Departament d'Infraestructura del Transport i el Territori (fins octubre 2015)http://hdl.handle.net/2117/18022024-03-29T15:50:56Z2024-03-29T15:50:56ZSuppression of spurious frequencies in scattering problems by means of boundary algebraic and combined field equationsPoblet-Puig, JordiValyaev, ValeryShanin, Andreyhttp://hdl.handle.net/2117/769962020-07-23T20:52:34Z2015-09-21T14:54:27ZSuppression of spurious frequencies in scattering problems by means of boundary algebraic and combined field equations
Poblet-Puig, Jordi; Valyaev, Valery; Shanin, Andrey
A numerical technique for solving scattering problems is presented. It is
based on a boundary integral equation idea, so the unknowns are localized on the contour (in 2D case) or the surface (in 3D case) of the scattering object. Two major difficulties of traditional boundary integral methods (the appearance of spurious resonances and the necessity to perform numerical integration of singular functions) are overcome by studying the problem in an approximate discrete formulation from the very beginning. The space is filled by cubic blocks, and the shape of the scatterer is formed by a set of blocks removed from the space. Thus, the formulation of the problem is discrete and the continuous Green’s function is substituted by a discrete mesh Green’s function. An analogue of combined field boundary integral equation (CFIE) is developed for this formulation.
2015-09-21T14:54:27ZPoblet-Puig, JordiValyaev, ValeryShanin, AndreyA numerical technique for solving scattering problems is presented. It is
based on a boundary integral equation idea, so the unknowns are localized on the contour (in 2D case) or the surface (in 3D case) of the scattering object. Two major difficulties of traditional boundary integral methods (the appearance of spurious resonances and the necessity to perform numerical integration of singular functions) are overcome by studying the problem in an approximate discrete formulation from the very beginning. The space is filled by cubic blocks, and the shape of the scatterer is formed by a set of blocks removed from the space. Thus, the formulation of the problem is discrete and the continuous Green’s function is substituted by a discrete mesh Green’s function. An analogue of combined field boundary integral equation (CFIE) is developed for this formulation.Agent based modeling for simulating taxi services[: case study in Barcelona]Salanova Grau, Josep MariaEstrada Romeu, Miguel Ángelhttp://hdl.handle.net/2117/767202020-07-23T21:51:43Z2015-09-09T15:32:49ZAgent based modeling for simulating taxi services[: case study in Barcelona]
Salanova Grau, Josep Maria; Estrada Romeu, Miguel Ángel
Taxi services account for a significant part of the daily trips in most of cities around the world. Due to the fact that most of the taxi markets are regulated by a central authority there is the need for developing tools for understanding the behavior of these markets to policy regulations and supporting decision makers. This paper presents an agent based model for simulating taxi services in urban areas. Taxi models presented in the literature can be grouped into aggregated, equilibrium and simulation models, with the latter having been studied to a lesser extent. Agent simulation is a powerful tool for analyzing such complex problems, where stochastic nature of the variables and spatial distribution hinders the application of aggregated models. The agent-based model is presented together with the behavioral rules of the agents and applied to the city of Barcelona, obtaining the optimum number of vehicles and performance indicators of the provision of taxi services under the dispatching operation mode.
2015-09-09T15:32:49ZSalanova Grau, Josep MariaEstrada Romeu, Miguel ÁngelTaxi services account for a significant part of the daily trips in most of cities around the world. Due to the fact that most of the taxi markets are regulated by a central authority there is the need for developing tools for understanding the behavior of these markets to policy regulations and supporting decision makers. This paper presents an agent based model for simulating taxi services in urban areas. Taxi models presented in the literature can be grouped into aggregated, equilibrium and simulation models, with the latter having been studied to a lesser extent. Agent simulation is a powerful tool for analyzing such complex problems, where stochastic nature of the variables and spatial distribution hinders the application of aggregated models. The agent-based model is presented together with the behavioral rules of the agents and applied to the city of Barcelona, obtaining the optimum number of vehicles and performance indicators of the provision of taxi services under the dispatching operation mode.Aggregated modeling of urban taxi servicesSalanova Grau, Josep MariaEstrada Romeu, Miguel ÁngelAmat Bertran, Carleshttp://hdl.handle.net/2117/766912020-07-23T23:16:28Z2015-09-08T15:08:53ZAggregated modeling of urban taxi services
Salanova Grau, Josep Maria; Estrada Romeu, Miguel Ángel; Amat Bertran, Carles
Various models have been developed for calculating the variables that characterize the taxi services in urban regions and defining the principal policy measures such as fleet size, fares or available operational modes. This paper presents an extensive review of the presented formulations for the modeling of taxi services in urban areas. The variables of the problem are identified and analyzed, presenting the different formulations proposed in the literature for each one of the three operational modes (hailing, stand and dispatching). The paper also presents an aggregated mathematical model for the estimation of the key performance indicators of taxi markets in urban areas taking into account demand elasticity. These key parameters are basically the demand and supply for taxi services, the waiting time of taxi users and the cost of the involved actors, i. e. the customers and the drivers. A generalized cost function is proposed and applied to the dispatching taxi services market, obtaining results in terms of demand, system unitary costs, waiting time and drivers’ benefit for different combinations of supply and fares. It is concluded that demand is more sensitive to waiting time than to cost for high waiting times, but when the waiting time is low, the cost is the most significant factor of the demand.
