1. Elmergib University,Dept. mechanical engineering and industrial department,Alkhoms,Libya
2. Higher institute of science and technology-Alkhoms,Dep. mechanical engineering,Alkhoms,Libya
3. Higher institute of science and technology-Zawia,Dep. mechanical engineering,Zawia,Libya
4. Libyan authority for scientific research,Benghazi,Libya
5. Higher Institute of Refrigeration and Air Condition technologies,Sokna,Libya