@inproceedings{DjordjevicPetkovicZivkovic, author = {Djordjevic, Djordje and Petkovic, Dusan and Zivkovic, Darko}, title = {THE APPLICATION OF INTERVAL CALCULUS TO ESTIMATION OF PLATE DEFLECTION BY SOLVING POISSON'S PARTIAL DIFFERENTIAL EQUATION}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2839}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28397}, pages = {12}, abstract = {This paper describes the application of interval calculus to calculation of plate deflection, taking in account inevitable and acceptable tolerance of input data (input parameters). The simply supported reinforced concrete plate was taken as an example. The plate was loaded by uniformly distributed loads. Several parameters that influence the plate deflection are given as certain closed intervals. Accordingly, the results are obtained as intervals so it was possible to follow the direct influence of a change of one or more input parameters on output (in our example, deflection) values by using one model and one computing procedure. The described procedure could be applied to any FEM calculation in order to keep calculation tolerances, ISO-tolerances, and production tolerances in close limits (admissible limits). The Wolfram Mathematica has been used as tool for interval calculation.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{EblingScheuermann, author = {Ebling, Julia and Scheuermann, G.}, title = {TEMPLATE MATCHING ON VECTOR FIELDS USING CLIFFORD ALGEBRA}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2946}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29464}, pages = {25}, abstract = {Due to the amount of flow simulation and measurement data, automatic detection, classification and visualization of features is necessary for an inspection. Therefore, many automated feature detection methods have been developed in recent years. However, only one feature class is visualized afterwards in most cases, and many algorithms have problems in the presence of noise or superposition effects. In contrast, image processing and computer vision have robust methods for feature extraction and computation of derivatives of scalar fields. Furthermore, interpolation and other filter can be analyzed in detail. An application of these methods to vector fields would provide a solid theoretical basis for feature extraction. The authors suggest Clifford algebra as a mathematical framework for this task. Clifford algebra provides a unified notation for scalars and vectors as well as a multiplication of all basis elements. The Clifford product of two vectors provides the complete geometric information of the relative positions of these vectors. Integration of this product results in Clifford correlation and convolution which can be used for template matching of vector fields. For frequency analysis of vector fields and the behavior of vector-valued filters, a Clifford Fourier transform has been derived for 2D and 3D. Convolution and other theorems have been proved, and fast algorithms for the computation of the Clifford Fourier transform exist. Therefore the computation of Clifford convolution can be accelerated by computing it in Clifford Fourier domain. Clifford convolution and Fourier transform can be used for a thorough analysis and subsequent visualization of flow fields.}, subject = {Architektur }, language = {en} } @inproceedings{BultheelJansenMaesetal., author = {Bultheel, Adhemar and Jansen, M. and Maes, J. and Van Aerschot, W. and Vanraes, E.}, title = {SUBDIVIDE AND CONQUER RESOLUTION}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2909}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29091}, pages = {47}, abstract = {This contribution will be freewheeling in the domain of signal, image and surface processing and touch briefly upon some topics that have been close to the heart of people in our research group. A lot of the research of the last 20 years in this domain that has been carried out world wide is dealing with multiresolution. Multiresolution allows to represent a function (in the broadest sense) at different levels of detail. This was not only applied in signals and images but also when solving all kinds of complex numerical problems. Since wavelets came into play in the 1980's, this idea was applied and generalized by many researchers. Therefore we use this as the central idea throughout this text. Wavelets, subdivision and hierarchical bases are the appropriate tools to obtain these multiresolution effects. We shall introduce some of the concepts in a rather informal way and show that the same concepts will work in one, two and three dimensions. The applications in the three cases are however quite different, and thus one wants to achieve very different goals when dealing with signals, images or surfaces. Because completeness in our treatment is impossible, we have chosen to describe two case studies after introducing some concepts in signal processing. These case studies are still the subject of current research. The first one attempts to solve a problem in image processing: how to approximate an edge in an image efficiently by subdivision. The method is based on normal offsets. The second case is the use of Powell-Sabin splines to give a smooth multiresolution representation of a surface. In this context we also illustrate the general method of construction of a spline wavelet basis using a lifting scheme.