TA Engineering (General). Civil engineering (General) TH Building construction 28 HD28 Management. Industrial Management 22 TD Environmental technology. Sanitary engineering 19 TC Hydraulic engineering. Ocean engineering 16 TE Highway engineering. Roads and pavements 13 GE Environmental Sciences 11 QA76 Computer software 8 T Technology (General) 8 HE Transportation and Communications 7 HD Industries. Land use. Labor 6 HD61 Risk Management 3 G Geography (General) 2 NA Architecture 2 QA75 Electronic computers. Computer science 2 TG Bridge engineering 2 TK Electrical engineering. Electronics Nuclear engineering 2 TP Chemical technology 2 H Social Sciences (General) 1 HJ Public Finance 1 K Law (General) 1 Q Science (General) 1 QD Chemistry 1 QE Geology 1 TS Manufactures 1 Unspecified 1