Electrical engineering 21 History of engineering and technology 18 Technology: general issues 13 Cyber Physical System 8 Embedded systems 8 Circuits & components 6 History of engineering & technology 6 cyber-physical systems 6 Computer networking and communications 5 Artificial intelligence 4 Computer networking & communications 4 Computer science 4 Computing & information technology 4 Cybe-physical systems 4 Cyber-physical systems 4 'current 3 Algorithms and data structures 3 Automatic control engineering 3 Chemistry 3 Computer architecture & logic design 3 Computer-aided design (CAD) 3 Computing and Information Technology 3 Cyber security 3 Cybersecurity 3 Databases 3 Expert systems / knowledge-based systems 3 Industry 4.0 3 Information technology industries 3 Machine learning 3 Robotics 3