activity
20242026
collaborators

14 papers

cs.SE2026

When Surface Form Changes Moderation Decisions: A Paired Study of Code-Mixed Workflow Instability

Suraj Babu Thimma Krishnaram, Yibo Hu, Karthikeyan Saravanan

Hate moderation is often evaluated as classification on clean English inputs, but deployed systems must route content to actions such as ALLOW, FLAG, or REVIEW. We study how this w…

cs.CR2026

DisAgg: Distributed Aggregators for Efficient Secure Aggregation in Federated Learning

Haaris Mehmood, Giorgos Tatsis, Dimitrios Alexopoulos +4

Federated learning enables collaborative model training across distributed clients, yet vanilla FL exposes client updates to the central server. Secure-aggregation schemes protect…

cs.LG2026

DP-LAC: Lightweight Adaptive Clipping for Differentially Private Federated Fine-tuning of Language Models

Haaris Mehmood, Jie Xu, Karthikeyan Saravanan +2

Federated learning (FL) enables the collaborative training of large-scale language models (LLMs) across edge devices while keeping user data on-device. However, FL still exposes se…

cs.LG2026

Differentially Private Clustered Federated Learning with Privacy-Preserving Initialization and Normality-Driven Aggregation

Jie Xu, Haaris Mehmood, Rogier Van Dalen +2

Federated learning (FL) enables training of a global model while keeping raw data on end-devices. Despite this, FL has shown to leak private user information and thus in practice,…

eess.AS2026

FlowW2N: Whispered-to-Normal Speech Conversion via Flow-Matching

Fabian Ritter-Gutierrez, Md Asif Jalal, Pablo Peso Parada +5

Whispered-to-normal (W2N) speech conversion aims to reconstruct missing phonation from whispered input while preserving content and speaker identity. This task is challenging due t…

cs.CL2025

Retrieval Augmented Generation based context discovery for ASR

Dimitrios Siskos, Stavros Papadopoulos, Pablo Peso Parada +3

This work investigates retrieval augmented generation as an efficient strategy for automatic context discovery in context-aware Automatic Speech Recognition (ASR) system, in order…

cs.SD2025

Robust Target Speaker Diarization and Separation via Augmented Speaker Embedding Sampling

Md Asif Jalal, Luca Remaggi, Vasileios Moschopoulos +7

Traditional speech separation and speaker diarization approaches rely on prior knowledge of target speakers or a predetermined number of participants in audio signals. To address t…

eess.AS2025

ValSub: Subsampling Validation Data to Mitigate Forgetting during ASR Personalization

Haaris Mehmood, Karthikeyan Saravanan, Pablo Peso Parada +5

Automatic Speech Recognition (ASR) is widely used within consumer devices such as mobile phones. Recently, personalization or on-device model fine-tuning has shown that adaptation…

eess.AS2025

Diffusion based Text-to-Music Generation with Global and Local Text based Conditioning

Jisi Zhang, Pablo Peso Parada, Md Asif Jalal +1

Diffusion based Text-To-Music (TTM) models generate music corresponding to text descriptions. Typically UNet based diffusion models condition on text embeddings generated from a pr…

eess.AS2025

persoDA: Personalized Data Augmentation for Personalized ASR

Pablo Peso Parada, Spyros Fontalis, Md Asif Jalal +6

Data augmentation (DA) is ubiquitously used in training of Automatic Speech Recognition (ASR) models. DA offers increased data variability, robustness and generalization against di…

eess.AS2024

Exploring compressibility of transformer based text-to-music (TTM) models

Vasileios Moschopoulos, Thanasis Kotsiopoulos, Pablo Peso Parada +7

State-of-the art Text-To-Music (TTM) generative AI models are large and require desktop or server class compute, making them infeasible for deployment on mobile phones. This paper…

cs.LG2024

DP-DyLoRA: Fine-Tuning Transformer-Based Models On-Device under Differentially Private Federated Learning using Dynamic Low-Rank Adaptation

Jie Xu, Karthikeyan Saravanan, Rogier van Dalen +3

Federated learning (FL) allows clients to collaboratively train a global model without sharing their local data with a server. However, clients' contributions to the server can sti…

eess.AS2024

Locality enhanced dynamic biasing and sampling strategies for contextual ASR

Md Asif Jalal, Pablo Peso Parada, George Pavlidis +8

Automatic Speech Recognition (ASR) still face challenges when recognizing time-variant rare-phrases. Contextual biasing (CB) modules bias ASR model towards such contextually-releva…

eess.AS2024

Consistency Based Unsupervised Self-training For ASR Personalisation

Jisi Zhang, Vandana Rajan, Haaris Mehmood +7

On-device Automatic Speech Recognition (ASR) models trained on speech data of a large population might underperform for individuals unseen during training. This is due to a domain…