Effect of Rolling-Press Pretreatment on Drying Rate and Pit Structure of Oak(Quercus mongolica)Lumber THE THREE-DIMENSIONAL FLOW-RESISTOR NETWORK FOR RADIAL AND TANGENTIAL GAS PERMEABILITY OF SOFTWOODS THE FLOW-RESISTOR AND GAS PERMEABILITY OF SOFTWOOD TRACHEID THE THREE-DIMENSIONAL FLOW-RESISTOR NETWORK FOR LONGITUDINAL GAS PERMEABILITY OF SOFTWOODS