@inproceedings{OPUS4-2451,
  title     = {International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 20 - 22 2015, Bauhaus-University Weimar},
  series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 20 - 22 2015, Bauhaus-University Weimar},
  booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 20 - 22 2015, Bauhaus-University Weimar},
  editor    = {G{\"u}rlebeck, Klaus and Lahmer, Tom},
  organization    = {Bauhaus-Universit{\"a}t Weimar},
  issn      = {1611-4086},
  doi       = {10.25643/bauhaus-universitaet.2451},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150828-24515},
  pages     = {230},
  abstract  = {The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference!},
  subject      = {Angewandte Informatik},
  language  = {en}
}
@phdthesis{Abbas,
  author    = {Abbas, Tajammal},
  title     = {Assessment of Numerical Prediction Models for Aeroelastic Instabilities of Bridges},
  publisher = {Jonas Verlag},
  address   = {Weimar},
  doi       = {10.25643/bauhaus-universitaet.2716},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20180515-27161},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {275},
  abstract  = {The phenomenon of aerodynamic instability caused by the wind is usually a major design criterion for long-span cable-supported bridges. If the wind speed exceeds the critical flutter speed of the bridge, this constitutes an Ultimate Limit State. The prediction of the flutter boundary, therefore, requires accurate and robust models. The complexity and uncertainty of models for such engineering problems demand strategies for model assessment. This study is an attempt to use the concepts of sensitivity and uncertainty analyses to assess the aeroelastic instability prediction models for long-span bridges. The state-of-the-art theory concerning the determination of the flutter stability limit is presented. Since flutter is a coupling of aerodynamic forcing with a structural dynamics problem, different types and classes of structural and aerodynamic models can be combined to study the interaction. Here, both numerical approaches and analytical models are utilised and coupled in different ways to assess the prediction quality of the coupled model.},
  subject      = {Br{\"u}cke},
  language  = {en}
}
@unpublished{AbbasKavrakovMorgenthaletal.,
  author    = {Abbas, Tajammal and Kavrakov, Igor and Morgenthal, Guido and Lahmer, Tom},
  title     = {Prediction of aeroelastic response of bridge decks using artificial neural networks},
  doi       = {10.25643/bauhaus-universitaet.4097},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200225-40974},
  abstract  = {The assessment of wind-induced vibrations is considered vital for the design of long-span bridges. The aim of this research is to develop a methodological framework for robust and efficient prediction strategies for complex aerodynamic phenomena using hybrid models that employ numerical analyses as well as meta-models. Here, an approach to predict motion-induced aerodynamic forces is developed using artificial neural network (ANN). The ANN is implemented in the classical formulation and trained with a comprehensive dataset which is obtained from computational fluid dynamics forced vibration simulations. The input to the ANN is the response time histories of a bridge section, whereas the output is the motion-induced forces. The developed ANN has been tested for training and test data of different cross section geometries which provide promising predictions. The prediction is also performed for an ambient response input with multiple frequencies. Moreover, the trained ANN for aerodynamic forcing is coupled with the structural model to perform fully-coupled fluid--structure interaction analysis to determine the aeroelastic instability limit. The sensitivity of the ANN parameters to the model prediction quality and the efficiency has also been highlighted. The proposed methodology has wide application in the analysis and design of long-span bridges.},
  subject      = {Aerodynamik},
  language  = {en}
}
@article{AbbaspourGilandehMolaeeSabzietal.,
  author    = {Abbaspour-Gilandeh, Yousef and Molaee, Amir and Sabzi, Sajad and Nabipour, Narjes and Shamshirband, Shahaboddin and Mosavi, Amir},
  title     = {A Combined Method of Image Processing and Artificial Neural Network for the Identification of 13 Iranian Rice Cultivars},
  series = {agronomy},
  volume    = {2020},
  journal   = {agronomy},
  number    = {Volume 10, Issue 1, 117},
  publisher = {MDPI},
  doi       = {10.3390/agronomy10010117},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200123-40695},
  pages     = {21},
  abstract  = {Due to the importance of identifying crop cultivars, the advancement of accurate assessment of cultivars is considered essential. The existing methods for identifying rice cultivars are mainly time-consuming, costly, and destructive. Therefore, the development of novel methods is highly beneficial. The aim of the present research is to classify common rice cultivars in Iran based on color, morphologic, and texture properties using artificial intelligence (AI) methods. In doing so, digital images of 13 rice cultivars in Iran in three forms of paddy, brown, and white are analyzed through pre-processing and segmentation of using MATLAB. Ninety-two specificities, including 60 color, 14 morphologic, and 18 texture properties, were identified for each rice cultivar. In the next step, the normal distribution of data was evaluated, and the possibility of observing a significant difference between all specificities of cultivars was studied using variance analysis. In addition, the least significant difference (LSD) test was performed to obtain a more accurate comparison between cultivars. To reduce data dimensions and focus on the most effective components, principal component analysis (PCA) was employed. Accordingly, the accuracy of rice cultivar separations was calculated for paddy, brown rice, and white rice using discriminant analysis (DA), which was 89.2\%, 87.7\%, and 83.1\%, respectively. To identify and classify the desired cultivars, a multilayered perceptron neural network was implemented based on the most effective components. The results showed 100\% accuracy of the network in identifying and classifying all mentioned rice cultivars. Hence, it is concluded that the integrated method of image processing and pattern recognition methods, such as statistical classification and artificial neural networks, can be used for identifying and classification of rice cultivars.},
  subject      = {Maschinelles Lernen},
  language  = {en}
}
@article{AbdelnourZabel,
  author    = {Abdelnour, Mena and Zabel, Volkmar},
  title     = {Modal identification of structures with a dynamic behaviour characterised by global and local modes at close frequencies},
  series = {Acta Mechanica},
  volume    = {2023},
  journal   = {Acta Mechanica},
  publisher = {Springer},
  address   = {Wien},
  doi       = {10.1007/s00707-023-03598-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230525-63822},
  pages     = {1 -- 21},
  abstract  = {Identification of modal parameters of a space frame structure is a complex assignment due to a large number of degrees of freedom, close natural frequencies, and different vibrating mechanisms. Research has been carried out on the modal identification of rather simple truss structures. So far, less attention has been given to complex three-dimensional truss structures. This work develops a vibration-based methodology for determining modal information of three-dimensional space truss structures. The method uses a relatively complex space truss structure for its verification. Numerical modelling of the system gives modal information about the expected vibration behaviour. The identification process involves closely spaced modes that are characterised by local and global vibration mechanisms. To distinguish between local and global vibrations of the system, modal strain energies are used as an indicator. The experimental validation, which incorporated a modal analysis employing the stochastic subspace identification method, has confirmed that considering relatively high model orders is required to identify specific mode shapes. Especially in the case of the determination of local deformation modes of space truss members, higher model orders have to be taken into account than in the modal identification of most other types of structures.},
  subject      = {Fachwerkbau},
  language  = {en}
}
@phdthesis{Abeltshauser,
  author    = {Abeltshauser, Rainer},
  title     = {Identification and separation of physical effects of coupled systems by using defined model abstractions},
