@inproceedings{AldaCremersBilek2004, author = {Alda, Sascha and Cremers, Armin B. and Bilek, Jochen}, title = {Support of Collaborative Structural Design Processes through the Integration of Peer-to-Peer and Multiagent Architectures}, doi = {10.25643/bauhaus-universitaet.148}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1481}, year = {2004}, abstract = {Structural engineering projects are increasingly organized in networked cooperations due to a permanently enlarged competition pressure and a high degree of complexity while performing the concurrent design activities. Software that intends to support such collaborative structural design processes implicates enormous requirements. In the course of our common research work, we analyzed the pros and cons of the application of both the peer-to-peer (University of Bonn) and multiagent architecture style (University of Bochum) within the field of collaborative structural design. In this paper, we join the benefits of both architecture styles in an integrated conceptual approach. We demonstrate the surplus value of the integrated multiagent-peer-to-peer approach by means of an example scenario in which several structural engineers are co-operatively designing the basic structural elements of an arched bridge, applying heterogeneous CAD systems.}, subject = {Ingenieurbau}, language = {en} } @inproceedings{BaranskiBoron2003, author = {Baranski, Jacek and Boron, Jacek}, title = {Computer Modeling of the Joints for WGP Construction Systems}, doi = {10.25643/bauhaus-universitaet.293}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-2935}, year = {2003}, abstract = {Poland is not situated in any seismic region of the earth, however there are still areas were underground mining is being conducted. In these areas, so-called 'paraseismic tremors', are very frequent phenomena. In the situation when a building examination is realized in order to define its safety, it is necessary to make a complete analysis, in which an influence of tremors should be included. To decide if a building is able to carry out any dynamic loads or not, it is necessary to compute its dynamic characteristics, i.e. natural frequencies. It is not possible using any standard techniques. After diagnosis a building in situ by an expert, computer techniques together with specialized software for dynamic, static, and strength analyses become a suitable tool. In this paper a special attention was paid to a typical twelve-store WGP (Wroclaw Great Plate) prefabricated building, concerning special type of joints. During dynamic actions these joints have a decisive influence on building's behavior. Paraseismic tremors are especially dangerous for these buildings and can be the reason of pre-failure states. It can be difficult and very expensive to prepare laboratory investigations of the part of a building or of a separate joint; therefore the computer modeling suitable to investigate behavior of such elements and whole buildings under different kinds of loads was used.}, subject = {Geb{\"a}ude}, language = {en} } @inproceedings{BergerGraeffWeinberg1997, author = {Berger, Hans and Graeff-Weinberg, K.}, title = {FEM-Detailuntersuchungen an Tragwerken unter Einsatz von pNh-{\"U}bergangselementen}, doi = {10.25643/bauhaus-universitaet.426}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-4267}, year = {1997}, abstract = {Detailuntersuchungen an Tragwerken f{\"u}hren bei FE-Berechnungen immer wieder auf das Problem einer geeigneten Netzgestaltung. W{\"a}hrend in weiten Bereichen ein grobes Netz ausreicht, muß an kritischen Stellen ein sehr feines Netz gew{\"a}hlt werden, um gerade dort hinreichend genaue Ergebnisse zu erhalten. Bei der Realisierung lokaler Netzverdichtungen stellt die Gestaltung des {\"U}bergangs vom groben zum feinen Netz das Hauptproblem dar. Im Beitrag wird hierzu eine Familie von FE-{\"U}bergangselementen vorgestellt, mit denen sich eine voll-kompatible Kopplung von wenigen großen Elementen mit vielen kleinen Elementen bereits {\"u}ber nur eine Stufe erzielen l{\"a}ßt. Diese neu entwickelten sogenannten pNh-Elemente erm{\"o}glichen an einer oder mehreren Seiten den Anschluß von N kleineren Elementen (Elementseiten f{\"u}r h-Verfeinerung). Das wird durch N st{\"u}ckweise definierte Ansatzfunktionen an den entsprechenden Seiten erreicht, wobei die Teilung nicht {\"a}quidistant sein braucht. Dar{\"u}ber hinaus ist es m{\"o}glich, Elemente unterschiedlichen Polynomgrades p an den Standardseiten und den Verfeinerungsseiten anzuschließen. Der praktische Einsatz der {\"U}bergangselemente setzt geeignete automatische oder halbautomatische Netzgeneratoren voraus, die diese Elemente einbeziehen. Im Rahmen einer substrukturorientierten Modellierung l{\"a}ßt sich dies besonders g{\"u}nstig realisieren. Im Beitrag wird gezeigt, wie durch Zerlegung des Gesamtmodells in Bereiche mit grobem Netz, mit {\"U}bergangsnetz und mit feinem Netz, eine effektive Generierung der Netzverdichtungen zu erreichen ist. An einem praktischen Beispiel aus dem Bauingenieurwesen werden die Vorteile des vorgestellten {\"U}bergangselementkonzeptes umfassend demonstriert.