Investigación

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Documentos generados por los docentes e investigadores de la Universidad en su labor de investigación científica producida o editada por los departamentos y centros de la Universitat Politècnica de València.

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3D Point Cloud and GIS Approach to Assess Street Physical Attributes
(MDPI AG, 2024-06) Orozco Carpio, Patricio Rodrigo; Viñals Blasco, Mª José; López González, María Concepción; Dpto. de Expresión Gráfica Arquitectónica; Dpto. de Ingeniería Cartográfica Geodesia y Fotogrametría; Escuela Técnica Superior de Arquitectura; Centro de Investigación en Ingeniería Mecánica; Escuela Técnica Superior de Ingeniería de Edificación; Centro de Investigación en Métodos de Producción de Software - ProS; Centro de Investigación en Arquitectura, Patrimonio y Gestion para el desarrollo Sostenible; AGENCIA ESTATAL DE INVESTIGACION; Universitat Politècnica de València
[EN] The present research explores an innovative approach to objectively assessing urban streets attributes using 3D point clouds and Geographic Information Systems (GIS). Urban streets are vital components of cities, playing a significant role in the lives of their residents. Usually, the evaluation of some of their physical attributes has been subjective, but this study leverages 3D point clouds and digital terrain models (DTM) to provide a more objective perspective. This article undertakes a microurban analysis of basic physical characteristics (slope, width, and human scale) of a representative street in the historic centre of Valencia (Spain), utilizing 3D laser-scanned point clouds and GIS tools. Applying the proposed methodology, thematic maps were generated, facilitating the objective identification of areas with physical attributes more conducive to suitable pedestrian dynamics. This approach provides a comprehensive understanding of urban street attributes, emphasizing the importance of addressing their assessment through advanced digital technologies. Moreover, this versatile methodology has diverse applications, contributing to social sustainability by enhancing the quality of urban streets and open spaces.
A direct method for the extension of FastSim under non-Hertzian contact conditions
(Taylor & Francis, 2023-10-03) Gómez-Bosch, Jorge; Giner Navarro, Juan; Carballeira Morado, Javier; Baeza González, Luis Miguel; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Generalitat Valenciana; Agencia Estatal de Investigación; European Regional Development Fund; Ministerio de Ciencia e Innovación
[EN] In wheel-rail contact mechanics, there coexist different models characterised by their ability to reproduce the real phenomenon and the time associated with computing the solution. In simulation of the vehicle dynamics, the increase in the computational performance places researchers close to a horizon in which it is possible to implement the most realistic theories (Variational Theory or finite elements), although at present the use of these models is mainly limited to offline calculations, far from real-time simulation. In this context, this work presents a tangential contact theory that is an intermediate point between simplified models (unable to model non-Hertzian contact) and more realistic models (whose complexity triggers simulation times). The tangential contact model proposed is based on the FastSim algorithm, whose precision comes from the algorithm convergence to the results of an exact adhesion theory (i.e. when creepages tend to zero). The impossibility of considering Kalker's Linear Theory as an adjustment method when the hypotheses of the Hertzian model are not fulfilled leads to the adoption of the Kalker's steady-state CONTACT version in adhesion conditions. The calculations presented through the proposed algorithm provide errors for creep forces lower than 4% with computational times one order lower than the Variational Theory.
A finite element approach for the acoustic modelling of perforated dissipative mufflers with non-homogeneous properties
(Elsevier, 2013-04) Antebas, A.; Denia Guzmán, Francisco David; Pedrosa Sanchez, Ana Maria; Fuenmayor Fernández, Francisco Javier; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Ministerio de Educación y Ciencia
[EN] In this work, a finite element approach is presented for modeling sound propagation in perforated dissipative mufflers with non-homogeneous properties. The spatial variations of the acoustic properties can arise, for example, from uneven filling processes during manufacture and degradation associated with the flow of soot particles within the absorbent material. First, the finite element method is applied to the wave equation for a propagation medium with variable properties (outer chamber with absorbent material) and a homogeneous medium (central passage). For the case of a dissipative muffler, the characterization of the absorbent material is carried out by means of its equivalent complex density and speed of sound. To account for the spatial variations of these properties, a coordinate-dependent function is proposed for the filling density of the absorbent material. The coupling between the outer chamber and the central passage is achieved by using the acoustic impedance of the perforated central pipe, that relates the acoustic pressure jump and the normal velocity through the perforations. The acoustic impedance of the perforated central duct includes the influence of the absorbent material and therefore a spatial variation of the impedance is also taken into account. A detailed study is then presented to assess the influence of the heterogeneous properties and the perforated duct porosity on the acoustic attenuation performance of the muffler.
