547
Topology optimization a mathematical method capable of rearranging the materials to attain desired properties while satisfying prescribed constraints can complement the trial-and-error approach and provide a powerful tool to design complex scaffolds with features on multiple scales .
 engineering feature: Topology optimization; concept or principle: mathematical; concept or principle: materials; concept or principle: properties; concept or principle: trial-and-error; machine or equipment: tool; engineering feature: design; engineering feature: scaffolds
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: Topology optimization; concept or principle: mathematical; concept or principle: materials; concept or principle: properties; concept or principle: trial-and-error; machine or equipment: tool; engineering feature: design; engineering feature: scaffolds