130 resultados para Photogrammetric
Resumo:
Topographic data of this geological map were obtained through stereoscopic aerial photo interpretation. The photogrammetric photo flights were undertaken in 1986 by the Institut für Angewandte Geodäsie, Frankfurt. Horizontal ground control points required for aerial photo interpretation were determined by means of Doppler satellite observation during the 2nd German Neuschwabenland Expedition 1985/86. Vertical ground control points were taken from unpublished map drafts at 1:100 000 scale by Norsk Polarinstitutt, Oslo. The elevation above mean sea level was transferred to Heimefrontfjella barometrically. For this reason assertions concerning the absolute elevation (referred to sea level) are uncertain. Contours and spot heights presented on the map were obtained from the photogrammetric evaluation of the photography taken in 1986; relative elevation data (hight differences) are accurate to approximately ±10 m.
Resumo:
Photogrammetric surveys have been made and maps drawn of a number of glaciers in the eastern Alps, among them the Waxeggkees in the Zillertal Alps of Tyrol, at approximately ten-year intervals since 1950. Terrestrial photogrammetry was used for the pictures taken in 1950, 1960, 1980, 1989 and 2000, while aerial photogrammetry was employed for the 1969 photo. These maps were subsequently used to calculate the changes in area, elevation and volume for elevational zones of 50 m. The numeric values are given in two tables. The illustration of surface changes in Waxeggkees is continued cartographically on 5 map sheets at the scale of 1 : 15.000 and a vertical interval of the contour lines of 50 m. Changes in glacier area are marked in light red to indicate a decrease in area, and in light blue for an increase. Changes in elevation can only be indicated indirectly, namely in the form of vertical interval bands, referring to the surface areas that arise due to the relocation of the contour lines, resulting from an elevational change. Decrease in elevation is indicated in red, increase in blue, on 100 m contour lines.
Resumo:
The map covers the Cathedral Massif Glacier with its proglacial area and the surrounding terrain - altogether an area of about 5.2 square kilometers. The small cirque glacier is located in the Cathedral Massif on the continental slope of the northern Boundary Range in British Columbia, Canada. The field survey and the terrestrial photogrammetry was carried out in July 1977. In addition aerial photos taken in August 1975 were used for the photogrammetric plotting. Due to the lack of connection with the official Canadian geodetic net, a local net was used. The main objective of the mapping was to document the present-day glacier with its specific topographical features of the forefield. The map is printed in five colours in offset. The surface area of the glacier was 1.71 square kilometers in 1977 and has further reduced since then. During the stage of "maximum" neoglacial extend, the glacier area must have been close to 2.8 square kilometers.
Resumo:
Topographic data of this geological map were obtained through stereoscopic aerial photo interpretation. The photogrammetric photo flights were undertaken in 1986 by the Institut für Angewandte Geodäsie, Frankfurt. Horizontal ground control points required for aerial photo interpretation were determined by means of Doppler satellite observation during the 2nd German Neuschwabenland Expedition 1985/86. Vertical ground control points were taken from unpublished map drafts at 1:100 000 scale by Norsk Polarinstitutt, Oslo. The elevation above mean sea level was transferred to Heimefrontfjella barometrically. For this reason assertions concerning the absolute elevation (referred to sea level) are uncertain. Contours and spot heights presented on the map were obtained from the photogrammetric evaluation of the photography taken in 1986; relative elevation data (hight differences) are accurate to approximately ±10 m.
Resumo:
During the summer of 2004, the front area of the Jakobshavn Isbræ was monitored using a geodetic-photogrammetric survey with temporarily coincident precise observations of local ocean tides in the Disko Bay close to Ilulissat. The geodetic and photogrammetric observations were conducted at the southern margin of the glacier front. The largest observed horizontal flow velocities are in the central part of the front with values up to 45 m/d. This is a factor of 2 greater than the average velocities at the front area observed in the last century. Our new observations confirm previous estimates of an acceleration of glacier flow during the last decade. The photogrammetric survey provided flow trajectories for 4000 surface points with a time resolution of 30 min. These flow trajectories were used to compare the vertical motion of the glacier with the observed tides. The existence of a free-floating glacier tongue in 2004 was confirmed by these data. However, it occupied only a small belt, of at most a few 100 m width, in the central part of the glacier front. Horizontal motion did not appear to depend on the tidal phase, unlike some of the fast-moving ice streams of West Antarctica.