A framework to predict the airborne noise inside railway vehicles with application to rolling noise
(Elsevier, 2021-08) Li, Hui; Thompson, David; Squicciarini, Giacomo; Liu, Xiaowan; Rissmann, Martin; Bouvet, Pascal; Denia Guzmán, Francisco David; Baeza González, Luis Miguel; Martin Jarillo, Julian; Moreno Garcia-Loygorri, Juan; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; SHIFT2RAIL JOINT UNDERTAKING
[EN] A framework is described for predicting the airborne noise inside railway vehicles which is applied to rolling noise sources. Statistical energy analysis (SEA) is used to predict the interior noise by subdividing the train cabin into several subsystems. The dissipation loss factors are obtained from the measured reverberation time in the train cabin. The power input to the interior SEA model is obtained from the external noise sources by multiplying the incident sound power on the external surfaces with measured transmission coefficients of the train floor and sidewalls. The sound power incident on the train floor is calculated by using an equivalent source model for the wheels and track together with an SEA model of the region below the floor. The incident sound power on the sides is obtained by using a waveguide boundary element (2.5D BE) method. The procedure is applied to a Spanish metro train vehicle running in the open field for which rolling noise is the main external noise source. The procedure is verified by field measurements of sound pressure beneath the carriage, on the sidewalls and inside the vehicle. The sensitivity of the results to changes in interior absorption is also studied, including the effect of passengers.
A learning activity designed for a large group of students in a mechanical engineering subject using peer-assessment to encourage deeper learning
(IATED Academy, 2020-07-07) Suñer Martinez, Josep Lluis; Carballeira Morado, Javier; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Universitat Politècnica de València
[EN] This paper presents a learning activity for the subject "Machines and Mechanisms" in a bachelor¿s degree in Electrical Engineering that allows to work on several specific and generic competences for a large group of students. This activity consists of seeking a real mechanism and following some steps to analyze it, so that the students can improve their knowledge and understanding of the subject area. This activity is planned in a way that forces the students to put different skills into play, further than just dealing with the technical issues of it. Peer-assessment is carried out alongside the activity to encourage deeper learning. A full description of the activity is presented, together with the assessment tools and the results for this course.
A model of a rotating railway wheel for the prediction of sound radiation
(Elsevier, 2023-06-09) Andrés-Ruiz, Víctor Tomás; Martínez Casas, José; Denia Guzmán, Francisco David; Thompson, D.J.; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; GENERALITAT VALENCIANA; Ministerio de Universidades; AGENCIA ESTATAL DE INVESTIGACION; MINISTERIO DE CIENCIA E INNOVACION; Universitat Politècnica de València
[EN] The axial symmetry of a railway wheel is taken into account to expand its vibrational response around the circumferential direction using Fourier series. This allows the vibroacoustic problem of the wheel to be formulated in a two-dimensional frame, solving for the dynamic and acoustic variables analytically in the circumferential direction. By adopting an Eulerian approach, the inertial effects associated with the rotation of the wheelset are included in the model, assuming a constant angular speed of rotation. To represent a railway wheelset, the wheel is constrained at the inner edge of the hub and the contribution of the rigid body motion of the wheelset is superimposed on its response. The latter is evaluated analytically under the assumption of small rigid body displacements. The computational efficiency of the proposed methodology is found to be three orders of magnitude greater than a full three-dimensional methodology, without compromising the accuracy. The results are compared in terms of acoustic radiation with the commercial package Ansys, showing similar sound power levels in almost all the frequency range apart from some differences at low frequencies due to the use of an acoustic model based on radiation ratios.