}, subject = {Tragwerk}, language = {de} } @inproceedings{BoukampAkinci2004, author = {Boukamp, Frank and Akinci, Burcu}, title = {Towards Automated Defect Detection: Object-oriented Modeling of Construction Specifications}, doi = {10.25643/bauhaus-universitaet.131}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1315}, year = {2004}, abstract = {This paper describes an ongoing research on the representation and reasoning about construction specifications, which is part of a bigger research project that aims at developing a formalism for automating the identification of deviations and defects on construction sites. We specifically describe the requirements on product and process models and an approach for representing and reasoning about construction specifications to enable automated detection and assessment of construction deviations and defects. This research builds on the previous research on modeling design specifications and extends and elaborates concept of contexts developed in that domain. The paper provides an overview of how the construction specifications are being modele d in this research and points out future steps that need to be accomplished to develop the envisioned automated deviation and defect detection system.}, subject = {Bauwerk}, language = {en} } @inproceedings{EslimyIsfahanyPegels2004, author = {Eslimy-Isfahany, S. H. R. and Pegels, Georg}, title = {Net-distributed Co-operation Including Developing Countries, Practical Case Study - Iran}, doi = {10.25643/bauhaus-universitaet.142}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1421}, year = {2004}, abstract = {The scientific transfer of key technology features to developing countries, together with adequate competence, localisation and adaptation, is the primary purpose of the proposed investigation. It is evident that introducing high-level CAD design and detailing will improve the planning process in developing countries. Successful utilization of applied information technology for the planning process, however, depends on the user-interface of individual software. Therefore, to open the great opportunity embedded in CAD software for clients globally, the language and character-set barrier of traditional user-interfaces must be overcome. A proposal for a research program is given here to address such issue in favour of global civil engineering.}, subject = {Ingenieurbau}, language = {en} } @inproceedings{Gasser2003, author = {Gasser, Ingenuin}, title = {On A New One-Dimensional Model to Describe Tunnel Fires}, doi = {10.25643/bauhaus-universitaet.288}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-2889}, year = {2003}, abstract = {We present a model derived to describe tunnel fires. The model originates in a compressible description of the air in the tunnel. It takes into account the strong buoyancy forces and at the same time the small Mach-number of the airflow. We comment on the derivation, on analytical results and on numerical simulations of the model. The model has been validated using data from real tunnel fire experiments. It shows good agreement with the real situation.}, subject = {Tunnel}, language = {en} } @inproceedings{GebbekenBaumhauerIonita2004, author = {Gebbeken, Norbert and Baumhauer, Andreas and Ionita, Mihai}, title = {Increasing the Reliability and Performance through Automatization and Parallel Working}, doi = {10.25643/bauhaus-universitaet.139}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1397}, year = {2004}, abstract = {Re-examination of the behaviour of structures can be necessary due to deterioration or changes in the traffic situation during their lifetime. The Finite Element Method (FEM) is widely used in order to accomplish numerical analysis. Considering the development of computer performance, more detailed FEM models can be analyzed, even on site, with mobile computers. To compensate the increasing amount of data needed for the model input, measures need to be taken to save time, by distributing the work. In order to provide consistency to the model, fedback data must be checked upon reception. A local wireless computer network of ultra-portable devices linked together with a computer can provide the coordination necessary for efficient parallel working. Based on a digital model consisting of all data gathered, structural modelling and numerical analysis are performed automatically. Thus, the user is released from the work that can be automatized and the time needed for the overall analysis of a structure is decreased.