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A round robin test was conducted as follows : a series of standard test procedures ( part sizes and shapes and test protocols ) were applied – using one microCT system – to identical parts produced on a variety of metal additive manufacturing systems ( specifically laser powder bed fusion systems ) .
 round robin test, as, standard, protocols, microCT, metal additive manufacturing, laser powder bed fusion systems
Please list all entity words in the text that fit the category. Output format is "word1, 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:
 round robin test, as, standard, protocols, microCT, metal additive manufacturing, laser powder bed fusion systems