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Analysis of the influence of forest environments on the accuracy of GPS measurements by using genetic algorithms
Get PDF[EN] The present paper analyzes the influence of the forest canopy on the accuracy of the measurements performed by global positioning systems (GPS) receivers. The accuracy of a large set of observations is analyzed in the present research. These observations were taken with a GPS receiver at intervals of one second during a total time of an hour in twelve different points placed in forest areas characterized by a set of forest stand variables (tree density, volume of wood, Hart-Becking index, etc.). The influence on the accuracy of the measurements of other variables related to the GPS signal, such as the Position Dilution of Precision (PDOP), the signal-to-noise ratio and the number of satellites, was also studied. The analysis of the influence of the different variables on the accuracy of the measurements was performed by using genetic algorithms. The results obtained show that the variables with the highest influence on the accuracy of the GPS measurements are those related to the forest canopy, that is, the forest stand variables. The influence of these variables is almost equally important without significant statistical differences. As was expected, those observations recorded in areas covered by an important forest canopy have larger errors than those obtained in areas with less canopy cover. Finally, conclusions of this study are exposed.S
El derecho de acceso universal a internet en el marco normativo español: presente y futuro
No full text[ES] En los últimos años se ha incrementado el interés por el derecho de acceso a debido a su incidencia en el estatus de ciudadanía, en tanto que afecta a la igualdad de las personas, al ejercicio de otros derechos fundamentales, resulta indispensable para ejercer otros derechos, máxime con la pandemia de la Covid-19 que ha supuesto una acelerada digitalización: el teletrabajo, la asistencia sanitaria, la educación, las comunicaciones con las distintas administraciones, etc. se realizan a través de la Red. Es por ello que el presente artículo trata de analizar el derecho de acceso a internet en el vigente marco normativo español, para llegar a las propuestas normativas que pasan por el anteproyecto de la Ley General de Telecomunicaciones y la Carta de Derechos Digitales. De esta forma, trataremos de señalar aquellas cuestiones más relevantes al derecho que nos ocupa y de sugerir algunos cambios o mejoras en la normativa en aras a defender un verdadero derecho de acceso a internet dotado de las necesarias garantías.[EN] The right of access to the Internet has increased its interest due to its impact on citizenship status: it affects the equality of people, the exercise of other fundamental rights, it is essential to exercise other rights, etc. especially with the Covid-19 pandemic that has led to rapid digitization: teleworking, healthcare, education, communications with the different administrations, etc., they are carried out through the Internet. This paper analyze the right of access to the Internet in the current Spanish regulatory framework, to conclude with the regulatory proposals: the preliminary draft of the General Telecommunications Law and the Charter of Digital Rights.S
La abstracción de la palabra poética, voz silente de la catástrofe
No full text[ES] La poesía celaniana plantea fundamentalmente tres problemas imbricados:
la cuestión de la datación, implicando el estatuto ontológico del
poema –que Celan resolverá en su texto El Meridiano-; la superación de la
palabra esencial mallarmeana, al margen del espacio afectado por el discurso;
y el silencio devenido como palabra que perpetúa un testimonio frente
a la catástrofe. Un testimonio discontinuo que irrumpe en el encuentro del
lector y el poema
Reforma y tradición en el románico gallego: los ejemplos de Rebordáns y Mondoñedo
No full text419 p.[ES] El presente libro tiene como objetivo profundizar en el conocimiento
de la realidad artística del territorio gallego durante el último tercio del
siglo XI. Esta franja cronológica en el noroeste peninsular se caracteriza
por toda una serie de acontecimientos políticos, religiosos, territoriales y
culturales, que modificaron decisivamente las viejas estructuras hereda-
das del periodo altomedieval. En este contexto de cambio se ensayan una
serie de empresas artísticas que vinieron a establecer un nuevo paisaje
monumental, fundamentado en los criterios edilicios y decorativos dados
en llamar como románicos. La aparición de este nuevo lenguaje artístico
en un momento caracterizado por las reformas políticas y eclesiásticas es
una dinámica común a gran parte del territorio europeo occidental, lo que
ha motivado el establecimiento de toda una corriente historiográfica que
defiende que el nacimiento del arte románico es una consecuencia directa
de dichos procesos renovadores. Desde estas premisas, se tratará de com-
