Lecture 8: Semantic Networks and Frames

This lecture is part of the course “Foundations of Artificial Intelligence” developed by Dr. Ryan Urbanowicz in 2020 at the University of Pennsylvania’s Perelman School of Medicine. This is the first of three courses covering topics in artificial intelligence for application within the context of informatics and biomedical research. The course is divided into modules that cover (1) introductory/background materials, (2) logic, (3) other knowledge representation, (4) essentials of expert systems, (5) search, (6) uncertainty, and (7) advanced/auxiliary topics. These topics offer a global foundation for branches of AI application and research, including concepts that will later support a deeper understanding of inductive reasoning and machine learning. In a practical sense, this course focuses on how biomedical data can be organized, represented, interpreted, searched, and applied in order to derive knowledge, make decisions, and ultimately make predictions while avoiding bias. This course was assembled using content from a wide variety of textbooks, slides, and lectures by various authors and speakers on the relevant topics. Some lectures were prepared and given by guest lecturers and thus have not been posted. At the time of posting, this course is in its second year so any feedback is welcome regarding any mistakes or suggested improvements. Weblinks: http://ryanurbanowicz.com/ https://www.med.upenn.edu/urbslab/ https://github.com/UrbsLab Chapters: 0:00 Introduction 5:17 Semantic Networks 9:02 AND/OR Trees 10:15 IS/A Hierarchy 11:16 IS/Part Hierarchy 11:55 Inference Through Inheritance 13:34 More General Semantic Networks 18:48 Intersection Search 20:01 Tangled Hierarchies 24:06 Semantic Networks: Advantages 24:59 Semantic Networks: Disadvantages 26:30 Semantic Network Examples 32:15 From Semantic Networks to Frames 33:04 Frames 37:21 Converting Between Networks and Frames 38:07 Frames: Simple and Beyond 38:38 More on Slots 40:04 More on Frames 44:04 Advantages of Frames 45:03 Disadvantages of Frames 45:55 Frame Examples 46:45 Scripts 49:39 Other Semantic Network Related Representations 52:12 Conclusion