A new approach to the kinematic modeling of a three-dimensional car-like robot with differential drive using computational mechanics
(SAGE Publications, 2019-03-13) Rubio Montoya, Francisco José; Llopis Albert, Carlos; Valero Chuliá, Francisco José; Besa Gonzálvez, Antonio José; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica
[EN] This article presents a kinematic analysis of a four-wheeled mobile robot in three-dimensions, introducing computational mechanics. The novelty lies in (1) the type of robot that is analyzed, which has been scarcely dealt with in the literature, and (2) the methodology used which enables the systematic implementation of kinematic algorithms using the computer. The mobile robot has four wheels, four rockers (like an All-Terrain Mobile Robot), and a main body. It also has two actuators and uses a drive mechanism known as differential drive (like those of a slip/skid mobile robot). We characterize the mobile robot as a set of kinematic closed chains with rotational pairs between links and a higher contact pair between the wheels and the terrain. Then, a set of generalized coordinates are chosen and the constraint equations are established. A new concept named ¿driving modes¿ has been introduced because some of the constraint equations are derived from these. The kinematics is the first step in solving the dynamics of this robot in order to set a control algorithm for an autonomous car-like robot. This methodology has been successfully applied to a real mobile robot, ¿Robotnik,¿ and the results are analyzed.
Acoustic characteristics of circular dissipative reversing chamber mufflers
(Institute of Noise Control Engineering, 2011) Denia Guzmán, Francisco David; Antebas, Antoine; Selamet, A.; Pedrosa Sanchez, Ana Maria; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Ministerio de Economía, Industria y Competitividad
[EN] In this work, a three-dimensional analytical model is presented for the propagation of sound in circular dissipative reversing chamber mufflers with perforated frontal plates and bulk-reacting fibrous material. The procedure is based on the mode matching method that couples the acoustic pressure and particle velocity at each geometrical discontinuity, and includes the presence of axisymmetric as well as asymmetric modes in the air regions and also within the absorbent material. The complex characteristic impedance and wavenumber are taken into account to model the sound propagation in the bulk-reacting fibrous material. To validate the procedure, the analytical muffler transmission loss predictions are compared with finite element results, showing a good agreement. A detailed study is then performed to assess the acoustical effect of the resistivity of the absorbent material, the porosity of the perforated plates and the main geometrical parameters, such as the location of inlet/outlet ducts, the thickness of the dissipative region and its axial location. © 2011 Institute of Noise Control Engineering.
Acoustic modeling of perforated concrete using the dual porosity theory
(Elsevier, 2017-01-01) Carbajo San Martín, Jesús; Esquerdo Lloret, Tomás Vicente; Ramis Soriano, Jaime; Nadal Gisbert, Antonio Vicente; Denia Guzmán, Francisco David; Dpto. de Ingeniería Mecánica y de Materiales; Instituto de Diseño para la Fabricación y Producción Automatizada; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Escuela Politécnica Superior de Alcoy
[EN] Perforated concrete shows nowadays a high potential for many construction and building engineering applications. This work is devoted to the analysis of the acoustic properties of perforated concrete made from arlite lightweight aggregates. Concrete produced from these materials is an environmentally friendly alternative to traditional materials and offers a higher durability, excellent strength-to-weight ratio and low cost. In particular, it is shown that the acoustic behavior of perforated concrete can be modeled using a dual porosity approach based on the knowledge of the non-acoustic properties of the matrix granular material and geometrical data. To this end, various non-perforated and perforated samples were prepared and characterized in an experimental test facility, their acoustic properties being determined through the transfer function impedance tube method. Experimental and estimated results related to the acoustic properties of a number of prepared specimens are presented, showing a good agreement. Results suggest that this approach is suitable for practical design of such materials as part of noise control systems. (C) 2016 Elsevier Ltd. All rights reserved.
