Test 4 Flashcards
(32 cards)
True or False: In order to calculate three-dimensional, vertical position (x,y,z), three GNSS satellites are needed.
False, FOUR GNSS satellites are needed.
True or False: The first GPS satellite launch in 1978, while the full constellation was achieved in 1994.
TRUE
Match the following terms with a correct example of each:
Observation
Triangulation
Trilateration
GPS
Map and Compass
Landmarks
Observation -> Landmarks
Triangulation -> Map and Compass
Trilateration -> GPS
Which of the following locations calculates an unknown position using a previous known position and is used by animals and humans.
Landmarks
Celestial Naviagation
Dead Reckoning
Dead Reckoning calculates an unknown position using a previous known position and is used by animals and humans.
Place the following steps of using triangulation to identify your location in the correct order:
- Repeat process for landmarks 2 and 3 Your position is at the intersection of the three lines
- Sight a field bearing to landmark 1 and transfer bearing line to map
- Align map and compass to north
- Find three landmarks in field and label them 1, 2, 3 on map
- Align map and compass to north
- Find three landmarks in field and label them 1, 2, 3 on map
- Sight a field bearing to landmark 1 and transfer bearing line to map
- Repeat process for landmarks 2 and 3 5. Your position is at the intersection of the three lines
Match the following elements of a GPS position with the correct definition.
Position status
Height Above Ellipsoid (HAE)
Position Averaging
Streaming Position
Position status -> 2D, 3D, differential, etc.
Height Above Ellipsoid (HAE) -> Altitude expressed as height above datum
Position Averaging -> Positions averaged into a single point
Streaming Position -> Logged when moving
An element of a GPS position altitude expressed as height above datum
height above ellipsoid
Elements of a GPS position:
Positions averaged into a single point is called what?
Position averaging
Elements of a GPS position
What does streaming position do?
Logged when moving
Which of the following is NOT an error that degrades the accuracy of a GPS location?
Position Error (PE)
Elevation Mask Altitude
Dilution of Precision (DOP)
Signal to Noise Ratio (SNR)
Elevation Mask Altitude
A ___________ GPS is a correction message transmitted to GPS receivers to account for error.
differential
A ___________ GPS is a correction message transmitted to GPS receivers to account for error.
Name one example of a Satellite Based Augmentation System (SBAS) , or correction computed from base stations and uploaded to geostationary satellites.
WAAS
EGNOS
GAGAN
MSAS
SDCM
T or F In order to collect sub-meter accuracy horizontal coordinates using a GPS receiver, you would need to spend extra money on a Mapping-Grade GPS, not just use a Recreational-Grade GPS.
False -
The Validation step occurs in the ____ stage of the Field Data Workflow
Assimilation
Any field data you collect should be validated on a ___ basis
daily This ensures that you identify any issues in your data schema, collection workflow, or data collected at the beginning of the project, rather than then end.
The three stages of the Field Data Workflow are ->
Preparation>Collection>Assimilation
Data Dictionary is another term for describing the ___ ___ - the feature and field names and types.
data schema
Data Dictionary is another term for describing the ___ ___ - the feature and field names and types.
While Conceptual Data Model, Training Course, and Metadata all describe the data - none of them…
specifically describe the feature and field names and types.
Match the following feature-level GPS metadata terms with their description.
Fix Type
EPE
PDOP
Correction Age
Overall Positional Accuracy
Time Since Differential Received
Horizontal and Vertical Accuracy
2D, 3D, DGPS
Fix Type > 2D, 3D, DGPS
EPE > Horizontal and Vertical Accuracy
PDOP > Overall Positional Accuracy
Correction Age > Time Since Differential Received
It’s a good practice to always use this coordinate system when collecting field data.
WGS 1984 Geographic Coordinate System It’s a good practice to always use WGS 1984 Geographic Coordinate System (GCS). WGS 1984 GCS is an unprojected spherical coordinate system in latitude and longitude coordinates and degrees, minutes, and seconds units. It’s one of the most basic coordinate systems and available in every GPS receiver and smartphone app. If you always collect data in WGS 1984 GCS, then you don’t have to remember what coordinate system you collected the data. Also, it’s very easy to transform WGS 1984 GCS into whichever coordinate system you might be using for your project.
T or F: A map appears in Collector if you created it or if you are a member of a group with which the map is shared in ArcGIS Online or ArcGIS Enterprise. The map must also be enabled for use in Collector.
True
Review the settings in the following ArcGIS Pro Share As Web Layer geoprocessing tool used to publish the Hydrants Web Layer. Which option enables users to perform edits to the Web Layer without being connected to ArcGIS Online via the Internet?
Enable Sync allows disconnecting editing while not logged into ArcGIS Online via the Internet. Enable editing allows features to be added, deleted, and updated. Export Data allows users to export all the features in the Web Layer. Allow geometry updates without m-value allows you to add features without updating the m-value for feature classes with measures.
How can you tell if you can edit the Hydrant web layer features in this ArcGIS Online web map, Collector for ArcGIS, and ArcGIS Pro?
Yes you can edit the features. Here are some clues: (1) the Edit button is visible; (2) click they Hydrants layer More Options… button to see that you can Disable/Enable Editing; (3) click a hydrant feature and note the option to Edit the attributes. If you can edit the features in an ArcGIS Online web map, it also means you can edit the feature in Collector for ArcGIS and ArcGIS Pro.
When adding a hydrant feature, which of the following is NOT a value included in the Coded Value Domain assigned to the Manufacturer field? American Darling British Engineering Clow Corporation Corey
The coded value domain assigned to the Manufacturer field includes all the values listed in the dropdown box when adding or updating the attribute. British Engineering is not included in the list of possible values.
