Ever heard of Autoencoders?

The first time I saw a Neural Network with more output neurons than in the hidden layers, I couldn't figure how it would work?!

#DeepLearning #MachineLearning
Here's a little something about them: 🧵👇

Autoencoders are unsupervised neural networks whose architecture you can picture as two funnels connect from the narrow ends.

These networks are primary focus for compression tasks of data in Machine Learning.
We feed them the data so that they can learn the most important features, a smaller representation while keep the integrity of the data.

Later when someone needs, can just take that small representation and recreate the original, just like a zip file.📥
Being unsupervised, they require no labels.
Our inputs and outputs are same and a simple euclidean distance can be used as a loss function for measuring the reconstruction.

Of course, we wouldn't expect a perfect reconstruction.
We can think of an autoencoder having two components, encoder and decoder, represented by the below equations:

We are just trying to minimize the L here. All the backpropagation rules still hold.
Advantages over PCA:

▫️ Can learn non-linear transformations, with non-linear activation functions and multiple layers.

▫️ Doesn't have to learn only from dense layers, can learn from convolutional layers too, better for images, videos right?
▫️ More efficient to learn several layers with auto-encoders rather than one huge transformation with PCA

▫️ Can make use of pre-trained layers from another model to apply transfer learning to enhance the encoder /decoder
Some Common Applications:

🔸 Image Colouring
🔸 Feature Variation
🔸 Dimensionality Reduction
🔸 Denoising Image
🔸 Watermark Removal
Some famous types of autoencoders:

🔹 Convolution Autoencoders
🔹 Sparse Autoencoders
🔹 Deep Autoencoders
🔹 Contractive Autoencoders
Here's the first implementation that I did for dimensionality reduction a couple years, minimal code.
🔗https://t.co/AfAdbA6zMi

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Rig Ved 1.36.7

To do a Namaskaar or bow before someone means that you are humble or without pride and ego. This means that we politely bow before you since you are better than me. Pranipaat(प्राणीपात) also means the same that we respect you without any vanity.

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Surrendering False pride is Namaskaar. Even in devotion or bhakti we say the same thing. We want to convey to Ishwar that we have nothing to offer but we leave all our pride and offer you ourselves without any pride in our body. You destroy all our evil karma.

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We bow before you so that you assimilate us and make us that capable. Destruction of our evils and surrender is Namaskaar. Therefore we pray same thing before and after any big rituals.

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तं घे॑मि॒त्था न॑म॒स्विन॒ उप॑ स्व॒राज॑मासते ।
होत्रा॑भिर॒ग्निं मनु॑षः॒ समिं॑धते तिति॒र्वांसो॒ अति॒ स्रिधः॑॥

Translation :

नमस्विनः - To bow.

स्वराजम् - Self illuminating.

तम् - His.

घ ईम् - Yours.

इत्था - This way.

उप - Upaasana.

आसते - To do.

स्त्रिधः - For enemies.

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अति तितिर्वांसः - To defeat fast.

मनुषः - Yajman.

होत्राभिः - In seven numbers.

अग्निम् - Agnidev.

समिन्धते - Illuminated on all sides.

Explanation : Yajmans bow(do Namaskaar) before self illuminating Agnidev by making the offerings of Havi.

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Knowledge & Bharat : Part V

The Curriculum of Vedic Education :
According to the Ancient Indian theory of education, the training of the mind & the process of thinking, are essential for the acquisition of knowledge.

#Thread


Vedic Education System delivered outstanding results.  These were an outcome of the context in which it functioned.  Understanding them is critical in the revival of such a system in modern times. 
The Shanthi Mantra spells out the context of the Vedic Education System.


It says:

ॐ सह नाववतु ।
सह नौ भुनक्तु ।
सह वीर्यं करवावहै ।
तेजस्वि नावधीतमस्तु मा विद्विषावहै ।
ॐ शान्तिः शान्तिः शान्तिः ॥

“Aum. May we both (the guru and disciples) together be protected. May we both be nourished and enriched. May we both bring our hands together and work

with great energy, strength and enthusiasm from the space of powerfulness. May our study and learning together illuminate both with a sharp, absolute light of higher intelligence. So be it.”

The students started the recitation of the Vedic hymns in early hours of morning.


The chanting of Mantras had been evolved into the form of a fine art. Special attention was paid to the correct pronunciation of words, Pada or even letters. The Vedic knowledge was imparted by the Guru or the teacher to the pupil through regulated and prescribed pronunciation,