Alberto Varela - Academia.edu (original) (raw)
Papers by Alberto Varela
ISPRS International Journal of Geo-Information, 2019
Naturalistic driving can generate huge datasets with great potential for research. However, to an... more Naturalistic driving can generate huge datasets with great potential for research. However, to analyze the collected data in naturalistic driving trials is quite complex and difficult, especially if we consider that these studies are commonly conducted by research groups with somewhat limited resources. It is quite common that these studies implement strategies for thinning and/or reducing the data volumes that have been initially collected. Thus, and unfortunately, the great potential of these datasets is significantly constrained to specific situations, events, and contexts. For this, to implement appropriate strategies for the visualization of these data is becoming increasingly necessary, at any scale. Mapping naturalistic driving data with Geographic Information Systems (GIS) allows for a deeper understanding of our driving behavior, achieving a smarter and broader perspective of the whole datasets. GIS mapping allows for many of the existing drawbacks of the traditional method...
ISPRS international journal of geo-information, Dec 29, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Computer-Aided Civil and Infrastructure Engineering
Sustainability
This study aimed to investigate the relationship between the characteristics of the areas of infl... more This study aimed to investigate the relationship between the characteristics of the areas of influence of bus stops and the decrease in ridership during COVID-19 lockdowns and subsequent initial reopening processes. A novel GIS methodology was developed to determine these characteristics from a large amount of data with high spatial detail and accurately assign them to individual bus stops. After processing the data, several multiple linear regression models were developed to determine the variables related to different activities and changes in mobility during lockdown that may explain the variation in demand owing to the COVID-19 pandemic. The characteristics related to population and land use were also studied. The proposed methodology can be used to improve transit planning during exceptional situations, by strengthening public transport in areas with a predictably higher transit demand, instead of uniformly decreasing the availability of public transport services, promoting sus...
El acceso a la información espacial y las nuevas tecnologías geográficas, 2006, ISBN 84-338-3944-6, págs. 1809-1819, 2006
Contextos universitarios tranformadores: Boas prácticas no marco dos GID., 2020, ISBN 978-84-9749-775-6, págs. 553-556, 2020
Proceedings of the 39th IAHR World Congress, 2022
Durante la última década la Encuesta sobre Infraestructura y Equipamientos Locales (EIEL) ha inic... more Durante la última década la Encuesta sobre Infraestructura y Equipamientos Locales (EIEL) ha iniciado el camino hacia consolidarse como uno de los proyectos de referencia en cualquier trabajo que incluya información geográfica en ámbitos municipales. La EIEL ...
Las capacidades para la gestión, procesado y análisis de datos geoespaciales que ofrecen los Sist... more Las capacidades para la gestión, procesado y análisis de datos geoespaciales que ofrecen los Sistemas de Información Geográfica unidas a las prestaciones de visualización de los navegadores 3D sobre el terreno, abre una cantidad ilimitada de posibilidades en el área de la cartografía digital y su explotación en diferentes ámbitos técnicos y sociales.(...)
videalab.udc.es
RESUMEN: Tras la experiencia de los últimos años en el desarrollo del Sistema Avanzado de Navegac... more RESUMEN: Tras la experiencia de los últimos años en el desarrollo del Sistema Avanzado de Navegación en Terrenos Interactivos (SANTI), es decir, un sistema interactivo de visualización tridimensional de terreno en tiempo real basado en datos altimétricos e imágenes de satélite y aéreas, se abre una nueva línea de investigación que integra esta visualización con sistemas de información geográfica (SIG o Geographic Information System GIS en inglés). Esta nueva línea de desarrollo ofrece grandes posibilidades para ...
Case Studies on Transport Policy
Highlights • Local population density is a dominant factor in LRT performance contrasts. • Bus-LR... more Highlights • Local population density is a dominant factor in LRT performance contrasts. • Bus-LRT connectivity and LRT service level follow as top-tier performance factors. • Regional city planning and urban design traditions influence performance outcomes. • Multifactor heuristics can effectively and fairly rank LRT systems on 14 measures. • Spanish LRT cases markedly outperform North American cases in this study.
