@incollection{Hartmann, author = {Hartmann, Frank}, title = {Zwischen Leibniz und Google - Otlet der Weltbibliothekar}, series = {Vom Buch zur Datenbank. Paul Otlets Utopie der Wissensvisualisierung}, booktitle = {Vom Buch zur Datenbank. Paul Otlets Utopie der Wissensvisualisierung}, publisher = {Avinus}, address = {Berlin}, doi = {10.25643/bauhaus-universitaet.2268}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20140811-22685}, pages = {11 -- 61}, abstract = {Gegen Ende des 19. Jahrhunderts geriet das Dokumentationswesen in eine Krise: wie l{\"a}sst sich das kulturelle Wissen nachhaltiger organisieren? Paul Otlet (1868-1944), ein belgischer Industriellenerbe und studierter Rechtsanwalt, entwickelte zusammen mit Henri La Fontaine ab 1895 ein Ordnungs- und Klassifikationssystem, das das millionenfach publizierte „Weltwissen" dokumentieren sollte. Otlets Anspruch war die Schaffung eines „Instrument d'ubiquit{\´e}", das zur „Hyper-Intelligence" f{\"u}hren sollte. Jahrzehnte vor Web und Wikis weisen diese Ideen auf eine globale Vernetzung des Wissens hin. Der vorliegende Titel erinnert an den Pionier Paul Otlet mit einer ausf{\"u}hrlichen Einleitung von Frank Hartmann (Bauhaus-Universit{\"a}t Weimar), Beitr{\"a}gen von W. Boyd Rayward (University of Illinois), Charles van den Heuvel (K{\"o}niglich Niederl{\"a}ndische Akademie der Wissenschaften) und Wouter Van Acker (Universit{\"a}t Gent).}, subject = {philosophy}, language = {de} } @inproceedings{LahmerGhorashi, author = {Lahmer, Tom and Ghorashi, Seyed Shahram}, title = {XFEM-BASED CRACK IDENTIFICATION APPLYING REGULARIZING METHODS IN A MULTILEVEL APPROACH}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2771}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27717}, pages = {9}, abstract = {Many structures in different engineering applications suffer from cracking. In order to make reliable prognosis about the serviceability of those structures it is of utmost importance to identify cracks as precisely as possible by non-destructive testing. A novel approach (XIGA), which combines the Isogeometric Analysis (IGA) and the Extended Finite Element Method (XFEM) is used for the forward problem, namely the analysis of a cracked material, see [1]. Applying the NURBS (Non-Uniform Rational B-Spline) based approach from IGA together with the XFEM allows to describe effectively arbitrarily shaped cracks and avoids the necessity of remeshing during the crack identification problem. We want to exploit these advantages for the inverse problem of detecting existing cracks by non-destructive testing, see e.g. [2]. The quality of the reconstructed cracks however depends on two major issues, namely the quality of the measured data (measurement error) and the discretization of the crack model. The first one will be taken into account by applying regularizing methods with a posteriori stopping criteria. The second one is critical in the sense that too few degrees of freedom, i.e. the number of control points of the NURBS, do not allow for a precise description of the crack. An increased number of control points, however, increases the number of unknowns in the inverse analysis and intensifies the ill-posedness. The trade-off between accuracy and stability is aimed to be found by applying an inverse multilevel algorithm [3, 4] where the identification is started with short knot vectors which successively will be enlarged during the identification process.}, subject = {Angewandte Informatik}, language = {en} } @article{Kalisch, author = {Kalisch, Dominik}, title = {Wissen wer wo wohnt}, doi = {10.25643/bauhaus-universitaet.2669}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20160822-26695}, abstract = {In cities people live together in neighbourhoods. Here they can find the infrastructure they need, starting with shops for the daily purpose to the life-cycle based infrastructures like kindergartens or nursing homes. But not all neighbourhoods are identical. The infrastructure mixture varies from neighbourhood to neighbourhood, but different people have different needs which can change e.g. based on the life cycle situation or their affiliation to a specific milieu. We can assume that a person or family tries to settle in a specific neighbourhood that satisfies their needs. So, if the residents are happy with a neighbourhood, we can further assume that this neighbourhood satisfies their needs. The socio-oeconomic panel (SOEP) of the German Institute for Economy (DIW) is a survey that investigates the economic structure of the German population. Every four years one part of this survey includes questions about what infrastructures can be found in the respondents neighbourhood and the satisfaction of the respondent with their neighbourhood. Further, it is possible to add a milieu estimation for each respondent or household. This gives us the possibility to analyse the typical neighbourhoods in German cities as well as the infrastructure profiles of the different milieus. Therefore, we take the environment variables from the dataset and recode them into a binary variable - whether an infrastructure is available or not. According to Faust (2005), these sets can also be understood, as a network of actors in a neighbourhood, which share two, three or more infrastructures. Like these networks, this neighbourhood network can also be visualized as a bipartite affiliation network and therefore analysed using correspondence analysis. We will show how a neighbourhood analysis will benefit from an upstream correspondence analysis and how this could be done. We will also present and discuss the results of such an analysis.