GIS review, Exam 2- Chapter 3, GIS,
GIS Exam 1 and 2, GIS - Midterm,
Geospacial Technology Chapter 1-3,
Geospatial, ArcGIS - ESRI, GIS Test
one, Geodesy - Week 4 - ESRI Online
Course, Geospatial Test 1, GeoScience
Final, Geospatial Data and Technology
Exam (1328 questions)
Define geospatial data. - ANSWER The data that describes both the
LOCATION and CHARACTERISTICS of spatial features (such as roads,
land parcels, and vegetation stands on the Earth's surface.)
What is GIS? - ANSWER Geographic Information Systems is a
computer system for capturing, storing, querying, analyzing and
displaying geospatial data.
Define geometries and attributes as the two components of GIS data. -
ANSWER Geometric data describe the locations of spatial features,
which may be discrete or
continuous.
Attribute data describe the characteristics of spatial features.
Explain the difference between vector data and raster data. - ANSWER
Vector data use points and their x-, y-coordinates to represent spatial
features of
points, lines, and areas.
Raster data use a grid and grid cells to represent the spatial variation of
a feature (such as elevation or precipitation.)
Vector Data Model: Explain the difference between the georelational
data model and the object-based data model. - ANSWER The
,georelational data model uses a split system to store spatial data and
attribute data.
The object-based data model stores spatial data and attribute data in a
single system.
Name two tools or techniques for vector data analysis. - ANSWER Tools
for vector data analysis include buffering, overlay, distance
measurement, spatial statistics, and map manipulation.
raster data analysis. - ANSWER includes local, neighborhood, zonal,
and global operations.
What is Topology? - ANSWER It expresses the spatial relationships
between features,
What is TIN? - ANSWER Triangulated Irregular Network.
Describe the 3 levels of approximation of the shape and size of the Earth
for GIS applications. - ANSWER SPHERE, SPHEROID/ELLIPSOID,
GEOID
What is datum? - ANSWER A mathematical model of the Earth, which
serves as the reference base for calculating the geographic coordinates
of a location.
Define Projection. - ANSWER The process of transforming from a
geographic coordinate system to a projected coordinate system. Can
also be reprojected onto another coordinate system.
Define Relational Database. - ANSWER A collection of tables in which
tables are connected by keys.
Define Geographic coordinate system. - ANSWER The location
reference system for spatial features on the Earth's surface using
latitude and longitude.
Explain the importance of map projection. - ANSWER First, a map
projection allows us to use 2 dimensional maps, either paper or digital,
,instead of a globe. Second, a map projection allows us to work with
plane or projected coordinates rather than longitude and latitude values.
Computations with geographic coordinates are more complex and
yield less accurate distance measurements.
Describe the 4 types of map projections by the preserved property. -
ANSWER A Conformal projection preserves local angles and shapes.
An Equivalent projection represents areas in correct relative size.
An Equidistant projection maintains consistency of scale along certain
lines.
An Azimuthal projection retains certain
accurate directions.
Describe the 3 types of map projections by the projection or developable
surface. - ANSWER A cylindrical projection uses a cylinder as the
projection or developable surface
A conic projection uses a cone
An azimuthal projection uses a plane.
Explain the difference between the standard line and the central line. -
ANSWER A standard line refers to the line of tangency between the
projection surface and the reference globe. In other words, there is no
projection distortion along a standard line.
The central lines (i.e., the central parallel and meridian) define the center
of a map projection.
How is the scale factor related to the principal scale? - ANSWER The
scale factor is defined as the ratio of the local scale to the principal
scale. In other words, the scale factor is the normalized local scale. Will
be 1 along the standard line and more distorted away from the line.
Name two commonly used projected coordinate systems that are based
on the
transverse Mercator projection. - ANSWER Universal Transverse
Mercator (UTM) grid system State Plane Coordinate (SPC) system.
Explain how a UTM zone is defined in terms of its central meridian,
standard meridian, and scale factor. - ANSWER A UTM zone is mapped
, onto a secant case transverse Mercator projection, with a scale factor of
0.9996 at the central meridian. The standard meridians are 180
kilometers to the east and west of the central meridian.
Explain the UTM coordinate system - ANSWER ...This system is a
specialized application of the transverse Mercator projection which is
both cylindrical and conformal. It divides the world into 60 numbered
zones, both north and south, separated by the equator. Each zone
spans six degrees of longitude and has its own central meridian. This
system was adopted by the US Army Map Service in 1947 for their use
in worldwide mapping and continues to be used worldwide. Florida falls
into UTM zones 16 and 17.
When using the UTM system, linear parameters are established. The
origin of each UTM zone is the intersection of its central meridian and
the equator, and the parameters are applied to this origin to make it
convenient to work with making all x and y values positive, or reducing
their range. The first parameter is the false easting - a linear value
applied to the origin of the x-coordinates - or the central meridian. The
second parameter is the false northing - a linear value applied to the
origin of the y-coordinates - or the equator. The final parameter used in a
UTM grid system is a fixed parameter called the scale factor. The scale
factor is a unitless value (usually less than one) that is applied to the
center point or line of a map projection to reduce the distortion of the
projection in the area of interest. The value of the scale factor for the
UTM system is 0.9996
Latitude and Longitude - ANSWER Latitude- parallel lines which run east
and west and measure distance north and south of the equator.
Longitude- "meridians" which run north and south and measure distance
east and west of the prime meridian.
, A geographic coordinate system.
UTM - ANSWER A coordinate system based on the Transverse
Mercator projection, developed in the 1940s. The globe is divided into 60
individual 6-degree wide longitudinal strips extending from 80S to 84N
