TK Electrical engineering. Electronics Nuclear engineering 161 Technology: general issues 151 History of engineering and technology 121 QA Mathematics 86 Research & information: general 76 human 73 TA Engineering (General). Civil engineering (General) 65 Humans 61 Nonlinear equations 59 article 54 TJ Mechanical engineering and machinery 50 History of engineering & technology 45 Forecasting 35 Research and information: general 35 adult 34 male 34 Mathematics & science 33 Q Science (General) 33 Nonlinear optics 32 female 32 Article 31 physiology 31 nonlinear system 30 Controllers 28 Physics 28 QC Physics 28 Nonlinear analysis 25 controlled study 25 Information technology industries 23 Neural networks 23