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Athanasios Mouchtaris

27 accepted papers

2025

Context-aware Dynamic Pruning for Speech Foundation Models

ICLR 2025poster

Foundation models, such as large language models, have achieved remarkable success in natural language processing and are evolving into models capable of handling multiple modalities. Listening ability, in particular, is crucial for many applications, leading to research on building speech foundatio…

Cited by 0SourcePDFScholar
2025

MaZO: Masked Zeroth-Order Optimization for Multi-Task Fine-Tuning of Large Language Models

EMNLP 2025

Large language models have demonstrated exceptional capabilities across diverse tasks, but their fine-tuning demands significant memory, posing challenges for resource-constrained environments. Zeroth-order (ZO) optimization provides a memory-efficient alternative by eliminating the need for backpro

Cited by 0SourcePDFScholar
2025

QuZO: Quantized Zeroth-Order Fine-Tuning for Large Language Models

EMNLP 2025

Large Language Models (LLMs) are often quantized to lower precision to reduce the memory cost and latency in inference. However, quantization often degrades model performance, thus fine-tuning is required for various downstream tasks. Traditional fine-tuning methods such as stochastic gradient desce

Cited by 0SourcePDFScholar
2025

Saten: Sparse Augmented Tensor Networks for Post-Training Compression of Large Language Models

EMNLP 2025

The efficient implementation of large language models (LLMs) is crucial for deployment on resource-constrained devices. Low-rank tensor compression techniques, such as tensor-train (TT) networks, have been widely studied for over-parameterized neural networks. However, their applications to compress

2025

Wanda++: Pruning Large Language Models via Regional Gradients

ACL 2025finding

Large Language Models (LLMs) pruning seeks to remove unimportant weights for inference speedup with minimal accuracy impact. However, existing methods often suffer from accuracy degradation without full-model sparsity-aware fine-tuning. This paper presents Wanda++, a novel pruning framework that out…

Cited by 0SourcePDFScholar
2024

AdaZeta: Adaptive Zeroth-Order Tensor-Train Adaption for Memory-Efficient Large Language Models Fine-Tuning

EMNLP 2024main

Fine-tuning large language models (LLMs) has achieved remarkable performance across various natural language processing tasks, yet it demands more and more memory as model sizes keep growing. To address this issue, the recently proposed Memory-efficient Zeroth-order (MeZO) methods attempt to fine-tu…

2024

Max-Margin Transducer Loss: Improving Sequence-Discriminative Training Using a Large-Margin Learning Strategy

ICASSP 2024accepted

In this work, we propose a novel sequence-discriminative training criterion for automatic speech recognition (ASR) based on the Conformer Transducer. Inspired by the large-margin classifier framework, we separate the "good" and the "bad" hypotheses in an N-best list produced from a pre-trained trans…

Cited by 0SourceScholar
2023

Dual-Attention Neural Transducers for Efficient Wake Word Spotting in Speech Recognition

ICASSP 2023accepted

We present dual-attention neural biasing, an architecture designed to boost Wake Words (WW) recognition and improve inference time latency on speech recognition tasks. This architecture enables a dynamic switch for its runtime compute paths by exploiting WW spotting to select which branch of its att…

Cited by 0SourceScholar
2023

Gated Contextual Adapters For Selective Contextual Biasing In Neural Transducers

ICASSP 2023accepted

Neural contextual biasing for end-to-end neural ASR transducers has shown significant improvements in the recognition of named entities, such as contact names or device names. However, it comes with the cost of increased compute, as the biasing layers (which are usually based on cross-attention) add…

Cited by 0SourceScholar
2023

Lookahead When It Matters: Adaptive Non-causal Transformers for Streaming Neural Transducers

ICML 2023poster

Streaming speech recognition architectures are employed for low-latency, real-time applications. Such architectures are often characterized by their causality. Causal architectures emit tokens at each frame, relying only on current and past signal, while non-causal models are exposed to a window of…

Cited by 9SourcePDFScholar
2023

Multilingual End-To-End Spoken Language Understanding For Ultra-Low Footprint Applications

ICASSP 2023accepted

Tiny Signal-to-Interpretation (TinyS2I) has been recently introduced as an ultra low-footprint end-to-end spoken language understanding (SLU) model. This architecture is capable of running in ultra resource constrained environments like voice assistant devices, while at the same time reducing latenc…

Cited by 0SourceScholar
2023

Robust Acoustic And Semantic Contextual Biasing In Neural Transducers For Speech Recognition

ICASSP 2023accepted

Attention-based contextual biasing approaches have shown significant improvements in the recognition of generic and/or personal rare-words in End-to-End Automatic Speech Recognition (E2E ASR) systems like neural transducers. These approaches employ crossattention to bias the model towards specific c…

Cited by 0SourceScholar
2022

A Neural Prosody Encoder for End-to-End Dialogue Act Classification

ICASSP 2022accepted

Dialogue act classification (DAC) is a critical task for spoken language understanding in dialogue systems. Prosodic features such as energy and pitch have been shown to be useful for DAC. Despite their importance, little research has explored neural approaches to integrate prosodic features into en…