2015-09-08T15:08:53ZSalanova Grau, Josep MariaEstrada Romeu, Miguel ÁngelAmat Bertran, CarlesVarious models have been developed for calculating the variables that characterize the taxi services in urban regions and defining the principal policy measures such as fleet size, fares or available operational modes. This paper presents an extensive review of the presented formulations for the modeling of taxi services in urban areas. The variables of the problem are identified and analyzed, presenting the different formulations proposed in the literature for each one of the three operational modes (hailing, stand and dispatching). The paper also presents an aggregated mathematical model for the estimation of the key performance indicators of taxi markets in urban areas taking into account demand elasticity. These key parameters are basically the demand and supply for taxi services, the waiting time of taxi users and the cost of the involved actors, i. e. the customers and the drivers. A generalized cost function is proposed and applied to the dispatching taxi services market, obtaining results in terms of demand, system unitary costs, waiting time and drivers’ benefit for different combinations of supply and fares. It is concluded that demand is more sensitive to waiting time than to cost for high waiting times, but when the waiting time is low, the cost is the most significant factor of the demand.Evaluation of the GPR frequency spectra in asphalt pavement assessmentPedret Rodés, JosepPérez Gracia, María de la VegaMartínez Reguero, Adriana Haydéehttp://hdl.handle.net/2117/765242022-09-11T01:08:39Z2015-08-26T11:49:36ZEvaluation of the GPR frequency spectra in asphalt pavement assessment
Pedret Rodés, Josep; Pérez Gracia, María de la Vega; Martínez Reguero, Adriana Haydée
Ground penetrating radar (GPR) is frequently used in pavement assessments, mainly using the evaluation of wave travel times. However, GPR data provide further information that could be used in order to determine the inner conditions and characteristics about materials. In this paper, the possible analysis of the frequency spectrum of GPR signals is analysed and discussed. Several tests were carried out in a portion of a highway in two different stages of its service life. Results highlight the relationship between the shape of the spectrum and the frequency signature with the structure and conditions of the pavement.
2015-08-26T11:49:36ZPedret Rodés, JosepPérez Gracia, María de la VegaMartínez Reguero, Adriana HaydéeGround penetrating radar (GPR) is frequently used in pavement assessments, mainly using the evaluation of wave travel times. However, GPR data provide further information that could be used in order to determine the inner conditions and characteristics about materials. In this paper, the possible analysis of the frequency spectrum of GPR signals is analysed and discussed. Several tests were carried out in a portion of a highway in two different stages of its service life. Results highlight the relationship between the shape of the spectrum and the frequency signature with the structure and conditions of the pavement.Efecto del procedimiento de compactación en laboratorio sobre la densidad y características mecánicas de las mezclas asfálticasMiró Recasens, José RodrigoPérez Jiménez, Félix EdmundoMartínez Reguero, Adriana HaydéeBotella Nieto, Ramónhttp://hdl.handle.net/2117/285222022-10-09T09:58:40Z2015-07-06T12:46:56ZEfecto del procedimiento de compactación en laboratorio sobre la densidad y características mecánicas de las mezclas asfálticas
Miró Recasens, José Rodrigo; Pérez Jiménez, Félix Edmundo; Martínez Reguero, Adriana Haydée; Botella Nieto, Ramón
El procedimiento de compactación en laboratorio más utilizado en España para la fabricación de probetas de mezcla bituminosa, sobre las que se realizarán los diferentes ensayos para su dosificación o caracterización mecánica, ha sido la compactación por impacto o procedimiento Marshall. Dependiendo del tipo de mezcla, se aplican 75 golpes por cara, en el caso de mezclas tipo hormigón bituminoso, o 50 goles por cara, en el caso de mezclas drenantes y discontinuas destinadas a capas de rodadura. Sin embargo, actualmente se plantea la posibilidad de utilizar otros métodos que reproduzcan mejor las condiciones de compactación en obra. En este sentido, la compactación con la máquina giratoria se perfila como el procedimiento alternativo a la compactación por impacto. El objetivo de este trabajo es analizar los dos procedimientos de compactación, impacto y giratoria, y conocer mejor sus similitudes y diferencias. Para ello se ha analizado el efecto de la compactación por impacto y de la giratoria sobre las propiedades volumétricas y mecánicas de una mezcla semidensa, tipo AC16 S. Los resultados ponen de manifiesto que la compactación Marshall lleva a obtener mezclas más densas, con menor contenido de huecos, y con mayores estabilidades y menores deformaciones y, consecuentemente, más rígidas, que las obtenidas con la compactación giratoria, y que el número de giros que produzca un efecto equivalente a un determinado número de golpes en el Marshall, variará en función, no solo del tipo de mezcla, sino también en función de cual sea su composición.
