The Suitability of UAV-Derived DSMs and the Impact of DEM Resolutions on Rockfall Numerical Simulations: A Case Study of the Bouanane Active Scarp, Tétouan, Northern Morocco

Rockfall simulations constitute the first step toward hazard assessments and can guide future rockfall prevention efforts. In this work, we assess the impact of digital elevation model (DEM) resolution on the accuracy of numerical rockfall simulation outputs. For this purpose, we compared the simulation output obtained using 1 m, 2 m and 3 m resolution UAV-derived DEMs, to two other models based on coarser topographic data (a 5 m resolution DEM obtained through interpolating elevation contours and the Shuttle Radar Topographic Mission 30m DEM). To generate the validation data, we conducted field surveys in order to map the real trajectories of three boulders that were detached during a rockfall event that occurred on 1 December 2018. Our findings suggest that the use of low to medium-resolution DEMs translated into large errors in the shape of the simulated trajectories as well as the computed runout distances, which appeared to be exaggerated by such models. The geometry of the runout area and the targets of the potential rockfall events also appeared to be different from those mapped on the field. This hindered the efficiency of any prevention or correction measures. On the other hand, the 1m UAV-derived model produced more accurate results relative to the field data. Therefore, it is accurate enough for rockfall simulations and hazard research applications. Although such remote sensing techniques may require additional expenses, our results suggest that the enhanced accuracy of the models is worth the investment.Centre National de Recherche Scientifique et Technique of Morocco PPR2/205/65 projec

Internet y la primavera árabe: hacia una nueva percepción del ciberespacio

Internet and the Arab Spring: Towards a New Understanding of Cyberspace Abstract: The events of the Arab Spring have come to confirm the thesis that the Internet is no longer a simple creation of fun, or a phenomenon of life model that marks how came the technological progress of mankind. But it is a complex engineering, another world that flourished in parallel with the real world and feeds him a sixth continent which is added to the earth, a creation that metamorphosis to escape creator and become a world invested by the political and economic, market trade transactions, a tool for intercultural persuasion and an instrument of geopolitical and cold War. Keywords: Internet; Arab Revolutions; International Relations; Geopolitics; Cyberspace; Facebook; Twitter; Google.Resumen: Las Primaveras Árabes han venido a confirmar que Internet no es sólo un mero capricho tecnológico, o un fenómeno que refleja el nivel de progreso al que ha llegado la humanidad, sino un invento complejo. En cambio, se trata de un nuevo mundo virtual, como si un sexto continente hubiese sido añadido a la Tierra, que se ha desarrollado de forma paralela al mundo real y que se alimenta de él; y, finalmente, de una creación que se ha metamorfoseado para escaparse a su creador y convertirse en un nuevo ámbito en el que invierten los poderes políticos y económicos: un nuevo mercado para las transacciones comerciales, una herramienta de persuasión intercultural y un instrumento para la geopolítica y la guerra fría. Palabras clave: Internet; Revoluciones árabes; Relaciones internacionales; Geopolítica; ciberespacio; Facebook; Twitter; Google.Internet et le printemps arabe : vers une nouvelle perception de l'espace cybernétique Résumé : Les événements du printemps arabe ont venu confirmer la thèse selon laquelle, Internet n'est plus une simple création de plaisir, ou un phénomène de modèle vie qui marque à quel point est arrivé le progrès technologique de l'humanité. Mais c'est un génie-complexe, un autre monde qui s'épanouie en parallèle avec le monde réel et se nourrit de lui, un sixième continent qui vient s'ajouter au globe terrestre, une création qui se métamorphose pour s'échapper à son créateur et devenir un monde investi par le politique et l'économique, un marché de transactions commerciales, un outil de persuasion interculturel et un instrument de géopolitique et de guerre froide. Mots clés: Internet ; Révolutions arabes ; Relations internationales ; Géopolitique ; Cyberespace ; Facebook ; Twitter ; Google

Effect of Rockfall Spatial Representation on the Accuracy and Reliability of Susceptibility Models (The Case of the Haouz Dorsale Calcaire, Morocco)