probar si este binomio arte/reforma es aplicable al caso gallego, centrándo-
nos especialmente en dos ejemplos concretos, no siempre suficientemente
ponderados a la hora de definir las dinámicas de creación del arte románico
en este territorio: las iglesias de San Martiño de Mondoñedo en Foz y San
Bartolomé de Rebordáns en Tui
Diachronic reconstruction of lost cultural heritage sites. Study case of the medieval wall of Ávila (Spain)
Get PDF[EN] The integration of the fourth dimension into the geospatial data allows to generate a diachronic model of Cultural Heritage (CH) assets, namely, a set of 3D models to represent it in various historical phases. This kind of reconstruction pursues a better understanding of the CH site/scenario, enriching the historical hypotheses as well as contributing to the conservation and decision-making process. Although the new geotechnologies have reduced the amount of fieldwork, the generation of 4D model implies the interpretation of heterogeneous historical information sources and their integration. However, this situation could reach a critical point when the study elements are no longer present. Their reconstruction will allow the digital preservation and maintenance of our culture. The main challenge is to harmonize the different historical and archaeological data sources available in relation with the current remains, to recover the lost CH assets with a high degree of reliability. This manuscript aims to examine the study case of a diachronic reconstruction by means of the use of the geotechnology Mobile Laser System (MLS) and reverse engineering techniques for a lost urban CH element, the citadel or Alcázar Gate of Ávila. Within this aim, the derived product is evaluated in terms of the achieved accuracy to assess its suitability on the basis of constructive interpretations required to integrate the historical sources in relation to current remains and the surroundingSIThe authors wish to express our gratitude for the support of the European Union through the Joint Programming Initiative on Cultural Heritage (JPI-CH), for funding the project Cultural Heritage Through Time (CHT2), as well as to the Ministry of Economy and Competitiveness of Spai
Multilingual textual data: an approach through multiple factor analysis
Get PDF[EN] This paper focuses on the analysis of open-ended questions answered in different
languages. Closed-ended questions, called contextual variables, are asked to all
respondents in order to understand the relationships between open-ended and closedended
responses across samples, as the latter are likely to influence word choice. We have
developed "Multiple Factor Analysis on Generalised Aggregated Lexical Tables" (MFAGALT)
to examine together open-ended responses in different languages through the relationships
between word choice and the variables that drive that choice. MFA-GALT
investigates whether the variability between words is structured in the same way as the
variability between variables, and vice versa, from one sample to another. An application
to an international satisfaction survey shows the easy-to-interpret results proposed.S
Derecho e interculturalidad
No full text[ES] La interculturalidad puede definirse como la “presencia e interacción equitativa de diversas culturas y la posibilidad de generar expresiones culturales compartidas, adquiridas por medio del diálogo y de una actitud de respeto mutuo” (art. 4.8, CPPDEC, 2005). Así, las expresiones culturales compartidas serían el resultado de la interculturalidad; la presencia e interacción equitativa de las diversas culturas sus condiciones; y, el diálogo y la actitud de respeto mutuo las vías que conducen a dicho logro. Garantizar las condiciones y las vías que hacen posible la interculturalidad, exige respuestas por parte del derecho, tales como: el reconocimiento de derechos culturales, la educación inclusiva en y desde la diversidad, la afirmación del derecho a la diferencia, las garantías jurídicas de la existencia de pluralismo étnico, cultural y religioso, el reconocimiento de las minorías étnicas, culturales y religiosas, la apertura de cauces de participación, el derecho a la identidad personal y cultural, el derecho a la libertad de conciencia
4D reconstruction of cultural heritage sites
