3811
Optical Emissions Spectroscopy and plume imaging were utilized to investigate flaws generated during directed energy deposition additive manufacturing .
 process characterization: Optical; concept or principle: Spectroscopy; application: imaging; concept or principle: flaws; manufacturing process: directed energy deposition additive manufacturing
Given options, please tell me the categories of all the listed entity words.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} 
 Entities: Optical, Spectroscopy, imaging, flaws, directed energy deposition additive manufacturing 
Answer:
 process characterization: Optical; concept or principle: Spectroscopy; application: imaging; concept or principle: flaws; manufacturing process: directed energy deposition additive manufacturing