Device Modelling
High power VLSI Design
HEMT
Nano electronics
31
Scopus Publications
185
Scholar Citations
7
Scholar h-index
4
Scholar i10-index
Scopus Publications
Deep Unfolding-Based Graph Transformer Framework for Early Detection of Diabetic Retinopathy Using OCT Images Aaron Bose, Nirmal Varghese Babu, J. S Rajkumar Proceedings of the 4th International Conference on Intelligent Data Communication Technologies and Internet of Things Idciot 2026, 2026 Diabetic Retinopathy (DR) is a serious diabetes complication and a major cause of avoidable blindness, and hence its early and proper detection is important. The current research offers a smart risk prediction framework for DR from Optical Coherence Tomography (OCT) images, diagnosing the disease in four grades: Normal, Mild, Moderate, and Severe. In order to improve the image quality, a Deep Unfolding Network (DUN) removes speckle noise with maintaining retinal structures. To balance datasets, a Latent Diffusion Model (LDM) produces high-quality synthesized OCT images at all steps. Features are extracted by a Swin Transformer with Retinal Layer Attention (RLA-Swin), retaining both global patterns and subtle anatomical details. A Concrete Autoencoder (CAe) extracts important features, and a Graph Convolutional Network (GCN) classifies them final. Results show 98.5% accuracy with excellent precision, recall, and F1-scores. The model is able to efficiently deal with noise, data scarcity, and small stage differences, presenting a solid, interpretable, and clinically useful instrument for detecting DR early.
Multi-Domain EEG Fusion and Hybrid Ensembles for ADHD Subtype Intelligence Angela Ann Mathew, Nirmal Varghese Babu, J. S Rajkumar Proceedings of the 4th IEEE International Conference on Interdisciplinary Approaches in Technology and Management for Social Innovation Iatmsi 2026, 2026 Identifying Attention Deficit Hyperactivity Disorder (ADHD) accurately by electroencephalography (EEG) signals remains a challenging task mostly because of the variability among subjects and the limited amount of data. The present study presents a novel framework for EEG-based ADHD analysis encompassing preprocessing, physiologically con- strained data augmentation, comprehensive feature extraction, feature selection, and hybrid ensemble classification steps towards precise subtype differentiation. EEG data from the Healthy Brain Network is preprocessed through the PERSONA pipeline, which consists of bandpass and notch filtering, adaptive artifact rejection, spectral-spatial reconstruction, wire referencing, and Z-normalization that together maintain the essential spectralcharacteristics. PHYS-AUG generates physiologically plausibleaugmentations in the temporal, spectral, and spatial areas usingsubject-aware mixup to keep the critical spectral ratios and soit takes care of data scarcity. Feature extraction with WIDE- BANK covers various domains such as temporal, spectral, decom- position, time-frequency, nonlinear, connectivity, cross-frequencycoupling, and microstate/topographic, capturing the aspects ofamplitude, complexity, oscillatory modes, synchronization, andhierarchical neural interactions respectively. TRI-SELECT cutsdown the high-dimensional feature set (20-40 features) byapplying low-variance filtering, correlation pruning, statisticalranking, mRMR, XGBoost importance, and genetic algorithmoptimization. STACK-MIND, a two-level ensemble combiningvarious base learners with a logistic regression meta-learner,achieve an accuracy of 96.0%, thus proving to be very robust,stable, and generalizable in detecting ADHD.