}, subject = {urban planning}, language = {de} } @inproceedings{AhmadZabelKoenke, author = {Ahmad, Sofyan and Zabel, Volkmar and K{\"o}nke, Carsten}, title = {WAVELET-BASED INDICATORS FOR RESPONSE SURFACE MODELS IN DAMAGE IDENTIFICATION OF STRUCTURES}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2758}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170306-27588}, pages = {14}, abstract = {In this paper, wavelet energy damage indicator is used in response surface methodology to identify the damage in simulated filler beam railway bridge. The approximate model is addressed to include the operational and surrounding condition in the assessment. The procedure is split into two stages, the training and detecting phase. During training phase, a so-called response surface is built from training data using polynomial regression and radial basis function approximation approaches. The response surface is used to detect the damage in structure during detection phase. The results show that the response surface model is able to detect moderate damage in one of bridge supports while the temperatures and train velocities are varied.}, subject = {Angewandte Mathematik}, language = {en} } @article{TonnTatarin, author = {Tonn, Christian and Tatarin, Ren{\´e}}, title = {Volumen Rendering in der Architektur: {\"U}berlagerung und Kombination von 3D Voxel Volumendaten mit 3D Geb{\"a}udemodellen}, doi = {10.25643/bauhaus-universitaet.2671}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20160822-26718}, abstract = {Volumerendering ist eine Darstellungstechnik, um verschiedene r{\"a}umliche Mess- und Simulationsdaten anschaulich, interaktiv grafisch darzustellen. Im folgenden Beitrag wird ein Verfahren vorgestellt, mehrere Volumendaten mit einem Architekturfl{\"a}chenmodell zu {\"u}berlagern. Diese komplexe Darstellungsberechnung findet mit hardwarebeschleunigten Shadern auf der Grafikkarte statt. Im Beitrag wird hierzu der implementierte Softwareprototyp "VolumeRendering" vorgestellt. Neben dem interaktiven Berechnungsverfahren wurde ebenso Wert auf eine nutzerfreundliche Bedienung gelegt. Das Ziel bestand darin, eine einfache Bewertung der Volumendaten durch Fachplaner zu erm{\"o}glichen. Durch die {\"U}berlagerung, z. B. verschiedener Messverfahren mit einem Fl{\"a}chenmodell, ergeben sich Synergien und neue Auswertungsm{\"o}glichkeiten. Abschließend wird anhand von Beispielen aus einem interdisziplin{\"a}ren Forschungsprojekt die Anwendung des Softwareprototyps illustriert.}, subject = {Multiple Volume Rendering}, language = {de} } @phdthesis{Wieteska, author = {Wieteska, Marcin}, title = {Untersuchungen zur Optimierung des Feuerwiderstandsverhaltens von Gipsplatten}, publisher = {Marcin Wieteska}, address = {Warszawa}, isbn = {978-83-936473-0-9}, doi = {10.25643/bauhaus-universitaet.1782}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20121207-17829}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {176}, abstract = {Die Qualit{\"a}t von Beplankungselementen wirkt sich deutlich auf den Feuerwiderstand von Metallst{\"a}nder-Wandkonstruktionen aus. Daher wurde im Rahmen dieser Arbeit der Einfluss von Zus{\"a}tzen in Gipsplatten bez{\"u}glich einer m{\"o}glichen Verbesserung dieser Eigenschaft untersucht. Zu diesem Zweck wurden spezielle, den jeweiligen Untersuchungsbedingungen angepasste Probek{\"o}rper unter Verwendung verschiedenster Zus{\"a}tze gefertigt. Die Beurteilung deren Auswirkungen erfolgte insbesondere mittels nachfolgender f{\"u}nf Kriterien: 1) dem Zeitpunkt der Temperaturerh{\"o}hung nach der Probek{\"o}rperentw{\"a}sserung, 2) dem Maximalwert der Plattenr{\"u}ckseitentemperatur, 3) der Gr{\"o}ße und der Anzahl der Risse, 4) der Plattenstabilit{\"a}t nach der W{\"a}rmebeanspruchung, 5) der Verk{\"u}rzung von prismatischen Probek{\"o}rpern. Besonders wichtig war hierbei die Charakterisierung der Auswirkungen einer simulierten Brandbeanspruchung von 970 °C {\"u}ber 90 Minuten auf Labor-Gipsplatten. Dabei wurde die Temperatur{\"a}nderung auf der Plattenr{\"u}ckseite {\"u}ber den gesamten Pr{\"u}fzeitraum kontinuierlich erfasst. Die Bewertung des Zusammenhalts der Platten nach der thermischen Beanspruchung erfolgte erstmals quantitativ {\"u}ber Anzahl und Gr{\"o}ße der an den Proben entstandenen Risse. Urs{\"a}chlich f{\"u}r die Rissbildung ist die Verringerung des Probek{\"o}rpervolumens infolge des ausgetriebenen Kristallwassers. Da dieser Parameter im Plattenversuch nicht bestimmt werden kann, wurde erg{\"a}nzend das L{\"a}ngen{\"a}nderungsverhalten von Prismen im Ergebnis einer 90min{\"u}tigen Temperung bei 1000 °C im Muffelofen ermittelt. Besonders vorteilhaft hat sich die Zugabe von 80 g/m2 Glasfasern und 7,75 \% Kalksteinmehl auf das Verhalten von Gipsplatten bei Brandbeanspruchung ausgewirkt. Diese Verbesserung ist insbesondere auf h{\"o}here Stabilit{\"a}t und geringere Schrumpfung der Gipsplatte zur{\"u}ckzuf{\"u}hren. Basierend auf den im Labormaßstab erhaltenen Ergebnissen wurden Rezepturvorschl{\"a}ge zur Verbesserung des Feuerwiderstandsverhaltens von Gipsplatten unter Praxisbedingungen entwickelt. Die Herstellung der erforderlichen großformatigen Platten erfolgte auf der Bandstraße der Knauf Gips KG. Diese Platten wurden als Wandkonstruktion mit zweilagiger Beplankung einer großtechnischen Pr{\"u}fung erfolgreich unterzogen. Eine geringere Durchbiegung der Wandkonstruktion, eine verminderte Volumenreduzierung der Platten sowie eine erh{\"o}hte Plattenstabilit{\"a}t belegen die verbesserten Eigenschaften dieser modifizierten Feuerschutzplatte. Weitere durchgef{\"u}hrte Untersuchungen ergaben, dass es unerheblich ist, ob die Platten auf Basis von Natur- oder REA-Gips bzw. mit hohem oder niedrigem Fl{\"a}chengewicht gefertigt wurden. Das eindeutig beste Ergebnis mit einer Feuerwiderstandsdauer von 118 Minuten hat eine Wandkonstruktion aus Feuerschutzplatten auf Basis eines Stuckgipses aus 100 \% REA-Gips mit einem Anteil von 83,9 g/m2 Glasfasern und 1 \% Vermiculit und einem Fl{\"a}chengewicht von 10,77 kg/m2, bei einer Plattenst{\"a}rke von 12,5 mm. Die als Ziel vorgebende Feuerwiderstandsdauer von 120 Minuten bei zweilagiger Beplankung ohne D{\"a}mmstoff k{\"o}nnte k{\"u}nftig erreicht werden, wenn es gelingt, die Volumenreduzierung noch besser zu kompensieren und die Plattenstabilit{\"a}t zu steigern. Eine M{\"o}glichkeit hierzu ist die Substitution der beidseitigen Kartonlagen durch eine Glasfaser-Vliesummantelung. Die Wandkonstruktion W112 ohne D{\"a}mmstoff erreicht dabei eine Feuerwiderstandsdauer von weit {\"u}ber 120 Minuten, wobei der Gipskern mit Glasfasern armiert ist.