Rockfalls can cause loss of life and material damage. In Northern Morocco, rockfalls and rock avalanche-deposits are frequent, especially in the Dorsale Calcaire morpho-structural unit, which is mostly formed by Jurassic limestone and dolostone formations. In this study, we focus exclusively on its northern segment, conventionally known as “the Haouz subunit”. First, a rockfall inventory was conducted. Then, two datasets were prepared: one covering exclusively the source area and the other representing the entirety of the mass movements (source + propagation area). Two algorithms were then used to build rockfall susceptibility models (RSMs). The first one (Logistic Regression: LR) yielded the most unreliable results, where the RSM derived from the source area dataset significantly outperformed the one based on the entirety of the rockfall affected area, despite the lack of significant visual differences between both models. However, the RSMs produced using Artificial Neural Networks (ANNs) were more or less similar in terms of accuracy, despite the source area model being more conservative. This result is unexpected given the fact that previous studies proved the robustness of the LR algorithm and the sensitivity of ANN models. However, we believe that the non-linear correlation between the spatial distribution of the rockfall propagation area and that of the conditioning factors used to compute the models explains why modeling rockfalls in particular differs from other types of landslides.CNRST within the framework of the research project PPR2/205/6

Internet y la primavera árabe: hacia una nueva percepción del ciberespacio

Las Primaveras Árabes han venido a confrmar que Internet no es sólo un mero capricho tecnológico, o un fenómeno que refleja el nivel de progreso al que ha llegado la humanidad, sino un invento complejo. En cambio, se trata de un nuevo mundo virtual, como si un sexto continente hubiese sido añadido a la Tierra, que se ha desarrollado de forma paralela al mundo real y que se alimenta de él; y, fnalmente, de una creación que se ha metamorfoseado para escaparse a su creador y convertirse en un nuevo ámbito en el que invierten los poderes políticos y económicos: un nuevo mercado para las transacciones comerciales, una herramienta de persuasión intercultural y un instrumento para la geopolítica y la guerra fría.Les événements du printemps arabe ont venu confrmer la thèse selon laquelle, Internet n’est plus une simple création de plaisir, ou un phénomène de modèle vie qui marque à quel point est arrivé le progrès technologique de l’humanité. Mais c’est un génie-complexe, un autre monde qui s’épanouie en parallèle avec le monde réel et se nourrit de lui, un sixième continent qui vient s’ajouter au globe terrestre, une création qui se métamorphose pour s’échapper à son créateur et devenir un monde investi par le politique et l’économique, un marché de transactions commerciales, un outil de persuasion interculturel et un instrument de géopolitique et de guerre froide.The events of the Arab Spring have come to confrm the thesis that the Internet is no longer a simple creation of fun, or a phenomenon of life model that marks how came the technological progress of mankind. But it is a complex engineering, another world that flourished in parallel with the real world and feeds him a sixth continent which is added to the earth, a creation that metamorphosis to escape creator and become a world invested by the political and economic, market trade transactions, a tool for intercultural persuasion and an instrument of geopolitical and cold War

Weak foliated rock slope stability analysis with ultra-close-range terrestrial digital photogrammetry

Este artículo ha sido financiado por el Grupo de Investigaciones Medioambientales: Riesgos Geológicos e Ingeniería del Terreno (RNM121) de la Junta de Andalucía y por proyecto de investigación "Desarrollo de técnicas para la regionalización de la peligrosidad de movimientos de ladera en la cuenca del río Genil y la cuenca Sur (Adra-Nerja) de la Cordillera Bética" (Ministerio de Educación y Ciencia del Gobierno de España).This paper presents a review of the data acquisition procedures of geotechnical parameters for rock slope stability assessment and the proposal of some new improvements. For this purpose, a piece of research based on the slope mass rating classification system using closerange terrestrial digital photogrammetry (CR-TDP) has led to improvements in quality and timing of discontinuity data acquisition, and analyzes the suitability of each one of the parameters when applied to weak foliated rocks. TDP allows rapid 3D image acquisition of a rock slope, which can be analyzed using software to determine the geometrical parameters that affect stability. A fast procedure to perform the photogrammetric, non-contact survey in order to obtain the 3D images is shown in this paper. Being a rapid and single-person task, this procedure provides enough precision to be applied to weak foliated rock slopes with non-well-defined geometry. Furthermore, the study has focused on highly foliated rock outcrops, in which high resolution in the 3D images is very desirable. This research was applied to mountain road cuts, in which the use of TDP with a very close range was necessary. Through an application on weak rocks in the Alpujarras (Andalusia, Spain), this work analyzes the bias when applying TDP to materials such as these, under progressive weathering processes.Junta de Andalucía (RNM121)Ministerio de Educación y Ciencia del Gobierno de Españ

