← Charan Sai Ponnada

publications

peer-reviewed work, with abstracts and BibTeX
2025 7th International Symposium on Advanced Electrical and Communication Technologies (ISAECT), Mohali, India · December 2025
Charan Sai Ponnada, Divya Kothapalli, Karthik Goparaju, Sanath Pedapudi
This paper presents a real-time assistive system for outdoor navigation of visually impaired users in complex Indian urban environments. A BLIP vision-language model is fine-tuned through a 3-stage LoRA training strategy on a custom 427-scene dataset built from Google Street View API imagery, yielding a +15.6% improvement across BLEU, METEOR, ROUGE and semantic similarity metrics. The system is deployed on a Raspberry Pi through an edge-cloud hybrid architecture, and covers the full research pipeline: dataset curation, model training, evaluation framework and edge deployment. The trained model is released on HuggingFace and the code is open-sourced.
@inproceedings{ponnada2025vision, title={Vision-Language Based Real-Time Assistive System for Outdoor Navigation of the Visually Impaired in Indian Urban Environments}, author={Ponnada, Charan Sai and Kothapalli, Divya and Goparaju, Karthik and Pedapudi, Sanath}, booktitle={2025 7th International Symposium on Advanced Electrical and Communication Technologies (ISAECT)}, year={2025}, doi={10.1109/ISAECT68904.2025.11318802} }
IEEE International Conference on Computing, Communication and Intelligent Systems (InCODE) 2026 · April 2026 (under review)
Charan Sai Ponnada
This work proposes paraphrase variance across K=5 semantic-preserving rewrites as a label-free, unsupervised proxy for hallucination in large language model outputs, requiring no ground-truth answers at inference time. The signal is evaluated using BERTScore, NLI contradiction rate and AUC-ROC on the TriviaQA and Natural Questions benchmarks. Experiments run on Llama-3-8B-Instruct (BF16, FlashAttention-2) on 2x NVIDIA L40S, and extend to Llama-3-70B for a cross-scale validation claim.
@inproceedings{ponnada2026semantic, title={Semantic Consistency as an Unsupervised Hallucination Signal in Large Language Models}, author={Ponnada, Charan Sai}, booktitle={Proceedings of IEEE InCODE 2026}, year={2026} }
Code and released models are on GitHub and HuggingFace.