2015-07-06T12:46:56ZMiró Recasens, José RodrigoPérez Jiménez, Félix EdmundoMartínez Reguero, Adriana HaydéeBotella Nieto, RamónEl procedimiento de compactación en laboratorio más utilizado en España para la fabricación de probetas de mezcla bituminosa, sobre las que se realizarán los diferentes ensayos para su dosificación o caracterización mecánica, ha sido la compactación por impacto o procedimiento Marshall. Dependiendo del tipo de mezcla, se aplican 75 golpes por cara, en el caso de mezclas tipo hormigón bituminoso, o 50 goles por cara, en el caso de mezclas drenantes y discontinuas destinadas a capas de rodadura. Sin embargo, actualmente se plantea la posibilidad de utilizar otros métodos que reproduzcan mejor las condiciones de compactación en obra. En este sentido, la compactación con la máquina giratoria se perfila como el procedimiento alternativo a la compactación por impacto. El objetivo de este trabajo es analizar los dos procedimientos de compactación, impacto y giratoria, y conocer mejor sus similitudes y diferencias. Para ello se ha analizado el efecto de la compactación por impacto y de la giratoria sobre las propiedades volumétricas y mecánicas de una mezcla semidensa, tipo AC16 S. Los resultados ponen de manifiesto que la compactación Marshall lleva a obtener mezclas más densas, con menor contenido de huecos, y con mayores estabilidades y menores deformaciones y, consecuentemente, más rígidas, que las obtenidas con la compactación giratoria, y que el número de giros que produzca un efecto equivalente a un determinado número de golpes en el Marshall, variará en función, no solo del tipo de mezcla, sino también en función de cual sea su composición.Anticipar el futuro: una gran oportunidad para la ingenieríaMacias Arau, Perehttp://hdl.handle.net/2117/284992024-01-28T07:24:27Z2015-07-01T16:07:51ZAnticipar el futuro: una gran oportunidad para la ingeniería
Macias Arau, Pere
The author, a professor of urban planning legislation, retraces the pioneering and visionary role in contemporary planning of Udefons Cerda, the progressive urban planner responsible for designing Modern Barcelona. This prospectr/e capacity is brought up to our current, more complex times in which, in the words of the philosopher Daniel Inneranty, there is no longer an optimum solution for each problem and it ncr/v fails to the stakeholders appearing in the debate to conduct an arduous discussion process.
El autor, profesor de legislación urbanística, rememora el papel innovador y visionario que tuvo Ildefons Cerdà, el gran urbanista que planeó la Barcelona Moderna, en el diseño del futuro. Y traslada aquella capacidad prospectiva a los tiempos actuales, mucho más complejos, en los que, según detecta el filósofo Daniel Innerarity, ya no existe una solución óptima para cada problema por lo que sólo cabe que la pléyade de actores que aparecen en el debate lleven a cabo un arduo proceso de discusión.
2015-07-01T16:07:51ZMacias Arau, PereThe author, a professor of urban planning legislation, retraces the pioneering and visionary role in contemporary planning of Udefons Cerda, the progressive urban planner responsible for designing Modern Barcelona. This prospectr/e capacity is brought up to our current, more complex times in which, in the words of the philosopher Daniel Inneranty, there is no longer an optimum solution for each problem and it ncr/v fails to the stakeholders appearing in the debate to conduct an arduous discussion process.