Acoustic modelling of large aftertreatment devices with multimodal incident sound fields
(Universitat Politècnica de València, 2021-11-30) Denia Guzmán, Francisco David; Sánchez Orgaz, Eva María; Martínez Casas, José; Carballeira Morado, Javier; Baeza González, Luis Miguel; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial
[EN] The influence of multimodal incident sound fields on the acoustic behaviour of large aftertreatment devices (ATD) is analysed in detail. The mode matching method is applied to the compatibility conditions of the three-dimensional (3D) acoustic fields at the device geometric discontinuities, leading to the computation of the complex wave amplitudes in all the subdomains involved and the corresponding transmission loss (TL). To have a realistic model, 3D propagation must be considered in the inlet/outlet ducts and chambers, while 1D wave propagation has to be assumed along the small capillaries of the catalytic converter/particulate filter monoliths of the ATD; therefore, these monoliths can be replaced by plane wave four pole transfer matrices from an acoustical point of view [1]. On the other hand, for large ATD inlet ducts such as those found in heavy-duty and off-road engines, the usual models with plane incident wave excitation are not accurate since the onset of higher order incident modes in the inlet duct is expected for the frequency range of interest. Therefore, a TL variation is likely to occur depending on these modes, similar to the results found in large dissipative silencers [2]. Results are presented for three different multimodal incident sound field hypotheses [3]: equal modal amplitude (EMA), equal modal power (EMP) and equal modal energy density (EMED). A relevant influence on the sound attenuation is found for the test problems considered in the current investigation. References [1] Denia, F. D., Martínez-Casas, J., Carballeira, J., Nadal, E., Fuenmayor, F. J., Computational performance of analytical methods for the acoustic modelling of automotive exhaust devices incorporating monoliths. Journal of Computational and Applied Mathematics, 330: 995--1006, 2018. [2] Kirby, R., Lawrie, J. B., A point collocation approach to modelling large dissipative silencers. Journal of Sound and Vibration, 286: 313--339, 2005. [3] Mechel, F. P., Formulas of Acoustics. Berlin, Springer, 2008.
Acoustic properties of porous concrete made from arlite and vermiculite lightweight aggregates
(CSIC, 2015) Carbajo San Martín, Jesús; Esquerdo Lloret, Tomás Vicente; Ramis Soriano, Jaime; Nadal Gisbert, Antonio Vicente; Denia Guzmán, Francisco David; Dpto. de Ingeniería Mecánica y de Materiales; Instituto de Diseño para la Fabricación y Producción Automatizada; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Escuela Politécnica Superior de Alcoy
[EN] The use of sustainable materials is becoming a common practice for noise abatement in building and civil engineering industries. In this context, many applications have been found for porous concrete made from lightweight aggregates. This work investigates the acoustic properties of porous concrete made from arlite and vermiculite lightweight aggregates. These natural resources can still be regarded as sustainable since they can be recycled and do not generate environmentally hazardous waste. The experimental basis used consists of different type specimens whose acoustic performance is assessed in an impedance tube. Additionally, a simple theoretical model for granular porous media, based on parameters measurable with basic experimental procedures, is adopted to predict the acoustic properties of the prepared mixes. The theoretical predictions compare well with the absorption measurements. Preliminary results show the good absorption capability of these materials, making them a promising alternative to traditional porous concrete solutions.
Advanced numerical techniques for the acoustic modelling of materials and noise control devices in the exhaust system of internal combustion engines
(Universitat Politècnica de València, 2016-05-16) Sánchez Orgaz, Eva María; Denia Guzmán, Francisco David; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial
[EN] This Thesis is focused on the development and implementation of efficient numerical methods for the acoustic modelling and design of noise control devices in the exhaust system of combustion engines. Special attention is paid to automotive perforated dissipative silencers, in which significant differences are likely to appear in their acoustic behaviour, depending on the temperature variations within the absorbent material. Also, material heterogeneities can alter the silencer attenuation performance. Therefore, numerical techniques considering all these features are required to guarantee the accuracy of the results. A literature review is carried out, mainly related to one-dimensional models, as well as to acoustic models for absorbent materials and perforated surfaces. However, plane wave model limitations make indispensable using alternative multidimensional methods. In addition, the possibility of using new acoustic elements is explored. These elements have as an objective being a potential alternative to the fibrous absorbent materials, which can have a negative impact on health. The Thesis considers the use of microperforated and sintered surfaces. The latter have, in some cases, a nearly constant acoustic impedance, whose value depends, among