VTCalcs is a vocal tract model written by Dr. Shinji Maeda. It was originally available for DOS only. This Matlab version can be compiled and run on any platform supported by Mathworks. In addition, a newer version of the synthesizer is available (VTsynth). This synthesizer is used in VTCalcs, but has to be compiled separately from the mex files in VTcalcs.
The above zip files contain both Windows and Linux mex files. The mex file from VTsynth has already been put at the appropriate location inside the VTCalcs distribution. However, if you want to compile vtsynth you need to download the VTsynth.zip file. Also, the files are a mixture of C and C++ code and the compiler has to be changed to g++ on Linux to compile correctly. On VC.Net it compiles without a problem.