2,614 research outputs found
Personalized Acoustic Modeling by Weakly Supervised Multi-Task Deep Learning using Acoustic Tokens Discovered from Unlabeled Data
It is well known that recognizers personalized to each user are much more
effective than user-independent recognizers. With the popularity of smartphones
today, although it is not difficult to collect a large set of audio data for
each user, it is difficult to transcribe it. However, it is now possible to
automatically discover acoustic tokens from unlabeled personal data in an
unsupervised way. We therefore propose a multi-task deep learning framework
called a phoneme-token deep neural network (PTDNN), jointly trained from
unsupervised acoustic tokens discovered from unlabeled data and very limited
transcribed data for personalized acoustic modeling. We term this scenario
"weakly supervised". The underlying intuition is that the high degree of
similarity between the HMM states of acoustic token models and phoneme models
may help them learn from each other in this multi-task learning framework.
Initial experiments performed over a personalized audio data set recorded from
Facebook posts demonstrated that very good improvements can be achieved in both
frame accuracy and word accuracy over popularly-considered baselines such as
fDLR, speaker code and lightly supervised adaptation. This approach complements
existing speaker adaptation approaches and can be used jointly with such
techniques to yield improved results.Comment: 5 pages, 5 figures, published in IEEE ICASSP 201
MATEX: A Distributed Framework for Transient Simulation of Power Distribution Networks
We proposed MATEX, a distributed framework for transient simulation of power
distribution networks (PDNs). MATEX utilizes matrix exponential kernel with
Krylov subspace approximations to solve differential equations of linear
circuit. First, the whole simulation task is divided into subtasks based on
decompositions of current sources, in order to reduce the computational
overheads. Then these subtasks are distributed to different computing nodes and
processed in parallel. Within each node, after the matrix factorization at the
beginning of simulation, the adaptive time stepping solver is performed without
extra matrix re-factorizations. MATEX overcomes the stiff-ness hinder of
previous matrix exponential-based circuit simulator by rational Krylov subspace
method, which leads to larger step sizes with smaller dimensions of Krylov
subspace bases and highly accelerates the whole computation. MATEX outperforms
both traditional fixed and adaptive time stepping methods, e.g., achieving
around 13X over the trapezoidal framework with fixed time step for the IBM
power grid benchmarks.Comment: ACM/IEEE DAC 2014. arXiv admin note: substantial text overlap with
arXiv:1505.0669
Regioselective One-pot Protection and Protection-glycosylation of Carbohydrates
Deciphering the roles and structure–activity relationships of carbohydrates in biological processes requires access to sugar molecules of confirmed structure and high purity. Chemical synthesis is one of the best ways to obtain such access. However, the synthesis of carbohydrates
has long been impeded by two major challenges – the regioselective protection of the polyol moiety of each monosaccharide building block and the stereoselective glycosylation to produce oligosaccharides of desired length. Here, we review the development of the first regioselective protection-glycosylation
and a revolutionary regioselective combinatorial one-pot protection of monosaccharides that can be used to differentiate the various hydroxy groups of monosaccharides with a vast array of orthogonal protective groups in one-pot procedures
Palpation of preoperatively inserted indwelling angiocatheter facilitates intraoperative localization of obscure gastrointestinal bleeding of small intestinal origin
SummaryBackgroundPalpation of the indwelling angiographic catheter inserted before operation to localize obscure gastrointestinal bleeding of small intestinal origin during laparotomy has rarely been reported in the literature.PurposeThe purpose of the study is to investigate the role of palpable indwelling angiocatheter inserted before operation in localizing obscure gastrointestinal bleeding of small intestinal origin during laparotomy.MethodsBetween January 2003 and December 2010, seven patients who had a clinical impression of obscure gastrointestinal bleeding of small intestinal origin and angiographic extravasation from the mesenteric artery had an angiocatheter inserted into the distal mesenteric branch. During laparotomy the catheter was palpated to guide subsequent resection of the intestine. The clinical outcomes of these patients were retrospectively reviewed.ResultsDuring laparotomy the retained catheter failed to be palpated in one patient. Six patients underwent segmental resection of intestine under guidance of the palpated catheter. All six patients had positive identification of small bowel bleeding. The yield rate of intraoperative localization was 86% (6 out of 7). Two of the six patients ceased bleeding after operation, but died of underlying disease progression. Four of the six patients had an uneventful postoperative clinical course without recurrent bleeding after a median follow-up period of 25 months.ConclusionPalpation of the indwelling angiographic catheter selectively left before operation is effective for precisely locating obscure gastrointestinal bleeding of small intestinal origin during laparotomy
La adquisición del tiempo-aspecto en español en L3 para los aprendices taiwaneses
The purpose of this study was to investigate the inter-language development of the Spanish past tense by Taiwanese learners who learned Spanish as a second foreign language. The analysis of this study was based on the Lexical Aspect Hypothesis, which focuses on the inherent lexical aspect of verbs. We came to the following conclusions. (1) Taiwanese learners, whose first language was Mandarin Chinese, demonstrated more accurate uses of the Spanish preterite than the imperfect in written texts at their early stages of development. The acquisition of the lexical aspects of verbs in the preterite in terms of lexical aspect demonstrated the following order: achievement + accomplishment, activity and finally stative, whereas the acquisition of the imperfect showed the opposite sequence. (2) In the majority of the cases, the Taiwanese learners of Spanish demonstrated a similar pattern of acquisition of the Spanish past tense in terms of lexical aspect as that of English-speaking learner of Spanish. This paper will end with discussions on pedagogical implications of the findings and we hope this study will shed light on the current research on the second language acquisition of the Spanish tense/aspect.Este trabajo tiene como fin investigar el desarrollo de los tiempos pasados en la interlengua de los aprendices taiwaneses que aprenden español como segunda lengua extranjera. El análisis se basa en la Hipótesis de Aspecto Léxico que se centra en la importancia del aspecto léxico de los verbos. Llegamos a las siguientes conclusiones: (1) los aprendices taiwaneses de español cuya lengua materna es chino-mandarín manejan el pretérito mejor que el imperfecto en la producción escrita de los niveles iniciales de aprendizaje, el desarrollo de adquisición del pretérito indefinido es de acuerdo al siguiente orden: estado, actividad y realización+logro, mientras que para la adquisición del imperfecto los estudiantes siguen un orden contrario. (2) En la mayoría de los casos los aprendices taiwaneses de español siguen el mismo patrón de aprendizaje que los aprendices cuya lengua materna es el inglés en la adquisición del aspecto temporal. Por último, hacemos sugerencias pedagógicas correspondientes a las conclusiones deducidas para mejorar el resultado de aprendizaje. Con esto, esperamos que esta investigación represente una contribución al estudio relacionado con la adquisición del tiempo-aspecto en español
- …