@inproceedings{OPUS4-2374, title = {Urban Design for Mussolini, Stalin, Salazar, Hitler and Franco During the Interwar Period}, editor = {Bauhaus-Institut f{\"u}r Geschichte und Theorie der Architektur und Planung,}, doi = {10.25643/bauhaus-universitaet.2374}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150323-23746}, abstract = {Urban design played a central role for the European dictatorships during the 20th century, it served to legitimate the regime, to produce agreement, to demonstrate power, efficiency and speed, it communicated the social, as well as design projects, of the dictatorial regimes domestically and internationally, it tied old experts, as well as new, to the regime. Dictatorial urban design also played an important role after the fall of the dictatorships: It became the object of structural and verbal handling strategies: of demolition, of transformation, of reconstruction, of forgetting, of suppressing, of re-interpretation and of glorification. The topic area is, therefore, both historical and relevant to the present day. The discussion of the topic area is, like it or not, always embedded in the present state of societal engagement with dictatorships. In order to even be able to discuss all of these aspects, different conceptual decisions are necessary. In retrospect, these may seem to many as self-evident, although they are anything but. Our thesis is that there are three methodological imperatives, especially, which allow an expanded approach to the topic area "urban design and dictatorship". First and above all, the tunnel view, focused on individual dictatorships and neglecting the international dimension, must be overcome. Second, the differences in urban design over the course of a dictatorship, through an appropriate periodisation, should be emphasised. Third, we must strive for an open, flexible, but complex concept of urban design. The main focus lies on the urban design of the most influential dictatorships of the first half of the 20th century: Soviet Union, Fascist Italy and Nazi Germany, including the urban design of the autarky periods in Portugal and Spain. After all, urban design is not just a product of specific historic circumstances. It is a form that continues to have long-term effects, which demonstrates its usefulness and adaptability throughout this process. The urban design products undoubtedly still recall the dictatorial rule under which they were created. However, they are more than a memory space. They are also a living space of the present. They can and should be discussed with respect to their spatial and functional utility for today and tomorrow. Such a perspective is a given for the citizens of a city, but also for city marketing, having marvellous consequences. Only when we do not exclude this dimension a priori, even in academic discussions, can we do justice to the products of dictatorships. And finally, the view of the urban design of dictatorships can and must contribute to the questioning of simplified and naive conceptions of dictatorships. With urban design in mind, we can observe how dictatorships work and how they were able to prevail. In Europe, these questions are of the highest actuality.}, subject = {Urbanit{\"a}t}, language = {en} } @inproceedings{JaouadiLahmer, author = {Jaouadi, Zouhour and Lahmer, Tom}, title = {Topology optimization of structures subjected to multiple load cases by introducing the Epsilon constraint method}, 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.2804}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28042}, pages = {7}, abstract = {A topology optimization method has been developed for structures subjected to multiple load cases (Example of a bridge pier subjected to wind loads, traffic, superstructure...). We formulate the problem as a multi-criterial optimization problem, where the compliance is computed for each load case. Then, the Epsilon constraint method (method proposed by Chankong and Haimes, 1971) is adapted. The strategy of this method is based on the concept of minimizing the maximum compliance resulting from the critical load case while the other remaining compliances are considered in the constraints. In each iteration, the compliances of all load cases are computed and only the maximum one is minimized. The topology optimization process is switching from one load to another according to the variation of the resulting compliance. In this work we will motivate and explain the proposed methodology and provide some numerical examples.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{Vasileva, author = {Vasileva, Iuliia}, title = {THE PROBLEM OF PARTIAL REINFORCING AN INTERFACE CRACK EDGE BY A RIGID PATCH PLATE UNDER IN-PLANE AND ANTIPLANE LOADS}, 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.2824}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28242}, pages = {5}, abstract = {The stress state of a piecewise-homogeneous elastic body, which has a semi-infinite crack along the interface, under in-plane and antiplane loads is considered. One of the crack edges is reinforced by a rigid patch plate on a finite interval adjacent to the crack tip. The crack edges are loaded with specified stresses. The body is stretched at infinity by specified stresses. External forces with a given principal vector and moment act on the patch plate. The problem reduces to a Riemann-Hilbert boundary-value matrix problem with a piecewise-constant coefficient for two complex potentials in the plane case and for one in the antiplane case. The complex potentials are found explicitly using a Gaussian hypergeometric function. The stress state of the body close to the ends of the patch plate, one of which is also simultaneously the crack tip, is investigated. Stress intensity factors near the singular points are determined.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{VolkovKirschkeChelyshkovetal., author = {Volkov, Andrey and Kirschke, Heiko and Chelyshkov, Pavel and Sedov, Artem and Lysenko, Denis}, title = {THE CRITERIA'S SET WITH INVARIANT DESIGN BUILDING ELEMENTS ON THE BASE OF THREE IMPUTATIONS: "CONVENIENCE", "SAFETY" AND "ENERGY-EFFICIENCY"}, 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.2795}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27956}, pages = {6}, abstract = {The paper deals with the formalization of the criteria for constructing building management systems. We consider three criteria - "convenience", "safety" and "energyefficiency". For each objective proposed method of calculation.