Emapic e un proxecto asociado ao Laboratorio CartoLab da Universidade da Coruna que permite xesti... more Emapic e un proxecto asociado ao Laboratorio CartoLab da Universidade da Coruna que permite xestionar informacion ou opinion distribuida sobre un mapa, de forma sinxela e inmediata. As suas funcionalidades van mais ala dunha ferramenta en codigo aberto para a creacion de enquisas online, pois e unha aplicacion de representacion cartografica de datos xerados en procesos colaborativos de participacion cidada. Calquera tipo de dato facilitado por participantes via navegadores web ou mobil pode ser rexistrado para ser de utilidade en calquera ambito de analise, investigacion e xestion urbana ou territorial.
Water, 2020
This article presents a novel installation for the development of hybrid physical-numerical flood... more This article presents a novel installation for the development of hybrid physical-numerical flood models in an augmented reality environment. This installation extends the concept introduced by the well-known Augmented Reality-SandBox (AR-Sandbox) module, which presents a more educational, and less research-based and professional application. It consists of a physical scale topography built in a sandbox into which other elements (such as buildings, roads or dikes) can be incorporated. A scanner generates, in real time, a Digital Terrain Model (DTM) from the sandbox topography, which serves as a basis for the simulation of overland flow using professional hydraulic software (Iber+). The hydraulic and hydrological parameters (surface roughness, inlet discharges, boundary conditions) are entered with a simple Graphical User Interface (GUI) developed specifically for this project, as indeed was the entire system that allows the visualization of the simulation results. This allows us to ...
Networks and Spatial Economics, 2020
Residential location choice (RLC) predicts where and how people choose their residential location... more Residential location choice (RLC) predicts where and how people choose their residential location in the framework of land use-transport interaction models (LUTI). This paper seeks an efficient RLC model in the context of irregular zoning of location alternatives. The main current proposals in the field are discrete choice models. In RLC modeling, the alternatives are spatial units, and spatially correlated logit (SCL) is an efficient approach when the analyst cannot pre-define groups of alternatives that efficiently reflect the systematic substitution patterns among the alternatives. The SCL uses the spatial information on the contiguity of the zones to determine spatial correlation among the alternatives. Urban residential location choice usually uses administrative zoning, which is very irregular in many cities (mainly historic cities); however, SCL is not efficient in this context owing to the limitations of the binary contiguity spatial variable employed as a spatial correlation metric (SCM). This paper proposes an extension of the mixed SCL model, with an SCM based on the proportion of common border length in contiguous zones, which is more efficient in the irregular urban zoning context. The proposed model is applied to an urban case study of LUTI RLC modeling with irregular zoning, based on the administrative divisions of the city of Santander (Spain) and is shown to be empirically more efficient than the previous approaches.
… de tecnología para el …, 2009
* Las opiniones que se expresan en la presente entrevista son estrictamente de su autor y no resp... more * Las opiniones que se expresan en la presente entrevista son estrictamente de su autor y no responden en ningún caso al departamento de las Naciones Unidas al que pertenece. Director del Centro de Geoinformación de la United Nations Logistic Base (UNLB) en Bríndisi (Italia) "No utilizamos software libre. […] desde un punto de vista práctico nosotros tenemos que producir; no podemos jugar con las vidas humanas" títol article autor 2 [cuadernosinternacionales] de tecnología para el desarrollo humano febrero 2009 tecnologías de la información geográfica Francisco José Igualada Delgado obtuvo, en 1981, la licenciatura en Geología de la Universidad de Barcelona. Trabajó en Dames & Moore Ingenieros en Teruel y Madrid, y en 1983 se incorporó al South African Department of Economic Affairs (Servicios Geológicos de Sudáfrica) en Mafeking, en proyectos de geotecnia, geofísica y minería; posteriormente, en España trabajo por un corto tiempo en el ITGME. En 1986 cursó un diploma de posgrado-máster en Ingeniería Geológica y Teledetección, en el ITC, Universidad de Utrecht Enschede (Holanda). En 1987 fue responsable, en TRABAJOS CATAS-TRALES S.A. Pamplona, de teledetección y sistemas de información para estadísticas agrarias, medioambiente, cartografía y fotogrametría, participando en proyectos europeos, como MARS y Corine. A finales de 1989, en AURENSA (Madrid), fue jefe de proyectos multidisciplinares internacionales de geoinformación, ingeniería y medioambiente con satélites de observación de la Tierra y Sistemas de Información Geográficos (SIG). En 1993 completó un programa de investigación doctoral en Cranfield University, Silsoe (Reino Unido) iniciado años antes, obteniendo "M.Phil/PhD Information Systems (GIS-geomatics)" a través de un proyecto de la Comisión Europea (JRC). En agosto de 1993, empezó en el European Union Satellite Centre (EUSC) con base en Madrid y Bruselas. Durante los casi 9 años que estuvo en esta organización, utilizó todo tipo de imágenes ópticas y de radar, enfocándose hacia la gestión de crisis y temas de seguridad internacional. Fue manager de proyectos de SIG, seguridad medioambiental y analista senior de IMINT; al mismo tiempo que corresponsable de la explotación del satélite Helios en diversas crisis regionales. Paralelamente, en el año 2000 obtuvo un MBA "International Executive" por ESCP-EAP Business School de Madrid. Durante los años 2002-03, trabajó en el
