Publications (44)
Learning Discriminative features using Center Loss and Reconstruction as Regularizer for Speech Emotion Recognition
Suraj Tripathi, Abhiram Ramesh, Abhay Kumar +2
This paper proposes a Convolutional Neural Network (CNN) inspired by Multitask Learning (MTL) and based on speech features trained under the joint supervision of softmax loss and c…
Variance Control via Weight Rescaling in LLM Pre-training
Louis Owen, Abhay Kumar, Nilabhra Roy Chowdhury +1
The outcome of Large Language Model (LLM) pre-training strongly depends on weight initialization and variance control strategies. Although the importance of initial variance contro…
The CUSP CubeSat mission for space weather multi-physics analysis, design, and testing
Giovanni Lombardi, Riccardo Di Spirito, Sergio Fabiani +48
The CUbesat Solar Polarimeter (CUSP) mission aims to measure the linear polarization of solar flares in the hard X-ray band by means of a Compton scattering polarimeter. CUSP is a…
A Hidden Pulse: Uncovering a New Timing Signal in Cygnus X-1 with AstroSat
Sandeep K. Rout, Federico Garcia, Mariano Mendez +4
The study of fast variability properties in X-ray binaries advances our understanding of the physical processes and geometric properties of the accretion flow around the compact ob…
Leveraging User-Generated Reviews for Recommender Systems with Dynamic Headers
Shanu Vashishtha, Abhay Kumar, Lalitesh Morishetti +2
E-commerce platforms have a vast catalog of items to cater to their customers' shopping interests. Most of these platforms assist their customers in the shopping process by offerin…
Focal Loss based Residual Convolutional Neural Network for Speech Emotion Recognition
Suraj Tripathi, Abhay Kumar, Abhiram Ramesh +2
This paper proposes a Residual Convolutional Neural Network (ResNet) based on speech features and trained under Focal Loss to recognize emotion in speech. Speech features such as S…
From Fully Supervised to Zero Shot Settings for Twitter Hashtag Recommendation
Abhay Kumar, Nishant Jain, Suraj Tripathi +1
We propose a comprehensive end-to-end pipeline for Twitter hashtags recommendation system including data collection, supervised training setting and zero shot training setting. In…
Prototype Development and Calibration of the CUbesat Solar Polarimeter (CUSP)
Nicolas De Angelis, Abhay Kumar, Sergio Fabiani +45
The space-based CUbesat Solar Polarimeter (CUSP) mission aims to measure the linear polarization of solar flares in the hard X-ray band by means of a Compton scattering polarimeter…
[Re] Double Sampling Randomized Smoothing
Aryan Gupta, Sarthak Gupta, Abhay Kumar +1
This paper is a contribution to the reproducibility challenge in the field of machine learning, specifically addressing the issue of certifying the robustness of neural networks (N…
Sub-MeV spectroscopy with AstroSat-CZT Imager for Gamma Ray Bursts
Tanmoy Chattopadhyay, Soumya Gupta, Vidushi Sharma +10
Cadmium Zinc Telluride Imager (CZTI) onboard AstroSat has been a prolific Gamma-Ray Burst (GRB) monitor. While the 2-pixel Compton scattered events (100 - 300 keV) are used to extr…
Deep Learning based Emotion Recognition System Using Speech Features and Transcriptions
Suraj Tripathi, Abhay Kumar, Abhiram Ramesh +2
This paper proposes a speech emotion recognition method based on speech features and speech transcriptions (text). Speech features such as Spectrogram and Mel-frequency Cepstral Co…
Exploring Sub-MeV Sensitivity of AstroSat-CZTI for ON-axis Bright Sources
Abhay Kumar, Tanmoy Chattopadhyay, Santosh V Vadawale +5
The Cadmium Zinc Telluride Imager (CZTI) onboard AstroSat is designed for hard X-ray imaging and spectroscopy in the energy range of 20 - 100 keV. The CZT detectors are of 5 mm thi…
The CUbesat Solar Polarimeter (CUSP): mission overview II
Sergio Fabiani, Ettore Del Monte, Andrea Alimenti +46
The CUbesat Solar Polarimeter (CUSP) project is an Earth-orbiting CubeSat mission designed to measure the linear polarization of solar flares in the hard X-ray band using a Compton…
Extending the energy range of AstroSat-CZTI up to 380 keV with Compton Spectroscopy
Abhay Kumar, Tanmoy Chattopadhyay, Santosh V. Vadawale +4
The CZTI (Cadmium Zinc Telluride Imager) onboard AstroSat is a high energy coded mask imager and spectrometer in the energy range of 20 - 100 keV. Above 100 keV, the dominance of C…
Hard X-Ray Focal-Plane Compton Spectro-Polarimeter: Detector Development and Sensitivity Evaluation
Abhay Kumar, Tanmoy Chattopadhyay, Santosh V. Vadawale +1
The scientific potential of X-ray polarimetry has long been recognized, yet the challenges of measuring polarization have left it largely unexplored, mainly in the hard X-ray regim…
