Artificial Intelligence II

ECE-A813 · Spring semester
Electrical & Computer Engineering Dept., University of Patras
Undergraduate 11 lectures Instructors: Konstantinos Chatzilygeroudis, Konstantinos Moustakas, Kyriakos Sgarbas

A second course in artificial intelligence focused on modern machine learning. It begins with the foundations of learning — loss functions, regularization, back-propagation and neural networks — and the optimization that makes training possible, from Newton and Gauss–Newton methods to stochastic gradient descent, momentum and Adam.

It then covers neural networks for computer vision (CNNs, attention and transformers), uncertainty quantification with Bayesian linear regression and Gaussian processes, learning probability distributions (GMMs, EM, ensembles), latent representations (PCA, factor analysis, autoencoders, VAEs), generative models such as flow matching and diffusion, and zero-order optimization: evolutionary strategies, genetic algorithms and swarm intelligence.

Slides for each lecture, grouped by teaching week.

Week 1
Lecture 1
Introduction to Machine Learning
  • Linear separation, non-linearities
  • Regularization
  • Loss functions, optimization
  • Back propagation
  • Neural Networks
  • Deep learning generic architecture
Slides
Week 2
Lecture 2
Optimization Basics
  • Intro to Optimization
  • Sufficient and Necessary Conditions
  • Newton's Method for Optimization
  • Line Search
  • Non-linear least squares (Gauss-Newton)
  • Practical Considerations
  • Why second-order methods struggle with large networks and datasets
Slides
Week 3
Lecture 3
Stochastic Gradient Descent and Training
  • First-order optimization methods
  • Stochastic gradient descent, momentum, Adam
  • Standardization, normalization, cross-validation
  • Metrics for hyper-parameter optimization
Slides
Week 4
Lecture 4
NNs for Computer Vision (Part I)
  • Convolution, Image convolution
  • CNNs in the image domain
  • Pooling, zero padding, cost functions
  • CNNs in the 3D domain
  • CNN autoencoders
  • CNNs in manifold surfaces
  • Applications and examples
Slides
Week 5
Lecture 5
NNs for Computer Vision (Part II)
  • Attention in DNN, rationale and impact
  • Attention layers modeling
  • Vision Transformers
  • 3D domain transformers
  • Applications and examples
Slides
Week 6
Lecture 6
Uncertainty Quantification and Non-Parametric Models
  • Uncertainty (epistemic vs aleatoric)
  • Bayesian Linear Regression
  • Gaussian Processes
Slides
Week 7
Lecture 7
Learning Probability Distributions
  • Gaussian Mixture Models and Expectation Maximization
  • Neural Networks that output distributions
  • Ensemble Neural Networks
  • Examples
Slides
Week 8
Lecture 8
Learning Latent Representations
  • PCA
  • Factor Analysis
  • Auto-Encoders
  • VAEs
Slides
Week 9
Lecture 9
Generative Models
  • Overview: connection to GMMs, Factor Analysis
  • Flow Matching
  • Diffusion
  • Examples
Slides
Week 10
Lecture 10
Zero-Order Optimization (Part I)
  • Black-Box optimization
  • Nelder-Mead (Simplex)
  • Simulated Annealing
  • Genetic Algorithms
Slides
Week 11
Lecture 11
Zero-Order Optimization (Part II)
  • Evolutionary Strategies
  • Swarm Intelligence: Particle Swarm Optimization
  • Ant Colony Optimization
Slides