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[EN] The main objective of this paper is to contribute to the knowledge of the topography of the city of Cartagena in the early Roman Empire times. A Geographic Information System has been used with data from numerous archaeological excavations, available historic maps and new GPS observations referred to landmarks of that era that are currently on the soil surface. Some meaningful results are: the compilation of spatial information from different sources in a single database, the creation of thematic maps and the generation and analysis of digital elevation models based on these data, which were compared with the contemporary ones. Some notable conclusions are the generation of a methodological model, the contribution to systematic knowledge of the historical topography of Cartagena and the interest of expanding the area of study and considering other periods, [ES] El principal objetivo de este trabajo es contribuir al conocimiento de la topografía de la ciudad de Cartagena en la época romana altoimperial. Se ha empleado un Sistema de Información Geográfica y datos procedentes de numerosas excavaciones arqueológicas, de la cartografía histórica disponible y de observaciones GPS realizadas ex profeso y referidas a puntos característicos de aquella época que están actualmente en superficie. Entre los resultados obtenidos están la recopilación de información espacial procedente de diversas fuentes en una base de datos, la creación de cartografía temática y la generación y análisis de modelos digitales de elevaciones basados en esos datos y que se han comparado con el de la época actual. Entre las conclusiones cabe destacar la creación de un modelo metodológico, la aportación al conocimiento sistemático de la topografía histórica de Cartagena y el interés de ampliar la zona de estudio y de considerar también otras épocas, El presente trabajo se enmarca dentro del proyecto de investigación “Carthago Nova: Topografía y urbanística de una urbe Mediterránea privilegiada” [HAR2011.29330] del Ministerio de Economía y Competitividad, financiado con Fondos FEDER.

Sometimes when connecting a crest vertical curve, followed by a sag and another crest, a road disappears from the view of a driver to reappear later. Then, there is a loss of path or a hidden dip in a road. It is essential to avoid losses when they hide dangerous points, such as intersections or unexpected changes in direction. In addition, this loss disrupts drivers and its effect depends on quantitative relationships between the variables involved in the problem. This paper presents a quantitative procedure for studying hidden dips in roads. The method is based on calculating the sections visible and hidden by a driver using a Geographic Information System. An application to a Spanish road is presented. Procedure results were compared with in situ carried out studies and with a video of the highway recorded using a Global Positioning System equipped video camera embarked in a vehicle. The main quantitative issues related to hidden dips are discussed.

"Special issue : Intelligent multisensory systems in support of information society", The society is changing towards a new paradigm in which an increasing number of old adults live alone. In parallel, the incidence of conditions that affect mobility and independence is also rising as a consequence of a longer life expectancy. In this paper, the specific problem of falls of old adults is addressed by devising a technological solution for monitoring these users. Video cameras, accelerometers and GPS sensors are combined in a multi-modal approach to monitor humans inside and outside the domestic environment. Machine learning techniques are used to detect falls and classify activities from accelerometer data. Video feeds and GPS are used to provide location inside and outside the domestic environment. It results in a monitoring solution that does not imply the confinement of the users to a closed environment., This work is funded by National Funds through the FCT-Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project PEst- OE/EEI/UI0752/2011. The work of Davide Carneiro is also supported by a doctoral grant by FCT (SFRH/BD/64890/2009). This work is also partially supported by the Spanish Ministerio de Economía y Competitividad / FEDER under project TIN2010-20845-C03-01.

En esta memoria se presentan dos métodos iterativos de órdenes cuatro y cinco, respectivamente, para resolver sistemas no lineales de ecuaciones. Realizamos comparaciones numéricas con otros métodos existente de órdenes dos (Newton), tres (Traub) y cuatro (Sharma) con aplicación al sistema no lineal de ecuaciones del Global Positioning System (GPS) y otros sistemas no lineales académicos., In this paper, two iterative methods, of order four and five, respectively, are presented for solving nonlinear systems of equations. Numerical comparisons are made with other existing second (Newton) and fourth-order (Sharma) schemes to solve the nonlinear system of equations of the Global Positioning System (GPS) and some academic nonlinear systems.

