Papers by Angel M Felicisimo
Digital Applications in Archaeology and Cultural Heritage
This bronze was found around 1969 in an area known as Tabla de las Cañas, near Capilla (Badajoz).... more This bronze was found around 1969 in an area known as Tabla de las Cañas, near Capilla (Badajoz). Unfortunately, no further details are known about the figure. It is currently kept in the National Archaeological Museum, with reference number 1972/45/1. From the archival documentation, also kept in the MAN, we know that in August 1972 the Spanish state decided to acquire it, at which point it entered the Museum (MAN 1972/45-6). At present it can be seen in Room 11, dedicated to Peninsular Protohistory.
Observing and interpreting: the Iberian world of the Museo Arqueológico Nacional in 3D: -Iberian ... more Observing and interpreting: the Iberian world of the Museo Arqueológico Nacional in 3D: -Iberian notebooks in 3D -The Dama de Galera -The Bicha de Balazote -The Gran Dama Oferente -The warriors' cup -Funerary urn -A female votive offeringProyecto Nacional de I+D+i (HAR2017-87897-P): Reubicando los objetos ibéricos del Museo Arqueológico Nacional: de rituales, biografías y observaciones a través de los modelos 3D. Este boletín se ha realizado con la ayuda del proyecto I+D+i «Lexicon iconográfico del mundo ibérico: las imágenes griegas» (HAR2013-47887-C2-1-P) financiado por el Ministerio de Economía, Industria y Competitividad.Peer reviewe
Universidad de Extremadura, Grupo de Investigación Kraken, 2021
HERITAGE DOCUMENTATION TECHNIQUES AND METHODS 3D models are digital replicas of a real object tha... more HERITAGE DOCUMENTATION TECHNIQUES AND METHODS 3D models are digital replicas of a real object that can be treated, represented and disseminated as any digital file.
Universidad de Extremadura, Centro Universitario de Mérida, 2017
This 3D scanning project was conducted within the framework of the collaborations between the Uni... more This 3D scanning project was conducted within the framework of the collaborations between the University Centre of Merida (through the CMPLab) and Consortium of the Monumental City of Merida. In this context, the end-of-degree works, meetings and conferences regarding the documentation and model construction through techniques such as photogrammetry, scanning and construction of virtual objects were performed. CMPLab is the acronym for Data Capture, Virtual Modelling and Production/Prototyping Laboratory. CMPLab emerged from a project of the Infrastructure and Scientific-Technical Equipment Aid from the Secretary of State for Research and began operating in 2016. This laboratory works on research areas related to the construction of 3D models of archaeological objects, very-high-resolution photography, geophysical prospecting and applications of geomatics to cultural heritage.
Universidad de Extremadura, Grupo de Investigación Kraken, 2021
Técnicas y métodos de documentación del patrimonio Los modelos 3D son réplicas digitales de un ob... more Técnicas y métodos de documentación del patrimonio Los modelos 3D son réplicas digitales de un objeto real que pueden ser tratadas, representadas y difundidas como cualquier archivo digital.
Presentacion del libro Actas del Congreso Internacional la Arqueologia Urbana en las Ciudades de ... more Presentacion del libro Actas del Congreso Internacional la Arqueologia Urbana en las Ciudades de la Hispania Romana: Proyectos Integrales de Investigacion, Conservacion y Difusion.
Global Ecology and Biogeography, 2019
Aim: Long-distance dispersal research in plants has long been dominated by the assumption that an... more Aim: Long-distance dispersal research in plants has long been dominated by the assumption that an association between plant diaspore adaptations and related transport vectors (standard dispersal) determines the success of colonization. However, the role of diaspore adaptations in a biogeographic context is being increasingly questioned, as evidence reveals that unspecialized plants have been successful colonizers by recurrent non-standard dispersal. We studied wind and oceanic currents as vectors for long-distance plant dispersal between the Americas and the Galápagos Islands with the focus on diaspore specializations to gain knowledge on the net contribution of standard and non-standard dispersal mechanisms. Location: Eastern Pacific Ocean: the American continent and Galápagos. Major taxa studied: Non-endemic angiosperms native to Galápagos and the American continent. Methods: We used connectivity models for prevailing wind and ocean currents based on satellite data to explore the correspondence between connectivity and species distribution patterns. Using a randomization test to eliminate the effect of wind and current directionality, we evaluated whether the proportion of species that is more connected than randomly expected varies for the five diaspore specialization groups. Results: We found that a large percentage of the plants are present in areas of the continent where ocean current connectivity with the archipelago is higher than expected by chance, while the percentage is small for areas with high wind connectivity. We did not find correspondence between species long-distance dispersal specialization and the connectivity provided by either of the two abiotic vectors. Main conclusions: Our results of ocean current connectivity-over wind connectivity-lead us to hypothesize that rafting dispersal has been significant in connecting the biota of Central/South America and the Galápagos Islands. This result supports a more prominent role of non-standard dispersal mechanisms in a biogeographic context than accepted in traditional schemes.
