ISO/IEC TR 24372:2021

TECHNICAL ISO/IEC TR
REPORT 24372
First edition
2021-12
Information technology — Artificial
intelligence (AI) — Overview of
computational approaches for AI
systems
Reference number
© ISO/IEC 2021
© ISO/IEC 2021
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© ISO/IEC 2021 – All rights reserved

Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 General . 3
6 Main characteristics of AI systems . .5
6.1 General . 5
6.2 Typical characteristics of AI systems . 6
6.2.1 Adaptable . 6
6.2.2 Constructive . 6
6.2.3 Coordinated . 6
6.2.4 Dynamic . 6
6.2.5 Explainable . 6
6.2.6 Discriminative or generative . 6
6.2.7 Introspective . . 6
6.2.8 Trained or trainable. 7
6.2.9 Accommodating various data . 7
6.3 Computational characteristics of AI systems . 7
6.3.1 Data-based or knowledge-based . 7
6.3.2 Infrastructure-based. 7
6.3.3 Algorithm-dependent . 8
6.3.4 Multi-step or end-to-end learning-based . 9
7 Types of AI computational approaches . 9
7.1 General . 9
7.2 Knowledge-driven approaches . 10
7.3 Data-driven approaches . 10
8 Selected algorithms and approaches used in AI systems .11
8.1 General . 11
8.2 Knowledge engineering and representation . 11
8.2.1 General . 11
8.2.2 Ontology .12
8.2.3 Knowledge graph .12
8.2.4 Semantic web . . 14
8.3 Logic and reasoning . 14
8.3.1 General . 14
8.3.2 Inductive reasoning . 15
8.3.3 Deductive inference .15
8.3.4 Hypothetical reasoning . 16
8.3.5 Bayesian inference . 17
8.4 Machine learning . 18
8.4.1 General . 18
8.4.2 Decision tree . 18
8.4.3 Random forest . 19
8.4.4 Linear regression .20
8.4.5 Logistic regression . 21
8.4.6 K-nearest neighbour . 21
8.4.7 Naïve Bayes . 22
8.4.8 Feedforward neural network. 22
8.4.9 Recurrent neural network . 23
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© ISO/IEC 2021 – All rights reserved

8.4.10 Long short-term memory network. 24
8.4.11 Convolutional neural network . 25
8.4.12 Generative adversarial network . 26
8.4.13 Transfer learning . 27
8.4.14 Bidirectional encoder representations from transformers . 27
8.4.15 XLNet .28
8.5 Metaheuristics .29
8.5.1 General .29
8.5.2 Genetic algorithms .29
Bibliography .31
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© ISO/IEC 2021 – All rights reserved

Foreword
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are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria
needed for the different types of document should be noted. This document was drafted in
accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives or
www.iec.ch/members_experts/refdocs).
Attention is drawn to the possibility that some of the elements of this document may be the subject
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This document was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 42, Artificial intelligence.
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