Compression ratio: It is the ratio of the cylinder volume above the piston at BDC to the volume above the piston at TDC. Related posts: Personnel Management Operative Functions Administrative Role of PM Competency HR Management Role Change Personnel Policies Personnel Procedures Appealed Policies Implied Policies Specific Policies Personnel records Research Pure research Personnel research Attitude or Opinion Survey Turnover Secondary research Applied research Personnel audit Read more articles Previous PostCommon rail injection Next PostCondenser