Adaptive Temporal-Spatial Attention Framework for Early Epileptic Seizure Prediction Using Multichannel EEG Signals Jeffrey Chris, Nirmal Varghese Babu, J. S Rajkumar 2026 6th International Conference on Advances in Electrical Computing Communications and Sustainable Technologies Icaect 2026, 2026 Epileptic seizure prediction from electroencephalogram (EEG) signals plays a critical role in improving the safety and quality of life of individuals living with epilepsy. This study proposes a robust multi-stage seizure prediction framework that integrates noise reduction, data enrichment, spectral decomposition, dynamic connectivity learning, optimal feature selection, and attention-driven classification. Initially, Adaptive Neuro-Clean Filtering (ANCF) removes noise components while preserving seizure-relevant neural dynamics. To mitigate class imbalance and enhance model generalization, a Temporal-Physiological Mixup (TPMix) strategy generates physiologically consistent synthetic EEG samples. The refined signals are further processed using the Multivariate Adaptive Synchro-Spectral Transform (MASST) to extract high-quality time-frequency representations. Dynamic Graph Spectral Connectivity (DGSC) features are derived to capture evolving inter-channel relationships, and Hybrid Quantum-Optimized Fisher Selection (HQFS) chooses compact yet discriminative feature subsets. Finally, a TemporalSpatial Attention Graph Neural Network (TSAGNN) jointly models long-range temporal dependencies and spatial brainregion interactions to classify EEG into pre-ictal, ictal, post-ictal, and normal states. Experimental evaluation on the CHB-MIT dataset achieved an overall accuracy of 95.9%, demonstrating the model's strong predictive capability and clinical relevance.
Few-Shot Urgency Classification of Crisis Tweets via Multi-View Feature Learning Renimol S, Nirmal Varghese Babu P, J. S Rajkumar Proceedings of the 4th IEEE International Conference on Interdisciplinary Approaches in Technology and Management for Social Innovation Iatmsi 2026, 2026 The detection of crises through social media that is effective and timely is imperative for disaster response and humanitarian aid. The crisis tweet classification scheme proposed in this paper is a new urgency-aware crisis tweet classifier that combines multi-domain feature representations with few-shot learning to overcome the challenges of data scarcity and noisy user content. The authors collected the crisis tweets from Twitter and enriched them with CrisisLex, and CrisisNLP datasets annotated by their respective urgency levels (Critical, High, Moderate, Low) and types of help required which included temporal and geospatial metadata. Preprocessing takes advantage of Urgency-Preserving Contextual Encoding (UPCE) that successfully captures emojis, punctuation, capitalization, and temporal cues which express distress. Crisis-Adaptive MixUp (CAMU) creates new tweets to boost generalization of the underrepresented classes. Multi-Domain Urgency Feature Extraction Framework (MD-UFEF) is used in feature extraction whereby lexical, syntactic, semantic, and contextual signals are first encoded then followed by Urgency-Adaptive Feature Selection (UAFS) which retains the most salient features per class. Classification employs Urgency-Specific Few-Shot Learning (US-FSL), a combination of metric learning and attention-based weighting enabling accurate tweet categorization even with scant labeled data. The experimental results show that the UPCE+CAMU+US-FSL scheme developed is better than the baselines, with a 93.5% accuracy and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$91.6 \% \mathrm{F} 1$</tex>-score for urgency classification and a 91.0% accuracy for help-type classification. The few-shot experiments demonstrate that high performance can be achieved with only 20 support samples per class. The framework is so efficient in computation and at the same time reliable in prediction that it is well suited for real-time crisis detection and management.
PREDICTIVE MODELS FOR EARLY DETECTION OF PARKINSON’S DISEASE: A MACHINE LEARNING APPROACH S. Jeyantha Jafna Juliet, D. Jasmine David, J. S. Raj Kumar, Angelin Jeba P., R. Golden Nancy, M. Selvarathi, T. Jemima Jebaseeli Journal of Mechanics of Continua and Mathematical Sciences, 2025 Motor symptoms, such as tremors, bradykinesia, stiffness, and posture issues, are produced by the loss of dopamine-producing neurons in the spinal column portion of the brain, which is characteristic of Parkinson's disease (PD). To properly control and treat PD, the condition must be identified as soon as possible. Machine learning techniques, which use data-driven methodologies, provide intriguing possibilities for reaching this aim. These methods involve the analysis of various types of data, including clinical assessments, imaging scans, and genetic markers, to develop accurate predictive models. Even in the initial stages of the conditions, machine learning techniques can discriminate between patients who have and do not have PD by identifying minor variations and traits from such multivariate data. These models support early diagnosis and enable personalized treatment strategies tailored to the specific needs of patients. Additionally, integrating wearable sensors and mobile health technologies further enhances the feasibility of continuous monitoring and early detection, providing patients and healthcare practitioners with the tools they need to manage PD proactively. To identify diseases, one can access vast databases of medical information. To diagnose PD, the proposed method uses two different data sets. Algorithms for machine learning are also capable of helping in producing specific details from such data. The proposed research applies a few Machine Learning ways to anticipate Parkinson's disease by human guidance, with the dataset acting as the source of the process understanding. By applying the hyperparameter optimization process, the accuracy is estimated. When used to diagnose Parkinson's disease (PD), the proposed methods produce accuracy rates of 98.9% for Naive Bayes and 97.3% for Logistic Regression.
