Artificial neural network
lastmod 2026-10-11created 2014-10-3116 edits
An artificial neural network is an interconnected group of nodes, similar to the vast network of neurons in a brain. In the figure above, each circular node represents an artificial neuron, and an arrow represents a connection from the output of one neuron to the input of another.
An artificial neural network (neural network) is a mathematical model that aims to express some characteristics of brain function through computer simulation.
An artificial neural network refers broadly to any model in which artificial neurons (nodes), which form a network through synaptic connections, change the strength of those synaptic connections through training and thereby gain the ability to solve problems. In a narrow sense it is sometimes used to mean a multilayer perceptron trained with error backpropagation, but this is an incorrect usage; artificial neural networks are not limited to this.
Artificial neural networks include supervised learning, in which the network is optimized for a problem through the input of a teacher signal (correct answer), and unsupervised learning, which does not need a teacher signal. Supervised learning is used when there is a clear answer, and unsupervised learning is used for data clustering. As a result, in order to reduce dimensions, many of them can obtain good answers with relatively little computation for problems that are not linearly separable, on multidimensional data such as images or statistics. For that reason, they are applied in various fields such as pattern recognition and data mining.
Artificial neural networks can be built using specialized computers, but most are implemented by application software on ordinary computers.
Background
Research into the human central nervous system inspired the concept of neural networks. In artificial neural networks, artificial neurons are connected to each other to form a network that mimics biological neural networks.
There is no single formal definition of what an artificial neural network is. However, a set of statistical models is called neural (Neural) if it has the following characteristics.
- It consists of a set of adjustable weights, that is, numerical parameters that can be adjusted by a learning algorithm.
- It can infer non-linear functions of its inputs.
The adjustable weights represent the connection strengths between neurons, and they are activated during training or prediction.
Neural networks resemble biological neural networks in that functions are performed in parallel or collectively by the units, rather than as subtasks assigned to the various units. The word 'neural network' usually refers to models used in statistics, cognitive psychology, and artificial intelligence. Neural network models that emulate the central nervous system are part of theoretical neuroscience and computational neuroscience.
About this
An artificial neural network uses a Combination function, which combines the input variables, and an Activation function, which combines and transforms the input information. The Combination function turns the pieces of input information into a single piece of information, most commonly using a weighted average, and the Activation function is a function that passes the combined value of the input information to the output layer or hidden layer, converting the combined value of the input information into a value within a certain range.
Category
- Perceptron
- Adaline (Adaptive Linear Neuron)
- Madaline (Many Adaline)
- Has an input layer, an output layer, and one or more hidden layers (Hidden layer).
- The training method is as follows.
- Present the input data to each unit of the input layer.
- This signal is transformed at each unit and passed to the intermediate layer.
- Finally, the result comes out at the output layer.
- Compare the output value with the desired output value and adjust the connection strengths in the direction that reduces the difference.
- Backpropagation
- Associative Memory
- Competitive Learning
- Each neuron calculates how close its connection-strength vector is to the input vector. The neurons then compete with each other to be granted the privilege of learning, and the neuron with the shortest distance wins.
- Self-organizing Feature Maps
- A combination of Kohonen's self-organizing map and Grossberg's outstar algorithm.
- A pattern recognition multilayer neural network model based on the way the human visual system recognizes things
- A pattern recognition model developed by Fukushima (K, Fukushima) in 1975; a multilayer neural network model that performs competitive learning.
- SONN (Self-Organizing Neural Network)
- When the connection strengths between neurons are adjusted, each connection strength is adjusted according to its fuzzy similarity with the input vector.