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{GoebelOsburgLahmer, author = {G{\"o}bel, Luise and Osburg, Andrea and Lahmer, Tom}, title = {STUDY OF ANALYTICAL MODELS OF THE MECHANICAL BEHAVIOR OF POLYMER-MODIFIED CONCRETE}, 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.2797}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27973}, pages = {9}, abstract = {Polymer modification of mortar and concrete is a widely used technique in order to improve their durability properties. Hitherto, the main application fields of such materials are repair and restoration of buildings. However, due to the constant increment of service life requirements and the cost efficiency, polymer modified concrete (PCC) is also used for construction purposes. Therefore, there is a demand for studying the mechanical properties of PCC and entitative differences compared to conventional concrete (CC). It is significant to investigate whether all the assumed hypotheses and existing analytical formulations about CC are also valid for PCC. In the present study, analytical models available in the literature are evaluated. These models are used for estimating mechanical properties of concrete. The investigated property in this study is the modulus of elasticity, which is estimated with respect to the value of compressive strength. One existing database was extended and adapted for polymer-modified concrete mixtures along with their experimentally measured mechanical properties. Based on the indexed data a comparison between model predictions and experiments was conducted by calculation of forecast errors.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{KavrakovTimmlerMorgenthal, author = {Kavrakov, Igor and Timmler, Hans-Georg and Morgenthal, Guido}, title = {STRUCTURAL OPTIMIZATION USING THE ENERGY METHOD WITH INTEGRAL MATERIAL BEHAVIOUR}, 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.2806}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28065}, pages = {6}, abstract = {With the advances of the computer technology, structural optimization has become a prominent field in structural engineering. In this study an unconventional approach of structural optimization is presented which utilize the Energy method with Integral Material behaviour (EIM), based on the Lagrange's principle of minimum potential energy. The equilibrium condition with the EIM, as an alternative method for nonlinear analysis, is secured through minimization of the potential energy as an optimization problem. Imposing this problem as an additional constraint on a higher cost function of a structural property, a bilevel programming problem is formulated. The nested strategy of solution of the bilevel problem is used, treating the energy and the upper objective function as separate optimization problems. Utilizing the convexity of the potential energy, gradient based algorithms are employed for its minimization and the upper cost function is minimized using the gradient free algorithms, due to its unknown properties. Two practical examples are considered in order to prove the efficiency of the method. The first one presents a sizing problem of I steel section within encased composite cross section, utilizing the material nonlinearity. The second one is a discrete shape optimization of a steel truss bridge, which is compared to a previous study based on the Finite Element Method.}, subject = {Angewandte Informatik}, 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} } @inproceedings{Vieira, author = {Vieira, Nelson}, title = {SOME RESULTS IN FRACTIONAL CLIFFORD ANALYSIS}, 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.2825}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28256}, pages = {6}, abstract = {What is nowadays called (classic) Clifford analysis consists in the establishment of a function theory for functions belonging to the kernel of the Dirac operator. While such functions can very well describe problems of a particle with internal SU(2)-symmetries, higher order symmetries are beyond this theory. Although many modifications (such as Yang-Mills theory) were suggested over the years they could not address the principal problem, the need of a n-fold factorization of the d'Alembert operator. In this paper we present the basic tools of a fractional function theory in higher dimensions, for the transport operator (alpha = 1/2 ), by means of a fractional correspondence to the Weyl relations via fractional Riemann-Liouville derivatives. A Fischer decomposition, fractional Euler and Gamma operators, monogenic projection, and basic fractional homogeneous powers are constructed.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{Karaki, author = {Karaki, Ghada}, title = {SELECTION AND SCALING OF GROUND MOTION RECORDS FOR SEISMIC ANALYSIS USING AN OPTIMIZATION ALGORITHM}, 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.2805}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28058}, pages = {7}, abstract = {The nonlinear time history analysis and seismic performance based methods require a set of scaled ground motions. The conventional procedure of ground motion selection is based on matching the motion properties, e.g. magnitude, amplitude, fault distance, and fault mechanism. The seismic target spectrum is only used in the scaling process following the random selection process. Therefore, the aim of the paper is to present a procedure to select a sets of ground motions from a built database of ground motions. The selection procedure is based on running an optimization problem using Dijkstra's algorithm to match the selected set of ground motions to a target response spectrum. The selection and scaling procedure of optimized sets of ground motions is presented by examining the analyses of nonlinear single degree of freedom systems.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{TanLahmerSiddappa, author = {Tan, Fengjie and Lahmer, Tom and Siddappa, Manju Gyaraganahalll}, title = {SECTION OPTIMIZATION AND RELIABILITY ANALYSIS OF ARCH-TYPE DAMS INCLUDING COUPLED MECHANICAL-THERMAL AND HYDRAULIC FIELDS}, 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.2821}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28212}, pages = {8}, abstract = {From the design experiences of arch dams in the past, it has significant practical value to carry out the shape optimization of arch dams, which can fully make use of material characteristics and reduce the cost of constructions. Suitable variables need to be chosen to formulate the objective function, e.g. to minimize the total volume of the arch dam. Additionally a series of constraints are derived and a reasonable and convenient penalty function has been formed, which can easily enforce the characteristics of constraints and optimal design. For the optimization method, a Genetic Algorithm is adopted to perform a global search. Simultaneously, ANSYS is used to do the mechanical analysis under the coupling of thermal and hydraulic loads. One of the constraints of the newly designed dam is to fulfill requirements on the structural safety. Therefore, a reliability analysis is applied to offer a good decision supporting for matters concerning predictions of both safety and service life of the arch dam. By this, the key factors which would influence the stability and safety of arch dam significantly can be acquired, and supply a good way to take preventive measures to prolong ate the service life of an arch dam and enhances the safety of structure.