BERT-Based Agricultural Crop Prediction System Using Soil and Weather Parameters with Interactive Streamlit Deployment Naren L, Raj Kumar. J. S 4th International Conference on Applied Artificial Intelligence and Computing Icaaic 2025, 2025 Accurate crop selection plays a crucial role in improving agricultural productivity and resource utilization, especially under varying soil and climatic conditions. Traditional crop recommendation systems often rely on statistical or shallow learning models that fail to capture contextual relationships among agronomic parameters. This work proposes a BERT-Based Agricultural Crop Prediction System that converts numerical soil and weather parameters—Nitrogen, Phosphorus, Potassium (NPK), soil pH, temperature, humidity, rainfall, and soil type—into structured natural-language descriptors to leverage contextual embeddings from Bidirectional Encoder Representations from Transformers (BERT). The extracted embeddings are then passed to a custom classification head to recommend the most suitable crop among 22 crop types. The system is deployed using Streamlit, enabling interactive input, ranked top-3 recommendations, and explainability through SHAP visualizations. Experimental evaluation demonstrates that the proposed model achieves 92% accuracy, significantly outperforming baseline models including Random Forest, SVM, and LSTM. These results confirm the effectiveness of contextual language models for precision agriculture and decision support in field environments.
Enhanced Multi-Class Cardiac Sound Diagnosis using Advanced PCG Signal Analysis and Deep Learning Integration 16th International Conference on Advances in Computing Control and Telecommunication Technologies Act 2025, 2025
MediScan: An AI-Powered Multi-Disease Diagnostic Support System Using Medical Imaging Abel Mathew Thomas, Rajkumar J S, Nirmal Varghese Babu 4th International Conference on Applied Artificial Intelligence and Computing Icaaic 2025, 2025 The rapid advancement of artificial intelligence (AI) in healthcare offers substantial potential for augmenting clinical decision-making and reducing diagnostic errors. Medical imaging, in particular, generates vast volumes of data that require expert interpretation, often leading to diagnostic delays due to a shortage of qualified radiologists and pathologists. To address these issues, this paper introduces MediScan, an AI-driven diagnostic framework that leverages deep learning models like Convolutional Neural Networks (CNNs) and U-Net to assist in multi-disease classification and segmentation of medical images. Evaluated on standard datasets including ChestX-ray14, ISIC 2018, and BraTS, the system demonstrates strong performance, achieving a 92.3 percent classification accuracy for thoracic conditions and a 0.87 Dice Similarity Coefficient for brain tumor segmentation. A key feature of the framework is the integration of explainable AI through Gradient-weighted Class Activation Mapping (Grad-CAM), which generates visual heatmaps to improve model transparency and foster clinician trust. By delivering fast, precise, and interpretable results, MediScan demonstrates the potential for a scalable and accessible diagnostic tool that can alleviate pressure on healthcare systems, promote early disease intervention, and improve patient outcomes.
