@phdthesis{MartinezSoto,
  author    = {Martinez Soto, Aner},
  title     = {Analyse und Erweiterung von bestehenden Prognosemodellen zur Bestimmung des Endenergiebedarfs im Wohnungssektor},
  doi       = {10.25643/bauhaus-universitaet.3225},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170607-32251},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {291},
  abstract  = {Die wachsende Notwendigkeit zur Energieeinsparung hat in verschiedenen L{\"a}ndern zur Entwicklung von Prognosemodellen zur Bestimmung des Energiebedarfs im Wohnungssektor gef{\"u}hrt. Obwohl Prognosemodelle prinzipiell eine L{\"o}sung zur Bestimmung des Energiebedarfs und zur Beurteilung der Auswirkungen von zuk{\"u}nftigen Energieeinsparmaßnahmen darstellen, sind die bestehenden Modelle jedoch mit Unw{\"a}gbarkeiten in der Modellierung und M{\"a}ngeln bez{\"u}glich der verwendeten Daten und Methodik behaftet. In dieser Arbeit werden die {\"U}bertragbarkeit, Genauigkeit und stochastische Unsicherheit von zw{\"o}lf Prognosemodellen (MAED-2, FfE-Geb{\"a}udemodell, CDEM, REM, CREEM, ECCABS, REEPS, BREHOMES, LEAP, DECM, CHM, BSM) analysiert, wobei Deutschland als Fallbeispiel verwendet wird. Zur Verbesserung der {\"U}bertragbarkeit der bestehenden Modelle werden Anpassungen vorgeschlagen. Außerdem wird f{\"u}r jedes Modell eine Bestimmung der einflussreichsten Parameter auf den simulierten Endenergiebedarf mit Hilfe einer Sensitivit{\"a}tsanalyse vorgenommen. Es konnte gezeigt werden, dass Modelle mit einem hohen Detaillierungsgrad nicht zwangsl{\"a}ufig genauere Ergebnisse f{\"u}r den Endenergiebedarf garantieren. Dennoch wurde festgestellt, dass Modelle mit einem niedrigen Detaillierungsgrad Ergebnisse mit gr{\"o}ßeren Unsicherheiten liefern als Modelle mit einem h{\"o}heren Detaillierungsgrad. Es wurde weiterhin festgestellt, dass die einflussreichsten Parameter zur Bestimmung des Endenergiebedarfs im Wohnungssektor Innenraumtemperatur, Außentemperatur (Gradtagzahl), Bev{\"o}lkerungsentwicklung und Anzahl der Geb{\"a}ude/Wohnungen sind. Auf der Grundlage der Erkenntnisse zur Bewertung bestehender Modelle und der Bestimmung der einflussreichsten Parameter wurde ein optimiertes Prognosemodell (Transferable Residential Energy Model, TREM) entwickelt. Mit dessen Hilfe wurde die Entwicklung des Endenergiebedarfs im deutschen Wohnungssektor sowie in anderen L{\"a}ndern (Vereinigtes K{\"o}nigsreich und Chile) prognostiziert. Diese Ergebnisse wurden anschließend mit statistischen Daten verglichen. Das TREM-Modell bestimmt den Endenergiebedarf auf der Grundlage der wahrscheinlichsten Variationen der einflussreichsten Eingangsparameter mit Hilfe einer Monte-Carlo-Simulation. Im Gegensatz zu bestehenden Modellierungsans{\"a}tzen liefert das Modell damit auch einen Bereich mit Wahrscheinlichkeitsb{\"a}ndern f{\"u}r den zuk{\"u}nftigen Endenergiebedarf. Die Ergebnisse des TREM-Modells zeigen, dass das Modell genauere Ergebnisse liefern kann als derzeitige Modelle mit einem Mittelwert der prozentualen Differenz niedriger als 5\% und einem Korrelationskoeffizienten r h{\"o}her als 0,35 und dar{\"u}ber hinaus dazu geeignet ist, ohne Anpassungen eine Prognose der Entwicklung des zuk{\"u}nftigen Endenergiebedarfs im Wohnungssektor f{\"u}r unterschiedliche L{\"a}nder zu erstellen.},
  subject      = {Energieverbrauch},
  language  = {de}
}
@phdthesis{MeyerKohlstock,
  author    = {Meyer-Kohlstock, Daniel},
  title     = {Prospects for Biochar in a Bio-Waste Cascade},
  doi       = {10.25643/bauhaus-universitaet.3631},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20171108-36310},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {118},
  abstract  = {In the early 2000s the pre-Columbian, anthropologically produced black soil in the Amazon basin, „Terra Preta de {\´I}ndio", received greater scientific attention. Compared to the surrounding poor soils, this very fertile anthrosol contains significantly higher levels of microorganisms and nutrients. The reason for this was determined to be the likewise high levels of charred biomass. This stable carbon, now called biochar, has since been intensively examined as an option to improve soil and to store carbon. Although the creation of Terra Preta was most likely based on a purposeful utilization of organic residues from households and gardens, biochar plays no role in the current recycling of bio-waste. However, the implementation of biochar could lead to many improvements. Results from agricultural research suggest that not only the yield capacity of soils can be increased but also the process performance of composting and biogas plants. The latter is especially relevant since currently about 40\% of all collected bio-waste in Germany is recycled in an energy-material cascade consisting of anaerobic digestion and composting. The use of biochar in this cascade could then sequentially increase biogas yields, reduce greenhouse gas emissions, and improve compost quality. To realize the aforementioned advantages, the concept of biochar has to be integrated into the existing bio-waste cascade as practically as possible. This was done by the development of a theoretical scenario that allowed the analysis of energy and material flows to evaluate biochar's recycling performance. Furthermore, the legal and economic framework were examined to assess the feasibility of the extended cascade and to suggest possible adjustments to the frameworks.},