A New Design of an UWB Circular Fractal Printed Antenna

A Microstrip Antenna (MSA) has been computed and analysed in this study by using CST of Microwave studio as Electromagnetic solver by generating the coefficient of reflection, the Gain, the density of current and the radiation pattern in the frequency range 3.1-10.6 GHz which commercialised by the Federal communication commission (FCC) as an Ultra-wide band (UWB) frequency range. The substrate used to achieve the proposed structure is the FR4-Epoxy with a thickness of 1.6 mm, a constant dielectric of 4.4 and a loss tangent of 0.025. The radiating patch is a circular shape etched with different sizes to create the fractal geometry. The transmission line has been designed by including a tapered section in the part connected to the radiator. The design of the antenna has been verified by using ADS and CST solvers. The fabrication of the antenna has been performed in order to measure the coefficient of reflection and the radiation pattern

Characterization and Analysis of Landslide Evolution in Intramountain Areas in Loja (Ecuador) Using RPAS Photogrammetric Products

This case study focuses on the area of El Plateado near the city of Loja, Ecuador, where landslides with a high impact on infrastructures require monitoring and control. The main objectives of this work are the characterization of the landslide and the monitoring of its kinematics. Four flights were conducted using a remotely piloted aerial vehicle (RPAS) to capture aerial images that were processed with SfM techniques to generate digital elevation models (DEMs) and orthoimages of high resolution (0.05 m) and sufficient accuracy (below 0.05 m) for subsequent analyses. Thus, the DEM of differences (DoD) and profiles are obtained, but a morphometric analysis is conducted to quantitatively characterize the landslide's elements and study its evolution. Parameters such as slope, aspect, topographic position index (TPI), terrain roughness index (TRI), and topographic wetness index (TWI) are analyzed. The results show a higher slope and roughness for scarps compared to stable areas and other elements. From TPI, slope break lines have been extracted, which allow the identification of landslide features such as scarps and toe tip. The landslide shows important changes in the landslide body surface, the retraction of the main scarp, and advances of the foot. A general decrease in average slope and TRI and an increase in TWI are also observed due to the landslide evolution and stabilization. The presence of fissures and the infiltration of rainfall water in the unsaturated soil layers, which consist of high-plasticity clays and silts, contribute to the instability. Thus, the study provides insights into the measurement accuracy, identification and characterization of landslide elements, morphometric analysis, landslide evolution, and the relationship with geotechnical factors that contribute to a better understanding of landslides. A higher frequency of the RPAS surveys and quality of geotechnical and meteorological data are required to improve the instability analysis together with a major automation of the GIS procedures.Private Technical University of Loja PROY_GMIC_128

Propuesta de evaluación del aprendizaje en materias científico-técnicas

El presente trabajo pretende mostrar un sistema de evaluación que se lleva acabo en materias científico-técnicas donde el contenido práctico es considerable. Se pretende considerar los distintos instrumentos y formas de evaluación del aprendizaje de los estudiantes. El objetivo principal de este trabajo pretende entender que examinar y calificar no son actos de menor importancia, sino que suponen una gran influencia en todo el proceso y pueden o no, ayudar y animar a los estudiantes en su principal tarea del aprendizaje y su progreso. La propuesta permite desarrollar las siguientes técnicas docentes: sesiones académicas teóricas, prácticas, exposición y debate, seminarios y jornadas, tutorías colectivas y además visitas facultativas

A low cost fractal CPW fed antenna for UWB applications with a circular radiating patch

In this study a validated antenna into simulation and through measurement has been described and analyzed. The coplanar waveguide (CPW) technique has been chosen to feed the radiating patch while the two ground planes have been partially designed in the top side of the substrate. The fractal geometry, applied to the circular radiator, has been obtained by merging the circular and rectangular shapes. The fiberglass FR-4, with a single side of 35μm copper thickness, has been used to achieve the antenna material with a permittivity of 4.4, a thickness of 1.6 mm, a loss tangent of 0.025 and an overall dimension of 34x43 mm2. The proposed CPW fractal antenna has been configured to operate in the frequency range 3.1-10.6 GHz published by the federal communications commission (FCC) as an ultra-wide band (UWB). To calculate the return loss, the gain, the current density and the radiation pattern of the simulated antenna, two electromagnetic solvers have been involved which are the CST microwave studio and ADS. The series of measurement have been performed by using the network analyzer and the anechoic chamber in order to confirm the computed antenna