{"603530":{"#nid":"603530","#data":{"type":"event","title":"DCL Seminar Series: Dr. Anthony Yezzi","body":[{"value":"\u003Cp\u003EFollowing the seminal work of Nesterov, accelerated optimization methods\u0026nbsp;\u003Cbr \/\u003E\r\n(sometimes referred to as momentum methods) have been used to powerfully\u0026nbsp;\u003Cbr \/\u003E\r\nboost the performance of first-order, gradient-based parameter\u0026nbsp;\u003Cbr \/\u003E\r\nestimation in scenarios were second-order optimization strategies are\u0026nbsp;\u003Cbr \/\u003E\r\neither inapplicable or impractical. Not only does accelerated gradient\u0026nbsp;\u003Cbr \/\u003E\r\ndescent converge considerably faster than traditional gradient descent,\u0026nbsp;\u003Cbr \/\u003E\r\nbut it performs a more robust local search of the parameter space by\u0026nbsp;\u003Cbr \/\u003E\r\ninitially overshooting and then oscillating back as it settles into a\u0026nbsp;\u003Cbr \/\u003E\r\nfinal configuration, thereby selecting only local minimizers with a\u0026nbsp;\u003Cbr \/\u003E\r\nattraction basin large enough to accommodate the initial overshoot. This\u0026nbsp;\u003Cbr \/\u003E\r\nbehavior has made accelerated search methods particularly popular within\u0026nbsp;\u003Cbr \/\u003E\r\nthe machine learning community where stochastic variants have been\u0026nbsp;\u003Cbr \/\u003E\r\nproposed as well.\u0026nbsp; So far, however, accelerated optimization methods\u0026nbsp;\u003Cbr \/\u003E\r\nhave been applied to searches over finite parameter spaces. We show how\u0026nbsp;\u003Cbr \/\u003E\r\na variational framework for these finite dimensional methods (recently\u0026nbsp;\u003Cbr \/\u003E\r\nformulated by Wibisono, Wilson, and Jordan) can be extended to the\u0026nbsp;\u003Cbr \/\u003E\r\ninfinite dimensional setting and, in particular, to the manifold of\u0026nbsp;\u003Cbr \/\u003E\r\nplanar curves in order to yield a new class of accelerated geometric,\u0026nbsp;\u003Cbr \/\u003E\r\nPDE-based active contours.\u003C\/p\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"DCL Seminar Series Presents Anthony Yezzi"}],"uid":"34578","created_gmt":"2018-03-08 18:02:56","changed_gmt":"2018-03-08 18:02:56","author":"awatson46","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2018-03-16T12:00:00-04:00","event_time_end":"2018-03-16T13:00:00-04:00","event_time_end_last":"2018-03-16T13:00:00-04:00","gmt_time_start":"2018-03-16 16:00:00","gmt_time_end":"2018-03-16 17:00:00","gmt_time_end_last":"2018-03-16 17:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"66191","name":"Decision and Control Lab (DCL)"}],"categories":[],"keywords":[{"id":"1808","name":"graduate students"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"78771","name":"Public"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}