# What is Neural networks: Definition and 41 Discussions

A neural network is a network or circuit of neurons, or in a modern sense, an artificial neural network, composed of artificial neurons or nodes. Thus a neural network is either a biological neural network, made up of biological neurons, or an artificial neural network, for solving artificial intelligence (AI) problems. The connections of the biological neuron are modeled as weights. A positive weight reflects an excitatory connection, while negative values mean inhibitory connections. All inputs are modified by a weight and summed. This activity is referred to as a linear combination. Finally, an activation function controls the amplitude of the output. For example, an acceptable range of output is usually between 0 and 1, or it could be −1 and 1.
These artificial networks may be used for predictive modeling, adaptive control and applications where they can be trained via a dataset. Self-learning resulting from experience can occur within networks, which can derive conclusions from a complex and seemingly unrelated set of information.

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1. ### Neural networks as mathematical models of intelligence

Why do almost all people not think that neural networks are the mathematical model of intelligence? I briefly explain what I understand: -A neuron is a mathematical object that takes numerical inputs from other nearby neurons, applies a nonlinear function (combining the input with numbers...
2. ### Mathematica Neural networks in Wolfram Mathematica

Hello, I have a question about the use of functions and overall creation of neural networks in the Wolfram Mathematica (WM) program. I wonder if it is realistic to make meaningful neural networks usable at least partially for scientific research in WM? By scientific research, I do not mean the...
3. ### MHB Neural Networks : Which stock has the biggest increase ?

Hey! 😊 On 20.06.2022 we have 1 million dollars for 10 days, so until 30.06.2022, and we want to increase the capital through shares. (The data of the shares can be found on finance.yahoo.com) So we want to check which stock has the biggest increase in this period. So we have to use the...
4. ### Python Input error for LSTM neural network

Hi everyone, I have to classify a DNA sequence with a LSTM neural network but I have a problem with the inputs shame. Both the sequence and the class are encoded with One Hot Encoding and my code is this: import pandas as pd import numpy as np data = pd.read_csv('splice.data', header = None)...
5. ### Python Understanding Graph Neural Networks (GNNs) Tutorials & Examples

I've been reading various articles on Graph Neural Networks (GNNs) for the last month or so. In particular, I have been focusing on the tutorials in A Blitz Introduction to DGL. I made it through all of the tutorials OK but I'm having trouble understanding certain aspects of GNNs. I'm also...

I am from Nepal and instead of asking us code, these are types of questions that are asked in our country examination system. IDK what's their purpose. But some of them are badly hard as there are not many examples about it in textbook(In Nepal we can't get the textbook reference that the...
7. ### How can I implement a multi-task deep learning neural network?

I have 3 classes (A, B, and C). I have 6 features: train_x = [[ 6.442 6.338 7.027 8.789 10.009 12.566] [ 6.338 7.027 5.338 10.009 8.122 11.217] [ 7.027 5.338 5.335 8.122 5.537 6.408] [ 5.338 5.335 5.659 5.537 5.241 7.043]] These features...
8. ### Understanding Convolutional Neural Networks with CNNs

Hello, I have been learning about convolutional neural networks (CNNs) recently and wonder if I could get some help with a specific question: Assume we start with an input grayscale image having size NxN pixels. The image is passed to the 1st convolutional layer which has 3 filters (kernels) of...
9. ### Prob/Stats Any good math-theory-focused books on neural networks and data science?

Hi. I'm looking for books on data science, preferably leaning towards neural networks, that focus on mathematical rigor. For example, theorems on optimization, minimum number of layers to accomplish a task efficiently, etc. Most books I've seen seem to hand wave this stuff. Anyone know any juicy...
10. ### Thoughts on neural networks "discovering" physical concepts

(sorry i post this here now because i didn't know about this sub forum earlier) I came across an interesting paper from which I'll quote parts of the intro: and the conclusion: obviously the authors are more competent in Physics than I am - so are most PF member. what are your opinions on...
11. ### Thoughts on neural networks "discovering" physical concepts

I came across an interesting paper from which I'll quote parts of the intro: and the conclusion: obviously the authors are more competent in Physics than I am - so are most PF member. what are your opinions on this? can the work of these authors "discover" physical laws in any way or is the...
12. ### Applied Maths of Neural Networks -- books and papers?