others, on the thickness and porosity of the plates. To avoid the limitations of plane wave models, a finite element (FE) approach is proposed for the acoustic analysis of dissipative silencers including a perforated duct with uniform axial mean flow and an outer chamber with a heterogeneous distribution of the absorbent material. On the other hand, property variations can be also produced by temperature gradients. In this case, a hybrid FE model has been derived for perforated dissipative silencers including: (1) Thermal gradients in the central duct and the chamber; (2) A perforated passage carrying non-uniform axial mean flow. A FE approach has been implemented to solve the pressure-based wave equation for a non-moving heterogeneous medium, associated with the chamber. Also, the governing equation in the central duct has been written and solved in terms of an acoustic velocity potential to allow the presence of an axially inhomogeneous flow. The coupling between both regions has been carried out by means of a perforated duct and its acoustic impedance, adapted here to include absorbent material heterogeneities and mean flow effects. It has been found that the presence of non-homogeneities can have a significant influence on the acoustic attenuation of a silencer and should be included in the theoretical models. Optimization techniques for industrial noise control devices are relevant, since they lead to the production of elements with better characteristics. Evolutionary algorithms are emergent techniques able to obtain a solution, even in those problems in which the traditional optimization have difficulties. Optimization techniques are combined with the FE method to achieve the maximum attenuation in the frequency range of interest. A multichamber silencer optimization problem is defined and several analyses are carried out to obtain the most suitable configuration for each application. Under certain assumptions of axial uniformity, several techniques have been considered to reduce the computational effort of a full 3D FE analysis for dissipative silencers with temperature gradients and mean flow. These are based on a decomposition of the acoustic field into transversal and axial modes within each silencer subdomain, and a matching procedure of the modal expansions at the silencer area changes through the continuity conditions of the acoustic fields. The relative computational efficiency and accuracy of predictions for the matching techniques are studied, including point collocation at nodes and Gauss points and also mode-matching with weighted integration. All of them provide accurate predictions of the attenuation and improve the computational cost of a FE calculation
Análisis gráfico del proyecto, el sistema constructivo y la estructura de la Fundación Calouste Gulbenkian de Lisboa
(Universidad Autónoma de Encarnación, 2022-04-02) Eixerés Ros, Josep; Giménez Ribera, Manuel; Cabrera Fausto, Ivan; Dpto. de Expresión Gráfica Arquitectónica; Escuela Técnica Superior de Arquitectura; Dpto. de Mecánica de los Medios Continuos y Teoría de Estructuras; Centro de Investigación en Ingeniería Mecánica; Centro de Investigación en Métodos de Producción de Software - ProS; Centro de Investigación en Arquitectura, Patrimonio y Gestion para el desarrollo Sostenible
[EN] On his death in 1955, Calouste Gulbenkian left his legacy to the Government of Portugal, favoring the creation of one of the most sensitive architectures in the country, the Calouste Gulbenkian Foundation. Through the language of architecture, drawing, the project is studied by means of the analysis of the original drafts and blueprints. Issues such as use, presentation modes and graphic techniques define the components of any drawing, whose ultimate goal is to contribute to the evolution and development of architecture. Drawings made from an existing reality are intended, not much for the interest that reflects its documentary quality, but for an analysis material for the complete understanding of the work, from the history of the place to the structural solutions developed for each of the projected buildings.
Análisis morfológico de mezclas de materiales compuestos de matriz cementicia con aligerantes para la construcción
(Compobell, S.L., 2013-11-12) Esquerdo Lloret, Tomás Vicente; Nadal Gisbert, Antonio Vicente; Denia Guzmán, Francisco David; Crespo Amorós, José Enrique; Pérez Pérez, Luis Miguel; Dpto. de Ingeniería Mecánica y de Materiales; Instituto de Diseño para la Fabricación y Producción Automatizada; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Instituto de Tecnología de Materiales; Escuela Politécnica Superior de Alcoy
[ES] En este trabajo se estudia la granulometría en distintas composiciones de mezcla de cemento, agua y materiales aligerantes. Empleamos la Vermiculita de dos granulometrías (V2 y V3) y se determina la composición más adecuada de cemento y agua para disponer de muestras que tengan cohesión suficiente para su fácil manejo.Se emplea como adhesivo Cemento Portland. El empleo de técnicas de análisis de imagen mediante programas informáticos específicos de estudio de partículas resulta ventajoso frente a software de diseño gráfico (AUTOCAD). El uso de este tipo de programas supone un esfuerzo adicional debido a que cada partícula o grano debe tratarse individualmente, resultando un trabajo tedioso y de baja fiabilidad, debiendo analizarse al menos entre 50 y 100 partículas o granos.