  doi       = {10.25643/bauhaus-universitaet.2860},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28600},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {The thesis investigates at the computer aided simulation process for operational vibration analysis of complex coupled systems. As part of the internal methods project "Absolute Values" of the BMW Group, the thesis deals with the analysis of the structural dynamic interactions and excitation interactions. The overarching aim of the methods project is to predict the operational vibrations of engines. Simulations are usually used to analyze technical aspects (e. g. operational vibrations, strength, ...) of single components in the industrial development. The boundary conditions of submodels are mostly based on experiences. So the interactions with neighboring components and systems are neglected. To get physically more realistic results but still efficient simulations, this work wants to support the engineer during the preprocessing phase by useful criteria. At first suitable abstraction levels based on the existing literature are defined to identify structural dynamic interactions and excitation interactions of coupled systems. So it is possible to separate different effects of the coupled subsystems. On this basis, criteria are derived to assess the influence of interactions between the considered systems. These criteria can be used during the preprocessing phase and help the engineer to build up efficient models with respect to the interactions with neighboring systems. The method was developed by using several models with different complexity levels. Furthermore, the method is proved for the application in the industrial environment by using the example of a current combustion engine.},
  subject      = {Strukturdynamik},
  language  = {en}
}
@phdthesis{AbuBakar,
  author    = {Abu Bakar, Ilyani Akmar},
  title     = {Computational Analysis of Woven Fabric Composites: Single- and Multi-Objective Optimizations and Sensitivity Analysis in Meso-scale Structures},
  issn      = {1610-7381},
  doi       = {10.25643/bauhaus-universitaet.4176},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200605-41762},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {151},
  abstract  = {This study permits a reliability analysis to solve the mechanical behaviour issues existing in the current structural design of fabric structures. Purely predictive material models are highly desirable to facilitate an optimized design scheme and to significantly reduce time and cost at the design stage, such as experimental characterization. The present study examined the role of three major tasks; a) single-objective optimization, b) sensitivity analyses and c) multi-objective optimization on proposed weave structures for woven fabric composites. For single-objective optimization task, the first goal is to optimize the elastic properties of proposed complex weave structure under unit cells basis based on periodic boundary conditions. We predict the geometric characteristics towards skewness of woven fabric composites via Evolutionary Algorithm (EA) and a parametric study. We also demonstrate the effect of complex weave structures on the fray tendency in woven fabric composites via tightness evaluation. We utilize a procedure which does not require a numerical averaging process for evaluating the elastic properties of woven fabric composites. The fray tendency and skewness of woven fabrics depends upon the behaviour of the floats which is related to the factor of weave. Results of this study may suggest a broader view for further research into the effects of complex weave structures or may provide an alternative to the fray and skewness problems of current weave structure in woven fabric composites. A comprehensive study is developed on the complex weave structure model which adopts the dry woven fabric of the most potential pattern in singleobjective optimization incorporating the uncertainties parameters of woven fabric composites. The comprehensive study covers the regression-based and variance-based sensitivity analyses. The second task goal is to introduce the fabric uncertainties parameters and elaborate how they can be incorporated into finite element models on macroscopic material parameters such as elastic modulus and shear modulus of dry woven fabric subjected to uni-axial and biaxial deformations. Significant correlations in the study, would indicate the need for a thorough investigation of woven fabric composites under uncertainties parameters. The study describes here could serve as an alternative to identify effective material properties without prolonged time consumption and expensive experimental tests. The last part focuses on a hierarchical stochastic multi-scale optimization approach (fine-scale and coarse-scale optimizations) under geometrical uncertainties parameters for hybrid composites considering complex weave structure. The fine-scale optimization is to determine the best lamina pattern that maximizes its macroscopic elastic properties, conducted by EA under the following uncertain mesoscopic parameters: yarn spacing, yarn height, yarn width and misalignment of yarn angle. The coarse-scale optimization has been carried out to optimize the stacking sequences of symmetric hybrid laminated composite plate with uncertain mesoscopic parameters by employing the Ant Colony Algorithm (ACO). The objective functions of the coarse-scale optimization are to minimize the cost (C) and weight (W) of the hybrid laminated composite plate considering the fundamental frequency and the buckling load factor as the design constraints. Based on the uncertainty criteria of the design parameters, the appropriate variation required for the structural design standards can be evaluated using the reliability tool, and then an optimized design decision in consideration of cost can be subsequently determined.},
  subject      = {Verbundwerkstoff},
  language  = {en}
}
@article{AchenbachLahmerMorgenthal,
  author    = {Achenbach, Marcus and Lahmer, Tom and Morgenthal, Guido},
  title     = {Global Sensitivity Analysis of Reinforced Concrete Walls Subjected to Standard Fire - A Comparison of Methods},
  series = {14th International Probabilistic Workshop},
  journal   = {14th International Probabilistic Workshop},
  pages     = {97 -- 106},
  abstract  = {Global Sensitivity Analysis of Reinforced Concrete Walls Subjected to Standard Fire—A Comparison of Methods},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@phdthesis{Ahmad,
  author    = {Ahmad, Sofyan},
  title     = {Reference Surface-Based System Identification},
  doi       = {10.25643/bauhaus-universitaet.2113},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20140205-21132},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {153},
  abstract  = {Environmental and operational variables and their impact on structural responses have been acknowledged as one of the most important challenges for the application of the ambient vibration-based damage identification in structures. The damage detection procedures may yield poor results, if the impacts of loading and environmental conditions of the structures are not considered. The reference-surface-based method, which is proposed in this thesis, is addressed to overcome this problem. In the proposed method, meta-models are used to take into account significant effects of the environmental and operational variables. The usage of the approximation models, allows the proposed method to simply handle multiple non-damaged variable effects simultaneously, which for other methods seems to be very complex. The input of the meta-model are the multiple non-damaged variables while the output is a damage indicator. The reference-surface-based method diminishes the effect of the non-damaged variables to the vibration based damage detection results. Hence, the structure condition that is assessed by using ambient vibration data at any time would be more reliable. Immediate reliable information regarding the structure condition is required to quickly respond to the event, by means to take necessary actions concerning the future use or further investigation of the structures, for instance shortly after extreme events such as earthquakes. The critical part of the proposed damage detection method is the learning phase, where the meta-models are trained by using input-output relation of observation data. Significant problems that may encounter during the learning phase are outlined and some remedies to overcome the problems are suggested. The proposed damage identification method is applied to numerical and experimental models. In addition to the natural frequencies, wavelet energy and stochastic subspace damage indicators are used.},
  subject      = {System Identification},
  language  = {en}
}
@inproceedings{AhmadZabelKoenke,
  author    = {Ahmad, Sofyan and Zabel, Volkmar and K{\"o}nke, Carsten},
  title     = {WAVELET-BASED INDICATORS FOR RESPONSE SURFACE MODELS IN DAMAGE IDENTIFICATION OF STRUCTURES},
  series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar},
  booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar},
  organization    = {Bauhaus-Universit{\"a}t Weimar},
  issn      = {1611-4086},
  doi       = {10.25643/bauhaus-universitaet.2758},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170306-27588},
  pages     = {14},