Does anyone know any good up to date books on the mathematics of neural networks? If you know any good research papers that would be cool too. I've read through "Intro to the theory of neural computation" by John Hertz but it's a 1991 book. I'm looking for generalized theorems on...
13. ### [Neural Networks] Classification of a sick brain

Hi, i have a dataset with MRI of patients with a specific disease that affects the brain and another dataset with MRI of healthy patients. I want to create a classifier (using neural networks) to classify if the MRI of a new patient show the presence of the ill or not. First of all, i...
14. ### Neural Networks Question about the Hebbs and Delta Rule

Good afternoon, I am currently working on Neural Networks and I am reading an introduction by Jeff Heaton (Neural Networks in Java). Now there are two tasks there whose solutions interest me. The first task is about applying the Hebbs rule. In the book it is given wrong because of a typo but I...
15. ### Extending Neural Networks to higher dimensions (article)

Neural networks have come a long way since I first took a course, 25 years ago. Now that I'm in the Online Masters in Analytics program at Georgia Tech, I see these topics come up often. I found the following article an interesting read...
16. ### Resource recommendations for machine learning

I am planing to change my field (in PhD) and learn Machine Learning to differentiate different phases of strongly correlated matter. I learned Monte Carlo method in my MS and have intermediate level knowledge of topological insulators. Before completely getting into Machine Learning, I want to...

18. ### Programs Diploma thesis - Neural Network Application in Physical Problems

Hello everybody. I am currently on my last year of Computational Physics education. More and more I am interested in Machine Learning and Neural Network. Time has come for me to choose diploma work thesis, so I am searching for interesting ideas where I can merge my interest in neural networks...
19. ### Logic as a dynamical system?

This thread is a shoot-off from this thread. Assuming some relation between human language and logical reasoning, how would this relate, let's say, to the arrival and evolution of logic in human and animal psychology? I would presume that some logic, for example classical logic, can be more or...
20. ### Neural Networks -- using the NN classifier as the fitness function

Let's say you've trained a neural network and it can classify cat images with good (90%) accuracy. Now let's say you use a genetic algorithm and start 'breeding' images together using the NN classifier as the fitness function. Will you eventually start generating pictures that look like cats?
21. ### Neural networks - uses in Physics and Astrophysics?

Hello, I'm not very familiar with neural networks, but it seems very interesting. I would like to ask how may I use it in physics, especially in astrophysics? I guess for some data mining? But could anyone show some concrete example of what it can do with data? Or if there is anything else...
22. ### I Neural Networks vs Traditional Numerical Methods

As neural networks are 'universal approximators' for nonlinear functions, in general how do they perform in comparison to traditional numerical methods for nonlinear PDEs? Just googling, I can find papers on applications to Navier Stokes and other problems, but I don't really have the...
23. ### Conditional Digital Feedback; is it a good Idea? (Neural Networks)

In this example: The input multiplier to the artificial neural network, at the bottom of the screen, for each note is determined by an output of an Expectation Maxamazation sequence that converges after ten iterations with input of the artificial neural network's output above a threshhold...
24. ### Other Neural networks and genetic algorithms

Hi. First of all, I am a beginner when it comes to NN and GA. I have a good enough math background though. Could anyone suggest me a good book that covers these topics in an intermediate level? Obviously a very in-depth coverage is hard to expect but I would like something more than a few pages...
25. ### Neural networks and the derivatives of the cost function

Hello. I need some guidance on the derivation of the derivatives of the quadratic cost function (CF) in an artificial neural network. I can derive the equations for the forward propagation with no trouble but when it comes to finding the derivative of the CF with respect to the weight matrix...
26. ### Prob/Stats What Are the Best Resources for Learning About Neural Networks?

