The trip distribution calculation using the gravity model for two iterations.
Answer to Problem 9P
The trip distribution calculation using the gravity model for two iterations is shown below.
Explanation of Solution
Given:
The given table for number of productions and attractions in each district and travel time in minutes is
District | Productions | Attractions | Travel time (min) | |||
Table (1)
The given table for travel time versus friction factor is
Time(min) | ||||||||||||
Table (2)
Formula used:
The equation to calculate the number of attractions is given by
Here,
The equation to calculate the number of trip between each district is given by
Here,
Calculation:
Trip distribution for district
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Trip distribution for district
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Trip distribution for district
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Trip distribution for district
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The table for the above calculated values is shown below.
District | Computed P | Given P | ||||
Computed A | ||||||
Given A |
Table (3)
The adjusted value for district
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The adjusted value for district
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The adjusted value for district
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The adjusted value for district
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Carry out second iteration for each district with adjusted values.
Trip distribution for district
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Trip distribution for district
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Trip distribution for district
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Trip distribution for district
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The table for the above calculated values is shown below.
District | Computed P | Given P | ||||
Computed A | ||||||
Given A |
Table (4)
Conclusion:
Therefore, the trip distribution calculation using the gravity model for two iterations is shown above.
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Chapter 12 Solutions
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