Table of Machine learning
Documentation
Bayesian probability
- Bayesian Reasoning and Machine Learning
- http://web4.cs.ucl.ac.uk/staff/D.Barber/pmwiki/pmwiki.php?n=Brml.Online
- http://web4.cs.ucl.ac.uk/staff/D.Barber/textbook/020217.pdf
-
020217_-_Bayesian_Reasoning_and_Machine_Learning.pdf
Deep learning
- ImageNet Classification with Deep Convolutional Neural Networks (AlexNet)
- http://www.cs.toronto.edu/~fritz/absps/imagenet.pdf
- http://papers.nips.cc/paper/4824-imagenet-classification-with-deep-convolutional-neural-networks.pdf
-
ImageNet_Classification_with_Deep_Convolutional_Neural_Networks.pdf - [Korean translation] ImageNet classification using deep convolutional neural networks
-
ImageNet_Classification_with_Deep_Convolutional_Neural_Networks_-_ko.pdf
- Going deeper with convolutions (GoogleNet)
- http://arxiv.org/pdf/1409.4842v1.pdf
-
Going_deeper_with_convolutions.pdf - Translation: GoogleNet
- Special feature article: Deep Hypernetwork models (Seoul National University/Byoung-Tak Zhang)
-
Deep_Hypernetwork_models_201508.pdf
- [Mocrosoft] Deep Residual Learning for Image Recognition (Winner ILSVRC2015)
-
Deep_Residual_Learning_for_Image_Recognition(Winner_ILSVRC2015)_Microsoft.pdf
- [Microsoft] Fast R-CNN, Towards Real-Time Object Detection with Region Proposal Networks (Winner ILSVR2015)
-
Fast_R-CNN,Towards_Real-Time_Object_Detection_with_Region_Proposal_Networks(Winner_ILSVR2015)_Microsoft.pdf
- Learning Deconvolution Network for Semantic Segmentation
- http://cvlab.postech.ac.kr/research/deconvnet/
- Deep EXpectation of apparent age from a single image
- https://data.vision.ee.ethz.ch/cvl/rrothe/imdb-wiki/
- Inside-Outside Net: Detecting Objects in Context with Skip Pooling and Recurrent Neural Networks.
-
Inside_outside_net_detecting_objects_in_context_with_skip_pooling_and_recurrent_neural_networks_2015.pdf - A paper on Small Object detection methods.
- Cho Dae-hyup's blog - Understanding deep learning and TensorFlow for those who gave up on math
- http://bcho.tistory.com/1208
-
Machine_learning_ebooks_-_Machine_learning_for_those_who_abandon_math.pdf
- Densely Connected Convolutional Networks (DenseNets)
- Deep learning CVPR2017 Best Paper Award
- Deep Learning Interviews book: Hundreds of fully solved job interview questions from a wide range of key topics in AI.
- Deep learning interview book
- A collection of practical questions and solutions for master's/PhD students and job seekers learning machine learning
- A printed copy can also be purchased, but the full PDF is freely available
- [Recommended] "Key AI Glossary You Must Know in the AI Era, Examined Through 2025 AI Trends and Issues" published by NIA (National Information Society Agency)
- Key glossary you must know in the AI era (168p PDF) | GeekNews
- https://www.nia.or.kr/site/nia_kor/ex/bbs/View.do?cbIdx=82618&bcIdx=28928&parentSeq=28928
-
Nia.or.kr_-ai-_2025_terms.pdf
- There Will Be a Scientific Theory of Deep Learning
- There will be a scientific theory of deep learning. | GeekNews
- There Will Be a Scientific Theory of Deep Learning
- A paper arguing that a scientific theory characterizing key properties of deep learning, such as the training process, hidden representations, final weights, and performance, is taking shape
- Presents five research threads (interpretable idealized settings, tractable limits, simple mathematical laws, hyperparameter theory, universal behaviors) as its core evidence
Tutorials
- Getting Started with Deep Learning Properly (author Takayuki Okatani / translator Shim Hyo-seop)
-
Deep_Learning_-Takayuki_Okatani-2015-_sample.pdf
- Introductory Guide to Machine Learning - IDG Deep Dive
- http://www.itworld.co.kr/techlibrary/97428
-
IDG_DeepDive_Machine_learning-20160113.pdf
- Understanding Deep Learning (unpublished; 2016-08-22 ver)
-
Understanding_deep_learning_0822.pdf
- Fundamental of Reinforcement Learning
- https://www.gitbook.com/book/dnddnjs/rl/details
-
Fundamental_of_Reinforcement_Learning.pdf - MODULABS - Fundamentals of reinforcement learning
- Deep Learning Papers Reading Roadmap (deep learning paper roadmap)
- https://github.com/songrotek/Deep-Learning-Papers-Reading-Roadmap/blob/master/README.md
-
Deep_Learning_Papers_Reading_Roadmap.md.zip
- [Recommended] Machine Learning-based Web Exception Detection (reference site related to the Financial Security Institute project!)