  subject      = {Kompost},
  language  = {en}
}
@phdthesis{Msekh,
  author    = {Msekh, Mohammed Abdulrazzak},
  title     = {Phase Field Modeling for Fracture with Applications to Homogeneous and Heterogeneous Materials},
  doi       = {10.25643/bauhaus-universitaet.3229},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170615-32291},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {190},
  abstract  = {The thesis presents an implementation including different applications of a variational-based approach for gradient type standard dissipative solids. Phase field model for brittle fracture is an application of the variational-based framework for gradient type solids. This model allows the prediction of different crack topologies and states. Of significant concern is the application of theoretical and numerical formulation of the phase field modeling into the commercial finite element software Abaqus in 2D and 3D. The fully coupled incremental variational formulation of phase field method is implemented by using the UEL and UMAT subroutines of Abaqus. The phase field method considerably reduces the implementation complexity of fracture problems as it removes the need for numerical tracking of discontinuities in the displacement field that are characteristic of discrete crack methods. This is accomplished by replacing the sharp discontinuities with a scalar damage phase field representing the diffuse crack topology wherein the amount of diffusion is controlled by a regularization parameter. The nonlinear coupled system consisting of the linear momentum equation and a diffusion type equation governing the phase field evolution is solved simultaneously via a Newton- Raphson approach. Post-processing of simulation results to be used as visualization module is performed via an additional UMAT subroutine implemented in the standard Abaqus viewer. In the same context, we propose a simple yet effective algorithm to initiate and propagate cracks in 2D geometries which is independent of both particular constitutive laws and specific element technology and dimension. It consists of a localization limiter in the form of the screened Poisson equation with, optionally, local mesh refinement. A staggered scheme for standard equilibrium and screened Cauchy equations is used. The remeshing part of the algorithm consists of a sequence of mesh subdivision and element erosion steps. Element subdivision is based on edge split operations using a given constitutive quantity (either damage or void fraction). Mesh smoothing makes use of edge contraction as function of a given constitutive quantity such as the principal stress or void fraction. To assess the robustness and accuracy of this algorithm, we use both quasi-brittle benchmarks and ductile tests. Furthermore, we introduce a computational approach regarding mechanical loading in microscale on an inelastically deforming composite material. The nanocomposites material of fully exfoliated clay/epoxy is shaped to predict macroscopic elastic and fracture related material parameters based on their fine-scale features. Two different configurations of polymer nanocomposites material (PNCs) have been studied. These configurations are fully bonded PNCs and PNCs with an interphase zone formation between the matrix and the clay reinforcement. The representative volume element of PNCs specimens with different clay weight contents, different aspect ratios, and different interphase zone thicknesses are generated by adopting Python scripting. Different constitutive models are employed for the matrix, the clay platelets, and the interphase zones. The brittle fracture behavior of the epoxy matrix and the interphase zones material are modeled using the phase field approach, whereas the stiff silicate clay platelets of the composite are designated as a linear elastic material. The comprehensive study investigates the elastic and fracture behavior of PNCs composites, in addition to predict Young's modulus, tensile strength, fracture toughness, surface energy dissipation, and cracks surface area in the composite for different material parameters, geometry, and interphase zones properties and thicknesses.},
  subject      = {Finite-Elemente-Methode},
  language  = {en}
}
@phdthesis{Nariman,
  author    = {Nariman, Nazim},
  title     = {Numerical Methods for the Multi-Physical Analysis of Long Span Cable-Stayed Bridges},
  doi       = {10.25643/bauhaus-universitaet.3710},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20171122-37105},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {236},