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{HartmannSmarslyLahmer, author = {Hartmann, Veronika and Smarsly, Kay and Lahmer, Tom}, title = {ROBUST SCHEDULING IN CONSTRUCTION ENGINEERING}, 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.2799}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27994}, pages = {5}, abstract = {In construction engineering, a schedule's input data, which is usually not exactly known in the planning phase, is considered deterministic when generating the schedule. As a result, construction schedules become unreliable and deadlines are often not met. While the optimization of construction schedules with respect to costs and makespan has been a matter of research in the past decades, the optimization of the robustness of construction schedules has received little attention. In this paper, the effects of uncertainties inherent to the input data of construction schedules are discussed. Possibilities are investigated to improve the reliability of construction schedules by considering alternative processes for certain tasks and by identifying the combination of processes generating the most robust schedule with respect to the makespan of a construction project.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{Cravo, author = {Cravo, Salete A. F.}, title = {Restelo in Lisbon - The Non-implementation of the Original Urban Design by Faria da Costa during the Dictatorship of Ant{\´o}nio de Oliveira Salazar}, series = {Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography}, booktitle = {Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography}, doi = {10.25643/bauhaus-universitaet.2411}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150619-24111}, pages = {1 -- 17}, abstract = {Beitr{\"a}ge zum Symposium „Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography". Weimar, 21.-22. November 2013}, subject = {St{\"a}dtebau}, language = {en} } @article{KonichNikitinKlimenkoetal., author = {Konich, Kira and Nikitin, Igor and Klimenko, Stanislav and Malofeev, Valery and Tyul'bashev, Sergey}, title = {Radio Astronomical Monitoring in Virtual Environment}, series = {Procedia Computer Science}, journal = {Procedia Computer Science}, doi = {10.1016/j.procs.2015.11.067}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170425-31431}, pages = {592 -- 601}, abstract = {We present StarWatch, our application for real-time analysis of radio astronomical data in Virtual Environment. Serving as an interface to radio astronomical databases or being applied to live data from the radio telescopes, the application supports various data filters measuring signal-to-noise ratio (SNR), Doppler's drift, degree of signal localization on celestial sphere and other useful tools for signal extraction and classification. Originally designed for the database of narrow band signals from SETI Institute (setilive.org), the application has been recently extended for the detection of wide band periodic signals, necessary for the search of pulsars. We will also address the detection of week signals possessing arbitrary waveforms and present several data filters suitable for this purpose.}, subject = {Virtuelle Realit{\"a}t}, language = {en} } @inproceedings{Dattomo, author = {Dattomo, Nicla}, title = {Planning the Industrialization. The Technical and Theoretical Toolbox for the Post-War Program for the Industrial Development Areas of Southern Italy}, series = {Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography}, booktitle = {Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography}, doi = {10.25643/bauhaus-universitaet.2439}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150731-24398}, pages = {1 -- 9}, abstract = {Beitr{\"a}ge zum Symposium „Urban design and dictatorship in the 20th century: Italy, Portugal, the Soviet Union, Spain and Germany. History and Historiography". Weimar, 21.-22. November 2013}, subject = {St{\"a}dtebau}, language = {en} } @inproceedings{IgnatovaKirschkeTauscheretal., author = {Ignatova, Elena and Kirschke, Heiko and Tauscher, Eike and Smarsly, Kay}, title = {PARAMETRIC GEOMETRIC MODELING IN CONSTRUCTION PLANNING USING INDUSTRY FOUNDATION CLASSES}, 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.2802}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28024}, pages = {8}, abstract = {One of the most promising and recent advances in computer-based planning is the transition from classical geometric modeling to building information modeling (BIM). Building information models support the representation, storage, and exchange of various information relevant to construction planning. This information can be used for describing, e.g., geometric/physical properties or costs of a building, for creating construction schedules, or for representing other characteristics of construction projects. Based on this information, plans and specifications as well as reports and presentations of a planned building can be created automatically. A fundamental principle of BIM is object parameterization, which allows specifying geometrical, numerical, algebraic and associative dependencies between objects contained in a building information model. In this paper, existing challenges of parametric modeling using the Industry Foundation Classes (IFC) as a federated model for integrated planning are shown, and open research questions are discussed.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{NguyenTuanLahmerDatchevaetal., author = {Nguyen-Tuan, Long and Lahmer, Tom and Datcheva, Maria and Stoimenova, Eugenia and Schanz, Tom}, title = {PARAMETER IDENTIFICATION APPLYING IN COMPLEX THERMO-HYDRO-MECHANICAL PROBLEMS LIKE THE DESIGN OF BUFFER ELEMENTS}, 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.2816}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28162}, pages = {6}, abstract = {This study contributes to the identification of coupled THM constitutive model parameters via back analysis against information-rich experiments. A sampling based back analysis approach is proposed comprising both the model parameter identification and the assessment of the reliability of identified model parameters. The results obtained in the context of buffer elements indicate that sensitive parameter estimates generally obey the normal distribution. According to the sensitivity of the parameters and the probability distribution of the samples we can provide confidence intervals for the estimated parameters and thus allow a qualitative estimation on the identified parameters which are in future work used as inputs for prognosis computations of buffer elements. These elements play e.g. an important role in the design of nuclear waste repositories.