@inproceedings{ZimmermannBartels, author = {Zimmermann, J{\"u}rgen and Bartels, Jan-Hendrik}, title = {TREE-BASED METHODS FOR RESOURCE INVESTMENT AND RESOURCE LEVELLING PROBLEMS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.3040}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-30405}, pages = {6}, abstract = {The execution of project activities generally requires the use of (renewable) resources like machines, equipment or manpower. The resource allocation problem consists in assigning time intervals to the execution of the project activities while taking into account temporal constraints between activities emanating from technological or organizational requirements and costs incurred by the resource allocation. If the total procurement cost of the different renewable resources has to be minimized we speak of a resource investment problem. If the cost depends on the smoothness of the resource utilization over time the underlying problem is called a resource levelling problem. In this paper we consider a new tree-based enumeration method for solving resource investment and resource levelling problems exploiting some fundamental properties of spanning trees. The enumeration scheme is embedded in a branch-and-bound procedure using a workload-based lower bound and a depth first search. Preliminary computational results show that the proposed procedure is promising for instances with up to 30 activities.}, subject = {Architektur }, language = {en} } @inproceedings{Bauch2006, author = {Bauch, Ullrich}, title = {Transparenz im {\"A}nderungsmanagement - ein Vorteil f{\"u}r alle Vertragspartner?}, doi = {10.25643/bauhaus-universitaet.846}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-8460}, year = {2006}, subject = {Weimar / Bauhaus-Universit{\"a}t / Professur Baubetrieb und Bauverfahren}, language = {de} } @inproceedings{HuhntGielsdorf, author = {Huhnt, Wolfgang and Gielsdorf, F.}, title = {TOPOLOGICAL INFORMATION AS LEADING INFORMATION IN BUILDING PRODUCT MODELS}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2911}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29110}, pages = {11}, abstract = {Digital models of buildings are widely used in civil engineering. In these models, geometric information is used as leading information. Engineers are used to have geometric information, and, for instance, it is state of the art to specify a point by its three coordinates. However, the traditional approaches have disadvantages. Geometric information is over-determined. Thus, more geometric information is specified and stored than needed. In addition, engineers already deal with topological information. A denotation of objects in buildings is of topological nature. It has to be answered whether approaches where topological information becomes a leading role would be more efficient in civil engineering. This paper presents such an approach. Topological information is modelled independently of geometric information. It is used for denoting the objects of a building. Geometric information is associated to topological information so that geometric information "weights" a topology. The concept presented in this paper has already been used in surveying existing buildings. Experiences in the use of this concept showed that the number of geometric information that is required for a complete specification of a building could be reduced by a factor up to 100. Further research will show how this concept can be used in planning processes.}, subject = {Architektur }, language = {en} } @inproceedings{WolkowiczRuthStahr, author = {Wolkowicz, Christian and Ruth, J{\"u}rgen and Stahr, Alexander}, title = {TOOL TO CHECK TOPOLOGY AND GEOMETRY FOR SPATIAL STRUCTURES ON BASIS OF THE EXTENDED MAXWELL'S RULE}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.3037}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-30370}, pages = {8}, abstract = {One of the simplest principle in the design of light-weight structures is to avoid bending. This can be achieved by dissolving girders into members acting purely in axial tension or compression. The employment of cables for the tensioned members leads to even lighter structures which are called cable-strut structures. They constitute a subclass of spatial structures. To give fast information about the general feasibility of an architectural concept employing cable-strut structures is a challenging task due to their sophisticated mechanical behavior. In this regard it is essential to control if the structure is stable and if pre-stress can be applied. This paper presents a tool using the spreadsheet software Microsoft (MS) Excel which can give such information. Therefore it is not necessary to purchase special software and the according time consuming training is much lower. The tool was developed on basis of the extended Maxwell's rule, which besides topology also considers the geometry of the structure. For this the rank of the node equilibrium matrix is crucial. Significance and determination of the rank and the implementation of the corresponding algorithms in MS Excel are described in the following. The presented tool is able to support the structural designer in an early stage of the project in finding a feasible architectural concept for cable-strut structures. As examples for the application of the software tool two special cable-strut structures, so called tensegrity structures, were examined for their mechanical behavior.}, subject = {Architektur }, language = {en} } @inproceedings{ChangChang, author = {Chang, Wei-Tsang and Chang, Teng-Wen}, title = {TIME-BASED FORM TRANSFORMATION WITH FOLDING SPACE}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2937}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29371}, pages = {10}, abstract = {Design activity could be treated as state transition computationally. In stepwise processing, in-between form-states are not easily observed. However, in this research time-based concept is introduced and applied in order to bridge the gap. In architecture, folding is one method of form manipulation and architects also want to search for alternatives by this operation. Besides, folding operation has to be defined and parameterized before time factor is involved as a variable of folding. As a result, time-based transformation provides sequential form states and redirects design activity.