878
The laser scans the powder bed , layer by layer , to form a 3D structure , as demonstrated in 18 .
 enabling technology: laser scans; machine or equipment: powder bed; concept or principle: layer by layer; concept or principle: 3D structure; material: as
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:
 enabling technology: laser scans; machine or equipment: powder bed; concept or principle: layer by layer; concept or principle: 3D structure; material: as