131 research outputs found
Caracterización fitoecológica de los sabinares albares de la Península Ibérica
Tras el estudio de las comunidades de Juniperus thurifera L. en la Peninsula Ibérica mediante análisis multivariante de ordenación. (DECORANA) y de clasificación (TWINSPAN), se propone una caracterización de 10s sabinares albares. El tratamiento tipológico propuesto por nosotros distingue cuatro modalidades de sabinares: cantábricos, de paramera, termófilos y acidófilos.Communities of Juniperus thurifera L. in the Iberian Peninsula were studied using multivariate analysis of ordination (DECORANA) and classification (TWINSPAN). The typological treatment we propose as a result of these studies distinguishes four types of J. thurifera communities: cantabrian, paramo, thermophilic and acidophilic
Aproximación a la bibliografía florística básica de la Peninsula Ibérica e Islas Baleares.
MORENO SAuz, J. C. & SAINZ OLLERO, H. 1989. An aproxirnation to the floristic basic bibliography of the Iberian Peninsula and Balearic Islands. BoL ComplutenSis 15: 175-202. A compilation of floristic catalogues from Iberian Península and Balearic Lslands is presented. Tbese works have been sorted out by countries and provinces. A geografical representation of their distribution has been drown in a map.MORENO SÁIZ, £ C. & SAINZ OLLERO, H. 1989. Aproximación a la bibliografía floristica básica de la Península Ibérica e Islas Baleares. Bot Comp/utensis 15: 175202 Se lleva a cabo una recopilación de catálogos floristicos elaborados dentro del territorio de la Península Ibérica e Islas Baleares.Dichos trabajos se han ordenado por países y provincias y representado geográficamente en un mapa de distribucion
Classification and mapping of Spanish Mediterranean mixed forests
Mixed forests play an important role in promoting forest functions and services, and showed better resilience to perturbations than monospecific forests. In the Mediterranean Basin they constitute an important share of the total forest area. However, although mixed forests have been described, classified and mapped in most of the Mediterranean regions around the world, in the Mediterranean Basin they remain neglected, with direct negative consequences for forest management and conservation strategies. Our objective is to present a reliable, uniform classification along with a map of the Spanish Mediterranean Mixed Forests (MMF) as a tool for their management and conservation in Spain. The digital Spanish Forest Map was analyzed to identify MMF. The most frequent tree species combinations were identified and their representativeness in terms of the total forest area was analyzed. In addition, to ensure environmental homogeneity in the proposed classification, the arrangement of each tree species combination within the Spanish Mediterranean ecoregions was evaluated using the Pearson Chi-square test. Based on our results, Spanish MMF currently cover 27.07% of the Mediterranean natural forest area. They were divided into 9 main ecological groups and 23 subtypes. The classification of Spanish MMF and the distribution map represent a first step towards recognizing the importance of mixed forests in the vegetation of the Mediterranean Basin. Together they may provide a valuable basis to improve future forest management, monitoring and conservation strategies both at national and European level
Aerial video geo-registration using terrain models from dense and coherent stereo matching
In the context of aerial imagery, one of the first steps toward a coherent processing of the information contained
in multiple images is geo-registration, which consists in assigning geographic 3D coordinates to the pixels of the
image. This enables accurate alignment and geo-positioning of multiple images, detection of moving objects
and fusion of data acquired from multiple sensors.
To solve this problem there are different approaches that
require, in addition to a precise characterization of the camera sensor, high resolution referenced images or terrain
elevation models, which are usually not publicly available or out of date. Building upon the idea of developing
technology that does not need a reference terrain elevation model, we propose a geo-registration technique that
applies variational methods to obtain a dense and coherent surface elevation model that is used to replace the
reference model. The surface elevation model is built by interpolation of scattered 3D points, which are obtained
in a two-step process following a classical stereo pipeline: first, coherent disparity maps between image pairs
of a video sequence are estimated and then image point correspondences are back-projected.
The proposed variational method enforces continuity of the disparity map not only along epipolar lines (as done by previous geo-registration techniques) but also across them, in the full 2D image domain. In the experiments, aerial images from synthetic video sequences have been used to validate the proposed technique
Robust Image Registration with Global Intensity Transformation
This paper presents a registration method for images with global illumination variations. The method is based on a joint iterative optimization (geometric and photometric) of the L1 norm of the intensity error. Two strategies are compared to directly find the appropriate intensity transformation within each iteration: histogram specification and the solution obtained by analyzing the necessary optimality conditions. Such strategies reduce the search space of the joint optimization to that of the geometric transformation between the images
Huellas terópodas gigantes en el Jurásico Superior de Marruecos. Yacimiento de Aït Mazight (Atlas Central)
A new small site, not always outcropping, with large and giant theropod tracks in the Upper Jurassic of the Central High Atlas of Morocco is described. The ichnites and the typology of the rocks of the site are similar to those of the Iouaridène sites with which there is no cartographic continuity. The particular characters of the tracks and trackways are analyzed and highlighted and a hypothesis of distribution of this type of dinosaurs is pointed outSe describe un nuevo yacimiento pequeño, no siempre aflorante, con huellas terópodas grandes y gigantes en el Jurásico Superior del Alto Atlas Central de Marruecos. Las icnitas y la tipología de las rocas en las que yacen son similares a las de los yacimientos de Iouaridène con los que no hay continuidad cartográfica. Se analizan y destacan los caracteres particularesde las huellas y rastrilladas y se apunta una hipótesis de distribución de este tipo de dinosaurio
Methodology for the Optimal Design of a Hybrid Charging Station of Electric and Fuel Cell Vehicles Supplied by Renewable Energies and an Energy Storage System
The global energy system is changing, mainly to achieve sustainable transport technologies
and clean electrical generation based on renewable sources. Thus, as fuels, electricity and hydrogen
are the most promising transport technologies in order to reduce greenhouse emissions. On the other
hand, photovoltaic and wind energies, including energy storage, have become the main sources of
distributed generation. This study proposes a new optimal-technical sizing method based on the
Simulink Design Optimization of a stand-alone microgrid with renewable energy sources and energy
storage to provide energy to a wireless power transfer system to charge electric vehicles along a
motorway and to a hydrogen charging station for fuel cell-powered buses. The results show that
the design system can provide energy for the charging of electric vehicles along the motorway and
produce the hydrogen consumed by the fuel cell-buses plus a certain tank reserve. The flexibility
of the study allows the analysis of other scenarios, design requirements, configurations or types
of microgrids
First record of Ochthebius (Ochthebius judemaesi Delgado & Jäch, 2007 in Nothern Africa (Coleoptera: Hydraenidae)
The group Ochthebius (Ochthebius) metallescens, proposed by ORCHYMONT (1942), currently includes more than 50 species found in small headwaters in the occidental Paleartic region
Estudio macro y mesoestructural en la cubeta de Morés (Cordillera Ibérica)
Estudio estructural de la cubeta de Morés a distintas escalas con el objetivo de determinar los esfuerzos a los que ha sido sometida la zona de estudio y presentar una propuesta de evolución tectónica a partir de los datos obtenidos a pie de campo.<br /
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