Análisis y evaluación de riesgos de incidencias naturales en el sistema productivo agrario intensivo de Almería

Fecha de defensa:

2011

Doctorando:

Carlos Fernández Sierra

Directores:

Fernando Carvajal Ramírez

Francisco Agüera Vega

Jerónimo José Pérez Parra

https://www.educacion.gob.es/teseo/mostrarRef.do?ref=1039563

RESUMEN

La estructura del invernadero es el elemento cualitativamente más importante de la explotación superintensiva predominante en la provincia de Almería, y del que depende en gran medida la capacidad productiva de la misma. A su vez, es el elemento que libera la producción agrícola del azar meteorológico.

Desde el punto de vista económico, la inversión que representa la construcción o mejora de un invernadero, es elevada. Por este motivo, asegurar las estructuras de los invernaderos se antoja como una auténtica necesidad a la hora de garantizar al agricultor su medio de vida.

La Tesis Doctoral se circunscribe dentro del área de estudios para desarrollar las nuevas coberturas previstas tras la modificación de la Ley de seguros agrarios relativas a daños sobre instalaciones y medios elementos productivos de la parcela.

Se estudia el escenario actual de los seguros agrarios, y en particular la situación actual del seguro de estructuras de invernaderos. Posteriormente se analizan los daños, según estudios anteriores de siniestralidad, de las causas que producen estos daños. Se hace un estudio estructural de los elementos que componen el invernadero, efectos cualitativos y magnitud de dichos daños. A raíz de estos datos, se elabora un modelo basado en un sistema de  scoring, base de datos alimentada por visitas técnicas de campo a distintas explotaciones. De esta manera, se realiza una selección de riesgos teniendo en cuenta diferentes variables técnicas que nos capacita a la hora de discernir entre la asegurabilidad o no de distintas estructuras de invernadero. Por último, se caracteriza el parque de invernaderos de la provincia de Almería en relación a la asegurabilidad de los mismos

Measuring sunflower nitrogen status from an unmanned aerial vehicle-based system and an on the ground device

Francisco Agüera Vega, Fernando Carvajal Ramírez, Mónica Pérez Saiz 2011 UAV-g 2011. International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences – ISPRS Archives 38: 201-206 http://www.scopus.com/inward/record.url?eid=2-s2.0-84924042320&partnerID=MN8TOARS ABSTRACT Precision agriculture recognizes the inherent spatial variability associated with soil characteristics, land morphology and crop growth, and uses this information to prescribe the most appropriate […]

Surveying a landslide in a road embankment using unmanned aerial vehicle Photogrammetry

Fernando Carvajal Ramírez, Francisco Agüera Vega, Mónica Pérez Saiz

2011

UAV-g 2011. International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences – ISPRS Archives 38: 201-206

http://www.scopus.com/inward/record.url?eid=2-s2.0-84924056936&partnerID=MN8TOARS

ABSTRACT

Most of the works of civil engineering, and some others applications, need to be designed using a basic cartography with a suitable scale to the accuracy and extension of the plot. The Unmanned Aerial Vehicle (UAV) Photogrammetry covers the gap between classical manned aerial photogrammetry and hand-made surveying techniques because it works in the close-range domain, combining aerial and terrestrial photogrammetry, but also introduces low-cost alternatives. The aim of this work is developing of an accurate and low-cost method to characterize landslides located on the size of a road. It was applied at the kilometric point 339 belonging to the A92 dual carriageway, in the Abla municipal term, province of Almeria, Spain. A photogrammetric project was carried out from a set of images taken from an md4-200 Microdrones with an on-board calibrated camera 12 Megapixels Pentax Optio A40. The flight was previously planned to cover the whole extension of the embankment with three passes composed of 18 photos each one. All the images were taken with the vertical axe and it was registered 85% and 60% longitudinal and transversal overlaps respectively. The accuracy of the products, with planimetric and altimetric errors of 0.049 and 0.108m repectively, lets to take measurements of the landslide and projecting preventive and palliative actuations.

Digital camera calibration using images taken from an unmanned aerial vehicle

Mónica Pérez Saiz, Francisco Agüera Vega, Fernando Carvajal Ramírez

2011

UAV-g 2011. International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences – ISPRS Archives 38: 167-171

http://www.scopus.com/inward/record.url?eid=2-s2.0-84924067582&partnerID=MN8TOARS

ABSTRACT

For calibrating the camera, an accurate determination of the interior orientation parameters is needed. For more accurate results, the calibration images should be taken under conditions that are similar to the field samples. The aim of this work is the establishment of an efficient and accurate digital camera calibration method to be used in particular working conditions, as it can be found with our UAV (Unmanned Aerial Vehicle) photogrammetric projects. The UAV used in this work was md4-200 modelled by Microdrones. The microdrone is also equipped with a standard digital non-metric camera, the Pentax Optio A40 camera. To find out the interior orientation parameters of the digital camera, two calibration methods were done. A lab calibration based on a flat pattern and a field calibration were fulfilled. To carry out the calibration, Photomodeler Scanner software was used in both cases. The lab calibration process was completely automatic using a calibration grid. The focal length was fixed at widest angle and the network included a total of twelve images with ± 90° roll angles. In order to develop the field calibration, a flight plan was programmed including a total of twelve images. In the same way as in the lab calibration, the focal length was fixed at widest angle. The field test used in the study was a flat surface located on the University of Almería campus and a set of 67 target points were placed. The calibration field area was 25 x 25 m approximately and the altitude flight over ground was 50 m. After the software processing, the camera calibration parameter values were obtained. The paper presents the process, the results and the accuracy of these calibration methods. The field calibration method reduced the final total error obtained in the previous lab calibration. Furthermore the overall RMSs obtained from both methods are similar. Therefore we will apply the field calibration results to all our photogrammetric projects in which the flight high will be close to 50 m.