Resumo:
The study of glacier fronts combines different geomatics measurement techniques as the classic survey using total station or theodolite, technical GNSS (Global Navigation Satellite System), using laser-scanner or using photogrammetry (air or ground). The measure by direct methods (classical surveying and GNSS) is useful and fast when accessibility to the glaciers fronts is easy, while it is practically impossible to realize, in the case of glacier fronts that end up in the sea (tide water glaciers). In this paper, a methodology that combines photogrammetric methods and other techniques for lifting the front of the glacier Johnsons, inaccessible is studied. The images obtained from the front, come from a non-metric digital camera; its georeferencing to a global coordinate system is performed by measuring points GNSS support in accessible areas of the glacier front side and applying methods of direct intersection in inaccessible points of the front, taking measurements with theodolite. The result of observations obtained were applied to study the temporal evolution (1957-2014) of the position of the Johnsons glacier front and the position of the Argentina, Las Palmas and Sally Rocks lobes front (Hurd glacier).
Resumo:
In this paper, a new high-resolution elevation model of Greenland, including the ice sheet as well as the ice free regions, is presented. It is the first published full coverage model, computed with an average resolution of 2 km and providing an unprecedented degree of detail. The topography is modeled from a wide selection of data sources, including satellite radar altimetry from Geosat and ERS 1, airborne radar altimetry and airborne laser altimetry over the ice sheet, and photogrammetric and manual map scannings in the ice free region. The ice sheet model accuracy is evaluated by omitting airborne laser data from the analysis and treating them as ground truth observations. The mean accuracy of the ice sheet elevations is estimated to be 12-13 m, and it is found that on surfaces of a slope between 0.2° and 0.8°, corresponding to approximately 50% of the ice sheet, the model presents a 40% improvement over models based on satellite altimetry alone. On coastal bedrock, the model is compared with stereo triangulated reference points, and it is found that the model accuracy is of the order of 25-35 m in areas covered by stereo photogrammetry scannings and between 200 and 250 m elsewhere.
Resumo:
Topographic data of this geological map were obtained through stereoscopic aerial photo interpretation. The photogrammetric photo flights were undertaken in 1986 by the Institut für Angewandte Geodäsie, Frankfurt. Horizontal ground control points required for aerial photo interpretation were determined by means of Doppler satellite observation during the 2nd German Neuschwabenland Expedition 1985/86. Vertical ground control points were taken from unpublished map drafts at 1:100 000 scale by Norsk Polarinstitutt, Oslo. The elevation above mean sea level was transferred to Heimefrontfjella barometrically. For this reason assertions concerning the absolute elevation (referred to sea level) are uncertain. Contours and spot heights presented on the map were obtained from the photogrammetric evaluation of the photography taken in 1986; relative elevation data (hight differences) are accurate to approximately ±10 m.
Resumo:
Topographic data of this geological map were obtained through stereoscopic aerial photo interpretation. The photogrammetric photo flights were undertaken in 1986 by the Institut für Angewandte Geodäsie, Frankfurt. Horizontal ground control points required for aerial photo interpretation were determined by means of Doppler satellite observation during the 2nd German Neuschwabenland Expedition 1985/86. Vertical ground control points were taken from unpublished map drafts at 1:100 000 scale by Norsk Polarinstitutt, Oslo. The elevation above mean sea level was transferred to Heimefrontfjella barometrically. For this reason assertions concerning the absolute elevation (referred to sea level) are uncertain. Contours and spot heights presented on the map were obtained from the photogrammetric evaluation of the photography taken in 1986; relative elevation data (hight differences) are accurate to approximately ±10 m.
Resumo:
The Austrian glacier inventory 1969 was compiled from airborne photogrammetry dating from September and October 1969. It includes not only area and surface elevation, but also a number of other parameters as aspect, maximum and minimum elevation, position, ablation and accumulation area. The dataset published here are the orginal results. In course of the compilation of the second Austrian glacier inventory, the photogrammetric data partly has been reanalysed. While in this data set snow areas connected to the glaciers and snow patches in the upper parts of the glacier have not been added to the glacier area, the second glacier inventory included the snow patches.