Explainable Digital Twin Framework for Aircraft Engine Maintenance Chris Joseph George, J.S Rajkumar, Nirmal Varghese Babu International Conference on Nexgen Networks and Cybernetics Ic2nc 2025 Proceedings, 2025 Growing dependence of modern aviation on aircraft engines underscores persistent challenges in balancing safety, reliability, and operational costs. Conventional maintenance practices, whether preventive or reactive, often prove inadequate, leading to premature component replacement, unscheduled downtime, and limited diagnostic transparency. To address these gaps, this study proposes an AI-driven digital twin framework that integrates predictive modeling, explainability, immersive visualization, and secure data management for aircraft engine maintenance. A Python-based simulator generates realistic IoT sensor streams replicating operational stresses, gradual degradation, and subtle anomalies, which are then analyzed using complementary machine learning models: an Isolation Forest for anomaly detection and a Random Forest Regressor for Remaining Useful Life (RUL) estimation. SHAP-based interpretability ensures that predictions remain transparent and traceable, a critical requirement for aviation applications. The framework further incorporates Unity 3D for interactive engine visualization and a Flutter mobile application for field-level accessibility, while blockchain-backed IoT logging and federated learning strengthen data integrity and collaborative scalability. Validation on synthetic datasets and the NASA C-MAPSS benchmark confirms improved robustness, with the Random Forest reducing RUL prediction error by over $30 \%$ and the Isolation Forest achieving an F1-score of 0.89 for anomaly detection. These results specify the framework’s potential as a transparent, scalable, and industry-ready solution for predictive maintenance in aviation, with adaptability to other safety-critical domains such as manufacturing and energy.
Few-Shot Urgency Classification of Crisis Tweets via Multi-View Feature Learning S Renimol, JS Rajkumar 2026 IEEE International Conference on Interdisciplinary Approaches in … , 2026 2026
Multi-Domain EEG Fusion and Hybrid Ensembles for ADHD Subtype Intelligence AA Mathew, NV Babu, JS Rajkumar 2026 IEEE International Conference on Interdisciplinary Approaches in … , 2026 2026
Deep Unfolding-Based Graph Transformer Framework for Early Detection of Diabetic Retinopathy Using OCT Images A Bose, NV Babu, JS Rajkumar 2026 4th International Conference on Intelligent Data Communication … , 2026 2026
Adaptive Temporal–Spatial Attention Framework for Early Epileptic Seizure Prediction Using Multichannel EEG Signals J Chris, NV Babu, JS Rajkumar 2026 Sixth International Conference on Advances in Electrical, Computing … , 2026 2026
MediScan: An AI-Powered Multi-Disease Diagnostic Support System Using Medical Imaging AM Thomas, JS Rajkumar, NV Babu 2025 4th International Conference on Applied Artificial Intelligence and … , 2025 2025
HematoScribe AI: A Transparent & Explainable System for Bone Marrow Cell Analysis S Sam, RK JS, NV Babu, RG Nancy 2025 6th International Conference on IoT Based Control Networks and … , 2025 2025
Multi-Modal AI Personal Health Risk Prediction and Early Alert System AB Abraham, RK JS, NV Babu, RG Nancy 2025 4th International Conference on Automation, Computing and Renewable … , 2025 2025
Explainable Digital Twin Framework for Aircraft Engine Maintenance CJ George, JS Rajkumar, NV Babu 2025 International Conference on NexGen Networks and Cybernetics (IC2NC … , 2025 2025