- https://cloudfocus.aliyun.com/Machine-Learning-based-Web-Exception-Detection-89782?spm=a2c1b.a2c1b4.a2c1b4.16.ZSQoEd
-
Machine_Learning-based_Web_Exception_Detection_-Insights_and_Trends-_Alibaba_Cloud_Focus.pdf
- Machine learning basics parts 1–57 (Odds-and-ends exploration - Chamstudy ePaiai : Naver Blog)
- http://sams.epaiai.com/220498694383
- Microsoft releases ML for Beginners course
- A 12-week, 24-lesson curriculum made by the MS Azure Clouds Advocates team
- A classic machine learning course using Scikit-learn (deep learning will come as a separate AI course)
- https://github.com/microsoft/ML-For-Beginners
- CS146S: The Modern Software Developer (Korean) | GeekNews
- [Original] CS146S Korean Edition | The Modern Software Developer
- The official Korean version of Stanford's CS146S course
Compress model
- Deep Compression and EIE - Deep Neural Network Model Compression and Efficient Inference Engine
-
Deep_compression_and_EIE_PPT.pdf
- Learning bothWeights and Connections for Efficient Neural Networks
-
Learning_both_weights_and_connections_for_efficient_neural_networks_2015.pdf
Convolutional neural network
- A CNN Presentation using Reveal.js.
- Author - me
-
Reveal-ml.tar.gz
- Gradient-Based Learning Applied to Document Recognition
- http://yann.lecun.com/exdb/publis/pdf/lecun-01a.pdf
-
Gradient-Based_Learning_Applied_to_Document_Recognition.pdf
- Visualizing and Understanding Convolutional Neural Networks
- http://arxiv.org/abs/1311.2901
-
1311.2901v3.pdf
- Compressing CNN for Mobile Device (Samsung) - the need for CNN model compression etc ...
- [http://mlcenter.postech.ac.kr/files/attach/workshop_fall_2015/삼성전자_김용덕_박사.pdf](http://mlcenter.postech.ac.kr/files/attach/workshop_fall_2015/삼성전자_김용덕_박사.pdf)
-
Samsung_-_Compressing_CNN_for_Mobile_Device.pdf
- Using Filter Banks in Convolutional Neural Networks for Texture Classification
- https://arxiv.org/abs/1601.02919
Deep belief network
- The Applications of Deep Learning on Traffic Identification
-
Us-15-Wang-The-Applications-Of-Deep-Learning-On-Traffic-Identification-wp.pdf - https://www.blackhat.com/docs/us-15/materials/us-15-Wang-The-Applications-Of-Deep-Learning-On-Traffic-Identification-wp.pdf
Deconvolution neural network
- Learning Deconvolution Network for Semantic Segmentation
- http://cvlab.postech.ac.kr/research/deconvnet/
- https://arxiv.org/abs/1505.04366
-
1505.04366.pdf
Segmentation
- Learning to Segment (Facebook Research)
- https://research.fb.com/learning-to-segment/
- DeepMask+SharpMask as well as MultiPathNet.
- Recurrent Instance Segmentation
- https://arxiv.org/abs/1511.08250
-
1511.08250.pdf - Slideshare - Single Shot MultiBox Detector and Recurrent Instance Segmentation
- vid2vid
- https://github.com/NVIDIA/vid2vid
- Pytorch implementation for high-resolution (e.g., 2048x1024) photorealistic video-to-video translation.
- It can be used for turning semantic label maps into photo-realistic videos, synthesizing people talking from edge maps, or generating human motions from poses.