Resumo:
La presente tesis doctoral describe los desarrollos realizados, y finalmente materializados en patentes con registro de la propiedad intelectual, para la integración de las nuevas tecnologías de documentación fotogramétrica y las bases de datos de los barredores láser terrestres, en los procesos de elaboración, redacción y ejecución de proyectos de restauración y rehabilitación arquitectónicos. Los avances tecnológicos aparecidos en control métrico, junto con las técnicas de imagen digital y los desarrollos fotogramétricos, pueden aportar mejoras significativas en el proceso proyectual y permiten aplicar nuevos procedimientos de extracción de datos para generar de forma sencilla, bajo el control directo y supervisión de los responsables del proyecto, la información métrica y documental más adecuada. Se establecen como principios, y por tanto como base para el diseño de dicha herramienta, que los desarrollos aparecidos sí han producido el uso extendido del sistema CAD (como instrumento de dibujo) así como el uso de la imagen digital como herramienta de documentación. La herramienta a diseñar se fundamenta por tanto en la imagen digital (imágenes digitales, imágenes rectificadas, ortofotografías, estéreo- modelos, estereo- ortofotografías) así como su integración en autocad para un tratamiento interactivo. En la aplicación de la fotogrametría a la disciplina arquitectónica, se considera de interés estructurar aplicaciones con carácter integrador que, con mayores capacidades de interactuación y a partir de información veraz y rigurosa, permitan completar o elaborar documentos de interés proyectual, ABSTRACT This doctoral thesis explains the developments carried out, and finally patented with intellectual property rights, for the integration of the new photogrammetric technology documentation and terrestrial scanner databases in the preparation, documentation and implementation processes of restoration projects and architectural renovation. The technological advances in metric control, as well as the digital image techniques and photogrammetric developments, can together bring a significant improvement to the projecting process, and, under the direct control and supervision of those in charge of the project, can allow new data extraction processes to be applied in order to easily generate the most appropriate metric information and documentation. The principles and, therefore, the basis for the design of this tool are that the developments have indeed produced the widespread use of the CAD system (as a drawing instrument) and the use of digital images as a documentation tool. The tool to be designed is therefore based on digital images (rectify images, orthophotos, stereomodels, stereo-orthophotos) as well as its integration in Autocad for interactive processing. In the application of photogrammetry to the architectural discipline, what interests us is to structure applications of an integrative nature which, with a greater capacity for interaction and from accurate and thorough information, enable the completion or elaboration of documents that are of interest to the project.
Resumo:
El principal objetivo de la presente investigación fue el conocer el perfil de rendimiento técnico de los triatletas, desde un punto de vista biomecánica, en el segmento carrera a pie durante la competición en triatlón. Asimismo, como el genero y el nivel deportivo del triatleta podrían influir en su respuesta motriz durante la competicion. Para ello, se necesitaba desarrollar y validar una técnica experimental que fuera lo suficientemente precisa (validez interna), con una alta fiabilidad y con una gran validez externa (ecologica) debido al entorno de la competicion. La muestra la formaron un total de 64 deportistas: 32 triatletas participantes en la Copa del Mundo de Triatlon de Madrid-2008 (16 hombres y 16 mujeres) y 32 triatletas participantes en el Clasificatorio del Campeonato de Espana Elite (16 hombres y 16 mujeres). El análisis de la técnica de carrera de los deportistas se realizo mediante un sistema fotogramétrico en 2d que permitió calcular las coordenadas (x,y) de los centros articulares con un error de 1.66% en el eje x y de un 2.10% en el eje y. Las imágenes fueron obtenidas por una cámara que filmaba el movimiento en un plano antero-posterior del triatleta. Algoritmos basados en la DLT (Abdel-Aziz & Karara, 1971) permitieron conocer las coordenadas reales a partir de las coordenadas digitalizadas en el plano y posteriormente las distintas variables analizadas. El análisis biomecánica de la carrera se realizo en 4 ocasiones diferentes durante la competición, correspondiendo con cada una de las vueltas de 2,5 km, que el triatleta tenía que realizar. La velocidad de carrera resulto estar íntimamente ligada al nivel deportivo del triatleta. Del mismo modo, 3 de los 4 grupos analizados presentaron valores inferiores a 3 minutos 30 segundos por kilometro recorrido, poniendo de manifiesto el altísimo nivel de los sujetos analizados. Del mismo modo parece que las chicos consiguen una mayor velocidad gracias a una mayor longitud de ciclo en relación a las chicas, ya que estas muestran valores mayores en cuanto a frecuencia de zancada. La frecuencia de zancada presento los valores más altos en la primera vuelta en todos los deportistas analizados. Asimismo, los triatletas de nivel internacional y las chicas fueron los que mostraron los mayores valores. La longitud de zancada presento distintas tendencias en función del nivel y el género del deportista. Así pues, en los deportistas internacionales y en los chicos los mayores valores se encontraron en la primera vuelta mientras que la tendencia fue al descenso, siendo probablemente la fatiga acumulada la causante de dicha tendencia. En cambio, aquellos deportistas de nivel nacional y las chicas mostraron valores mayores en la segunda vuelta que en la primera, evidenciando que además de la fatiga, el ciclismo previo tiene una incidencia directa sobre su rendimiento. Los tiempos de vuelo permanecieron constantes durante toda la carrera, encontrando cierta evolución en los tiempos de apoyo, la cual provoca una modificación en los porcentajes relativos en los tiempos de vuelo. Los tiempos de apoyo más bajos se encontraron