TA Engineering (General). Civil engineering (General) 191 TE Highway engineering. Roads and pavements 65 TJ Mechanical engineering and machinery 48 TK Electrical engineering. Electronics Nuclear engineering 29 QA75 Electronic computers. Computer science 25 HE Transportation and Communications 18 T Technology (General) 14 TL Motor vehicles. Aeronautics. Astronautics 11 TP Chemical technology 10 HD28 Management. Industrial Management 9 TH Building construction 9 NA Architecture 8 G70.212-70.215 Geographic information system 7 HD Industries. Land use. Labor 7 HT101-395 Sociology, Urban 6 Q Science (General) 6 G70.39-70.6 Remote sensing 4 TD Environmental technology. Sanitary engineering 4 Unspecified 4 QA Mathematics 3 QA76 Computer software 3 TH434-437 Quantity surveying 3 G Geography (General) 2 G154.9-155.8 Travel and state. Tourism 2 GE Environmental Sciences 2 H Social Sciences (General) 2 HD1394-1394.5 Real estate management 2 L Education (General) 2 NA9000-9284 City planning 2 QE Geology 2