TP Chemical technology 35 TK Electrical engineering. Electronics Nuclear engineering 16 TA Engineering (General). Civil engineering (General) 13 QC Physics 8 QD Chemistry 7 TJ Mechanical engineering and machinery 6 Q Science (General) 5 QA75 Electronic computers. Computer science 5 G70.39-70.6 Remote sensing 4 QA Mathematics 4 T Technology (General) 4 G70.212-70.215 Geographic information system 3 NA Architecture 3 T58.5-58.64 Information technology 3 TD Environmental technology. Sanitary engineering 3 HF Commerce 2 LB Theory and practice of education 2 TH Building construction 2 BP Islam. Bahaism. Theosophy, etc 1 G109.5 Global Positioning System 1 GE Environmental Sciences 1 HA Statistics 1 HD Industries. Land use. Labor 1 HD1394-1394.5 Real estate management 1 HD28 Management. Industrial Management 1 HE Transportation and Communications 1 QE Geology 1 QH301 Biology 1 TH434-437 Quantity surveying 1 Unspecified 1