Two different speed distributions are assigned in the

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Unformatted text preview: passing lane. They first check the speed of the transporter on the driving lane to determine the needed space for lane changing. According to the difference in the speeds of the transporter on passing lane and driving lane, the needed space for the transporter on the passing lane is determined. The space is also dependent on the vehicle type. If the speed of the transporter on driving lane is greater than the speed of the transporter on the passing lane, the transporter on the passing lane requires more lag gap for lane changing, else it requires more lead gap. The required space for lane changing according to the difference in speeds of passing lane transporter and driving lane transporter are given in Table 16. If the required space is available, transporter with the entity on the passing lane advances to the next station on the driving lane, else it continues on passing lane to the next station. Same procedure continues at the stations, which are 1250 feet, 1000 feet, 900 feet, 800 feet, 700 feet, 600 feet, 500 feet, 450 feet, 400 feet, 350 feet, 300 feet, 250 feet, 200 feet, 150 feet, 100 feet, and 50 feet in advance of the passing lane closure taper for the transporters on the passing lane. The transporters on the driving lane move through the road by adjusting their speeds according to the merging traffic from the passing lane when needed. 78 When the transporters on the passing lane did not merge to the driving lane until the lane closure taper, they first check the number of vehicles waiting at the lane closure taper station on passing lane. If there are: - 3 or less vehicles waiting at the taper, they require the space values given in Table 20 for lane changing. - More than 3 and 5 or less vehicles waiting, they require the space values given in Table 21 for lane changing. - More than 5 and 10 or less vehicles waiting, they require the space values given in Table 22 for lane changing. - More than 10 vehicles waiting, they require the space values given in Table 23 for lane changing. If there is no space available for merging, the transporters stop and wait at the taper until they find the required space for lane changing. The transporters on the driving lane continue on driving lane by adjusting their speeds when needed because of the merging transporters from passing lane. After the taper, the road becomes a one- lane road and all the vehicles on driving lane and passing lane continue on this one- lane road until they leave the system 750 feet after the lane closure taper. 79 DRIVING LANE Assumptions PASSING LANE Assumptions: START START Entity Arrival (Probability Distribution according to the Time of the Day) Entity Arrival (Probability Distribution according to the Time of the Day) Truck Percentage=39% on driving lane Truck Percentage= 9% on passing lane Assign Entity Type (Truck or Car) Assign Entity Type (Truck or Car) NO NO Transporter Car: Initial Velocity= 95 ft/sec (free flow speed) Vehicle Length= 20 ft (4 ft added to the average passenger car length to prevent collision when the vehicles stopped) Entity Type = Car Assign Transporter to Entity Truck Truck YES Assign Transporter to Entity Car Car Transporter Truck: Initial Velocity= 95 ft/sec (free flow speed) Vehicle Length= 65 ft (5 ft added to the average truck length to prevent collision when the vehicles stopped) Entity Type = Car Assign Transporter to Entity Truck YES Assign Transporter to Entity Car Truck Figure 23: Flowchart of the ARENA Traffic Simulation Model Car Explanations: Inter-arrival Time (IAT) Distribution is dependent on the number of vehicles per hour per lane according to the time of the day Assign entity (vehicle) types according to the truck and car percentages from the actual data. Decide entity (vehicle ) type for the transporter assignment Assign Transporter Car or Transporter Truck according to the entity (vehicle) type Transporter Car and Transporter Truck have the same properties for both lanes. 80 DRIVING LANE Assumptions Assign different speeds for the transporters using Normal Distribution with mean 88 ft/sec and standard deviation 3.47 ft/sec Assign different speeds for the transporters using Normal Distribution with mean 75 ft/sec and standard deviation 10.27 ft/sec Assign Speed Distribution Assign Speed Distribution Transport on Mainline until the Left Lane Closed Ahead Sign Transport on Mainline until the Left Lane Closed Ahead Sign Arrive to the First "Left Lane Closed Ahead" Sign Station Arrive to the First "Left Lane Closed Ahead" Sign Station Assign New Speed at the "Left Lane Closed Ahead" Sign Assign New Speed at the "Left Lane Closed Ahead" Sign Truck Car PASSING LANE Assumptions: Assign different speeds for the vehicles using Normal Distribution with mean 97 ft/sec and standard deviation 3.67 ft/sec Assign different speeds for the vehicles using Normal Distribution with mean 84 ft/sec and standard deviation 8.8 ft/sec Explanations: Assign Speed Distribution Assign Speed Distribution Transport on Mainline until the Left Lane Closed Ahead Sign Transport on Mainline until the Left Lane Closed Ahead Sign Arrive to the First "Left Lane Closed Ahead...
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