Fuzzy reasoning in confidence evaluation of speech recognition

Confidence measures represent a systematic way to express reliability of speech recognition results. A common approach to confidence measuring is to take profit of the information that several recognition-related features offer and to combine them, through a given compilation mechanism , into a more effective way to distinguish between correct and incorrect recognition results. We propose to use a fuzzy reasoning scheme to perform the information compilation step. Our approach opposes the previously proposed ones because ours treats the uncertainty of recognition hypotheses in terms ofPeer ReviewedPostprint (published version

Language modeling using X-grams

In this paper, an extension of n-grams, called x-grams, is proposed. In this extension, the memory of the model (n) is not fixed a priori. Instead, large memories are accepted first, and merging criteria are then applied to reduce the complexity and to ensure reliable estimations. The results show how the perplexity obtained with x-grams is smaller than that of n-grams. Furthermore, the complexity is smaller than trigrams and can become close to bigrams.Peer ReviewedPostprint (published version

A second opinion approach for speech recognition verification

In order to improve the reliability of speech recognition results, a verifying system, that takes profit of the information given from an alternative recognition step is proposed. The alternative results are considered as a second opinion about the nature of the speech recognition process. Some features are extracted from both opinion sources and compiled, through a fuzzy inference system, into a more discriminant confidence measure able to verify correct results and disregard wrong ones. This approach is tested in a keyword spotting task taken form the Spanish SpeechDat database. Results show a considerable reduction of false rejections at a fixed false alarm rate compared to baseline systems.Peer ReviewedPostprint (published version

Contextual confidence measures for continuous speech recognition

This paper explores the repercussion of contextual information into confidence measuring for continuous speech recognition results. Our approach comprises three steps: to extract confidence predictors out of recognition results, to compile those predictors into confidence measures by means of a fuzzy inference system whose parameters have been estimated, directly from examples, with an evolutionary strategy and, finally, to upgrade the confidence measures by the inclusion of contextual information. Through experimentation with two different continuous speech application tasks, results show that the context re-scoring procedure improves the capabilities of confidence measures to discriminate between correct and incorrect recognition results for every level of thresholding, even when a rather simple method to add contextual information is considered.Peer ReviewedPostprint (published version

TESTING OF THE NEW USGS K INDEX ALGORITHM AT BEAR LAKE

The K index was developed by Bartels in 1939 as an estimate of the level of geomagnetic activity caused by the Sun. This index was computed manually every three hours at geomagnetic observatories using the magnetic traces of the surface planetary magnetic field. In 1991, the International Association of Geomagnetism and Aeronomy approved four additional methods to compute the K index; all of them were computer algorithms. One of the approved methods, the Wilson code, recently underwent some modifications. The new algorithm is now part of a Windows-based computer program being developed by the United States Geological Survey (USGS). After successfully evaluating a beta version of this new program, it was used to compute the K index for a new location. This new location is the Bear Lake Observatory (BLO), where the Utah State University has been collecting geomagnetic data from their magnetometer. Statistical techniques were applied to correlate K indices among existing stations in an effort to develop a test for the validity of the K index of a station. These statistical tests were applied to the BLO K index proving that the technique works and that the BLO K index was computed properly

Metodología de elaboración de materiales didácticos multimedia accesibles

Los contenidos didácticos adquieren una importante relevancia en la modalidad e-learning ya que, en gran medida, de ellos depende el éxito del aprendizaje del alumnado. Para facilitar la elaboración de estos materiales multimedia, y garantizar que estén diseñados atendiendo a criterios pedagógicos y de accesibilidad, la Fundación Andaluza Fondo de Formación y Empleo ha desarrollado una metodología de trabajo. En esta contribución se presenta dicha metodología y los instrumentos desarrollados para el desarrollo de cada una de sus fases: Diseño del material didáctico, Elaboración de contenidos y Maquetación multimedia. Dentro de cada una de las fases se aportan orientaciones y plantillas. Así, en la fase de Elaboración de contenidos, que conlleva la Redacción y Guionización, se incorporan pautas para el desarrollo y la elaboración de los manuales PDF y modelos de guiones para cada tipo de pantalla. En la fase de Maquetación, que conlleva la creación de los archivos multimedia que formarán el curso basados en los guiones elaborados en la fase II, se aportan plantillas de cada una de las pantallas y elementos que la componen.Didactic contents acquire an important significance in e-learning since the success of the students learning depends largely on them. In order to facilitate the development of these multimedia materials, as well as to ensure they are designed according to educational and accessibility criteria, the Fundación Andaluza Fondo de Formación y Empleo has developed a working methodology. On the basis of this contribution the methodology and instruments developed for implementation of each phase: Design of learning materials, Content development and multimedia DTP. Within each phase some guidance and templates are provided. Thus, in the Content development phase (which involves Writing and Scripting) guidelines for the development and elaboration of the PDF manuals as well as script models for each type of display are incorporated. In the DTP or Layout phase, involving the creation of multimedia files that will shape the training course itself according to scripts developed in Phase II, templates for each type of display and different component parts are also provided

Skills that Pre-service Primary Teachers’ consider important in argumentation approach

Argumentation as a form of scientific discourse is a powerful tool that allows students questioning, justifying, and evaluating their and others’ claims. In science education, transmissive teaching predominates and this leads to difficulties in students’ construction of arguments and highlights limitations in teachers' pedagogical abilities in the management of this type of activities. Also, teachers' beliefs and perceptions have a big influence in the way they teach. Thus, the purpose has been to investigate pre-service primary teachers’ beliefs of what would be the skills they need as a core to support argumentation in science classrooms, and what skills students can develop when participate in science lessons based in argumentation. Results show that Pre-service Teachers of Primary pay little attention to the skills they will need in order to manage different methodological strategies as debate, pair work or pair discussion, that support the argumentation approach. Moreover, they lack of awareness about what is a good argument and its components, besides scientific knowledge. These results are significant because they indicate a need in designing specific training programs to support teachers in acquiring knowledge and skills about argumentation.Campus de Excelencia Internacional Andalucía Tech. This study is part of the project “La argumentacıón como estrategıa metodológıca para el desarrollo de competencıas profesıonales docentes.” [Argumentation as a methodological strategy for the development of professional teacher competences] (PIE15-74) funded by the University of Málaga in the assembly of 201

Extending F10.7\u27s Time Resolution to Capture Solar Flare Phenomena

Solar ultraviolet (UV) radiation ionizes the neutral components in the atmosphere, which is partly responsible for the formation of the ionosphere, and contributes to heating of the atmosphere. Solar flares change the solar spectrum at times by several orders of magnitude. These changes modify the Earth\u27s upper atmosphere, causing problems to communication systems and space operations, such as increased satellite drag. Unfortunately, solar UV measurements are limited since they can only be observed with space-based sensors. In order to work around this limitation, the solar radio emissions at a wavelength of 10.7 cm have been used as a proxy for the solar UV radiation. These measurements, known as the F10.7 index, are a snapshot of the solar activity at the time they are taken and do not capture the changes that occur throughout the day, such as flares. In order to capture this daily variation, we used 1-second cadence solar radio data and compared it to solar UV measurements taken once per orbit by the TIMED satellite. We found significant correlations between some radio frequencies and different UV wavelengths during quiet times. These correlations changed in terms of radio frequency and UV wavelength during solar flares