IIIT Delhi Interview Experience for PhD

Hello everyone! Hope all are healthy and fine.

I applied for a direct Ph.D. at IIIT Delhi. The shortlisting was based on two parameters, Resume and UG marks. Approximately 1400 students applied and 140 were shortlisted.

IIIT Delhi has professors working in various research areas and hence I was shortlisted for two interviews-

1. Related to Computer Graphics, AR, VR.

2. Machine Learning and Deep Learning

Gate Score- 414(2020)

UG Percentage- 88.6(2020)

Interview Date- 18/05/2021

Interview Duration- 47 minutes

Here, I will be sharing my experience of the second interview which was related to Machine Learning, Deep Learning, Computer Vision.

There were 3 members in the panel- Dr. Koteswar Rao, Dr. Vikram Goyal, Dr. Pushpendra Singh.

I- Hello Anubhav, please introduce yourself.

Me- Gave a brief introduction.

I- Tell me about your BTech project.

Me- Told that I had worked on an ergonomic chair for posture correction.

I- What was the motivation behind working on this?

Me- Told about my friend’s father’s back problem due to incorrect sitting postures.

I- Tell the working of the project.

Me- Told the flow of the steps with working.

I- What are you planning to work on(Research interest)?

Me- Computer Vision

Now, I have divided the interview into 3 sections according to the Panel members for better understanding.

P1- Computer Vision/Image Processing

The professor was ready with a series of 6 questions which he showed one by one on his screen. The questions were Case Study type and he was pushing to think how to solve them by giving hints also if needed.

Questions asked were:

1. He showed a Gray Scale image of a square shape with the leftmost side as Black and the rightmost side as white. The black color was fading from left to right. How can you draw a similar image using an array in C language?
2. An image of a boy was shown moving towards the right. The question was asked that what would happen if we transpose the image. In which direction will the boy seem moving now?
3. An image of a building was shown. Inside the image, there were some isolated points/pixels. The question asked was how will you detect the isolated pixels in the image.
4. An animation of a man doing dumbells was shown, also the coordinates of the wrist, elbow, and shoulder were given. We needed to count the number of times he lifted the dumbbell?
5. A black image was shown with some white-colored objects drawn inside it. It was looking like a 3X3 matrix. The question asked was how to count the number of white objects inside the image?
6. A question related to the trigonometric ratios was asked involving two ladders leaning on two walls on opposite sides.

These questions were asked by Koteswar sir, he was very helpful and appreciative during the interview, frequently providing some hints to reach the answer.

P2- The second panelist was Dr. Pushpendra, he asked about the subjects of my interest which I studied in my BTech.

I told them I liked Data Structures, Operating Systems, and DBMS. Questions asked were

1. What is scheduling in Operating Systems?
2. Types of Scheduling?
3. He told a Case Study and then asked which scheduling algorithm will be best suited for the purpose stated. It involved iterative processes so, I said that Round Robin will be best suited.
4. The above was followed with lots of cross-questioning.
5. Consider a single-core processor with no threading possible. Suppose the Round-Robin scheduler allocates the processor to process P1 with a specific time quantum. Now, the time quantum allocated to P1 is finished, but the scheduler is now present in the memory. How will it preempt the process P1 and give entry to P2?

The answer was through Interrupt.

P3- Now, the third professor started questioning me on Data Structures.

Questions asked were:

1. He gave a Case Study basically to know the difference between Linked List and Array from me.
2. How to detect a loop in a Linked List?
3. He gave another Case Study related to the minimum binary heap.
4. What are the properties of a minimum heap?
5. How will you prove the basic property of a binary min-heap that the second smallest element lies in the second level of the heap?

With this, my interview came to an end. I was satisfied with my performance and they told me that they will contact me if I was selected.

The professors were very helpful and calm. It was one of the best interviews I have ever given.

I hope it will help some of you with your interviews. Good luck!