TA Engineering (General). Civil engineering (General) 79 TK Electrical engineering. Electronics Nuclear engineering 75 TJ Mechanical engineering and machinery 46 QA75 Electronic computers. Computer science 39 TP Chemical technology 28 HD28 Management. Industrial Management 27 QA Mathematics 26 L Education (General) 19 TH Building construction 18 Q Science (General) 14 QA76 Computer software 14 T Technology (General) 14 HF Commerce 10 QD Chemistry 9 G70.212-70.215 Geographic information system 8 HD1394-1394.5 Real estate management 8 HG Finance 8 LB Theory and practice of education 8 H Social Sciences (General) 7 QC Physics 7 BP Islam. Bahaism. Theosophy, etc 6 HF5601 Accounting 6 HD Industries. Land use. Labor 5 NA Architecture 5 TD Environmental technology. Sanitary engineering 5 HB Economic Theory 4 QE Geology 4 TE Highway engineering. Roads and pavements 4 TH434-437 Quantity surveying 4 HE Transportation and Communications 3