}, subject = {Ingenieurbau}, language = {en} } @inproceedings{GrigrievaLymarenko2003, author = {Grigrieva, Polina and Lymarenko, Yulia}, title = {Mathematical modeling of nonlinear effects for vibrodiagnostics of fatigue cracks}, doi = {10.25643/bauhaus-universitaet.291}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-2917}, year = {2003}, abstract = {The vibration control of complicated mechanical structures is impossible without proper mathematical models that allow to have a true apprehension of events occurring in structural member before the starting of the experiment and correct the diagnostic experiment in case of need. An approach that implies using of a discrete model reflecting all required features of a prototype system and permitting of an effective analytical and numerical investigation is proposed in the work. At first a discrete model of a bladed disk with flaw is considered. Taking into account the symmetry of the structure by utilization of mathematical tools of group presentation theory the number of degrees of freedom of the system is diminished. Small damage of the disk is regarded as perturbation of structure symmetry. The distinction of vibration characteristics such as natural frequencies and mode shapes of damaged and undamaged systems is determined theoretically with the help of perturbation theory and can be used as an effective diagnostic criterion of a small-scale damage of the structure. In the second part of the work a non-linear two-mass model of an acoustic emission in a damaged structure is proposed. On basis of the numerical integration of the nonlinear differential equations and expansion of the derived solution into a Fourier series free and forced vibrations of the model are investigated. It is shown that proposed model reflects all characteristic properties of vibrations of damaged structures: reduction of natural frequency, sub- and super-resonances, acoustic effects.}, subject = {Nichtlineare Mechanik}, language = {en} } @inproceedings{HahnWeitzmann2003, author = {Hahn, Stephan and Weitzmann, R{\"u}diger}, title = {Nichtlineare Analyse von hybriden Konstruktionen unter Verwendung von selektiv gekoppelten Tragwerks- und Querschnittsmodellen}, doi = {10.25643/bauhaus-universitaet.302}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-3026}, year = {2003}, abstract = {Bei der Untersuchung hybrider Strukturen kann eine Kopplung von Modellen unterschiedlicher Modellebenen vorteilhaft sein. Durch selektive Kopplung von Tragwerks- und Querschnittsmodellen in ausgew{\"a}hlten Bereichen der Konstruktion kann z.B. eine Verbesserung der Abbildungsgenauigkeit erzielt werden. Dadurch werden erweiterte Aussagen {\"u}ber das Querschnittstragverhalten in extrem beanspruchten Teilen des Tragwerks bei optionaler Skalierbarkeit des Modellumfangs m{\"o}glich. Im Beitrag werden ausgew{\"a}hlte Varianten der Modellbildung gegen{\"u}bergestellt und bewertet. Hierbei werden Aspekte der physikalischen Nichtlinearit{\"a}t von hybriden Konstruktionen insbesondere von Stahlbetonkonstruktionen ber{\"u}cksichtigt. Die Einbeziehung von Verfahren der mathematischen Optimierung in die Berechnungsstrategie erm{\"o}glicht die L{\"o}sung der zugrunde liegenden nichtlinearen Problemstellungen unter Vorgabe von Bemessungszielen und unter Beachtung von Grenzzustandsbedingungen.}, subject = {Tragwerk}, language = {de} } @inproceedings{HartmannMeissnerRueppel2004, author = {Hartmann, Dietrich and Meißner, Udo F. and Rueppel, Uwe}, title = {Integration of Productmodel Databases into Multi-Agent Systems}, doi = {10.25643/bauhaus-universitaet.141}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20111215-1410}, year = {2004}, abstract = {This paper deals with two different agent-based approaches aimed at the incorporation of complex design information into multi-agent planning systems. The first system facilitates collaborative structural design processes, the second one supports fire engineering in buildings. Both approaches are part of two different research projects that belong to the DFG1 priority program 1103 entitled "Network-based Co-operative Planning Processes in Structural Engineering" (DFG 2000). The two approaches provide similar database wrapper agents to integrate relevant design information into two multi-agent systems: Database wrapper agents make the relevant product model data usable for further agents in the multi-agent system, independent on their physical location. Thus, database wrapper agents act as an interface between multi-agent system and heterogeneous database systems. The communication between the database wrapper agents and other requesting agents presumes a common vocabulary: a specific database ontology that maps database related message contents into database objects. Hereby, the software-wrapping technology enables the various design experts to plug in existing database systems and data resources into a specific multi-agent system easily. As a consequence, dynamic changes in the design information of large collaborative engineering projects are adequately supported. The flexible architecture of the database wrapper agent concept is demonstrated by the integration of an XML and a relational database system.}, subject = {Ingenieurbau}, language = {en} }