}, subject = {Architektur }, language = {en} } @inproceedings{Heuer, author = {Heuer, Andreas}, title = {THREE-DIMENSIONAL MODELING OF CONCRETE WITH DAMAGE AND PLASTICITY}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2967}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29671}, pages = {15}, abstract = {The concrete is modeled as a material with damage and plasticity, whereat the viscoplastic and the viscoelastic behaviour depends on the rate of the total strains. Due to the damage behaviour the compliance tensor develops different properties in tension and compression. There have been tested various yield surfaces and flow rules, damage rules respectively to their usability in a concrete model. One three-dimensional yield surface was developed from a failure surface based on the Willam--Warnke five-parameter model by the author. Only one general uni-axial stress-strain-relation is used for the numeric control of the yield surface. From that curve all necessary parameters for different strengths of concrete and different strain rates can be derived by affine transformations. For the flow rule in the compression zone a non associated inelastic potential is used, in the tension zone a Rankine potential. Conditional on the time-dependent formulation, the symmetry of the system equations is maintained in spite of the usage of non-associated potentials for the derivation of the inelastic strains. In case of quasi statical computations a simple viscoplastic law is used that is rested on an approach to Perzyna. The principle of equality of dissipation power in the uni-axial and the three-axial state of stress is used. It is modified by a factor that depends on the actual stress ratio and in comparison with the Kupfer experiments it implicates strains that are more realistic. The implementation of the concrete model is conducted in a mixed hybrid finite element. Examples in the structural level are introduced for verification of the concrete model.}, subject = {Architektur }, language = {en} } @inproceedings{Klingert, author = {Klingert, Maik}, title = {THE USAGE OF IMAGE PROCESSING METHODS FOR INTERPRETATION OF THERMOGRAPHY DATA}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2977}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29777}, pages = {13}, abstract = {For assessment of old buildings, thermal graphic analysis aided with infra-red camera have been employed in a wide range nowadays. Image processing and evaluation can be economically practicable only if the image evaluation can also be automated to the largest extend. For that reason methods of computer vision are presented in this paper to evaluate thermal images. To detect typical thermal image elements, such as thermal bridges and lintels in thermal images respectively gray value images, methods of digital image processing have been applied, of which numerical procedures are available to transform, modify and encode images. At the same time, image processing can be regarded as a multi-stage process. In order to be able to accomplish the process of image analysis from image formation through perfecting and segmentation to categorization, appropriate functions must be implemented. For this purpose, different measuring procedures and methods for automated detection and evaluation have been tested.}, subject = {Architektur }, language = {en} } @inproceedings{KnauerDammeierMeffert, author = {Knauer, Uwe and Dammeier, T. and Meffert, Beate}, title = {THE STRUCTURE OF ROAD TRAFFIC SCENES AS REVEALED BY UNSUPERVISED ANALYSIS OF THE TIME AVERAGED OPTICAL FLOW}, editor = {G{\"u}rlebeck, Klaus and K{\"o}nke, Carsten}, organization = {Bauhaus-Universit{\"a}t Weimar}, doi = {10.25643/bauhaus-universitaet.2978}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170327-29780}, pages = {9}, abstract = {The Lucas-Kanade tracker has proven to be an efficient and accurate method for calculation of the optical flow. However, this algorithm can reliably track only suitable image features like corners and edges. Therefore, the optical flow can only be calculated for a few points in each image, resulting in sparse optical flow fields. Accumulation of these vectors over time is a suitable method to retrieve a dense motion vector field. However, the accumulation process limits application of the proposed method to fixed camera setups. Here, a histogram based approach is favored to allow more than a single typical flow vector per pixel. The resulting vector field can be used to detect roads and prescribed driving directions which constrain object movements. The motion structure can be modeled as a graph. The nodes represent entry and exit points for road users as well as crossings, while the edges represent typical paths.}, subject = {Architektur }, 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{OPUS4-749, title = {Tag des Baubetriebs 2006 - Tagungsbeitr{\"a}ge "Nachtragsmanagement in Praxis und Forschung"}, editor = {Professur Baubetrieb und Bauverfahren,}, doi = {10.25643/bauhaus-universitaet.749}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-7498}, year = {2006}, abstract = {Die Fachtagung richtete sich an Gesch{\"a}ftsf{\"u}hrer, Projektleiter, Bauleiter und Projektsteuerer in Planung und Ausf{\"u}hrung mit Beitr{\"a}gen zum Nachtrags- und {\"A}nderungsmanagement am Bau, Workflow-Management in der Baupraxis, Integration von Informationsprozessen auf der Basis von Nemetschek Technologien sowie Kompetenzaufbau durch gezielte Weiterbildung.}, subject = {Weimar / Bauhaus-Universit{\"a}t / Professur Baubetrieb und Bauverfahren}, language = {de} }