The twenty first century: «globalisation» and «regionalisation»*

En los inicios del siglo XXI podemos afirmar, sin temor a equivocarnos, que uno los elementos definidos por la globalización aumentan del mismo modo que el desarrollo tecnológico arrollador y desenfrenado, cuyos efectos empezamos a constatar. Una de las causas de ello es que la desigualdad, como consecuencia de ese desarrollo tecnológico, va haciéndose hueco en nuestra sociedad. Todo ello atañe de igual modo al medio ambiente (tanto la conservación como la mejora). Por ello, el desarrollo debe ser entendido desde una perspectiva más amplia incluyendo los recursos naturales y renovables, el origen de la contaminación atmosférica, ruidos, conservación de los ecosistemas y las especies autóctonas. En pocas palabras, el desarrollo es lo que enmarca a la sociedad en su conjunto (instituciones, cultura, naturaleza, ciudades, hábitat, economía, tecnología,...), más todas las cuestiones relacionadas con la vida humana.En los inicios del siglo XXI podemos afirmar, sin temor a equivocarnos, que uno los elementos definidos por la globalización aumentan del mismo modo que el desarrollo tecnológico arrollador y desenfrenado, cuyos efectos empezamos a constatar. Una de las causas de ello es que la desigualdad, como consecuencia de ese desarrollo tecnológico, va haciéndose hueco en nuestra sociedad. Todo ello atañe de igual modo al medio ambiente (tanto la conservación como la mejora). Por ello, el desarrollo debe ser entendido desde una perspectiva más amplia incluyendo los recursos naturales y renovables, el origen de la contaminación atmosférica, ruidos, conservación de los ecosistemas y las especies autóctonas. En pocas palabras, el desarrollo es lo que enmarca a la sociedad en su conjunto (instituciones, cultura, naturaleza, ciudades, hábitat, economía, tecnología,...), más todas las cuestiones relacionadas con la vida humana

La degradación medioambiental de la cuenca mediterránea: conservación vs. gestión de unos recursos y de un patrimonio compartido

El clima mediterráneo, unido a la complejidad del territorio y la historia de los usos del suelo, nos permite considerar los distintos tipos de paisajes como respuesta a las condiciones de un medio fluctuante, en ocasiones marcadamente impredecible. Se propone la necesidad incluir los agroecosistemas y paisajes valiosos en los planteamientos territoriales de conservación de la naturaleza. En las últimas décadas, el Mediterráneo ha sido objeto de una significativa transformación socioeconómica; lo cual ha diferenciado cambios demográficos, cambios en los usos del suelo y, en consecuencia, cambios en los usos y demanda de agua. Esta transformación ha generado unidades ambientales de referencia (interior, intermedia y litoral); el actual modelo de desarrollo es ecológicamente insostenible.The Mediterranean climate, the land complexity and the history of land uses, allows us to consider the different landscapes as an adaptation to a fluctuating environment, which is in many instances markedly unpredictable. We emphasize the need to include agroecosystems and valuable landscapes in land management schemes derived from the application of conservation policies. In the last decades the Mediterranean region has been subjected to significant socioeconomic transformations; which has generated demographic changes, land use changes, and ensuing changes in water uses and demand. Recent transformations have gradually differentiated environmental units of reference (interior, intermediate and coastal); the current development model is ecologically unsustainable

Vision-Based Traffic Data Collection Sensor for Automotive Applications

This paper presents a complete vision sensor onboard a moving vehicle which collects the traffic data in its local area in daytime conditions. The sensor comprises a rear looking and a forward looking camera. Thus, a representative description of the traffic conditions in the local area of the host vehicle can be computed. The proposed sensor detects the number of vehicles (traffic load), their relative positions and their relative velocities in a four-stage process: lane detection, candidates selection, vehicles classification and tracking. Absolute velocities (average road speed) and global positioning are obtained after combining the outputs provided by the vision sensor with the data supplied by the CAN Bus and a GPS sensor. The presented experiments are promising in terms of detection performance and accuracy in order to be validated for applications in the context of the automotive industry