  abstract  = {The main categories of wind effects on long span bridge decks are buffeting, flutter, vortex-induced vibrations (VIV) which are often critical for the safety and serviceability of the structure. With the rapid increase of bridge spans, research on controlling wind-induced vibrations of long span bridges has been a problem of great concern.The developments of vibration control theories have led to the wide use of tuned mass dampers (TMDs) which has been proven to be effective for suppressing these vibrations both analytically and experimentally. Fire incidents are also of special interest in the stability and safety of long span bridges due to significant role of the complex phenomenon through triple interaction between the deck with the incoming wind flow and the thermal boundary of the surrounding air. This work begins with analyzing the buffeting response and flutter instability of three dimensional computational structural dynamics (CSD) models of a cable stayed bridge due to strong wind excitations using ABAQUS finite element commercial software. Optimization and global sensitivity analysis are utilized to target the vertical and torsional vibrations of the segmental deck through considering three aerodynamic parameters (wind attack angle, deck streamlined length and viscous damping of the stay cables). The numerical simulations results in conjunction with the frequency analysis results emphasized the existence of these vibrations and further theoretical studies are possible with a high level of accuracy. Model validation is performed by comparing the results of lift and moment coefficients between the created CSD models and two benchmarks from the literature (flat plate theory) and flat plate by (Xavier and co-authors) which resulted in very good agreements between them. Optimum values of the parameters have been identified. Global sensitivity analysis based on Monte Carlo sampling method was utilized to formulate the surrogate models and calculate the sensitivity indices. The rational effect and the role of each parameter on the aerodynamic stability of the structure were calculated and efficient insight has been constructed for the stability of the long span bridge. 2D computational fluid dynamics (CFD) models of the decks are created with the support of MATLAB codes to simulate and analyze the vortex shedding and VIV of the deck. Three aerodynamic parameters (wind speed, deck streamlined length and dynamic viscosity of the air) are dedicated to study their effects on the kinetic energy of the system and the vortices shapes and patterns. Two benchmarks from the literature (Von Karman) and (Dyrbye and Hansen) are used to validate the numerical simulations of the vortex shedding for the CFD models. A good consent between the results was detected. Latin hypercube experimental method is dedicated to generate the surrogate models for the kinetic energy of the system and the generated lift forces. Variance based sensitivity analysis is utilized to calculate the main sensitivity indices and the interaction orders for each parameter. The kinetic energy approach performed very well in revealing the rational effect and the role of each parameter in the generation of vortex shedding and predicting the early VIV and the critical wind speed. Both one-way fluid-structure interaction (one-way FSI) simulations and two-way fluid-structure interaction (two-way FSI) co-simulations for the 2D models of the deck are executed to calculate the shedding frequencies for the associated wind speeds in the lock-in region in addition to the lift and drag coefficients. Validation is executed with the results of (Simiu and Scanlan) and the results of flat plate theory compiled by (Munson and co-authors) respectively. High levels of agreements between all the results were detected. A decrease in the critical wind speed and the shedding frequencies considering (two-way FSI) was identified compared to those obtained in the (one-way FSI). The results from the (two-way FSI) approach predicted appreciable decrease in the lift and drag forces as well as prediction of earlier VIV for lower critical wind speeds and lock-in regions which exist at lower natural frequencies of the system. These conclusions help the designers to efficiently plan and consider for the design and safety of the long span bridge before and after construction. Multiple tuned mass dampers (MTMDs) system has been applied in the three dimensional CSD models of the cable stayed bridge to analyze their control efficiency in suppressing both wind -induced vertical and torsional vibrations of the deck by optimizing three design parameters (mass ratio, frequency ratio and damping ratio) for the (TMDs) supporting on actual field data and minimax optimization technique in addition to MATLAB codes and Fast Fourier Transform technique. The optimum values of each parameter were identified and validated with two benchmarks from the literature, first with (Wang and co-authors) and then with (Lin and co-authors). The validation procedure detected a good agreement between the results. Box-Behnken experimental method is dedicated to formulate the surrogate models to represent the control efficiency of the vertical and torsional vibrations. Sobol's sensitivity indices are calculated for the design parameters in addition to their interaction orders. The optimization results revealed better performance of the MTMDs in controlling both the vertical and the torsional vibrations for higher mode shapes. Furthermore, the calculated rational effect of each design parameter facilitates to increase the control efficiency of the MTMDs in conjunction with the support of the surrogate models which simplifies the process of analysis for vibration control to a great extent. A novel structural modification approach has been adopted to eliminate the early coupling between the bending