}, subject = {0947}, language = {de} } @masterthesis{Marwitz2011, type = {Bachelor Thesis}, author = {Marwitz, Simon Jakob}, title = {Untersuchungen zur optimalen Sensorpositionierung bei der experimentellen Modalanalyse}, doi = {10.25643/bauhaus-universitaet.1531}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20120128-15311}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {70}, year = {2011}, abstract = {Experimentelle Untersuchung eines Verfahrens zur optimalen Positionierung von Referenzsensoren bei der experimentellen Modalanalyse mit output-only Methoden nach Brehm (2011). Untersuchung des Einflusses der Referenzsensorpositionierung, -anzahl und der Positionierung der wandernden Sensoren unter Anwendung des Stochastic-Subspace-Verfahrens zur Auswertung der output-only Messdaten.}, subject = {Modalanalyse}, language = {de} } @phdthesis{Schneider, author = {Schneider, Jens}, title = {Untersuchungen zum Alterungsverhalten und zur Langzeitstabilit{\"a}t von Y-TZP/Al2O3-Dispersionskeramiken (ATZ) f{\"u}r die Anwendung in der H{\"u}ft-Endoprothetik}, doi = {10.25643/bauhaus-universitaet.1776}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20121130-17761}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {151}, abstract = {6 Zusammenfassung und Ausblick Die hydrothermal induzierte Phasentransformation konnte f{\"u}r ATZ-Keramik mit tiefenge-mittelten und tiefenaufgel{\"o}sten Methoden charkterisiert und quantifiziert werden. Die zeit- und temperaturabh{\"a}ngige Alterungskinetik von ATZ wurde durch neun Tempera-turstufen in einem Temperaturbereich von 50 °C bis 134 °C untersucht und die kinetischen Parameter nummerisch bestimmt. F{\"u}r 3Y-TZP wurde diese Prozedur bei drei Temperaturen im Temperaturbereich von 70 °C bis 134 °C angewendet. Aufgrund des ARRHENIUS-Verhaltens der Umwandlungskinetik konnte der zeitliche Verlauf der isotherm stattfinden-den hydrothermal induzierten Phasentransformation bei K{\"o}rpertemperatur simuliert wer-den. Die Simulation dient zur Bewertung der Langzeitstabilit{\"a}t von medizinischen Implanta-ten aus ATZ bzw. 3Y-TZP. Die Untersuchungen wurden in Wasser und in Wasserdampf bzw. wasserdampfges{\"a}ttigter Luft durchgef{\"u}hrt. Die Langzeitsimulation f{\"u}r 3Y-TZP wurde an-hand von Explantat-Untersuchungen verifiziert. ATZ zeigt gegen{\"u}ber 3Y-TZP eine h{\"o}here Alterungsstabilit{\"a}t bezogen auf die zeitliche Ent-wicklung der monoklinen Phase. Im Hinblick auf die Oberfl{\"a}chenh{\"a}rte, die durch die Pha-senumwandlung stark beeinflusst wird, erweist sich ATZ {\"u}ber einen langen Alterungszeit-raum stabiler als 3Y-TZP. Bis zu einem monoklinen Gehalt von 40 \% beweist ATZ einen deutlichen H{\"a}rtevorteil gegen{\"u}ber 3Y TZP, dieser entspricht in der Langzeitsimulation f{\"u}r die Wasserlagerung ca. 35 Jahre. Das wirkt sich insbesondere bei Verschleißpaarungen wie beim k{\"u}nstlichen H{\"u}ftgelenk positiv aus. Verschleißuntersuchungen an einer neu entwickelten Kugel-auf-Scheibe-Geometrie mit li-nearer Kinematik, die dem H{\"u}ftgelenk nachempfunden wurde, belegen die vorteilhaften Verschleißeigenschaften von ATZ in Form von sehr geringen Abtragsraten und einer intak-ten Oberfl{\"a}che nach 720 000 absolvierten Zyklen. Dabei wurde sogar eine Aufh{\"a}rtung der Oberfl{\"a}che durch die Verschleißbeanspruchung um bis zu 8 \% nachgewiesen. Bei der tiefengemittelten Charakterisierung der hydrothermalen Alterung wurde in beiden Materialtypen festgestellt, dass die Geschwindigkeit der Phasentransformation neben der Temperatur merklich von der {\"A}nderung der H2O-Stoffmengenkonzentrantion an der Ober-fl{\"a}che der Keramik abh{\"a}ngig ist, was sich mit den unterschiedlichen Aktivierungsenergien f{\"u}r Wasser- bzw. Wasserdampflagerung belegen l{\"a}sst. Die Aktivierungsenergie Ea der hyd-rothermalen Phasentransformation wurde mit Hilfe der ARRHENIUS-Beziehung ermittelt und betr{\"a}gt f{\"u}r ATZ bei Wasserdampflagerung 102 kJ/mol und bei Wasserlagerung 92 kJ/mol. F{\"u}r Y-TZP betr{\"a}gt die Aktivierungsenergie 114 kJ/mol bei Wasserdampflagerung und 102 kJ/mol bei Wasserlagerung. Der resultierende pr{\"a}exponentielle Faktor k0 unterscheidet sich f{\"u}r Wasserlagerung und Wasserdampflagerung um eine Gr{\"o}ßenordnung, was auf einen leicht andersartigen thermisch aktivierten Gesamtprozess hinweist. Der Avrami-Exponent n, der einen Hinweis auf den Mechanismus der Keimbildung sowie deren geometrische Ordnung geben kann, zeigte keine signifikante Abh{\"a}ngigkeit von der Temperatur und vom Umgebungsmedium. Er ist dagegen zeitabh{\"a}ngig und f{\"a}llt mit zuneh-mender Alterungszeit, d.h. mit zunehmendem monoklinem Gehalt von ca. 4 auf 0,5 ab, was auf eine abnehmende Keimbildungsrate hindeutet. In Verbindung mit weiteren Untersu-chungen durch unabh{\"a}ngige und zum Teil tiefenaufl{\"o}sende Methoden wie GIXRD, NRA und Knoop-Mikroh{\"a}rte-Messungen l{\"a}sst sich der Alterungsmechanismus, bzw. sein zeitlicher und {\"o}rtlicher Ablauf, durch die drei Stadien A, B und C beschreiben: A 0-5 ma. \% m-ZrO2 