564
The BESO method , which allows the material to be added and removed simultaneously during the optimization process , is an extension of the original evolutionary ESO method proposed by Xie and Steven .
 concept or principle: BESO method; material: material; material: be; concept or principle: optimization
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: BESO method; material: material; material: be; concept or principle: optimization