8999
Our results , confirmed by experimental and analytical calculations , revealed that the damping performance can be significantly enhanced by the addition of only a small fraction of the soft phase .
 concept or principle: experimental; concept or principle: performance; material: be; concept or principle: fraction; concept or principle: phase
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: experimental, performance, be, fraction, phase 
Answer:
 concept or principle: experimental; concept or principle: performance; material: be; concept or principle: fraction; concept or principle: phase