Fire Detection
Organized under Fire Detection#Deep learning based.
Background subtraction
Organized under Background subtraction#Deep learning based.
LSTM
Organized under Long short-term memory.
Learning
- Siamese Neural Networks for One-Shot Image Recognition
- https://jayhey.github.io/deep%20learning/2018/02/06/saimese_network/
- Training a network in deep learning requires a very large amount of training data. One-shot learning overcomes this drawback by training the network so that it can classify even with only one image per label.
NVIDIA AI Developer Newsletter
- [Recommended] AI Can Transform Anyone Into a Professional Dancer
- https://news.developer.nvidia.com/ai-can-transform-anyone-into-a-professional-dancer/
- https://arxiv.org/abs/1808.07371
- Transforming Standard Video Into Slow Motion with AI
- https://news.developer.nvidia.com/transforming-standard-video-into-slow-motion-with-ai/
- NVIDIA SPLATNet Research Paper Wins a Major CVPR 2018 Award
- https://news.developer.nvidia.com/nvidia-splatnet-research-paper-wins-a-major-cvpr-2018-award/
- AI Learns to Play Dota 2 with Human Precision
- https://news.developer.nvidia.com/ai-learns-to-play-dota-2-with-human-precision/
- [Recommended] This AI Can Automatically Remove the Background from a Photo
- https://news.developer.nvidia.com/this-ai-can-automatically-remove-the-background-from-a-photo/
- NVDLA Deep Learning Inference Compiler is Now Open Source
- https://devblogs.nvidia.com/nvdla/
Nature
- Deep learning of aftershock patterns following large earthquakes
- https://www.reddit.com/r/MachineLearning/comments/9bo9i9/r_deep_learning_of_aftershock_patterns_following/
- https://www.nature.com/articles/s41586-018-0438-y
- https://drive.google.com/file/d/1DSqLgFZLuNJXNi2dyyP_ToIGHj94raWX/view
Cancer
- Deep Neural Networks Improve Radiologists’ Performance in Breast Cancer Screening
- https://medium.com/@jasonphang/deep-neural-networks-improve-radiologists-performance-in-breast-cancer-screening-565eb2bd3c9f
Text Generation
See Text Generation.
Favorite site
Machine learning
- Wikipedia (en) description of machine learning
- Machine Learning - OpenCV machine learning algorithms 2
- UNIVERSITY OF OXFORD: COMPUTER SCIENCE: Machine Learning: 2014-2015 Course materials (Oxford University machine learning course materials and videos)
- History of machine learning 1
- History of machine learning 2
- Parameter tuning and training
- Team AI Korea : We do Artificial Intelligence
- [Recommended] Mad for Simplicity - Enginius/Machine Learning (lots of machine learning content, neatly organized)
- [Recommended] HUB-AI - AI STUDY (lots of AI study materials)
- How a working programmer who gave up on math can start studying machine learning
- A look at basic math for machine learning by mingrammer
- [Recommended] Browse state-of-the-art
- [Recommended] Artificial Intelligence (AI) & Machine Learning (ML) Dictionary - WikiDocs
E-book
- [Recommended] 15 recommended free textbooks on robotics and machine learning/artificial intelligence
- The Element of Statistical Learning: Data Mining, Inference, and Prediction – T. Hastie, R. Tibshirani, J. Friedman (2009)
- Introduction to Machine Learning – A. Shashua (2008)
- Deep Learning – An MIT Press book in preparation - Y. Bengio (2015)
- Learning Deep Architectures for AI – Y. Bengio (2009)
- Gaussian Process for Machine Learning – C. Rasmussen, C. Williams
- Reinforcement Learning – C. Weber, M. Elshaw, N. Mayer (2008)
- Reinforcement Learning: An Introduction – R. Sutton, A. Barto (1998)
- Bayesian Reasoning and Machine Learning – D. Barber (2014)
Data analysis
Artificial neural network
- Wikipedia (en) description of artificial neural networks
- Neural networks - Data Mining 3
- Sigmoid Function of the Artificial neural network 4
