NETWORK ANALYSIS

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NETWORK ANALYSIS
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• Introduction

• Network-enabled line themes
• Generating efficient travel routes
• Travel directions
• Determining/location closest facilities
• Service areas

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• Network-enabled line themes vector data

• Based on basic vector line themes

• Directionality is explicit
• Connectivity must be enforced

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• Network-enabled line themes attribute structure

• Specific attribute coding for network analysis
  functions
• Cost field(s) determine impedance to travel
• Cost can be assigned by line length, time of
  travel, or any supported user-defined impedance
  field
• Travel routing is determined by the cumulative
  cost of motion

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• Network-enabled line themes cost fields

• Supported Cost attributes and field names

Cost Unit Field Name seconds SECONDS minut
es MINUTES DRIVETIME IMPEDANCE
TRAVELTIME hours HOURS millimeters MILLI
METERS centimeters CENTIMETERS meters METE
RS kilometers KILOMETERS inches INCHES yar
ds YARDS feet FEET miles MILES nautica
l miles NAUTICALMILES non-time/non-distance
units, such as monetary units COST or UNITS
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• Network-enabling line themes

• Attributes must be edited for each arc
• Network turntables must be created (if turn
  impedances will be used)

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• Network-enabling line themes attribute editing

• Attributes must be edited for each arc
• Travel Cost (1 or more fields)
• One-way flagging
• Overpasses and underpasses
• Closed/dead end streets

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• Network-enabling line themes Network turntables

• If turn impedances will be used
• Create node numbers (automatically done while
  performing 1st routing operation)
• Use sample scripts to copy node numbers to arcs
• Create a turntable for each node containing
  required fields
• NODE
• ARC1 and ARC2 (from and to arc ID numbers)
• Supported Cost field
• Prohibited turns

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• Generating efficient travel routes prepare view

• Network-enabled line theme
• Stops point theme(s)

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• Generating efficient travel routes define problem

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• Generating efficient travel routes solved problem

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• Travel directions

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• Travel directions

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• Determining/location closest facilities

• Spatial relationship between points
• Point to point routing along linear network
• Different from routes where multiple stops are
  used
• Closest facility really means lowest cost
  facility
• Costs are user-supplied as in other network
  functionality

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• Determining/location closest facilities define
  problem

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• Determining/location closest facilities solved
  problem

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• Determining/location closest facilities travel
  directions

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• Generate service areas define problem

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• Generate service areas solved problem