Quasi-homogene Keimbildung an bevorzugten Orten wie Kornkan-ten und Kornecken (n≈4), Wassertransport wahrscheinlich via Korngrenzendiffusion, Aufh{\"a}rtung der Oberfl{\"a}che B 5-40 ma. \% m-ZrO2 Keimbildung an den Korngrenzfl{\"a}chen bis zur Keims{\"a}ttigung (n≈2), monokline Randschicht w{\"a}chst zeitlich linear, Wassertransport konvektiv {\"u}ber Mikrorisse, deutlicher H{\"a}rteverlust der Oberfl{\"a}che C ≥ 40 ma. \% m-ZrO2 Wachstum der monoklinen Kristallite von den Korngrenzfl{\"a}chen in die tetragonalen Kristallite unter starker Verzwillingung (n≈0,5), Abnahme der tetragonalen Kristallitgr{\"o}ße, starke Mikrorissbildung, dramatischer R{\"u}ckgang der Oberfl{\"a}chenh{\"a}rte Die Kristallitgr{\"o}ße der monoklinen Phase verbleibt im ATZ {\"u}ber alle drei Abschnitte bei 30 ±5 nm. Ein Anwachsen der Kristallite ist mechanische behindert. Kleinere monokline Kristallite sind im ATZ thermodynamisch instabil. Die Kristallitgr{\"o}ße der tetragonalen Phase f{\"a}llt in den Abschnitten A und B sehr langsam und in C sehr schnell bis auf 25 nm ab. Bei dieser Kristallitgr{\"o}ße ist die tetragonale Phase gegen{\"u}ber der monoklinen Phase thermody-namisch stabil. Diese residualen tetragonalen Kristallite weisen nach vollst{\"a}ndigem Reakti-onsablauf einem Anteil von 7 ma. \% auf. Der S{\"a}ttigungsgehalt der monoklinen Phase betrug in beiden Materialen unabh{\"a}ngig von der Temperatur bzw. dem Umgebungsmedium 75 \% der ZrO2-Phase. In Abschnitt C besitzt die residuale tetragonale Phase eine starke Orientierung. Dadurch wird die geometrische Bedingtheit der hydrothermal induzierten Phasenumwandlung ver-deutlicht. Die monokline Phase ist {\"u}ber den gesamten Alterungsprozess stark nach m(1 1  1) orientiert, was mit einer bevorzugten Umklapprichtung der c-Achse zur freien Oberfl{\"a}che hin verbunden ist. Mit Hilfe der tiefenaufgel{\"o}sten Phasenanalyse konnte die Wachstumsgeschwindigkeit der monoklinen Randschicht von der Oberfl{\"a}che in das Volumen untersucht werden. Die Ge-schwindigkeit des Schichtwachstums ist in Abschnitt B nicht zeit- und tiefenabh{\"a}ngig, son-dern konstant mit ausgepr{\"a}gtem ARRHENIUS-Verhalten (Temperaturabh{\"a}ngigkeit). Die Akti-vierungsenergie der Schichtwachstumsgeschwindigkeit km liegt in der gleichen Gr{\"o}ßenord-nung wie die der Transformationskonstante k. Die Umwandlungszone schreitet also mit konstanter Geschwindigkeit in das Volumen fort und hinterl{\"a}sst ein verzweigtes Mikro- und Nanoriss-System. FESEM-Aufnahmen best{\"a}tigen das Vorhandensein einer por{\"o}sen Randschicht, durch die das Wasser nahezu ungehindert eindringen kann. NRA Untersuchungen deuten in Stadium A auf Korngrenzendiffusion hin und best{\"a}tigen in Stadium B einen konvektiven Transport des Wassers an die Transformationszone. Eine Dif-fusion {\"u}ber Sauerstoffleerstellen im Gitter konnte anhand von Proben aus 8YSZ nicht nach-gewiesen werden. Dagegen kommt es in dem verzweigten Riss- und Porensystem in der gealterten Randschicht zum R{\"u}cktransport des Wassers an die Oberfl{\"a}che, sobald die Pro-ben aus der hydrothermalen Atmosph{\"a}re genommen, an Luft gelagert oder in die Hochva-kuumkammer der NRA-Messapparatur eingeschleust werden. Mikrostrukturelle Untersuchungen an eigens entwickelten Verschleißpaarungen zeigten nach 720000 Zyklen {\"a}hnliche Oberfl{\"a}cheneigenschaften wie im Alterungsstadium A. Man kann daher davon ausgehen, dass die Stadien B und C aus Stabilit{\"a}tsgr{\"u}nden in der tribolo-gischen Kontaktzone nicht existieren k{\"o}nnen und es dass sich im Falle einer gleichzeitigen, hydrothermalen und tribologischen Beanspruchung um einen station{\"a}ren Alterungs- und Verschleißprozess handelt. Durch quasiplastische Deformation der monoklinen und tetra-gonalen Kristallite wird die Verschleißrate und die Abriebpartikel bei einer hart /hart Paa-rung aus ATZ deutlich minimiert, so dass ATZ f{\"u}r die H{\"u}ftendoprothetik ein durchaus geeig-neten Werkstoff darstellt, der sich auf der Grundlage der in dieser Arbeit gewonnenen Daten {\"u}ber eine Imlantationsdauer von .mehr als 15 Jahre stabil verhalten kann.}, subject = {Dispersionskeramik}, language = {de} } @phdthesis{Posern, author = {Posern, Konrad}, title = {Untersuchungen von Magnesiumsulfat-Hydraten und Sulfat/Chlorid-Mischungen f{\"u}r die Eignung als Aktivstoff in Kompositmaterialien f{\"u}r die thermochemische W{\"a}rmespeicherung}, doi = {10.25643/bauhaus-universitaet.1678}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20120704-16784}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {105}, abstract = {Die thermochemische W{\"a}rmespeicherung {\"u}ber reversible Salzhydratation stellt einen aussichtsreichen Weg zur Speicherung von Niedertemperaturw{\"a}rme, wie z.B. solarer Energie, dar. Untersuchungen an Magnesiumsulfat-Hydraten zeigen, dass das bei 130°C entw{\"a}sserte Magnesiumsulfat-Heptahydrat seinen thermodynamisch stabilen Endzustand w{\"a}hrend der Reaktion mit gasf{\"o}rmigem Wasser nicht wieder erreicht. Um diese kinetische Hemmung zu {\"u}berwinden und den Einfluss von unterschiedlichen Porenr{\"a}umen auf die Hydratation bzw. Sorption des Magnesiumsulfates zu charakterisieren, wurde das Magnesiumsulfat in Tr{\"a}germaterialien auf Basis offenporiger Gl{\"a}ser mit durchschnittlichen Porendurchmessern von 4 nm bis 1,4 µm eingebracht und diese Kompositmaterialien untersucht. Dabei ist festgestellt worden, dass jede salzbezogene Sorptionsw{\"a}rme im Porenraum h{\"o}her ist, als die des ungetr{\"a}gerten Salzes und mit kleiner werdendem Porenradius weiter zunimmt. Weiterhin wurden Teile des Magnesiumsulfates mit niedrig deliqueszierenden Salzen substituiert, um die Wasseraufnahme und somit die W{\"a}rmespeicherkapazit{\"a}t zu erh{\"o}hen. Dies stellt