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{StokmaierClassSchulenbergetal., author = {Stokmaier, Markus and Class, A.G. and Schulenberg, T. and Lahey Jr., R.T}, title = {OPTIMISING ACOUSTIC RESONATORS FOR SONOFUSION EXPERIMENTS WITH EVOLUTIONARY ALGORITHMS}, 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.2820}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28202}, pages = {8}, abstract = {The sizing of simple resonators like guitar strings or laser mirrors is directly connected to the wavelength and represents no complex optimisation problem. This is not the case with liquid-filled acoustic resonators of non-trivial geometries, where several masses and stiffnesses of the structure and the fluid have to fit together. This creates a scenario of many competing and interacting resonances varying in relative strength and frequency when design parameters change. Hence, the resonator design involves a parameter-tuning problem with many local optima. As its solution evolutionary algorithms (EA) coupled to a forced-harmonic FE simulation are presented. A new hybrid EA is proposed and compared to two state-of-theart EAs based on selected test problems. The motivating background is the search for better resonators suitable for sonofusion experiments where extreme states of matter are sought in collapsing cavitation bubbles.}, subject = {Angewandte Informatik}, language = {en} } @article{IlyaniAkmarKramerRabczuk, author = {Ilyani Akmar, A.B. and Kramer, O. and Rabczuk, Timon}, title = {Multi-objective evolutionary optimization of sandwich structures: An evaluation by elitist non-dominated sorting evolution strategy}, series = {American Journal of Engineering and Applied Sciences}, journal = {American Journal of Engineering and Applied Sciences}, doi = {10.3844/ajeassp.2015.185.201}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170418-31402}, pages = {185 -- 201}, abstract = {In this study, an application of evolutionary multi-objective optimization algorithms on the optimization of sandwich structures is presented. The solution strategy is known as Elitist Non-Dominated Sorting Evolution Strategy (ENSES) wherein Evolution Strategies (ES) as Evolutionary Algorithm (EA) in the elitist Non-dominated Sorting Genetic algorithm (NSGA-II) procedure. Evolutionary algorithm seems a compatible approach to resolve multi-objective optimization problems because it is inspired by natural evolution, which closely linked to Artificial Intelligence (AI) techniques and elitism has shown an important factor for improving evolutionary multi-objective search. In order to evaluate the notion of performance by ENSES, the well-known study case of sandwich structures are reconsidered. For Case 1, the goals of the multi-objective optimization are minimization of the deflection and the weight of the sandwich structures. The length, the core and skin thicknesses are the design variables of Case 1. For Case 2, the objective functions are the fabrication cost, the beam weight and the end deflection of the sandwich structures. There are four design variables i.e., the weld height, the weld length, the beam depth and the beam width in Case 2. Numerical results are presented in terms of Paretooptimal solutions for both evaluated cases.}, subject = {Optimierung}, language = {en} } @phdthesis{RodriguezSchaeffer, author = {Rodr{\´i}guez Schaeffer, Alan Paul}, title = {Lighting in urban heritage: case study of Chiapa de Corzo, Chiapas, Mexico}, doi = {10.25643/bauhaus-universitaet.2421}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150630-24217}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {327}, abstract = {As human thought was developing, likewise, the technology used for illumination was growing. But a haul through history, reviewing its pages and analyzing it, inherently brings up old and new question, like: Is it possible to alter negatively the image of historic buildings and monuments through inadequate lighting to the degree of distorting the perception that people have of the work? and if so, what are the causes that generate it? Do the light designers take into consideration criteria to protect not only historic buildings and monuments, but also the environment? What are the consequences that may generate the inadequate lighting of urban heritage to the environment? What are the factors to consider for a proper illumination of urban heritage? The answers to these questions will help lay the foundation for proper illumination of the urban heritage, avoiding at the maximum the light pollution and the effects that it generates, seeking a balance and harmonious reconciliation between the technology, urban heritage and environment, taking as a framework and the case study the urban heritage of a city from the colonial era in southern Mexico, with pre-Hispanic roots and where today you can still see through its streets and buildings an atmosphere of mysticism reflection of their folklore and traditions, this city is known as Chiapa de Corzo, Chiapas.}, subject = {Konservierung}, language = {en} } @inproceedings{SmarslyTauscher, author = {Smarsly, Kay and Tauscher, Eike}, title = {IFC-BASED MONITORING INFORMATION MODELING FOR DATA MANAGEMENT IN STRUCTURAL HEALTH MONITORING}, 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.2823}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28237}, pages = {7}, abstract = {This conceptual paper discusses opportunities and challenges towards the digital representation of structural health monitoring systems using the Industry Foundation Classes (IFC) standard. State-of-the-art sensor nodes, collecting structural and environmental data from civil infrastructure systems, are capable of processing and analyzing the data sets directly on-board the nodes. Structural health monitoring (SHM) based on sensor nodes that possess so called "on-chip intelligence" is, in this study, referred to as "intelligent SHM", and the infrastructure system being equipped with an intelligent SHM system is referred to as "intelligent infrastructure". Although intelligent SHM will continue to grow, it is not possible, on a well-defined formalism, to digitally represent information about sensors, about the overall SHM system, and about the monitoring strategies being implemented ("monitoring-related information"). Based on a review of available SHM regulations and guidelines as well as existing sensor models and sensor modeling languages, this conceptual paper investigates how to digitally represent monitoring-related information in a semantic model. With the Industry Foundation Classes, there exists an open standard for the digital representation of building information; however, it is not possible to represent monitoring-related information using the IFC object model. This paper proposes a conceptual approach for extending the current IFC object model in order to include monitoring-related information. Taking civil infrastructure systems as an illustrative example, it becomes possible to adequately represent, process, and exchange monitoring-related information throughout the whole life cycle of civil infrastructure systems, which is referred to as monitoring information modeling (MIM). However, since this paper is conceptual, additional research efforts are required to further investigate, implement, and validate the proposed concepts and methods.