  abstract  = {In this paper, wavelet energy damage indicator is used in response surface methodology to identify the damage in simulated filler beam railway bridge. The approximate model is addressed to include the operational and surrounding condition in the assessment. The procedure is split into two stages, the training and detecting phase. During training phase, a so-called response surface is built from training data using polynomial regression and radial basis function approximation approaches. The response surface is used to detect the damage in structure during detection phase. The results show that the response surface model is able to detect moderate damage in one of bridge supports while the temperatures and train velocities are varied.},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AhmadiBaghbanSadeghzadehetal.,
  author    = {Ahmadi, Mohammad Hossein and Baghban, Alireza and Sadeghzadeh, Milad and Zamen, Mohammad and Mosavi, Amir and Shamshirband, Shahaboddin and Kumar, Ravinder and Mohammadi-Khanaposhtani, Mohammad},
  title     = {Evaluation of electrical efficiency of photovoltaic thermal solar collector},
  series = {Engineering Applications of Computational Fluid Mechanics},
  volume    = {2020},
  journal   = {Engineering Applications of Computational Fluid Mechanics},
  number    = {volume 14, issue 1},
  publisher = {Taylor \& Francis},
  doi       = {10.1080/19942060.2020.1734094},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200304-41049},
  pages     = {545 -- 565},
  abstract  = {In this study, machine learning methods of artificial neural networks (ANNs), least squares support vector machines (LSSVM), and neuro-fuzzy are used for advancing prediction models for thermal performance of a photovoltaic-thermal solar collector (PV/T). In the proposed models, the inlet temperature, flow rate, heat, solar radiation, and the sun heat have been considered as the input variables. Data set has been extracted through experimental measurements from a novel solar collector system. Different analyses are performed to examine the credibility of the introduced models and evaluate their performances. The proposed LSSVM model outperformed the ANFIS and ANNs models. LSSVM model is reported suitable when the laboratory measurements are costly and time-consuming, or achieving such values requires sophisticated interpretations.},
  subject      = {Fotovoltaik},
  language  = {en}
}
@article{AlYasiriMutasharGuerlebecketal.,
  author    = {Al-Yasiri, Zainab Riyadh Shaker and Mutashar, Hayder Majid and G{\"u}rlebeck, Klaus and Lahmer, Tom},
  title     = {Damage Sensitive Signals for the Assessment of the Conditions of Wind Turbine Rotor Blades Using Electromagnetic Waves},
  series = {Infrastructures},
  volume    = {2022},
  journal   = {Infrastructures},
  number    = {Volume 7, Issue 8 (August 2022), article 104},
  editor    = {Shafiullah, GM},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/infrastructures7080104},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20220831-47093},
  pages     = {18},
  abstract  = {One of the most important renewable energy technologies used nowadays are wind power turbines. In this paper, we are interested in identifying the operating status of wind turbines, especially rotor blades, by means of multiphysical models. It is a state-of-the-art technology to test mechanical structures with ultrasonic-based methods. However, due to the density and the required high resolution, the testing is performed with high-frequency waves, which cannot penetrate the structure in depth. Therefore, there is a need to adopt techniques in the fields of multiphysical model-based inversion schemes or data-driven structural health monitoring. Before investing effort in the development of such approaches, further insights and approaches are necessary to make the techniques applicable to structures such as wind power plants (blades). Among the expected developments, further accelerations of the so-called "forward codes" for a more efficient implementation of the wave equation could be envisaged. Here, we employ electromagnetic waves for the early detection of cracks. Because in many practical situations, it is not possible to apply techniques from tomography (characterized by multiple sources and sensor pairs), we focus here on the question of whether the existence of cracks can be determined by using only one source for the sent waves.},
  subject      = {Windkraftwerk},
  language  = {en}
}
@phdthesis{Alalade,
  author    = {Alalade, Muyiwa},
  title     = {An Enhanced Full Waveform Inversion Method for the Structural Analysis of Dams},
  doi       = {10.25643/bauhaus-universitaet.3956},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20190813-39566},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {Since the Industrial Revolution in the 1700s, the high emission of gaseous wastes into the atmosphere from the usage of fossil fuels has caused a general increase in temperatures globally. To combat the environmental imbalance, there is an increase in the demand for renewable energy sources. Dams play a major role in the generation of "green" energy. However, these structures require frequent and strict monitoring to ensure safe and efficient operation. To tackle the challenges faced in the application of convention dam monitoring techniques, this work proposes the inverse analysis of numerical models to identify damaged regions in the dam. Using a dynamic coupled hydro-mechanical Extended Finite Element Method (XFEM) model and a global optimization strategy, damage (crack) in the dam is identified. By employing seismic waves to probe the dam structure, a more detailed information on the distribution of heterogeneous materials and damaged regions are obtained by the application of the Full Waveform Inversion (FWI) method. The FWI is based on a local optimization strategy and thus it is highly dependent on the starting model. A variety of data acquisition setups are investigated, and an optimal setup is proposed. The effect of different starting models and noise in the measured data on the damage identification is considered. Combining the non-dependence of a starting model of the global optimization strategy based dynamic coupled hydro-mechanical XFEM method and the detailed output of the local optimization strategy based FWI method, an enhanced Full Waveform Inversion is proposed for the structural analysis of dams.},
  subject      = {Talsperre},
  language  = {en}
}
@article{AlaladeReichertKoehnetal.,
  author    = {Alalade, Muyiwa and Reichert, Ina and K{\"o}hn, Daniel and Wuttke, Frank and Lahmer, Tom},
  title     = {A Cyclic Multi-Stage Implementation of the Full-Waveform Inversion for the Identification of Anomalies in Dams},
  series = {Infrastructures},
  volume    = {2022},
  journal   = {Infrastructures},
  number    = {Volume 7, issue 12, article 161},
  editor    = {Qu, Chunxu and Gao, Chunxu and Zhang, Rui and Jia, Ziguang and Li, Jiaxiang},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/infrastructures7120161},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20221201-48396},
  pages     = {19},
  abstract  = {For the safe and efficient operation of dams, frequent monitoring and maintenance are required. These are usually expensive, time consuming, and cumbersome. To alleviate these issues, we propose applying a wave-based scheme for the location and quantification of damages in dams. To obtain high-resolution "interpretable" images of the damaged regions, we drew inspiration from non-linear full-multigrid methods for inverse problems and applied a new cyclic multi-stage full-waveform inversion (FWI) scheme. Our approach is less susceptible to the stability issues faced by the standard FWI scheme when dealing with ill-posed problems. In this paper, we first selected an optimal acquisition setup and then applied synthetic data to demonstrate the capability of our approach in identifying a series of anomalies in dams by a mixture of reflection and transmission tomography. The results had sufficient robustness, showing the prospects of application in the field of non-destructive testing of dams.},
  subject      = {Damm},
  language  = {en}
}
@article{AlemuHabteLahmeretal.,
  author    = {Alemu, Yohannes L. and Habte, Bedilu and Lahmer, Tom and Urgessa, Girum},
  title     = {Topologically preoptimized ground structure (TPOGS) for the optimization of 3D RC buildings},
  series = {Asian Journal of Civil Engineering},
  volume    = {2023},
  journal   = {Asian Journal of Civil Engineering},
  publisher = {Springer International Publishing},
  address   = {Cham},
  doi       = {10.1007/s42107-023-00640-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20230517-63677},
  pages     = {1 -- 11},
