Hi, YasK:

It has been my pleasure editing your document. To answer your follow-up questions: 

(1) Comment YK5: What about test pieces molded with conventional method instead of other ones? Please look at this part that you corrected. --- Yes, you can say "four times stronger than test pieces molded using conventional methods."

(2) Ota city, the heart of precision manufacturing in Japan awarded the Most Excellent Factory Award to Nisshin Industrial Ltd. --- You can say, "The city of Ota, the heart of precision manufacturing in Japan, granted Nisshin Industrial Ltd. the Most Excellent Factory Award."

You're quite welcome; thank you!
MasterEditor