17 research outputs found
Automatic localization and diagnosis of pronunciation errors for second-language learners of English
Get PDFAn automatic system for detection of pronunciation errors by adult learners of English is embedded in a language–learning package. Four main features are: (1) a recognizer robust to non–native speech; (2) localization of phone– and word–level errors; (3) diagnosis of what sorts of phone–level errors took place; and (4) a lexical–stress detector. These tools together allow robust, consistent, and specific feedback on pronunciation errors, unlike many previous systems that provide feedbaconly at a more general level. The diagnosis technique searches for errors expected based on the student’s mother tongue and uses a separate bias for each error in order to maintain a particular desired global false alarm rate. Results are presented here for non–native recognition on tasks of differing complexity and for diagnosis, based on a data set of artificial errors, showing that this method can detect many contrasts with a high hit rate and a low false alarm rate
Supercalcolo: mito o realtà
No full textQuesto volume, dedicato ai supercalcolatori e al calcolo parallelo, offre una panoramica degli strumenti di calcolo che ora chiamiamo supercalcolatori e immaginiamo come strumenti potentissimi ma essenzialmente di élite
Knowledge-Based Multi-Criteria Optimization to Support Indoor Positioning
No full textIndoor position estimation constitutes a central task in home-based assisted living environments. Such environments often rely on a heterogeneous collection of low-cost sensors whose diversity and lack of precision has to be compensated by advanced techniques for localization and tracking. Although there are well established quantitative methods in robotics and neighboring fields for addressing these problems, they lack advanced knowledge representation and reasoning capacities. Such capabilities are not only useful in dealing with heterogeneous and lacking information but moreover they allow for a better inclusion of semantic information and more general homecare and patient-related knowledge. We address this problem and investigate how state-of-theart localization and tracking methods can be combined with answer set programming, as a popular knowledge representation and reasoning formalism. We report upon a case-study and provide a first experimental evaluation of knowledge-based position estimation.
