[1] School of Economics and Management, Beijing University of Technology, Beijing,100022, China
[2] Faculty of Commerce, Damietta University, Damietta,22052, Egypt
[3] Faculty of Economics and Political Science, Cairo University, Giza,12613, Egypt
[4] Badr Petroleum Company, Cairo,5958, Egypt
[5] School of Engineering, University of Aberdeen King's College, Aberdeen,AB24 3FX