- [Recommended] Neural network theory : Oh Chang-seok 5 (includes explanations of several Activation functions)
- MLWiki (will mainly explain neural networks, including Deep Learning)
- Study/Artificial Intelligence: Artificial Neural Network
- A Neural Network in 11 lines of Python (Part 1) (writes a Neural Network directly in Python code)
Convolutional neural network
- Wikipedia (en) description of CNN
- LeNet-5, convolutional neural networks
- TensorFlow - (5) MNIST - CNN
- [Recommended] VGG Convolutional Neural Networks Practical 6 (an example that works through CNN step by step)
- Convolutional Neural Networks (formulas for Convolutional, Max-Pooling, Fully-Connected, and Backpropagation)
- SlideShare: Backpropagation in Convolutional Neural Network
- Songorithm ML : Middle Learning = Shallow + Deep Machine Learning
Segmentation
- [Recommended] A LOOK AT IMAGE SEGMENTATION USING CNNS 10 (CNN)
Deep learning
- Wikipedia (en) description of deep learning
- Deep learning tutorial for beginners
- Korean dependency parsing using deep learning
- Deep Learning, let's take a quick look
- Welcome to Deep Learning
Deep learning libraries
- Wikipedia (en) Comparison of deep learning software
- Deep Learning Comp Sheet: Deeplearning4j vs. Torch vs. Theano vs. Caffe vs. TensorFlow
- Which Deep Learning Library should I choose?
- [Recommended] Evaluation of Deep Learning Toolkits
Andrew Ng
- [Recommended] Coursera - Machine Learning - Stanford - by Andrew Ng 1415
Machine Learning Exercises In Python
- Part 1 - Simple Linear Regression 19
- Part 2 - Multivariate Linear Regression 20
- Part 3 - Logistic Regression 21
- Part 4 - Multivariate Logistic Regression 22
- Part 5 - Neural Networks 23
- Part 6 - Support Vector Machines 24
- Part 7 - K-Means Clustering & PCA 25
- Part 8 - Anomaly Detection & Recommendation 26
Guides
- Deeplearning4j #2 example MNIST
- Classifying MNIST digits using Logistic Regression
- Deep Learning
- Samsung Software Membership: Artificial Neural Network #1 (a simple Neuron implementation in C++ code)27
- Samsung Software Membership: Artificial Neural Network #2 (a simple Feedforward neural network implementation in C++ code) 28
- Number plate recognition with Tensorflow (car license plate recognition)
- [Recommended] GPU: how much faster than CPU? 29 (compares forward time on GPU and CPU for well-known deep learning model architectures)
Tutorials
- WikiDocs - Deep Learning theory and practice (under revision)
- [Recommended] WikiDocs - Machine Learning lecture notes
- [Recommended] Gihub - 1ambda - Data Analysis 30
- UFLDL Tutorial (Unsupervised Feature Learning and Deep Learning)
- opentutorials - Machine learning
- [Recommended] GitBook - leonardoaraujosantos > Artificial Inteligence 31
- [Recommended] Other posts in the 'Machine learning_Professor Sung Kim' category
- [Recommended] 170915 Tensorflow seminar: Deep learning from theory to practice - POSTECH 32
- A page summarizing the prerequisite knowledge needed to understand Reinforcement Learning
- [Recommended] Neural Networks : Zero to Hero - coding neural network development from scratch | GeekNews
- A neural network development course made by Andrej Karpathy, former head of AI at Tesla
- Develops everything from the basics of backpropagation up to modern deep neural networks like GPT
- Language models are good for learning deep learning. Even if you later expand into areas like computer vision, most of what you learn applies immediately
- [Original] Neural Networks: Zero To Hero
- [Original] aie-book/resources.md at main · chiphuyen/aie-book
- Only the most helpful picks from the 1200+ links and 1000+ AI Github Repos that Chip Huyen referred to while writing the "AI Engineering" book
Data pool
- Fueling the Gold Rush: The Greatest Public Datasets for AI 33 (a collection of datasets for AI!)
