827
However , Van Der Klift , Koga showed that increasing the number of carbon fiber layers results in larger void areas , which had negative effect on the tensile strength .
 material: carbon fiber; concept or principle: void; process parameter: areas; machanical property: tensile strength
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:
 material: carbon fiber; concept or principle: void; process parameter: areas; machanical property: tensile strength