einen neuen Weg zur Herstellung von Kompositmaterialien dar, {\"u}ber den man Eigenschaften wie Deliqueszenzfeuchte und Desorptionstemperatur einstellen und an die Sorptionsbedingungen eines Speichers anpassen kann. Als niedrig deliqueszierende Salze wurden Magnesiumchlorid und Lithiumchlorid als Zus{\"a}tze untersucht, wobei ein Ansteigen der Sorptionsw{\"a}rme und Wasseraufnahme mit steigendem Chloridanteil festgestellt wurde. Aufgrund der geringeren Deliqueszenzfeuchte des Lithiumchlorides gegen{\"u}ber dem Magnesiumchlorid wurden bei gleichen Massenverh{\"a}ltnissen h{\"o}here Sorptionsw{\"a}rmen erzielt. Untersuchungen zu Zinksulfat in Verbindung mit Chloriden bescheinigen diesem Salz -speziell bei tieferen Entw{\"a}sserungstemperaturen- eine gute Eignung als Aktivstoff zur W{\"a}rmespeicherung. Zusammenfassend konnte festgestellt werden, dass sich die W{\"a}rmespeicherkapazit{\"a}ten {\"u}ber die Porengr{\"o}ße, in die das Salz eingebracht wird, und die gew{\"a}hlte Mischungszusammensetzung steuern lassen. Die gemessenen Sorptionsw{\"a}rmen erm{\"o}glichen insbesondere bei niedrigen Sorptionstemperaturen und hohen Luftfeuchtigkeiten den Schluss, dass die Verwendung von Salzmischungen als Aktivkomponente in Kompositmaterialien einen geeigneten Weg zur thermochemischen Speicherung solarer W{\"a}rme (≤130 °C) darstellt.}, subject = {Thermische Energiespeicherung}, language = {de} } @inproceedings{MotraDimmigOsburgHildebrand, author = {Motra, Hem Bahadur and Dimmig-Osburg, Andrea and Hildebrand, J{\"o}rg}, title = {UNCERTAINTY QUANTIFICATION IN CYCLIC CREEP PREDICTION OF CONCRETE}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2780}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27803}, pages = {18}, abstract = {This paper presents a methodology for uncertainty quantification in cyclic creep analysis. Several models- , namely BP model, Whaley and Neville model, modified MC90 for cyclic loading and modified Hyperbolic function for cyclic loading are used for uncertainty quantification. Three types of uncertainty are included in Uncertainty Quantification (UQ): (i) natural variability in loading and materials properties; (ii) data uncertainty due to measurement errors; and (iii) modelling uncertainty and errors during cyclic creep analysis. Due to the consideration of all type of uncertainties, a measure for the total variation of the model response is achieved. The study finds that the BP, modified Hyperbolic and modified MC90 are best performing models for cyclic creep prediction in that order. Further, global Sensitivity Analysis (SA) considering the uncorrelated and correlated parameters is used to quantify the contribution of each source of uncertainty to the overall prediction uncertainty and to identifying the important parameters. The error in determining the input quantities and model itself can produce significant changes in creep prediction values. The variability influence of input random quantities on the cyclic creep was studied by means of the stochastic uncertainty and sensitivity analysis namely the Gartner et al. method and Saltelli et al. method. All input imperfections were considered to be random quantities. The Latin Hypercube Sampling (LHS) numerical simulation method (Monte Carlo type method) was used. It has been found by the stochastic sensitivity analysis that the cyclic creep deformation variability is most sensitive to the Elastic modulus of concrete, compressive strength, mean stress, cyclic stress amplitude, number of cycle, in that order.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{MalonekFalcaoCruz, author = {Malonek, Helmuth Robert and Falc{\~a}o, M. Irene and Cruz, Carla}, title = {TOTALLY REGULAR VARIABLES AND APPELL SEQUENCES IN HYPERCOMPLEX FUNCTION THEORY}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2775}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27751}, pages = {5}, abstract = {The aim of our contribution is to clarify the relation between totally regular variables and Appell sequences of hypercomplex holomorphic polynomials (sometimes simply called monogenic power-like functions) in Hypercomplex Function Theory. After their introduction in 2006 by two of the authors of this note on the occasion of the 17th IKM, the latter have been subject of investigations by different authors with different methods and in various contexts. The former concept, introduced by R. Delanghe in 1970 and later also studied by K. G{\"u}rlebeck in 1982 for the case of quaternions, has some obvious relationship with the latter, since it describes a set of linear hypercomplex holomorphic functions all power of which are also hypercomplex holomorphic. Due to the non-commutative nature of the underlying Clifford algebra, being totally regular variables or Appell sequences are not trivial properties as it is for the integer powers of the complex variable z=x+ iy. Simple examples show also, that not every totally regular variable and its powers form an Appell sequence and vice versa. Under some very natural normalization condition the set of all para-vector valued totally regular variables which are also Appell sequences will completely be characterized. In some sense the result can also be considered as an answer to a remark of K. Habetha in chapter 16: Function theory in algebras of the collection Complex analysis. Methods, trends, and applications, Akademie-Verlag Berlin, (Eds. E. Lanckau and W. Tutschke) 225-237 (1983) on the use of exact copies of several complex variables for the power series representation of any hypercomplex holomorphic function.