Semantic Kernel for Software Engineering: A Multi-Agent Framework for Autonomous Development Lifecycles BV Adithya, RK JS, NV Babu 2025 9th International Conference on Electronics, Communication and … , 2025 2025
Nanosheet transistors: materials, devices, systems and applications A Angelin Delighta, JS Raj Kumar, IV Binola K Jebalin, D Nirmal Journal of Materials Science 60 (16), 6769-6806 , 2025 2025 Citations: 3
Forest wildfire detection from satellite image using deep learning D Elizaroshan, JSR Kumar 2024 International Conference on Communication, Computing and Internet of … , 2024 2024 Citations: 2
Monitoring industrial protection gear using intelligent system M Yakubraj, JS Rajkumar, S Sophas Samuel, G Matthew Palmer, ... 2024 2nd International Conference on Networking and Communications (ICNWC), 1-6 , 2024 2024 Citations: 5
Investigations of ScAlN/AlGaN split barrier inspired high electron mobility transistor JSR Kumar, D Nirmal, HVD John, KB Jebalin AIP Conference Proceedings 2901 (1), 080018 , 2023 2023 Citations: 2
A comprehensive review of AlGaN/GaN High electron mobility transistors: Architectures and field plate techniques for high power/high frequency applications JSR Kumar, HV Du John, BKJ IV, J Ajayan, D Nirmal Microelectronics Journal 140, 105951 , 2023 2023 Citations: 43
Anesthetic Management in a 4-Year-Old Child Undergoing Removal of a Gemstone Tracheobronchial Foreign Body R Kumar, TK Jayakumar, A Sinha, S Kumar Journal of Indian Association of Pediatric Surgeons 28 (5), 448-449 , 2023 2023
Simulation Study of Stacked Oxide Layer NCFET for RF Applications VS Navya, HV Du John, JSR Kumar, A Franklin, D Nirmal 2023 8th International Conference on Communication and Electronics Systems … , 2023 2023
Investigation on Fe-Doped AlGaN/GaN HEMT at 148 GHz Using E-FPL Technology for High-Frequency Communication Systems SA Franklin, S Chander, JSR Kumar, J Ajayan, D Nirmal ECS Journal of Solid State Science and Technology 12 (3), 035006 , 2023 2023 Citations: 4
Investigation on L G = 50 nm Tapered T-Gated AlGaN/GaN HEMT on Silicon Wafer with a f T /f max of 264/312 GHz for beyond 5G (B5G) Applications JSR Kumar, D Nirmal, J Ajayan, S Tayal Silicon 14 (17), 11315-11322 , 2022 2022 Citations: 10
Design and simulation of a T-gated AlGaN/GaN HEMT with added mini field plate JSR Kumar, D Nirmal, HV Du John, SA Franklin, G Samuel 2022 3rd International Conference on Electronics and Sustainable … , 2022 2022 Citations: 3
Intensive study of field-plated AlGaN/GaN HEMT on silicon substrate for high power RF applications JSR Kumar, D Nirmal, MK Hooda, S Singh, J Ajayan, L Arivazhagan Silicon 14 (8), 4277-4282 , 2022 2022 Citations: 23
MOST CITED SCHOLAR PUBLICATIONS
Improved RF and DC performance in AlGaN/GaN HEMT by P-type doping in GaN buffer for millimetre-wave applications L Arivazhagan, D Nirmal, D Godfrey, J Ajayan, P Prajoon, ASA Fletcher, ... AEU-International Journal of Electronics and Communications 108, 189-194 , 2019 2019 Citations: 55
A comprehensive review of AlGaN/GaN High electron mobility transistors: Architectures and field plate techniques for high power/high frequency applications JSR Kumar, HV Du John, BKJ IV, J Ajayan, D Nirmal Microelectronics Journal 140, 105951 , 2023 2023 Citations: 43
Intensive study of field-plated AlGaN/GaN HEMT on silicon substrate for high power RF applications JSR Kumar, D Nirmal, MK Hooda, S Singh, J Ajayan, L Arivazhagan Silicon 14 (8), 4277-4282 , 2022 2022 Citations: 23
Investigation on L G = 50 nm Tapered T-Gated AlGaN/GaN HEMT on Silicon Wafer with a f T /f max of 264/312 GHz for beyond 5G (B5G) Applications JSR Kumar, D Nirmal, J Ajayan, S Tayal Silicon 14 (17), 11315-11322 , 2022 2022 Citations: 10