Historical Archaeology, 2017
Three-dimensional (3-D) models of archaeological artifacts can be obtained using free or low-cost... more Three-dimensional (3-D) models of archaeological artifacts can be obtained using free or low-cost image-based modeling (IBM) systems. IBM systems generate a 3-D model by processing a set of overlapping digital photographs of an object or scene. Sundials are generally located in inaccessible places, and photography may be the only method to study them. The purpose of this paper is to explore the potential of the 3-D modeling of archaeological objects obtained by IBM systems and embedded in a 3-D interactive portable document format (PDF) file. The process is illustrated by two case studies: a Roman sundial and a historical vertical sundial. The 3-D interactive PDF file allows for measuring some elements in the 3-D model. These measurements can be obtained easily and provide metric information about the sundials without touching them.
PLoS ONE, 2008
Global wind patterns influence dispersal and migration processes of aerial organisms, propagules ... more Global wind patterns influence dispersal and migration processes of aerial organisms, propagules and particles, which ultimately could determine the dynamics of colonizations, invasions or spread of pathogens. However, studying how windmediated movements actually happen has been hampered so far by the lack of high resolution global wind data as well as the impossibility to track aerial movements. Using concurrent data on winds and actual pathways of a tracked seabird, here we show that oceanic winds define spatiotemporal pathways and barriers for large-scale aerial movements. We obtained wind data from NASA SeaWinds scatterometer to calculate wind cost (impedance) models reflecting the resistance to the aerial movement near the ocean surface. We also tracked the movements of a model organism, the Cory's shearwater (Calonectris diomedea), a pelagic bird known to perform long distance migrations. Cost models revealed that distant areas can be connected through ''wind highways'' that do not match the shortest great circle routes. Bird routes closely followed the low-cost ''wind-highways'' linking breeding and wintering areas. In addition, we found that a potential barrier, the near surface westerlies in the Atlantic sector of the Intertropical Convergence Zone (ITCZ), temporally hindered meridional transequatorial movements. Once the westerlies vanished, birds crossed the ITCZ to their winter quarters. This study provides a novel approach to investigate wind-mediated movements in oceanic environments and shows that large-scale migration and dispersal processes over the oceans can be largely driven by spatiotemporal wind patterns.
Science, 2004
Anisotropic (direction-dependent) long-distance dispersal (LDD) by wind has been invoked to expla... more Anisotropic (direction-dependent) long-distance dispersal (LDD) by wind has been invoked to explain the strong floristic affinities shared among landmasses in the Southern Hemisphere. Its contribution has not yet been systematically tested because of the previous lack of global data on winds. We used global winds coverage from the National Aeronautics and Space Administration SeaWinds scatterometer to test whether floristic similarities of Southern Hemisphere moss, liverwort, lichen, and pteridophyte floras conform better with (i) the anisotropic LDD hypothesis, which predicts that connection by “wind highways” increases floristic similarities, or (ii) a direction-independent LDD hypothesis, which predicts that floristic similarities among sites increase with geographic proximity. We found a stronger correlation of floristic similarities with wind connectivity than with geographic proximities, which supports the idea that wind is a dispersal vehicle for many organisms in the Souther...
Journal of Vegetation Science, 2004
Logistic Multiple Regression, Principal Component Regression and Classification and Regression Tr... more Logistic Multiple Regression, Principal Component Regression and Classification and Regression Tree Analysis (CART), commonly used in ecological modelling using GIS, are compared with a relatively new statistical technique, Multivariate Adaptive Regression Splines (MARS), to test their accuracy, reliability, implementation within GIS and ease of use. All were applied to the same two data sets, covering a wide range of conditions common in predictive modelling, namely geographical range, scale, nature of the predictors and sampling method. We ran two series of analyses to verify if model validation by an independent data set was required or cross-validation on a learning data set sufficed. Results show that validation by independent data sets is needed. Model accuracy was evaluated using the area under Receiver Operating Characteristics curve (AUC). This measure was used because it summarizes performance across all possible thresholds, and is independent of balance between classes. MARS and Regression Tree Analysis achieved the best prediction success, although the CART model was difficult to use for cartographic purposes due to the high model complexity.
