Decimative Spectral Estimation with Unconstrained Model Order

This paper presents a new state-space method for spectral estimation that performs decimation by any factor, it makes use of the full set of data and brings further apart the poles under consideration, while imposing almost no constraints to the size of the Hankel matrix (model order), as decimation increases. It is compared against two previously proposed techniques for spectral estimation (along with derived decimative versions), that lie among the most promising methods in the field of spectroscopy, where accuracy of parameter estimation is of utmost importance. Moreover, it is compared against a state-of-the-art purely decimative method proposed in literature. Experiments performed on simulated NMR signals prove the new method to be more robust, especially for low signal-to-noise ratio

Multipurpose Design of Greek Sign Language Resources: A factor towards Universal Access

Abstract. In this paper we present the methodology of data collection and implementation of databases for the creation of extensive lexical and terminological resources for the Greek Sign Language (GSL) in order to introduce the major issue of dynamic sign representation. In respect to electronic linguistic resources of GSL, the focus is on issues of validation of linguistic content, multipurpose design and reusability of created resources, exemplified by the multimedia dictionary products of the projects NOEMA (1999-2001) and PROKLISI (2002-2004). In relation to sign representation, we discuss the use of video as a restricted means of reproducing linguistic content uttered in the three-dimensional space and present an attempt to use avatar and animation technologies, along with exploitation of electronic linguistic resources of the Greek Sign Language (GSL), in order to provide a dynamic device of generating unrestricted sign sequences. The aim is to set up a sign generation mechanism for the Greek Sign Language by means of a virtual human signer (avatar) that can be adaptable to various platforms. The overall emphasis is placed on exploitation of Universal Access and Design for All principles that allow proactive system architectures instead of a-posteriori adaptations.

Gesture and Sign Language in Human-Computer Interaction and Embodied Communication9th International Gesture Workshop, GW 2011, Athens, Greece, May 25-27, 2011, Revised Selected Papers /

XIV, 275 p. 122 illus.online resource

User Evaluation of the MOBOT Rollator Type Robotic Mobility Assistive Device

In this paper, we report on the evaluation strategy and the results that were obtained from the final end-user evaluation process of an innovative robotic assistive device supporting mobility. More specifically, the paper deals with the evaluation of the MOBOT robotic rollator as regards to the system’s overall performance and its individual assistive characteristics and functionalities, as implemented in respect to (i) the provided cognitive assistance, and (ii) the adopted audio-gestural human-robot communication model. User evaluation was designed on the basis of an extensive survey of scales and methodologies widely reported in the relevant literature. The actual evaluation phase exploited the QUEST 2.0, ATDPA-Device Form, and PYTHEIA scales to measure the subjective satisfaction of the users. The PYTHEIA scale, in particular, was structured in order to fill the gaps that were identified during the study of previously existing tools for measuring assistive device user satisfaction. The scale was applied for the first time during the reported evaluation process. An analysis of the results showed that MOBOT was ranked very high by end users in all of the aspects addressed by the three employed assessment scales, thus providing significant evidence for positive acceptance of any industrialized outcome of the current prototype in the assistive robots market