}, subject = {Angewandte Informatik}, language = {en} } @phdthesis{Ifesanya, author = {Ifesanya, Kunle}, title = {The Role of Government Agencies in Urban Housing Delivery in Lagos}, doi = {10.25643/bauhaus-universitaet.1761}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20121115-17619}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {386}, abstract = {There is a continuous exacerbation of environmental problems in big cities of today's world, thereby, diminishing the quality of life in them. Of particular concern is the fact that today's megacities are evolving in the developing world without corresponding growth in the economy, infrastructure and other human development indices. As urban population continues to grow in these cities of the Global South, governing institutions are usually unable to keep pace with their social responsibilities, thus, making the issue of urban governance very critical. This is because effective and efficient urban governance is highly essential for the creation, strengthening and sustenance of governing institutions. Lagos, a mega-city of over 15.45 million people and the most populous metropolitan area on the African continent epitomizes the fundamental grave characteristics of the emerging megacities of the Global South, thereby, constituting an apt choice in understanding the emerging megacities of the next generation. Two out of every three Lagos residents live in slums and de-humanizing physical and social conditions. Many of them sleep, work, eat and cook under highway bridges, at the mercy of weather elements. This research, therefore, evaluated urban governance through housing administration in Africa's largest megacity. It examines the extent of housing problems in the city, the causal factors and the culpability of government agencies statutorily responsible for the provision, control and management of housing development in Lagos - the tenth largest city in the world. A representative geographic part of the city which manifests classic characteristics of slum life, listed by Mike Davis as the largest slum in Africa and the 6th largest in the world - Ajegunle - was adopted for case study. The research design combined rigorous literature search (desk research) with quantitative and, especially, qualitative approaches to data collection. The qualitative approach was more intensely adopted because government officials often respond to enquiries with 'official answers and data' which may not be reliable and the study had to rely on keen observation of physical traces, social interaction and personal investigation. The cross-sectional research method was adopted. Information was solicited from house-owners, building industry professionals, sociologists and officials of relevant government agencies, through research tools like questionnaires, interviews, focused group discussions and personal observations. The analysis and discussion of these field data, in conjunction with the information from the desk research gave a better understanding of the status-quo, which informed the recommendations proposed in the dissertation for mitigating the problems. The research discovered that many of the statutory housing agencies have the capacity to effectively discharge their responsibilities. However, it was also shown that corruption and abdication of responsibilities by the staff of these agencies constitute primary causes of the chasm between the anticipated lofty outcome from the laudable building regulations/bye-laws and the appalling reality. It also discovered that lack of political will and apathy on the part of successive Governments of Lagos State to the improvement of housing conditions of the poor masses are major causes of the housing debacle in Lagos. Several germane and realistic recommendations for redressing the situation were subsequently proffered. These include amongst others, the conduction of an accurate census for Lagos, in conjunction with credible international agencies, as a requisite basis for effective planning of any sort. The process of obtaining legal titles for land should also be made less cumbersome, while the housing administration process should be computerized; in order to reduce inter-personal contacts between applicants and government officials to the barest minimum, as a means of curbing the wide spread corruption in the system.}, subject = {Housing}, language = {en} } @inproceedings{LegatiukBockGuerlebeck, author = {Legatiuk, Dmitrii and Bock, Sebastian and G{\"u}rlebeck, Klaus}, title = {THE PROBLEM OF COUPLING BETWEEN ANALYTICAL SOLUTION AND FINITE ELEMENT METHOD}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2773}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27730}, pages = {11}, abstract = {This paper is focused on the first numerical tests for coupling between analytical solution and finite element method on the example of one problem of fracture mechanics. The calculations were done according to ideas proposed in [1]. The analytical solutions are constructed by using an orthogonal basis of holomorphic and anti-holomorphic functions. For coupling with finite element method the special elements are constructed by using the trigonometric interpolation theorem.