Flexible system of multiple RGB-D sensors for measuring and classifying fruits in agri-food Industry

The productivity of the agri-food sector experiences continuous and growing challenges that make the use of innovative technologies to maintain and even improve their competitiveness a priority. In this context, this paper presents the foundations and validation of a flexible and portable system capable of obtaining 3D measurements and classifying objects based on color and depth images taken from multiple Kinect v1 sensors. The developed system is applied to the selection and classification of fruits, a common activity in the agri-food industry. Being able to obtain complete and accurate information of the environment, as it integrates the depth information obtained from multiple sensors, this system is capable of self-location and self-calibration of the sensors to then start detecting, classifying and measuring fruits in real time. Unlike other systems that use specific set-up or need a previous calibration, it does not require a predetermined positioning of the sensors, so that it can be adapted to different scenarios. The characterization process considers: classification of fruits, estimation of its volume and the number of assets per each kind of fruit. A requirement for the system is that each sensor must partially share its field of view with at least another sensor. The sensors localize themselves by estimating the rotation and translation matrices that allow to transform the coordinate system of one sensor to the other. To achieve this, Iterative Closest Point (ICP) algorithm is used and subsequently validated with a 6 degree of freedom KUKA robotic arm. Also, a method is implemented to estimate the movement of objects based on the Kalman Filter. A relevant contribution of this work is the detailed analysis and propagation of the errors that affect both the proposed methods and hardware. To determine the performance of the proposed system the passage of different types of fruits on a conveyor belt is emulated by a mobile robot carrying a surface where the fruits were placed. Both the perimeter and volume are measured and classified according to the type of fruit. The system was able to distinguish and classify the 95% of fruits and to estimate their volume with a 85% of accuracy in worst cases (fruits whose shape is not symmetrical) and 94% of accuracy in best cases (fruits whose shape is more symmetrical), showing that the proposed approach can become a useful tool in the agri-food industry.This project has been supported by the National Commission for Science and Technology Research of Chile (Conicyt) under FONDECYT grant 1140575 and the Advanced Center of Electrical and Electronic Engineering - AC3E (CONICYT/FB0008)

Pricing strategies and competition in the mobile broadband market

This paper analyzes mobile broadband plan prices in 37 countries between 2011 and 2014. Mobile network operators typically commercialize usage-based plans that include an access fee, a usage allowance (number of GB included in the tariff plan), and a penalty system should consumers exceed the contracted allowance. Our empirical model shows that the prices of these plans are lower than those of unlimited contracts, and that they depend on the type of penalty that is used. The prices also reflect service characteristics, including the technology provided, the download speed, and telephone call allowances. Plans that bundle mobile broadband plans with smartphone devices have longer contract duration and may be more expensive than plans that only include a SIM card. Specifically, broadband service plans are priced higher when they include an iPhone or a Samsung smartphone. The paper also discusses the impact of market structure and entry regulation on prices

Broadband prices in the European Union : competition and commercial strategies

This paper analyses the determinants of broadband Internet access prices in a group of 15 EU countries between 2008 and 2011. Using a rich panel dataset of broadband plans, we show the positive effect of downstream speed on prices, and report that cable and fibre-to-the-home technologies are available at lower prices per Mbps than x DSL technology. Operators’marketing strategies are also analysed as we show how much prices rise when the broadband service is offered in a bundle with voice telephony and/or television, and how much they fall when download volume caps are included. The most insightful results of this study are provided by a group of metrics that represent the situation of competition and entry patterns in the broadband market. We show that consumer segmentation positively affects prices. On the other hand, broadband prices are higher in countries where entrants make greater use of bitstream access and lower when they use more intensively direct access -local loop unbundling-. However, we do not find a significant effect of inter-platform competition on prices

Competencia en el mercado de banda ancha móvil en España

En los últimos años el servicio de banda ancha móvil ha tenido una fuerte expansión en España, hasta alcanzar una penetración de más del 70 por 100 de la población a principios de 2014. Este crecimiento puede explicarse por las prestaciones que ofrecen las tecnologías de tercera y cuarta generación en los terminales móviles actuales, y por las continuas reducciones de precios del servicio. A pesar de ello, los precios en España son todavía más altos que la media europea. Este artículo explica el proceso de innovación tecnológica que ha permitido el surgimiento de la banda ancha móvil, y su lanzamiento en España. Se examinan las nuevas estrategias comerciales que utilizan los operadores, como el empaquetamiento de servicios y los planes convergentes que incluyen servicios fijos y móviles. Nuestro análisis destaca que la presencia de los operadores móviles virtuales y el empaquetamiento han favorecido la competencia y la disminución de precios. También mostramos cómo la convergencia tecnológica entre los servicios fijos y móviles promueve la restructuración y concentración del mercado

El aprendizaje simbólico del cuerpo

El propósito de este artículo es analizar las relaciones entre el cuerpo y la educación como frente de sentido, y no solo en cuanto a su pura materialidad fisica. Tras un análisis previo de la "simbólica del cuerpo" y de la crisis de las sociedades modernas como una crisis de narración y de sentido (W. Benjamin), el artículo analiza críticamente el tratamiento que, de acuerdo con los estudios realizados por M. Foucault, la modernidad biopolitica ha impuesto al discurso sobre el cuerpo.The purpose of this article in to analysc relationship between body and education as a source of sense. After an previous analysis of symbolic dimension of body and de crisis of modern societies as a crisis of narrative and sense (W. Benjamin), the paper critically explore, in accord to M. Foucault, the modem biopolitical treatment of the body

El aprendizaje simbólico del cuerpo.

Sin resume

New speakers of minority languages: the challenging opportunity - foreword

In this special issue we examine and reflect upon the emergence of “new speakers” in the context of some of Europe’s minority languages. The “new speaker” label is used here to describe individuals with little or no home or community exposure to a minority language but who instead acquire it through immersion or bilingual educational programs, revitalization projects or as adult language learners. The emergence of this profile of speaker draws our attention to the ways in which minority linguistic communities are changing because of globalization and the new profiles of speakers that this new social order is creating. The concept also focuses our attention on some of the fundamental principles which had for a long time been taken for granted in much sociolinguistic research and in particular, language planning associated with linguistic revitalization. The authors of the eight articles included in this volume engage with these issues through their analyses of new speaker communities across a variety of European contexts including the Basque Country, Brittany, Catalonia, Corsica, Galicia, Ireland, the Isle of Man and Occitania