| Affiliation: | 1. Centre for Research in Development, Social and Environment (SEEDS), Faculty of Social Sciences and Humanities, Universiti Kebangsaan Malaysia, 43650 UKM Bangi, Malaysia;2. Department of Occupational Safety and Health Malaysia, Ministry of Human Resources, Government Administrative Centre, 62530 Putrajaya, Malaysia;1. School of Mathematical Science, Heilongjiang University, Harbin 150080, PR China;2. Department of Applied Mathematics, University of Western Ontario, London, Ontario, Canada, N6A 5B7;3. College of Mathematics and Statistics, Central South University, Changsha, Hunan 410083, PR China |
