2001
- Rough surfaces which depend on build angle might affect mechanical properties , with rough surfaces in inaccessible areas being unable to be processed .
 concept or principle: surfaces; process parameter: build; concept or principle: mechanical properties; concept or principle: surfaces; process parameter: areas; material: be
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: 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:
 concept or principle: surfaces; process parameter: build; concept or principle: mechanical properties; concept or principle: surfaces; process parameter: areas; material: be