and torsional mode shapes of the cable stayed bridge. Two lateral steel beams are added to the middle span of the structure. Frequency analysis is dedicated to obtain the natural frequencies of the first eight mode shapes of vibrations before and after the structural modification. Numerical simulations of wind excitations are conducted for the 3D model of the cable stayed bridge. Both vertical and torsional displacements are calculated at the mid span of the deck to analyze the bending and the torsional stiffness of the system before and after the structural modification. The results of the frequency analysis after applying lateral steel beams declared that the coupling between the vertical and torsional mode shapes of vibrations has been removed to larger natural frequencies magnitudes and higher rare critical wind speeds with a high factor of safety. Finally, thermal fluid-structure interaction (TFSI) and coupled thermal-stress analysis are utilized to identify the effects of transient and steady state heat-transfer on the VIV and fatigue of the deck due to fire incidents. Numerical simulations of TFSI models of the deck are dedicated to calculate the lift and drag forces in addition to determining the lock-in regions once using FSI models and another using TFSI models. Vorticity and thermal fields of three fire scenarios are simulated and analyzed. The benchmark of (Simiu and Scanlan) is used to validate the TFSI models, where a good agreement was manifested between the two results. Extended finite element method (XFEM) is adopted to create 3D models of the cable stayed bridge to simulate the fatigue of the deck considering three fire scenarios. The benchmark of (Choi and Shin) is used to validate the damaged models of the deck in which a good coincide was seen between them. The results revealed that the TFSI models and the coupled thermal-stress models are significant in detecting earlier vortex induced vibration and lock-in regions in addition to predicting damages and fatigue of the deck and identifying the role of wind-induced vibrations in speeding up the damage generation and the collapse of the structure in critical situations.},
  subject      = {Stabilit{\"a}t},
  language  = {en}
}
@phdthesis{Oroz,
  author    = {Oroz, Gonzalo},
  title     = {Die Wege der Ungleichheit. Eine Studie {\"u}ber die Beziehung zwischen sozial-r{\"a}umlicher Segregation und Verkehrsinfrastruktur. Der Fall Santiago de Chile},
  doi       = {10.25643/bauhaus-universitaet.2924},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170412-29244},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {353},
  abstract  = {Die Arbeit besch{\"a}ftigt sich mit den Auswirkungen des Baus von neuen Stadtautobahnen in Santiago de Chile. Ziel der Studie ist, die Ver{\"a}nderungen im Segregationsmuster der Hauptstadt Chiles, die durch den Bau dieser Autobahnen entstanden sind, zu beschreiben. Die Arbeit betrachtet die Entstehung von Segregationsmustern als kulturell-historisches Ph{\"a}nomen urbaner Bedeutung, weswegen die Entwicklung der Stadt Santiago und deren Segregationsmuster nicht nur aus der Perspektive der Stadtsoziologie und der Stadtgeographie, sondern auch aus einer historischen Perspektive analysiert wird. Dabei liegt der Schwerpunkt der Arbeit auf der Wechselbeziehung zwischen Verkehrsinfrastruktur und sozial-r{\"a}umlicher Verteilung der verschiedenen sozialen Gruppen. Die Entstehung der neuen Stadtautobahnen in Santiago de Chile l{\"a}sst sich nur durch eine mehrdimensionale Betrachtung erkl{\"a}ren. Diese Bauten und die besondere Art in der sie gebaut und betrieben werden, konnten nur durch die Einf{\"u}hrung von Konzessionsmechanismen innerhalb einer neoliberalen Markwirtschaft entstehen. In diesem sozial-{\"o}konomischer Rahmen, bei dem die B{\"u}rger lediglich als potenzielle Kunden betrachtet werden, sind die Infrastrukturbauten - darunter auch die Stadtautobahnen - maßgeschneiderte Produkte f{\"u}r eine Minderheit. Dieses Konzept hat gravierende Folgen f{\"u}r das Sozialgef{\"u}ge der Stadt Santiago. Die Folgen der Einf{\"u}hrung der Stadtautobahnen auf das Segregationsmuster und das Sozialgef{\"u}ge der Hauptstadt Chiles werden anhand zweier Fallstudien veranschaulicht. Mittels einer mehrschichtigen qualitativen Methodik werden die Auswirkungen des Baus von Stadtautobahnen im Armenviertel »Santo Tom{\´a}s« des s{\"u}dlichen Stadtbezirk »La Pintana« und im elit{\"a}ren »Condominio La Reserva« im n{\"o}rdlichen Ausdehnungsgebiet »Chacabuco« analysiert. Anschließend wird ein neues Beschreibungsmodell f{\"u}r die lateinamerikanische Stadt vorgeschlagen; das »symbiotische Stadtmodell« st{\"u}tzt sich zum gr{\"o}ßten Teil auf den Ausbau des Autobahnnetzes.},
  subject      = {Segregation},
  language  = {de}
}
@phdthesis{Peters,
  author    = {Peters, Simone},
  title     = {The Influence of Power Ultrasound on Setting and Strength Development of Cement Suspensions},
  isbn      = {ISBN 978-3-00-055602-9},
  doi       = {10.25643/bauhaus-universitaet.2744},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170210-27446},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {146},