  abstract  = {As an optimization that starts from a randomly selected structure generally does not guarantee reasonable optimality, the use of a systemic approach, named the ground structure, is widely accepted in steel-made truss and frame structural design. However, in the case of reinforced concrete (RC) structural optimization, because of the orthogonal orientation of structural members, randomly chosen or architect-sketched framing is used. Such a one-time fixed layout trend, in addition to its lack of a systemic approach, does not necessarily guarantee optimality. In this study, an approach for generating a candidate ground structure to be used for cost or weight minimization of 3D RC building structures with included slabs is developed. A multiobjective function at the floor optimization stage and a single objective function at the frame optimization stage are considered. A particle swarm optimization (PSO) method is employed for selecting the optimal ground structure. This method enables generating a simple, yet potential, real-world representation of topologically preoptimized ground structure while both structural and main architectural requirements are considered. This is supported by a case study for different floor domain sizes.},
  subject      = {Bodenmechanik},
  language  = {en}
}
@phdthesis{Alkam,
  author    = {Alkam, Feras},
  title     = {Vibration-based Monitoring of Concrete Catenary Poles using Bayesian Inference},
  volume    = {2021},
  publisher = {Bauhaus-Universit{\"a}tsverlag},
  address   = {Weimar},
  doi       = {10.25643/bauhaus-universitaet.4433},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210526-44338},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {177},
  abstract  = {This work presents a robust status monitoring approach for detecting damage in cantilever structures based on logistic functions. Also, a stochastic damage identification approach based on changes of eigenfrequencies is proposed. The proposed algorithms are verified using catenary poles of electrified railways track. The proposed damage features overcome the limitation of frequency-based damage identification methods available in the literature, which are valid to detect damage in structures to Level 1 only. Changes in eigenfrequencies of cantilever structures are enough to identify possible local damage at Level 3, i.e., to cover damage detection, localization, and quantification. The proposed algorithms identified the damage with relatively small errors, even at a high noise level.},
  subject      = {Parameteridentifikation},
  language  = {en}
}
@article{AlkamLahmer,
  author    = {Alkam, Feras and Lahmer, Tom},
  title     = {A robust method of the status monitoring of catenary poles installed along high-speed electrified train tracks},
  series = {Results in Engineering},
  volume    = {2021},
  journal   = {Results in Engineering},
  number    = {volume 12, article 100289},
  publisher = {Elsevier},
  address   = {Amsterdam},
  doi       = {10.1016/j.rineng.2021.100289},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20211011-45212},
  pages     = {1 -- 8},
  abstract  = {Electric trains are considered one of the most eco-friendly and safest means of transportation. Catenary poles are used worldwide to support overhead power lines for electric trains. The performance of the catenary poles has an extensive influence on the integrity of the train systems and, consequently, the connected human services. It became a must nowadays to develop SHM systems that provide the instantaneous status of catenary poles in- service, making the decision-making processes to keep or repair the damaged poles more feasible. This study develops a data-driven, model-free approach for status monitoring of cantilever structures, focusing on pre-stressed, spun-cast ultrahigh-strength concrete catenary poles installed along high-speed train tracks. The pro-posed approach evaluates multiple damage features in an unfied damage index, which leads to straightforward interpretation and comparison of the output. Besides, it distinguishes between multiple damage scenarios of the poles, either the ones caused by material degradation of the concrete or by the cracks that can be propagated during the life span of the given structure. Moreover, using a logistic function to classify the integrity of structure avoids the expensive learning step in the existing damage detection approaches, namely, using the modern machine and deep learning methods. The findings of this study look very promising when applied to other types of cantilever structures, such as the poles that support the power transmission lines, antenna masts, chimneys, and wind turbines.},
  subject      = {Fahrleitung},
  language  = {en}
}
@article{AlkamLahmer,
  author    = {Alkam, Feras and Lahmer, Tom},
  title     = {Eigenfrequency-Based Bayesian Approach for Damage Identification in Catenary Poles},
  series = {Infrastructures},
  volume    = {2021},
  journal   = {Infrastructures},
  number    = {Volume 6, issue 4, article 57},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/infrastructures6040057},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210510-44256},
  pages     = {1 -- 19},
  abstract  = {This study proposes an efficient Bayesian, frequency-based damage identification approach to identify damages in cantilever structures with an acceptable error rate, even at high noise levels. The catenary poles of electric high-speed train systems were selected as a realistic case study to cover the objectives of this study. Compared to other frequency-based damage detection approaches described in the literature, the proposed approach is efficiently able to detect damages in cantilever structures to higher levels of damage detection, namely identifying both the damage location and severity using a low-cost structural health monitoring (SHM) system with a limited number of sensors; for example, accelerometers. The integration of Bayesian inference, as a stochastic framework, in the proposed approach, makes it possible to utilize the benefit of data fusion in merging the informative data from multiple damage features, which increases the quality and accuracy of the results. The findings provide the decision-maker with the information required to manage the maintenance, repair, or replacement procedures.},
  subject      = {Fahrleitung},
  language  = {en}
}
@misc{Almasi,
  type      = {Master Thesis},
  author    = {Almasi, Ashkan},
  title     = {Stochastic Analysis of Interfacial Effects on the Polymeric Nanocomposites},
  doi       = {10.25643/bauhaus-universitaet.2433},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150709-24339},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {The polymeric clay nanocomposites are a new class of materials of which recently have become the centre of attention due to their superior mechanical and physical properties. Several studies have been performed on the mechanical characterisation of these nanocomposites; however most of those studies have neglected the effect of the interfacial region between the clays and the matrix despite of its significant influence on the mechanical performance of the nanocomposites. There are different analytical methods to calculate the overall elastic material properties of the composites. In this study we use the Mori-Tanaka method to determine the overall stiffness of the composites for simple inclusion geometries of cylinder and sphere. Furthermore, the effect of interphase layer on the overall properties of composites is calculated. Here, we intend to get ounds for the effective mechanical properties to compare with the analytical results. Hence, we use linear displacement boundary conditions (LD) and uniform traction boundary conditions (UT) accordingly. Finally, the analytical results are compared with numerical results and they are in a good agreement. The next focus of this dissertation is a computational approach with a hierarchical multiscale method on the mesoscopic level. In other words, in this study we use the stochastic analysis and computational homogenization method to analyse the effect of thickness and stiffness of the interfacial region on the overall elastic properties of the clay/epoxy nanocomposites. The results show that the increase in interphase thickness, reduces the stiffness of the clay/epoxy naocomposites and this decrease becomes significant in higher clay contents. The results of the sensitivity analysis prove that the stiffness of the interphase layer has more significant effect on the final stiffness of nanocomposites. We also validate the results with the available experimental results from the literature which show good agreement.},
  language  = {en}
}
@article{AmaniBagherzadehRabczuk,
  author    = {Amani, Jafar and Bagherzadeh, Amir Saboor and Rabczuk, Timon},
  title     = {Error estimate and adaptive refinement in Mixed Discrete Least Squares Meshless method},
  series = {Mathematical Problems in Engineering},
  journal   = {Mathematical Problems in Engineering},
  abstract  = {Error estimate and adaptive refinement in Mixed Discrete Least Squares Meshless method},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AmaniSaboorBagherzadehRabczuk,
  author    = {Amani, Jafar and Saboor Bagherzadeh, Amir and Rabczuk, Timon},
  title     = {Error estimate and adaptive refinement in mixed discrete least squares meshless method},
