Mathematical models 6 Design and construction 4 English language 4 Study and teaching 4 Analysis 3 Attitudes 3 Management 3 Testing 3 Air conditioning 2 Attitude (Psychology) 2 Banks and banking 2 Buildings 2 Case studies 2 Chinese 2 Commerce 2 Data processing 2 Earthquake effects 2 Economic aspects 2 Electric utilities 2 Expert systems (Computer science) 2 Forecasting 2 Foreign economic relations 2 High school students 2 Insulin 2 Music 2 Plasma-enhanced chemical vapor deposition 2 Primary Health Care 2 Quantum wells 2 Rating of 2 Refrigeration and refrigerating machinery 2