Analysis of the backward bending modes in damped rotating beams
(SAGE Publications, 2019-04-11) Martínez Casas, José; Denia Guzmán, Francisco David; Fayos Sancho, Juan; Nadal Soriano, Enrique; Giner Navarro, Juan; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Generalitat Valenciana; Agencia Estatal de Investigación; Union des Industries Ferroviaires Européennes; Shift2Rail Joint Undertaking
[EN] This article presents a study of the backward bending mode of a simply supported rotating Rayleigh beam with internal damping. The study analyses the natural frequency behaviour of the backward mode according to the internal viscous damping ratio, the slenderness of the beam and its spin speed. To date, the behaviour of the natural frequency of the backward mode is known to be a monotonically decreasing function with spin speed due to gyroscopic effects. In this article, however, it is shown that this behaviour of the natural frequency may not hold for certain damping and slenderness conditions, and reaches a minimum value (concave function) from which it begins to increase. Accordingly, the analytical expression of the spin speed for which the natural frequency of the backward mode attains the minimum value has been obtained. In addition, the internal damping ratio and slenderness intervals associated with such behaviour have been also provided.
Analysis of the Current Status of Sensors and HBIM Integration: A Review Based on Bibliometric Analysis
(MDPI AG, 2024-04) Vieira de Souza Rolim, Renan Cornélio; López González, María Concepción; Viñals Blasco, Mª José; Dpto. de Expresión Gráfica Arquitectónica; Dpto. de Ingeniería Cartográfica Geodesia y Fotogrametría; Escuela Técnica Superior de Arquitectura; Centro de Investigación en Ingeniería Mecánica; Escuela Técnica Superior de Ingeniería de Edificación; Centro de Investigación en Métodos de Producción de Software - ProS; Centro de Investigación en Arquitectura, Patrimonio y Gestion para el desarrollo Sostenible; Ministerio de Universidades; AGENCIA ESTATAL DE INVESTIGACION; Universitat Politècnica de València
[EN] This article presents a bibliometric analysis conducted on the implementation of sensor extracted data in the context of Historical Building Information Modeling (HBIM) with a focus on the conservation of heritage buildings. The study utilized recognized databases, namely, Web of Science (WoS) and Scopus. A bibliometric analysis methodology was applied, employing the VOSviewer 1.6.19 software. The results obtained provide a robust overview of the current state and trends in HBIM and sensor research and enabled the identification of emerging trends in the field of preventive conservation. Three promising trends were identified, establishing connections between this field and 4D spatial data management, energy performance, and artificial intelligence. Additionally, relations with climate change were also detected. These trends underscore a significant convergence of technologies and methodologies in the realm of heritage building conservation. The conclusions serve as a valuable contribution to guiding future research in the field of built heritage conservation.
Analysis of tourist flows and the comfort of guided tours in the Seu-Cathedral district of Valencia using participant observation and digital itinerary monitoring tools
(Editorial Universitat Politècnica de València, 2024-07-10) Teruel, Maria-Dolores; Viñals Blasco, Mª José; Orozco Carpio, Patricio Rodrigo; Dpto. de Expresión Gráfica Arquitectónica; Dpto. de Ingeniería Cartográfica Geodesia y Fotogrametría; Escuela Técnica Superior de Arquitectura; Centro de Investigación en Ingeniería Mecánica; Escuela Técnica Superior de Ingeniería de Edificación; Centro de Investigación en Métodos de Producción de Software - ProS; Centro de Investigación en Arquitectura, Patrimonio y Gestion para el desarrollo Sostenible
[ES] One of the challenges facing tourist destinations is to increase knowledge about aspects such as security concerning its implementation, measurement and evaluation to ensure the comfort of the visit. Tourist groups, both spontaneous and organised, that pass through the historic centre of a city are a permanent and fundamental element in the development of the tourist experience. However, it is necessary to know the routes taken by the guided groups to avoid concentrations of visitors that could impede mobility and hinder the daily lives of other residents. To obtain more information about this tourist activity, this study focuses on the study of the group's situations of insecurity and discomfort during the tour. The methodology consisted of participant observation on the routes usually followed by these guided groups applied to the Seu-Cathedral neighbourhood in Valencia. The Wikilocs tool was also used to monitor the route and detect the number of encounters and places of congestion. The results point to the need to plan the safety aspects of the visits, especially traffic and transit obstacles, the identification of congestion situations and the holding of periodic events, as well as the study of shaded areas and the incorporation of outdoor furniture to increase the number of visitors.