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{KrausshardeAlmeida, author = {Kraußhar, Rolf S{\"o}ren and de Almeida, Regina}, title = {FUNDAMENTALS OF A WIMAN VALIRON THEORY FOR POLYMONOGENIC FUNCTIONS}, 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.2810}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28100}, pages = {6}, abstract = {In this paper we present some rudiments of a generalized Wiman-Valiron theory in the context of polymonogenic functions. In particular, we analyze the relations between different notions of growth orders and the Taylor coefficients. Our main intention is to look for generalizations of the Lindel¨of-Pringsheim theorem. In contrast to the classical holomorphic and the monogenic setting we only obtain inequality relations in the polymonogenic setting. This is due to the fact that the Almansi-Fischer decomposition of a polymonogenic function consists of different monogenic component functions where each of them can have a totally different kind of asymptotic growth behavior.}, subject = {Angewandte Informatik}, language = {en} } @article{OtholdVoss, author = {Othold, Tim and Voss, Christiane}, title = {From media anthropology to anthropomediality}, series = {Anthropological Notebooks}, journal = {Anthropological Notebooks}, doi = {10.25643/bauhaus-universitaet.3157}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170425-31573}, pages = {75 -- 82}, abstract = {Media anthropology is a new and interdisciplinary field of research with very different subjects and methods that seems to be already heavily informed by a comparatively narrow understanding of media as mass media (e.g. TV, Internet, social web, etc.). Therefore, most theories in this field, at least implicitly, employ a hierarchical and often dichotomic preconception of the two poles of media-human relations, by analysing the operationalities and ontologies of the human and the media independently from one another. This article deviates from this line of thought by advocating an expanded, symmetrical and relational understanding of the terms media and human, taking them as always already intermingled facets of a broader dynamic configuration. Starting from a consideration of the historically powerful, yet overlooked media of the so-called habitat diorama, the heuristic concept of "anthropomediality" is to be developed. Eventually, this relational approach may open up a new, interesting field for interrogation of (media-)anthropological analysis in general.}, subject = {Medien}, language = {en} } @inproceedings{Rodehorst, author = {Rodehorst, Volker}, title = {EVALUATION OF THE METRIC TRIFOCAL TENSOR FOR RELATIVE THREE-VIEW ORIENTATION}, 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.2817}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28178}, pages = {7}, abstract = {In photogrammetry and computer vision the trifocal tensor is used to describe the geometric relation between projections of points in three views. In this paper we analyze the stability and accuracy of the metric trifocal tensor for calibrated cameras. Since a minimal parameterization of the metric trifocal tensor is challenging, the additional constraints of the interior orientation are applied to the well-known projective 6-point and 7-point algorithms for three images. The experimental results show that the linear 7-point algorithm fails for some noise-free degenerated cases, whereas the minimal 6-point algorithm seems to be competitive even with realistic noise.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{JahrSchlichDragosetal., author = {Jahr, Katrin and Schlich, Robert and Dragos, Kosmas and Smarsly, Kay}, title = {DECENTRALIZED AUTONOMOUS FAULT DETECTION IN WIRELESS STRUCTURAL HEALTH MONITORING SYSTEMS USING STRUCTURAL RESPONSE DATA}, 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.2803}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28031}, pages = {8}, abstract = {Sensor faults can affect the dependability and the accuracy of structural health monitoring (SHM) systems. Recent studies demonstrate that artificial neural networks can be used to detect sensor faults. In this paper, decentralized artificial neural networks (ANNs) are applied for autonomous sensor fault detection. On each sensor node of a wireless SHM system, an ANN is implemented to measure and to process structural response data. Structural response data is predicted by each sensor node based on correlations between adjacent sensor nodes and on redundancies inherent in the SHM system. Evaluating the deviations (or residuals) between measured and predicted data, sensor faults are autonomously detected by the wireless sensor nodes in a fully decentralized manner. A prototype SHM system implemented in this study, which is capable of decentralized autonomous sensor fault detection, is validated in laboratory experiments through simulated sensor faults. Several topologies and modes of operation of the embedded ANNs are investigated with respect to the dependability and the accuracy of the fault detection approach. In conclusion, the prototype SHM system is able to accurately detect sensor faults, demonstrating that neural networks, processing decentralized structural response data, facilitate autonomous fault detection, thus increasing the dependability and the accuracy of structural health monitoring systems.}, subject = {Angewandte Informatik}, language = {en} } @article{Bargstaedt, author = {Bargst{\"a}dt, Hans-Joachim}, title = {Challenges of BIM for Construction Site Operations}, series = {Procedia Engineering}, journal = {Procedia Engineering}, doi = {10.1016/j.proeng.2015.08.123}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170413-31218}, pages = {52 -- 59}, abstract = {Building Information Modeling is a powerful tool for the design and for a consistent set of data in a virtual storage. For the application in the phases of realization and on site it needs further development. The paper describes main challenges and main features, which will help the development of software to better service the needs of construction site managers}, subject = {Building Information Modeling}, language = {en} } @inproceedings{AlaladeKafleWuttkeetal., author = {Alalade, Muyiwa and Kafle, Binod and Wuttke, Frank and Lahmer, Tom}, title = {CALIBRATION OF CYCLIC CONSTITUTIVE MODELS FOR SOILS BY OSCILLATING FUNCTIONS}, 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.2793}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27932}, pages = {6}, abstract = {In order to minimize the probability of foundation failure resulting from cyclic action on structures, researchers have developed various constitutive models to simulate the foundation response and soil interaction as a result of these complex cyclic loads. The efficiency and effectiveness of these model is majorly influenced by the cyclic constitutive parameters. Although a lot of research is being carried out on these relatively new models, little or no details exist in literature about the model based identification of the cyclic constitutive parameters. This could be attributed to the difficulties and complexities of the inverse modeling of such complex phenomena. A variety of optimization strategies are available for the solution of the sum of least-squares problems as usually done in the field of model calibration. However for the back analysis (calibration) of the soil response to oscillatory load functions, this paper gives insight into the model calibration challenges and also puts forward a method for the inverse modeling of cyclic loaded foundation response such that high quality solutions are obtained with minimum computational effort. Therefore model responses are produced which adequately describes what would otherwise be experienced in the laboratory or field.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{MeierSchanz, author = {Meier, J{\"o}rg and Schanz, Tom}, title = {Benchmarking of Optimization Algorithms}, 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.2813}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28134}, pages = {6}, abstract = {In this paper, we present an empirical approach for objective and quantitative benchmarking of optimization algorithms with respect to characteristics induced by the forward calculation. Due to the professional background of the authors, this benchmarking strategy is illustrated on a selection of search methods in regard to expected characteristics of geotechnical parameter back calculation problems. Starting from brief introduction into the approach employed, a strategy for optimization algorithm benchmarking is introduced. The benchmarking utilizes statistical tests carried out on well-known test functions superposed with perturbations, both chosen to mimic objective function topologies found for geotechnical objective function topologies. Here, the moved axis parallel hyper-ellipsoid test function and the generalized Ackley test function in conjunction with an adjustable quantity of objective function topology roughness and fraction of failing forward calculations is analyzed. In total, results for 5 optimization algorithms are presented, compared and discussed.}, subject = {Angewandte Informatik}, language = {en} } @article{WangArash, author = {Wang, Quan and Arash, Behrouz}, title = {Announcement of a virtual special issue on computational carbon nanoscience}, series = {Carbon}, journal = {Carbon}, doi = {10.1016/j.carbon.2015.05.082}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170428-31695}, pages = {370 -- 372}, abstract = {The Carbon journal is pleased to introduce a themed collection of recent articles in the area of computational carbon nanoscience. This virtual special issue was assembled from previously published Carbon articles by Guest Editors Quan Wang and Behrouz Arash, and can be accessed as a set in the special issue section of the journal website homepage: www.journals.elsevier.com/carbon. The article below by our guest editors serves as an introduction to this virtual special issue, and also a commentary on the growing role of computation as a tool to understand the synthesis and properties of carbon nanoforms and their behavior in composite materials.}, subject = {Kohlenstoff}, language = {en} } @inproceedings{LopesRodriguesVilaReal, author = {Lopes, Nuno and Rodrigues, Daniela and Vila Real, Paulo}, title = {ANALYSIS OF STEEL STRUCTURAL MEMBERS IN FIRE WITH SLENDER CROSS-SECTIONS THROUGH BEAM FINITE ELEMENTS APPLYING AN EFFECTIVE CONSTITUTIVE LAW}, 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.2811}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28116}, pages = {6}, abstract = {Steel profiles with slender cross-sections are characterized by their high susceptibility to instability phenomena, especially local buckling, which are intensified under fire conditions. This work presents a study on numerical modelling of the behaviour of steel structural elements in case of fire with slender cross-sections. To accurately carry out these analyses it is necessary to take into account those local instability modes, which normally is only possible with shell finite elements. However, aiming at the development of more expeditious methods, particularly important for analysing complete structures in case of fire, recent studies have proposed the use of beam finite elements considering the presence of local buckling through the implementation of a new effective steel constitutive law. The objective of this work is to develop a study to validate this methodology using the program SAFIR. Comparisons are made between the results obtained applying the referred new methodology and finite element analyses using shell elements. The studies were made to laterally restrained beams, unrestrained beams, axially compressed columns and columns subjected to bending plus compression.}, subject = {Angewandte Informatik}, language = {en} } @phdthesis{Forler, author = {Forler, Christian}, title = {Analysis Design \& Applications of Cryptographic Building Blocks}, publisher = {Shaker Verlag}, doi = {10.25643/bauhaus-universitaet.2376}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20150330-23764}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {213}, abstract = {This thesis deals with the basic design and rigorous analysis of cryptographic schemes and primitives, especially of authenticated encryption schemes, hash functions, and password-hashing schemes. In the last decade, security issues such as the PS3 jailbreak demonstrate that common security notions are rather restrictive, and it seems that they do not model the real world adequately. As a result, in the first part of this work, we introduce a less restrictive security model that is closer to reality. In this model it turned out that existing (on-line) authenticated encryption schemes cannot longer beconsidered secure, i.e. they can guarantee neither data privacy nor data integrity. Therefore, we present two novel authenticated encryption scheme, namely COFFE and McOE, which are not only secure in the standard model but also reasonably secure in our generalized security model, i.e. both preserve full data inegrity. In addition, McOE preserves a resonable level of data privacy. The second part of this thesis starts with proposing the hash function Twister-Pi, a revised version of the accepted SHA-3 candidate Twister. We not only fixed all known security issues of Twister, but also increased the overall soundness of our hash-function design. Furthermore, we present some fundamental groundwork in the area of password-hashing schemes. This research was mainly inspired by the medial omnipresence of password-leakage incidences. We show that the password-hashing scheme scrypt is vulnerable against cache-timing attacks due to the existence of a password-dependent memory-access pattern. Finally, we introduce Catena the first password-hashing scheme that is both memory-consuming and resistant against cache-timing attacks.