Studi Komparatif Eksperimental Karakter Pembakaran Nyala Api Difusi Bahan Bakar Dimethyl Ether (DME) terhadap Liquefied Petroleum Gas (LPG) Pada Berbagai Jet Velocity = Experimentally Comparative Study on Diffusion Flame Combustion Characteristics of Dimethyl Ether (DME) and Liquefied Petroleum Gas (LPG) on Various Jet Velocity