QC Physics 28 TK Electrical engineering. Electronics Nuclear engineering 21 HE Transportation and Communications 4 TP Chemical technology 2 Chemicals 1 Detectors. Sensors. Sensor networks 1 Electric apparatus and materials. Electric circuits. Electric networks 1 Fiber optics 1 G70.212-70.215 Geographic information system 1 General special. Including optical illusion and visual perception 1 General special. Methodology 1 General works 1 LB Theory and practice of education 1 Physical optics 1 Polymers and polymer manufacture 1 Q Science (General) 1 QA75 Electronic computers. Computer science 1 QC1 Physics (General) 1 QD Chemistry 1 QH301 Biology 1 Qualities of water. Water quality 1 T58.5-58.64 Information technology 1 TA Engineering (General). Civil engineering (General) 1 Teaching (Principles and practice) 1 Unspecified 1 Water supply for domestic and industrial purposes 1