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Beasain, Spain

Fridhi H.,University of Lille Nord de France | Deniau V.,University of Lille Nord de France | Ghys J.P.,University of Lille Nord de France | Heddebaut M.,University of Lille Nord de France | And 2 more authors.
Proceedings of the 2013 International Conference on Electromagnetics in Advanced Applications, ICEAA 2013 | Year: 2013

An in-depth analysis of the electromagnetic interferences generated by trains requires a better understanding of specific railway interference sources. Interferences due to the losses of contact between catenary and pantograph are among them This paper presents a modeling methodology proposed to analyze the effect of pantograph arcing on GSM-R antennas located on the train roof. The model was developed using the CST™ microwave studio tool. Comparisons were performed with experimental results to assess the quality of the simulation results. Finally, an analysis was carried out in order to discriminate the couplings between the GSM-R antenna and the different components of the model. © 2013 IEEE.

Garcia J.,Technical University of Madrid | Crespo A.,Technical University of Madrid | Berasarte A.,CAF ID | Goikoetxea J.,CAF
Journal of Wind Engineering and Industrial Aerodynamics | Year: 2011

The purpose of this work is to study the flow between the underbody of a high speed train and the ground, which consists of both ballast and sleepers. The flow is approximated by a turbulent Couette flow. An analytical solution of the turbulent Couette flow is proposed. Comparisons of the analytical results against wind tunnel and on track tests experiments and results of other classical models for turbulent Couette flows are made in order to validate the obtained solution. The analytical velocity profile is also compared with the corresponding one calculated with the commercial code Fluent for an idealized two-dimensional configuration. Another objective of this work is to obtain an equivalent roughness of the track made of sleepers and ballast. The results obtained enable stationary RANS simulations to be undertaken by substituting the track made of sleepers and ballast with an equivalent rough plate. This steady state analysis is not possible if the sleepers are retained. Taking into account the energy conservation, and comparing with the analytical solution, the equivalent roughness of the ballast track is obtained. The influence of the following parameters on the obtained values of the equivalent surface roughness is analyzed: height of the gap, Reynolds number and roughness of the upper wall. © 2011 Elsevier Ltd.

Polach O.,Bombardier | Bottcher A.,Alstom | Vannucci D.,Ansaldobreda S. P. A. | Sima J.,Siemens AG | And 8 more authors.
Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit | Year: 2015

The evaluation of a reliable validation method, criteria and limit values suitable for model validation in the context of vehicle acceptance was one of the objectives of the DynoTRAIN project. The presented investigations represent a unique amount of testing, simulations, comparisons with measurements, and validation evaluations. The on-track measurements performed in four European countries included several different vehicles on a test train equipped to simultaneously record track irregularities and rail profiles. The simulations were performed using vehicle models built with the use of different simulation tools by different partners. The comparisons between simulation and measurement results were conducted for over 1000 simulations using a set of the same test sections for all vehicle models. The results were assessed by three different validation approaches: comparing values according to EN 14363; by subjective engineering judgement by project partners; and using so-called validation metrics, i.e. computable measures developed with the aim of increasing objectivity while still maintaining the level of agreement with engineering judgement. The proposed validation method uses the values computed by analogy with EN 14363 and provides validation limits that can be applied to a set of deviations between simulation and measurement values. © MechE 2014.

Lotze E.,Stellenbosch University | Bergh O.,CAF
Acta Horticulturae | Year: 2015

The local fruit industry depends heavily on exportation of products. Profit margins are small, even in good seasons. This is largely due to the costs of contract factory labor and supplies, like tins and sugar, which need to be in stock at the beginning of the season. If the crops are down from the estimated, and orders placed based on these data, supplies would need to be carried until the next season, and labor would still need to be paid, regardless of the crop volume, which impacts on the profit margin. Thus, the contribution of an accurate crop estimate, early in the season, for planning in the factory is evident. At present, technical advisors provide the crops estimates. As the accuracy depends heavily on the experience of these advisors, a need arose to supplement their expertise with a prediction model, to ensure that this prediction will still be available and accurate in future, should the expertise become unavailable. A model was developed using historical crop volumes and various climatic parameters, in a multi linear regression. Then, it was validated against the following season's crop, as well as the crop estimates of the technical advisors. The accuracy of the prediction model was comparative to the technical estimate, and more accurate under specific climatic conditions that occurred irregularly. The model was applied commercially, during 2010/11.

Adin I.,University of Navarra | Mendizabal J.,University of Navarra | Arrizabalaga S.,University of Navarra | Alvarado U.,University of Navarra | And 2 more authors.
Measurement: Journal of the International Measurement Confederation | Year: 2016

The interoperability between on track balises and the on board Balise Transmission Module systems depends on both sides' susceptibility and allowed emissions. For that assessment, the document that governs the testing methodology, tools and procedures (Subset 116) needs to be completed prior to its publication. The present paper proposes an advance beyond the state of the art for the rolling stock emission assessment in terms of the test setup and of the post-processing procedure. The documentation commonly used in ERTMS-related issues has been analyzed and the common tools and procedures have been taken into consideration for the proposal presented by the authors. © 2015 Elsevier Ltd. All rights reserved.

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