Analytical study of the effects of soft tissue artefacts on functional techniques to define axes of rotation
(Elsevier, 2017) De Rosario Martínez, Helios; Page Del Pozo, Alvaro Felipe; Besa Gonzálvez, Antonio José; Dpto. de Física Aplicada; Escuela Técnica Superior de Ingeniería de Telecomunicación; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Ministerio de Economía, Industria y Competitividad
[EN] The accurate location of the main axes of rotation (AoR) is a crucial step in many applications of human movement analysis. There are different formal methods to determine the direction and position of the AoR, whose performance varies across studies, depending on the pose and the source of errors. Most methods are based on minimizing squared differences between observed and modelled marker positions or rigid motion parameters, implicitly assuming independent and uncorrelated errors, but the largest error usually results from soft tissue artefacts (STA), which do not have such statistical properties and are not effectively cancelled out by such methods. However, with adequate methods it is possible to assume that STA only account for a small fraction of the observed motion and to obtain explicit formulas through differential analysis that relate STA components to the resulting errors in AoR parameters. In this paper such formulas are derived for three different functional calibration techniques (Geometric Fitting, mean Finite Helical Axis, and SARA), to explain why each technique behaves differently from the others, and to propose strategies to compensate for those errors. These techniques were tested with published data from a sit-to-stand activity, where the true axis was defined using bi-planar fluoroscopy. All the methods were able to estimate the direction of the AoR with an error of less than 5 degrees whereas there were errors in the location of the axis of 30-40 mm. Such location errors could be reduced to less than 17 mm by the methods based on equations that use rigid motion parameters (mean Finite Helical Axis, SARA) when the translation component was calculated using the three markers nearest to the axis. (C) 2017 Elsevier Ltd. All rights reserved.
Assessment of critical thinking within a subject related to mechanical engineering
(IATED, 2019-03-13) Giner Navarro, Juan; Sonseca Olalla, Agueda; Martínez Casas, José; Carballeira Morado, Javier; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Instituto de Tecnología de Materiales; Universitat Politècnica de València
[EN] The international accreditation of the programmes for the masters' and bachelors' degrees offered at our university, together with the demands of the employers, have made it clear that the students' curricula should specify not only what they have studied, but also what they are actually able to do. Although, in the recent years the competence based curricula approach has been used in the development of the new masters' and bachelors¿ degree programmes within the European Higher Education Area, the assessment of the generic competences is still a pending matter. This work presents an outcomes approach for the assessment of the capacity for critical thinking within subjects related to mechanical engineering. In particular, this paper proposes a methodology in order to quantify the level of achievement and shows one tool developed for that purpose. The tool is based on the evaluation of some learning outcomes that can be observed by asking the students about different issues related to the contents of the course. Conclusions about preliminary results and the difficulties found to create this tool are also described here.
Assessment of instrumental skills and capacity to use the techniques and tools in practice within a subject related to mechanical engineering
(IATED, 2019-03-13) Giner Navarro, Juan; Sonseca Olalla, Agueda; Carballeira Morado, Javier; Martínez Casas, José; Escuela Técnica Superior de Ingeniería del Diseño; Dpto. de Ingeniería Mecánica y de Materiales; Centro de Investigación en Ingeniería Mecánica; Instituto Universitario de Investigación Concertado de Ingeniería Mecánica y Biomecánica; Escuela Técnica Superior de Ingeniería Industrial; Instituto de Tecnología de Materiales; Universitat Politècnica de València
[EN] Over the last few years there is a high interest in developing new curricular programmes of the European Higher Education Area that adapt their masters' and bachelors' degrees to the demands of the employers. The international accreditation of these programmes is not limited to the evaluation of the subjects within the degrees, it also scores the generic and specific competences that will be achieved by the students. These competences are thought to evaluate what the students are actually able to do and therefore, they are useful not only to adapt the degrees to the existing European working model, but also to facilitate the students¿ incorporation into it. Nevertheless, the methodologies for the assessment of these competences are still a pending task that requires more learning experience. In order to contribute to the progress of this topic, this work presents an outcomes approach for the assessment of the students¿ ability to use the techniques, skills and tools for engineering related practical issues within mechanical engineering subjects. In particular, this paper designs individual questionnaires for IT and laboratory practices in order to quantify the domain level of the students in the usage of a commercial software and in the comprehension of technical and instrumental concepts. These tools are based on the evaluation of some learning outcomes that can be observed by using different strategies along the academic year. Some results regarding a first attempt to use this tool are also analysed in this paper. Finally, some conclusions are derived from these experiences in order to improve our proposal in the future.

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