Hello, Can you recommend me a book on neural networks, for a beginner in this area? I would like a book that explains the mathematics behind NN's, while still going into computational matters in a package like Matlab. My background is Physics/Maths in Bsc level. Thanks.
27. ### Can artificial intelligence create music?

Hi What approach should I take if I want to try this with music? I know the mathematics that are needed to learn neural networks (from what I have read on websites like Coursera). Also, I know basic scientific programming with Python. I am willing to spend time to learn how to make the...
28. ### Alzheimer's disease in neural networks

After watching "Still Alice"(starring Juliane Moore) which is about an Alzheimer's patient, I started thinking about this disease a little bit and suddenly it occurred to me that its plausible to expect seeing such an effect in neural networks too. I mean, imagine you have a neural network that...
29. ### Application of Artificial Neural Networks to Business Problems

Hello everyone! Searching for applications of artificial neural networks (ANNs) to real world problems, all I found were applications to computer science problems (e.g. face recognition, OCR, automated control of systems and machines etc.) and some very experimental works (e.g., crime forecast...
30. ### Classification Trees vs Neural Networks

Homework Statement Hi there, I was wondering if anyone out there was familiar with image classification algorithms. I have been creating histograms of pixel intensity distributions. For example, suppose I have 100 images of a tiger and 100 images of a lion. I create 100 histograms using...
31. ### Where Can I Learn About Artificial Neural Networks?

Hi, I am a very experienced programmer in C & C++. I want to learn about Artificial Neural Networks. Can someone recommend good books or websites?
32. ### Nonlocal correlations between separated neural networks

I came across this link: http://spie.org/x648.html?product_id=540785 Paper abstract: It was published in a journal called "Quantum Information and Computation II". I checked the accepted journal list of physicsforums (this one http://www.thomsonscientific.com/cgi...cgi?PC=MASTER ) and in...
33. ### Understanding Mean Squared Error in Neural Networks

In neural network the learning algorithm ends when the mean squared error value is less than or equal to a value we have precised. But i don't understand why we are comparing with the mean squared error and not the mean error? What does the mean squared error represent?
34. ### Building Neural Networks with C++

Hello again, Im trying to build a neural network using C++. Has anyone had a go? I think the potential implications are really interesting and would like to hear about how people might have implemented them. Another general one for anyone.
35. ### Unraveling the Mystery of "Neural Networks"

Can anyone explain to me what this "neural network" nonsense is all about? Everyone and their mother is doing research in this area, but nobody seems to know what "neural networks" are or why they would be useful. It sounds like pure hype to me.
36. ### How Can Artificial Neural Networks Enhance Radar Image Classification?

Hi Members I need to do PhD research on application of artificial neural networks in image classification (radar images), could someone please advive on where I can find the relevant and useful information: eg books, contacts, advisable University for one to enroll for PhD studies, papers etc...
37. ### Medical Exploring Virtual and Biological Neural Networks

I'm a novice here..but in virtual neural networks, does adding more virtual neurons improve the performance of the network in terms of recognizing patterns? Has this been experimentally verified anywhere? Can you then make an analogy that the same would happen in a biological neural network? Or...
38. ### Medical Modelling Memory Consolidation using Neural Networks

Hi guys, If there's anyone out there who has knowledge in this area, I'm seeking to find out how to model memory consolidation using neural networks. I was thinking of using a Hopfield network to train another Hopfield network. The first network would represent the hippocampus, and the...
39. ### Medical Where can I post about neural networks?

Is there any place to put up posts on neural networks? _____________________________________________________ Don't be fooled by the apparent humanity of this poster. He is really a computer pretending to be goat. A very smart goat...
40. ### Do Neural Networks Operate as Software or Hardware?

Are artificial neural networks emulated on a traditional computer, or do they have a processor of artificial neurons? That is, is a neural network a piece of software or hardware?
41. ### Basic question on neural networks

the ouput nodes are a threshold function of a linear combination of inputs from the previous layer; in a single layered artificial neural network, the output is a linear combination of the input and if the ann has a n_1-n_2-...-n_j-n_(j+1) structure then the n_(j+1) output layers are all a...