  series = {Mathematical Problems in Engineering},
  journal   = {Mathematical Problems in Engineering},
  doi       = {10.1155/2014/721240},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170413-31181},
  abstract  = {The node moving and multistage node enrichment adaptive refinement procedures are extended in mixed discrete least squares meshless (MDLSM) method for efficient analysis of elasticity problems. In the formulation of MDLSM method, mixed formulation is accepted to avoid second-order differentiation of shape functions and to obtain displacements and stresses simultaneously. In the refinement procedures, a robust error estimator based on the value of the least square residuals functional of the governing differential equations and its boundaries at nodal points is used which is inherently available from the MDLSM formulation and can efficiently identify the zones with higher numerical errors. The results are compared with the refinement procedures in the irreducible formulation of discrete least squares meshless (DLSM) method and show the accuracy and efficiency of the proposed procedures. Also, the comparison of the error norms and convergence rate show the fidelity of the proposed adaptive refinement procedures in the MDLSM method.},
  subject      = {Elastizit{\"a}t},
  language  = {en}
}
@phdthesis{Amiri,
  author    = {Amiri, Fatemeh},
  title     = {Computational modelling of fracture with local maximum entropy approximations},
  doi       = {10.25643/bauhaus-universitaet.2631},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20160719-26310},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {130},
  abstract  = {The key objective of this research is to study fracture with a meshfree method, local maximum entropy approximations, and model fracture in thin shell structures with complex geometry and topology. This topic is of high relevance for real-world applications, for example in the automotive industry and in aerospace engineering. The shell structure can be described efficiently by meshless methods which are capable of describing complex shapes as a collection of points instead of a structured mesh. In order to find the appropriate numerical method to achieve this goal, the first part of the work was development of a method based on local maximum entropy (LME) shape functions together with enrichment functions used in partition of unity methods to discretize problems in linear elastic fracture mechanics. We obtain improved accuracy relative to the standard extended finite element method (XFEM) at a comparable computational cost. In addition, we keep the advantages of the LME shape functions,such as smoothness and non-negativity. We show numerically that optimal convergence (same as in FEM) for energy norm and stress intensity factors can be obtained through the use of geometric (fixed area) enrichment with no special treatment of the nodes near the crack such as blending or shifting. As extension of this method to three dimensional problems and complex thin shell structures with arbitrary crack growth is cumbersome, we developed a phase field model for fracture using LME. Phase field models provide a powerful tool to tackle moving interface problems, and have been extensively used in physics and materials science. Phase methods are gaining popularity in a wide set of applications in applied science and engineering, recently a second order phase field approximation for brittle fracture has gathered significant interest in computational fracture such that sharp cracks discontinuities are modeled by a diffusive crack. By minimizing the system energy with respect to the mechanical displacements and the phase-field, subject to an irreversibility condition to avoid crack healing, this model can describe crack nucleation, propagation, branching and merging. One of the main advantages of the phase field modeling of fractures is the unified treatment of the interfacial tracking and mechanics, which potentially leads to simple, robust, scalable computer codes applicable to complex systems. In other words, this approximation reduces considerably the implementation complexity because the numerical tracking of the fracture is not needed, at the expense of a high computational cost. We present a fourth-order phase field model for fracture based on local maximum entropy (LME) approximations. The higher order continuity of the meshfree LME approximation allows to directly solve the fourth-order phase field equations without splitting the fourth-order differential equation into two second order differential equations. Notably, in contrast to previous discretizations that use at least a quadratic basis, only linear completeness is needed in the LME approximation. We show that the crack surface can be captured more accurately in the fourth-order model than the second-order model. Furthermore, less nodes are needed for the fourth-order model to resolve the crack path. Finally, we demonstrate the performance of the proposed meshfree fourth order phase-field formulation for 5 representative numerical examples. Computational results will be compared to analytical solutions within linear elastic fracture mechanics and experimental data for three-dimensional crack propagation. In the last part of this research, we present a phase-field model for fracture in Kirchoff-Love thin shells using the local maximum-entropy (LME) meshfree method. Since the crack is a natural outcome of the analysis it does not require an explicit representation and tracking, which is advantageous over techniques as the extended finite element method that requires tracking of the crack paths. The geometric description of the shell is based on statistical learning techniques that allow dealing with general point set surfaces avoiding a global parametrization, which can be applied to tackle surfaces of complex geometry and topology. We show the flexibility and robustness of the present methodology for two examples: plate in tension and a set of open connected pipes.},
  language  = {en}
}
@article{AmiriMillanShenetal.,
  author    = {Amiri, Fatemeh and Mill{\´a}n, D. and Shen, Y. and Rabczuk, Timon and Arroyo, M.},
  title     = {Phase-field modeling of fracture in linear thin shells},
  series = {Theoretical and Applied Fracture Mechanics},
  journal   = {Theoretical and Applied Fracture Mechanics},
  pages     = {102 -- 109},
  abstract  = {Phase-field modeling of fracture in linear thin shells},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AmirinasabShamshirbandChronopoulosetal.,
  author    = {Amirinasab, Mehdi and Shamshirband, Shahaboddin and Chronopoulos, Anthony Theodore and Mosavi, Amir and Nabipour, Narjes},
  title     = {Energy-Efficient Method for Wireless Sensor Networks Low-Power Radio Operation in Internet of Things},
  series = {electronics},
  volume    = {2020},
  journal   = {electronics},
  number    = {volume 9, issue 2, 320},
  publisher = {MDPI},
  doi       = {10.3390/electronics9020320},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20200213-40954},
  pages     = {20},
  abstract  = {The radio operation in wireless sensor networks (WSN) in Internet of Things (IoT)applications is the most common source for power consumption. Consequently, recognizing and controlling the factors affecting radio operation can be valuable for managing the node power consumption. Among essential factors affecting radio operation, the time spent for checking the radio is of utmost importance for monitoring power consumption. It can lead to false WakeUp or idle listening in radio duty cycles and ContikiMAC. ContikiMAC is a low-power radio duty-cycle protocol in Contiki OS used in WakeUp mode, as a clear channel assessment (CCA) for checking radio status periodically. This paper presents a detailed analysis of radio WakeUp time factors of ContikiMAC. Furthermore, we propose a lightweight CCA (LW-CCA) as an extension to ContikiMAC to reduce the Radio Duty-Cycles in false WakeUps and idle listening though using dynamic received signal strength indicator (RSSI) status check time. The simulation results in the Cooja simulator show that LW-CCA reduces about 8\% energy consumption in nodes while maintaining up to 99\% of the packet delivery rate (PDR).},
  subject      = {Internet der Dinge},
  language  = {en}
}
@article{AnitescuJiaZhangetal.,
  author    = {Anitescu, Cosmin and Jia, Yue and Zhang, Yongjie and Rabczuk, Timon},
  title     = {An isogeometric collocation method using superconvergent points},
  series = {Computer Methods in Applied Mechanics and Engineer-ing},
  journal   = {Computer Methods in Applied Mechanics and Engineer-ing},
  pages     = {1073 -- 1097},
  abstract  = {An isogeometric collocation method using superconvergent points},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{ArashRabczukJiang,
  author    = {Arash, Behrouz and Rabczuk, Timon and Jiang, Jin-Wu},
  title     = {Nanoresonators and their applications: a state of the art review},
  series = {Applied Physics Reviews},