AlGaN/GaN HEMT for highly sensitive detection of Bio-molecules using transconductance method PP Kumar Reddy, SB Lakshmi, L Arivazhgan, JS Raj Kumar, D Nirmal IOP conference series: materials science and engineering 872 (1), 012048 , 2020 2020 Citations: 8
Modeling of self-heating for AlGaN/GaN HEMT with thermal conductivity degradation effect L Arivazhagan, D Nirmal, J Ajayan, D Godfrey, JS Rakkumar, SB Lakshmi AIP Conference Proceedings 2201 (1), 020010 , 2019 2019 Citations: 7
DC Performance analysis of AlGaN/GaN HEMT for future High power applications PP Pandit, L Arivazhagan, P Prajoon, JS Rajkumar, J Ajayan, D Nirmal 2018 4th International Conference on Devices, Circuits and Systems (ICDCS … , 2018 2018 Citations: 7
Monitoring industrial protection gear using intelligent system M Yakubraj, JS Rajkumar, S Sophas Samuel, G Matthew Palmer, ... 2024 2nd International Conference on Networking and Communications (ICNWC), 1-6 , 2024 2024 Citations: 5
Variable thermal resistance model of GaN-on-SiC with substrate scalability L Arivazhagan, D Nirmal, S Chander, J Ajayan, D Godfrey, JS Rajkumar, ... Journal of Computational Electronics 19 (4), 1546-1554 , 2020 2020 Citations: 5
Investigation on Fe-Doped AlGaN/GaN HEMT at 148 GHz Using E-FPL Technology for High-Frequency Communication Systems SA Franklin, S Chander, JSR Kumar, J Ajayan, D Nirmal ECS Journal of Solid State Science and Technology 12 (3), 035006 , 2023 2023 Citations: 4
Self-heating analysis of GaN-HEMT for various ambient temperature and substrate thickness L Arivazhagan, AHM Jarndal, S Chander, D Godfrey, RK JS, ... 2020 5th International Conference on Devices, Circuits and Systems (ICDCS … , 2020 2020 Citations: 4
Nanosheet transistors: materials, devices, systems and applications A Angelin Delighta, JS Raj Kumar, IV Binola K Jebalin, D Nirmal Journal of Materials Science 60 (16), 6769-6806 , 2025 2025 Citations: 3
Design and simulation of a T-gated AlGaN/GaN HEMT with added mini field plate JSR Kumar, D Nirmal, HV Du John, SA Franklin, G Samuel 2022 3rd International Conference on Electronics and Sustainable … , 2022 2022 Citations: 3
Forest wildfire detection from satellite image using deep learning D Elizaroshan, JSR Kumar 2024 International Conference on Communication, Computing and Internet of … , 2024 2024 Citations: 2
Investigations of ScAlN/AlGaN split barrier inspired high electron mobility transistor JSR Kumar, D Nirmal, HVD John, KB Jebalin AIP Conference Proceedings 2901 (1), 080018 , 2023 2023 Citations: 2
Enhancement of drain current in AlGaN/GaN HEMT using AlN passivation L Arivazhagan, D Nirmal, J Ajayan, D Godfrey, JS Rajkumar, SB Lakshmi AIP Conference Proceedings 2201 (1), 020009 , 2019 2019 Citations: 2
DC and RF Analysis of AlGaN/GaN MOS-HEMT for High Power Application JSR Kumar, D Nirmal, L Arivazhagan, PP Pandit 2019 2nd International Conference on Signal Processing and Communication … , 2019 2019 Citations: 2
Few-Shot Urgency Classification of Crisis Tweets via Multi-View Feature Learning S Renimol, JS Rajkumar 2026 IEEE International Conference on Interdisciplinary Approaches in … , 2026 2026
Multi-Domain EEG Fusion and Hybrid Ensembles for ADHD Subtype Intelligence AA Mathew, NV Babu, JS Rajkumar 2026 IEEE International Conference on Interdisciplinary Approaches in … , 2026 2026
Deep Unfolding-Based Graph Transformer Framework for Early Detection of Diabetic Retinopathy Using OCT Images A Bose, NV Babu, JS Rajkumar 2026 4th International Conference on Intelligent Data Communication … , 2026 2026