Bauhaus University, Weimar

About: Bauhaus University, Weimar is a education organization based out in Weimar, Thüringen, Germany. It is known for research contribution in the topics: Finite element method & Isogeometric analysis. The organization has 1421 authors who have published 2998 publications receiving 104454 citations. The organization is also known as: Bauhaus-Universität Weimar & Hochschule für Architektur und Bauwesen.

Numerical study of transition zone between ballasted and ballastless railway track

Abstract: Track stiffness plays an important role in design and construction stages of the railway track. Smoother travel and longer life time of a track depend on the immutable track stiffness. Nevertheless, changing the track stiffness is inevitable, especially in the transition zone, where the slab track connects to a conventional ballasted track. In this zone track stiffness changes abruptly and it causes differential settlement, which is the main cause for degradation of tracks and foundations at transition zones. A number of remedies have been proposed or used to provide gradual stiffness transition, such as the use of gradual pad stiffness, long sleepers and auxiliary rail in the transition zone. The emphasis of this study is held on the assessment of the behavior of different types of the transition zone under the train moving loads. For that reason, well-known commercial finite-element method package has been used to investigate the dynamic behavior of the transition zone under the passage of high-speed trains. The results of the dynamic analysis are presented and compared in two circumstances; one considering the common improvement in the superstructure by installing auxiliary rails or gradually increasing the length of the sleepers in transition area, and the other by enhancing the substructure through constructing two-part transition section.

"I am just terrified of my future" Epistemic Violence in Disability Related Technology Research

Abstract: Technology for disabled people is often developed by non-disabled populations, producing an environment where the perspectives of disabled researchers - particularly when they clash with normative ways of approaching accessible technology - are denigrated, dismissed or treated as invalid. This epistemic violence has manifest material consequences for our lives as disabled researchers engaging with work on our own states of being. Through a series of vignettes, we illustrate our experiences and the associated pain that comes with such engagement as well as the consequences of pervasive dehumanization of ourselves through existing works. Our aim is to identify the epistemic injustice disabled people experience within HCI, to question the epistemological base of knowledge production leading to said injustice and to take ownership of a narrative that all too often is created without our participation.

Finite element model calibration of a railway vehicle based on experimental modal parameters

Abstract: This article describes the experimental calibration of a three-dimensional numerical model of an Alfa Pendular train vehicle based on modal parameters. The dynamic tests of the carbody and bogie of the vehicle allowed the determination of the frequencies and modal configurations of 13 vibration modes, by applying the data-driven stochastic subspace identification method. In addition, a dynamic characterisation test of the passenger-seat system was also conducted. The calibration of the model was performed using a submodelling/multistep approach involving two phases, the first one focused on the calibration of the model of the bogie under test conditions and the second one focused on the calibration of the complete model of the vehicle. The calibration was performed through an iterative method based on a genetic algorithm and allowed to obtain optimal values of 17 parameters of the numerical model. For the pairing of the vibration modes, real and complex, a recent technique was used based on the calculation of the modal strain energy. The stability of a significant number of parameters considering different initial populations demonstrated the robustness of the algorithm. The comparison of experimental and numerical responses before and after calibration revealed significant improvements in the numerical model and a very good correlation between the responses obtained with the calibrated model and the experimental responses.