

Three main projections

Answer 9

1. Cylindrical (Mercator)
2. Conic
3. Azimuthal

Question 10

Transverse Mercator

Answer 10

Projects cylinder tangent to a chosen meridian

Question 11

WGS84

Answer 11

World geodetic system is a transverse Mercator projection standard for navigation

Question 12

Mercator

Answer 12

Projects on a cylinder tangent to the equator

Question 13

UTM projection

Answer 13

Universal transverse Mercator projection that projects the sphere onto a cylinder tangent to a central median

Question 14

Lambert conformal conic

Answer 14

Comic projected on a cone tangent at two standard parallels

Question 15

Orthographic

Answer 15

Azimuthal geometrically projected onto a plane point of projection is at infinity

Question 16

GDA94

Answer 16

Geocentric datum of Australia - current coordinate system for Australia

Question 17

Raster

Answer 17

Stores features as values within an equally spaced grid, always 2D

Question 18

Vector

Answer 18

Stores features as a series of points, connected into lines, and combined to form polygons (each point has x,y coordinate)

Question 19

Resolution

Answer 19

Length of the shortest line between two points

Question 20

Boolean

Answer 20

Questions that can only be answered with yes or no, or true or false. Data has only two possible values.

Question 21

Union (or)

Answer 21

Creates new data layer by overlaying two polygon layers. Combined, has attributes of both layers.

Question 22

Intersect (and)

Answer 22

Creates new layer by overlaying two sets of features. Layer contains features that are from both layers where overlap occurs.

Question 23

Identity

Answer 23

Creates new layer by overlaying two sets of features. Output contains all input features for one of the polygons and both for where overlap occurs.

Question 24

Clip

Answer 24

Cuts down a vector layer. Extracts a subregion of a layer that interests with a second layer, the clip.

Question 25

Erase

Answer 25

Input layer features that overlap of clip with the erase layer polygons are erased and not preserved

Question 26

Split

Answer 26

Breaks a single layer into many layers based on a defined attribute of a second layer, output is portions of the input where features are overlapped by specific polygons of the split

Question 27

Merge

Answer 27

Join multiple adjacent layers into one, spatial reference must match

Question 28

Eliminate

Answer 28

Merges selected polygon with neighbor that have the largest shared border or area between them

Question 29

dissolve

Answer 29

Merges adjacent polygons, lines or regions which have the same value for a specified attribute

Question 30

Buffer

Answer 30

Creates buffer polygon around specified input layer feature

Question 31

Topology

Answer 31

Mathematica of how spatial features join

Question 32

Key aspects of topology

Answer 32

1. Adjacency

2. Connectivity

Question 33

Mode

Answer 33

Point found at the end of a line

Question 34

Vertex

Answer 34

Point found within a line, gives a curved line it’s shape

Question 35

Landscape

Answer 35

A mosaic of different cover types

Ex: habitat, ecosystem or land use

Question 36

Landscape composition

Answer 36

Represents the types of habitat or land use within a landscape

Question 37

Landscape configuration

Answer 37

The amounts and arrangement of these habitats or land use in space

Question 38

Components of landscape

Answer 38

1. Amounts of differing land cover
2. Size of patches of land cover
3. Isolation of land cover types
4. Edges between land cover types

Question 39

Spatial data

Answer 39

Information about anything that is referenced to the earth

Question 40

Spatial database

Answer 40

1. Attributes
2. Location
3. Topology

Question 41

remote sensing

Answer 41

Satellite imagery that records continuous data, allows detection of change

Question 42

Differential GPS

Answer 42

Station set up over known surveying point, and signal is compared to the actual known location