}, subject = {Kryptologie}, language = {en} } @inproceedings{NasirBargstaedt, author = {Nasir, A.R. and Bargst{\"a}dt, Hans-Joachim}, title = {AMELIORATING EMPLOYABILITY IN CONSTRUCTION THROUGH BIM INNOVATION}, 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.2815}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28157}, pages = {6}, abstract = {Low-skilled labor makes a significant part of the construction sector, performing daily production tasks that do not require specific technical knowledge or confirmed skills. Today, construction market demands increasing skill levels. Many jobs that were once considered to be undertaken by low or un-skilled labor, now demand some kind of formal skills. The jobs that require low skilled labor are continually decreasing due to technological advancement and globalization. Jobs that previously required little or no training now require skilful people to perform the tasks appropriately. The study aims at ameliorating employability of less skilled manpower by finding ways to instruct them for performing constructions tasks. A review of exiting task instruction methodologies in construction and the underlying gaps within them warrants an appropriate way to train and instruct low skilled workers for the tasks in construction. The idea is to ensure the required quality of construction with technological and didactic aids seeming particularly purposeful to prepare potential workers for the tasks in construction without exposing them to existing communication barriers. A BIM based technology is considered promising along with the integration of visual directives/animations to elaborate the construction tasks scheduled to be carried on site.}, subject = {Angewandte Informatik}, language = {en} } @misc{Damanik, type = {Master Thesis}, author = {Damanik, Batta Septo Van Bahtiar}, title = {Aerodynamic Analysis of Slender Vertical Structure and Response Control with Tuned Mass Damper}, doi = {10.25643/bauhaus-universitaet.2471}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20151030-24714}, school = {Bauhaus-Universit{\"a}t Weimar}, abstract = {Analysis of vortex induced vibration has gained more interest in practical held of civil engineering. The phenomenon often occurs in long and slender vertical structure like high rise building, tower, chimney or bridge pylon, which resulting in unfavorable responses and might lead to the collapse of the structures. The phenomenon appears when frequency of vortex shedding produced in the wake area of body meet the natural frequency of the structure. Even though this phenomenon does not necessarily generate a divergent amplitude response, the structure still may fail due to fatigue damage. To reduce the effect of vortex induced vibration, engineers widely use passive vibration response control system. In this case, the thesis studies the effect of tuned mass damper. The objective of this thesis is to simulate the effect of tuned mass damper in reducing unfavorable responses due to vortex induced vibration and initiated by numerical model validation with respect to wind tunnel test report. The reference structure that being used inside the thesis is Stonecutter Bridge, Hongkong. A numerical solver for computational uid dynamics named VX ow which developed by Morgenthal [6] is utilized for wind and structure simulation. The comparison between numerical model and wind tunnel result shows 10\% maximum tip displacement diference in the model of full erection freestanding tower. The tuned mass damper (TMD) model itself built separately in finite element software SOFiSTiK, and the efective damping obtained from this model then applied inside input modal data of VX ow simulation. A single TMD with mass ratio of TMD 0.5\% to the mass of first bending frequency, the maximum tip displacement is measured to be average 67\% reduced. Considering construction limitation and robustness of TMD, the effects of multiple TMD inside a structure are also studied. An uncoupled procedure of applying aeroelastic loads obtained from VX ow inside finite element software SOFiSTiK is also done to observe the optimum distribution and optimum mass ratio of multiple tuned mass damper. The rest of the properties of TMD are calculated with Den Hartog's formula. The results are as follows: peak displacement in the case of multiple TMD that distributed with polynomial spacing achieve 7.8\% more reduction performance than the one that distributed with equal spacing. Optimum mass of tuned mass damper achieved with ratio 1.25\% mass of first bending frequency corresponds to across wind direction.}, subject = {Aerodynamic}, language = {en} } @phdthesis{Sowoidnich, author = {Sowoidnich, Thomas}, title = {A Study of Retarding Effects on Cement and Tricalcium Silicate Hydration induced by Superplasticizers}, isbn = {978-3-00-052204-8}, doi = {10.25643/bauhaus-universitaet.2544}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20160224-25444}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {214}, abstract = {Fließmittel werden in Betonen verwendet, um deren Fließeigenschaften w{\"a}hrend der Verarbeitung zu verbessern und Wasser einzusparen. Beide Faktoren beeinflussen nicht nur den Frischbeton, sondern auch signifikant die Festbetoneigenschaften. Nachteilig wirken sich Fließmittel auf die Festigkeitsentwicklung aus, die z.T. sehr stark verz{\"o}gert wird. Dies ist vor allem bei Bauteilen, die im Rahmen eines Vorfertigungsprozesses hergestellt werden, ein {\"o}konomischer Nachteil. Die vorliegende Arbeit widmet sich den Ursachen f{\"u}r die Verz{\"o}gerung der Portlandzementhydratation bei Verwendung von Fließmitteln. Um die komplexen Reaktionen, die w{\"a}hrend der Portlandzementhydratation auftreten, zu vereinfachen, betrachtet ein {\"u}berwiegender Teil der Arbeit die Wechselwirkung Fließmittel-Tricalciumsilikat (Abk. Ca3SiO5 oder C3S, Hauptbestandteil von Portlandzementklinker). Die Untersuchungen werden in drei Hauptteilen durchgef{\"u}hrt, wobei Methoden wie u.a. isotherme W{\"a}rmeflusskalorimetrie, Elektrische Leitf{\"a}higkeit, Elektronenmikroskopie, ICP-OES, TOC als auch Analytische Ultrazentrifugation Anwendung finden. Basierend auf der Wechselwirkung von Kationen mit anionischen Ladungstr{\"a}gern von Polymeren wird die Interaktion von