Exploring the high-temperature electrical performance of Ca3-xLaxCo4O9 thermoelectric ceramics for moderate and low substitution levels

Aliovalent substitutions in Ca3Co4O9 often result in complex effects on the electrical prop-erties and the solubility, and impact of the substituting cation also depends largely on the prepara-tion and processing method. It is also well-known that the monoclinic symmetry of this material’s composite crystal structure allows for a significant hole transfer from the rock salt-type Ca2CoO3 buffer layers to the hexagonal CoO2 ones, increasing the concentration of holes and breaking the electron–hole symmetry from the latter layers. This work explored the relevant effects of relatively low La-for-Ca substitutions, for samples prepared and processed through a conventional ceramic route, chosen for its simplicity. The obtained results show that the actual substitution level does not exceed 0.03 (x < 0.03) in Ca3-xLaxCo4O9 samples with x = 0.01, 0.03, 0.05 and 0.07 and that further introduction of lanthanum results in simultaneous Ca3Co4O9 phase decomposition and secondary Ca3Co2O6 and (La,Ca)CoO3 phase formation. The microstructural effects promoted by this phase evolution have a moderate influence on the electronic transport. The electrical measurements and determined average oxidation state of cobalt at room temperature suggest that the present La sub-stitutions might only have a minor effect on the concentration of charge carriers and/or their mobil-ity. The electrical resistivity values of the Ca3-xLaxCo4O9 samples with x = 0.01, 0.03 and 0.05 were found to be ~1.3 times (or 24%) lower (considering mean values) than those measured for the pris-tine Ca3Co4O9 samples, while the changes in Seebeck coefficient values were only moderate. The highest power factor value calculated for Ca2.99La0.01Co4O9 (~0.28 mW/K2m at 800 °C) is among the best found in the literature for similar materials. The obtained results suggest that low rare-earth substitutions in the rock salt-type layers can be a promising pathway in designing and improving these p-type thermoelectric oxides, provided by the strong interplay between the mobility of charge carriers and their concentration, capable of breaking the electron–hole symmetry from the conduc-tive layers.publishe

Estudio tecnológico sobre la prevención y mecanismos de extinción de incendios

El objetivo de dicho proyecto ha sido hacer un balance general y dar a conocer los aspectos más significativos sobre un tema que cada día está más presente en la vida cotidiana de las personas como es la prevención de incendios. El proyecto también ha tratado de englobar aspectos relacionados con el desarrollo y extinción de los incendios en diferentes ámbitos y condicione

Estudio de nuevos materiales termoeléctricos basados en óxidos cerámicos

Determinar cómo varían las propiedades termoeléctricas del material 349 puro (Ca3Co4O9) al doparlo, sustituyendo parte del cobalto por cromo y por cobre en cada caso. Las probetas se analizarán por el método de las cuatro puntas para comprobar los resultados

Diagnosis of Broken Rotor Bars during the Startup of Inverter-Fed Induction Motors Using the Dragon Transform and Functional ANOVA

[EN] A proper diagnosis of the state of an induction motor is of great interest to industry given the great importance of the extended use of this motor. Presently, the use of this motor driven by a frequency converter is very widespread. However, operation by means of an inverter introduces certain difficulties for a correct diagnosis, which results in a signal with higher harmonic content and noise level, which makes it difficult to perform a correct diagnosis. To solve these problems, this article proposes the use of a time-frequency technique known as Dragon Transform together with the functional ANOVA statistical technique to carry out a proper diagnosis of the state of the motor by working directly with the curves obtained from the application of the transform. A case study is presented showing the good results obtained by applying the methodology in which the state of the rotor bars of an inverter-fed motor is diagnosed considering three failure states and operating at different load levels.This research has been partially funded by the University of Valladolid.Fernández-Cavero, V.; García-Escudero, LA.; Pons Llinares, J.; Fernández-Temprano, MA.; Duque-Perez, O.; Morinigo-Sotelo, D. (2021). Diagnosis of Broken Rotor Bars during the Startup of Inverter-Fed Induction Motors Using the Dragon Transform and Functional ANOVA. Applied Sciences. 11(9):1-12. https://doi.org/10.3390/app1109376911211

Laser transmission welding as an assembling process for high temperature electronic packaging.

