I'm not good at English. I'm a undergraduate student. I'm interested in this research. I'm interested the simulation part but I don't know how to start. Please guiding me how to simulate method or program did they use on paper. " A Theoretical Study on Van Der Pauw Measurement Values of Inhomogeneous Compound Semiconductor Thin Films " (http://www.scirp.org/journal/PaperDownload.aspx?paperID=3261) I want to compare Inhomogeneous and homogeneous. Everyday i find how to simulate but not found correct way.