593
4 Current status of AM and topology optimization in producing porous metallic structures AM technologies are superior to conventional fabrication techniques for producing porous metallic implants with complex and customized structures , as shown in 5 .
 manufacturing process: AM; engineering feature: topology optimization; engineering feature: porous metallic structures; manufacturing process: AM technologies; manufacturing process: fabrication; application: porous metallic implants; material: as
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:
 manufacturing process: AM; engineering feature: topology optimization; engineering feature: porous metallic structures; manufacturing process: AM technologies; manufacturing process: fabrication; application: porous metallic implants; material: as