Service
- Aifiddle - Design, Train & Share AI Models from your browser (lets you easily assemble deep learning models in the browser)
- PlayGround - Tinker With a Neural Network Right Here in Your Browser. Don’t Worry, You Can’t Break It. We Promise (the graph of data passed between the model's layers is displayed visually)
- DeepL Translate: The world's most accurate translator
- A "generate a summary of anything on the web" tool provided by the search engine Kagi
- Universal Summarizer - summarizes anything for you | GeekNews
Sample images good for use in proposals
- [https://www.google.com/imgres?imgurl=https%3A%2F%2Fd3i71xaburhd42.cloudfront.net%2F791a9a8d8fe3110985211b3256b67c0e979fdf8a%2F2-Figure1-1.png&imgrefurl=https%3A%2F%2Fwww.semanticscholar.org%2Fpaper%2FImage-Sequences-Based-Traffic-Incident-Detection-Zou-Shi%2F791a9a8d8fe3110985211b3256b67c0e979fdf8a%2Ffigure%2F0&tbnid=U1aALMVaNKcjhM&vet=10CBAQxiAoAWoXChMImOranIz17gIVAAAAAB0AAAAAECg..i&docid=jy0zapjJfnlb9M&w=564&h=426&itg=1&q=Person%20Tracking%20&client=firefox-b-d&ved=0CBAQxiAoAWoXChMImOranIz17gIVAAAAAB0AAAAAECg#imgrc=zFEtt7J5NRRniM&imgdii=IsNk3wEGRScDPM Google Image Search] - samples of car object detection at intersections
Online demo
References
-
Sigmoid_Function_of_Artificial_Neural_Network.pdf ↩
-
Machine_Learning_-_OpenCV_ML_algorithms.pdf ↩
-
S1_nn.pdf ↩
-
Sigmoid_Function_of_Artificial_Neural_Network.pdf ↩
-
Aistudy.co.kr_-_theory_oh.pdf ↩
-
VGG_Convolutional_Neural_Networks_Practical.pdf ↩
-
ConvNets_24_April.pdf ↩
-
Forward_and_Backward_Propagation_of_the_Convolutional_Layer.pdf ↩
-
The_easiest_way_to_understand_CNN_backpropagation.pdf ↩
-
A_Look_at_Image_Segmentation_using_CNNs_–_Mohit_Jain.pdf ↩
-
Artificial_Intelligence_6-Deep_Learning.pdf ↩
-
The_Devil_is_always_in_the_Details_-_Must_Know_Tips_and_Tricks_in_DNNs.pdf ↩
-
Openresearch.ai-190921.zip ↩
-
Stanford-machine_learning-andrew_ng-lectures.tar.gz ↩
-
SanghyukChun.github.io-006e2ae.tar.gz ↩
-
1ambda.github.io-19962c5.tar.gz ↩
-
Machine_Learning_Exercises_In_Python_-_Part_1.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_2.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_3.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_4.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_5.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_6.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_7.pdf ↩
-
Machine_Learning_Exercises_In_Python_-_Part_8.pdf ↩
-
Samsung_software_membership_-_Neural_network_01.pdf ↩
-
Samsung_software_membership_-_Neural_network_02.pdf ↩
-
GPU_-how_much_faster_than_CPU-_NeoBrain.pdf ↩
-
1ambda.github.io-master-5c58cab.zip ↩
-
Gitbook_-leonardoaraujosantos-_artificial-inteligence.pdf ↩
-
170915_Tensorflow_Seminar_From_Deep_Learning_Theory_to_Practice_-_POSTECH.pdf ↩
-
Fueling_the_Gold_Rush_-The_Greatest_Public_Datasets_for_AI-Startup_Grind-_Medium.pdf ↩
- Activation function
- Artificial intelligence
- Artificial neuron
- Combination function
- Computer Sciences
- Convolutional neural network
- Deep learning
- Dropout
- Feedforward neural network
- Hyperparameter
- Machine learning
- MMSegmentation
- OpenCV:SVM
- Perceptron
- Rectifier
- Sigmoid function
- Statistical classification
- Support Vector Machine