Neural Networks and Deep Learning are the two hot buzzwords used nowadays with Artificial Intelligence. The recent developments in the world of Artificial intelligence can be attributed to these two as they have played a significant role in improving the intelligence of AI.
Look around, and you will find more and more intelligent machines around. Thanks to Neural Networks and Deep Learning, jobs and capabilities that were once considered the forte of humans are now being performed by machines. Today, Machines are no longer made to eat more complex algorithms. Still, instead, they are fed to develop into an autonomous, self-teaching system capable of revolutionizing many industries.
Neural Networks and Deep Learning have lent enormous success to researchers in tasks such as image recognition, speech recognition, and finding deeper relations in data sets. Aided by the availability of massive amounts of data and computational power, machines can recognize objects, translate speech, train themselves to identify complex patterns, learn how to devise strategies, and make contingency plans in real-time.
So, how exactly does this work? Do you know that both Neutral Networks and Deep-Learning are related, in fact, to understand Deep learning, you must first understand Neural Networks? Read on to know more.
What is a Neural Network
A Neural network is a programming pattern or a set of algorithms that enables a computer to learn from observational data. A Neural network is similar to a human brain, which works by recognizing patterns. The sensory data is interpreted using a machine perception, labeling or clustering raw input. The patterns recognized are numerical, enclosed in vectors, into which the data such are images, sound, text, etc. are translated.
Think Neural Network! Think how a human brain function
As mentioned above, a neural network functions just like a human brain; it acquires all the knowledge through a learning process. After that, synaptic weights store the acquired knowledge. During the learning process, the synaptic weights of the network are reformed to achieve the desired objective.
Just like the human brain, Neural Networks work like non-linear parallel information-processing systems which rapidly perform computations such as pattern recognition and perception. As a result, these networks perform very well in areas like speech, audio and image recognition where the inputs/signals are inherently nonlinear.
In simple words, you can remember Neural Network as something which is capable of stocking knowledge like a human brain and using it to make predictions.
Structure of Neural Networks
(Image Credit: Mathworks)
Neural Networks comprise of three layers,
- Input layer,
- Hidden layer, and
- Output layer.
Each layer consists of one or more nodes, as shown in the below diagram by small circles. The lines between the nodes indicate the flow of information from one node to the next. The information flows from the input to the output, i.e. from left to right (in some cases, it may be from right to left or both ways).
The nodes of the input layer are passive, meaning they do not modify the data. They receive a single value on their input and duplicate the value to their multiple outputs. Whereas the nodes of the hidden and output layer are active. Thus can they modify the data.
In an interconnected structure, each value from the input layer is duplicated and sent to all of the hidden nodes. The values entering a hidden node are multiplied by weights, a set of predetermined numbers stored in the program. The weighted inputs are then added to produce a single number. Neural networks can have any number of layers and any number of nodes per layer. Most applications use the three-layer structure with a maximum of a few hundred input nodes
Example of Neural Network
Consider a neural network recognizing objects in a sonar signal, and there are 5000 signal samples stored in the PC. The PC has to figure out if these samples represent a submarine, whale, iceberg, sea rocks, or nothing at all? Conventional DSP methods would approach this problem with mathematics and algorithms, such as correlation and frequency spectrum analysis.
While with a neural network, the 5000 samples would be fed to the input layer, resulting in values popping from the output layer. By selecting the proper weights, the output can be configured to report a wide range of information. For instance, there might be outputs for: submarine (yes/no), sea rock (yes/no), whale (yes/no), etc.
With other weights, the outputs can classify the objects as metal or non-metal, biological or non-biological, enemy or ally, etc. No algorithms, no rules, no procedures; only a relationship between the input and output dictated by the values of the weights selected.
Now, let’s understand the concept of Deep Learning.
What is a Deep Learning
Deep learning is a subset of Neural Networks; perhaps you can say a complex Neural Network with many hidden layers.
Technically speaking, Deep learning can also be defined as a powerful set of techniques for learning in neural networks. It refers to artificial neural networks (ANN) that are composed of many layers, massive data sets, and powerful computer hardware to make complicated training models possible. It contains the class of methods and techniques that employ artificial neural networks with multiple layers of increasingly richer functionality.
Structure of Deep learning network
Deep learning networks mostly use neural network architectures and hence are often referred to as deep neural networks. The use of work “deep” refers to the number of hidden layers in the neural network. A conventional neural network contains three hidden layers, while deep networks can have as many as 120- 150.
Deep Learning involves feeding a computer system a lot of data, which it can use to make decisions about other data. This data is fed through neural networks, as is the case in machine learning. Deep learning networks can learn features directly from the data without the need for manual feature extraction.
Examples of Deep Learning
Deep learning is currently being utilized in almost every industry, starting from Automobile, Aerospace, and Automation to Medical. Here are some of examples.
- Google, Netflix, and Amazon: Google uses it in its voice and image recognition algorithms. Netflix and Amazon also use deep learning to decide what you want to watch or buy next
- Driving without a driver: Researchers are utilizing deep learning networks to automatically detect objects such as stop signs and traffic lights. Deep learning is also used to detect pedestrians, which helps decrease accidents.
- Aerospace and Defense: Deep learning is used to identify objects from satellites that locate areas of interest, and identify safe or unsafe zones for troops.
- Thanks to Deep Learning, Facebook automatically finds and tags friends in your photos. Skype can translate spoken communications in real-time and pretty accurately too.
- Medical Research: Medical researchers are using deep learning to automatically detect cancer cells
- Industrial Automation: Deep learning is helping to improve worker safety around heavy machinery by automatically detecting when people or objects are within an unsafe distance of machines.
- Electronics: Deep learning is being used in automated hearing and speech translation.
Read: What is Machine Learning and Deep Learning?
Neural Networks is not new, and researchers have met with moderate success in the last decade or so. But the real game-changer has been the evolution of Deep neural networks.
By outperforming the traditional machine learning approaches it has showcased that deep neural networks can be trained and trialed not just by a few researchers, but it has the scope to be adopted by multinational technology companies to come with better innovations in the near future.
Thanks to Deep Learning and Neural Network, AI is not just doing the tasks, but it has started to think!