2018
As a practical demonstration of this capability , we printed at sea underwater pressure housings that remained sealed to 200 m water depth with functional integrated internal electronics .
 material: As; machine or equipment: underwater pressure housings; concept or principle: water depth; machine or equipment: integrated internal electronics
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: As, underwater pressure housings, water depth, integrated internal electronics 
Answer:
 material: As; machine or equipment: underwater pressure housings; concept or principle: water depth; machine or equipment: integrated internal electronics