More than 50% of injury accidents in Spain take place on crosstown roads in urban areas. Traffic calming is an initiative to reduce the impact of traffic on local streets by lowering both the number and the severity of crashes. However, the implementation of traffic-calming devices in Spain was not standardized in the past, and no technical criteria were applied. The paper presents the methodology, results, and conclusions of an analysis specifically related to speed tables, which are flat-topped speed humps, as part of the research project MODETRA. For the research, five low-volume crosstown roads with 16 speed tables were selected to analyze drivers' behavior. Speed data were collected from a sample of more than 900 vehicles through the selected crosstown roads using Global Positioning System trackers. For each individual vehicle, a continuous speed profile along the path was obtained. The analysis showed that the minimum speed occurred when the vehicle left the traffic-calming device and the maximum deceleration occurred just before the device. Geometric characteristics of the speed tables were measured by using a digital profilometer. A wide dispersion in the geometry can be concluded. It was found that the speed reduction depended mainly on the separation between traffic-calming devices, whereas the speed over the speed tables depended crucially on the entrance-ramp slope, the speed table length, and the distance from the previous traffic control device. Also, no statistical correlations were found between speed table height and speed reduction or spot speed over the speed table., The authors thank the Center for Studies and Experimentation of Public Works of the Spanish Ministry of Public Works, which subsidized the research. They also thank the Infrastructure and Transportation Department, General Directorate of Public Works, Valencian Government, Spain, and the Ministry of the Interior, General Directorate of Traffic, Spain, for their cooperation during data collection.

[ES] Uno de los objetivos más importantes de los Sistemas Inteligentes de Transporte (ITS) es evitar la pérdida de precisión en el posicionamiento y guiado del vehículo, debido a la disminución en la calidad de la señal del Sistema de Posicionamiento Global (GPS). En este artículo, se presenta un sistema de posicionamiento formado por la combinación de un GPS con una unidad de medida inercial ayudada por los sensores embarcados en el coche para realizar el guiado. En función de la precisión proporcionada por el GPS, el sistema discrimina entre tres posibles comportamientos: 1) Si la precisión es centimétrica, el GPS se encarga en solitario del guiado. 2) Si no se recibe la señal GPS, el control lo toma la unidad inercial. 3) Si la precisión de la señal del GPS no es centimétrica, la posición del vehículo se calcula mediante una combinación de ambas medidas. El sistema se ha instalado en un Citroën C3 Pluriel. Los resultados muestran un correcto comportamiento del vehículo en diferentes situaciones y prueban la necesidad de integrar la información sensorial para realizar un control de navegación óptimo., [EN] Loss of accuracy in automated vehicle position control systems due to Global Positioning System (GPS) signal quality is currently one of the most studied research topics in the field of Intelligent Transportation Systems (ITS). This paper presents an integrated positioning system that combines a GPS with onboard sensors and an Inertial Measurement Unit (IMU) to perform autonomous vehicle guidance. Depending on GPS precision, the system discriminates which positioning is most appropriate from three different possibilities: 1) real-time kinematic differential global positioning system (RTK-DGPS) is working at the highest positioning accuracy (1 cm). In this instance, GPS data are used as the main sensory supply; 2) total DGPS signal loss. Now, the IMU control system takes control; 3) centimeter accuracy is lost. In this instance, GPS and IMU measurements are integrated to determine the true positioning. This system has been installed in a Citroën C3 Pluriel car, where all the actuators were automated to achieve human-like driving. Experimental results show the car's behavior in diverse situations and prove that the test-bed vehicle can maintain automatic navigation even when GPS positioning is unavailable. The results also show the need to combine sensory information to obtain optimum navigation control in any circumstance., Este trabajo ha sido realizado gracias al apoyo de los proyectos CyberCars-2 (UE STREP FP6-028062), ENVITE (Ministerio de Fomento, T7 / 06) y MARTA (CDTI, CENIT 2007).

A system including Global Positioning Systems (GPS) and digital cartography is a good solution to carry out vehicle's guidance. However, it has inconveniences like high sensibility to multipath and interference when the GPS signal is blocked by external agents. Another system is mandatory to avoid this error. This paper presents a cooperative system based on GPS and Inertial Navigation Systems (INS) for automated vehicle position. The control system includes a decision unit to choose which value is the correct. In case GPS is working at top precision, it takes the control. On the other part, GPS signal can be lost and inertial control system guides the car in this occasion. A third possibility is contemplated: we receive the signal from GPS but the accuracy is over one meter. Now, position value is obtained by means of both systems. Experimental results analyze two situations: guidance in an urban area where GPS signal can be occluded by buildings or trees during short time intervals and the possibility of loss of the signal in long time to simulate the circulation in tunnels. Good results have been observed in tests and it demonstrates how a cooperative system improves the automated vehicle guidance., This work was carried out with the support of projects ISAAC2-SARA (CICYTDPI2005-0798-C03-C01), ENVITE (Ministerio de Fomento T7/06) and CSIC 13P program, co funded by the European Social Fund