  abstract  = {Ein aktuelles Thema in der Forschung der Betonindustrie ist die gezielte Steuerung des Erstarrens und der Entwicklung der (Fr{\"u}h)Festigkeit von Betonen und M{\"o}rteln. Aus {\"o}konomischer Sicht sind außerdem die Reduktion der CO2-Emission und die Schonung von Ressourcen und Energie wichtige Forschungsschwerpunkte. Eine M{\"o}glichkeit zum Erreichen dieser Ziele ist es, die Reaktivit{\"a}t/Hydratation der silikatischen Klinkerphasen gezielt anzuregen. Neben den bereits bekannten M{\"o}glichkeiten der Hydratationsbeschleunigung (u.a. W{\"a}rmebehandlung, Zugabe von Salzen) bietet die Anwendung von Power-Ultraschall (PUS) eine weitere Alternative zur Beschleunigung der Zementhydratation. Da bis zum jetzigen Zeitpunkt noch keine Erfahrungen zum Einsatz von PUS in der Zementchemie vorliegen, sollen mit der vorliegenden Arbeit grundlegende Kenntnisse zum Einfluss von PUS auf das Fließ- und Erstarrungsverhalten von Zementsuspensionen erarbeitet werden. Dazu wurde die Arbeit in f{\"u}nf Hauptuntersuchungsabschnitte aufgeteilt. Im ersten Teil wurden optimale PUS-Parameter wie Amplitude und Energieeintrag ermittelt, die eine effiziente Beschleunigung der Portlandzement(CEM I)hydratation bei kurzen Beschallzeiten und begrenzter Zementleimtemperaturerh{\"o}hung erlauben. Mit Hilfe unabh{\"a}ngiger Untersuchungsmethoden (Bestimmung des Erstarrungsbeginns, der Festigkeitsentwicklung, zerst{\"o}rungsfreier Ultraschallpr{\"u}fung, isothermer W{\"a}rmeflusskalorimetrie, hochaufl{\"o}sender Rasterelektronmikroskopie (REM) wurde die Wirkung von PUS auf den Hydratationsverlauf von CEM I-Suspensionen charakterisiert. Die Ergebnisse zeigen, dass die Behandlung von CEM I-Suspensionen mit PUS grunds{\"a}tzlich ein beschleunigtes Erstarren und eine beschleunigte (Fr{\"u}h)Festigkeitsentwicklung hervorruft. Anhand von REM-Untersuchungen konnte eindeutig nachgewiesen werden, dass die Beschleunigung der CEM I-Hydratation mit einer beschleunigten Hydratation der Hauptklinkerphase Alit korreliert. Auf Grundlage dieser Erkenntnisse wurden die Ursachen der Aktivierung der Alithydratation untersucht. Dazu wurden Untersuchungen an Einzelsystemen des CEM I (silikatische Klinkerphase) durchgef{\"u}hrt. Es ist bekannt, das die Hydratation der Hauptklinkerphase Alit (in der reinen Form Tricalciumsilikat 3CaO*SiO2; C3S) durch L{\"o}sungs-/F{\"a}llungsreaktionen (Bildung von Calcium-Silikat-Hydrat Phasen, C-S-H Phasen) bestimmt wird. Mit Hilfe von Untersuchungen zur Aufl{\"o}sung (C3S) und Kristallbildung (C-S-H Phasen) in L{\"o}sungen und Suspensionen (Aufzeichnung der elektrischen Leitf{\"a}higkeit sowie Bestimmung der Ionenkonzentrationen der w{\"a}ssrigen Phase, REM-Charakterisierung der Pr{\"a}zipitate) wurde die Beeinflussung dieser durch eine PUS-Behandlung charakterisiert. Die Ergebnisse zeigen, dass in partikelfreien L{\"o}sungen (prim{\"a}re Keimbildung) eine PUS-Behandlung keinen Einfluss auf die Kinetik der Kristallisation von C-S-H Phasen hervorruft. Das heißt, auch die durch PUS eingetragene Energie reicht offensichtlich nicht aus, um in Abwesenheit von Oberfl{\"a}chen die C-S-H Phasen Bildung zu beschleunigen. Das weist darauf hin, dass die Bildung von C-S-H Phasen nicht durch eine Beschleunigung von Ionen in der L{\"o}sung (erh{\"o}hte Diffusion durch Anwendung von PUS) hervorgerufen wird. Eine Beschleunigung des Kristallisationsprozesses (Keimbildung und Wachstum von C-S-H Phasen) durch PUS wird nur in Anwesenheit von Partikeln in der L{\"o}sung (Suspension) erzielt. Das belegen Ergebnisse, bei denen die Bildung erster C-S-H Phasen bei geringer {\"U}bers{\"a}ttigung (heterogene Keimbildung, in Anwesenheit von Oberfl{\"a}chen) erfolgt. Unter diesen Bedingungen konnte gezeigt werden, dass PUS innerhalb der ersten 30 Minuten der Hydratation eine erh{\"o}hte F{\"a}llung von ersten C-S-H Phasen bewirkt. Diese fungieren dann vermutlich w{\"a}hrend der Haupthydratation als Keim bzw. geeignete Oberfl{\"a}che zum beschleunigten Aufwachsen von weiteren C-S-H Phasen. Weiterhin ist vorstellbar, dass (in Analogie zu anderen Bereichen der Sonochemie) PUS durch Kavitation Schockwellen hervorruft, welche Partikel und w{\"a}ssriges Medium beschleunigen und damit erh{\"o}hte Partikelbewegungen und -kollisionen induziert. Dies wiederum bewirkt, dass die anf{\"a}nglich auf der C3S-Oberfl{\"a}che gebildeten C-S-H Phasen teilweise wieder entfernt werden. Damit ist das Inl{\"o}sunggehen von Ca- und Si-Ionen aus dem C3S weiterhin m{\"o}glich. Um den genauen Mechanismus weiter zu charakterisieren sollten mit geeigneten Methoden weitere Untersuchungen durchgef{\"u}hrt werden. Im zweiten Teil der Arbeit wurde der Einfluss von PUS auf das Fließverhalten von CEM I-Suspensionen untersucht. Aus der Anwendung von PUS in anderen technischen Bereichen sind unter anderem Effekte wie das Entl{\"u}ften, das Homogenisieren und das Dispergieren von Suspensionen und Emulsionen mittels PUS bekannt. Mit Hilfe der Bestimmung des Luftporengehaltes, Sedimentationsversuchen und cryo-SEM Untersuchungen wurde der Einfluss von PUS auf CEM I-Suspensionen charakterisiert. Die Ergebnisse belegen, dass durch PUS eine verbesserte Homogenit{\"a}t und Dispergierung der CEM I-Suspension erzielt wird. Damit wird f{\"u}r CEM I-Suspensionen unterschiedlichster w/z-Werte eine verbesserte Fließf{\"a}higkeit festgestellt. Ergebnisse der Bestimmung von Ausbreitmaßen und Trichterauslaufzeiten zeigen, dass PUS einen direkten Einfluss vor allem