La recogida masiva de información sobre carreteras usando diversas tecnologías (GPS, fotografías,... more La recogida masiva de información sobre carreteras usando diversas tecnologías (GPS, fotografías, gravitógrafo, etc.) genera gran cantidad de datos que no siempre se consigue aprovechar debidamente. El CATVIS es un catálogo visual de carreteras con datos puntuales cada 10 metros almacenados en una compleja y extensa base de datos alfanumérica.
Remote Sensing
The point clouds acquired with a mobile LiDAR scanner (MLS) have high density and accuracy, which... more The point clouds acquired with a mobile LiDAR scanner (MLS) have high density and accuracy, which allows one to identify different elements of the road in them, as can be found in many scientific references, especially in the last decade. This study presents a methodology to characterize the urban space available for walking, by segmenting point clouds from data acquired with MLS and automatically generating impedance surfaces to be used in pedestrian accessibility studies. Common problems in the automatic segmentation of the LiDAR point cloud were corrected, achieving a very accurate segmentation of the points belonging to the ground. In addition, problems caused by occlusions caused mainly by parked vehicles and that prevent the availability of LiDAR points in spaces normally intended for pedestrian circulation, such as sidewalks, were solved in the proposed methodology. The innovation of this method lies, therefore, in the high definition of the generated 3D model of the pedestri...
ISPRS International Journal of Geo-Information, 2019
Naturalistic driving can generate huge datasets with great potential for research. However, to an... more Naturalistic driving can generate huge datasets with great potential for research. However, to analyze the collected data in naturalistic driving trials is quite complex and difficult, especially if we consider that these studies are commonly conducted by research groups with somewhat limited resources. It is quite common that these studies implement strategies for thinning and/or reducing the data volumes that have been initially collected. Thus, and unfortunately, the great potential of these datasets is significantly constrained to specific situations, events, and contexts. For this, to implement appropriate strategies for the visualization of these data is becoming increasingly necessary, at any scale. Mapping naturalistic driving data with Geographic Information Systems (GIS) allows for a deeper understanding of our driving behavior, achieving a smarter and broader perspective of the whole datasets. GIS mapping allows for many of the existing drawbacks of the traditional method...
ISPRS international journal of geo-information, Dec 29, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Computer-Aided Civil and Infrastructure Engineering
Sustainability
This study aimed to investigate the relationship between the characteristics of the areas of infl... more This study aimed to investigate the relationship between the characteristics of the areas of influence of bus stops and the decrease in ridership during COVID-19 lockdowns and subsequent initial reopening processes. A novel GIS methodology was developed to determine these characteristics from a large amount of data with high spatial detail and accurately assign them to individual bus stops. After processing the data, several multiple linear regression models were developed to determine the variables related to different activities and changes in mobility during lockdown that may explain the variation in demand owing to the COVID-19 pandemic. The characteristics related to population and land use were also studied. The proposed methodology can be used to improve transit planning during exceptional situations, by strengthening public transport in areas with a predictably higher transit demand, instead of uniformly decreasing the availability of public transport services, promoting sus...
El acceso a la información espacial y las nuevas tecnologías geográficas, 2006, ISBN 84-338-3944-6, págs. 1809-1819, 2006
Contextos universitarios tranformadores: Boas prácticas no marco dos GID., 2020, ISBN 978-84-9749-775-6, págs. 553-556, 2020
Proceedings of the 39th IAHR World Congress, 2022
Durante la última década la Encuesta sobre Infraestructura y Equipamientos Locales (EIEL) ha inic... more Durante la última década la Encuesta sobre Infraestructura y Equipamientos Locales (EIEL) ha iniciado el camino hacia consolidarse como uno de los proyectos de referencia en cualquier trabajo que incluya información geográfica en ámbitos municipales. La EIEL ...