El autor, profesor de legislación urbanística, rememora el papel innovador y visionario que tuvo Ildefons Cerdà, el gran urbanista que planeó la Barcelona Moderna, en el diseño del futuro. Y traslada aquella capacidad prospectiva a los tiempos actuales, mucho más complejos, en los que, según detecta el filósofo Daniel Innerarity, ya no existe una solución óptima para cada problema por lo que sólo cabe que la pléyade de actores que aparecen en el debate lleven a cabo un arduo proceso de discusión.Assessment of the adhesive capacity of asphalt binders in the aggregate-binder bonds by means of new methodologyValdés Vidal, Gonzalo A.Miró Recasens, José RodrigoMartínez Reguero, Adriana Haydéehttp://hdl.handle.net/2117/284982020-07-23T20:04:48Z2015-07-01T14:24:43ZAssessment of the adhesive capacity of asphalt binders in the aggregate-binder bonds by means of new methodology
Valdés Vidal, Gonzalo A.; Miró Recasens, José Rodrigo; Martínez Reguero, Adriana Haydée
The main goal of this study is to present a new methodology to characterize the adhesive capacity (cohesion and adhesion capacity) of asphalt binders by means of new mechanical parameters. This methodology is based on the Fenix test, a test recently developed in Spain. This method assesses the cracking resistance of the asphalt mixtures, and it has been adapted to characterize the bonding power of asphalt binders. The main parameters achieved with this procedure are related to the energy dissipated during the breaking between the asphalt binder and the aggregate, when these materials are subjected to tensile stress; essential parameters related to the adhesive capacity of asphalt binders. The results of an experimental stage are presented in this research, in which the proposed methodology has been applied to analyse the behaviour of the binder in the aggregate-binder matrix according to temperature variation and the effect of water and ageing; taking into account aggregates of the same origin and with a different shape pattern. The results show that the parameters achieved from this new methodology allows characterizing the adhesive capacity of asphalt binders in the different conditions assessed.
2015-07-01T14:24:43ZValdés Vidal, Gonzalo A.Miró Recasens, José RodrigoMartínez Reguero, Adriana HaydéeThe main goal of this study is to present a new methodology to characterize the adhesive capacity (cohesion and adhesion capacity) of asphalt binders by means of new mechanical parameters. This methodology is based on the Fenix test, a test recently developed in Spain. This method assesses the cracking resistance of the asphalt mixtures, and it has been adapted to characterize the bonding power of asphalt binders. The main parameters achieved with this procedure are related to the energy dissipated during the breaking between the asphalt binder and the aggregate, when these materials are subjected to tensile stress; essential parameters related to the adhesive capacity of asphalt binders. The results of an experimental stage are presented in this research, in which the proposed methodology has been applied to analyse the behaviour of the binder in the aggregate-binder matrix according to temperature variation and the effect of water and ageing; taking into account aggregates of the same origin and with a different shape pattern. The results show that the parameters achieved from this new methodology allows characterizing the adhesive capacity of asphalt binders in the different conditions assessed.Candilis-Josic-Woods y Le Corbusier: “Las ventanas no son un hueco en la pared”Fontana, Maria PiaMayorga Cárdenas, Miguel YuriAlzate, Edissonhttp://hdl.handle.net/2117/283632022-09-18T00:17:22Z2015-06-19T18:55:07ZCandilis-Josic-Woods y Le Corbusier: “Las ventanas no son un hueco en la pared”
Fontana, Maria Pia; Mayorga Cárdenas, Miguel Yuri; Alzate, Edisson
This article analyses the comparison between several of Candilis-Josic-Woods’ representative projects between 1947 and 1955 and Le Corbusier’s Villas and Unité works. Through this analysis it establishes the interaction between their approaches while simultaneously defining and exemplifying their general and specific contribution to the understanding of the façade as a space and not as a surrounding. Analysis of the thickness of the façade and of its relation with the interior and exterior space is an important design criterion when contemplating a more urban architecture, and an architecture that is more liveable and more integrated with the environment. This is a quality that is ever more relevant and pertinent as an answer to the densification and horizontalization of cities.
