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Weimar, Germany

The Bauhaus University is a university located in Weimar, Germany and specializes in the artistic and technical fields. Established in 1860 as the Great Ducal Saxon Art School, it gained collegiate status on 3 June 1910. In 1919 the school was renamed Bauhaus by its new director Walter Gropius and it received its present name in 1996. Approximately 4,000 students are enrolled at the university today.Along with the University of Erfurt, the University of Jena and the Ilmenau University of Technology, the Weimar Bauhaus University is one of the four universities in the Free State of Thuringia. In 2010 the Bauhaus University commemorated its 150th anniversary as an art school and college in Weimar. Wikipedia.

In this paper several methods for model assessment considering uncertainties are discussed. Sensitivity analysis is performed to quantify the influence of the individual model input parameters. In addition to the well-known analysis of a single model, a new procedure for quantifying the influence of the model choice on the uncertainty of the model prediction is proposed. Furthermore, a procedure is presented which can be used to estimate the model framework uncertainty and which enables the selection of the optimal model with the best compromise between model input and framework uncertainty. Finally Bayesian methods for model selection are extended for model assessment without measurements using model averaging as reference. © 2011 Elsevier Ltd. All rights reserved. Source

Unger J.F.,Northwestern University | Eckardt S.,Bauhaus University Weimar
Archives of Computational Methods in Engineering | Year: 2011

In this paper, a mesoscale model of concrete is presented, which considers particles, matrix material and the interfacial transition zone (ITZ) as separate constituents. Particles are represented as ellipsoides, generated according to a prescribed grading curve and placed randomly into the specimen. Algorithms are proposed to generate realistic particle configurations efficiently. The nonlinear behavior is simulated with a cohesive interface model for the ITZ. For the matrix material, different damage/plasticity models are investigated. The simulation of localization requires to regularize the solution, which is performed by using integral type nonlocal models with strain or displacement averaging. Due to the complexity of a mesoscale model for a realistic structure, a multiscale method to couple the homogeneous macroscale with the heterogeneous mesoscale model in a concurrent embedded approach is proposed. This allows an adaptive transition from a full macroscale model to a multiscale model, where only the relevant parts are resolved on a finer scale. Special emphasis is placed on the investigation of different coupling schemes between the different scales, such as the mortar method and the arlequin method, and a discussion of their advantages and disadvantages within the current context. The applicability of the proposed methodology is illustrated for a variety of examples in tension and compression. © 2011 CIMNE, Barcelona, Spain. Source

Lahmer T.,Bauhaus University Weimar
Inverse Problems | Year: 2011

The safe operation of gravity dams requires continuous monitoring in order to detect any changes concerning the stability of these constructions. Damage which may result from cyclic loading, variation in temperature, aging, chemical reactions, etc needs to be identified as fast and as reliable as possible. Generally, existing dams are well monitored by several types of measurement devices which log different physical quantities. The monitoring practice is according to official guidelines and the engineers experience. The aim of this paper is to perform a simulation-based optimal design for the monitoring of existing dams. Therefore, a design criterion which is based on average mean-squared reconstruction errors is derived. The reconstructions are obtained as regularized solutions of the nonlinear, inverse and ill-posed problem of damage identification. The basis for these investigations is a hydro-mechanically coupled model applied to gravity dams. Damaged zones in the dams are described by a smeared crack model, i.e. by spatially varying material properties. The inherent correlation of changes in the dominating parameters is explicitly considered during the inverse analysis. For the solution and regularization of the inverse problem, the iteratively regularized Gauss-Newton method is applied. Numerical results of the inverse analysis and the design process allow assessments of the applicability of the strategies proposed here. © 2011 IOP Publishing Ltd. Source

Adamatzky A.,University of the West of England | Schubert T.,Bauhaus University Weimar
Materials Today | Year: 2014

We demonstrate how logical operations can be implemented in ensembles of protoplasmic tubes of acellular slime mold Physarum polycephalum. The tactile response of the protoplasmic tubes is used to actuate analogs of two- and four-input logical gates and memory devices. The slime mold tube logical gates display results of logical operations by blocking flow in mechanically stimulated tube fragments and redirecting the flow to output tube fragments. We demonstrate how XOR and NOR gates are constructed. We also exemplify circuits of hybrid gates and a memory device. The slime mold based gates are non-electronic, simple and inexpensive, and several gates can be realized simultaneously at sites where protoplasmic tubes merge. © 2014 Elsevier Ltd. Source

The invention relates to a method for operating a multi-touch-capable display and to a device having computer functionality. In one step of the method, contents that can be manipulated are shown on the display. The contents comprise hierarchically structured interaction objects of two hierarchy levels. In further steps, a first touch and a second touch of the display are detected, which leads to information about said touches. The information about the first touch is used to manipulate interaction objects of the first hierarchy level. According to the invention, the information about the second touch is used to manipulate interaction objects of the second hierarchy level if the second touch is detected more than a certain length of time after the first touch and the first touch is still detected. In contrast, the information about the second touch is used to manipulate interaction objects of the first hierarchy level if the second touch is detected not more than the certain length of time after the first touch.

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