  journal   = {Applied Physics Reviews},
  abstract  = {Nanoresonators and their applications: a state of the art review},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasPintodaCostaRabczuketal.,
  author    = {Areias, Pedro and Pinto da Costa, A. and Rabczuk, Timon and Queiros de Melo, F. J. M. and Dias-da-Costa, D.},
  title     = {An alternative formulation for quasi-static frictional and cohesive contact problems},
  series = {Computational Mechanics},
  journal   = {Computational Mechanics},
  pages     = {807 -- 824},
  abstract  = {An alternative formulation for quasi-static frictional and cohesive contact problems},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczuk,
  author    = {Areias, Pedro and Rabczuk, Timon},
  title     = {Finite strain fracture of plates and shells with configurational forces and edge rotation},
  series = {International Journal for Numerical Methods in Engineering},
  journal   = {International Journal for Numerical Methods in Engineering},
  abstract  = {Finite strain fracture of plates and shells with configurational forces and edge rotation},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukBarbosa,
  author    = {Areias, Pedro and Rabczuk, Timon and Barbosa, J.I.},
  title     = {The extended unsymmetric frontal solution for multiple-point constraints},
  series = {Engineering Computations},
  journal   = {Engineering Computations},
  abstract  = {The extended unsymmetric frontal solution for multiple-point constraints},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukCamanho,
  author    = {Areias, Pedro and Rabczuk, Timon and Camanho, P.P.},
  title     = {Finite strain fracture of 2D problems with injected anisotropic softening elements},
  series = {Theoretical and Applied Fracture Mechanics},
  journal   = {Theoretical and Applied Fracture Mechanics},
  abstract  = {Finite strain fracture of 2D problems with injected anisotropic softening elements},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukCesardeSaetal.,
  author    = {Areias, Pedro and Rabczuk, Timon and Cesar de Sa, J.M. and Garcao, J.E.},
  title     = {Finite strain quadrilateral shell using least-squares _t of relative Lagrangian in-plane strains},
  series = {Finite Elements in Analysis and Design},
  journal   = {Finite Elements in Analysis and Design},
  pages     = {26 -- 40},
  abstract  = {Finite strain quadrilateral shell using least-squares _t of relative Lagrangian in-plane strains},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukCesardeSaetal.,
  author    = {Areias, Pedro and Rabczuk, Timon and Cesar de Sa, J.M. and Jorge, R.N.},
  title     = {A semi-implicit _nite strain shell algorithm using in-plane strains based on least-squares},
  series = {Computational Mechanics},
  journal   = {Computational Mechanics},
  abstract  = {A semi-implicit _nite strain shell algorithm using in-plane strains based on least-squares},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukDiasdaCosta,
  author    = {Areias, Pedro and Rabczuk, Timon and Dias-da-Costa, D.},
  title     = {Assumed-metric spherically-interpolated quadrilateral shell element},
  series = {Finite Elements in Analysis and Design},
  journal   = {Finite Elements in Analysis and Design},
  pages     = {53 -- 67},
  abstract  = {Assumed-metric spherically-interpolated quadrilateral shell element},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukDiasdaCosta,
  author    = {Areias, Pedro and Rabczuk, Timon and Dias-da-Costa, D.},
  title     = {Asymmetric Shell Elements Based on a Corrected Updated-Lagrangian Approach},
  series = {CMES: Computer Modeling in Engineering and Sciences},
  journal   = {CMES: Computer Modeling in Engineering and Sciences},
  abstract  = {Asymmetric Shell Elements Based on a Corrected Updated-Lagrangian Approach},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukDiasdaCostaetal.,
  author    = {Areias, Pedro and Rabczuk, Timon and Dias-da-Costa, D. and Piresh, E.B.},
  title     = {Implicit solutions with consistent additive and multiplicative components},
  series = {Finite Elements in Analysis and Design},
  journal   = {Finite Elements in Analysis and Design},
  doi       = {10.1016/j.finel.2012.03.007},
  pages     = {15 -- 31},
  abstract  = {This work describes an algorithm and corresponding software for incorporating general nonlinear multiple-point equality constraints in a implicit sparse direct solver. It is shown that direct addressing of sparse matrices is possible in general circumstances, circumventing the traditional linear or binary search for introducing (generalized) constituents to a sparse matrix. Nested and arbitrarily interconnected multiple-point constraints are introduced by processing of multiplicative constituents with a built-in topological ordering of the resulting directed graph. A classification of discretization methods is performed and some re-classified problems are described and solved under this proposed perspective. The dependence relations between solution methods, algorithms and constituents becomes apparent. Fracture algorithms can be naturally casted in this framework. Solutions based on control equations are also directly incorporated as equality constraints. We show that arbitrary constituents can be used as long as the resulting directed graph is acyclic. It is also shown that graph partitions and orderings should be performed in the innermost part of the algorithm, a fact with some peculiar consequences. The core of our implicit code is described, specifically new algorithms for direct access of sparse matrices (by means of the clique structure) and general constituent processing. It is demonstrated that the graph structure of the second derivatives of the equality constraints are cliques (or pseudo-elements) and are naturally included as such. A complete algorithm is presented which allows a complete automation of equality constraints, avoiding the need of pre-sorting. Verification applications in four distinct areas are shown: single and multiple rigid body dynamics, solution control and computational fracture.},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{AreiasRabczukQueirosdeMeloetal.,
  author    = {Areias, Pedro and Rabczuk, Timon and Queiros de Melo, F. J. M. and Cesar de Sa, J.M.},
  title     = {Coulomb frictional contact by explicit projection in the cone for _nite displacement quasi-static problems},
  series = {Computational Mechanics},
  journal   = {Computational Mechanics},
  pages     = {57 -- 72},
  abstract  = {Coulomb frictional contact by explicit projection in the cone for _nite displacement quasi-static problems},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{BakarKramerBordasetal.,
  author    = {Bakar, I. and Kramer, O. and Bordas, St{\´e}phane Pierre Alain and Rabczuk, Timon},
  title     = {Optimization of Elastic Properties and Weaving Patterns of Woven Composites},
  series = {Composite Structures},
  journal   = {Composite Structures},
  pages     = {575 -- 591},
  abstract  = {Optimization of Elastic Properties and Weaving Patterns of Woven Composites},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{BandJanizadehChandraPaletal.,
  author    = {Band, Shahab S. and Janizadeh, Saeid and Chandra Pal, Subodh and Chowdhuri, Indrajit and Siabi, Zhaleh and Norouzi, Akbar and Melesse, Assefa M. and Shokri, Manouchehr and Mosavi, Amir Hosein},
  title     = {Comparative Analysis of Artificial Intelligence Models for Accurate Estimation of Groundwater Nitrate Concentration},
  series = {Sensors},
  volume    = {2020},
  journal   = {Sensors},
  number    = {Volume 20, issue 20, article 5763},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/s20205763},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210122-43364},
  pages     = {1 -- 23},
  abstract  = {Prediction of the groundwater nitrate concentration is of utmost importance for pollution control and water resource management. This research aims to model the spatial groundwater nitrate concentration in the Marvdasht watershed, Iran, based on several artificial intelligence methods of support vector machine (SVM), Cubist, random forest (RF), and Bayesian artificial neural network (Baysia-ANN) machine learning models. For this purpose, 11 independent variables affecting groundwater nitrate changes include elevation, slope, plan curvature, profile curvature, rainfall, piezometric depth, distance from the river, distance from residential, Sodium (Na), Potassium (K), and topographic wetness index (TWI) in the study area were prepared. Nitrate levels were also measured in 67 wells and used as a dependent variable for modeling. Data were divided into two categories of training (70\%) and testing (30\%) for modeling. The evaluation criteria coefficient of determination (R2), mean absolute error (MAE), root mean square error (RMSE), and Nash-Sutcliffe efficiency (NSE) were used to evaluate the performance of the models used. The results of modeling the susceptibility of groundwater nitrate concentration showed that the RF (R2 = 0.89, RMSE = 4.24, NSE = 0.87) model is better than the other Cubist (R2 = 0.87, RMSE = 5.18, NSE = 0.81), SVM (R2 = 0.74, RMSE = 6.07, NSE = 0.74), Bayesian-ANN (R2 = 0.79, RMSE = 5.91, NSE = 0.75) models. The results of groundwater nitrate concentration zoning in the study area showed that the northern parts of the case study have the highest amount of nitrate, which is higher in these agricultural areas than in other areas. The most important cause of nitrate pollution in these areas is agriculture activities and the use of groundwater to irrigate these crops and the wells close to agricultural areas, which has led to the indiscriminate use of chemical fertilizers by irrigation or rainwater of these fertilizers is washed and penetrates groundwater and pollutes the aquifer.},