auf die Viskosit{\"a}t der CEM I-Suspensionen besitzt. Werden Fließmitteln (FM) der CEM I-Suspension zugegeben, wird nicht in jedem Fall eine verbesserte Fließf{\"a}higkeit festgestellt. Hier scheint unter bestimmten Voraussetzungen (w/z-Wert, FM-Gehalt, PUS) die Reaktion zwischen Aluminat- und Sulfatphase des Klinkers gest{\"o}rt. Zur eindeutigen Kl{\"a}rung dieses Sachverhaltes bedarf es jedoch weiterer quantitativer Untersuchungen zum Reaktionsumsatz. Im dritten Teil der Arbeit wurden die am CEM I gewonnenen Erkenntnisse zum Einfluss von PUS auf die Hydratation an Portland-H{\"u}ttensand(H{\"U}S)-Zement-Systemen verifiziert. Daf{\"u}r wurden auch in diesem Teil der Arbeit zun{\"a}chst die optimalen PUS-Parameter festgelegt und der Einfluss auf das Erstarrung- und Erh{\"a}rtungsverhalten dokumentiert. Untersuchungsmethoden sind unter anderem die Bestimmung des Erstarrungsbeginns und der (Fr{\"u}h)Festigkeitsentwicklung, Temperaturaufzeichnungen und isothermale W{\"a}rmeflusskalorimetrie sowie REM. Die Ergebnisse zeigen, dass auch die Reaktion von H{\"U}S-Zementen durch PUS beschleunigt wird. Weiterf{\"u}hrende Untersuchungen belegen, dass die erzielte Beschleunigung vorwiegend auf der Beschleunigung der Alitkomponente des CEM I beruht. Im Fokus der Teile vier und f{\"u}nf dieser Arbeit stand die Anwendbarkeit der PUS-Technik unter praktischen Bedingungen. Zum einen wurde die Anwendbarkeit von PUS in fertig gemischten M{\"o}rteln beurteilt. Anhand des Vergleichs wichtiger Frisch- und Festm{\"o}rteleigenschaften unterschiedlich hergestellter M{\"o}rtel (beschallt im Anschluss an konventionelle Mischtechnik, beschallt im Anschluss an Suspensionsmischtechnik mit anschließender Zumischung der Gesteinsk{\"o}rnung und nicht beschallt) wird gezeigt, dass im Fall von M{\"o}rteln mit hohem Leimanteil eine durch PUS induzierte beschleunigte Festigkeitsentwicklung auch mit herk{\"o}mmlichen Mischabl{\"a}ufen (ohne aufwendige Umstellung des Mischprozesses) m{\"o}glich ist. Abschließend wird untersucht, ob der Herstellungsprozess von Wandbauteilen im Fertigteilwerk durch den Einsatz von PUS optimiert werden kann und ob eine Einbindung der PUS-Technik in den Fertigungsprozess ohne gr{\"o}ßeren Aufwand m{\"o}glich ist. Dazu wurden in einem ersten Schritt die Frisch- und Festbetoneigenschaften eines aktuell angewendeten selbstverdichtenden Betons im Labormaßstab (M{\"o}rtel) in Abh{\"a}ngigkeit einer PUS-Behandlung dokumentiert und mit der seiner unbeschallten Referenz verglichen. Aufgrund der durch PUS verursachten verbesserten Fließ- und Festigkeitseigenschaften kann die beschallte M{\"o}rtelrezeptur hinsichtlich Fließmittelgehalt und Dauer der W{\"a}rmebehandlung optimiert werden. Somit werden ca. 30 \% der Fließmittelzugabe und 40 \% der Dauer der W{\"a}rmebehandlung eigespart. Eine Einbindung der PUS-Technik in das betrachtete Fertigteilwerk ist nach {\"U}berpr{\"u}fung der konstruktiven Gegebenheiten der Fertigungsstrukturen ohne gr{\"o}ßeren Aufwand m{\"o}glich.},
  subject      = {Cement},
  language  = {en}
}
@phdthesis{Podlaszewska,
  author    = {Podlaszewska, Rizky Suci Ammalia},
  title     = {The Placemaking of Destination. Localization and Commoditization process of Urban Tourism. Study case Palembang Indonesia},
  doi       = {10.25643/bauhaus-universitaet.3699},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20171201-36995},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {This research addresses the discourse of tourism as a tool for place-making of urban destination. Relevant to the study of place-making is the analysis of the commoditization and localization process dependent upon the appropriation of urban landscape and local cultures. In the research, localization is interpreted as the act of determining the attributes of locality, while commoditization is defined as the process by which local attributes that have commercial potential end up in becoming tourism commodity. Following this, the commoditization of intrinsic cultural value is disseminated within a branding strategy and intervention reflecting social and political relations. Therefore, the research suggests that tourism place-making has not only been constructed through the top-down regulatory body, but has been also generated through the attributes of its locality. By utilizing the critical and constructivist paradigm, the research depicts the conditions of the localization and commoditization process in establishing the base line of its realization within the symbolic economy. Thus, a qualitative case study approach was adopted. The study area of this dissertation is Palembang, as one of the capital cities in Indonesia advancing in its overall urban development. To investigate urban tourism as a tool for development strategy, it is useful to investigate the role of tourism which embodies (1) spatial transformation; how tourism gives significant impacts on urban form, and (2) the socio-cultural aspect; how neighbourhood is related to tourism industry. The findings suggest that tourism place-making involves the reciprocity of urban dynamics: cities take on tourism as a reference model of development, and tourist areas adopt the proliferation of cultural lifestyle to meet the industry's demands.},
  subject      = {Urbanistik},
  language  = {en}