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{KulchytskyyHorokhovGubanovetal., author = {Kulchytskyy, Artem and Horokhov, Yevgen and Gubanov, Vadim and Golikov, Alexandr}, title = {THE INFLUENCE OF THE LOCAL CONCAVITY ON THE FUNCTIONING OF BEARING SHELL OF HIGH-RISE CONSTRUCTION}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2770}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27701}, pages = {10}, abstract = {Areas with various defects and damages, which reduce carrying capacity, were examined in a study of metal chimneys. In this work, the influence of the local dimples on the function of metal chimneys was considered. Modeling tasks were completed in the software packages LIRA and ANSYS. Parameters were identified, which characterize the local dimples, and a numerical study of the influence of local dimples on the stress-strain state of shells of metal chimneys was conducted. A distribution field of circular and meridional tension was analyzed in a researched area. Zones of influence of dimples on the bearing cover of metal chimneys were investigated. The bearing capacities of high-rise structures with various dimple geometries and various cover parameters were determined with respect to specified areas of the trunk. Dependent relationships are represented graphically for the decrease in bearing capacity of a cover with respect to dimples. Diameter and thickness of covers of metal chimneys were constructed according to the resulting data.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{Hitzer, author = {Hitzer, Eckhard}, title = {THE CLIFFORD FOURIER TRANSFORM IN REAL CLIFFORD ALGEBRAS}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2765}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27652}, pages = {11}, abstract = {We briefly review and use the recent comprehensive research on the manifolds of square roots of -1 in real Clifford geometric algebras Cl(p,q) in order to construct the Clifford Fourier transform. Basically in the kernel of the complex Fourier transform the complex imaginary unit j is replaced by a square root of -1 in Cl(p,q). The Clifford Fourier transform (CFT) thus obtained generalizes previously known and applied CFTs, which replaced the complex imaginary unit j only by blades (usually pseudoscalars) squaring to -1. A major advantage of real Clifford algebra CFTs is their completely real geometric interpretation. We study (left and right) linearity of the CFT for constant multivector coefficients in Cl(p,q), translation (x-shift) and modulation (w -shift) properties, and signal dilations. We show an inversion theorem. We establish the CFT of vector differentials, partial derivatives, vector derivatives and spatial moments of the signal. We also derive Plancherel and Parseval identities as well as a general convolution theorem.}, subject = {Angewandte Informatik}, language = {en} } @inproceedings{DeebZabel, author = {Deeb, Maher and Zabel, Volkmar}, title = {THE APPLICATION OF POD CURVES TO DAMAGE DETECTION BASED ON PARTIAL MODELS- A NUMERICAL AND EXPERIMENTAL STUDY}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2761}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170306-27615}, pages = {18}, abstract = {Non-destructive techniques for damage detection became the focus of engineering interests in the last few years. However, applying these techniques to large complex structures like civil engineering buildings still has some limitations since these types of structures are unique and the methodologies often need a large number of specimens for reliable results. For this reason, cost and time can greatly influence the final results. Model Assisted Probability Of Detection (MAPOD) has taken its place among the ranks of damage identification techniques, especially with advances in computer capacity and modeling tools. Nevertheless, the essential condition for a successful MAPOD is having a reliable model in advance. This condition is opening the door for model assessment and model quality problems. In this work, an approach is proposed that uses Partial Models (PM) to compute the Probability Of damage Detection (POD). A simply supported beam, that can be structurally modified and tested under laboratory conditions, is taken as an example. The study includes both experimental and numerical investigations, the application of vibration-based damage detection approaches and a comparison of the results obtained based on tests and simulations. Eventually, a proposal for a methodology to assess the reliability and the robustness of the models is given.}, subject = {Angewandte Informatik}, language = {en} } @phdthesis{Potthast, author = {Potthast, Martin}, title = {Technologies for Reusing Text from the Web}, doi = {10.25643/bauhaus-universitaet.1566}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20120217-15663}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {237}, abstract = {Texts from the web can be reused individually or in large quantities. The former is called text reuse and the latter language reuse. We first present a comprehensive overview of the different ways in which text and language is reused today, and how exactly information retrieval technologies can be applied in this respect. The remainder of the thesis then deals with specific retrieval tasks. In general, our contributions consist of models and algorithms, their evaluation, and for that purpose, large-scale corpus construction. The thesis divides into two parts. The first part introduces technologies for text reuse detection, and our contributions are as follows: (1) A unified view of projecting-based and embedding-based fingerprinting for near-duplicate detection and the first time evaluation of fingerprint algorithms on Wikipedia revision histories as a new, large-scale corpus of near-duplicates. (2) A new retrieval model for the quantification of cross-language text similarity, which gets by without parallel corpora. We have evaluated the model in comparison to other models on many different pairs of languages. (3) An evaluation framework for text reuse and particularly plagiarism detectors, which consists of tailored detection performance measures and a large-scale corpus of automatically generated and manually written plagiarism cases. The latter have been obtained via crowdsourcing. This framework has been successfully applied to evaluate many different state-of-the-art plagiarism detection approaches within three