}, subject = {Architektur }, language = {en} } @inproceedings{Szolomicki, author = {Szolomicki, Jerzy Pawel}, title = {STRUCTURAL BEHAVIOUR OF MASONRY VAULTS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2896}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28966}, pages = {11}, abstract = {This paper deals with the modelling and the analysis of masonry vaults. Numerical FEM analyses are performed using LUSAS code. Two vault typologies are analysed (barrel and cross-ribbed vaults) parametrically varying geometrical proportions and constraints. The proposed model and the developed numerical procedure are implemented in a computer analysis. Numerical applications are developed to assess the model effectiveness and the efficiency of the numerical procedure. The main object of the present paper is the development of a computational procedure which allows to define 3D structural behaviour of masonry vaults. For each investigated example, the homogenized limit analysis approach has been employed to predict ultimate load and failure mechanisms. Finally, both a mesh dependence study and a sensitivity analysis are reported. Sensitivity analysis is conducted varying in a wide range mortar tensile strength and mortar friction angle with the aim of investigating the influence of the mechanical properties of joints on collapse load and failure mechanisms. The proposed computer model is validated by a comparison with experimental results available in the literature.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{BauerRichter, author = {Bauer, Marek and Richter, Matthias}, title = {STATISTICAL ANALYSIS OF TIME LOST BY TRAMS BEFORE DEPARTURE FROM STOPS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2922}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29226}, pages = {18}, abstract = {The ride of the tram along the line, defined by a time-table, consists of the travel time between the subsequent sections and the time spent by tram on the stops. In the paper, statistical data collected in the city of Krakow is presented and evaluated. In polish conditions, for trams the time spent on stops makes up the remarkable amount of 30 \% of the total time of tram line operation. Moreover, this time is characterized by large variability. The time spent by tram on a stop consists of alighting and boarding time and time lost by tram on stop after alighting and boarding time ending, but before departure. Alighting and boarding time itself usually depends on the random number of alighting and boarding passengers and also on the number of passengers which are inside the vehicle. However, the time spent by tram on stop after alighting and boarding time ending is an effect of certain random events, mainly because of impossibility of departure from stop, caused by lack of priorities for public transport vehicles. The main focus of the talk lies on the description and the modelling of these effects. This paper is involved with CIVITAS-CARAVEL project: "Clean and better transport in cites". The project has received research funding from the Community's Sixth Framework Programme. The paper reflects only the author's views and the Community is not liable for any use that may be made of the information contained therein.}, subject = {Architektur }, language = {en} } @inproceedings{Petrova, author = {Petrova, Lyllia B.}, title = {STATIC ANALYSIS ON MODELS OF CONTINUOUS ORTHOTROPIC THIN-WALLED PRISMATIC SHELL STRUCTURES}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.3000}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-30007}, pages = {8}, abstract = {The paper presents a linear static analysis on continuous orthotropic thin-walled shell structures simply supported at the transverse ends with a random deformable contour of the cross section. The external loads can be random as well. The class of this structures involves most of the bridges, scaffold bridges, some roof structures etc. A numerical example of steel continuous structures on five spans with an open contour of the cross-section has been solved. The examination of the structure has used the following two computation models: a prismatic structure consisting of isotropic strips, a plates and ribs, with considering their real interaction, and a smooth orthotropic plate equivalent to the structure in the first model. The displacements and forces of the structure characterizing its stressed and deformed condition have been determined. The results obtained from the two solutions have been analyzed. The study on the structure is made with the force method in combination with the analytical finite strip method (AFSM) in displacements. The basic system is obtained by separating the superstructure from the understructure at the places of intermediate supports and consists of two parts. The first part is a single span thin-walled prismatic shell structure; the second part presents supports (columns, space frames etc.). The connection between the superstructure and intermediate supports is made under random supporting conditions. The forces at the supporting points in the direction of the connections removed are assumed to be the basic unknowns of the force method. The solution of the superstructure has been accomplished by the AFSM in displacements. The structure is divided in only one (transverse) direction into a finite number of plain strips connected to each other in longitudinal linear nodes. The three displacements of the points on the node lines and the rotation around those lines have been assumed to be the basic unknown in each node. The boundary conditions of each strip of the basic system correspond to the simply support along the transverse ends and the restraint along the longitudinal ones. The particular strip of the basic system has been solved by the method of the single trigonometric series. The method is reduced to solving a discrete structure in displacements and restoring its continuity at the places of the sections made in respect to both the displacements and forces. The two parts of the basic system have been solved in sequence under the action of single values of each of the basic unknowns and with the external load. The solution of the support part is accomplished using software for analyzing structures by the FEM. The basic unknown forces have been determined from system of canonic equations, the conditions of the deformations continuity on the places of the removed connections under superstructure and intermediate supports. The final displacements and forces at a random point of a continuous superstructure have been determined using the principle of superposition. The computations have been carried by software developed with Visual Fortran version 5.0 for PC.