Optimization models 12 Optimization 9 Economics 4 Performance 4 Technology: general issues 4 Genetic algorithms 3 Optimisations 3 Optimization modeling 3 Optimized models 3 Particle swarm optimization (PSO) 3 human 3 AC-DC hybrid grid 2 AC-DC hybrid grids 2 Complex dynamic characteristics 2 Computational linguistics 2 Conjugate gradient method 2 Convergence analysis 2 Deep learning 2 Diseases 2 Efficiency 2 Engineering: general 2 Environmental technology 2 Evaluation indicators 2 Evaluation methods 2 Geography 2 Heuristic methods 2 History of engineering & technology 2 History of engineering and technology 2 Humans 2 Hyper-parameter 2