Higher efficiency, power density, reliability and longer lifetime of power electronic devices would stem from progresses in material science. In this work, we propose to use a high performance thermoplastic polymer PAEK as packaging box to extend the operating temperature above 200°C. More, the laser transmission welding process has been applied to PAEK to join the two-part module. In order to validate this assembling process, the temperature distribution inside the specimens was measured during laser transmission welding. The assembly consists of a quasi-amorphous sample as the upper part and a semi-crystalline sample as the lower part. The temperature fields were measured by infrared thermography with the camera sensor perpendicular to the welded interface. With an energy beam of 28 J.mm-2 and irradiation time of 15 s, we have noticed that the maximum temperature inside the sample is kept far from the PAEK degradation one. Moreover, the temperature at the interface reaches the melting temperature thus assuring enough mobility for polymeric chains to get adhesion at the interface. The location and size of the heat-affected zone has been determined. Finally, some frames were machined and successfully welded

Autonomous navigation and obstacle avoidance of a micro-bus: Regular paper

At present, the topic of automated vehicles is one of the most promising research areas in the field of Intelligent Transportation Systems (ITS). The use of automated vehicles for public transportation also contributes to reductions in congestion levels and to improvements in traffic flow. Moreover, electrical public autonomous vehicles are environmentally friendly, provide better air quality and contribute to energy conservation. The driverless public transportation systems, which are at present operating in some airports and train stations, are restricted to dedicated roads and exhibit serious trouble dynamically avoiding obstacles in the trajectory. In this paper, an electric autonomous mini-bus is presented. All datasets used in this article were collected during the experiments carried out in the demonstration event of the 2012 IEEE Intelligent Vehicles Symposium that took place in Alcalá de Henares (Spain). The demonstration consisted of a route 725 metres long containing a list of latitude-longitude points (waypoints). The mini-bus was capable of driving autonomously from one waypoint to another using a GPS sensor. Furthermore, the vehicle is provided with a multi-beam Laser Imaging Detection and Ranging (LIDAR) sensor for surrounding reconstruction and obstacle detection. When an obstacle is detected in the planned path, the planned route is modified in order to avoid the obstacle and continue ist way to the end of the mission. On the demonstration day, a total of 196 attendees had the opportunity to get a ride on the vehicles. A total of 28 laps were successfully completed in full autonomous mode in a private circuit located in the National Institute for Aerospace Research (INTA), Spain. In other words, the system completed 20.3 km of driverless navigation and obstacle avoidance

Error Analysis in a Stereo Vision-Based Pedestrian Detection Sensor for Collision Avoidance Applications

This paper presents an analytical study of the depth estimation error of a stereo vision-based pedestrian detection sensor for automotive applications such as pedestrian collision avoidance and/or mitigation. The sensor comprises two synchronized and calibrated low-cost cameras. Pedestrians are detected by combining a 3D clustering method with Support Vector Machine-based (SVM) classification. The influence of the sensor parameters in the stereo quantization errors is analyzed in detail providing a point of reference for choosing the sensor setup according to the application requirements. The sensor is then validated in real experiments. Collision avoidance maneuvers by steering are carried out by manual driving. A real time kinematic differential global positioning system (RTK-DGPS) is used to provide ground truth data corresponding to both the pedestrian and the host vehicle locations. The performed field test provided encouraging results and proved the validity of the proposed sensor for being used in the automotive sector towards applications such as autonomous pedestrian collision avoidance