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Conventional porous scaffolds typically consist of a vast number of randomly shaped pores in different sizes and therefore it is almost impossible to quantitatively analyse their properties .
 engineering feature: porous scaffolds; machanical property: pores; concept or principle: quantitatively; concept or principle: properties
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:
 engineering feature: porous scaffolds; machanical property: pores; concept or principle: quantitatively; concept or principle: properties