T Technology (General) TA Engineering (General). Civil engineering (General) 28 Q Science (General) 25 TK Electrical engineering. Electronics Nuclear engineering 24 TJ Mechanical engineering and machinery 20 TP Chemical technology 10 T58.5-58.64 Information technology 7 H Social Sciences (General) 6 QA75 Electronic computers. Computer science 6 QA76 Computer software 6 G Geography (General) 5 L Education (General) 5 QA Mathematics 4 T58.6-58.62 Management information systems 4 Technological innovations 4 HD28 Management. Industrial Management 3 TD Environmental technology. Sanitary engineering 3 TH Building construction 3 TR Photography 3 Technological change 3 Industrial engineering. Management engineering 2 Information technology. Information systems 2 LB Theory and practice of education 2 LB2300 Higher Education 2 QC Physics 2 Applied mathematics. Quantitative methods 1 BF Psychology 1 BP Islam. Bahaism. Theosophy, etc 1 Business communication. Including business report writing, business correspondence 1 Creative ability in technology 1