en la primera vuelta. Del mismo modo, los deportistas de nivel internacional y los chicos mostraron valores inferiores. También, estos grupos fueron más constantes en sus valores a lo largo de las vueltas. Por el contrario, se encontraron tendencias al aumento en los triatletas de nivel nacional y en las chicas, los cuales no fueron capaces de mantener el mismo rendimiento debido seguramente a su menor nivel deportivo. La oscilación vertical de la cadera se mostro constante en los triatletas de mayor nivel, encontrándose tendencias al aumento en los de menor nivel. Del mismo modo, los valores más altos correspondieron a las chicas y a los deportistas de nivel nacional. La distancia de la cadera al apoyo permaneció constante a lo largo de las vueltas en todos los grupos, obteniéndose valores mayores en los triatletas de nivel internacional y en los chicos. El ángulo de la rodilla apoyada en el momento del despegue no mostro una tendencia clara. Los deportistas de nivel internacional y los chicos presentaron los valores más bajos. El ángulo de la rodilla libre en el momento del despegue mostro una correlación muy alta con la velocidad de carrera. Del mismo modo, los ángulos más pequeños se encontraron en los triatletas internacionales y en los chicos, debido seguramente a los mayores valores de velocidad registrados por ambos grupos. Los ángulos de los tobillos no mostraron ninguna tendencia clara durante la competición analizada. Los cuatro grupos de población presentaron valores similares, por lo que parece que no representan una variable que pueda incidir sobre el rendimiento biomecánica del triatleta. Los resultados obtenidos en el presente estudio de investigación avalan la utilización de la fotogrametría-video en 2d para el análisis de la técnica de carrera durante la competición en triatlón. Su aplicación en una competición de máximo nivel internacional ha posibilitado conocer el perfil técnico que presentan los triatletas a lo largo del segmento de carrera a pie. Del mismo modo, se ha podido demostrar como los estudios realizados en laboratorio no reflejan la realidad competitiva de un triatlón de máximo nivel. The aim of this research was to determine the running technique profile during a triathlon competition from a biomechanical perspective. Also, to analyze the triathlete gender’s and level of performance’s influence on this profile in competition. An accurate (internal validity) and reliable methodology with a high external validity (ecological) had to be developed to get those aims in competition. Sixty-four triathletes were analyzed. 32 (16 males, 16 females) took part in the Madrid 2008 Triathlon World Cup and 32 (16 males and 16 females) took part in the Spanish Triathlon National Championships. The biomechanical analyses were carried out by a photogrammetric system that allow to calculate the landmarks coordinates (x,y) with a 1.66% error in x axis, and a 2.10% error in y axis. The frames were obtained with a camera situated perpendicular to the triathletes’ trajectory, filming the saggittal plane. DLT based algorithms (Abdel-Aziz & Karara, 1971) were used to calculate the real coordinates from the digitalized ones and the final variables afterwards. The biomechanical analisys itself was performed in four different moments during the competition, according to each 2.5 km lap the triathletes had to do. Running speed was highly related to performance level. Also, 3 of the 4 analyzed groups showed speed values under the 3 minutes and 30 seconds per kilometer. It demonstrated the very high performance level of the analized triathletes. Furthermore, it seems that men get higher speeds because their longer stride length, while women shows higher stride frequency values. The highest stride frequency values were found in the first lap. Women and the international level triathletes showed the highest values. Stride length showed different tendencies according to the gender and level of performance. Men and international level triathletes showed the highest level in the first lap and a decreasing tendency after that. The accumulated fatigue was probably the reason of this tendency. On the other hand, higher values than in first lap were found in the second one in women and national level triathletes. It demonstrated the previous cycling can affect to those groups in terms of biomechanics. Flight times remained constant during the running part, while the contact times showed an increasing tendency that caused a variation in flight times percents. The lowest contact times were found in the first lap and in men and international triathletes’ values. Also, these two groups were more consistent during the whole running. On the other hand, increasing tendencies were found in women and national level triathletes, who were not able to maintain the same values probably due to their lower level of performance. Higher level triathletes showed more consistent hip vertical oscillation values than lower level triathletes, who presented increasing tendencies. The highest values were found in women and national level triathletes. The horizontal distance hip-toe cap remained constant among the laps in all the groups. Men and international level triathletes showed the highest values. The support knee angle at toe-off did not show a clear tendency. The lowest values were found in men and international level triathletes. A high correlation was found between the non-support knee angle and the running speed. Furthermore, men and international level triathletes showed the smallest values, due to the higher velocities reached by these two groups. Ankles angles did not show any tendency during the running part. Similar values were found in the four analyzed groups, so this variable does not seem to represent an important one within the triathlete’s performance. The results obtained in the present research support the use of the bidimensional photogrammetric video-system to analyze the running technique during a triathlon competition. Its application in international triathlon meetings has allowed determining the triathletes’ technique profile during the running part. Also, it has been demonstrated the laboratory-based studies does not reproduce a top-level competition.
