TA Engineering (General). Civil engineering (General) 74 TP Chemical technology 64 TJ Mechanical engineering and machinery 60 TK Electrical engineering. Electronics Nuclear engineering 57 QD Chemistry 44 HD28 Management. Industrial Management 38 TH Building construction 36 T Technology (General) 32 QA75 Electronic computers. Computer science 31 Q Science (General) 28 L Education (General) 21 QC Physics 19 K Law (General) 18 HD Industries. Land use. Labor 16 NA Architecture 15 TD Environmental technology. Sanitary engineering 13 H Social Sciences (General) 12 QA Mathematics 10 HD1394-1394.5 Real estate management 7 LB Theory and practice of education 7 QA76 Computer software 7 Q Science 6 QE Geology 6 BP Islam. Bahaism. Theosophy, etc 5 TH434-437 Quantity surveying 5 HD30.2 Knowledge management 4 HD30.213 Management information systems. Decision support systems 4 HF Commerce 4 HT Communities. Classes. Races 4 QH Natural history 4