}
@phdthesis{Romallosa,
  author    = {Romallosa, Aries Roda D.},
  title     = {Briquette Production By The Informal Sector: The Case of UCLA in Iloilo City, Philippines},
  doi       = {10.25643/bauhaus-universitaet.3233},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170620-32335},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {156},
  abstract  = {The construction and operation of a sanitary landfill (SLF) in the Philippines presents concerns on the regulation of the activities of the informal sector in the area. In anticipation of these directives, an association of informal waste reclaimers group called Uswag Calajunan Livelihood Association, Inc. (UCLA) was formed in May 2009. One option identified was the waste-to-energy activity through the production of fuel briquettes. With the availability of raw materials in the area, what was lacking then was an appropriate technology that would cater to their needs. This study, therefore, presented the case of UCLA on how socio-economic and technical aspects was integrated for the development and improvement of a briquetting technology needed in the production of quality briquettes as part of their income generating activities. A non-experimental posttest only design was utilized for the collection of descriptive information. Descriptions and discussions were also made on the enhancement of the briquetting machine from the first hand-press molder developed until the finalized design was attained. Results revealed that the improved briquetting technology withstood the wear and tear of operation showing a significant (P<0.01) increase on the production rate (220 pcs/hr; 4 kg/hr) and bulk density (444.83 kg/m3) of briquettes produced. The quality of cylindrical briquettes produced in terms of bulk density, heating value (15.13 MJ/kg), moisture (6.2\%), N and S closely met or has met the requirements of DIN 51731. Based on the operating expenses, the briquettes may be marked-up to Php0.25/pc (USD0.006) or Php15.00/kg (USD0.34) for profit generation. The potential daily earnings of Php130.00 (USD2.95) to Php288.56 (USD6.56) generated in producing briquettes are higher when compared to the majority of waste reclaimers' daily income of Php124.00 (USD2.82). The high positive response (93\%) on the usability of briquettes and the willingness of the respondents (81\%) to buy them when sold in the market indicates its promising potential as fuel in the nearby communities. Results of briquette production citing the case of UCLA could be considered as potential source of income given the social, technical, economic and environmental feasibility of the experiment. This method of utilizing wastes in an urban setting of a developing country with similar socio-economic and physical set-ups may also be recommended for testing or replication.},
  subject      = {Biotechnologie},
  language  = {en}
}
@phdthesis{Schwedler,
  author    = {Schwedler, Michael},
  title     = {Integrated structural analysis using isogeometric finite element methods},
  doi       = {10.25643/bauhaus-universitaet.2737},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170130-27372},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  pages     = {209},
  abstract  = {The gradual digitization in the architecture, engineering, and construction industry over the past fifty years led to an extremely heterogeneous software environment, which today is embodied by the multitude of different digital tools and proprietary data formats used by the many specialists contributing to the design process in a construction project. Though these projects become increasingly complex, the demands on financial efficiency and the completion within a tight schedule grow at the same time. The digital collaboration of project partners has been identified as one key issue in successfully dealing with these challenges. Yet currently, the numerous software applications and their respective individual views on the design process severely impede that collaboration. An approach to establish a unified basis for the digital collaboration, regardless of the existing software heterogeneity, is a comprehensive digital building model contributed to by all projects partners. This type of data management known as building information modeling (BIM) has many benefits, yet its adoption is associated with many difficulties and thus, proceeds only slowly. One aspect in the field of conflicting requirements on such a digital model is the cooperation of architects and structural engineers. Traditionally, these two disciplines use different abstractions of reality for their models that in consequence lead to incompatible digital representations thereof. The onset of isogeometric analysis (IGA) promised to ease the discrepancy in design and analysis model representations. Yet, that initial focus quickly shifted towards using these methods as a more powerful basis for numerical simulations. Furthermore, the isogeometric representation alone is not capable of solving the model abstraction problem. It is thus the intention of this work to contribute to an improved digital collaboration of architects and engineers by exploring an integrated analysis approach on the basis of an unified digital model and solid geometry expressed by splines. In the course