42 research outputs found
Evolutionary discriminative confidence estimation for spoken term detection
The final publication is available at Springer via http://dx.doi.org/10.1007/s11042-011-0913-zSpoken term detection (STD) is the task of searching for occurrences
of spoken terms in audio archives. It relies on robust confidence estimation
to make a hit/false alarm (FA) decision. In order to optimize the decision
in terms of the STD evaluation metric, the confidence has to be discriminative.
Multi-layer perceptrons (MLPs) and support vector machines (SVMs) exhibit
good performance in producing discriminative confidence; however they are
severely limited by the continuous objective functions, and are therefore less
capable of dealing with complex decision tasks. This leads to a substantial
performance reduction when measuring detection of out-of-vocabulary (OOV)
terms, where the high diversity in term properties usually leads to a complicated
decision boundary.
In this paper we present a new discriminative confidence estimation approach
based on evolutionary discriminant analysis (EDA). Unlike MLPs and
SVMs, EDA uses the classification error as its objective function, resulting
in a model optimized towards the evaluation metric. In addition, EDA combines
heterogeneous projection functions and classification strategies in decision
making, leading to a highly flexible classifier that is capable of dealing
with complex decision tasks. Finally, the evolutionary strategy of EDA reduces the risk of local minima. We tested the EDA-based confidence with a
state-of-the-art phoneme-based STD system on an English meeting domain
corpus, which employs a phoneme speech recognition system to produce lattices
within which the phoneme sequences corresponding to the enquiry terms
are searched. The test corpora comprise 11 hours of speech data recorded with
individual head-mounted microphones from 30 meetings carried out at several
institutes including ICSI; NIST; ISL; LDC; the Virginia Polytechnic Institute
and State University; and the University of Edinburgh. The experimental results
demonstrate that EDA considerably outperforms MLPs and SVMs on
both classification and confidence measurement in STD, and the advantage
is found to be more significant on OOV terms than on in-vocabulary (INV)
terms. In terms of classification performance, EDA achieved an equal error
rate (EER) of 11% on OOV terms, compared to 34% and 31% with MLPs and
SVMs respectively; for INV terms, an EER of 15% was obtained with EDA
compared to 17% obtained with MLPs and SVMs. In terms of STD performance
for OOV terms, EDA presented a significant relative improvement of
1.4% and 2.5% in terms of average term-weighted value (ATWV) over MLPs
and SVMs respectively.This work was partially supported by the French Ministry of Industry
(Innovative Web call) under contract 09.2.93.0966, ‘Collaborative Annotation for Video
Accessibility’ (ACAV) and by ‘The Adaptable Ambient Living Assistant’ (ALIAS) project
funded through the joint national Ambient Assisted Living (AAL) programme
On Distant Speech Recognition for Home Automation
The official version of this draft is available at Springer via http://dx.doi.org/10.1007/978-3-319-16226-3_7International audienceIn the framework of Ambient Assisted Living, home automation may be a solution for helping elderly people living alone at home. This study is part of the Sweet-Home project which aims at developing a new home automation system based on voice command to improve support and well-being of people in loss of autonomy. The goal of the study is vocal order recognition with a focus on two aspects: distance speech recognition and sentence spotting. Several ASR techniques were evaluated on a realistic corpus acquired in a 4-room flat equipped with microphones set in the ceiling. This distant speech French corpus was recorded with 21 speakers who acted scenarios of activities of daily living. Techniques acting at the decoding stage, such as our novel approach called Driven Decoding Algorithm (DDA), gave better speech recognition results than the baseline and other approaches. This solution which uses the two best SNR channels and a priori knowledge (voice commands and distress sentences) has demonstrated an increase in recognition rate without introducing false alarms
Fat, fibre and cancer risk in African Americans and rural Africans
Rates of colon cancer are much higher in African Americans (65: 100,000) than in rural South Africans (Peer reviewe
Fat, fibre and cancer risk in African Americans and rural Africans
Rates of colon cancer are much higher in African Americans (65: 100,000) than in rural South Africans (Peer reviewe
Targeted therapy of short-bowel syndrome with teduglutide: the new kid on the block
Kishore Vipperla,1 Stephen J O'Keefe2 1Division of General Internal Medicine, University of Pittsburgh Medical Center, 2Division of Gastroenterology, Hepatology, and Nutrition, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA Abstract: Extensive intestinal resection impairs the absorptive capacity and results in short-bowel syndrome-associated intestinal failure (SBS-IF), when fluid, electrolyte, acid-base, micro-, and macronutrient homeostasis cannot be maintained on a conventional oral diet. Several factors, including the length and site of the resected intestine, anatomical conformation of the remnant bowel, and the degree of postresection intestinal adaptation determine the disease severity. While mild SBS patients achieve nutritional autonomy with dietary modification (eg, hyperphagia, small frequent meals, and oral rehydration fluids), those with moderate-to-severe disease may develop SBS-IF and become dependent on parenteral support (PS) in the form of intravenous fluids and/or nutrition for sustenance of life. SBS-IF is a chronic debilitating disease associated with a poor quality of life, and carries significant morbidity and health care costs. Medical management of SBS-IF is primarily focused on individually tailored symptomatic treatment strategies, such as antisecretory and antidiarrheal agents to mitigate fluid losses, and PS. However, PS administration is associated with potentially life-threatening complications, such as central venous thromboses, bloodstream infections, and liver disease. In pursuit of a targeted therapy to augment intestinal adaptation, research over the past 2 decades has identified glucagon-like peptide, an intestinotrophic gut peptide that has been shown to enhance intestinal absorptive capacity by causing an increase in the villus length, crypt depth, and mesenteric blood flow and by decreasing gastrointestinal motility and secretions. Teduglutide, a recombinant analog of glucagon-like peptide-2, is the first targeted therapeutic agent to gain approval for use in adult SBS-IF. Teduglutide was shown to result in significant (20%–100%) reduction in PS-volume requirement and have a satisfactory safety profile in three randomized control trials. Further research is warranted to see if reduction in PS dependency translates to improved quality of life and reduced PS-associated complications. Keywords: short-gut syndrome, intestinal adaptation, glucagon-like peptide-2, teduglutid