Grouped Query Experts: Mixture-of-Experts on GQA Self-Attention
Vishesh Tripathi, Abhay Kumar
Self-attention is central to Transformer performance and is often the most expensive part of the Transformer at long context lengths because its pairwise token interactions scale q…
Biconvex Relaxation for Semidefinite Programming in Computer Vision
Sohil Shah, Abhay Kumar, Carlos Castillo +3
Semidefinite programming is an indispensable tool in computer vision, but general-purpose solvers for semidefinite programs are often too slow and memory intensive for large-scale…
A Study of Dynamic Lorentz Force Detuning of 650 MHz βg= 0.9 Superconducting Radiofrequency Cavity
Abhay Kumar, Arup Ratan Jana, Vinit Kumar
The small bandwidth of superconducting cavities makes the study of dynamic Lorentz force detuning and its compensation indispensable in case of pulsed mode operation of high gradie…
Physics-Informed Neural Network-Based Control for Grid-Forming Converter's Stability Under Overload Conditions
Abhay Kumar, Dushyant Sharma, Mayukha Pal
Grid-forming converters (GFCs) are crucial for frequency and voltage stability in modern power systems. However, their performance under overload conditions remains a challenge. Th…
Streamlining Video Analysis for Efficient Violence Detection
Gourang Pathak, Abhay Kumar, Sannidhya Rawat +1
This paper addresses the challenge of automated violence detection in video frames captured by surveillance cameras, specifically focusing on classifying scenes as "fight" or "non-…
Hard X-ray polarization catalog for a 5-year sample of Gamma-Ray Bursts using AstroSat CZT-Imager
Tanmoy Chattopadhyay, Soumya Gupta, Shabnam Iyyani +16
Cadmium Zinc Telluride Imager (CZTI) aboard AstroSat has been regularly detecting Gamma-Ray Bursts (GRBs) since its launch in 2015. Its sensitivity to polarization measurements at…
ProvocationProbe: Instigating Hate Speech Dataset from Twitter
Abhay Kumar, Vigneshwaran Shankaran, Rajesh Sharma
In the recent years online social media platforms has been flooded with hateful remarks such as racism, sexism, homophobia etc. As a result, there have been many measures taken by…
IndieFake Dataset: A Benchmark Dataset for Audio Deepfake Detection
Abhay Kumar, Kunal Verma, Omkar More
Advancements in audio deepfake technology offers benefits like AI assistants, better accessibility for speech impairments, and enhanced entertainment. However, it also poses signif…
BED: Bi-Encoder-Based Detectors for Out-of-Distribution Detection
Louis Owen, Biddwan Ahmed, Abhay Kumar
This paper introduces a novel method leveraging bi-encoder-based detectors along with a comprehensive study comparing different out-of-distribution (OOD) detection methods in NLP u…
High hard X-ray polarization in Cygnus X-1 confined to the intermediate hard state: evidence for a variable jet component
Tanmoy Chattopadhyay, Abhay Kumar, A. R. Rao +7
Cygnus X-1, the well-known accreting black hole system, exhibits several observational features hinting at an intricate interplay between the accretion disk, its atmosphere known a…
ZClip: Adaptive Spike Mitigation for LLM Pre-Training
Abhay Kumar, Louis Owen, Nilabhra Roy Chowdhury +1
Training large language models (LLMs) presents numerous challenges, including gradient instability and loss spikes. These phenomena can lead to catastrophic divergence, requiring c…
Train Smarter, Not Longer: Memorization-Guided Data Reuse for Efficient LLM Training
Jingwei Zuo, Cong Zeng, Ilyas Chahed +6
The training paradigm of large language models has shifted from traditional one-pass training to multi-epoch training, as reasonable reuse of limited high-quality data can improve…
Solar Flare Hard X-ray Polarimetry with the CUbesat Solar Polarimeter (CUSP) mission
Nicolas De Angelis, Andrea Alimenti, Davide Albanesi +43
The CUbesat Solar Polarimeter (CUSP) project is a CubeSat mission planned for a launch in low-Earth orbit and aimed to measure the linear polarization of solar flares in the hard X…
Electromagnetic Design of β_g= 0.9, 650 MHz Superconducting Radiofrequency Cavity
Arup Ratan Jana, Vinit Kumar, Abhay Kumar +1
We present the electromagnetic design study of a multi cell, β_g= 0.9, 650 MHz elliptic superconducting radiofrequency cavity, which can be used for accelerating H- particles in t…
MTCNET: Multi-task Learning Paradigm for Crowd Count Estimation
Abhay Kumar, Nishant Jain, Suraj Tripathi +2
We propose a Multi-Task Learning (MTL) paradigm based deep neural network architecture, called MTCNet (Multi-Task Crowd Network) for crowd density and count estimation. Crowd count…