  subject      = {Grundwasser},
  language  = {en}
}
@article{BandJanizadehChandraPaletal.,
  author    = {Band, Shahab S. and Janizadeh, Saeid and Chandra Pal, Subodh and Saha, Asish and Chakrabortty, Rabbin and Shokri, Manouchehr and Mosavi, Amir Hosein},
  title     = {Novel Ensemble Approach of Deep Learning Neural Network (DLNN) Model and Particle Swarm Optimization (PSO) Algorithm for Prediction of Gully Erosion Susceptibility},
  series = {Sensors},
  volume    = {2020},
  journal   = {Sensors},
  number    = {Volume 20, issue 19, article 5609},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/s20195609},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210122-43341},
  pages     = {1 -- 27},
  abstract  = {This study aims to evaluate a new approach in modeling gully erosion susceptibility (GES) based on a deep learning neural network (DLNN) model and an ensemble particle swarm optimization (PSO) algorithm with DLNN (PSO-DLNN), comparing these approaches with common artificial neural network (ANN) and support vector machine (SVM) models in Shirahan watershed, Iran. For this purpose, 13 independent variables affecting GES in the study area, namely, altitude, slope, aspect, plan curvature, profile curvature, drainage density, distance from a river, land use, soil, lithology, rainfall, stream power index (SPI), and topographic wetness index (TWI), were prepared. A total of 132 gully erosion locations were identified during field visits. To implement the proposed model, the dataset was divided into the two categories of training (70\%) and testing (30\%). The results indicate that the area under the curve (AUC) value from receiver operating characteristic (ROC) considering the testing datasets of PSO-DLNN is 0.89, which indicates superb accuracy. The rest of the models are associated with optimal accuracy and have similar results to the PSO-DLNN model; the AUC values from ROC of DLNN, SVM, and ANN for the testing datasets are 0.87, 0.85, and 0.84, respectively. The efficiency of the proposed model in terms of prediction of GES was increased. Therefore, it can be concluded that the DLNN model and its ensemble with the PSO algorithm can be used as a novel and practical method to predict gully erosion susceptibility, which can help planners and managers to manage and reduce the risk of this phenomenon.},
  subject      = {Geoinformatik},
  language  = {en}
}
@article{BandJanizadehSahaetal.,
  author    = {Band, Shahab S. and Janizadeh, Saeid and Saha, Sunil and Mukherjee, Kaustuv and Khosrobeigi Bozchaloei, Saeid and Cerd{\`a}, Artemi and Shokri, Manouchehr and Mosavi, Amir Hosein},
  title     = {Evaluating the Efficiency of Different Regression, Decision Tree, and Bayesian Machine Learning Algorithms in Spatial Piping Erosion Susceptibility Using ALOS/PALSAR Data},
  series = {Land},
  volume    = {2020},
  journal   = {Land},
  number    = {volume 9, issue 10, article 346},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/land9100346},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20210122-43424},
  pages     = {1 -- 22},
  abstract  = {Piping erosion is one form of water erosion that leads to significant changes in the landscape and environmental degradation. In the present study, we evaluated piping erosion modeling in the Zarandieh watershed of Markazi province in Iran based on random forest (RF), support vector machine (SVM), and Bayesian generalized linear models (Bayesian GLM) machine learning algorithms. For this goal, due to the importance of various geo-environmental and soil properties in the evolution and creation of piping erosion, 18 variables were considered for modeling the piping erosion susceptibility in the Zarandieh watershed. A total of 152 points of piping erosion were recognized in the study area that were divided into training (70\%) and validation (30\%) for modeling. The area under curve (AUC) was used to assess the effeciency of the RF, SVM, and Bayesian GLM. Piping erosion susceptibility results indicated that all three RF, SVM, and Bayesian GLM models had high efficiency in the testing step, such as the AUC shown with values of 0.9 for RF, 0.88 for SVM, and 0.87 for Bayesian GLM. Altitude, pH, and bulk density were the variables that had the greatest influence on the piping erosion susceptibility in the Zarandieh watershed. This result indicates that geo-environmental and soil chemical variables are accountable for the expansion of piping erosion in the Zarandieh watershed.},
  subject      = {Maschinelles Lernen},
  language  = {en}
}
@article{BanihaniRabczukAlmomani,
  author    = {Banihani, Suleiman and Rabczuk, Timon and Almomani, Thakir},
  title     = {POD for real-time simulation of hyperelastic soft biological tissue using the point collocation method of finite spheres},
  series = {Mathematical Problems in Engineering},
  journal   = {Mathematical Problems in Engineering},
  doi       = {10.1155/2013/386501},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170413-31203},
  abstract  = {The point collocation method of finite spheres (PCMFS) is used to model the hyperelastic response of soft biological tissue in real time within the framework of virtual surgery simulation. The proper orthogonal decomposition (POD) model order reduction (MOR) technique was used to achieve reduced-order model of the problem, minimizing computational cost. The PCMFS is a physics-based meshfree numerical technique for real-time simulation of surgical procedures where the approximation functions are applied directly on the strong form of the boundary value problem without the need for integration, increasing computational efficiency. Since computational speed has a significant role in simulation of surgical procedures, the proposed technique was able to model realistic nonlinear behavior of organs in real time. Numerical results are shown to demonstrate the effectiveness of the new methodology through a comparison between full and reduced analyses for several nonlinear problems. It is shown that the proposed technique was able to achieve good agreement with the full model; moreover, the computational and data storage costs were significantly reduced.},
  subject      = {Chirurgie},
  language  = {en}
}
@article{BeexKerfridenRabczuketal.,
  author    = {Beex, L.A.A. and Kerfriden, Pierre and Rabczuk, Timon and Bordas, St{\´e}phane Pierre Alain},
  title     = {Quasicontinuum-based multiscale approaches for plate-like beam lattices experiencing in-plane and out-of-plane deformation},
  series = {Computer Methods in Applied Mechanics and Engineering},
  journal   = {Computer Methods in Applied Mechanics and Engineering},
  abstract  = {Quasicontinuum-based multiscale approaches for plate-like beam lattices experiencing in-plane and out-of-plane deformation},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{BenZhaoZhangetal.,
  author    = {Ben, S. and Zhao, Jun-Hua and Zhang, Yancheng and Rabczuk, Timon},
  title     = {The interface strength and debonding for composite structures: review and recent developments},
  series = {Composite Structures},
  journal   = {Composite Structures},
  abstract  = {The interface strength and debonding for composite structures: review and recent developments},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@phdthesis{Brehm2011,
  author    = {Brehm, Maik},
  title     = {Vibration-based model updating: Reduction and quantification of uncertainties},
  doi       = {10.25643/bauhaus-universitaet.1465},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20110926-15553},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  year      = {2011},