of this work, an analysis framework is developed that utilizes such models to automatically conduct numerical simulations commonly required in construction projects. In essence, this allows to retrieve structural analysis results from BIM models in a fast and simple manner, thereby facilitating rapid design iterations and profound design feedback. The BIM implementation Industry Foundation Classes (IFC) is reviewed with regard to its capabilities of representing the unified model. The current IFC schema strongly supports the use of redundant model data, a major pitfall in digital collaboration. Additionally, it does not allow to describe the geometry by volumetric splines. As the pursued approach builds upon a unique model for both, architectural and structural design, and furthermore requires solid geometry, necessary schema modifications are suggested. Structural entities are modeled by volumetric NURBS patches, each of which constitutes an individual subdomain that, with regard to the analysis, is incompatible with the remaining full model. The resulting consequences for numerical simulation are elaborated in this work. The individual subdomains have to be weakly coupled, for which the mortar method is used. Different approaches to discretize the interface traction fields are implemented and their respective impact on the analysis results is evaluated. All necessary coupling conditions are automatically derived from the related geometry model. The weak coupling procedure leads to a linear system of equations in saddle point form, which, owed to the volumetric modeling, is large in size and, the associated coefficient matrix has, due to the use of higher degree basis functions, a high bandwidth. The peculiarities of the system require adapted solution methods that generally cause higher numerical costs than the standard procedures for symmetric, positive-definite systems do. Different methods to solve the specific system are investigated and an efficient parallel algorithm is finally proposed. When the structural analysis model is derived from the unified model in the BIM data, it does in general initially not meet the requirements on the discretization that are necessary to obtain sufficiently accurate analysis results. The consequently necessary patch refinements must be controlled automatically to allowfor an entirely automatic analysis procedure. For that purpose, an empirical refinement scheme based on the geometrical and possibly mechanical properties of the specific entities is proposed. The level of refinement may be selectively manipulated by the structural engineer in charge. Furthermore, a Zienkiewicz-Zhu type error estimator is adapted for the use with isogeometric analysis results. It is shown that also this estimator can be used to steer an adaptive refinement procedure.},
  subject      = {Finite-Elemente-Methode},
  language  = {en}
}
@phdthesis{Smirnova,
  author    = {Smirnova, Elena},
  title     = {"Kennst du das Land, wo bl{\"u}ht Oranienbaum?" - A Case Study on Strategic and Territorial Planning in St. Petersburg (Russia)},
  doi       = {10.25643/bauhaus-universitaet.3255},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:wim2-20170711-32556},
  school      = {Bauhaus-Universit{\"a}t Weimar},
  abstract  = {The research examines the system of strategic and territorial planning of St. Petersburg focusing on Lomonosov (Oranienbaum) as its case study. The study provides the analysis of the planning documentation developed for the city in the post-Soviet period. In particular, it elaborates on the currently enforced Strategy of Economic and Social Development of St. Petersburg-2030 (2014) and the City General Plan (2005), discussing the aspects of their development and implementation, as well as complex interrelation. Thereby, peculiarities of the spatial development of the St. Petersburg agglomeration are also investigated, elaborating on the state policy on agglomerations, historic development of St. Petersburg and relations with the Leningrad Region, governance and imbalances of the St. Petersburg spatial development, including proposed development scenarios. Consequently, the study employs a highly indicative case of the Lomonosov town municipal unit aiming to illustrate the practical implementation of administrative, territorial and strategic policies in a given context within a system of the state planning adopted in St. Petersburg, in particular, taking into consideration recently proclaimed necessity for the transition to a polycentric city model following an innovative scenario for the socioeconomic and spatial development. In particular, Lomonosov (Oranienbaum) is explored egarding its current socio-economic situation and development scenarios: industrial site and cultural tourism. The Oranienbaum museum and nature-reserve is also thoroughly assessed with regard to its cultural tourism potential. Finally, the urban environment of Lomonosov (Oranienbaum) is comprehensively scrutinized in terms of its historic development, residential housing typology, UNESCO World Heritage preservation and local urban heritage. In conclusion, the data on Lomonosov present in the St. Petersburg strategic and territorial planning documents is provided.},
  subject      = {Lomonossow},
  language  = {en}
}