Compare

*Comparison

Table 1. Comparison with other systems.

	Subway	PRT	BT	Remark
Capacity (persons/h)	54 K	2~6 K	18~360 K	Highest Capacity
Moving speed (km/h)	35	20~40	100~162	Swiftest moving
Vehicle price ($)	800~1500 K	20~250 K	20~40 K	Cheapest price
Stopping method	On-line	Off-line	Branch-line	Best structure

Table 2. Expected line capacity and alighting capacity of the BT system.

LINE CAPACITY		Effective traffic volume (vehicles/h)				TERMINAL CAPACITY	Embarking/disembarking capacity (vehicles/h)
Headway (s)	Capacity/ lane/h (vehicles/h)	Number of the mainline lanes				Berth arrangement type	Number of berths
Headway (s)	Capacity/ lane/h (vehicles/h)	2	4	6	10	Berth arrangement type	4	6	8	12
0.5	7200	7200	14400	21600	36000	Reversible	360	540	720	1080
1.0	3600	3600	7200	10800	18000	Multi-series	1200	1800	2400	3600

If 10-seater cars are used, the capacity is 36,000~360,000 persons/h.

Table 3. Comparison of the characteristics.

Classification	Comparative Item	SUBWAY (in Seoul)	BT (estimated)	Remarks
Cost	Weight of train/vehicle	300~430 ton	1 ton	Reduced by a factor of 300
	Construction cost per km (whole costs)	$100 million	$60 million	BT: two-lane elevated. Subway in USA was $ 80~120 million.
	Fare	$2.0	$1.5	For a distant of 10 km
	20km construction period	60 months	12 months	BT: two elevated lanes
Mobility	Carrying capacity (ppdph)	54,000	360,000	BT: maximum of 3 lanes per direction
	Travel speed per hour	35 km	102 km	Subway:35km/h
	Peak hourly volume (Throughout the whole of Seoul)	420,000 persons	1,800,000 persons	Subway: 7 lines (218km) BT: 600km (total length)
Accessibility	Number of stations/terminals	197 each	800 each	Four times including various and direct
Accessibility	Distance between stations	1,100 m	500 m	Point at which traffic occurs.

PRT Analysis
The carrying capacity of PRT is too small.
If a PRT is operated using eight stations with three berths, then 1400 vehicles per hour can be managed. (350 vehicles per hour per station times four)
If each vehicles has three passengers, then the capacity is 1,400×3= 4,200 passengers per hour.
If there are 1.4 passengers per vehicle, then the capacity is 1,400×1.4= 1,960 passengers per hour.
Therefore, such a system carries less than 2,000 passengers per hour.

The headway must be below 2.5 seconds.
The vehicles rate must be over 40 vehicles per km (1000 m/(2.5 s × 10 m/s))

A capacity of 2,000 passengers per hour can be achieved using a system that has

* Eight stations having 24 berths (8 x 3 = 24),

* a headway time of under 2.5 s,

* a vehicle density of over 40 vehicles per km, and

* a well coordinated operating system.

BT Analysis
A high-speed operation of the BT system will be ensured by,

1. A high degree of straightness from installation along the center of wide roads.

2. High-speed passing on the connecting ramps of interchanges is possible owing to the large turning radius of the interchange.

3. Ample acceleration when entering the main line from a branch line, and deceleration when turning onto a branch line.

4. Traveling conditions are similar to those of an expressway.

A high-frequency service from the BT system can be guaranteed because,

1. It is a structure in which many vehicles can enter the main lines in a continuous manner from multiple terminals that contain many berths in a row.

2. The interchange structure enables high-speed operation and maintains vehicles at regular intervals on the main lines by employing large radius ramps.

3. The terminal structures have ample alighting capacity for multiple vehicles entering from main lines that provide a high-frequency service.

Factors determining a high capacity.

1. High speed running.

2. High frequency service.

3. Multi-lanes.

4. Terminals have structures that enable a high alighting/entering capacity.