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Owing to a lack of standards and codes for the ultrasonic inspection of WAAM samples ( Lopez et al. , 2018 ) , a calibration method and step-by-step inspection strategy were introduced and then used to estimate the size and shape of an unknown lack of fusion ( LoF ) indication .
 concept or principle: standards; process characterization: ultrasonic inspection; manufacturing process: WAAM; concept or principle: samples; concept or principle: calibration; process characterization: inspection; concept or principle: fusion
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: standards, ultrasonic inspection, WAAM, samples, calibration, inspection, fusion 
Answer:
 concept or principle: standards; process characterization: ultrasonic inspection; manufacturing process: WAAM; concept or principle: samples; concept or principle: calibration; process characterization: inspection; concept or principle: fusion