Can low-cost road vehicles positioning systems fulfil accuracy specifications of new ADAS applications?

Some new Advanced Driver Assistance Sy stems (ADAS) need on-the-lane vehicle positioning on accurate digital maps, but present applications of vehicle positioning do not justify the surcharge of very ac curate equipment such as DGPS or high-cost inertial systems. For this reason, performance of GPS in autonomous mode is analyzed. Although satisfactory results can be found, in some areas GPS signal is lost or degraded, so it is necessary to know the positioning error when using only inertial system data. A th eoretical approach based on the uncertainty propagation law is used to esti mate the upper limit of distance that can be travelled fulfilling the specifications of an assistance system. Tests results support the conclusions of this approach. Finally, the comb ination of GPS and inertial systems is studied, resulting that the theoretical approach is valid when inertial measurements are used right from the start of GPS signal de gradation, without waiting for a complete loss.The work reported in this paper has been partly funded by the Spanish Ministry of Science and Innovation (SIAC project TRA2007-67786-C02-01 and TRA2007-67786-C02-02) and the CAM project SEGVAUTO.Publicad

A single dose of beetroot juice not enhance performance during intervallic swimming efforts

Despite the numerous scientific evidence on the topic, there is no clear and consistent answer that clarifies the true effects of beet- root juice (BJ) supplementation on different types of physical per- formance. This study examined whether an acute intake of BJ im- proves swimming performance, physiological variables of anaer- obic metabolism, or subjective measures during high-intensity in- terval exercise with incomplete rest in competitive swimmers. Eighteen competitive swimmers (nine females and nine males) participated in this cross-over randomized, placebo-controlled, double-blind and counterbalanced study. In two trials, swimmers ingested BJ (70 mL, 6.4 mmol/400 mg NO3-) or placebo (PLA) (70 mL, 0.04 mmol/3 mg NO3-) three hours before a 2×6×100 m maximal effort with 40 seconds rest between repetitions and three minutes between blocks. The 100 m times showed no differences between groups (p > 0.05), but there was an interaction between block×repetition×condition (F5 = 3.10; p = 0.046; ηp2 = 0.54), in- dicating that the BJ group decreased the time of the sixth repeti- tion of block2 compared to block1 (p = 0.01). Lactate concentra- tion showed no differences between conditions (p > 0.05), but there was a main effect of block (ηp2 = 0.60) and a block×repeti- tion interaction (ηp2 = 0.70), indicating higher values in block2 and increasing values between repetitions in block1. The subjec- tive scales, perception of exertion (RPE) and Total Quality Re- covery (TQR), showed no effects of condition (p > 0.05), but BJ swimmers had a greater TQR in the last repetitions of each block. In conclusion, a single dose of BJ did not enhance intermittent swimming performance or modified the physiological (lactate and heart rate) or subjective (RPE and TQR) variables; although there was a possible positive effect on the exercise tolerance at the end of effort.We thank the swimmers and coaches who participated in the experiment for their valuable input on the details of the study. We also thank all the researchers who assisted in the data collection process, in particular MMP and ACS for their unconditional support. The other authors declare no potential or actual conflicts of interest. The datasets generated and ana- lyzed during the current study are not publicly available, but are available from the corresponding author who was an organizer of the study. The experiments comply with the current laws of the country where they were performed.info:eu-repo/semantics/publishedVersio

Specification and Development of a HMI for ADAS, Based in Usability and Accessibility Principles

Traditionally, the design of road vehicle HMI is based in esthetic principles, maintaining it as an attractive factor for possible clients when buying a car. Only recently, ergonomic benefits have been applied to the design of HMIs, mainly following institutional impulses like the European Union one, but whose contribution is not clearly stated nowadays in commercial products. In this paper the authors present a study of the design of an HMI, based in usability and accessibility premises, centering the design in the user, as method to improve safety, making natural the communication with the driver as well as being able to transmitting information to the driver, from basic to the generated by ADAS installed in the car. Following these specifications a set of prototypes have been designed in order to develop a testbed that could be evaluated for a large set of drivers.This work has been supported by the Spanish Ministry of Science and Innovation (TRA2007-67786 and TRA2009-07505) and the CAM project SEGVAUTO-II.Publicad

