Table 4. Cost factors and assumptions used for operation cost analysis.

Cost factor Operation machine
Combimachine Tower-yarder Processor
yarder processor HAM300 Excavator head
Purchase price (won) 455,000,000 120,000,000 147,400,000 110,000,000 110,000,000
Endurance perioda (years) 8 8 8 7 8
Economic life (hour) 8,000 8,000 8,000 9,744 11,136
Annual operation timeb (hour) 1,392 1,392 1,392 1,392 1,392
Fuel consumption (liter/hour) 4.2 5.3 5.4 9.3  -
Coefficient of repair and maintenance 0.7 0.7 0.7 0.8 0.9
Coefficient of lube oil 0.4 0.4 0.4 0.4 0.4
Interest rate (%/year) 10 10 15 15 15
Depreciation (won/hour) 56,875 15,000 18,425 11,289 9,878
Interest expense (won/hour) 16,343 4,310 7,942 5,927 5,927
Costs of repair and maintenance (won/hour) 39,813 10,500 12,898 9,031 8,890
Fuel costc (won/hour) 8,127 10,255 10,449 17,955  -
Other cost (won/hour) (Insurance, storage fee etc.) 8,531 2,250 2,764 1,693 1,482
Sub total 129,689 42,315 52,477 45,895 26,176
Labor costd (won/hour) (50% Inclusion incidental expense) 35,669 35,669 60,094 42,803
Total machine cost 165,358 77,985 112,570 88,698 26,176
(won/hour, Inclusion labor cost) 243,343 114,874
174 day×8 hour=1,392 hours (KFS, 2012)
Endurance period (Miyata, 1980; Woo et al., 1990; Brinker et al., 2002)
Diesel : 1,382 won/liters in 2019, South Korea (KNOC, 2019)
Standard of labor cost : machine operator (190,235 won), worker (130,264 won) in 2019 (CAK, 2019)