TK Electrical engineering. Electronics Nuclear engineering 262 TJ Mechanical engineering and machinery 259 TA Engineering (General). Civil engineering (General) 149 QA75 Electronic computers. Computer science 114 TP Chemical technology 101 T Technology (General) 66 QA Mathematics 51 Q Science (General) 36 HD28 Management. Industrial Management 29 QC Physics 20 QD Chemistry 16 NA Architecture 14 QA76 Computer software 14 TL Motor vehicles. Aeronautics. Astronautics 14 Unspecified 14 G70.212-70.215 Geographic information system 11 L Education (General) 11 QH Natural history 10 VM Naval architecture. Shipbuilding. Marine engineering 10 BP Islam. Bahaism. Theosophy, etc 9 H Social Sciences (General) 9 QH301 Biology 9 TH Building construction 9 LB Theory and practice of education 7 Q Science 7 HD Industries. Land use. Labor 6 R Medicine (General) 6 TC Hydraulic engineering. Ocean engineering 6 TK7885-7895 Computer engineer. Computer hardware 6 G Geography (General) 5