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Neural sequence-to-sequence systems deliver state-of-the-art performance for automatic speech recognition. When using appropriate modeling units, e.g., byte-pair encoding, these systems are in principle open vocabulary systems. In practice,…

Computation and Language · Computer Science 2026-03-05 Christian Huber , Alexander Waibel

The objective of Aspect Based Sentiment Analysis is to capture the sentiment of reviewers associated with different aspects. However, complexity of the review sentences, presence of double negation and specific usage of words found in…

Computation and Language · Computer Science 2022-02-15 Abir Chakraborty

In this paper we consider the dictionary learning problem for sparse representation. We first show that this problem is NP-hard by polynomial time reduction of the densest cut problem. Then, using successive convex approximation strategies,…

Machine Learning · Computer Science 2015-11-06 Meisam Razaviyayn , Hung-Wei Tseng , Zhi-Quan Luo

High-contrast imaging for the detection and characterization of exoplanets relies on the instrument's capability to block out the light of the host star. Some current post-processing methods for calibrating out the residual speckles use…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Marie Ygouf , Laurent M. Mugnier , David Mouillet , Thierry Fusco , Jean-Luc Beuzit

We introduce Diffusion Active Learning, a novel approach that combines generative diffusion modeling with data-driven sequential experimental design to adaptively acquire data for inverse problems. Although broadly applicable, we focus on…

Machine Learning · Computer Science 2025-04-07 Luis Barba , Johannes Kirschner , Tomas Aidukas , Manuel Guizar-Sicairos , Benjamín Béjar

We consider the problem of recognizing a vocabulary--a collection of words (sequences) over a finite alphabet--from a potential subsequence of one of its words. We assume the given subsequence is received through a deletion channel as a…

Information Theory · Computer Science 2009-04-23 Majid Fozunbal

Estimation of optical aberrations from volumetric intensity images is a key step in sensorless adaptive optics for 3D microscopy. Recent approaches based on deep learning promise accurate results at fast processing speeds. However,…

Image and Video Processing · Electrical Eng. & Systems 2020-10-28 Debayan Saha , Uwe Schmidt , Qinrong Zhang , Aurelien Barbotin , Qi Hu , Na Ji , Martin J. Booth , Martin Weigert , Eugene W. Myers

Spectral computed tomography (CT) has a great superiority in lesion detection, tissue characterization and material decomposition. To further extend its potential clinical applications, in this work, we propose an improved tensor dictionary…

Computer Vision and Pattern Recognition · Computer Science 2018-07-25 Weiwen Wu , Yanbo Zhang , Qian Wang , Fenglin Liu , Peijun Chen , Hengyong Yu

Illuminant estimation aims to infer scene illumination from image measurements despite intrinsic ambiguities between surface reflectance and lighting. Most existing methods operate on trichromatic RGB images and are therefore fundamentally…

Computer Vision and Pattern Recognition · Computer Science 2026-05-14 G. Dofri Vidarsson , Liying Lu , Sabine Süsstrunk

Speckle patterns produced by coherent X-ray have a close relationship with the internal structure of materials but quantitative inversion of the relationship to determine structure from speckle patterns is challenging. Here, we investigate…

Sparse representation, which uses dictionary atoms to reconstruct input vectors, has been studied intensively in recent years. A proper dictionary is a key for the success of sparse representation. In this paper, an active dictionary…

Computer Vision and Pattern Recognition · Computer Science 2014-09-30 Jin Xu , Haibo He , Hong Man

Material decomposition for imaging multiple contrast agents in a single acquisition has been made possible by spectral CT: a modality which incorporates multiple photon energy spectral sensitivities into a single data collection. This work…

Medical Physics · Physics 2020-08-11 Matthew Tivnan , Steven Tilley , J. Webster Stayman

Blur in X-ray radiographs not only reduces the sharpness of image edges but also reduces the overall contrast. The effective blur in a radiograph is the combined effect of blur from multiple sources such as the detector panel, X-ray source…

Image and Video Processing · Electrical Eng. & Systems 2020-09-08 K. Aditya Mohan , Robert M. Panas , Jefferson A. Cuadra

With the growing technology of photon-counting detectors (PCD), spectral CT is a widely concerned topic which has the potential of material differentiation. However, due to some non-ideal factors such as cross talk and pulse pile-up of the…

Medical Physics · Physics 2020-07-21 Ao Zheng , Hongkai Yang , Li Zhang , Yuxiang Xing

X-ray Absorption Spectroscopy (XAS) is a powerful technique for probing local atomic environments, yet its interpretation remains limited by the need for expert-driven analysis, computationally expensive simulations, and element-specific…

Machine Learning · Computer Science 2025-08-27 Yufeng Wang , Peiyao Wang , Lu Wei , Lu Ma , Yuewei Lin , Qun Liu , Haibin Ling

These notes offer a unified introduction to spectral methods for the study of complex systems. They are intended as an operative manual rather than a theorem-proof textbook: the emphasis is on tools, identities, and perspectives that can be…

Statistical Mechanics · Physics 2025-09-10 Francesco Caravelli

Dictionary learning algorithms have been successfully used in both reconstructive and discriminative tasks, where the input signal is represented by a linear combination of a few dictionary atoms. While these methods are usually developed…

Machine Learning · Statistics 2015-02-12 Soheil Bahrampour , Nasser M. Nasrabadi , Asok Ray , Kenneth W. Jenkins

There are several issues with the existing general machine translation or natural language generation evaluation metrics, and question-answering (QA) systems are indifferent in that context. To build robust QA systems, we need the ability…

Computation and Language · Computer Science 2022-07-06 Farida Mustafazade , Peter F. Ebbinghaus

Speech recognition systems for irregularly-spelled languages like English normally require hand-written pronunciations. In this paper, we describe a system for automatically obtaining pronunciations of words for which pronunciations are not…

Computation and Language · Computer Science 2017-06-13 Xiaohui Zhang , Vimal Manohar , Daniel Povey , Sanjeev Khudanpur

Cross-lingual text representations have gained popularity lately and act as the backbone of many tasks such as unsupervised machine translation and cross-lingual information retrieval, to name a few. However, evaluation of such…

Computation and Language · Computer Science 2021-05-12 Mikhail Fain , Niall Twomey , Danushka Bollegala