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Additive manufacturing ( AM ) is the umbrella term that covers a variety of techniques that build up structures layer-by-layer as opposed to machining and other subtracting methods .
 manufacturing process: Additive manufacturing; manufacturing process: AM; process parameter: build; concept or principle: layer-by-layer; material: as; manufacturing process: machining
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: Additive manufacturing; manufacturing process: AM; process parameter: build; concept or principle: layer-by-layer; material: as; manufacturing process: machining