PERDIGUER, R. "Estrategias de cálculo del retardo troposférico y su influencia en procesamiento GPS de alta precisión". En: 6ª Asamblea Hispano Portuguesa de Geodesia e Geofísica, (Tomar, 11-14 de febrero de 2008), Zenith Tropospheric Delay (ZTD) computation is a major task in GPS observation treatment. Usual/y, ZTDs are obtained trough existing models like Saastamoinen (1973) or Hopfield (1969). The meteorological data involved to compute these models can be obtained from empirical global models, like SA (Standard Atmosphere), "Minimum Operational Performance Standards" (MOPS) or GTP (Global Pressure and Temperature). These models are improved by mappingfunction like Niel! (1996) or Herring (1996). Nevertheless, the best option should be obtained with the local/y registered meteorological data. 1n this paper, different models and meteorological parameters are compared in order to establish maximum difference criteria between the values obtained by the Global models and the local measured ones. For such purposes, two lGS wel/-known station with meteorological sensor have been used: MATEra and Z1MMerwald. For the GPS data ana/ysis, Bernese 5.0 and AutoGNS (Zurutuza et al., 2007) have been used.

GÁRATE, J. "Despliegue de estaciones GPS permanentes en el marco del proyecto Topo-Iberia". En: 6ª Asamblea Hispano Portuguesa de Geodesia e Geofísica, (Tomar, 11-14 de febrero de 2008), Topo-Iberia is the short name of a Spanish Research Council funded project. lts main objective is to understand interactions among deep, shallow and atmospheric processes, integrating geological, geophysical, geodetic and geotechnological researching activities. Knowledge of topographic changes and their causes are needed in order to assess natural hazards. It is also important to take them into account when evaluating the climatic change impact. The project will be focused in three main areas of interest, located in the Iberian Peninsula: Northern and Southern borders of the lberian micro-plate, as well as its central core. However, the Southern border does not imply that the Northern Moroccan behaviour is not taken into account. This paper will show the preliminary steps that the Topo-Iberia GPS working group is undergoing in order lo deploy a new Continuous GPS Network at Spain and Morocco. We are trying to complement the airead y existing and functioning CGPS Networks (e.g. ROA, ERGPS) by increasing the spatial coverage across Spain and Northern Morocco. While the purchasing procedures have beenfollowed, the places for the new locations have been chosen. A set of available CGPS data files has been downloaded from different institutional servers. A preliminary data analysis has been performed as a maller of geodetic quality control. Since some of the existing CGPS stations have been installed without fol/owing strict lGS/EUREF procedures for the stability of the monumenls, we are investigating their performance through the time series analysis, in order to decide whether to include them as complementing stations to the Topo-Iberia network.

Comunicación presntada a la 3ª Asamblea Hispano-Portuguesa de Geodesia y Geofísica = 3ª Assembleia Luso-Espanhola de Geodesia e Geofisica, celebrada en Valencia entre el 4 y el 8 de febrero de 2002., The Institute of Astronomy and Geodesy (UCM-CSIC) has installed a GPS permanent station in the geodynamic complex of Jameos in Lanzarote. In this same place there are two automated tide gauges of precision (pressure sensors). With these instruments it is sought to study the sea level variations and their possible correlation with the GPS observations. For these studies it is absolutely necessary to have an altimetric link with high accuracy between the reference point of the pillar where the GPS antenna is installed and the tide gauges bench marks. We have carried out two observation campaigns in the years 2000 and 2001. Methods of repeated geometric levelling of very short tracts have been used due to the great existent level difference. The reciprocal and simultaneous trigonometric levelling has also been used that is adapted in this type of visual inclined. In this paper the works carried out in the two epochs with the putpose of making the altimetric connections before mentioned are described. The results obtained, the evaluation of the levelling campaigns, and the comparison of the levels of different measurements are also presented.

The adoption of GPS technology in Archaeology is relatively recent and its use is increasing more and more. The excellent results obtained from the mapping of archaeological elements has led many archaeologists to acquire GPS systems, professional in some cases and pocket in other. This paper tries to introduce this technology, showing its possibilities and more frequent uses in archaeology. This contribution also tries to give a critical vision in the application of the different kind of receivers and the ways of professional use., La incorporación de la tecnología GPS a la arqueología es relativamente reciente y su uso cada vez mayor. Los excelentes resultados obtenidos en la georreferenciación de elementos arqueológicos han movido a muchos profesionales a la adquisición de equipos, unas veces profesionales y otras de bolsillo. Este trabajo pretende servir de presentación de esta tecnología exponiendo sus posibilidades y usos más frecuentes en arqueología, además de hacer una serie de puntualizaciones en cuanto a la fiabilidad, precisión de los diferentes tipos de receptores portátiles y formas de aplicación con carácter profesional de estos equipos.