TJ Mechanical engineering and machinery 259 TA Engineering (General). Civil engineering (General) 112 TP Chemical technology 80 TK Electrical engineering. Electronics Nuclear engineering 26 QA75 Electronic computers. Computer science 16 T Technology (General) 15 TS Manufactures 14 QD Chemistry 12 HD28 Management. Industrial Management 6 QA76 Computer software 6 QH301 Biology 6 TH Building construction 6 VM Naval architecture. Shipbuilding. Marine engineering 6 QA Mathematics 5 QC Physics 5 Biomechanics 4 Force 4 Kinematics 4 LB Theory and practice of education 4 NA Architecture 4 Sprinting 4 Unspecified 4 Additive manufacturing 3 HE Transportation and Communications 3 Knee 3 Performance 3 Physiology 3 Power 3 Q Science (General) 3 QE Geology 3