Gis Exam 1

Front 1

GIS definition

Back 1

Geographic Information System:

Computer based system to aid in the collection, maintenance, storage, analyzation, output, and distribution of spatial data/info.

Front 2

6 Aspects of GIS

Back 2

Data, Software, Method, People,

Network, Hardware

Did Some Man Poop Near Here

Front 3

Aspects of Hardware

Back 3

Computers

Input

Printing

Disk Space

Front 4

Aspects of Network

Back 4

Dissemination of data

Display of info

Front 5

Aspects of Methods

Back 5

Formulas

Statistics

Analysis

Algorithms

Front 6

Aspects of Software

Back 6

Provides:

Manipulate

Store

Query

Analyze data

Front 7

What is the Geospatial Data Model

Back 7

Formal means of representing spatially referenced data

Front 8

What are the 2 different Spatial Phenomenons and their definitions

Back 8

Discrete - Individually Distinguishable and does not exist between observations (ex: lakes, rivers)

Continuous - exists between observations (ex: temperature, elevation)

Front 9

4 different types of attributes (catagorial)

Back 9

Nominal

Ordinal

Interval

Ratio

Front 10

Nominal attribute

Back 10

Naming that does not imply rank or order or size

Just naming (ex. movie name, color, plant type)

Front 11

Ordinal attribute

Back 11

implies rank/order but not scale

Front 12

Interval Attribute

Back 12

implies rank/order and scale but no natural zero (ex. temperature, can be added but not multiplied)

Front 13

Ratio Attribute

Back 13

Rank, order, and magnitude, has natural zero

(ex. mph, height)

Front 14

Identify

(A) (B) (C) (D)

ID height(ft) Type Class

1 15 pine Med

2 20 pine Med

3 8 mesquite Small

4 30 oak Tall

Back 14

A) = Nominal

B) = Ratio/interval

C) = Nominal

D) = Ordinal

Front 15

Attribute Data Types (number)

Back 15

The data type of the attribute needs to be specified for the efficient use of memory and determination of the operation applicability.

Integer

Float/real

Text/String

Date

Front 16

Integer attribute

Back 16

whole numbers

Front 17

Float/Real Attribute

Back 17

numbers with decimals

Front 18

Text/string attribute

Back 18

numbers and letters but can't be used to calculate (aka a address)

Front 19

Date

Back 19

Dates (12/25/2015

Front 20

What are the three Spatial Data Models

Back 20

Raster

Vector

Triangulated Irregular Network (TIN)

Front 21

Vector Data Models + 3 basic vector types

Back 21

Defines Discrete models

types: points, lines, and polygons

Composed of coordinates and attributes

Front 22

Point

Back 22

Uses a single coordinate, no dimension

(ex: light poles, manholes)

Front 23

Lines:

-node

-vertex

Back 23

Uses ordered set of coordinates

Each line (& curve) is made up of multiple line segments, occasionally curves are represented mathematically

node= starting point

vertex= intermediate point of line

(ex: road, pipeline, outlines, river)

Front 24

Polygons

Back 24

Formed by set of connected lines

Must close

Have interior region

(ex: lake, city, tree stand, political boundary)

Front 25

What is a Raster Model

Back 25

Represents continuous objects (ex: temp. elevation)

Regular set of cells in a grid (matrix)

Real-world objects are represented by values in the grid cells

Front 26

Raster vs. Vector

Back 26

Raster

- Good for frequent changes - Simple

- Easy Overlays - Best for digital imagery

Vector

- Compact - Great for network and linear features

- People are more familiar with vector

- Can obtain topo

Front 27

What is a TIN - triangulated irregular networks

Back 27

A network of triangles connected by 3D surface

- triangles do not cross

More complex than rasters (More efficient space-wise)

TIN preserves each measurement point

Front 28

(A) Two types of data sources

Back 28

A). Hardcopy and Digital

Hardcopy is stable cheap portable but reusable and not easily updatable.

Digital is cheap, stable, updatable but its not portable, requires hardware that may be specific

Front 29

Coordinate Transformation aka Registration

Back 29

aka georectification

Brings spatial data into an Earth-based map coordinate system using control points

Front 30

What is are Control Points def. and guidelines

Back 30

Used to transform data from digitizer coord. system to map coord. system

1. Should provide highest accuracy

2. Accuracy should be good positional accuracy

3. Should be evenly distributed

From previous maps and land surveys

Front 31

What is Digitizing

Back 31

process of converting coordinates of features from a data source into digital format

methods:

1. manual

2. automatic

Front 32

What is are the two Digitizing errors

Back 32

overshooting the vertices or nodes

undershooting the vertices or nodes

Front 33

Manual versus Automatic digitizing

Back 33

Manual

pro:

- accurate - Short training - Humans interpret better

- lower initial capital (no programer)

con:

map scale, operator, and equipment impacts accuracy

Automatic

pro:

- good for large projects

- no initial operator cost - works well with large # of operators

cons:

- expensive - requires manual editing

- only translates, not interpret - scanner errors

Front 34

What is Feature Generalization

Back 34

approx. and simplification of real features when represented on a map

Front 35

What are the Methods of Generalization

Back 35

Fused

Simplified

Exaggerated

Displaced

Omit

Front 36

Map def. and purpose

Back 36

Definition:

A graphic representation of a milieu

Milieu = cultural and social impacts

Purpose:

Way to transmit knowledge

Front 37

Different types of Maps

Back 37

Reference = emphasis on location, political map (roads maps)

Thematic = Emphasis on attributes, show one subject, one theme (ex: educational level, political affiliation)

Front 38

Two types of thematic maps

Back 38

Qualitative = show nominal data (time zones)

Quantitative = show numerical data, variation from place-to-place (population density, political map)

Front 39

Cartographic Process/Define steps after seeing them

Back 39

1. Define purpose and meaning

2. Choose scale

3. Determine map format, limitations printing, and economics of re/production

4. Abstract and generalize (only meaningful info, organize necessarily to communicate well, keep simple)

5. Design Layout (scale, title, legend, inlet map, credits)

Front 40

Map Scales

Back 40

Large Scale = 1:0 - 1:600,000

Med. Scale = 1:600,001 - 1:2,000,000

Small Scale = 1:2,000,001 - 1:infinite

Front 41

Four methods to abstract and generalize

Back 41

Selection

Classification

Simplification

Symbolization

Front 42

Graticule

Back 42

Visual representation of coordinate system or location scheme

Front 43

NSDI

Back 43

National Spatial Data Infrastructure

Front 44

DRG

Back 44

Digital Raster Graphic (Georeferenced double check tool)

Front 45

Digital Orthophoto Quadrangle (DOQ)

Back 45

Scanned photos (raster) backgrounds

Front 46

Map Properties (4)

Major and minor

Back 46

Can have one or more perfect but not all four

Major: Mutually exclusive

- Area

- Shape

Minor Properties: Cannot exist all of the time

- distance

- direction

Front 47

Maps that preserve Area (equivalent maps)

Back 47

Albers Equal Area

Sinusoidal

Front 48

Maps that preserve shape (conformal Map)

Back 48

couldn't tell

Front 49

preserves neither shape or area

Back 49

Goodes Homolosine Map

Robinson Map