Fingerprint ridge density in the Argentinean population and its application to sex inference: A comparative study

Fingerprint ridge density (RD) is known to vary according to sex and population, and such variation can be used for forensic purposes. The aim of this study was to analyze the fingerprint RD of two samples of the Argentinean population in order to assess their topological, digital, bilateral, sexual, and population differences for subsequent application in the inference of sex. Data were collected from the fingerprints of 172 individuals from the Buenos Aires province and 163 from the Chubut province. RD was assessed for three different count areas for all 10 fingers of each individual. In both sexes and both samples, significant differences among areas were obtained, so that radial-RD > ulnar-RD > proximal-RD. Females presented greater RD than males in all areas and on all fingers. Regarding population differences, no significant differences were found between the Buenos Aires and Chubut samples (except for proximal RD in males). However, both samples showed RD significantly different from that of the Jujuy province. The application of Bayes? theorem allowed for the identification of an RD threshold for discrimination of sexes in these Argentinean samples. In conclusion females consistently exhibit narrower epidermal ridges than males, which may evidence a universal pattern of sexual dimorphism in this trait that can be useful in forensics in the identification of individuals.Agencia Española de Cooperación Internacional para el Desarroll

Academic competence, teacher–student relationship, and violence and victimisation in adolescents: The classroom climate as a mediator

School violence is a serious social and public health problem prevalent worldwide. Alt-hough the relevance of teacher and classroom factors is well established in the literature, few studies have focused on the role of teacher perceptions in school violence and victimisation and the poten-tial mediational role of classroom climate in this relationship. A total of 2399 adolescents (50% girls), aged between 11 and 18 years (M = 14.65, SD = 1.78) and enrolled in five Spanish Secondary Com-pulsory Education schools completed measures of classroom climate, school violence towards peers and perception of peer victimisation, and their teachers informed about their academic competence and the teacher–student relationship. Correlational analyses revealed that whereas academic competence perceived by the teacher was negatively related to overt violence and victimisation, its relationship with pure relational violence was positive. Structural equation modelling analyses showed that variables of classroom climate (involvement, affiliation, and teacher support) perceived by the students functioned as partial mediators between teacher perceptions of academic competence and of teacher–student relationship and violence and victimisation. In the mediational model, teacher perception of academic competence acted as a direct protective factor against violence and victimisation, and teacher perception of teacher–student relationship acted as a direct risk for violence, as well as an indirect protective factor through classroom climate for victimisation. The interpretation of these results points to the importance of the teacher’s subjective perceptions in the prevention of violence and victimisation problems and their practical implications for the classroom climate perceived by students

RELACIÓN ENTRE MATERIALES GEOLÓGICOS Y LAS PROPIEDADES FÍSICAS Y QUÍMICAS DE LOS SUELOS.

El presente estudio fue realizado en la zona de influencia de la cordillera del Ybytyruzu en el Departamento de Guaira, localidad ubicada al sureste de Asunción. El objetivo principal de la presente investigación fue identificar los principales efectos que producen la roca basáltica y la roca arenisca sobre las propiedades físicas y químicas de los suelos formados a partir de ellas. La metodología aplicada en este estudio consistió en trabajos de campo y análisis laboratorial de las muestras obtenidas.Los resultados indican marcada diferencia, tanto en las propiedades físicas y químicas, entre los suelos originados de rocas sedimentarias - arenisca y suelos originados de rocas ígneas - basalto. La textura gruesa es dominante para suelos originados de arenisca, mientras que la textura fina predomina en suelos originados de basalto. Utilizando el método del tacto también se identificó importantes diferencias en la plasticidad y pegajosidad de suelos originados de rocas sedimentarias – areniscas fue muy baja en relación a suelos originados de roca basáltica. La estructuración también fue más débil en suelos de textura gruesa en comparación a suelos de textura fina. En cuanto al tamaño de poros se puede mencionar que los suelos de textura gruesa, conpredominancia de arena presentan mayor cantidad de macroporos en comparación a suelos de textura fina en donde se observó mayor cantidad de microporos.En relación a los aspectos químicos, el pH en suelos originados de rocas sedimentarias presenta menor rango en relación a los suelos originados de basalto. En cuanto a la acidez intercambiable, el nivel fue mayor en suelos originados de roca sedimentaria que los suelos de textura fina. Las sumas de bases, el contenido de materia orgánica y el nivel de fósforo sin embargo presentaron rangos menores para suelos de textura gruesa en relación a los suelos de textura fina

