F correct answers T/F?
GIS is a computerized system for making maps.
F correct answers T/F?
GIS is a tool for storing maps and pictures.
T correct answers T/F?
GIS is a computer-based system to store, manipulate, and output geographical data.
F correct answers T/F?
GPS units used by the military have higher PDOP than normal GPS units.
F correct answers T/F?
GPS works better during the day, when the clouds help improve the signals.
F correct answers T/F?
GPS cannot work at all in the forests, even if the canopy is sparse.
F correct answers T/F?
The signals we obtain with normal GPS today contain random error introduced by the military.
F correct answers T/F?
Post-processing requires a special kind of GPS called Differential GPS.
T correct answers T/F?
Measurements of Cartesian coordinates are in meters.
T correct answers T/F?
Measurements of geographic coordinates are in degrees.
T correct answers T/F?
DOQQs are digital aerial photographs.
T correct answers T/F?
A raster model consists of pixels and therefore can require a large amount of storage.
T correct answers T/F?
A vector model consists of objects (points, lines, and polygons) that take up less storage
F correct answers T/F?
Metadata are a huge database that consists of both vector and raster models.
F correct answers T/F?
Selective availability allows the GPS user to select the proper frequency (L1 or L2).
, Measurement Offsets correct answers When you adjust all of your positions relative to both the
receiver and base station. The differences between them is called?
- 32 satellites
- 1 orbit in 12 hours
- triangulation, 3 satellite for 2D
- 4 satellites for 3D test
- operated by DoD correct answers What is GPS? Explain the basis of GPS and how it works.
Less than or equal to 4 correct answers What range should you ideally attempt to maintain PDOP
within?
Post Processing correct answers The process of first collecting GPS data in the field and later
applying corrections to those data is often termed _______.
Selective Availability correct answers A random component put into a GPS that made readings
less accurate in the year 2,000.
Survey-grade GPS is used by the military and is able to use both L1/L2 bands which gives a
submeter accuracy reading. Consumer-grade GPS used the L1 band which does not give as good
of a reading. correct answers Why are survey-grade GPS more accurate than commercial-grade
GPS?
D correct answers Differential GPS
a. Relies on use of base stations in addition to the GPS receiver
b. The GPS data are adjusted in real time
c. Generally results in increased accuracy of geographic fixes
d. All of the above
e. None of the above
Geoid correct answers A is a smooth, mathematical representation of the Earth's surface that best
fits the global mean sea level.
Datum correct answers A is a set of referenced points against which position measurements were
made.
NAD27 has 20,000 reference points and has a center at Meades Ranch, Kansas. NAD83 has
270,000 reference points and has a center at Earth's center. correct answers What are the main
differences between NAD27 and NAD83?
10 correct answers The difference between NAD 83 and WGS84 can be up to ___ meters.
Azimuthal, conic, and cylindrical. Azimuthal is a plane (square) projection on earth. Conic is a
cone projection and a cylindrical is where it touches the earth. correct answers What are the 3