BEGIN:VCALENDAR VERSION:2.0 PRODID:-//128.220.36.25//NONSGML kigkonsult.se iCalcreator 2.26.9// CALSCALE:GREGORIAN METHOD:PUBLISH X-FROM-URL:https://www.clsp.jhu.edu X-WR-TIMEZONE:America/New_York BEGIN:VTIMEZONE TZID:America/New_York X-LIC-LOCATION:America/New_York BEGIN:STANDARD DTSTART:20231105T020000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 RDATE:20241103T020000 TZNAME:EST END:STANDARD BEGIN:DAYLIGHT DTSTART:20240310T020000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 RDATE:20250309T020000 TZNAME:EDT END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:ai1ec-20730@www.clsp.jhu.edu DTSTAMP:20240328T164421Z CATEGORIES;LANGUAGE=en-US:Seminars CONTACT: DESCRIPTION:
Abstract
\nRaytheon BBN participated in the IARPA MATERIAL program\, whose objective is to enable rapid develop ment of language-independent methods for cross-lingual information retriev al (CLIR). The challenging CLIR task of retrieving documents written (or s poken) in one language so that they satisfy an information need expressed in a different language is exacerbated by unique challenges posed by the M ATERIAL program: limited training data for automatic speech recognition an d machine translation\, scant lexical resources\, non-standardized orthogr aphy\, etc. Furthermore\, the format of the queries and the “Query-Weighte d Value” performance measure are non-standard and not previously studied i n the IR community. In this talk\, we will describe the Raytheon BBN CLIR system\, which was successful at addressing the above challenges and uniqu e characteristics of the program.
\nBiography
\nDamianos Karakos has been at Raytheon BBN f or the past nine years\, where he is currently a Senior Principal Engineer \, Research. Before that\, he was research faculty at Johns Hopkins Univer sity. He has worked on several Government projects (e.g.\, DARPA GALE\, DA RPA RATS\, IARPA BABEL\, IARPA MATERIAL\, IARPA BETTER) and on a variety o f HLT-related topics (e.g.\, speech recognition\, speech activity detectio n\, keyword search\, information retrieval). He has published more than 60 peer-reviewed papers. His research interests lie at the intersection of h uman language technology and machine learning\, with an emphasis on statis tical methods. He obtained a PhD in Electrical Engineering from the Univer sity of Maryland\, College Park\, in 2002.
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Abstract
\n\n\n\n\nAutomatic discovery of phon e or word-like units is one of the core objectives in zero-resource speech processing. Recent attempts employ contrastive predictive coding (CPC)\, where the model learns representations by predicting the next frame given past context. However\, CPC only looks at the audio signal’s structure at the frame level. The speech structure exists beyond frame-level\, i.e.\, a t phone level or even higher. We propose a segmental contrastive predictiv e coding (SCPC) framework to learn from the signal structure at both the f rame and phone levels.\n\n\nSCPC is a hierarchical model with three stages trained in an end-to-end m anner. In the first stage\, the model predicts future feature frames and e xtracts frame-level representation from the raw waveform. In the second st age\, a differentiable boundary detector finds variable-length segments. I n the last stage\, the model predicts future segments to learn segment rep resentations. Experiments show that our model outperforms existing phone a nd word segmentation methods on TIMIT and Buckeye datasets.