  abstract  = {Numerical models and their combination with advanced solution strategies are standard tools for many engineering disciplines to design or redesign structures and to optimize designs with the purpose to improve specific requirements. As the successful application of numerical models depends on their suitability to represent the behavior related to the intended use, they should be validated by experimentally obtained results. If the discrepancy between numerically derived and experimentally obtained results is not acceptable, a model revision or a revision of the experiment need to be considered. Model revision is divided into two classes, the model updating and the basic revision of the numerical model. The presented thesis is related to a special branch of model updating, the vibration-based model updating. Vibration-based model updating is a tool to improve the correlation of the numerical model by adjusting uncertain model input parameters by means of results extracted from vibration tests. Evidently, uncertainties related to the experiment, the numerical model, or the applied numerical solving strategies can influence the correctness of the identified model input parameters. The reduction of uncertainties for two critical problems and the quantification of uncertainties related to the investigation of several nominally identical structures are the main emphases of this thesis. First, the reduction of uncertainties by optimizing reference sensor positions is considered. The presented approach relies on predicted power spectral amplitudes and an initial finite element model as a basis to define the assessment criterion for predefined sensor positions. In combination with geometry-based design variables, which represent the sensor positions, genetic and particle swarm optimization algorithms are applied. The applicability of the proposed approach is demonstrated on a numerical benchmark study of a simply supported beam and a case study of a real test specimen. Furthermore, the theory of determining the predicted power spectral amplitudes is validated with results from vibration tests. Second, the possibility to reduce uncertainties related to an inappropriate assignment for numerically derived and experimentally obtained modes is investigated. In the context of vibration-based model updating, the correct pairing is essential. The most common criterion for indicating corresponding mode shapes is the modal assurance criterion. Unfortunately, this criterion fails in certain cases and is not reliable for automatic approaches. Hence, an alternative criterion, the energy-based modal assurance criterion, is proposed. This criterion combines the mathematical characteristic of orthogonality with the physical properties of the structure by modal strain energies. A numerical example and a case study with experimental data are presented to show the advantages of the proposed energy-based modal assurance criterion in comparison to the traditional modal assurance criterion. Third, the application of optimization strategies combined with information theory based objective functions is analyzed for the purpose of stochastic model updating. This approach serves as an alternative to the common sensitivity-based stochastic model updating strategies. Their success depends strongly on the defined initial model input parameters. In contrast, approaches based on optimization strategies can be more flexible. It can be demonstrated, that the investigated nature inspired optimization strategies in combination with Bhattacharyya distance and Kullback-Leibler divergence are appropriate. The obtained accuracies and the respective computational effort are comparable with sensitivity-based stochastic model updating strategies. The application of model updating procedures to improve the quality and suitability of a numerical model is always related to additional costs. The presented innovative approaches will contribute to reduce and quantify uncertainties within a vibration-based model updating process. Therefore, the increased benefit can compensate the additional effort, which is necessary to apply model updating procedures.},
  subject      = {Dynamik},
  language  = {en}
}
@article{BrehmZabelBucher,
  author    = {Brehm, Maik and Zabel, Volkmar and Bucher, Christian},
  title     = {An automatic mode pairing strategy using an enhanced modal assurance citerion based on modal strain energies},
  series = {Journal of Sound and Vibration},
  journal   = {Journal of Sound and Vibration},
  doi       = {10.1016/j.jsv.2010.07.006},
  pages     = {5375 -- 5392},
  abstract  = {In the context of finite element model updating using output-only vibration test data, natural frequencies and mode shapes are used as validation criteria. Consequently, the correct pairing of experimentally obtained and numerically derived natural frequencies and mode shapes is important. In many cases, only limited spatial information is available and noise is present in the measurements. Therefore, the automatic selection of the most likely numerical mode shape corresponding to a particular experimentally identified mode shape can be a difficult task. The most common criterion for indicating corresponding mode shapes is the modal assurance criterion. Unfortunately, this criterion fails in certain cases and is not reliable for automatic approaches. In this paper, the purely mathematical modal assurance criterion will be enhanced by additional physical information from the numerical model in terms of modal strain energies. A numerical example and a benchmark study with experimental data are presented to show the advantages of the proposed energy-based criterion in comparison to the traditional modal assurance criterion.},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{BrehmZabelBucher,
  author    = {Brehm, Maik and Zabel, Volkmar and Bucher, Christian},
  title     = {Optimal reference sensor positions for applications in model updating using output-only vibration test data based on random excitation: Part 2 - improved search strategy and experimental case study},
  series = {Mechanical Systems and Signal Processing},
  journal   = {Mechanical Systems and Signal Processing},
  abstract  = {Optimal reference sensor positions for applications in model updating using output-only vibration test data based on random excitation: Part 2 - improved search strategy and experimental case study},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@inproceedings{BrehmZabelBucheretal.,
  author    = {Brehm, Maik and Zabel, Volkmar and Bucher, Christian and Ribeiro, D.},
  title     = {AN AUTOMATIC MODE SELECTION STRATEGY FOR MODEL UPDATING USING THE MODAL ASSURANCE CRITERION AND MODAL STRAIN ENERGIES},
  editor    = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten},
  organization    = {Bauhaus-Universit{\"a}t Weimar},
  issn      = {1611-4086},
  doi       = {10.25643/bauhaus-universitaet.2833},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28330},
  pages     = {18},
  abstract  = {In the context of finite element model updating using vibration test data, natural frequencies and mode shapes are used as validation criteria. Consequently, the order of natural frequencies and mode shapes is important. As only limited spatial information is available and noise is present in the measurements, the automatic selection of the most likely numerical mode shape corresponding to a measured mode shape is a difficult task. The most common criterion to indicate corresponding mode shapes is the modal assurance criterion. Unfortunately, this criterion fails in certain cases. In this paper, the pure mathematical modal assurance criterion will be enhanced by additional physical information of the numerical model in terms of modal strain energies. A numerical example and a benchmark study with real measured data are presented to show the advantages of the enhanced energy based criterion in comparison to the traditional modal assurance criterion.},
  subject      = {Angewandte Informatik},
  language  = {en}
}
@article{BruhinStockDrueckeretal.,
  author    = {Bruhin, R. and Stock, U.A. and Dr{\"u}cker, J.-P. and Azhari, T. and Wippermann, J. and Albes, J.M. and Hintze, D. and Eckardt, Stefan and K{\"o}nke, Carsten and Wahlers, T.},
  title     = {Numerical simulation techniques to study the structural response of the human chest following median sternotomy},
  series = {The Annals of Thoracic Surgery},
  journal   = {The Annals of Thoracic Surgery},
  pages     = {623 -- 630},
  abstract  = {Numerical simulation techniques to study the structural response of the human chest following median sternotomy},
  subject      = {Angewandte Mathematik},
  language  = {en}
}
@article{BucherEbert,
  author    = {Bucher, Christian and Ebert, Matthias},
  title     = {Nichtlineare Berechnung von Stahlflanschverbindungen mit gemessenen Imperfektionen},
  series = {Stahlbau},
  journal   = {Stahlbau},
  pages     = {516 -- 522},
  abstract  = {Nichtlineare Berechnung von Stahlflanschverbindungen mit gemessenen Imperfektionen},
  subject      = {Angewandte Mathematik},
  language  = {de}
}
@article{BucherFrangopol,
  author    = {Bucher, Christian and Frangopol, D.M.},
  title     = {Optimization of lifetime maintenance strategies for deteriorting structures considering probabilities of violating safety, condition, and cost thresholds},
  series = {Probabilistic Engineering Mechanics},
  journal   = {Probabilistic Engineering Mechanics},
  pages     = {1 -- 8},
  abstract  = {Optimization of lifetime maintenance strategies for deteriorting structures considering probabilities of violating safety, condition, and cost thresholds},
  subject      = {Angewandte Mathematik},
  language  = {en}
}