Influence of material parameters on the performance of niobium based superconducting RF cavities
Arup Ratan Jana, Abhay Kumar, Vinit Kumar +1
A detailed thermal analysis of a Niobium (Nb) based superconducting radio frequency (SRF) cavity in a liquid helium bath is presented, taking into account the temperature and magne…
Spectral performance of single-channel plastic and GAGG scintillator bars of the CUbesat Solar Polarimeter (CUSP)
Nicolas De Angelis, Abhay Kumar, Sergio Fabiani +45
Our Sun is the closest X-ray astrophysical source to Earth. As such, it makes a formidable case study to better understand astrophysical processes. Solar flares are in particular v…
CUbesat Solar Polarimeter (CUSP) Sensitivity Estimation and Performance Optimization using Geant4
Abhay Kumar, Giovanni Lombardi, Giovanni De Cesare +45
The CUbesat Solar Polarimeter (CUSP) aims to measure the linear polarization of solar flares in the 25-100 keV X-ray band using a Compton scattering polarimeter. CUSP will allow us…
Komodo: A Linguistic Expedition into Indonesia's Regional Languages
Louis Owen, Vishesh Tripathi, Abhay Kumar +1
The recent breakthroughs in Large Language Models (LLMs) have mostly focused on languages with easily available and sufficient resources, such as English. However, there remains a…
In orbit background for hard X-ray CubeSat polarimeters: case study of the CUSP mission in low-earth orbit
Abhay Kumar, Giovanni Lombardi, Riccardo Campana +45
The CUbesat Solar Polarimeter (CUSP) project aims to measure the linear polarization of solar flares in the 25 - 100 keV hard X-ray band using a Compton scattering polarimeter. CUS…
Compton Polarimeter Prototype for the CUbesat Solar Polarimeter (CUSP) mission
Nicolas De Angelis, Andrea Alimenti, Riccardo Campana +41
The paper presents the design, construction, and laboratory testing of a flight‑representative Compton polarimeter prototype for the CubeSat Solar Polarimeter (CUSP) mission, which…
Development of a one-dimensional position sensitive detector for Compton X-ray polarimeters
Abhay Kumar, Santosh V. Vadawale, N. P. S. Mithun +4
The scientific potential of X-ray polarimetry has long been recognized, but the challenges in measuring polarization have left it largely unexplored, particularly in the hard X-ray…
Personalized Product Search Ranking: A Multi-Task Learning Approach with Tabular and Non-Tabular Data
Lalitesh Morishetti, Abhay Kumar, Jonathan Scott +6
In this paper, we present a novel model architecture for optimizing personalized product search ranking using a multi-task learning (MTL) framework. Our approach uniquely integrate…
Exploiting SIFT Descriptor for Rotation Invariant Convolutional Neural Network
Abhay Kumar, Nishant Jain, Chirag Singh +1
This paper presents a novel approach to exploit the distinctive invariant features in convolutional neural network. The proposed CNN model uses Scale Invariant Feature Transform (S…
Visual Context-aware Convolution Filters for Transformation-invariant Neural Network
Suraj Tripathi, Abhay Kumar, Chirag Singh
We propose a novel visual context-aware filter generation module which incorporates contextual information present in images into Convolutional Neural Networks (CNNs). In contrast…
A Refined Analysis of Massive Activations in LLMs
Louis Owen, Nilabhra Roy Chowdhury, Abhay Kumar +1
Motivated in part by their relevance for low-precision training and quantization, massive activations in large language models (LLMs) have recently emerged as a topic of interest.…
On the flow and thermal characteristics of high Reynolds numbers (2800-17000) dye cell: simulation and experiment
G. K. Mishra, Abhay Kumar, O. Prakash +3
This paper presents computational and experimental studies on wavelength/frequency fluctuation characteristics of high pulse repetition rate (PRR: 18 kHz) dye laser pumped by frequ…
Study of the HV power supply modules for the CUbesat Solar Polarimeter (CUSP)
Alessandro Lacerenza, Alda Rubini, Andrea Alimenti +45
The CUbesat Solar Polarimeter (CUSP) project is a CubeSat mission orbiting the Earth aimed to measure the linear polarization of solar flares in the hard X-ray band by means of a C…
The multi-physics analysis, design and testing of CUSP, a CubeSat mission for space weather and solar flares x-ray polarimetry
Giovanni Lombardi, Sergio Fabiani, Ettore Del Monte +45
The space-based CUbesat Solar Polarimeter (CUSP) mission aims to measure the linear polarization of solar flares in the hard X-ray band by means of a Compton scattering polarimeter…