4654
Maximum surface roughness is reduced by 54 % and the number of layers with increased surface roughness relative to the steady-state value is reduced by 60 % .
 surface roughness, number of layers, surface roughness
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 surface roughness, number of layers, surface roughness