In today’s world, images are ubiquitous, from the photographs we take, the videos we watch on youtube, and the images such as XRays, CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) scans acquired in a hospital to satellite images. These images form an important tool for visualisation or representation of data. Our group has been working on a variety of algorithms for processing such image data to improve their appearance and to make them more useful, which also includes acquiring them faster A few highlights of the work we have been engaged in are
presented here below:

While digital imaging has taken the world by storm, there are many trying situations when it is quite difficult to take pictures from a smartphone or a handheld camera. One of the scenarios where we may consider using a drone for imaging is to capture a panorama of an extensive building, or when an inspector wants to examine defects in, say, the iconic Worli Sea Bridge.

Computer systems affect diverse aspects of our lives today. From the mobile phones we use to the cars, trains and airplanes we ride and fly in, from the ATMs dispensing money to the EVMs used in elections, from the life-support systems in ICUs to railway signaling systems, (embedded) computer systems silently pervade our lives. Needless to say, software or hardware bugs in these systems can have wide ranging consequences, from mere inconvenience to even loss of lives.

Cloud computing is the concept of computing as a utility bringing the illusion of infinite computing power with a pay-as-you-use model of billing to the consumer. It is analogous to the concept of other utilities such as water and electricity, but applied to computing. Cloud computing services are segregated into three layers based on the abstractions they provide:

Our group specialises in the field of geophysical signal analysis. We have been working on implementation of novel signal analysis techniques such as wavelet transform, multifractal and empirical mode decomposition analyses to a variety of geophysical signals of diverse origins. These techniques help unravel the hidden information from the signals that cannot in general be possible to obtain with conventional signal analysis tools. The group maintains a library of all the software indigenously developed in Matlab, C, C++ and C# languages for the above techniques.

Shock waves are phenomena occurring in compressible fluids such as gases in which very large difference in pressure can occur over a very small distance. A shock wave can be thought of as a very thin front across which a large pressure increase exists, with the front moving rapidly in the fluid medium in which it is created. The sound waves generated when we speak are essentially very weak shock waves. When explosives go off, the shock wave generated as a consequence of the explosion is responsible for the damage that happens to the surroundings.

Vehicles that re-enter earth’s atmosphere from space come in at very high speeds that are classified as hypersonic speeds. The speed may well exceed more than ten times the local speed of sound. Such high speed flows generate a shock in front of the re-entry vehicle which affects the heat flux on its surface. The heat flux on the surface of the re-entry vehicle is an extremely important design parameter, and an accurate prediction of this parameter is a critical task.

For more than 2 millennia, science has progressed primarily by experimental observations and development of theories. These two methods work perfectly in conjunction with one another in developing our understanding of the physical world around us. In the past few decades, a third significant methodology employing powerful computers and computational science for simulations has greatly added to our scientific capability and understanding.

The smoothed particle hydrodynamics (SPH) method is a general-purpose numerical method that can be used to simulate a wide variety of problems. These problems range from astrophysics, incompressible and compressible fluid dynamics, to structural dynamics problems. SPH is a particle-based method and works by representing continuous fields using a collection of moving particles. The method does not depend on a fixed mesh and therefore works well for complex geometries, free-surface, and multi-physics problems.

India supports around 17.5% of the world’s population on a mere 2.4% of the Earth’s surface prone to global and regional climate change effects. Scientific research has largely focused on using models as inseparable components of climate studies. For a genuine understanding and realistic representation by which land surface processes influences climate, the role of land surface models (LSM) can never be overstated.

The road accident report (2014) published by the road transport and highways ministry, reports 6,672 deaths in accidents caused due to bad roads. Currently, road authorities manually monitor long stretches of roads at regular time intervals to ascertain the presence and locations of road anomalies. This is evidently a tedious process, which often leads to delayed road repairs, whose severity increases with time.

SAFE (Smart Authenticated Fast Exams) is a smart-phone app based system to conduct easy online-exams in proctored venues. Today, smart-phones or other electronic devices are explicitly disallowed in exam venues, due to the obvious possibilities of misuse for cheating. SAFE brings the smart-phone revolution into the exam hall.

Online repositories contain millions of 3D shapes, providing data for a wide range of data-driven 3D modeling interfaces. Such interfaces facilitate, accelerate and democratise computer-aided design and 3D content creation. By automatically learning design rules and structural principles from training data, these interfaces allow even novice and casual users to design complex and functional objects.

Many real world phenomena, like fluid flows, combustion, and garment drapes demonstrate astonishing complexity of structure, movement and appearance. Efficient and accurate simulation and animation of these play a crucial part in many applications ranging from scientific visualisation to advertising, from computer aided design to retail and from entertainment to medicine.

Our group’s research is motivated by the goal of creating intelligent agents, especially ones that can learn. In pursuit of this goal, we consider questions from a wide variety of topics. Central to our investigation is reinforcement learning (RL), which is a general paradigm for an agent, through trial and error, to discover actions that maximise its long-term gain. RL finds application in a variety of domains, including game-playing, stock-trading, medical decision-making, and environmental preservation.

Earth observation image data are mainly characterised by (i) Spatial resolution – the ability of the imaging sensor to focus on very small areas and thereby distinguish between closely spaced features, and (ii) Spectral resolution – ability to observe the targets in a number of narrow wavelength bands of the electromagnetic spectrum.

High spatial resolution images allow image analysis based on objects (regions) in terms of their shape, size, and spectral homogeneity, examples which can be seen below:

िहंदीशब्दमित्र(Hindi Shabdamitra) is an e-learning product meant for Hindi language teaching and learning.It uses Hindi Wordnet which is further augmented with audio-visual features, grammatical properties and is presented in a learner-friendly layered format.

Integrated computational materials engineering (ICME) has two key components namely multi-scale modeling beginning with first principles and data informatics for better design of products. Both components are focused on shortercycle of product development and efficient use of materials and resources leading to lower cost of manufacturing.‘Integrated’ means integration of interdisciplinary technology to desired product via multi-scale  qmodeling. In the ‘bottom-up’ approach of ICME one starts from first principles, designs a material for a given application.

Reactivity initiated accident (RIA) or loss of coolant accident (LOCA) in a nuclear reactor may lead to sudden temperature rise. Accidents caused by RIA or LOCA condition may lead to a dynamic expansion of fuel pallets. This results into a multi-axial state of deformation caused by high thermal loading (1000 o Cs -1 ) in presence of extreme conditions of irradiation. Low temperature in early stage transient, metal-water reaction and accumulated irradiation in a high burn-up clad may also lead to a brittle failure.

Bulk metallic glasses (BMGs) are amorphous alloys with enhanced properties such as high strength, large elastic strain, corrosion resistance, high fatigue and fracture toughness in comparison with their crystalline counterparts. This makes BMGs suitable for deployment in many applications. However, upon loading uniaxially beyond their yield point, most BMGs fail catastrophically, displaying very little plastic strain. This limits the use of BMGs in load bearing applications.