Las capacidades para la gestión, procesado y análisis de datos geoespaciales que ofrecen los Sist... more Las capacidades para la gestión, procesado y análisis de datos geoespaciales que ofrecen los Sistemas de Información Geográfica unidas a las prestaciones de visualización de los navegadores 3D sobre el terreno, abre una cantidad ilimitada de posibilidades en el área de la cartografía digital y su explotación en diferentes ámbitos técnicos y sociales.(...)
videalab.udc.es
RESUMEN: Tras la experiencia de los últimos años en el desarrollo del Sistema Avanzado de Navegac... more RESUMEN: Tras la experiencia de los últimos años en el desarrollo del Sistema Avanzado de Navegación en Terrenos Interactivos (SANTI), es decir, un sistema interactivo de visualización tridimensional de terreno en tiempo real basado en datos altimétricos e imágenes de satélite y aéreas, se abre una nueva línea de investigación que integra esta visualización con sistemas de información geográfica (SIG o Geographic Information System GIS en inglés). Esta nueva línea de desarrollo ofrece grandes posibilidades para ...
Case Studies on Transport Policy
Highlights • Local population density is a dominant factor in LRT performance contrasts. • Bus-LR... more Highlights • Local population density is a dominant factor in LRT performance contrasts. • Bus-LRT connectivity and LRT service level follow as top-tier performance factors. • Regional city planning and urban design traditions influence performance outcomes. • Multifactor heuristics can effectively and fairly rank LRT systems on 14 measures. • Spanish LRT cases markedly outperform North American cases in this study.
Emapic e un proxecto asociado ao Laboratorio CartoLab da Universidade da Coruna que permite xesti... more Emapic e un proxecto asociado ao Laboratorio CartoLab da Universidade da Coruna que permite xestionar informacion ou opinion distribuida sobre un mapa, de forma sinxela e inmediata. As suas funcionalidades van mais ala dunha ferramenta en codigo aberto para a creacion de enquisas online, pois e unha aplicacion de representacion cartografica de datos xerados en procesos colaborativos de participacion cidada. Calquera tipo de dato facilitado por participantes via navegadores web ou mobil pode ser rexistrado para ser de utilidade en calquera ambito de analise, investigacion e xestion urbana ou territorial.
Water, 2020
This article presents a novel installation for the development of hybrid physical-numerical flood... more This article presents a novel installation for the development of hybrid physical-numerical flood models in an augmented reality environment. This installation extends the concept introduced by the well-known Augmented Reality-SandBox (AR-Sandbox) module, which presents a more educational, and less research-based and professional application. It consists of a physical scale topography built in a sandbox into which other elements (such as buildings, roads or dikes) can be incorporated. A scanner generates, in real time, a Digital Terrain Model (DTM) from the sandbox topography, which serves as a basis for the simulation of overland flow using professional hydraulic software (Iber+). The hydraulic and hydrological parameters (surface roughness, inlet discharges, boundary conditions) are entered with a simple Graphical User Interface (GUI) developed specifically for this project, as indeed was the entire system that allows the visualization of the simulation results. This allows us to ...
Networks and Spatial Economics, 2020
Residential location choice (RLC) predicts where and how people choose their residential location... more Residential location choice (RLC) predicts where and how people choose their residential location in the framework of land use-transport interaction models (LUTI). This paper seeks an efficient RLC model in the context of irregular zoning of location alternatives. The main current proposals in the field are discrete choice models. In RLC modeling, the alternatives are spatial units, and spatially correlated logit (SCL) is an efficient approach when the analyst cannot pre-define groups of alternatives that efficiently reflect the systematic substitution patterns among the alternatives. The SCL uses the spatial information on the contiguity of the zones to determine spatial correlation among the alternatives. Urban residential location choice usually uses administrative zoning, which is very irregular in many cities (mainly historic cities); however, SCL is not efficient in this context owing to the limitations of the binary contiguity spatial variable employed as a spatial correlation metric (SCM). This paper proposes an extension of the mixed SCL model, with an SCM based on the proportion of common border length in contiguous zones, which is more efficient in the irregular urban zoning context. The proposed model is applied to an urban case study of LUTI RLC modeling with irregular zoning, based on the administrative divisions of the city of Santander (Spain) and is shown to be empirically more efficient than the previous approaches.