international evaluation competitions. The second part introduces technologies that solve three retrieval tasks based on language reuse, and our contributions are as follows: (4) A new model for the comparison of textual and non-textual web items across media, which exploits web comments as a source of information about the topic of an item. In this connection, we identify web comments as a largely neglected information source and introduce the rationale of comment retrieval. (5) Two new algorithms for query segmentation, which exploit web n-grams and Wikipedia as a means of discerning the user intent of a keyword query. Moreover, we crowdsource a new corpus for the evaluation of query segmentation which surpasses existing corpora by two orders of magnitude. (6) A new writing assistance tool called Netspeak, which is a search engine for commonly used language. Netspeak indexes the web in the form of web n-grams as a source of writing examples and implements a wildcard query processor on top of it.}, subject = {Information Retrieval}, language = {en} } @inproceedings{GhorashiRabczukRodenasGarciaetal., author = {Ghorashi, Seyed Shahram and Rabczuk, Timon and R{\´o}denas Garc{\´i}a, Juan Jos{\´e} and Lahmer, Tom}, title = {T-SPLINE BASED XIGA FOR ADAPTIVE MODELING OF CRACKED BODIES}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2763}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27637}, pages = {13}, abstract = {Safety operation of important civil structures such as bridges can be estimated by using fracture analysis. Since the analytical methods are not capable of solving many complicated engineering problems, numerical methods have been increasingly adopted. In this paper, a part of isotropic material which contains a crack is considered as a partial model and the proposed model quality is evaluated. EXtended IsoGeometric Analysis (XIGA) is a new developed numerical approach [1, 2] which benefits from advantages of its origins: eXtended Finite Element Method (XFEM) and IsoGeometric Analysis (IGA). It is capable of simulating crack propagation problems with no remeshing necessity and capturing singular field at the crack tip by using the crack tip enrichment functions. Also, exact representation of geometry is possible using only few elements. XIGA has also been successfully applied for fracture analysis of cracked orthotropic bodies [3] and for simulation of curved cracks [4]. XIGA applies NURBS functions for both geometry description and solution field approximation. The drawback of NURBS functions is that local refinement cannot be defined regarding that it is based on tensorproduct constructs unless multiple patches are used which has also some limitations. In this contribution, the XIGA is further developed to make the local refinement feasible by using Tspline basis functions. Adopting a recovery based error estimator in the proposed approach for evaluation of the model quality and performing the adaptive processes is in progress. Finally, some numerical examples with available analytical solutions are investigated by the developed scheme.}, subject = {Angewandte Informatik}, language = {en} } @masterthesis{Linda, type = {Bachelor Thesis}, author = {Linda, Luthardt}, title = {Systematik von Interaktionen zwischen mehreren Spielern in Social Network Spielen}, doi = {10.25643/bauhaus-universitaet.1661}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20120530-16610}, school = {Bauhaus-Universit{\"a}t Weimar}, pages = {92}, abstract = {Herausarbeitung sozialer Interaktionen in Social Games und deren m{\"o}gliche Anwendung um fachspezifische Lehrinhalte,z.B. aus dem Bereich der Bauphysik zu vermitteln.}, subject = {Gesellschaftsspiel}, language = {de} } @inproceedings{LiuLeimbachHartmann, author = {Liu, Xiangqin and Leimbach, Robert and Hartmann, Dietrich}, title = {SYSTEM IDENTIFICATION OF A WIND TURBINE STRUCTURE USING ROBUST MODEL UPDATING STRATEGY}, series = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, booktitle = {Digital Proceedings, International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering : July 04 - 06 2012, Bauhaus-University Weimar}, editor = {G{\"u}rlebeck, Klaus and Lahmer, Tom and Werner, Frank}, organization = {Bauhaus-Universit{\"a}t Weimar}, issn = {1611-4086}, doi = {10.25643/bauhaus-universitaet.2774}, url = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170314-27744}, pages = {11}, abstract = {This paper presents a robust model updating strategy for system identification of wind turbines. To control the updating parameters and to avoid ill-conditioning, the global sensitivity analysis using the elementary effects method is conducted. The formulation of the objective function is based on M¨uller-Slany's strategy for multi-criteria functions. As a simulationbased optimization, a simulation adapter is developed to interface the simulation software ANSYS and the locally developed optimization software MOPACK. Model updating is firstly tested on the beam model of the rotor blade. The defect between the numerical model and the reference has been markedly reduced by the process of model updating. The effect of model updating becomes more pronounced in the comparison of the measured and the numerical properties of the wind turbine model. The deviations of the frequencies of the updated model are rather small. The complete comparison including the free vibration modes by the modal assurance criteria shows the excellent coincidence of the modal parameters of the updated model with the ones from the measurements. By successful implementation of the model validation via model updating, the applicability and effectiveness of the solution concept has been demonstrated.}, subject = {Angewandte Informatik}, language = {en} }