(Portland, OR)  --  A Portland man is facing 15 years behind bars for sexually exploiting children on the popular app TikTok.  A judge sentenced 33-year-old Juan Carlos Ramon yesterday to 180 months in federal prison followed by a life term of supervised release.  Ramon pleaded guilty in May to two counts of production of child pornography.  Police say he exploited two girls between the ages of ten and 13 by pretending to be a young girl on the app TikTok and encouraging the girls to imitate sexual positions and acts.