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In relation to lightweight design for AM , four groups of methods and tools can be identified : topology optimization , generative design , lattice structure filling , and bio-inspired design .
 concept or principle: lightweight; engineering feature: design; manufacturing process: AM; machine or equipment: tools; material: be; engineering feature: topology optimization; enabling technology: generative design; engineering feature: lattice structure; engineering feature: bio-inspired design
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: lightweight; engineering feature: design; manufacturing process: AM; machine or equipment: tools; material: be; engineering feature: topology optimization; enabling technology: generative design; engineering feature: lattice structure; engineering feature: bio-inspired design