IEEE Transactions on Geoscience and Remote Sensing, 2005
The aim of this communication is to study the accuracy and reliability of digital elevation model... more The aim of this communication is to study the accuracy and reliability of digital elevation models (DEMs) generated from two different satellite sources [the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)] and [the Systeme P'our l'Observation de la Terre (SPOT) High Resolution Visible (HRV)] stereoscopic images), using three different photogrammetric softwares. The main reason of the study is the heterogeneity and absence of agreement found in previous research concerning several significant aspects of DEM generation methods. A set of 91 DEMs were generated from SPOT data and 55 DEMs from ASTER data. Error control was performed with 315 check points determined by differential global positioning systems. Results of Terra ASTER DEMs show that elevation RMSE (root mean square error) equals 13.0 m. The corresponding RMSE value for SPOT HRV DEM is 7.3 m. In both cases, the error is less than the pixel size. Furthermore, this communication proposes a technique to improve DEM structure, based on an objective criterion to cleanse redundancy in DEMs without a significant loss of accuracy. This criterion is based on removing all points with a correlation value below a threshold value.
IEEE Transactions on Geoscience and Remote Sensing, 2006
Remote sensors have begun to capture digital stereoscopic data. Although still monospectral (usua... more Remote sensors have begun to capture digital stereoscopic data. Although still monospectral (usually panchromatic), the capture of multispectral or hyperspectral stereoscopic data is just a matter of time. Digital photogrammetric workstations use area-based stereo-matching techniques based on the Pearson (product-moment) correlation coefficient. This is a technique that is not intended to take advantage of the multispectral data. The authors propose a new method that 1) can handle this multispectral information and 2) can take advantage of the spatial relations between pixel locations. The method is based on multidimensional scaling and Procrustes analysis. Our results indicate that the proposed new technique renders more robust results than classical methodology when noise in the original data is introduced.
IEEE Transactions on Geoscience and Remote Sensing, 2012
IEEE Geoscience and Remote Sensing Letters, 2014
ABSTRACT Circular or directional data are used in disciplines such as meteorology, geomatics, bio... more ABSTRACT Circular or directional data are used in disciplines such as meteorology, geomatics, biology, and geology. The analysis of angular data requires special methods that are available in some statistical packages. However, these tools analyze only the angular values and do not include the vector modules, assuming unit vectors in all cases. In this letter, an open-source graphic and statistical package, i.e., VecStatGraphs2D, is described. It Works in the R environment and provides statistics and graphics for modules (linear) and azimuths (circular), as well as graphics for the joint analysis of modules and azimuths. QuikSCAT satellite wind data are used to demonstrate some features of the package. QuikSCAT data are non-unit-length vectors, where both azimuth and magnitude (speed) are derived from u and v vector components (vector projections over the x- and y-axes). The example is used to show the seasonal change of winds in the Intertropical Convergence Zone, a key area in the ocean bird migration from the North to South Atlantic oceans.
IEEE Geoscience and Remote Sensing Letters, 2014
ABSTRACT The use of spherical statistics for comparing and analyzing different digital elevation ... more ABSTRACT The use of spherical statistics for comparing and analyzing different digital elevation models (DEMs) is proposed in this letter by the new software package VecStatGraphs3D. Spherical data deal with angular data such as unit vector in 3-D space and are used in disciplines such as meteorology, geomatics, biology, and geology. Usually, the most common descriptor to analyze DEMs is the root-mean-square error (linear statistic), but this statistic itself cannot describe the error positional distributions. Comparing homologous points in two different DEMs generates 3-D vectors, which can be analyzed by means of spherical statistics. A 3-D vector is defined by its module (linear statistics) and colatitude and longitude (spherical statistics). While several graphical and statistical tools are available for the analysis of directional data in 3-D, these tools consider only the angular magnitude and work with unit vectors. In this letter, the open-source software package VecStatGraphs3D is described. It works in the R environment and provides statistics for modules (linear), colatitude and longitude (spherical), and graphics for the joint analysis of 3-D vectors. The spatial locations of singular points between two DEMs of different spatial resolution: LIDAR (5 m) and ASTER Global Digital Elevation Map (30 m) are compared as examples using VecStatGraphs3D. The interactive 3-D graphics reveal spatial patterns and assist in understanding the effect of the DEM resolution on the uncertainty of the spatial locations of relief.
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Papers by Angel M Felicisimo