Cited by 0SourceScholar
2022

Caching Networks: Capitalizing on Common Speech for ASR

ICASSP 2022accepted

We introduce Caching Networks (CachingNets), a speech recognition network architecture capable of delivering faster, more accurate decoding by leveraging common speech patterns. By explicitly incorporating select sentences unique to each user into the network’s design, we show how to train the model…

Cited by 0SourceScholar
2022

Contextual Adapters for Personalized Speech Recognition in Neural Transducers

ICASSP 2022accepted

Personal rare word recognition in end-to-end Automatic Speech Recognition (E2E ASR) models is a challenge due to the lack of training data. A standard way to address this issue is with shallow fusion methods at inference time. However, due to their dependence on external language models and the dete…

Cited by 0SourceScholar
2022

TINYS2I: A Small-Footprint Utterance Classification Model with Contextual Support for On-Device SLU

ICASSP 2022accepted

On-device spoken language understanding (SLU) offers the potential for significant latency savings compared to cloud-based processing, as the audio stream does not need to be transmitted to a server. We present Tiny Signal-to-interpretation (TinyS2I), an end-to-end on-device SLU approach which is fo…

Cited by 0SourceScholar
2022

Tie Your Embeddings Down: Cross-Modal Latent Spaces for End-to-end Spoken Language Understanding

ICASSP 2022accepted

End-to-end (E2E) spoken language understanding (SLU) systems can infer the semantics of a spoken utterance directly from an audio signal. However, training an E2E system remains a challenge, largely due to the scarcity of paired audio-semantics data. In this paper, we consider an E2E system as a mul…

Cited by 0SourceScholar
2021

End-to-End Multi-Channel Transformer for Speech Recognition

ICASSP 2021accepted

Transformers are powerful neural architectures that allow integrating different modalities using attention mechanisms. In this paper, we leverage the neural transformer architectures for multi-channel speech recognition systems, where the spectral and spatial information collected from different mic…

Cited by 0SourceScholar
2021

Joint ASR and Language Identification Using RNN-T: An Efficient Approach to Dynamic Language Switching

ICASSP 2021accepted

Conventional dynamic language switching enables seamless multilingual interactions by running several monolingual ASR systems in parallel and triggering the appropriate downstream components using a standalone language identification (LID) service. Since this solution is neither scalable nor cost- a…

Cited by 0SourceScholar
2021

Sparsification via Compressed Sensing for Automatic Speech Recognition

ICASSP 2021accepted

In order to achieve high accuracy for machine learning (ML) applications, it is essential to employ models with a large number of parameters. Certain applications, such as Automatic Speech Recognition (ASR), however, require real-time interactions with users, hence compelling the model to have as lo…

Cited by 0SourceScholar
2020

Multilingual Grapheme-To-Phoneme Conversion with Byte Representation

ICASSP 2020accepted

Grapheme-to-phoneme (G2P) models convert a written word into its corresponding pronunciation and are essential components in automatic-speech-recognition and text-to-speech systems. Recently, the use of neural encoder-decoder architectures has substantially improved G2P accuracy for mono- and multi-…

Cited by 0SourceScholar
2018

Normalization of Partly Overlapping Audio Recordings from the Same Event Based on Relative Signal Powers

ICASSP 2018accepted

Exploiting correlations in the audio, several works in the past have demonstrated the ability to automatically match and synchronize user-generated video or audio files of the same event. Such tools solve for the unknown starting and ending time of each available recording along the event time-line…

Cited by 0SourceScholar
2017

Automatic matching and synchronization of user generated videos from a large scale sport event

ICASSP 2017accepted

Exploiting correlations in the audio, several works in the past have demonstrated the ability to automatically match and synchronize User Generated Video (UGV) files of the same event. In this paper, we focus on the challenging acoustic environment of a large scale athletic event. We show that the c…

Cited by 0SourceScholar
2017

DOA estimation with histogram analysis of spatially constrained active intensity vectors

ICASSP 2017accepted

The active intensity vector (AIV) is a common descriptor of the sound field. In microphone array processing, AIV is commonly approximated with beamforming operations and utilized as a direction of arrival (DOA) estimator. However, in its original form, it provides inaccurate estimates in sound field…

Cited by 0SourceScholar
2017

Towards wireless acoustic sensor networks for location estimation and counting of multiple speakers in real-life conditions

ICASSP 2017accepted

Speaker localization and counting in real-life conditions remains a challenging task. The computational burden, transmission usage and synchronization issues pose several limitations. Moreover, the physical characteristics of real speakers in terms of directivity pattern and orientation, as well as…

Cited by 0SourceScholar
2016

3D DOA estimation of multiple sound sources based on spatially constrained beamforming driven by intensity vectors

ICASSP 2016accepted

Sound source localization in three dimensions with microphone arrays is an active field of research, applicable in sound enhancement, source separation, and sound field analysis. In this contribution we propose a method for three dimensional multiple sound source localization in reverberant environm…

Cited by 0SourceScholar
2015

Foreground suppression for capturing and reproduction of crowded acoustic environments

ICASSP 2015accepted

Traditionally, sensor arrays and spatial filtering aim to enhance individual sources by suppressing ambient noise and reverberation. In this paper, the exactly opposite problem is examined, that of suppressing individual sources in favour of the ambient sound and of the whole acoustic scene in gener…

Cited by 0SourceScholar