Resumo:
Clasificación de una imagen de alta resolución "Quickbird" con la técnica de análisis de imágenes en base a objetos
Resumo:
The integration of correlation processes in design systems has as a target measurements in 3D directly and according to the users criteria in order to generate the required database for the development of the project. In the phase of photogrammetric works, internal and external orientation parameters are calculated and stereo models are created from standard images. The aforementioned are integrated in the system where the measurement of the selected items is done by applying developed correlation algorithms. The processing period has the tools to carry out the calculations in an easy and automatic way, as well as image measurement techniques to acquire the most correct information. The proposed software development is done on Visual Studio platforms for PC, applying the most apt codes and symbols according to the terms of reference required for the design. The results of generating the data base in an interactive way with the geometric study of the structures, facilitates and improves the quality of the works in the projects.
Resumo:
La utilización de una cámara fotogramétrica digital redunda en el aumento demostrable de calidad radiométrica debido a la mejor relación señal/ruido y a los 12 bits de resolución radiométrica por cada pixel de la imagen. Simultáneamente se consigue un notable ahorro de tiempo y coste gracias a la eliminación de las fases de revelado y escaneado de la película y al aumento de las horas de vuelo por día. De otra parte, el sistema láser aerotransportado (LIDAR - Light Detection and Ranging) es un sistema con un elevado rendimiento y rentabilidad para la captura de datos de elevaciones para generar un modelo digital del terreno (MDT) y también de los objetos sobre el terreno, permitiendo así alcanzar alta precisión y densidad de información. Tanto el sistema LIDAR como el sistema de cámara fotogramétrica digital se combinan con otras técnicas bien conocidas: el sistema de posicionamiento global (GPS - Global Positioning System) y la orientación de la unidad de medida inercial (IMU - Inertial Measure Units), que permiten reducir o eliminar el apoyo de campo y realizar la orientación directa de los sensores utilizando datos de efemérides precisas de los satélites. Combinando estas tecnologías, se va a proponer y poner en práctica una metodología para generación automática de ortofotos en países de América del Sur. Analizando la precisión de dichas ortofotos comparándolas con fuente de mayor exactitud y con las especificaciones técnicas del Plan Nacional de Ortofotografía Aérea (PNOA) se determinará la viabilidad de que dicha metodología se pueda aplicar a zonas rurales. ABSTRACT Using a digital photogrammetric camera results in a demonstrable increase of the radiometric quality due to a better improved signal/noise ratio and the radiometric resolution of 12 bits per pixel of the image. Simultaneously a significant saving of time and money is achieved thanks to the elimination of the developing and film scanning stages, as well as to the increase of flying hours per day. On the other hand, airborne laser system Light Detection and Ranging (LIDAR) is a system with high performance and yield for the acquisition of elevation data in order to generate a digital terrain model (DTM), as well as objects on the ground which allows to achieve high accuracy and data density. Both the LIDAR and the digital photogrammetric camera system are combined with other well known techniques: global positioning system (GPS) and inertial measurement unit (IMU) orientation, which are currently in a mature evolutionary stage, which allow to reduce and/or remove field support and perform a direct guidance of sensors using specific historic data from the satellites. By combining these technologies, a methodology for automatic generation of orthophotos in South American countries will be proposed and implemented. Analyzing the accuracy of these orthophotos comparing them with more accurate sources and technical specifications of the National Aerial Orthophoto (PNOA), the viability of whether this methodology should be applied to rural areas, will be determined.