Get PDF[EN] Multi-temporal three-dimensional (3D) reconstructions arefundamental for the preservation and maintenance of all forms of tangibleCultural Heritage (CH) and often provide the basis for decisions related tointerventions and promotion. Introducing the fourth dimension of time into 3Dgeometric modelling of real-world data allows the creation of a multi-temporalrepresentation of a site to plan maintenance and promotion. This chapter aims toprovide a comprehensive approach for CH time-varying representations, tointegrate heterogeneous information derived from a range of sources to helpinform understanding of temporal aspects of change across different workingscales and environments. Two landscape-scale study cases, Hadrian’s Wall (UK)and Milan Roman Circus (Italy), are presented based on a methodologicalapproach for CH time-varying representations proposed by the JPI-CH EuropeanProject Cultural Heritage Through Time (CHT2). CHT2 aims to provide a new setof tools and working methods to support the study of the evolution of CH sitesThe authors wish to acknowledge the support of the European Union’s Joint Programming Initiative on Cultural Heritage (JPI-CH), for funding the project Cultural Heritage Through Time (CHT 2), through national research authorities: UK Arts and Humanities Research Council (AHRC, award number AH/N504440/1), Spanish Ministry of Economy and Competitiveness, and Polish Ministry of Culture and National Heritag
Development of an all-purpose free photogrammetric tool
Get PDF[EN] Photogrammetry is currently facing some challenges and changes mainly related to automation, ubiquitous processing and variety of applications. Within an ISPRS Scientific Initiative a team of researchers from USAL, UCLM, FBK and UNIBO have developed an open photogrammetric tool, called GRAPHOS (inteGRAted PHOtogrammetric Suite). GRAPHOS allows to obtain dense and metric 3D point clouds from terrestrial and UAV images. It encloses robust photogrammetric and computer vision algorithms with the following aims: (i) increase automation, allowing to get dense 3D point clouds through a friendly and easy-to-use interface; (ii) increase flexibility, working with any type of images, scenarios and cameras; (iii) improve quality, guaranteeing high accuracy and resolution; (iv) preserve photogrammetric reliability and repeatability. Last but not least, GRAPHOS has also an educational component reinforced with some didactical explanations about algorithms and their performance. The developments were carried out at different levels: GUI realization, image pre-processing, photogrammetric processing with weight parameters, dataset creation and system evaluation. The paper will present in detail the developments of GRAPHOS with all its photogrammetric components and the evaluation analyses based on various image datasets. GRAPHOS is distributed for free for research and educational needsS
Developing customized fuel models for shrub and bracken communities in Galicia (NW Spain)
Get PDF[EN] Geospatial fire behaviour and fire hazard simulators, fire effects models and smoke emission software commonly use standard fuel models in order to simplify data collection and the inclusion of complex fuel scenarios. These fuel models are often mapped using remotely sensed data. However, given the great complexity of fuelbeds, with properties that vary widely in both time and space, the use of these standard fuel models can greatly limit accurate fuel mapping. This affects fuel hazard assessment, fuel reduction treatment plans, fire management decision-making and evaluation of the environmental impact of wildfire. In this study, we developed unique customized fire behaviour fuel models for shrub and bracken communities, by using k-medoids clustering analysis based on both fuel structural characteristics and potential fire behaviour. We used an original database of 722 destructive sample plots in nine different shrub and bracken communities covering the entire distribution area in Galicia (NW Spain), one of the regions in Europe most affected by forest fires. Measurements of cover, height and fuel fractions loads differentiated by size and vegetative state (live or dead) were used to estimate the potential rate of fire spread with five different models including fireline intensity, heat per unit area and the flame length for each sampling site and considering extreme environmental conditions. The optimal number of clusters was established by combining practical knowledge about the shrubland communities under study and their associated fire behaviour, with maximization of the mean value of the silhouette variable and minimization of the within-cluster sum of squares. The structural characteristics of the medoids derived from the analysis were associated with each of the proposed customized fuel models. Finally, a simple dichotomous classification based only on shrub height was developed to enable construction of spatially explicit fuel model maps based on remotely sensed data. Thus, the methodology applied allows generation of a more realistic representation of fuel distribution in the landscape, based on fuel structure measurements of natural regional ecosystems rather than on the use of standard models. We believe that the proposed methodology is generally applicable to communities composed of other shrub and fern species in different biogeographical regions.SISpanish National Program of Research, Development and Innovation (Plan Estatal de I + D + i) co-financed by the European Regional Development Fund (ERDF) of the European UnionEuropean CommissionEuropean Regional Development Fund (ERDF