2015-06-19T18:55:07ZFontana, Maria PiaMayorga Cárdenas, Miguel YuriAlzate, EdissonThis article analyses the comparison between several of Candilis-Josic-Woods’ representative projects between 1947 and 1955 and Le Corbusier’s Villas and Unité works. Through this analysis it establishes the interaction between their approaches while simultaneously defining and exemplifying their general and specific contribution to the understanding of the façade as a space and not as a surrounding. Analysis of the thickness of the façade and of its relation with the interior and exterior space is an important design criterion when contemplating a more urban architecture, and an architecture that is more liveable and more integrated with the environment. This is a quality that is ever more relevant and pertinent as an answer to the densification and horizontalization of cities.Using spectral finite elements for parametric analysis of the vibration reduction index of heavy junctions oriented to flanking transmissions and EN-12354 prediction methodPoblet-Puig, JordiGuigou-Carter, Catherinehttp://hdl.handle.net/2117/281042020-07-23T20:56:31Z2015-05-29T13:52:00ZUsing spectral finite elements for parametric analysis of the vibration reduction index of heavy junctions oriented to flanking transmissions and EN-12354 prediction method
Poblet-Puig, Jordi; Guigou-Carter, Catherine
The vibration reduction index of heavy junctions is predicted by means of a model based on spectral finite elements. This is equivalent to a finite element method but faster and with smaller computational costs. This advantage is used in order to perform a parametric analysis of the vibration reduction index for several junction types: T-shaped, L-shaped and +-shaped. The influence of several parameters such as: damping, junction dimensions or the mass ratio on the vibration reduction index is observed. The study is focussed to provide data and guidelines oriented to the EN-12354 design method for flanking transmission in buildings.
2015-05-29T13:52:00ZPoblet-Puig, JordiGuigou-Carter, CatherineThe vibration reduction index of heavy junctions is predicted by means of a model based on spectral finite elements. This is equivalent to a finite element method but faster and with smaller computational costs. This advantage is used in order to perform a parametric analysis of the vibration reduction index for several junction types: T-shaped, L-shaped and +-shaped. The influence of several parameters such as: damping, junction dimensions or the mass ratio on the vibration reduction index is observed. The study is focussed to provide data and guidelines oriented to the EN-12354 design method for flanking transmission in buildings.Repercusión de la calidad de la construcción del firme en su deterioro y en los costes de conservaciónPérez Jiménez, Félix EdmundoMiró Recasens, José Rodrigohttp://hdl.handle.net/2117/279552022-09-11T12:08:57Z2015-05-18T15:24:35ZRepercusión de la calidad de la construcción del firme en su deterioro y en los costes de conservación
Pérez Jiménez, Félix Edmundo; Miró Recasens, José Rodrigo
La calidad estructural de un firme flexible está asociada básicamente a su nivel de deflexión. Para conseguir esta calidad durante su construcción debemos proceder periódicamente a la medida de su deflexión. La Instrucción de Carreteras (MF 2003) ya establece unos niveles de deflexión para comprobar la calidad y categoría de la explanada. Similares requisitos podrían establecerse para evaluar la calidad estructural de las capas del firme. El análisis estructural de los firmes de la Instrucción muestra que las secciones estructurales de firmes flexibles para una misma categoría de tráfico, presentan niveles
de deflexión similares. En relación a estos valores y a partir del control de la evolución de la deflexión de firmes en construcción se proponen unos niveles de deflexión para cada categoría de tráfico. Por otra parte, se ha valorado mediante la aplicación del sistema de gestión de firmes GSF, el efecto que tiene las variaciones de la calidad estructural conseguida en la construcción de un firme en las actuaciones y costes de su conservación. Este estudio muestra la enorme repercusión que tiene la menor calidad conseguida en la construcción del firme en sus costes de conservación.
2015-05-18T15:24:35ZPérez Jiménez, Félix EdmundoMiró Recasens, José RodrigoLa calidad estructural de un firme flexible está asociada básicamente a su nivel de deflexión. Para conseguir esta calidad durante su construcción debemos proceder periódicamente a la medida de su deflexión. La Instrucción de Carreteras (MF 2003) ya establece unos niveles de deflexión para comprobar la calidad y categoría de la explanada. Similares requisitos podrían establecerse para evaluar la calidad estructural de las capas del firme. El análisis estructural de los firmes de la Instrucción muestra que las secciones estructurales de firmes flexibles para una misma categoría de tráfico, presentan niveles
de deflexión similares. En relación a estos valores y a partir del control de la evolución de la deflexión de firmes en construcción se proponen unos niveles de deflexión para cada categoría de tráfico. Por otra parte, se ha valorado mediante la aplicación del sistema de gestión de firmes GSF, el efecto que tiene las variaciones de la calidad estructural conseguida en la construcción de un firme en las actuaciones y costes de su conservación. Este estudio muestra la enorme repercusión que tiene la menor calidad conseguida en la construcción del firme en sus costes de conservación.