}, subject = {Architektur }, language = {en} } @inproceedings{Malonek, author = {Malonek, Helmuth Robert}, title = {SPECIAL FUNCTIONS VERSUS ELEMENTARY FUNCTIONS IN HYPERCOMPLEX FUNCTION THEORY}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2870}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28702}, pages = {3}, abstract = {In recent years special hypercomplex Appell polynomials have been introduced by several authors and their main properties have been studied by different methods and with different objectives. Like in the classical theory of Appell polynomials, their generating function is a hypercomplex exponential function. The observation that this generalized exponential function has, for example, a close relationship with Bessel functions confirmed the practical significance of such an approach to special classes of hypercomplex differentiable functions. Its usefulness for combinatorial studies has also been investigated. Moreover, an extension of those ideas led to the construction of complete sets of hypercomplex Appell polynomial sequences. Here we show how this opens the way for a more systematic study of the relation between some classes of Special Functions and Elementary Functions in Hypercomplex Function Theory.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{Loemker, author = {L{\"o}mker, Thorsten Michael}, title = {SOLVING REVITALIZATION-PROBLEMS BY THE USE OF A CONSTRAINT PROGRAMING LANGUAGE}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2987}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29874}, pages = {13}, abstract = {This research focuses on an approach to describe principles in architectural layout planning within the domain of revitalization. With the aid of mathematical rules, which are executed by a computer, solutions to design problems are generated. Provided that "design" is in principle a combinatorial problem, i.e. a constraint-based search for an overall optimal solution of a problem, an exemplary method will be described to solve such problems in architectural layout planning. To avoid conflicts relating to theoretical subtleness, a customary approach adopted from Operations Research has been chosen in this work. In this approach, design is a synonym for planning, which could be described as a systematic and methodical course of action for the analysis and solution of current or future problems. The planning task is defined as an analysis of a problem with the aim to prepare optimal decisions by the use of mathematical methods. The decision problem of a planning task is represented by an optimization model and the application of an efficient algorithm in order to aid finding one or more solutions to the problem. The basic principle underlying the approach presented herein is the understanding of design in terms of searching for solutions that fulfill specific criteria. This search is executed by the use of a constraint programming language.}, subject = {Architektur }, language = {en} } @inproceedings{PerepelitsaTebuevaShenkao, author = {Perepelitsa, V. A. and Tebueva, F.B. and Shenkao, Timour}, title = {SOLVABILITY EXPLORATION OF SEGMENTATION PROBLEM WITH LINEAR CONVOLUTION ALGORITHMS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2999}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29999}, pages = {13}, abstract = {The paper is dedicated to decidability exploration of market segmentation problem with the help of linear convolution algorithms. Mathematical formulation of this problem represents interval task of bipartite graph cover by stars. Vertices of the first partition correspond to types of commodities, vertices of the second - to customers groups. Appropriate method is offered for interval problem reduction to two-criterion task that has one implemented linear convolution algorithm. Unsolvability with the help of linear convolution algorithm of multicriterion, and consequently interval, market segmentation problem is proved.}, subject = {Architektur }, language = {en} } @inproceedings{EiermannErnstUllmann, author = {Eiermann, Michael and Ernst, O. and Ullmann, Elisabeth}, title = {SOLUTION STRATEGIES FOR STOCHASTIC FINITE ELEMENT DISCRETIZATIONS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2949}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29493}, pages = {11}, abstract = {We consider efficient numerical methods for the solution of partial differential equations with stochastic coefficients or right hand side. The discretization is performed by the stochastic finite element method (SFEM). Separation of spatial and stochastic variables in the random input data is achieved via a Karhunen-Lo{\`e}ve expansion or Wiener's polynomial chaos expansion. We discuss solution strategies for the Galerkin system that take advantage of the special structure of the system matrix. For stochastic coefficients linear in a set of independent random variables we employ Krylov subspace recycling techniques after having decoupled the large SFEM stiffness matrix.}, subject = {Architektur }, language = {en} }