Calcium mit Fließmitteln im ersten Teil der Arbeit untersucht. Dabei kommt es {\"u}berwiegend zur Komplexierung von Calciumionen durch die funktionellen Gruppen der Plymere (Carboxyl- bzw. Sulfonguppen), die in zement{\"a}ren Umgebungen sowohl gel{\"o}st in der w{\"a}ssrigen Phase als auch als Bestandteil von Partikelgrenzfl{\"a}chen vorhanden sind. Neben diesen Effekten kann auch gezeigt werden, dass Fließmittel die Bildung von nanoskaligen Partikeln hervorrufen, die infolge der sterischen Wirkung von Fließmitteln dispergiert in der w{\"a}ssrigen Phase vorliegen (Clusterbildung). Analog zu neuesten Erkenntnissen aus dem Bereich der Biomineralisation ist daher davon auszugehen, dass diese Nanopartikel durch Agglomeration das Kristallwachtsum beeinflussen. Ausgehend von der Annahme, dass die Aufl{\"o}sungs- und/ oder F{\"a}llungskinetik durch die Wirkung von Fließmitteln behindert und damit f{\"u}r den Verz{\"o}gerungseffekt der Fließmittel w{\"a}hrend der komplexen Hydratationsreaktion verantwortlich seien k{\"o}nnen, werden die zugrundeliegenden Vorg{\"a}nge im zweiten Abschnitt getrennt voneinander untersucht. Es wird anhand von L{\"o}sungsuntersuchungen an C-S-H Phasen und Portlandit herausgestellt, dass die Komplexierung von gel{\"o}sten Calciumionen durch funktionelle Gruppen der Polymere die L{\"o}slichkeit von Portlandit erh{\"o}ht. Im Gegensatz f{\"u}hrt die Komplexierung von Calciumionen in der w{\"a}ssrigen Phase zu einer Verringerung der Calciumionenkonzentration in der w{\"a}ssrigen Phase. Diese Effekte werden auf die unterschiedlich starke Adsorptionsneigung der Polymere an C-S-H-Phasen und Portlandit zur{\"u}ckgef{\"u}hrt. Es wird davon ausgegangen, dass die Adsorption aufgrund der gr{\"o}ßeren spezifischen Oberfl{\"a}che st{\"a}rker an den C-S-H-Phasen als am Portlandit auftritt. Demnach stellt sich dar, dass die Polymere erst nachdem die funktionellen Gruppen Calciumionen aus der w{\"a}ssrigen Phase komplexiert haben an den C-S-H-Phasen adsorbieren. Weiterhin kann gezeigt werden, dass die freie C3S Aufl{\"o}sungsrate in Anwesenheit von Fließmitteln keinen direkten Zusammenhang zur Verz{\"o}gerung erkennen l{\"a}sst. Teilweise kommt es zu einer in Bezug zur Kontrollprobe ohne Fließmittel erh{\"o}hten sowie auch verringerten Aufl{\"o}sungsrate. Wird das Komplexierungsvem{\"o}gen der Fließmittel ber{\"u}cksichtigt, so kann durchaus eine verlangsamte freie Aufl{\"o}sungsrate ermittelt werden. Doch auch Calcit zeigt einen verz{\"o}gernden Einfluss auf die freie C3S Aufl{\"o}sung, obwohl es den Gesamtprozess der Hydratation signifikant beschleunigt. Somit kann die behinderte Aufl{\"o}sung als m{\"o}gliche Ursache f{\"u}r die verz{\"o}gernde Wirkung w{\"a}hrend der Zementhydratation weder best{\"a}tigt noch widerlegt werden. Dieser Punkt sollte in zuk{\"u}nftigen Arbeiten weiter untersucht werden. Im letzten Schritt dieses Untersuchungsabschnitts wird die reine Kristallisation von C-S-H-Phasen und Portlandit untersucht. Es stellt sich heraus, dass Fließmittel insbesondere durch die Wirkung der Komplexierung von Ionen in der w{\"a}ssrigen Phase sowohl die Induktionszeit verl{\"a}ngern als auch die Kristallwachstumsrate ver{\"a}ndern. Dies allein kann aber nicht die komplette Verz{\"o}gerungswirkung erkl{\"a}ren. Ein wichtiger Verz{\"o}gerungsfaktor ist die Adsorption der Polymere an Kristalloberfl{\"a}chen als auch eine fließmittelbedingte Dispergierung von nanoskaligen Einzelpartikeln, die deren Agglomeration zu Kristallen behindert. Im letzten Hauptuntersuchungsabschnitt werden die gewonnenen Erkenntnisse auf die w{\"a}hrend der Zement- und Tricalciumsilikathydratation parallel ablaufenden Reaktionen analysiert. Dabei wird insbesondere die ionische Zusammensetzung der w{\"a}ssrigen Phase von C3S Pasten und Suspensionen untersucht, um Hinweise f{\"u}r eine kinetische Hemmung der Hydratationsreaktion zu identifizieren. Zusammenfassend wird festgestellt, dass die Ursachen der verz{\"o}gernden Wirkung von Fließmitteln auf die Hydratation von C3S auf die starke Verz{\"o}gerung der Kristallisation von Hydratphasen zur{\"u}ckzuf{\"u}hren ist. Dabei kommt den zwei Faktoren Komplexierung von Calciumionen an Oberfl{\"a}chen und Stabilisierung von nanoskaligen Partikeln eine zentrale Bedeutung zu. Diese Effekte k{\"o}nnen durch die Wirkung als Templat als auch durch Erh{\"o}hung der L{\"o}slichkeit infolge Komplexierung freier/gel{\"o}ster Ionen teilkompensiert werden. Dass die Aufl{\"o}sungsreaktion durch die Anwesenheit von Fließmitteln behindert wird, kann nur indirekt anhand der Entwicklung von Ionenkonzentrationen festgestellt werden. Ob dieser Vorgang die Ursache oder die Folge des L{\"o}sungs-F{\"a}llungs-Mechanismus der Hydratation ist und damit die verz{\"o}gernde Wirkung durch behinderte Aufl{\"o}sung des Edukts hervorgerufen wird, bleibt Gegenstand weiterer Untersuchungen. Im Rahmen der Arbeit kann auch gezeigt werden, dass Fließmittel chemisch als Inhibitoren wirken indem sie den Frequenzfaktor verringern. Dar{\"u}ber hinaus wird erstmalig eine Methode entwickelt, die die Bestimmung der Ionenkonzentration in Pasten in-situ erlaubt. Mit deren Hilfe wird dargestellt, dass die Entwicklung der Ionenkonzentration als auch die allgemein verwendete W{\"a}rmefreisetzungsrate (Kalorimetrie) miteinander korrespondiert. Dar{\"u}ber hinaus erlaubt die entwickelte Methode die weitere Differenzierung der Accelerationsperiode in drei Stadien. Die Kristallisation von C-S-H-Phasen und Portlandit ist f{\"u}r den Beginn der Haupthydratationsperiode entscheidend.}, subject = {Cement}, language = {en} } @inproceedings{WiggenbrockSmarsly, author = {Wiggenbrock, Jens and Smarsly, Kay}, title = {A GENERIC FRAMEWORK SUPPORTING DISTRIBUTED COMPUTING IN ENGINEERING APPLICATIONS}, 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.2826}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-28260}, pages = {9}, abstract = {Modern distributed engineering applications are based on complex systems consisting of various subsystems that are connected through the Internet. Communication and collaboration within an entire system requires reliable and efficient data exchange between the subsystems. Middleware developed within the web evolution during the past years provides reliable and efficient data exchange for web applications, which can be adopted for solving the data exchange problems in distributed engineering applications. This paper presents a generic approach for reliable and efficient data exchange between engineering devices using existing middleware known from web applications. Different existing middleware is examined with respect to the suitability in engineering applications. In this paper, a suitable middleware is shown and a prototype implementation simulating distributed wind farm control is presented and validated using several performance measurements.}, subject = {Angewandte Informatik}, language = {en} }