英文關鍵字
abstract
air
architecture
blue
building
chemical
chimney
city
clean
concrete
electric
energy
engineer
equipment
factory
fuel
heat
heavy
industrial
industry
iron
ladder
line
machine
manufacturing
metal
oil
petrochemical
petroleum
pipe
pipeline
piping
plant
production
pump
refinery
reflection
resources
science
sign
sky
stainless
station
steel
structure
supply
technology
tower
tube
welding