Deck 17: Least Cost Path and Network Analysis

Question 1

Link impedance for network applications can be measured by:

A) physical length
B) travel time
C) both of these are correct

Answer 1

both of these are correct

Question 2

What is the main objective of the "vehicle routing problem"?

Answer 2

No Answer

Question 3

Explain the difference between a network and a line shapefile.

Answer 3

No Answer

Question 4

A shortest-path analysis can include intermediate stops between the origin and destination.

Question 5

A ____ link connects a cell to one of its immediate neighbors, and a ____ link connects the cell to one of its corner neighbors.

A) lateral, diagonal
B) diagonal, lateral

Question 6

The diagram below represents a cost raster, with the origin at the upper left corner. (1) What is the cost for moving from (col. 1, row. 1) to (col. 2, row 1)? (2) What is the cost for moving from (col. 1, row. 1) to (col. 2, row 2)? (3) What is the least accumulative cost from (col. 1, row. 1) to (col. 2, row 3)?

Question 7

Least-cost path analysis is _____based, and network analysis is _____based.

A) vector, vector
B) raster, raster
C) vector, raster
D) raster, vector

Question 8

Explain the role of a source raster in least cost path analysis.

Question 9

How does the surface distance differ from the regular (planimetric) cost distance?

Question 10

Explain the difference between the minimum impedance model and the maximum coverage model for location-allocation analysis.

Question 11

The surface distance measure is calculated from a(n):

A) path raster
B) allocation raster
C) elevation raster
D) cost raster

Question 12

In ArcGIS a network dataset can be built from:

A) a shapefile
B) a geodatabase
C) both of these are correct

Question 13

A raster that assigns each cell to its closest source cell on the basis of cost distance measures is called a(n):

A) allocation raster
B) none of these are correct
C) direction raster
D) shortest path raster

Question 14

Define "allocation analysis."

Question 15

In an allocation analysis, the service area of a fire station will _____ if the response time increases:

A) increase
B) decrease

Question 16

Explain the difference between the physical distance and the cost distance in distance measure operations.

Question 17

One-way streets are treated as ______in network analysis:

A) link impedance
B) turn impedance
C) none of these is correct
D) restriction

Question 18

The surface distance _______ when the elevation difference between two cells _______.

A) increases, decreases
B) increases, increases

Question 19

The cost in a cost raster usually represents the sum of a number of cost factors.

Question 20

If the speed limits are lowered (e.g., from 30 miles/hour to 20 miles/hour) on a network, then the service areas of a fire station will ________ in an allocation analysis:

A) decrease
B) increase

Question 21

Which of the following is a common data source for building a road network in the United States?

A) Satellite imagery
B) DEM
C) DOQ
D) TIGER/Line files

Question 22

Which of the following is true about location-allocation analysis?

A) Both a location-allocation analysis requires inputs in supply, demand, and distance measures and a a model or algorithm for problem solving.
B) A location-allocation analysis requires inputs in supply, demand, and distance measures.
C) Distances may represent shortest-path distances on a road network or straight-line distances.
D) A location-allocation analysis requires a model or algorithm for problem solving.
E) All of these are correct

Question 23

What is turn impedance?

Question 24

Provide an example to support the statement that a road network must have the topological relationship of connectivity before it can be used for network analysis.

Question 25

Name three network attributes that are normally needed for traffic analysis.

Question 26

Shortest-path analysis is used to solve the closest facility problem.

Question 27

Use an example to explain how a "cost raster" is put together by using different factors.

Question 28

Both raster-based least cost path analysis and vector-based shortest path analysis use Dijkstra's algorithm. Explain in general terms how Dijkstra's algorithm works.

Question 29

Cost distance measure operations are based on the node-link cell representation. Explain this representation with a diagram.