Environment perception based on LIDAR sensors for real road applications

The recent developments in applications that have been designed to increase road safety require reliable and trustworthy sensors. Keeping this in mind, the most up-to-date research in the field of automotive technologies has shown that LIDARs are a very reliable sensor family. In this paper, a new approach to road obstacle classification is proposed and tested. Two different LIDAR sensors are compared by focusing on their main characteristics with respect to road applications. The viability of these sensors in real applications has been tested, where the results of this analysis are presented.The recent developments in applications that have been designed to increase road safety require reliable and trustworthy sensors. Keeping this in mind, the most up-to-date research in the field of automotive technologies has shown that LIDARs are a very reliable sensor family. In this paper, a new approach to road obstacle classification is proposed and tested. Two different LIDAR sensors are compared by focusing on their main characteristics with respect to road applications. The viability of these sensors in real applications has been tested, where the results of this analysis are presented.The work reported in this paper has been partly funded by the Spanish Ministry of Science and Innovation (TRA2007- 67786-C02-01, TRA2007-67786-C02-02, and TRA2009- 07505) and the CAM project SEGVAUTO-II.Publicad

Limitations of positioning systems for developing digital maps and locating vehicles according to the specifications of future driver assistance systems

Some advanced driver assistance systems require on-the-lane vehicle positioning on accurate digital maps. The combination of high precision global navigation satellite systems and inertial measurement is the most common technique to carry out this precise positioning since in some areas global positioning systems (GPS) signals are lost or degraded. However, real experimental validation of the navigation algorithms (beyond simulation) is one of the most important shortcomings in the state-of-the-art. In this study, a wide set of real experiments have been carried out on real roads, in urban and rural environments, using an instrumented car. A theoretical approach based on the uncertainty propagation law has been set out to evaluate the errors when using only inertial measurement systems and the maximum distance that can be travelled before exceeding the admissible error limits. Results show that it is better to correct GPS positioning when its signal is degraded than to wait until the signal is definitively lost. Furthermore, inertial measurement systems and GPS receivers of different levels of accuracy have been compared in order to determine whether they are suitable for new assistance applications. Experimental data are consistent with the theoretical approach.The work reported in this paper has been partly funded by the Spanish Ministry of Science and Innovation (SIAC project TRA2007-67786-C02-01 and TRA2007-67786-C02-02) and the CAM project SEGVAUTO.Publicad

Investigaciones Sobre Programación del Riego en Limonero y Olivo Mediante Medidas Directas y Continuas del Estado Hídrico.

En el presente trabajo se realiza una revisión del estado actual de conocimientos sobre aspectos relativos a la utilización de medidas continuas del estado hídrico del limonero y olivo para su utilización en la programación del riego, abarcando, esencialmente, aspectos tales como la sensibilidad de distintos indicadores del estado hídrico medidos de forma continua o discontinua en las plantas, su significado fisiológico, la obtención de niveles de referencia de los indicadores y primeros resultados sobre programación del riegoThe feasibility of irrigation scheduling in olive and lemon trees using continuously recorded plant-based water stress indicators was studied. For this, the characteristics of different plant-based water stress indicators (stem water potential, sap flow and trunk diameter fluctuations), their sensibility and limitations for water stress diagnosis purposes was discussed. The ways in which data can be interpreted, and protocols for irrigation scheduling was also described