… de tecnología para el …, 2009
* Las opiniones que se expresan en la presente entrevista son estrictamente de su autor y no resp... more * Las opiniones que se expresan en la presente entrevista son estrictamente de su autor y no responden en ningún caso al departamento de las Naciones Unidas al que pertenece. Director del Centro de Geoinformación de la United Nations Logistic Base (UNLB) en Bríndisi (Italia) "No utilizamos software libre. […] desde un punto de vista práctico nosotros tenemos que producir; no podemos jugar con las vidas humanas" títol article autor 2 [cuadernosinternacionales] de tecnología para el desarrollo humano febrero 2009 tecnologías de la información geográfica Francisco José Igualada Delgado obtuvo, en 1981, la licenciatura en Geología de la Universidad de Barcelona. Trabajó en Dames & Moore Ingenieros en Teruel y Madrid, y en 1983 se incorporó al South African Department of Economic Affairs (Servicios Geológicos de Sudáfrica) en Mafeking, en proyectos de geotecnia, geofísica y minería; posteriormente, en España trabajo por un corto tiempo en el ITGME. En 1986 cursó un diploma de posgrado-máster en Ingeniería Geológica y Teledetección, en el ITC, Universidad de Utrecht Enschede (Holanda). En 1987 fue responsable, en TRABAJOS CATAS-TRALES S.A. Pamplona, de teledetección y sistemas de información para estadísticas agrarias, medioambiente, cartografía y fotogrametría, participando en proyectos europeos, como MARS y Corine. A finales de 1989, en AURENSA (Madrid), fue jefe de proyectos multidisciplinares internacionales de geoinformación, ingeniería y medioambiente con satélites de observación de la Tierra y Sistemas de Información Geográficos (SIG). En 1993 completó un programa de investigación doctoral en Cranfield University, Silsoe (Reino Unido) iniciado años antes, obteniendo "M.Phil/PhD Information Systems (GIS-geomatics)" a través de un proyecto de la Comisión Europea (JRC). En agosto de 1993, empezó en el European Union Satellite Centre (EUSC) con base en Madrid y Bruselas. Durante los casi 9 años que estuvo en esta organización, utilizó todo tipo de imágenes ópticas y de radar, enfocándose hacia la gestión de crisis y temas de seguridad internacional. Fue manager de proyectos de SIG, seguridad medioambiental y analista senior de IMINT; al mismo tiempo que corresponsable de la explotación del satélite Helios en diversas crisis regionales. Paralelamente, en el año 2000 obtuvo un MBA "International Executive" por ESCP-EAP Business School de Madrid. Durante los años 2002-03, trabajó en el
La recogida masiva de información sobre carreteras usando diversas tecnologías (GPS, fotografías,... more La recogida masiva de información sobre carreteras usando diversas tecnologías (GPS, fotografías, gravitógrafo, etc.) genera gran cantidad de datos que no siempre se consigue aprovechar debidamente. El CATVIS es un catálogo visual de carreteras con datos puntuales cada 10 metros almacenados en una compleja y extensa base de datos alfanumérica.
Remote Sensing
The point clouds acquired with a mobile LiDAR scanner (MLS) have high density and accuracy, which... more The point clouds acquired with a mobile LiDAR scanner (MLS) have high density and accuracy, which allows one to identify different elements of the road in them, as can be found in many scientific references, especially in the last decade. This study presents a methodology to characterize the urban space available for walking, by segmenting point clouds from data acquired with MLS and automatically generating impedance surfaces to be used in pedestrian accessibility studies. Common problems in the automatic segmentation of the LiDAR point cloud were corrected, achieving a very accurate segmentation of the points belonging to the ground. In addition, problems caused by occlusions caused mainly by parked vehicles and that prevent the availability of LiDAR points in spaces normally intended for pedestrian circulation, such as sidewalks, were solved in the proposed methodology. The innovation of this method lies, therefore, in the high definition of the generated 3D model of the pedestri...